Table of contents

Preface

Research Activities in Particles, Materials and Energy are considered nowadays as the pillars on which recent and future developments of human civilization are founded. Fruitful results of these activities should drastically improve the quality of human life and help in protecting the environmental balance on earth. The main objective of the present conference is to discuss very recent original investigations carried out in the areas of particle and astrophysics with possible existence of antiuniverse and antigravity, nanomaterials synthesizing and characterization, nuclear energy, sustainable energy and radiation protection. Special attention is devoted to medical and industrial applications of Laser and treatment of defects in solids via positron annihilation techniques.

The scientific activities of the conference were displayed as Keynote Lecture given by a Leading International Invited Scholar, Plenary Talks presented by Invited Speakers, Regular Talks presented by distinguished participants and oral presentations of few selected Abstracts. The Poster Session is devoted to all other accepted Abstracts.

The sessions of the Conference covered the following topics:

TOPIC 1: Medical and Industrial Applications of Laser

TOPIC 2: Particle and Astrophysics

TOPIC 3: Positron and Positronium Physics

TOPIC 4: Materials Characterizations

TOPIC 5: Nanomaterials and Nano Technology

TOPIC 6: Nuclear Plants and Sustainable Energy

TOPIC 7: Radiation Physics

List of Editor in Chief, I- Honorary Editorial Board, II- Members of the Editorial Board, Acknowledged Editorial Board are available in this PDF.

List of Photographs are available in this PDF.

All papers published in this volume of Journal of Physics: Conference Series have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

This work discusses laboratory experiments using atomic and molecular spectroscopy for diagnosis of laser-induced phenomena of interest in the field of medicine, and in astronomy for the understanding of recorded spectra from selected stars. Photo-acoustic spectroscopy utilizes femtosecond laser-pulse trains for diagnostic and therapeutic applications. Optical emission spectroscopy explores nominal nanosecond laser-induced, nano-particle plasma and its detection sensitivity. The study of laboratory plasma generated in selected gas-mixtures reveals insights for the interpretation of white dwarf spectra.

This work discusses nano-particle augmentation of signals in laser-induced plasma spectroscopy. Radiation from a Nd: YAG laser device generates optical breakdown at nano-structured target materials. Extensive scientific investigations of different types of nanomaterial explore dependencies on nanoparticle size, laser wavelength and fluence, and time delay to obtain stronger signals from nano-material than from corresponding solid bulk matter. Modelling of the measurements interprets the occurrence of enhanced detectability of atomic species. Opportunities present themselves for biological and spectrochemical synthesis.

Gold nanoparticles have unique physical/chemical properties which let them very useful in several applications. In addition, to their biocompatibility which is very important for biomedical applications. Recently gold nanoparticles and reactive species of cold plasma have been successfully used for tumor cells and cancer treatment. This method depends on the type of reactive ionized species or the size of gold nanoparticles which it produces and its directed effect on the cell cycle. Our proposed novel designed system which combines both gold nanoparticles and reactive species of nitrogen and argon cold plasma is obtained. Therefore, generating singlet oxygen and reactive species with confirming gold nanoparticles stability as well as to its exposure to cold plasma at different conditions and time periods is accomplished. The analysis of this system will be done using Raman spectroscopy technique. This procedure will enhance better, direct, effective and selective targeting for different kinds of bio-threats such as tumor cells, bacteria, fungi, and virus. This innovative system may be used as a new sterilized technique for different fields such as medical and biological sector, and more promise as cancer therapy selective technique.

Thermal effects induced in a finite silver selenide slab by CW laser source are studied. The hyperbolic heat conduction equation (HHCE) in dimensionless form is solved using Laplace integral transform technique. Different laser power densities are considered. Expression for the temperature field within the target is obtained. As an illustrative example, the critical time required to initiate phase transition and that required to initiate melting are computed for different pulses.

