MTPR Journal :: Modern Trends in Physics Research
	
	
	
	
	
	

	
	
	
	
	
	
	
	
	
	

	
	
	
	



	
	

Cairo University

MTPR Journal

 

Evolution of the binary neutron star system PSR1913+16 due to gravitational waves emission

2016-12-25 & doi: https://doi.org/10.19138/mtpr/(16)11-19
Shahinaz Yousef, Zeinab A. Mabrouk, Mostafa Kamal Ahmed

We have studied how the eccentric orbits of binary neutron stars evolve due to the emission of gravitational waves according to Popov and Imshennik method [1]. We have applied this method to PSR1913+16 binary system. Our results for this system are highly comparable with the latest analysis for that system based on published timing observations from 1974 through 2006 [2].The most important results from our study are: elliptical orbits shrink in size and become near circular at their late stages of evolution while the circular orbits don’t change their shapes; and most of the energy due to gravitational radiation emission is lost at high eccentricities near the periastron position.

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Angular Distribution and Transverse Momenta of Projectile Fragments of Oxygen Nucleus Collided with Emulsion at 3.7A GeV

& doi: https://doi.org/10.19138/mtpr/(19)58-61
A. Abdelsalam, M. S. El-Nagdy, A. M. Abdalla, A. Saber

Transverse-momentum and angular distributions of all residual charges due to fragmentations for 16O projectile on emulsion at 3.7A GeV are recorded and compared with that obtained for 12C, 22Ne, 24Mg and 28Si at the same momentum. The experimental parameters that indicate the mechanism responsible for projectile fragmentation are discussed. The effect of target size on fragmentation process for both 16O and 24Mg projectiles are studied. The results, in the given range of masses and energy show that there is unified mechanism responsible for projectile fragmentation.

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Two-dimensional system - black phosphorus: electronic, atomic structure and transport properties of bP(100) single crystals

& doi: https://doi.org/10.19138/mtpr/(19)50-57
Ionov A. M., Zagitova A. A., Bozhko S. I., Kulakov V. I., Zverev V. N.

The electronic, atomic structure and transport properties of black phosphorus (bP) single crystals prepared by high-pressure methods and a gas-transport reaction were studied by X-ray photoelectron spectroscopy (XPS) and scanning probe microscopy (STM, AFM). After exposure of the clean surface under atmospheric conditions, the features in the XPS spectra corresponding to the oxidized form of phosphorus were observed. The appearance of oxidized areas on the surface was also detected using AFM. The atomic resolution of the surface of a single crystal was obtained by the STM method. As a result of low-temperature transport measurements, impurity activation energies were determined, and negative magnetoresistance along the Y direction was detected.

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Thermodynamic properties of hot quark gluon plasma gas

& doi: https://doi.org/10.19138/mtpr/(19)45-49
M. H. M. Soleiman, S. S. Abdel-Aziz, A. Abdelfattah Omar

Identification of mass numbers concerning the nuclei ignite the atmospheric extensive air showers (EAS) is vital in the studies of Ultra High Energetic Cosmic Rays Interactions (UHECRI). The present study introduces a simple technique in processing of the shower data at the detector level (1400 m over sea-level) to identify the nucleus that starts the cascade of the EAS. CORSIKA 7.6900, which is the EAS-Monte Carlo generator is used to generate detailed data at detection level 1400 m over sea-level and energy ~ 10^6GeV. The data are analyzed and the energy spectrum is obtained for the generated EAS. The EAS spectra for light nuclei (H and He), medium nuclei (Mg), and Heavy nuclei (Ti, Cr, Fe) are obtained, totally and with photons are subtracted. It is found that, the spectral slope of the tail of the spectra with photons subtracted depend on the primary nuclei’s mass-number.

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Thermodynamic properties of hot quark gluon plasma gas

& doi: https://doi.org/10.19138/mtpr/(19)39-44
M. H. M. Soleiman, S. S. Abdel-Aziz, and A. I. Imsaeri

– In the present study a method is developed to get and explore thermal properties of hot infinite nuclear matter in the phase of quark gluon plasma-gas. Two models (modified from MIT model to fit experimental data in nuclei collisions) are used as case studies. The models were introduced in the form of parametric polytropic equations of state for quark gluon plasma gas. The volumetric specific heat capacity at constant volume c_v, the adiabatic speed of sound c_s, and isentropic compressibility κ_s of the quark gluon plasma (QGP) have been calculated as continuous functions of total energy density. It is found that the speed of sound increases as the energy content of QGP increases, while c_v and κ_s shows physical behavior like dilute gases.

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On the performance of a Flat Plate Collector

2019-09-15 & doi: https://doi.org/10.19138/mtpr/(19)31-38
M. K. El-Adawi, S. A. Shalaby, S. S. Mustafa, A. M. Abdul-Aziz

Flat plate collector with thin absorber is studied. Heat balance equation is solved to estimate the temperature of the absorber and its variation along the local day time. The same equation is used to determine the temperature of the working fluid. A published expression [20] to predict with good fitting the hourly global solar irradiance is considered as a source function for the incident solar energy. Three absorbers of different materials: Copper, Aluminum and Mica are considered. The water is considered as a working fluid. Two cooling conditions at the absorber front surface are considered. Factors affecting the efficiency are revealed.

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Powerful explosion of the ultraviolet light

& doi:
Kholmurad Khasanov

Schlieren Photography and Laser visualization helped us to detect in the atmosphere a field of constant ultraviolet explosions of light having power from hundred microwatt to one watt. Super-compression of ultraviolet in this field generates powerful explosions of light. The atmospheric ultraviolet explosions of light have the following characteristics: high frequency, wave super-compressibility and lacking power. The dynamic emitter of our design can transform lacking power atmospheric ultraviolet explosions into powerful explosions of the light from ten watt to thousand watt and more. The air, under the pressure of two-six bar comes in the dynamic emitter flows out and creates the supersonic jet. The interaction of the jet with low heat supply and the lacking power atmospheric ultraviolet explosions leads to focusing and super-compressing of the light wave, which calls powerful explosions of the ultraviolet light. These explosions carry out a nuclear decay, synthesize elements and porous nano materials. Recently, the Russian satellite Lomonosov, equipped with an ultraviolet telescope, recorded the powerful explosions of the light at an altitude of tens kilometers from the Earth. Russian scientists believe that explosions of the light in the atmosphere is a new physical phenomenon that modern science cannot explain yet. We assume that the powerful explosions of the light in the laboratory, the mechanism of which we present, as well as those fixed by the Russian satellite, are of the same physical nature.

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Production of Neutralino and Tow Higss Bosons from electron-positron annihilation via H0 and Z0 propagators

& doi:
M. M. Ahmed, Asmaa A. A., and Zainab A. H.

Production three neutralinos as the lightest supersymmetric particles (LSP) from the process in the framework of minimal Supersymmetric standard model (MSSM) and calculated the cross-sections for this interaction. We consider Produce χ ̃_i^0 (P_2 )+χ ̃_j^0 (P_4 )+χ ̃_l^0 (P_5 ) by one group of Feynman diagram through and propagators (from 1- 48 situations). (Where i ,j = 1, 2, 3, 4, and l=1). The cross sections are calculated according to a carefully selected set of Supersymmetric parameters, and the values of the cross sections ( ) pb are taken as a function of the incident center of mass energy ( ) Gev. Consider the neutralino to be the candidates for weakly interacting massive particle (WIMP) or cold dark matter (CDM). The values of cross-sections are taken at ( ) ranges from 300 to 1400 GeV. The all different possible situations are graphed and tabulated. The best cross section value ( ) is 2.5x10-10 pb when the neutralinos masses are at m_(χ ̃_i^0 (P_2 ) )=600Gev, m_(χ ̃_j^0 (P_4 ) )=600Gev, m_(χ ̃_l^0 (P_5 ) )=300Gev.

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Production three Neutralinos from electron-positron annihilation via H0 and Z0 propagators

& doi:
M. M. Ahmed

Production three neutralinos as the lightest supersymmetric particles (LSP) from the process in the framework of minimal Supersymmetric standard model (MSSM) and calculated the cross-sections for this interaction. We consider Produce χ ̃_i^0 (P_2 )+χ ̃_j^0 (P_4 )+χ ̃_l^0 (P_5 ) by one group of Feynman diagram through and propagators (from 1- 48 situations). (Where i ,j = 1, 2, 3, 4, and l=1). The cross sections are calculated according to a carefully selected set of Supersymmetric parameters, and the values of the cross sections ( ) pb are taken as a function of the incident center of mass energy ( ) Gev. Consider the neutralino to be the candidates for weakly interacting massive particle (WIMP) or cold dark matter (CDM). The values of cross-sections are taken at ( ) ranges from 300 to 1400 GeV. The all different possible situations are graphed and tabulated. The best cross section value ( ) is 2.5x10-10 pb when the neutralinos masses are at m_(χ ̃_i^0 (P_2 ) )=600Gev, m_(χ ̃_j^0 (P_4 ) )=600Gev, m_(χ ̃_l^0 (P_5 ) )=300Gev.

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Some Physical Properties of SBR/NBR Rubber Blends-Loaded with Nano-Sized Black Fillers

2019-09-01 & doi:
M. Hafez, A. S. Doma, A.Y. Zanaty, A. S. Abdel-Rahman, S.A. Khairy, H. H. Hassan

Different blends of SBR/NBR compatibilized by butadiene rubber (BR) were prepared according to the well-known standard methods. The modified blends of unfilled SBR/NBR was characterized on the basis of the effect of blend ratio by curing parameters, mechanical characteristics, abrasion resistance, compression set and swelling properties. It was found that SBR/NBR blends showed comparatively better mechanical properties compared to each rubber individually. Curing parameters e.g. low torque (ML) and high one (MH) were increased, while a reduction in the curing and scorch times were decreased with increasing SBR ratio in the blend. Results revealed that, the increase of SBR content results in an enhancement of tensile strength (TS) and elongation at break (Eb). The effect of blend ratio showed a peak value for (TS) & (Eb) at 50SBR/50NBR. For that, two types of carbon blacks, N220 and N774 were incorporated with the optimum blend ratio (50SBR/50NBR) by different concentrations. The effect of carbon blacks on the mechanical characteristics, hardness, abrasion resistance, compression test and even the swelling test in benzene have been discussed according to the recent current theories.

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Spectroscopic and thermal properties of PVK/AgNPs nanocomposites prepared by laser ablation

& doi:
F. H. Abd El-kader , N. A. Hakeem , I. S. Elashmawi , A. A. Menazea

Nanocomposites of Poly (n-vinylcarbazole) PVK/Ag nanoparticles were prepared by laser ablation of a silver plate in aqueous solution of chlorobenzene. The influences of laser parameters such as; time of irradiation, source power and wavelength (photon energy) on Spectroscopic, morphological and thermal properties have been investigated using Fourier Transform Infrared Analysis (FT-IR), Scanning Electron Microscopy (SEM) and Thermogravimetric Analysis (TGA), respectively. From IR data there is a complexation between AgNPs and PVK matrix. SEM reveals that the presence of AgNPs leads to changes in the surface morphology. Kinetic thermodynamic parameters such as activation energy, enthalpy, entropy and Gibb’s free energy are evaluated from TG data using Coat’s - Redfern model.