The main purpose of this research is to evaluate irradiance levels delivered by non-conventional phototherapy devices.This evaluation can help to save energy, achieve better treatment and improves available intensive phototherapy quality in use in several hospitals in Egypt. The irradiated energy and uniformity of non-conventional phototherapy devices (n=36) were evaluated at nine hospitals in Egypt. These devices were categorized as three groups including; bilibeds with LEDs, bilibed with fluorescent lamps and bilisphere. The irradiance levels were measured using a phototherapy radiometer. The results show that the irradiance levels ranged from 20.3 to 93.1μW.cm^-2.nm^-1 and the LEDs bilibed devices produce average irradiance levels approximately double of those results from bilisphere with fluorescent lamps. Otherwise, the bilibed with fluorescent lamps (present about 30 % of the non-conventional phototherapy devices studied) is not adequate for intensive phototherapy. Any assessment of the irradiance energy of the phototherapy devices using a suitable calibrated sensor (radiometer) is mandatory in developing countries. The phototherapy devices that produces an adequate and accurate irradiance levels would increase the degradation rate of bilirubin in the blood and hence minimize the necessity to blood transfusion substitution. LEDs bilibeds produce sufficient electromagnetic energy for jaundice treatment. It can be used alone for intensive treatment better than the bilibed with fluorescent lamps and the bilisphere.

The main objective of the present paper is to discuss the consequences of matter-antimatter interaction at low energy. The production of large number of cooled antimatter in laboratory and the formation of exotic atoms composed of particles and antiparticles are reviewed. Particularly, the quantum mechanical treatment of Four-Body exotic molecules is shortly discussed. The main goal of the paper is to shed light on possible novel discoveries and applications based on the coexistence of matter and antimatter.

Although non-baryonic dark matter seems essential in the context of the currently favoured cosmological model, the standard dark matter scenario is facing problems: experimental searches have failed to find the relevant particles, closing the mass-corssection window of the 'WIMP miracle', and the model suffers from problems on (sub) galactic scales. The cold dark matter (CDM) invoked may turn out to be too cold and needs to be heated; so that its solution to the dearth of visible matter in the outer parts of galaxies is not accompanied by the problem of an excess of matter in their centres (along with other possibly related problems, such as the numerical excess of predicted satellites). After a heuristic introduction to some aspects of the rationales that lead to the CDM paradigm, I discuss the properties of self gravitating CDM structures (haloes) and the proposed reasons for their apparently 'universal profiles' (including new simulations attempting to explain aspects of their advent), the galactic-scale problems associated with them, and proposed solutions, focussing on baryonic solutions and the recently topical ultra-light axion particles as replacement for the standard weakly interacting massive particles (WIMPs). It is hoped that at least parts of this review would be helpful to a general physics audience interested in the problem of dark matter in an astrophysical context.

In this study, the concept of magnetically charged black hole is discussed through calculating the angular momentum (L) of its interaction with an electric test charge. Results confirm that the angular momentum form will agree with the prediction of no-hair theorem and we will show that L will depend on the distance between the charge and the black hole.

We consider one dimensional Ising spin system in a transverse uniform time-dependent magnetic field. The asymptotic behavior of the bipartite entanglements between the terminal spin and each one of the other spins along the chain is investigated and compared at different spin-spin interaction ranges, from nearest neighbor to infinite long range, under the separate action of two different magnetic fields, constant and time-varying. We find that each of the nearest neighbor and next to nearest neighbor bipartite entanglements reach an asymptotic final state that is independent of the initial condition or the variation in the interaction range showing perfect ergodic behavior at quite short interaction ranges. However, the nearest neighbor entanglement maintains this behavior at a slightly longer ranges. The other bipartite entanglements assume a zero value within these interaction ranges. At intermediate short and long interaction ranges, the asymptotic states of all entanglements become strongly dependent on the initial state and the interaction range, deviating from the ergodic behavior observed before. The maximum asymptotic entanglement attainable between a pair of spins takes place at a long interaction range value that increases with the distance between the spins. At the infinite long range interaction, the dynamics of all bipartite entanglements coincide. great care should be taken in constructing both.

Capacitively coupled RF discharges (RF-CCPs) can offer a higher quality of semiconductor fabricating and processing thin film by applied full y arbitrary waveforms. Using different applied arbitrary voltage waveform, one can design varies distributions with specific tailoring features. Analyzing RF -CCPs dynamics using non-harmonically modulated sheath is more complicated. In this theoretical study of fluid model, various types of excitation waveforms, such as square, sawtooth, dual frequency, and pulse-like excitation were applied. Furthermore, different important semi-analytical descriptions, such as the particle density, instantaneous electric field distributions, the voltage and the effective charge-voltage of time characteristics of arbitrary waveforms are obtained. By applying the collision and collisionless self-consistent numerical solutions of the fluid model all complex dynamics are accomplished. In addition, by using the model of an ensemble in space-time (EST) it is found that arbitrary waveforms can offer more possibilities for tailoring IEDs for a purpose in collisionless regimes more than collisional regimes. Moreover, mo re control of RF-CCPs will be achieved for the different purpose of materials processing.