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Simulation of Fusion Evaporation of Compound Nuclei Created in Ultra Intense Laser Interaction with Carbon Targets

& doi:
*Loftia M. El Nadi1, *Magdy Omer, *Hussein Abdelmoniem , *Galila A. Mehena, *A.M. Aboulfotouh , *Khaled A. ElSayed,* A. I. Refaei, 1 Mohamed Ramadan, 2Mohamed Ezzat , 3Yasser ElBaz, 4Hisham Imam

Compound nucleus creation in Ultra Intense Laser UIL interaction with materials could be possible through Fusion-of the target nuclei with the accelerated target charged ion in the laser field. The residual radioactive nuclei in the remaining target material could well be due to evaporation of protons, neutrons, deuterons etc. from the created compound nucleus. We here with report simulation of compound nucleus formation followed by particle evaporation applying Monto Calro code PACE-4 to estimate the possible Fusion cross-section for carbon nuclei forming excited Mg24 compound nucleus. The results shown in Figure 1 indicates the highest cross section of such possibility peaking at carbon ions projectile energy ≈ 30 MeV (2.5 MeV/ A ). The cross sections for production of neutron deficient nuclei resulting from the Fusion-Evaporation process of C12 + C12 are also estimated. The simulation results help greatly in choosing the power of the UIL as well as the design of the experimental set up to be applied in verifying the Fusion-Evaporation Phenomena. FIGURE 1.1: Simple schematic of the four stages of inertial confinement fusion via “hot spot” ignition. Stage 1: Energy is delivered to the surface of a tiny hollow sphere (a few millimeters in diameter) of fusion fuel (the target). The blue arrows represent the driver energy delivered to the target-this is the laser light, x-ray radiation or particle beams that heat the outer yellow shell. Stage 2: Orange arrows indicate the ablation of the outer shell that pushes the inner shell towards the center. The compression of the fusion fuel to very high density increases the potential fusion reaction rate. Stage 3: The central low-density region, comprising a small percentage of the fuel, is heated to fusion temperatures. The light blue arrows represent the energy transported to the center to heat the hot spot. This initiates the fusion burn. Stage 4: An outwardly propagating fusion burn wave triggers the fusion of a significant fraction of the remaining fuel during the brief period before the pellet explodes/disassembles. Steady power production is achieved through rapid, repetitive fusion micro-explosions of this kind This image obtained from [1]

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Synthesis of Nano CdS by pulsed laser ablation in liquid environment (PLAL)

& doi:
Ayman M. Darwish, Wael H. Eisa, Ali A. Shabaka , Mohamed H. Talaat

A new method was developed to synthesize materials in nanoscale by using pulsed laser ablation in a liquid solution. Compared to the other synthetic methods, the advantages of this method are simplicity of the procedure and absence of chemical reagents in solution, which offers novel opportunities to solve the toxicity problems. This method can be carried by two ways; the first one is Top-Down technique appeared in publications in the last few decades while the other one is Bottom-Up technique appeared to be the first time in this paper. The both synthesized methods can be applied in all materials because of its ability to ablate almost all kinds of materials due to the ultra-high energy density and control over the growth process by manipulating the process parameters like Intensity, wavelength, etc.

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Preparation of silver nanoparticles to improve the physical properties for textile material

& doi:
Lotfia El Nadi, Ahmed M. Abdou, Mohamed A. Hafez, Mai Fayez Shahin

Silver nanoparticles have attracted much attention in antibacterial coatings, biological sensors, textiles, and biomedical devices because of their size-dependent properties. Pulsed laser ablation in liquids confine the movement of the resultant plasma plume which can greatly influence the kinetic properties. This causes distinctly different environments of the condensing phase formation from that of laser ablation of solids in vacuum or diluted gas. In this study, silver nanoparticles were prepared by two different techniques namely liquid phase pulsed laser ablation (LP-PLA) and chemical reduction. In the LP-PLA, IR and UV lasers types were used to ablate silver rods in distilled water. The IR laser was Nd:YAG with = 1064 nm, pulse duration = 6 ns, and 110 mJ laser energy. The UV type was nitrogen laser with = 337 nm, pulse duration = 15 ns, and 375 mJ laser energy. In the chemical reduction, silver sulphate, sodium borohydride, and tri-sodium citrate were used to prepare the silver nanoparticles. The fabricated nanoparticles were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and energy dispersive X-ray (EDX) microanalysis in order to analyze the final size and composition of nanoparticles. For sample prepared by Nd:YAG laser, the measured average size was found to be ~9.9 nm and sample prepared by chemical reduction showed average size of ~13.9 nm. The results show about spherical shape for samples prepared by Nd:YAG laser and chemical reduction while needle shape produced by the nitrogen laser. These silver nanoparticles will be applied to cotton fabrics for studying the dyeing behavior of the treated fabrics, such as color strength measurement and color fastness measurement.

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High Density Laser Induced Thermal Energy for Water Desalination

& doi:
*Loftia M. El Nadi1, *Magdy Omer, *Hussein Abdelmoniem , *Galila A. Mehena, *A.M. Aboulfotouh , *Khaled A. ElSayed,* A. I. Refaei, 1 Mohamed Ramadan, 2Mohamed Ezzat , 3Yasser ElBaz, 4Hisham Imam

Only 2.5% of all water in the world is fresh; even less than 0.1% is readily available for directhuman use. Water desalination proves to be a compelling necessity now and in the near future. Desalination techniques like multi-stage flash (MSF) or multi-effect distillation (MED) require heat for creating the steam which provides the fresh water. A handful of energy intensive techniques are currently used, mostly at industrial scale; however, Laser material heating energy can be used as an alternative to conventional sources of energy for water desalination purposes. Ultra intense laser sources are explored and a Terawatt laser system is found to be a potential candidate as a tremendous thermal energy source.

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ELI-ALPS Gas High Harmonic Generation Beamlines

& doi:
T. Mohamed, K. Varju, P. Dombi, Z. Diveki, S. Kuehn, P. Tzallas, G. Sansone, D. Charalambidis

Gas high-order harmonics generated (GHHG) by the nonlinear interaction of an intense ultrashort laser pulse with atoms or molecules are now used in many fields including atomic, molecular, plasma, and solid state physics. The interest in the generated radiation results from unique features like tunability over the extreme ultraviolet (XUV) and soft x-ray (SXR) spectral regions (reaching several keV), good beam quality, and ultrashort pulse duration down to the attosecond range. Currently many efforts are devoted to increase both the conversion efficiency of the GHHG process and thus the photon flux of the emitted XUV radiation. For this purpose ELI-ALPS are developing several GHHG beamlines. The main target of these beamlines is to provide the users of the ELI-ALPS facility with state-of-the-art attosecond pulses to perform pump-probe experiments with attosecond time synchronization between IR and XUV or XUV and XUV pulses. The under developement attosecond sources will operate at a repetition rate of 100 kHz and 1 kHz, using high-order harmonic generation in noble gases confined in either isolated attosecond pulses or short trains of attosecond pulses. The XUV radiation will be available in different spectral ranges (from 17 eV up to 90 eV) selected using different noble gases and metallic filters. The produced pulses and pulse-trains offered to the users will be properly characterized with respect to pulse duration, spectrum, photon number, spatial coherence and brightness. Further details about ELI-ALPS facility and the overview of the GHHG beamlines will be discussed at the conference.

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Study of refractive index for glass laser medium by using Clausius-Mossotti method

& doi:
Y.H.Elbashar , Y.S.Nada

The present work study the refractive index by using Clausius-Mossotti method, which deals with the ion refraction of the atoms for glass system with chemical composition as (x-42) B2O3. (100-x) Na2CO3.40ZnO.2Nd2O3 (where x=100, 95, 90, 85,80and75), density was measured, and the molar mass, refractive index, molar refraction, reflectance, phase velocity, Brewster angle, polarizability, electric susceptibility and elasto optic coefficient were estimated.

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Absorption Spectroscopy with Frequency Comb Lasers for Breath Analysis

& doi:
T. Mohamed, F. Zhu, J. Strohaber, A. A. Kolomenskii , Hans A Schuessler

Absorption laser spectroscopy ALS is a powerful technique for qualitative and quantitative studies of atoms and molecules in trace concentrations. As such ALS has applications not only in physics and chemistry but also in biology, environmental monitoring, and medicine. In the later field the analysis of the human breath is very useful for health monitoring and a rapidly expanding field for medical instrumentation, In this connection we developed an optical multi-pass cell based on highly reflecting confocal mirrors, achieving both long optical paths and dense atom space (volume) coverage to obtain high-sensitivity and high-selectivity . The system uses six mirrors, and we demonstrate a path-length of 300 m in a cell of only of 0.5 m in lenght. Different volume fillings and path lengths were achieved by tilting the mirrors with angles ≤ 0.05 radians. Spectrally resolved absorption measurements in the near IR of the greenhouse gases CO2, CO, and CH4 were carried out using a broadband frequency comb Er+ fiber laser beam including Raman shifting in a highly nonlinear fiber to an optical range spanning from 1.5 μm to 1.7 μm. Initially we recorded the absorption spectra of the first overtone rovibrational band for CO2, CO, and CH4 , and in the future we plan to quantify minute concentrations of additional biomarker gases and measure isotope ratios. In the case of methane a signal to noise ratio S/N=120 was obtained, yielding the estimated theoretical sensitivity of 6 ppmv, which can be further improved by optimizing the number of passes. Our optical apparatus is portable and can be used for a wide range of applications, including environmental monitoring, combustion processes, other medical diagnostics, and fundamental atomic and molecular physics studies. This work is supported by the Robert A. Welch Foundation grant No. A1546. The statements made herein are solely the responsibility of the authors.

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How to Optimally Collect Hyperentangled photons.

& doi:
S. F. Hegazy, J. El-Azab, Y. A. Badr, S. S. A. Obayya.

The creation of hyperentangled photons entails the two-photon emission over relatively wide extent in frequency and transverse space; generated photons are thus simultaneously entangled in energy, momentum and polarization. Because the creation process runs in nonlinear domain(s) which is always dispersive and birefringent, the output two-photon state undergoes loss of relative-phase coherence over frequency and space. This offers the vital role of spatial-spectral phase compensation so as to restore partially the state coherence in the two degrees of freedom. Behind compensation, the two-photon state emerges with much better phase flatness allowing collection over wider spatial and spectral ranges. However, as the spatial or spectral modes become further from the central compensated modes, stronger phase variations appears to dominate the scene. This excites two important experimental questions; what is the optimal combination of spatial and spectral filters a) that minimizes the overall phase variations at a given two-photon flux counts? b) that maximizes the two-photon counts at some accepted phase range? Here we address an experimentally convenient approach to determine the best answers of these two questions. The optimization process of the throughput-purity trade-off draws the main guidelines to design hyperentanglement sources whose intrinsic role in several protocols of quantum information and quantum computation.

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Liquid Crystal Photonic crystal Devices

& doi:
Salah Obbaya

Photonic crystal fibers (PCFs) have attracted the interest of many researchers in recent years due to their unusual optical properties. PCFs can be endlessly single mode over a wide wavelength range, and can be tailored to achieve nearly zero and flat dispersion over a wide range of wavelengths. Recently, some attention has been devoted to the possibility of infiltration of the air holes with different materials such as polymer, oil, or liquid crystal (LC). However, PCF structure infiltrated with a LC has unique and uncommon propagation and polarization properties. In this talk, novel designs of high birefringence LC PCF infiltrated with a nematic liquid crystal (NLC-PCF) are presented and analyzed. In addition, due to their different uses in communication systems, the performance of novel designs of high tunable polarization rotator, directional coupler, polarization splitter, and multiplexer-demultiplexer based on the NLC-PCF will be introduced. Moreover, LC Photonic crystal based optical router and image encryption will be presented. The simulation results are obtained using full vectorial finite difference method, and full vectorial finite difference beam propagation method, finite difference time domain method (FDTD) with nonuniform meshing capabilities and perfect matched layer boundary conditions.

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Aluminum tris-quinolate complex thin film producing novel blue laser

& doi:
Ragab R. Amin, Lotfia El-Nadi

High-quality Aluminum-tris-quinolate complex (Alq3) with oxasene Nile Blue (NB) layers were grown on glass substrates by thermal evaporation under vacuum. The photo-luminescence spectra show three distinctive peaks and their relative intensities change with mixture relative concentrations. The major emission peak at 4100 ± 20 Å has been identified. The I- V characteristics show a Schottky diode behavior for thin film double layers of NB-(Alq3-NB) mixture. Planer Blue Laser emission took place parallel to the substrate surface and perpendicular to the electric field direction starting at V = 0.28 ± 0.05 V. Threshold current of 0.088±0.012 mA and optical power densities up to 0.5 mW/cm2 were determined.

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Atmospheric Pressure cold plasma jet for Biomedical Applications

& doi:
Nasser N.Morgan, Mansour A.Elsabag, Ahmed AbdElRadi

ortant role in various applications such as material processing, and biomedical applications. Atmospheric Plasma jet (APJ) is one of the most widely used methods for generating non thermal atmospheric plasma. The jet plume consists of various groups of highly reactive chemical agents such as reactive oxygen species (ROS) including oxygen atoms O, hydroxyl group OH, hydrogen peroxide H2O2 and Ozone O3. The new field of plasma medicine is rapidly advancing toward the development of new medical therapies such as skin diseases, disinfection of dental cavities, dermatology, cancer treatment, and many others. The ROS generated by plasma jet can penetrate the cells and might induce high levels of DNA damage, resulting in apoptosis. The main goal of the paper is design and characterize atmospheric plasma jet APJ with high electron density and high reactive oxygen species (ROS) that targeting different types of cancer cell line (in-vitro) and other biomedical applications, through ROS-reaction mechanisms which can enhance the role of cold plasma cancer and medical therapy in Egypt. A schematic diagram and real photo of a dielectric barrier discharge plasma APJ is shown in figure 1a,b that is designed in our Lab.

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Liquid Phase Pulsed Laser Ablated TiO2 Nanoparticles Applied to Self-Cleaning Surfaces

& doi:
Lotfia El Nadi, Mounir F. Habib, Iftitan Azzooz

In this study, TiO2 nano-crystalline structures are fabricated using the LP-PLA technique. Nano-structural investigation was carried out by Electron Microscopy Measurements TEM, HRTEM, SEM , EDX and Electron Diffraction measurements. Optical properties were also determined by measuring absorption, emission and luminescence spectra of the Nano-crystalline TiO2. We then prepared a simple self-cleaning paint loaded with the TiO2 nanocrystals of different structural and/or optical properties. Coatings of the paint were made on aluminum, stainless steel and plastic surfaces representing materials applied in preserving food and medical systems. Self-cleaning of outdoor surfaces such as ceramics and cementious materials used in buildings were prepared by immediate loading with TiO2 nanoparticles and tested. In order to verify self-cleaning performances of photocatalytic cements/concretes, tests mainly based upon the degradation of methylen blue color and measuring the water contact angle for providing self-cleaning performances were carried out for materials. The experimental results introduce new information on visible light photocatalytic technologies of nano- TiO2 in providing self cleaning and antimicrobial surfaces often used in the open environment such as every day use of home utensils, buildings, and medical needed hygienic tools.

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Full wave solution and simulations of laser pulse amplification

& doi:
M. A. Khereldeen, M. Kotb, Osama M. Yassin

The need for low cost, compact, high- power laser systems with their applications in medicine and high energy physics is growing rapidly. Counter propagating laser pulses amplification promise a breakthrough by the use of much smaller amplifying media, that is, millimeter plasma scale. The full-wave solution for the two laser pulses interact in almost homogenous or plasma channel is conducted along with particle-in-cell simulation for the same pulses parameters. Motivated by the promise of reduced cost and complexity of the intense lasers, the amplitudes of laser pulses are taken to be small (a0 < 1). The growth rate of the seed pulse and the dephasing limitations are calculated. The results show that the energy is transferred from the pump pulse to the seed pulse effectively depending on the length of amplification and the isolation of the limiting conditions. A wide variety of system parameters such as frequency of laser pulses, plasma density matched to three waves interaction, and intensity of the pump wave and seed wave are studied. The influence of plasma and pulses parameters on simulation results are thoroughly investigated using a moving window technique and are compared with theoretical and numerical predictions. The comparison shows that the numerical full wave solution is very sensitive to any plasma density changes near the entrance of the pump pulse into the plasma.

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TRANSIENT TEMPERATURE DISTRIBUTION IN AUTOMATED PULSED PUMPING PASSIVELY Q-SWITCHED Yb:YAG SOLID-STATE LASER

& doi:
Jala M. El-Azab, Hamed M. Kandel

In this work, an enhanced technique for pulsed pumping was proposed denoted by Automated Pulsed Pumping (APP) technique. In this technique, a controlled system was suggested to detect the generation of the output pulse and control the pumping level. The technique is applied to a diode-pumped Yb:YAG laser passively Q-switched by Cr4+:YAG as saturable absorber by numerically solving the coupled rate equations describing the system. The thermal distribution, within the laser active medium of Q-switched solid-state lasers when subjected to APP, has been studied by solving the coupled laser rate equations simultaneously with the thermal conductivity equation. The thermal transient time and focal length in the cylindrical coordinates were also calculated.

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TRANSIENT TEMPERATURE DISTRIBUTION IN AUTOMATED PULSED PUMPING PASSIVELY Q-SWITCHED Yb:YAG SOLID-STATE LASER

& doi:
Jala M. El-Azab, Hamed M. Kandel

In this work, an enhanced technique for pulsed pumping was proposed denoted by Automated Pulsed Pumping (APP) technique. In this technique, a controlled system was suggested to detect the generation of the output pulse and control the pumping level. The technique is applied to a diode-pumped Yb:YAG laser passively Q-switched by Cr4+:YAG as saturable absorber by numerically solving the coupled rate equations describing the system. The thermal distribution, within the laser active medium of Q-switched solid-state lasers when subjected to APP, has been studied by solving the coupled laser rate equations simultaneously with the thermal conductivity equation. The thermal transient time and focal length in the cylindrical coordinates were also calculated.

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Methane Reforming Through spark discharge

& doi:
A. Abd Elradi, A. Samir, N. Morgan, M. Elsabagh, S. Hassaballa , F. F. Elaksha, A. A. Garamoon

Spark discharge has been used as a source of atmospheric non thermal plasma for methane reforming. Hollow electrode and gliding arc discharge have been used for the reforming process. Optimization and characterization of the two discharge systems have been investigated for maximum methane reforming. The two discharge systems work in two different range of methane flow rate, the first one is efficient for small flow rate (50-300 sccm), while the second one is efficient at high flow rate (100-5000 sccm). Maximum volume percentage of Hydrogen of about 83 % has been reached for the first system and maximum efficiency of the second system of about 75 gm/kWh has been reach for the second system .

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New Trends For waste water by Electro-spraying Corona Discharge

& doi:
Farouk Elakshar

New technologies are required always to find new methods for water treatments and solve waste water problems .Among the new techniques for waste water treatment there are: 1-the treatment of water by ozone (Garamoon et al., 2002), 2-AOP: advanced oxidation processes e.g. 1-photocatalysis on TiO2 surface (Feryal & Nur, 2003), 2-Fenton and photofenton process (Fares et al., 2008), 3-electrical discharge (Junwen et al., 2009),…..etc . Corona discharge is considered as one of the most efficient techniques in AOP processes (Sun et al., 1999). Generation of highly reactive oxidants, such as hydroxyl radical OH, atomic oxygen O, ozone O3 and hydrogen peroxide H2O2, has been obtained using corona discharge (Anpilov et al. 2001, Šunka et al., 1999, Malik et al., 2002 and Zhengguang et al., 2005). Unlike the methods which used under water corona discharge, the objective of the present work is to introduce a new design for waste water treatment using electro-spraying corona discharge system. The Advantage of Electro-spraying Corona Discharge system is that the surface area of the water is sprayed by the electro-spraying corona where the sprayed water passed through the entire regions of the corona discharge itself.

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Laser Induced Plasma Spectroscopy of Nano vs. Bulk Materials

& doi:
A. M. EL Sherbini

In this work, we present recent results on behavior of nanoparticles when irradiated with Nd: YAG laser pulses. The light emitted from plasma generated with a set of nanomaterial and bulk targets (ZnO, Fe3O4, Ag2O, TiO2, SiO2 and Al2O3) is compared for the same experimental conditions. The laser fluence was detuned in the range from 86 J/cm2 down to 2.5 J/cm2 with special emphasizes on the Ag2O nanomaterial. The targets are irradiated with nanosecond, pulsed Nd: YAG laser radiation, at 1064 nm in laboratory air. The spectra were recorded at the gate and time delay of 1 μs and for a constant spot size of 0.9 mm. The results show an exponential increase in the enhanced emissions with decrease of the laser fluence. The reversed behavior is discussed here. On the other hand, the laser fluence was kept at a constant level while the delay was changed in equal steps of 1 μs. The measurement of plasma parameters when utilizing optical emission spectroscopy technique reveals no significant variation of the relative electron density and temperature with laser fluence or delay time. The variation of the relative concentration with laser fluence, after correcting the measured spectral lines for self-absorption, attests that the enhanced emission can be attributed only to the relative concentrations. Possible explanations are based on changes in the physical properties of the nanomaterial upon subjected to high power laser pulses.

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Entanglement and Geometric Phase of Nonomechanical Resonators

& doi:
Mahmoud Abdel-Aty

We discuss different aspects of the relation between entanglemt and geometric phase of different systems. Information dynamics of charge qubits coupled to a nanomechanical resonator under influence of both a phonon bath in contact with the resonator and irreversible decay of the qubits is considered. The focus of our analysis is devoted to two qubits and the effects arising from the coupling to the reservoir. Even in the presence of the reservoirs, the inherent entanglement is found to be rather robust. Due to this fact, together with control of system parameters, the system may therefore be especially suited for quantum information processing.

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Transmyocardial Revascularization for Treating End Stage Coronary Artery Diseases

& doi: https://doi.org/Prof. of Solid State Physics, Physics Department, Faculty of Science, Cairo University hussamhhassan49@yahoo.com
Amr Zaher, Sherif Abdelhady, Yousry Moustafa, Yehia Badr

Coronary artery disease remains one of the leading causes of morbidity and mortality in developed countries. It is projected to be the leading cause of death in the developing world. Despite the success of current medical and surgical management of ischemic heart disease, a growing number of patients have diffuse obstructive coronary artery disease that is not amenable to coronary-artery bypass grafting or catheter-based interventions it is estimated that patients with ungraftable coronary artery disease account for approximately 5% of patients who undergo coronary angiography. This problem has stimulated interest in developing alternative therapeutic approaches. On a concept was based on the model of the reptilian heart, in which the left ventricle is directly perfused from endothelium-lined channels that radiate out from the left ventricular cavity. Mirhoseini and associates, advanced the concept by using laser energy to create the transmural channels. Subsequent clinical trials demonstrated that transmyocardial revascularization significantly improved angina in patients who were not candidates for conventional therapies such as bypass surgery, balloon angioplasty, or medical management.

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Study of the optical aspects of suitable new glass for Radiation Shielding Applications

& doi:
AlySaeed, Y.H.Elbashar, Y.S.Nada, S. U. El Kameesy

Lead oxide doped borosilicate glasses, in chemical composition 20SiO2-xPbO-(15+x)B2O3-5WO2-10ZnO-(50-2x)Na2O have been prepared using melt-quenching technique. The samples were examined by using Philips Analytical X-ray diffraction system in order to check the amorphous nature of the investigated glass samples. The effect of boron and lead oxides on glass transition temperature was carried out using Differential Thermal Analysis measurements (DTA). The results of DTA showed that both melting and glass transition temperatures decrease with the increase of lead and boron oxides. Density and its related parameters have been determined as a function of lead content. The optical properties of the glass samples have been obtained using UV-VIS measurements. The optical parameters, such as optical band gap, Urbach energy, refractive index, and electronic polarizability were estimated to study the effect of lead on the optical properties of prepped glasses.

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How Particle Accelerators Are Helping Us Treat Cancer?

& doi:
Fazal-e-Aleem, Lotfia El Nadi

Cancer is currently one of the major causes of death. So far we have limited success in treating this deadly disease. In the recent past, use of hadrons is growing becoming popular in treating cancer using conventional as well as laser driven accelerators. Our recent works encompasses that. In our current talk we will throw light on accelerators including LHC and their use through hadron therapy. We will particularly focus on the progress made so far.