The prediction of the global solar radiation through a distribution function q(t), W/m2 for clear days is given where "t" is the local day time.: The distribution is based on a simple model and is expressed through well-established parameters such as the length of the solar day "t_d" and the maximum value of the received solar irradiance q_max, w/m² at time instant "t_o".q_max is expressed in terms of the solar constant. Comparison between the computed values of q(t) and the corresponding published experimental data for Hong Kong (China), Valencia( Spain) and Makah (Saudi Arabia) are given as illustrative examples. A test for the degree of fitting is also clarified.

The exact equations of the thermoluminescence (TL) glow curve deconvolution that describe the intensity of a single TL glow peak of different order kinetics, which are obtained from the one trap-one recombination (OTOR) level model, are considered. The reformulation of the expressions of the intensities of TL glow peaks in terms of the peak intensity I_M, peak position T_M, and the activation energy ∈, for each order of kinetics are achieved. The authors developed a MATLAB computer code, which utilizes the obtained equations, to computationally deconvolute the TL glow curves. The code is used to investigate the reference glow curves of the GLOCANIN program. The obtained results agree with those previously reported by the GLOCANIN project with better values of the figure of merits FOM. The considerations of the obtained equations show promising trends to understand a peak formation for different order kinetics that belong to the OTOR level model.

Abstract The Tsallis entropy for a system that interrelates with the Hellmann potential is calculated and discussed. The calculation is done in the position and momentum spaces using the J-matrix method. Most of our outcomes are reported for the first time. The results are compared with the available literature results.

The extraction of material positron lifetime components from positron annihilation lifetime spectroscopy measurements, performed using conventional unmoderated radionuclide positron sources, requires accurate knowledge of both the spectrometer instrument timing resolution function (IRF) and annihilation events extrinsic to the material, the source correction terms. Here we report the results from study of spectrometer performance made using two reference samples, high purity polycrystalline aluminium, and stainless steel supplied by the National Metrology Institute of Japan (NMIJ RM 5607-a). Both prepared with directly deposited ²²NaCl positron sources. The IRFs obtained by fitting spectra from both reference samples were monitored with time to evaluate spectrometer stability and to compare methods of IRF determination. Using the aluminium IRFs the analysis of spectra from the NMIJ stainless steel reference samples yielded a single lifetime component with value 106.9(9) ps.

Simple and low-cost hot-injection method was used to synthesize three samples of colloidal nanocrystals with general chemical formula CuIn_1-xGa_xSe₂ (x=0.0, 0.6 and 0.82). X-ray diffraction (XRD) and transmittance electron microscopy (TEM) have been used to investigate the structural properties of the synthesized nanocrystals and proved their high crystallinity. Positron annihilation lifetime (PAL) and Doppler broadening (DB) techniques were used to give more insights on the structural defects of the grown samples. The results of the positron lifetime measurements indicate that the shortest lifetime component (τ₁) with intensity ≳ 97% is greater than the calculated positron bulk lifetime, 235-240 ps. This indicates that the concentrations of the vacancy-type defects for the as-synthesized CuIn_1-xGa_xSe₂ samples are greater than the saturation trapping limit (10¹⁸ cm^-3). Moreover, results of the PAL measurements and the theoretically calculated positron lifetimes indicate that Cu-Se, In-Se and/or Ga-Se are the dominant vacancy-type defect for all studied range of Ga. Also, the results show that the vacancy-type defect concentrations of samples with Ga content of 0.6 and 0.82 are reduced compared with that for zero-Ga content sample.

Various dc conduction mechanisms and high frequency (1MHz up to 3 GHz) dielectric properties have been studied for the particulate and 0-3 core shell composites. X -ray diffraction has been used to identify the structural properties. Tetragonal and cubic structures for PZT and ferrite respectively were appeared either in the pure form or in composites form. The microstructures have been investigated by TEM and particle size distribution was calculated. The microstructure plays a significant role in the electric properties. Dc resistivity vs. temperature measurements were implemented by using 'two probe' method. The room temperature resistivity was large in core shell in comparison with composite due to the unique microstructure of the core shell that enhances the interfacial disability of motion of carriers and increasing the carriers hopping path. Moreover, dc electric conduction mechanisms for all investigated samples have been determined. Curie temperatures for ferrimagnetic and ferroelectric phases were the transition points between the conduction mechanisms. Curie temperature of ferrites remarkably increased in the C.S. and composite. Finally, Dielectric and ac resistivity measurements were measured at room temperature. The dielectric constant (ε') was enlarged in the core shell rather composite while the tangent loss was reduced. These appreciable enhancements could be useful in the high frequency applications.