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Factors affecting physical and physicochemical properties of NR/SBR rubber blends: I) Effect of blend ratio on the stress-strain characteristics for pure and carbon blacks filled composites

& doi:
H. H. Hassan1, S. S. Abdel-Aziz, A. S. Abdel-Rahman and M. H. Soleiman

Blends of Natural Rubber/Styrene Butadiene Rubber (NR/SBR) loaded with different ratios of N220:N774 carbon black fillers were prepared. The mechanical properties of pure blends and those loaded with different ratios of carbon black were investigated. The (50NR/50SBR), 40N220/(50NR/50SBR) and 60N774/(50NR/50SBR) blends were found to exhibit the highest values of tensile strength and elongation at break. The theoretical Mooney-Rivlin model applied to NR/SBR and supports the result of stress-strain. (50NR/50SBR) blends loaded with mixed ratios of N220 and N774 were also prepared. The stress-strain study of them did not show any significant change due to the order of addition of carbon black. The values of shore hardness (A) for all samples were measured and showed a marked increase by increasing the black content.

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The first-principles electronic structure calculations of chromia (Cr2O3)

& doi:
Abeer E. Aly

Chromia (Cr2O3) has been extensively explored for the purpose of developing widespread industrial applications, owing to the convergence of a variety of mechanical, physical and chemical properties in one single oxide material. It is one of the antiferromagnetic transition-metal oxides which present a challenge for electronic band theory. So we used the first principles calculations to study the magnetism of Cr2O3.The electronic structure calculations of chromia are studied by using full-potential linearized augmented plane wave (FP-LAPW) method implemented within Wien2k package. The strong electronic correlations between the d electrons on Cr atoms are taken into account using GGA+U method. Here, we present the calculations of density of state (DOS) and magnetic properties of chromia. Our calculations are in a good agreement with experimental values.

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Nano-Molar concentration of Cu(II), Zn(II) and Co(II) in Wastewater by a Novel Carbon paste ion-selective electrode

& doi:
Amal Khorshid, Ragab R. Amin, Yousry M. Issa

A novel highly selective sensitive for decreasing the detection limit for a Cu(II), Zn(II) and Co(II) have been fabricated fromion-selective electrode (ISE).The ISE is designed using acetaldehydethiosemicarbazone complex as ion-exchanger in carbon pastedissolved in tricresyl phosphate (TCP) as pasting liquid were prepared.This work describes the attempts to develop the electrodes, measurements of their characteristics and determination in real samples.The developed sensors exhibit good linear response of Nernstian slopes of 29.5±1, 28.5±1and 29.0±1 mV per decade over the concentration range of 5.0×10−8-2.0×10−3, 6.3×10−8- 7.9×10−3 and 3.3×10−8-8.0×10−3 M and a detection limit of 0.26, 0.5and 0.3nM for Cu(II), Zn(II) and Co(II) respectively. The sensors have a relatively fast response time of less than 10 s and the selectivity coefficients of the proposed electrodes revealed very good selectivity with respect to alkali, alkaline earth and some transition metal ions and could be used in pH range of 3.5-8.0. As a result the proposed electrodes were successfully applied to Cu(II), Zn(II) and Co(II) ions determination in mixture solutions and wastewater samples and as an indicator electrodes for potentiometric titration of ions with EDTA. The isolated complexes, HATS were synthesized by the anodic dissolution of metal in an anhydrous acetone solution of the ligands where HATS is acetaldehydethiosemicarbazone ligand and ac = acetone. Elemental analysis, magnetic susceptibility measurements, molar conductance, thermal analysis and spectroscopic techniques has been used for characterization and elucidation of the isolated complexes.

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EFFECT OF TEMPERATURE AND ADDITIVES ON THE ELECTRICAL PROPERTIES OF ZnO VARISTOR

& doi:
M.M.Saadeldin , M .Marawan and Mai Younis

Mixtures of ZnO and Ce6O11 as additive were prepared by solid state reaction from the calcined oxides with the following proportions 0.15, 0.25, 0.4 mol% . SEM revealed the presence of inter-granular phase. Phases developed were detected by XRD . XRD showed that no binary compound was formed. EDAX showed that cerium was detected in the ZnO grains confirming the XRD results. The conductivity is highly dependent on the microstructure of conducting grains surrounded by this insulating oxide barrier .The electrical conductivity was found to increase with the proportion of cerium oxide up to 0.25 mole then decreased.

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The influence of pH value on sol-gel preparation of PLZT polycrystalline powders

& doi:
M. Afifi, M.M. Rashad, A.M. Eid, L. Abd El-Latif, S.F. Mansour

The piezoelectric Lanthanum Lead zirconate titanate (PLZT) based ceramics with a composition of La0.6Pb0.94 (Zr0.52Ti0.48)O3 were studied using sol-gel auto-compulsion method. The specimens were fabricated and studied to understand the effect of ph7 adjustment on the microstructure, dielectric and the ultrasonic mechanical properties. The material was characterized for DSC/TGA and TEM studies. A polycrystalline single phase of PLZT with tetragonal structure was obtained, for the powder calcined at 600 for 3 h and 850 °C for 3 h. The electrical properties of the prepared ceramics were investigated as a function of the frequency using impedance analyzer. The remnant polarization (Pr) and coercive electric field (Ec) were calculated from the ferroelectric loop by Sawyer-Tower circuit.

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Synthesis and characterization of Tin oxide thin film, effect of annealing on multilayer film for sensing applications

& doi:
Mohamed Shaban, G. F. Attia, M. Basyoon , Hany Hamdy

Nanocrystalline Tin oxide thin films of multiple layers were successfully prepared by the sol-gel method. Spin coater have been used to deposit the films. The starting material is SnCl21. The SnO2 material was characterized by X-ray Diffraction (XRD), Scanning Electron Microscope (SEM) and EDS analysis. The optical properties (A, T, R) of the SnO2 thin film of various annealing temperatures (400,500,600 Co) and the electrical properties have been studied. Characterization results indicated that the products are composed of crystalline SnO2 nanoparticles which exhibit the cassiterite-type tetragonal crystal structure3. SEM revealed that with increase annealing temperature, the uniformity of the film increased. The variations of the refractive index (n), extinction coefficient (K) and Optical Conductivity with the wavelength have been studied. Nevertheless, the variation of the optical band gap with film thicknesses shows a significantly decrease in the values of the band gap with increase the film thicknesses. SnO2 was tested as a gas sensor to detect carbon dioxide (CO2) gas. It shows high sensitivity for various concentrations of CO2 gas2.

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Structural and physical properties of nanostructured barium doped BiFeO3

& doi:
M. A. Ahmed, M. M. El-Desoky, M. M. Mostafa, M.S. Ayoub

Nanometric multiferroic samples Bi1-xBaxFeO3; (BBFO, x = 0.10, 0.15, 0.20, 0.25) were prepared usingconventionalsolid-state method.The structural, particle size, dielectric and magnetic properties of the prepared samples were investigated. XRD patternsshow the formation of (BBFO) with single-phase rhombohedral-hexagonalstructure.At room temperature,antiferromagnetic BiFeO3 is converted to ferromagnetic on Ba doping. A change in the magnetization is observed around (742-833) K. Spin canting or impurity phase could be a probable reason for the origin of ferromagnetism. The dielectric properties of the nanoparticles were affected by the propertiesof the substitutional ions as well as the crystalline structure of the samples.

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Fabrication and characterization of silica @ silver core-shell nanoparticles using modified method

& doi:
M. A. Ahmed*, N. Okasha, and A. Allam

The nanocomposite particles of SiO2 @ Ag core shell were successfully prepared. Silica core has been synthesized by means of modified Stober process which was coated by silver to fabricate silica@ silver core- shell in 5 nm size. Silver nanoparticles were prepared by the reduction of Ag ions and PVP as a caping agent. Such core-shell nanoparticles opened new vision to be used in a wide range of applications such as: antibacterial, optics, electronics, catalystics, solar cells according to desired shape and size.

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Preparation and optical properties of PVA/Tio2

& doi:
A.M.Shehap*; Dana Saif Akil

The composite films of PVA/Tio2 were prepared successfully by using the solvent-casting technique with different composition ratios of the two materials (1.25, 2.5, 5 , 7.5 , 10 and 12.5 wt%Tio2). Ultrasonic were used in order to get better dispersion. Optical properties measurements explain the effect of adding Tio2 on absorption coefficient, refractive index, extinction coefficient and electronic transition. The absorbance spectrum was recorded in the wavelength range 200-1000nm.It was found that absorbance increase by increasing the amount of Tio2 in the film.

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The effect of dopant concentration on the thermal and opto-dielectric properties of GdCl3-doped polyvinylpyrrolidone nanocomposite system

& doi:
Mohammad A. F. Basha

Newly prepared and well-characterized nanocomposite thin films of polyvinylpyrrolidone (PVP), containing GdCl3 with percentages of 2, 5, 10, 15 and 20% by weight, are studied to investigate the effect of dopant concentration on the thermal properties, stability and degradation up to higher temperatures (500 oC) utilizing differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). A thermal transition of decomposition nature has been recorded for all samples in the range from room temperature to 150 oC. The heat consumed during this transition has showed a monotonic decrease with increasing dopant concentrations. Thermogravimetry has showed two degradation phases; at lower and higher temperature. Increasing the dopant concentration remarkably minimized the rates of degradation for the higher temperature phase. The effect of dopant concentration on the opto-dielectric properties was also investigated and the optical parameters, such as refractive index, extinction coefficient, real and imaginary parts of the dielectric constant and optical conductivity, were studied on the basis of optical data.

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Piezoresistive behavior of Multi Walled carbon nanotubes and Multiferroic nanoparticles / cement mortar composites

& doi:
M. A. Ahmed, S. I. El-dek and M. A. Shawkey

A new stain/stress sensor technology was developed, based on the concept of using Multi walled carbon nanotubes (MWCNTs) and Multiferroic nanoparticles. This new technology was manifested in concrete and mortar which greatly serve to decrease the crack depth. The use of sensors in civil structures is far from being common. In this work; there is no need to embed strain gauges or other sensors in the concrete, since the concrete itself is the sensor. The new sensor technology made use of new phenomena of the stress-induced electrical effect. This new phenomena is the change in nanomaterials/ composite contact electrical resistivity upon applying an external load on the cement composite. Concrete is somewhat electrically conducting; therefore it satisfies the basic requirement for the matrix of the composite material that senses using a new concept. The addition of conducting nanomaterials to concrete not only decreased the volume resistivity, but decreased also the contact resistivity between concrete and metal. A good electrical contact can be achieved simply by touching the concrete with the metal probe.

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Optimum Condition for Applied Ceria Nanoparticles as UV absorbance

& doi:
M. A. Ahmed, Samiha. T. Bishay* and Mai. M. El-Masry

Three different techniques have been considered to prepare ceria nanoparticels with and without Tween 80 as a surfactant.Phase formation and crystal structure were examined by X-ray diffraction (XRD) and high resolution transmission electron microscope (HRTEM). The particle sizes of the three prepared samples are 15nm, 5nm and 4nm. The measurements clarified the role of each of Tween 80 as a surfactant and the nanoparticle size on the values of zeta potential (ζ).The maximum zeta potential of un-surfactant nano-ceria in water medium was obtained at pH=5, accordingly, a neutral colloidal solution with small particle size without surfactant is suitable for medical applications. On the other hand, the results clarify that, UV absorbance depending on the refractive index of the dispersion medium and increases with decreasing the particle size for surfactant samples. These are interesting applicable results as a good coating, where the dispersed of small amount of nano-ceria in neutral water medium used to prevent UV hazards for essential fields such as furniture and medical bottles.

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Influence of B-site cation size variation of the physical properties of a canted AFM La0.7Sr0.3Fe1-xNixO3 multiferroic samples

& doi:
M. A. Ahmed*, N. Okasha, and A. Abd Elazim

Multiferroic La0.7Sr0.3Fe1-xNixO3; 0.0 ≤ x ≤ 0.2 nanometric samples were successfully synthesized using citrate-nitrate autocombustion method and their properties were systematically studied. All the samples were crystallized in a perovskite structure. The Goldschmidt tolerance factor for the perovskite decreased from 0.91 for La0.7Sr0.3FeO3 to 0.86 for La0.7Sr0.3Fe0.8Ni0.2O3 confirming that the crystal structure is orthorhombic. All the magnetic parameters such as effective magnetic moment (µeff), molar magnetic susceptibility (χM), and room temperature magnetization (MRT) decreased as Ni content increased, while the Néel temperature indicates the highest value (834 K) at x= 0.1.