The microstructure of the particulate composite vs. 0-3 core shell composite has a noticeable effect on the structural, interfacial and magnetic properties. Both particulate composite and 0-3 core shell composite have the same components. X-ray diffraction has been used for all samples to identify the structural properties. The microstructures have been investigated by TEM and particle size distribution was calculated. By using IR Spectroscopy, vibrational bands have been exploited to recognize the interfacial interaction. Magnetic hysteresis curves have been measured by VSM. The relative permeability vs. temperature experiment have been measured and Curie temperatures have been determined.

In the last two decades, several applications became more dependent on the nonlinearity phenomena in glasses, for example: laser glass has low nonlinear refractive index (n₂), while higher values serve in optical switching. In this study, Vanadium-Lithium-Phosphate glass samples [V₂O₅-Li₂O-P₂O₅] were prepared by the melt-quenching technique. The amorphous structure of these glasses is examined by XRD analysis. The recorded reflectance and transmittance were investigated over the range from 200 to 2500 nm for the five samples. The two parts of the calculated refractive indices are estimated via an analytical technique. The dispersion parameters, such as Sellmeier gap energy, dispersion energy as well as Abbe's number, were deduced. From the obtained results, the parameters for absorption dispersion, namely: the optical energy gaps for indirect transition as well as the Urbach energy were extracted. Moreover, the other parameters such as: the molar refractivity, the reflection loss and density are calculated. The measured optical parameters were found to vary nonlinearly with increasing vanadium oxide (V₂O₅), in the presence of Li₂O in the phosphate matrix. In the aim of enhancing the performance in this glass system, the effects of ascending doping with a transition metal oxide (V₂O₅) on both the predicted nonlinear and the linear optical parameters, are investigated and analyzed.

Abstract.The as-prepared Mn_0.5Cd_xSr_0.5-xFe₂O₄ nanocrystals, (x = 0, 0.1, 0.2, 0.3, 0.4, 0.5), were synthesized by the one-beaker and smart co-precipitation strategy, thereafter nanocrystals were well-characterized by X-ray diffraction (XRD), FT-IR spectra, higher resolution transmission electrons microscopy (HTEM) and vibrating Nano-samples magnetometry (VSM) strategies. XRD investigation proved the evolution of the single-phase spinel structure for all nano-spinels. The crystallite size R values ranged from 16.05 – to – 32.1 nm, with declining behavior with Cd²⁺ cationic ratio x. FT-IR absorption spectrum displayed 6-absorption bands that were related to their principle sites and main bonds. The elicited parameters were influenced by the Cd²⁺ cations replacement instead of Sr²⁺ cations. Magnetic merits proved the soft-magnetic features for all these nanocrystals, whereas, all the magnetic parameters were influenced by the replacement process with Cd²⁺ cations. HTEM images exhibited aggregations in these ultrafine nanoparticles. The nanoparticles sizes Z ranged from 20 – to – 35 nm a little greater compared with crystallite sizes R.

The tiny as-prepared CoLa_xFe_2-xO₄ nanoferrites, (x = 0, 0.02, 0.06, 0.1, 0.15, 0.2), nanoparticles were fabricated by the one-way and energy-efficient co-precipitation route, and discriminated by the X-ray diffractometry (XRD), FT-IR spectra, thermographometry and vibrated Nano-sample magnetometry (VSM) strategies. XRD investigation disclosed the emergence of the spinel's mono-phase for all nano-crystals. Crystallite size R values ranged from 23.19 – to – 34.77 nm, with rising demeanor with x. IR spectra displayed four absorption bands that were related to their principle sites and main bonds. All the educed operators' alterations are assigning to La³⁺ cations replacement instead of Fe³⁺ cations. Thermal testing of these nanoferrites exhibited 3-distinguished stages of burning practicability. Picked saturated magnetization Ms of these Nano-spinels was declined versus x, whilst coercive field Hc raised as well as the squareness Mr/Ms rise with La³⁺ cationic ratio x.

The (XRD) patterns of the samples Ni_0.5Zn_0.5Fe₂O₄ in the form of powder were prepared using the ball milling technique for 41, 67 and 90 hours and were annealed at 1073, 1273 and 1373 K and (Poly vinylidine Fluoride) (PVDF) and composite samples of x% Ni_0.5Zn_0.5Fe₂O₄/PVDF, (x% = 5, 10, 15, 20 and 25%) have been studied. The α phase decrease and β-phases increase by increasing the ferrite content suggesting less crystallinity producing an amorphous structure of PVDF at x = 25% ferrite where as β PVDF nucleates in the composites The electric polarization increases by increasing NZF content. The transition from ferromagnetic (order state) to paramagnetic (disorder state) occurs at Curie temperature T_C (600K). The DC resistivity is nearly constant from 153k to 286k for all composite samples and then decreases at high temperature. The behavior of dielectric constant and dielectric loss was measured in the temperature range from 200K to 700K. With the increase of magnetic content, the saturation magnetization (M_s) value of the composites also increases.

This work presents the effect of particle shape on the magnetic and optical properties of Ni-Co nanoferrite (NCF). Two series of different preparation methods were used to obtain two different shapes of Ni_xCo_1-xFe₂O₄ where x=0, 0.25, 0.5, 0.75 and 1. Sol gel was the first method used to synthesize NCF with citric acid as a fuel and the second series was synthesized by hydrothermal route and the fuel was oxalic acid. Structural characterization for NCF nanomaterials was carried out by X-ray diffraction (XRD), Energy Dispersive Spectroscopy (EDS) and Transmission Electron Microscope (TEM). Magnetic parameters were determined from Vibrating Sample Magnetometer (VSM) for all samples and it is noticed that the values of M_r and M_r/M_s are greater in nanorod series than nanosphere series. RLC Bridge was used to obtain the Curie temperature of the polycrystalline nanomaterials by the variation of relative permeability with increasing temperature. Values of direct and indirect band gaps were determined from double beam spectrometer using Diffused Reflectance Spectroscopy (DRS) measurements. It was found that changing particle shape could change the cation distribution, magnetic and optical properties of NCF nanoparticles.

Graphene, as being transparent material attempts for mid-infrared absorption. In this work, we theoretically show that excitation of localized Mid-IR plasmon resonance (LSPR) is possible in graphene single layer patterned with nano-holes. By designing graphene patterned with nanoscale holes of specific dimensions, LSPR is excited at particular wavelength, leading to noticeable absorption. We use finite difference time domain to investigate the excitation of LSPR in nano-meshed graphene at the mid IR wave length range with absorption value reaching 35 %. We also proved the excited plasmon localization at the holes' edges through mapping the electromagnetic field distribution

Ni_xCd_1−xFe₂O₄ (x = 0.0, 0.1, 0.2, 0.3, 0.4, 0.5) nanoferrite powder were synthesized using flash auto combustion method. The studied powder was characterized by X-ray diffraction (XRD), which was used to determine the structural properties. The effect of addition dyes (perylene dye and thiophene dye) on the optical properties of Nickel Cadmium ferrite has been investigated. The optical study UV-Visible is used to calculate the band gap energies. From Tauc's plot, it can be seen that the band gap energy of the samples is decreasing with increase in nickel content for both dyes, indicating the enhancement of the optical of ferrite.

The spinel Nano-ferrite system NiCr_xFe_2-xO₄ (where x=0.0, 0.2, 0.4, 0.6, 0.8 and 1.0) have been prepared using flash auto combustion method. The XRD pattern confirms the formation of spinel Ni-Cr ferrite for the as-prepared samples. Electrical properties of as- prepared samples such dielectric constant and AC resistivity were studied in the temperature range (288- 773 K). It was observed that the AC resistivity increases by increasing Cr content and decreases by increasing frequency. The DC electrical resistivity was found to increase by increasing Cr content from 25*10⁶ to 136*10⁶ Ω.cm, whereas it was found to decrease with increasing temperature. VSM was used to study the magnetic properties of Ni-Cr ferrite at room temperature. It was found that, with increasing Cr content the (Ms) saturation magnetization decreased from 28 to 3 emu/g whereas coercivity increased from 188 to 666 (G).The magnetic moment of the system and Curie temperature decreased by increasing Cr substitution.