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Enhancement of the Physical Properties of Ni-Zn-Cr Nanoferrite

& doi:
E. Ateia, L. M. Salah and A.A. H. El-Bassuony.

The effect of Cr3+ ion substitution on the structural, magnetic and electric properties of Ni0.7Zn0.3CryFe2-yO4, where 0.0≤y≤1.0 is studied. All the investigated samples prepared by co-precipitation method and calcined at different temperatures. X-ray diffraction analysis for all samples show that, the nanoferrite samples are pure single phase spinel structure up to y=0.3. Both of the crystallite size and lattice parameter decrease with increasing Cr content. Discussion has been made on the basis of a comparison of the effect of the average crystallite size and Cr3+ ion concentration on the electrical and magnetic properties of Ni Zn ferrite.

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Influence of (Glycine /Nitrate) Ratio on The Physical Properties of Gd3Fe5O12

& doi:
M. A. Ahmed, N.Okasha, S.I.El-dek, S.F. Mansour

Gadolinium iron garnet (Gd3Fe5O12-GdIG) was prepared using auto combustion method and glycine as fuel. The GdIG samples reveal single phase garnet with cubic symmetry. The effect of (glycine/ nitrate) ratio on the structural and magnetic properties of the investigated garnet is reported. The results of the study show that the lattice parameter decreases while a remarkable improvement of the densification is obtained with increasing (glycine/ nitrate) ratio

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Spin and Charge Density Maps of Nd2Fe14B

& doi:
Abeer E. Aly

The total charge density and the spin density are obtained by taking the sum or the difference of the spin-up and spin-down charge densities, respectively. We performed a pure spin polarized calculations on Nd2Fe14B using the self consistent Full Potential Linearized Augmented Plane Wave (FPLAPW).In this paper, we present the spin and charge density contours for rare-earth transition metal compounds e.g. Nd2Fe14B in the (001) and (110) planes using spin-polarized without spin-orbit coupling. The charge density map and the spin density map on the (001) and (110) plane of the tetragonal cell show the evidence for covalent bonding between Fe and B atoms.

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Tuning of energy gap with Al content in SmFe1-xAlxO3 multiferroic

& doi:
M.A. Ahmed, M.K. Abdelmaksoud, N.G. Imam, and Y. A. Saeid

Al doped SmFeO3 (SmFe1-xAlxO3; 0.0 ≤ x ≤0.15 with step 0.05) were synthesized by double sintering ceramic technique. XRD and FTIR were used to probe the structure of the nucleated perovskite. XRD and FTIR analysis confirmed the formation of single-phase orthorhombic crystals of perovskite structure. The optical properties of the sample were monitored by diffuse reflectance spectroscopy (DRS) and photoluminescence (PL) techniques. Diffuse reflectance spectra were used to study the surface properties of the samples. It shows three reflection bands at different regions. It was found that the band gap is tunable with Al content. PL spectra show UV, blue and red emissions slightly shifted with Al content. The PL intensity of multiferroic material enhanced with increasing Al content.

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Structural and magnetic properties of samarium bismuth strontium iron garnet Sm2.8-xBixSr0.2Fe5O12 (0.00 ≤ x ≤ 0.15)

& doi:
M. A. Ahmed,*, Samiha T. Bishay, Sh. A. Fareed

Garnet nanoparticles Sm2.8-xBixSr0.2Fe5O12 (0.0 ≤ x ≤ 0.15) were prepared by standard ceramic technique where the pre and final sintering were 950 and 1400 oC respectively for 10 hours with heating/cooling rates of 2 oC/min. X- ray diffraction (XRD) analyses were carried out to study the role of bismuth content on the phase formation as well as on the lattice parameter, density, porosity and crystallite size of these samples. The data revealed that the crystallite size decreased with increasing Bi-content from 102 nm at x = 0.0 to 28 nm at x = 0.15. Scanning electron microscope (SEM) showed that, the porosity of the samples was decreased with increasing Bi-content. The magnetization loop (M-H) was measured at room temperature using the vibrating sample magnetometer (VSM). The magnetic measurements clarified that the Curie temperature, the effective magnetic moment and the saturation magnetization increase with increasing Bi content. The obtained results were interpreted based on the garnet structure, the role of Bi as a thermal catalytic agent and the effect of particle size on the magnetic properties. This work recognized that, Bi substitution on samarium strontium iron garnet revealed to establish new nano material used for different technological fields.

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A New Theory on THE CREATION OF THE UNIVERSE

& doi:
D. A. E. Darwish

In the present research paper we have discussed the followings: (I). The previous theories published on the birth and the development (Evolution) of the universe, namely: (a) the Big Bang Theory, (b) the Oscillating Universe Theory, and (c) the Steady State Theory. (II). We presented our criticism directed to such theories concluded with a statement that NO BIG BANG HAD OCCURRED IN THE PAST OR IN THE FUTURE and that ALLAH is the God and there is no God but He, He is the Creator, the Maker, the Shaper and all that is in the heavens and the earth glorifies him. He is the Almighty, the ALL-Wise, the ALL-Knowing and the Most Merciful. The Universe is expanding as His will and He is the ALL-Powerful and such expansion is not due to anything like a big bang. (III). In this section are giving the first four items of the New Theory on the Creation of the Universe. i. ALLAH had ordained the measures of the creation of everything in the preserved Book before creating the Heavens and the Earth by fifty thousand years and His Throne upon water. ii. ALLAH prepared the Universe for Prophet Adam (Grandfather of the mankind) and his progeny. iii. ALLAH created everything. iv. ALLAH has honoured Adam and his progeny till the day of Resurrection. DARWISH: Publishing my NEW THEORY the World starts a new ASTRONOMICAL PERIOD.

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The Control of the Sun of North Atlantic Oscillation And Expectation of Rainfall Abundance Over Egypt

& doi:
Shahinaz Yousef, Mostafa El Rafey, H. M. Farid and Magda Moheb

The North Atlantic Oscillation (NAO) is a climatic phenomenon in the North Atlantic Ocean of fluctuations in the difference of atmospheric pressure at sea level between the Icelandic low and the Azores high. Through fluctuations in the strength of the Icelandic low and the Azores high, it controls the strength and direction of westerly winds and storm tracks across the North Atlantic. It is part of the Arctic oscillation, and varies over time with no particular periodicity. It is found that the sun controls the Sign of the NAO index. When the index is positive rain is abundant over North Europe and less rain falls over the Mediterranean. However, a negative index brings excessive rain to the Mediterranean. and drought over Northern Europe. According to our expectation the NAO switches to negative with weak solar cycles and this brings glad tidings to Egypt. Several deluges over Egypt are explained in this context.

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Ionization And Excitation Rate Coefficients For Ar XVI

& doi:
A. I. Refaie

Absolute ionization and excitation rate coefficients have been evaluated for arbitrary excited states at certain electron temperatures kTe and electron densities Ne of the Lithium-like ions Ar XVI. The populations of 24 excited levels are calculated for the doublet state of the Li-like Ar ion. The calculations have been carried out by using the coupled rate simultaneous equations in which the monopole and quadruple transitions have been introduced in the calculations in addition to the dipole transitions. A theoretical population model has been developed to study the influence of the different processes that might contribute to the population of the different levels at the plasma parameters. The population densities of these different levels were then derived from these rate coefficients.

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USE OF MULTILAYER TARGETS FOR ACHIVING HIGH PRESSURE OFF-HUGONIOT STATES USING INTENSE LASERS

& doi:
Hem Chandara Pant

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Dispersion of single-walled carbon nanotubes (SWCNTs) by using dimethylformamide (DMF) solution

& doi:
*Mongur Hossain1, M.M.H.Bhuiyan2

The dispersion of carbon nanotubes (CNTs) in liquid plays a crucial role in fundamental research and applied science. Ultrasonication is the most common technique to disperse CNTs. The surfactants used for CNT dispersion are ethanol, sodium dodecyl benzenesulfonate (SDBS), dodecyltrimethylammonium bromide (DATB), sodium dodecyl sulfate (SDS) and sodium dodecylbenzene sulfonate (NaDDBS). This research work presents the dispersion of SWCNTs by using a dimethylformamide (DMF) solution. The DMF is adsorbed on the surface of the nanotubes by a hydrophobic interaction. Ultrasonication helps DMF debundle the nanotubes by Coulombic or hydrophilic interaction, allowing the Van der Waals forces among the individual nanotubes to be overcome. UV-Vis spectra of dispersed CNTs in solution showed a maximum at 209 nm and decreased from UV to near IR. Field Emission Scanning Electron Microscope (FESEM) used to characterize the morphology of the SWCNTs thin films. And finally, the Fourier transform Spectroscopy was used to determine the interaction between surfactants and Carbon Nanotubes (CNTs).

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Nano-Eyes: 4D Atomic Force Microscopy (4DAFM) of the Effect of Suicidal Gene Nanoparticles on Live Cancer Cells.

& doi:
Hosam Gharib Abdelhady

The real time understanding of the suicidal gene effects on the cytoskeletal and nano-mechanical behaviors of cancer cells may provide new, effective ways in cancer gene therapy. Here, 4DAFM was applied to monitor the effect of targeted suicidal gen-nanoparticles on the morphological and nanomechanical properties of individual, dividing cancer cells in their environment. The mechanisms of forming the suicidal gene nanoparticles were also seen in 4D. Left; The transfection of single plasmid into a cancer cell, Right; the transfection of single plasmid-nanoparticles reaching the nucleous and kill the cancer cell.

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STUDY OF OUR STAR THE SUN

& doi: https://doi.org/10.19138/MTPR/(14)188-199
Sultana N. Nahar

Our sun is studied extensively as it is the standard for a typical star. However, knowledge about the Sun still has large discrepancies. Recent determination of abundances of common elements such as carbon, nitrogen, oxygen, etc. are up to 30-50\% lower than the current standard values. Much of these discrepancies could be reduced if a fundamental quantity, the opacity of solar plasma, is revised upwards. Propagating radiation in plasmas is absorbed and emitted by the constituent elements that constitute the opacity effect. Recently measured opacities at the Sandia National Laboratory on the Z-pinch nuclear fusion device, under stellar interior conditions created on the Earth for the first time, are 30-400\% higher than predictions for the most crucial element Iron. Theoretically, new large-scale calculations under the Iron Opacity Project reveal the existence of extensive and dominant resonant features in high energy photoionization. I will illustrate these and discuss how their inclusion should provide more accurate opacities, and close the gap between observed and predicted opacities and elemental abundances in the Sun. This work was supported partially by the U.S. National Science Foundation and the Department of Energy.

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Electronic growth of Pb nanoislands on Si(557) surfaces- STM studies and DFT modeling

& doi:
A.M. Ionov, S.I. Bozhko; A.S.Ksyonz

The Pb-islands growth on a clean vicinal Si(557) surface at room temperature has been studied using Scanning Tunneling Microscopy. We observed anisotropic tilted wedge-shaped Pb-islands to grow following the Stransky-Krastanov scenario. The elongation of the islands along the step edges of Si is associated with the anisotropic potential of the vicinal template. It was demonstrated that the growth of tilted Pb bulk islands is accompanied by their separation into layers which is clearly observed in the STM images as a slab-like stacking morphology, and also appearing from the statistical analysis. The single layer preferable thickness in the slab-like stacking like structure was found to be 2nm, which corresponds to 7 Pb monolayers. The results discussed in terms of electronic growth model. Using DFT simulations we argue that such growth mode is realized due to the minimization of the electron energy owing to the quantum confinement inside the created quantum wells. The growth mechanism can be explained in the framework of the electronic growth model including the interfacial strain and twin boundary formation. DFT simulation support that preferable position for Pb atom during growth of the 8th layer is hcp i.e. twinning boundary creation.

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Vicinal surfaces Si(hhm): templates for nanostructures fabrication

& doi:
S.I. Bozhko , A.N. Chaika, A.M. Ionov,

Atomically precise triple step staircase with a periodicity of about 6 nm can be fabricated on clean Si(557) surface using special sample treatment under ultra-high vacuum [1]. This semiconducting template is very promising for fabrication of low dimensional (1D, 2D) metallic and molecular structures with unique physical properties. However, despite numerous studies of metal/Si(557) systems, the precise atomic structure of clean Si(557) surface is still controversial [1-4]. The results of previous studies suggest that it can be related to the formation of different step arrays with different local surface orientations, i.e. Si(557) [1-3], Si(7 7 10) [4], Si(223) [5,6]. Here we report high resolution STM and LEED studies of well-ordered step array fabricated on a Si(557) sample with a miscut of 9.5° from the (111) plane using special annealing procedure with electric current directed perpendicular to the steps. The STM data show that after precise sample preparation the triple step array is extremely uniform: On some micrometer-scale surface areas the number of periodicity breakings can be as low as one per more than one hundred hill and valley sequences. According to our LEED and atomically resolved STM data the periodicity of this regular grating on the vicinal silicon surface is 5.9±0.2 nm that is most close to the Si(557) surface orientation. STM studies show that despite the high uniformity of the fabricated grating, there are at least four possible step and terrace configurations maintaining exactly the same groove periodicity throughout the surface. The atomic structure of the staircase and sample preparation strategy for fabrication of high quality step array and different nanostructures on the Si(557) surface are discussed.

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Ultrafast processes on semiconductor surfaces irradiated by temporally shaped fs laser pulses: Tuning & controlling micro/nanostructures

& doi:
P. A. Loukakos*, E. Stratakis, G. D. Tsibidis, C. Fotakis

The application of temporally shaped femtosecond laser pulses in the micro/nano-structuring of semiconductor surfaces is investigated. As an initial step towards full pulse shaping, sequences of double pulses with variable temporal spacing in the ps time domain with equal intensity have been used. Craters decorated with nm-sized ripples are formed following the laser-surface interaction depending on the irradiation conditions. The area, depth and strikingly the ripple periodicity show a dependence on the temporal delay between the individual components of the double pulses. Our analysis and explanation for the dependence of the micro and nano-morphological features on the pulse delay is based on our recently developed theoretical model that combines the laser-triggered ultrafast excitation and relaxation mechanisms on a semiconductor surface such as carrier excitation, ultrafast carrier-lattice energy exchanges and energy transport along with the slower phenomena of melting, the corresponding hydrodynamics and re-solidification that follow until the final surface morphology is established. The details of our model and our recent experimental investigations on laser-irradiated Si and ZnO surfaces will be discussed [1-4].

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Radiation of Directed Gravitation High-Energy Photon

& doi:
Kholmurad Khasanov

In electromagnetic field gravitation emits high-energy photon with direction reverse to direction of gravitation. This phenomenon was observed during gas electric discharge in [1]. Radiation of high energy gravitation photon was experimentally observed in numerous experiments [2]. The peculiarity of such phenomenon consists in the fact that while pumped by IR photon the range of the gravitation photons energies lies in UV range. The application of gravitation photon emission may be in energy source due to difference of photon energies mentioned above.

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Synthesis and Characterization of Graphene/zirconium oxide nanocomposite and its application in Photocatalysis

& doi:
Braj Raj Singh1*, Sneha Singh1, Mohd. Shoeb1, Wasi Khan1, H. B. Singh2 , Alim H. Naqvi1

In this study, we have synthesized Graphene/zirconium oxide nanocomposite (Gr@ZrO2-NC) by in-situ polymerization method. The structural, optical, thermal, electrical and photocatalytic properties of the as synthesized Gr@ZrO2-NC were studied. The XRD analysis ensures that zirconium nanoparticles (ZrO2-NPs) have a monoclinic structure. The characterization data confirmed that the ZrO2-NPs were successfully incorporated into the graphene sheets. TGA/DSC results exhibited an enhanced thermal stability of the ZrO2-NPs as compare with graphene owing to the strong interaction between the ZrO2-NPs and graphene. The energy band gap as calculated through the Tauc relation was found to be lower of synthesized Gr@ZrO2-NC. We have applied the synthesized Gr@ZrO2-NC for the efficient photocatalysis of a Rhodamine B (RhB) dye. The photocatalysis results exhibited the promising photo-degradation of the RhB dye under UV light irradiation through the production of reactive oxygen species (ROS). Thus, it is encouraging to conclude that Gr@ZrO2-NC has environmental significance.

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Diagnostics of Electron Temperature in Laser Produced Plasma From Iron Target Using Plasma X-ray Emission

& doi:
Mohamed Osman Awadalla and others

X-rays emitted from iron plasmas were used to calculate the temperature from the X-ray line intensity ratio. We used a Nd:YAG laser system, frequency doubled 532 nm, emitting 40 ps pulses at repetition rate 1 to 10 Hz. The energy on iron target was about 30 mJ corresponding to an intensity of 1013 Wcm2. X-ray spectra in the range 12 - 17 Å from iron targets were detected. According to Boltzmann law, a plot of the logarithmic term versus ΔE yields a straight line with slope equal to -1/T. The plasma electron temperature determined in this way was ~ 250 eV for Fe.

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TOTEM Measurements and Geometrical Picture

& doi:
Fazal-e-Aleem*, Haris Rashid, Sohail Afzal Tahir and Talib Hussain

TOTEM measurements give us clearer picture of diffractive scattering at TeVenergies. Together with measurements at GeV energies, theory faces a challenge. In our recent work, it was observed that by using Generalized Chou Yang model we can give a consistent picture of hadronic radii. In this talk, we will give an overview of current and future TOTEM measurements together with theoretical explanation.

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Innovative Applications of Nanotechnology in Preservation of Vegetables & Fruits, Agriculture and Biofuels

& doi:
Saiyed Alim Husain Naqvi

The power of science and technology is expressed through innovations which often results in rewards for society. The basic needs of society like food, health, clean water, cheap energy, transport, information and communication, good environment etc. are relevant even today. The society is still looking towards the technological advances to solve the age old problems related to its needs and alleviation form poverty. With the emergence of the nano-sclae technology i.e. Nanotechnology, hopes are high in every segment of social development for discovering novel solutions of the problems. The great physicist, R. P. Feynman who prophesied about the emergence of new technology had said with certainty that there will be enormous number of technical applications of this technology. The beauty of this discipline is that it is interdisciplinary, cuts across all industrial and technological sectors and is expected to lead next industrial and agricultural revolution. The soul of nanotechnology lies in the art of manipulation and control of matter at nano-scale, which has been employed by Nature for making things both living and nonliving since ages. Nanotechnology now leads an unending quest for knowledge and has provided a novel opportunity to climb a limitless ladder. This unconventional and interdisciplinary bottom up approach of manipulation of matter is sure to create wonders, provide simple solutions to difficult problems of human health and longevity, energy, water, agriculture, environment and may ultimately be successful in the creation of a prosperous and healthy society.

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Development of x-ray sources using PW laser systems at APRI GIST

& doi:
Hyung Taek Kim ; Kyoung Hwan Lee ; Hyeok Yun ; I Jong Kim ; Chul Min Kim ; Ki Hong Pae ; Jae Hee Sung ; Sung Ku Lee ; Tae Jun Yu ; Stéphane Sebban ; Fabien Tissandier ; Julien Gautier ; Adrien Depresseux ; Jaroslav Nejdl ; Michaela Kozlová ; Tae Moon Jeong ; Chang Hee Nam

A PW Ti:Sapphire laser with 30-J energy and 30-fs pulse duration has been developed at GIST and applied to generate x-rays and energetic charged particles. We present the status and plan of developing ultrashort x-ray sources and their applications. We successfully demonstrated x-ray lasers and their applications to high-resolution imaging. In addition, we plan to generate high flux x-ray/gamma-ray sources using the PW laser.© (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

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High Density Laser Induced Thermal Energy for Water Desalination

& doi:
*Loftia M. El Nadi1, *Magdy Omer, *Hussein Abdelmoniem , *Galila A. Mehena, *A.M. Aboulfotouh , *Khaled A. ElSayed,* A. I. Refaei, 1 Mohamed Ramadan, 2Mohamed Ezzat , 3Yasser ElBaz, 4Hisham Imam

We emphasize the importance of Creating facilities and programs for performing systematic studies at Cairo University relevant to Energy Production. Our goal is to utilize the thermal emery of inertial fusion induced by high density laser interaction with solid targets to desalinate sea water. We suggest catching up with what others already reached by establishing a pilot plant for studying the feasibility of turning the high density laser power to thermal energy. We plan to initiate unprecedented large experiments provided by high technological measuring equipments that are widely used in international laboratories, namely VULCAN in UK, HIPER in Europe, QBF in Korea, and NIF in LLNL in USA Such Laboratory for advanced HD Physics would be dedicated to the pursuit of Inertial Fusion Energy as a sustainable, clean and long term solution to mankind's energy needs whilst simultaneously provide a unique tool to do scientific and applied research that has direct impact on innovative industrial materials serving the Egyptian and the international Society. Other fields of applications are wide open to turn Cairo University to an International domain of advanced research. This would place Egypt on the Map of international research devoted to serve and upgrade society needs. It is worthwhile to mention that in Japan there are now more than 20 labs. In china 8, in Korea 4 in India 3, in Israel 2, in Russia several and in USA there are about 22 like laboratories. New Scientific young generation of researchers capable of handling and performing High Density Physics could easily be created through such project.

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Plasmonic Gold Nanoparticles meet laser light in the Cancer cell: following cell cycle, cell death, drug delivery dynamics and drug efficacy.

2014-12-20 & doi:
Mostafa Amr El-Sayed ‘s Group.

When metallic gold is reduced in size to the nanoscale, it becomes possible with weak resonant light to coherently excite large number of its conduction band electrons resulting in very intense electromagnetic fields. This intense field can decay by being either converted into heat that is used for the photo-­thermal therapy of cancer or converted into strong scattered light. The strong scattered light is used for imaging of cancer cells for diagnosis. If the enhanced scattered light from particles in cancer cells is spectrally analyzed, information about molecular changes occurring within the cell during its life functions or as it dies or drug treated can be revealed. By conjugating small concentrations of gold nanoparticles to the nucleus membrane of the cancer cells we were able to record its SERS (Raman vibrations) and/or its Rayleigh scattering images in the different phases of its full cycle1, or as it dies if given cancer drugs2, and enabled us to follow the dynamics of drug delivery3 and measure the relative efficacy of different cancer drugs4,5using either Rayleigh or SERS method of detection. Finally, SERS technique was used in developing a technique that enabled us to follow the time profile of the different processes involved in the death mechanism6 of a cancer cell caused by use of a cancer drug.

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Detection of interplanetary coronal mass ejections' signature using artificial neural networks

2016-12-31 & doi: https://doi.org/10.19138/MTPR/(16)1-10
Ramy Mawad, A. Radi, R. Saber, A. Mahrous, Mohamed Youssef, Walid Abdel-Sattar, Hussein M. Farid, Shahinaz Yousef

We have estimated the arrival time of interplanetary coronal mass ejection (ICME) shocks during solar cycle 23 (the period from 1996 to 2007) using the artificial neural network. Under our model, we could match 97% of the listed coronal mass ejection CME-ICME events selected by Cane and Richardson (2010) using the initial velocities of the ICME events. Whereas, when we used the ICME velocity at a distance 20R⊙, our model succeeded to match only 84% of the listed ICME events. The prediction of CME travel-time correlated to the initial speed of CMEs, we found a high correlation coefficient between initial speed of CME and calculated travel time under our model (R≈74) with power fitting. The prediction of ICME arrival time can be better estimated from initial speed and linear speed of CMEs more than from final speed or speed at 20 R⊙.