A Series of ferrite samples Ni_0.1 Cu_0.2 Zn_0.7-x Mg_x Fe₂O₄ (where x = 0, 0.15, 0.25, 0.35, 0.45, 0.55 and 0.7) were synthesized using auto combustion flash method. The samples were annealed at 600 °c for 2 hours to eliminate the foreign phases of the constituent nitrate and internal stress. The purity of phase structure was confirmed by x-ray diffraction. Some structural and microstructural parameters like porosity, x-ray density, crystallite size and lattice constant were deduced from x-ray. Scanning electron microscope (SEM) analysis reveals that the grains are separated by pores in all samples and the average grain size decreases with increasing Mg content. Magnetic properties such as coercivity (H_c), saturation magnetization (M_s) and retentivity (M_r) were measured from M-H loops. The magnetization curves were characterized by low coercivity indicating that our samples are soft magnetic material. Both saturation magnetization and coercivity increase by increasing Mg ions where M_s reaches maximum value at x = 0.35 then decrease for higher Mg content.

The sustainability of any system can be explained Carnot principle. The manmade devices / systems are consuming natural resources mass, R, combination of air, water and fuel. After proper operations, the devices / systems rejected waste mass, W into the eco-system. Applications of Carnot principle indicated that ecological efficiency (η_Eco) in this case is $[1-\frac{W}{R}]\times 100 \%$ and if W is not digested or recycled through natural system, then η_Eco has a tendency towards zero and will trigger back to the ecological system and raised the question for sustainability of eco-systems. One of the consequences of W on the eco-system is the smog formation at the beginning of winter morning over the urban surroundings. The smog causes major problems in respiration, visibility and ultimately affects mobility. The possible reason behind smog formation is the condensation of gas and particulates at dawn time emitted from burning of bio-mass and fossil fuels. The condensation gets delayed due to the urban heat islanding (UHI) effect generated by the built-in-systems. The condensation diffuses with raise in ambience temperature from sun shine. This paper delves an analysis on the cause and effect of UHI and impact of clean mobility in diffusing the smog effect.

In the present study, the fast spectrum transmutation experimental facility (FASTEF) core that considered for the MYRRHA reactor is modelled using Monte Carlo MCNPX code. The effect of changing the type of material and radius of the cylindrical target source as well as the energy of the proton beam on the final production of neutrons and the subcritical multiplication of the system are evaluated. Subcritical models of the investigated reactor have been numerically investigated as well. six target materials; uranium (U), lead-bismuth eutectic (LBE), tungsten (W), lead (Pb), bismuth (Bi), and copper (Cu) are used with varying target radii from 3.5 to 20 cm. The beam energy is varied from 0.2 to 2.0GeV. The present study depends on numerical calculations of the subcritical multiplication factors and the efficiency of the external source using MCNPX code. The obtained results revealed that the favourable target material, radius, and beam energy can be precisely determined.

Dye-sensitized solar cells (DSSCs) which have a polymer electrolyte added to with various function groups were studied to determine the effect of their composition on the efficiency of the solar cell. Four function group polymers got employed, those groups are polymethylmethacrylate (PMMA), polyvinyl acetate (PVA), polyethylene oxide (PEO) and polyacrylonitrile (PAN). The iodine salt cation is caged by the function groups which cause a positive shift in the dye HOMO level and result in a deceleration in the recombination rate more than that of ordinary iodine electrolyte. The polymer electrolyte ionic conductivity improves the rate of the dye regeneration to make it faster than ordinary iodine as well. Adding pyridine to electrolyte solution makes the conduction band of the TiO₂ more negative leading to an increase in the open circuit voltage (V_oc). The photo generated current (J_sc) is increased by the employed configureuration, subsequently, the solar cell photovoltaic efficiency is enlarged. PVA is with highest efficiency at 8%, unlike the rest of the polymers which show lower efficiencies.

The efficiency of carbon-based dye sensitized solar cells (DSSCs) is improved by mixing titania with graphene (GR) sheets. The composite films of GR sheets and TiO₂ were characterized using field emission scanning electron microscopy (SEM). The grinding of GR with TiO₂ leads to smaller size TiO₂ nanoparticles which increases their surface area. The photovoltaic efficiency varied with the mixing ratio giving the highest efficiency at a ratio of 1 wt. % of GR to TiO₂. The increase in the photovoltaic efficiency is more than doubled the one without GR under the same conditions. Mesoporous carbon from candle flame and N3 dye were used instead of Pt and N719 dye to reduce the cost.