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On the correlation between Earth's orbital perturbations and oscillations of sea level and concentration of greenhouse gases

2015-06-01 & doi: https://doi.org/10.19138/mtpr/(15)1-9
Ramy Mawad

During the studied period 1996-2007 I noticed that, the rising and oscillations of the sea level, global temperature, carbon dioxide concentration, ice mass of Antarctica, and melting of Greenland ice are highly correlated with Earth's orbital perturbations. Monthly variations of those parameters have two periodicities. Stronger one called “long-periodic cycle”, it is strongly related to solar activity. It appears as a rising trend during my studied period. Observation data of iceberg mass and its melting, global sea level, and concentration of greenhouse gases such as carbon dioxide is recent and does not cover a millennium or Wolf-Gleissberg solar cycle. So, it does not indicate a global warming. Second cycle is called “short-periodic cycle”. it is a weaker force but still stronger than human activities forcing. It appears as oscillations around the rising trend. The short periodic cycle of all mentioned parameters is found correlated to Earth's orbital perturbations which are indicating a global warming and global warming is a natural phenomenon. Global warming is strongly corelated to Sun, Earth’s orbit, and our space. I conclude that the productivity of natural greenhouse gases is greater than that produced by human activity. The current proposed global warming is not a result of human activities, rather just temporary epoch and natural phenomena. The Earth's orbital perturbations are in an excellent positive coherence with the Greenland ice mass but in a negative coherence with the Antarctic ice mass. My results are in good agreement with Yousef (2000) and Akasofu (2010). I propose that the natural source of rising in concentration of greenhouse gases can be attributed to two causes: 1) Comets and asteroids, which are still carrying water molecules and some of greenhouse gas’ molecules to the Earth’s atmosphere; 2) Solar wind, which is composed greenhouse gases in ionization state. It may react and recombined though upper atmosphere before arriving to atmospheric lower levels at poles by unknown process. The global temperature is found to be correlated to Earth’s orbital perturbation too. This is because the declination angle is varying through the year. Output solar energy that arrives to the Earth depends on Sun-Earth distance too.

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Projectile fragmentation of 6,7Li nuclei in photoemulsion at Dubna energy

2014-12-19 & doi: https://doi.org/10.19138/MTPR/(14)175-187
M. Ismail, A. Y. Ellithi, M. M. Botros, Walaa M. T. Abd-Alaa

A semi-microscopic approach based on Skyrme energy density functional is used to study the effect of the depression parameter (β) of the density distribution of protons and neutrons on the total energy of nuclei with proton number Z = 18, 114, 116 and 120. For each element, two isotopes are considered. The variation of the contribution of the total energy parts with the depression parameter is studied. For super heavy nuclei, the variation of the lowest total energy curve with β has a shallow minimum, which occurs at negative value of β, suggesting that, these nuclei prefer large values of density at of their centers, these nuclei gain about 15 MeV in their binding energies within the β range considered. For the lightest Ar nucleus, the minimum is clear and occurs at positive value of β

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The energy dependence on the density depression parameter

2014-12-19 & doi: https://doi.org/10.19138/MTPR/(14)162-173
M. Ismail, A. Y. Ellithi, M. M. Botros, Walaa M. T. Abd-Alaa

In this work the fast target fragments from high multiplicity interactions of 16O (at 60A GeV and 200A GeV) and 32S (at 3.7A and 200A GeV) ions with Ag (Br) targets have been measured. The characteristics of these interactions have been compared to those from simulations using the Modified FRITIOF Code. The comparison indicates that there is a need to modify the code and incorporate a greater amount of rescattering for a better fit to the experimental data. The multiplicity distributions for all interactions have been fitted well with the Gaussian distribution function. The measurements of the scaled variance (ω >1) show that the production of target fragments at high energies cannot be considered as a statistically independent process. The energy dependence of entropy is examined. The entropy values normalized to average multiplicity (S /< Ng >) are found to be energy independent. The possibility of scaling, i.e., similarity in the multiplicity distributions of grey tracks produced in nucleus-nucleus interactions has been examined. A simplified universal function has been used to display the experimental data. The relationship between the entropy, the average multiplicity and the KNO function is examined as well.

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Missing energy within helium emitted in AA collisions at high energies

2014-12-19 & doi: https://doi.org/10.19138/MTPR/(14)155-161
M. S. El-Nagdy, A. Abdelsalam, B. M. Badawy

Using the multiplicity characteristics of the final state hadron, the shower particles emitted in the 4-pspace through 4He interactions with emulsion nuclei are studied in a few A GeV region. Basing on a universality of state, the multiplicity distributions, in the backward hemisphere of the space, are determined as a function of the target size. The shower particle multiplicity, while found to depend only on the target size in the backward hemisphere, depends on both the energy and system size in the forward hemisphere. It is seen that the shower particles are originated from two emission sources. One of both emits pion in the backward hemisphere, beyond the kinematic limits, as a target source particle regarding the limiting fragmentation hypothesis. The other is the main source which emits pion in the forward hemisphere as a result of a particle creation system. The results are analyzed in the framework of the Lund Monte-Carlo program code-events generating FRITIOF model.

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Results on the scaling of multiplicity distributions of fast target fragments in high energy nucleus-nucleus collisions

2014-12-19 & doi: https://doi.org/10.19138/MTPR/(14)148-154
A. Abdelsalam, S. Kamel, M. E. Hafiz, N. Sabry, N. Rashed

In this work the fast target fragments from high multiplicity interactions of 16O (at 60A GeV and 200A GeV) and 32S (at 3.7A and 200A GeV) ions with Ag (Br) targets have been measured. The characteristics of these interactions have been compared to those from simulations using the Modified FRITIOF Code. The comparison indicates that there is a need to modify the code and incorporate a greater amount of rescattering for a better fit to the experimental data. The multiplicity distributions for all interactions have been fitted well with the Gaussian distribution function. The measurements of the scaled variance (ω >1) show that the production of target fragments at high energies cannot be considered as a statistically independent process. The energy dependence of entropy is examined. The entropy values normalized to average multiplicity (S /< Ng >) are found to be energy independent. The possibility of scaling, i.e., similarity in the multiplicity distributions of grey tracks produced in nucleus-nucleus interactions has been examined. A simplified universal function has been used to display the experimental data. The relationship between the entropy, the average multiplicity and the KNO function is examined as well.

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Interactions in nuclear emulsion detector irradiated by a-particle

2014-12-19 & doi: https://doi.org/10.19138/MTPR/(14)137-147
A. Abdelsalam, Z. Abou-moussa, W. Osman, B. M. Badawy, H. A. Amer, M. M. El-Ashmawy, N. Abdallah

Using the multiplicity characteristics of the final state hadron, the shower particles emitted in the 4-pspace through 4He interactions with emulsion nuclei are studied in a few A GeV region. Basing on a universality of state, the multiplicity distributions, in the backward hemisphere of the space, are determined as a function of the target size. The shower particle multiplicity, while found to depend only on the target size in the backward hemisphere, depends on both the energy and system size in the forward hemisphere. It is seen that the shower particles are originated from two emission sources. One of both emits pion in the backward hemisphere, beyond the kinematic limits, as a target source particle regarding the limiting fragmentation hypothesis. The other is the main source which emits pion in the forward hemisphere as a result of a particle creation system. The results are analyzed in the framework of the Lund Monte-Carlo program code-events generating FRITIOF model.

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Empirical CME-SSC listing model

2014-12-19 & doi: https://doi.org/10.19138/MTPR/(14)130-136
Ramy Mawad, Hussein M. Farid, Mohamed Youssef, Shahinaz Yousef

The association listing of Coronal Mass Ejection-Storm Sudden Commencement (CME-SSC) events is the aim of this research. Certain criteria have been put to select the CME-SSC pair events automatically. The travel time of the CME shock could be estimated from an empirical equation that depends on spatial, temporal, CME angular width and projection effect conditions. A high correlation was found according to a certain algorithm between the initial speed and the travel time of the CME shock, R=0.81 with mean arrival time error 16.67 hours for 269 events during the period 1996-2010.

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On the solar stimuli that initiate Makkah Al-Mukaramah, Al-Madinah Al-Munawarah and Jeddah flash floods

2014-12-19 & doi: https://doi.org/10.19138/MTPR/(14)122-130
Shahinaz Yousef, Yasser h. O. Algafari, Ramy Mawad

Severe solar events manifested as highly energetic X-Ray events accompanied by coronal mass ejections (CMEs) and proton flares caused flash floods in Makkah Al-Mukaramah, Al-Madinah Al-Munawarah and Jeddah. In the case of the 20 January 2005 CME that initiated severe flash on the 22 of January. it is shown that the CME lowered the pressure in the polar region and extended the low-pressure regime to Saudi Arabia passing by the Mediterranean. Such passage accelerated evaporation and caused Cumulonimbus clouds to form and discharge flash floods over Makkah Al-Mukaramah. On the other hand, solar forcing due coronal holes have a different technique in initiating flash floods. The November 25, 2009 and the 13-15 January 2011 Jeddah flash floods are attributed to prompt events due to fast solar streams emanated from two coronal holes that arrived the Earth on 24 November 2009 and 13 January 2011. We present evidences that those streams penetrated the Earth's magnetosphere and hit the troposphere at the western part of the Red Sea, dissipated their energy at 925mb geopotential height and left two hot spots. It follows that the air in the hot spots expanded and developed spots of low-pressure air that spread over the Red Sea to its eastern coast. Accelerated evaporation due to reduced pressure caused quick formation of Cumulonimbus clouds that caused flash floods over Makkah Al-Mukaramah and Jeddah.

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A revolutionary theory on the origin of the Moon

2014-12-19 & doi: https://doi.org/10.19138/MTPR/(14)118-121
Shahinaz Yousef

So far, the theories of the origin of the moon are inadequate. There is no general agreement on any This paper brings to light a simple outstanding idea. The sun and the moon were once binary stars. Mass transfer occurred with the present sun gaining mass from the other star. Actually, the entire envelope of the other star was transferred to the present sun leaving the core of this companion. It is this core that cooled off and ended up as our moon. The face of the moon was cooled off abruptly while the back of the moon cooled gradually. This made the back of the moon almost free from Marias. We have to invoke another very important concept. The earth was created as an orphan planet. The binary suns system captured the earth as a circumbinary planet. Following mass transfer, the hot moon was captured by the earth and was locked in such a way that its near side always faced the earth. With both of the sun and the shinning hot moon, the earth experienced no night. The near side the moon was cooled off suddenly. This allowed night to occur on the earth. The far side of the moon cooled gradually and that made the observed discrepancy between the two faces of the moon. The very existence of He-3 on lunar surface, which is the product of fusion reactions inside the core of stars, is a clear-cut evidence that the moon is actually the core of a star. In addition, gamma ray photos of the moon show excessive illumination. This gamma ray is actually emanating from inside the moon as a byproduct of fusion reaction accompanying, He-3 production. An easy task to prove. In conclusion, When Armstrong stepped on the moon, he did not realize then that he actually walked on the cooled core of an ex star.

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Solar forcing on cyclones - case study: Gonu 2007

2014-12-19 & doi: https://doi.org/10.19138/MTPR/(14)111-117
Shahinaz Yousef, M. A. El-Rafy, Huma Abdallah Thani Al Hadabi

This paper establishes the physical cause and effect relationships between solar stimuli and terrestrial responses. The solar stimuli in our case is a fast stream of solar wind emanated from a coronal hole. This stream got through the Earth's magnetosphere like a bullet and hit a particular spot of the troposphere above the Arabian Sea on 31 May 2007. There the protons, ions and electron energies were deposited and heated the atmosphere. The hot spot expanded and formed a low-pressure spot above the Sea thus accelerated evaporation. The electric charges in this particular spot act as nuclei for water condensation and formation of intense clouds. As a second step, solar wind streams hit the two polar atmospheres, inducing two surface Meridional wind velocities that moved equator wards. The northern wind and the southern winds met at the cloud spot over the Arabian Sea and formed a torque that caused the clouds to rotate about the central eye. Thus, Hurricane Gonu was fully developed on early June 2007. Thus, the stimuli is the coronal hole stream and the response is the hurricane.

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Quantizated variability of Earth’s magnetopause distance

2014-12-19 & doi: https://doi.org/10.19138/MTPR/(14)105-110
Ramy Mawad, Mohamed Youssef, Shahinaz Yousef, Walid Abdel-Sattar

The size of the Magnetosphere is calculated during the period 1996-2011. It is discovered that the magnetopause distance D is quantized for D ≥ 8 RE. The magnetic levels are narrow towards the Earth but widely spaced outwards. This quantization disappears in the lower magnetosphere below 7 RE. Once the magnetopause is compressed to 8 -7 RE, multi doors get open which we call the Geomagnetic doors, and the solar wind is injected into the inner magnetosphere then to the ionosphere inducing SID and to the troposphere where it can cause flash floods and seeds of hurricanes

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Thermal stability and kinetic studies of gelatin/tgs composite films

2014-12-19 & doi: https://doi.org/10.19138/MTPR/(14)100-104
A. M. Shehap; Kh. H. Mahmouda; M. F. H. Abd El-kader Tarek M. El-Basheer

The composite films of gelatin and gelatin/TGS were prepared successfully by using the solvent-casting technique with different composition ratios of the two materials (2, 4, 6, 8 and 10 wt%TGS). Films exhibited similar X-ray diffraction (XRD) patterns, showing a displacement in position of the gelatin characteristic peaks. Thermal characterization was used to characterize the obtained films. Helix-coil transition and glass transition temperature were measured by differential scanning calorimetry (DSC). There is interaction between gelatin and TGS through hydrogen bond formation. Thermogravimetric analysis (TGA) was used to characterize the thermal stability of the composite films. The kinetic parameters such as activation energy, entropy, enthalpy and free energy for all the investigated samples were determined using Coats-Redfern and Horowitz-Metzger equations.

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Synthesis and characterization of Tin oxide thin film, effect of annealing on multilayer film

2014-12-19 & doi: https://doi.org/10.19138/MTPR/(14)90-99
Mohamed Shaban, G. F. Attia, Mohamed A. Basyooni, Hany Hamdy

Nano crystalline Tin oxide thin film of multiple layers was successfully prepared by the sol-gel method with, spin coater has been used to deposit the films. The starting material is SnCl2. The SnO2 material was characterized by X-ray Diffraction (XRD), Scanning Electron Microscope (SEM). The optical properties (A, T, R) of the SnO2 thin film of various annealing temperatures (400,500,600 Co) have been studied. Characterization results indicated that the products are composed of crystalline SnO2 nanoparticles which exhibit the cassiterite-type tetragonal crystal structure. SEM revealed that with increase annealing temperature, the uniformity of the film increased. XRD measurements showed that the grain size increased from 1.06, 1.48, 1.71 nm. The variations of the refractive index (n), extinction coefficient (K) and Optical Conductivity with the wavelength have been studied. Nevertheless, the variation of the optical band gap with film thicknesses shows a significantly decrease in the values of the band gap with increase the film thicknesses.

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Structural and multiferroic properties of nanostructured barium doped Bismuth Ferrite

2014-12-19 & doi: https://doi.org/10.19138/MTPR/(14)81-89
M. A. Ahmed, M. S. Ayoub, M. M. Mostafa, M. M. El-Desoky

Multiferroic nanoparticles of Bi1-xBaxFeO3 (x = 0.10, 0.15, 0.20 and 0.25 mol%) samples were prepared using conventional solid-state method. The nanostructural, multiferroic properties of the prepared samples were investigated. X-ray diffraction (XRD) patterns show the formation of BiBaFeO3 with single-phase rhombohedral-hexagonal structure. Spin canting or impurity phase could be a probable reason for the origin of ferromagnetism. At room temperature, remnant magnetization increased 18 times more than its initial value. A change in the magnetization is observed around 742-833 K. Néel temperature (TN) registers an increase of 30 times of Ba-doped BiFeO3 in comparison with undoped BiFeO3. The dielectric properties were affected by the properties of the substitutional ions as well as the crystalline structure of the present samples. Substitution with Ba2+ ions also improved the ferroelectric polarization with remanent magnetization polarization of 89 mC/cm2. The simultaneous occurrence of ferromagnetism and ferroelectric hysteresis loops in BiBaFeO3 multiferroic nanoparticles system at room temperature makes it a potential candidate for information storage and spintronics.

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Growth of layered wedge-shaped islands of Pb on the vicinal Si: new mechanism of twin boundary formation

2014-12-19 & doi: https://doi.org/10.19138/MTPR/(14)73-80
S. I. Bozhko, A. S. Ksyonz A. M. Ionov, D. A. Fokin, V. Dubost, F. Debontridder2, T. Cren and D. Roditchev

The growth of Pb on a clean vicinal Si(557) surface at room temperature was studied using the Scanning Tunneling Microscopy. We observed anisotropic tilted wedge-shaped Pb-islands to grow following the Stransky-Krastanov scenario. The elongation of the islands along the step edges of Si is associated with the anisotropic potential of the vicinal template. The observed peculiar slab-like stacking morphology of the formed wedge-shaped islands is discussed considering the substrate-induced strain, twin formation and the energy of the electron gas confined inside the islands.

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Effect of blending ratio and Carbon concentration on the stress-strain characteristics for NR/SBR Rubber

2014-12-19 & doi: https://doi.org/10.19138/MTPR/(14)65-72
A. S. Abdel-Rahman, M. H. Soleiman, H. H. Hassan, S. S. Abdel-Aziz

Blends of Natural Rubber/Styrene Butadiene Rubber (NR/SBR) loaded with different ratios of N220 carbon black filler were prepared. The mechanical properties of pure blends and those loaded with different ratios of carbon black were investigated. The (50NR/50SBR), 40N220/(50NR/50SBR) blends were found to exhibit the highest values of tensile strength and elongation at break. The theoretical Mooney-Rivlin model was applied to NR/SBR and supports the result of stress-strain characteristics. The values of shore hardness (A) for all samples were measured and showed a marked increase by increasing the black content.

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Vicinal Si(hhm) surfaces: templates for nanostructures fabrication

2014-12-19 & doi: https://doi.org/10.19138/MTPR/(14)58-64
S.I. Bozhko, A.N. Chaika, A.M. Ionov

Fabrication of well ordered low dimensional structures on clean and metal-decorated stepped Si(hhm) surfaces is discussed. The atomic structure of clean Si(557)7×7 and Si(556)7×7 surfaces fabricated using special annealing procedures and metal-decorated Ag/Si(557) and Gd/Si(557) systems has been studied using high resolution scanning tunneling microscopy and low energy electron diffraction. The investigations demonstrate feasibility of fabrication of 1D- and 2D-structures of gadolinium and silver atoms on the Si(557) surface.

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The electronic band structure of Nd2Fe14B from First-Principles calculations

2014-12-19 & doi: https://doi.org/10.19138/MTPR/(14)52-57
Abeer E. Aly

Electronic structure calculations for the permanent magnet material Nd2Fe14B has been calculated using spin-polarized full potential linearized augmented plane wave (FPLAPW) method. This method is highly effective for systems with very complex structures. The results presented include the band structure of Nd(4f) site and their partial density of states (DOS). The band structure for Nd (4f) site is in good agreement with the self-consistent calculations. We calculated the results for Nd2Fe14B by spin polarized without spin-orbit coupling.

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Blends of Natural Rubber/Styrene Butadiene Rubber (NR/SBR) loaded with different ratios of N220 carbon black filler were prepared. The mechanical properties of pure blends and those loaded with different ratios of carbon black were investigated.

2014-12-19 & doi: https://doi.org/10.19138/MTPR/(14)42-54
P. A. LOUKAKOS , E. STRATAKIS, G. D. TSIBIDIS, D. GRAY, M. BARBEROGLOU, C. FOTAKIS

The application of temporally shaped femtosecond laser pulses in the micro/nano-structuring of semiconductor surfaces is demonstrated. As an initial step towards full pulse shaping, sequences of double pulses with variable temporal spacing in the picosecond time domain with equal intensity have been used. Craters decorated with nm-sized ripples are formed following the laser-surface interaction depending on the irradiation conditions. The area, depth and strikingly the ripple periodicity show a dependence on the temporal delay between the double pulses. Our analysis and explanation for the dependence of the micro and nano-morphological features on the pulse delay is based on a combination of mechanisms including laser-triggered ultrafast excitation and relaxation on a semiconductor surface such as carrier excitation, ultrafast carrier-lattice energy exchanges and energy transport along with the slower phenomena of melting, the corresponding hydrodynamics and re-solidification that follow until the final surface morphology is established. Our investigations on laser-irradiated Si and ZnO surfaces are discussed.

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Directed Radiation of High-Energy Light Against Gravity Vector

2014-12-19 & doi: https://doi.org/10.19138/MTPR/(14)33-41
Kholmurad Khasanov

In this article are described the gravitation-light interaction and its characteristics. The frequency of light emitted from the source depends on its position in space. This phenomenon was detected in experiments with gas electric discharges, incandescent wires and lamps. The change in frequency is observed along the gravity vector. Experiments provide evidence of potential gravitational energy turn into the energy of electromagnetic radiation.

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Full wave solution and simulations of laser pulse amplification

2014-12-19 & doi: https://doi.org/10.19138/MTPR/(14)26-32
M. A. Khereldeen, M. Kotb, Osama M. Yassin

The need for low cost, compact, high- power laser systems with their applications in medicine and high energy physics is growing rapidly. Counter propagating laser pulses amplification promise a breakthrough by the use of much smaller amplifying media, that is, millimeter plasma scale. The full-wave solution for the two laser pulses interact in almost homogenous or plasma channel is conducted along with particle-in-cell simulation for the same pulses’ parameters. Motivated by the promise of reduced cost and complexity of the intense lasers, the amplitudes of laser pulses are taken to be small (a0 < 1). The growth rate of the seed pulse and the dephasing limitations are calculated. The results show that the energy is transferred from the pump pulse to the seed pulse effectively depending on the length of amplification and the isolation of the limiting conditions. A wide variety of system parameters such as frequency of laser pulses, plasma density matched to three waves interaction, and intensity of the pump wave and seed wave are studied. The influence of plasma and pulses parameters on simulation results are thoroughly investigated using a moving window technique and are compared with theoretical and numerical predictions. The comparison shows that the numerical full wave solution is very sensitive to any plasma density changes near the entrance of the pump pulse into the plasma.

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Fine structure calculations of atomic data for Ar XVI

2014-12-19 & doi: https://doi.org/10.19138/mtpr/(14)16-25
A. I. Refaie

Absolute ionization and excitation rate coefficients have been evaluated for Lithium-like Argon ion in the plasma for some arbitrary excited states at certain chosen electron temperatures kTe and for electron densities Ne. The populations of 24 excited levels are calculated for the doublet state of the Li-like Argon ion. The calculations have been carried out using the coupled rate simultaneous equations including the monopole and quadruple transitions in the calculations in addition to the dipole transitions. A theoretical population model has been developed to study the influence of the different processes, contributing to the population of the different levels on the plasma parameters. The population densities of these different levels have then been derived using these rate coefficients. Neither experimental nor theoretical data have been found in literature for comparison.

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Fine structure calculations of atomic data for Ar XVI

2014-12-19 & doi: https://doi.org/10.19138/mtpr/(14)1-15
A. I. Refaie

Fine structure energy levels, wavelengths, log gf and allowed transition probabilities (E1) have been calculated for Lithium-like Ar XVI. The optimized electrostatic parameters by a least square approach, have been used in the calculation to include the configuration interaction and relativistic effects. A total number of 69 Ar XVI levels having total angular momenta, 1/2≤ J ≤9/2 of even and odd parities, orbital angular momenta 2≤ Ɩ ≤ 4, with 546 E1 transitions for 6≤n≤10 are considered using the relativistic effect in the Breit-Pauli method, where n is the principal quantum number. A comparison is made with the available results in literature.

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