The fluorescence and light absorption and dielectric characteristics of wheat are studied to investigate the influence of gamma exposure on germination, morphological and physical properties of wheat plant. Wheat grains were irradiated at 0, 1.5, 2, 2.5, 3, 5, 7 and 10 krad. The obtained results indicated that, pronounced increase in germination rate, plant height, and root length were obtained at 2.5 krad treatment. Furthermore, those characteristics were evaluated for chlorophyll at different doses given to wheat grains. The analysis of these spectra indicates that the maximum emission and absorption obtained at 2.5 krad gamma irradiation dose. Moreover, the dielectric properties and the electric conductivity of the different irradiated samples were determined in the frequency range 20 Hz- 100 kHz. The obtained data were treated precisely to determine the dielectric constant and the Ac conductivity that easily describe the plant growth. The predictions of the obtained results give further support for the 2.5 krad to be the best dose to stimulate the plant growth features.

GATE/GEANT4 code-based Monte Carlo simulations have been conducted and validated for the purpose of studying the mass attenuation coefficient of xR_mO_n: (100-x) SiO₂ glass systems (where R_mO_n are Bi₂O₃, PbO and BaO, with 30 ≤ x ≤ 70 % by weight) at 662 keV. The results came in agreement with the ones previously obtained through WinXcom program. Consistency between simulation and experimental results is confirmed by using χ² test. The obtained results suggest the validity of using GATE for estimation of mass attenuation for different material compositions at different energies. This specific study recommends GATE simulation code as a suitable tool to investigate materials in the field of radiation shielding as an alternative to the experimental method.

The effect of the BaO addition of to aluminum, lead borate in a series of (BaO)x (B₂O₃)60-x (Al₂O₃)10 (Li₂O)10 (PbO)20 glasses where x = 0 to 50 weight% have been studied through their shielding, mechanical, thermal and chemical properties. The physical parameters such as molar volume (V_m), density (ρ), and oxygen packing density (OPD) were evaluated and discussed. Moreover, the thermal stability of the investigated system increases with BaO content. The present study proved that each of the plasma nitriding treatments of the samples and/or increasing Ba content greatly improved their ability to resist scratching and corrosion. Therefore, the obtained results are candidates for the present glass system to be effectively used as a protective shield against nuclear radiations in many advanced domains.

The electro-slag re-melting technique was used to produce locally two standard stainless steel samples, AISI304L and AISI316L. The shielding properties of both neutrons and gamma radiations were determined using He-3 and NaI(Tl) detectors. A mixture of hydrogen and nitrogen gases (1:1) was used to investigate the effect of rf plasma surface engineering on properties of austenite stainless steel AISI304L which is used in many parts of nuclear power plant. The X-ray diffraction technique was used for recognizing the structural phases on the studied austenite stainless steel samples. The rf plasma process was performed for half an hour at stable gas pressure and water cooling rate. As a result of the rf plasma surface engineering process, enormous enhancement was achieved in surface microhardness, tribological properties and remarkable increase in the absorption cross section for slow neutrons. Moreover, the gamma ray attenuation properties for the HN304L sample is to great extent comparable with those of AISI316L and AISI304L austenite stainless steel samples. As a consequence, the obtained results give a further support in favor of the rf plasma engineering in the nuclear domain.

The crab carapace is the shell covering the body. The present work provides an overview of the use of electron paramagnetic resonance (EPR) after reviewing the status of the structure and composition of the crab carapace shell using XRD and FTIR techniques. Crab samples were cleaned from soft tissue, dried and irradiated with Co-60, with doses up to 30 kGy. EPR spectra of native as well as irradiated crab carapace samples were recorded and analyzed.

FTIR results confirm the XRD results of the analyses done on the crab carapace shell. They show that, the main composite of the shell is calcium carbonate. The EPR results show that, the amplitude of the CO₃ signals increased with increasing the absorbed dose. Identification of the irradiated carapace samples was concerned with the detection of the EPR spectra for g-values which are attributed to those in the coaxial CO3 free radical.

The aim of the present work is studying the effect of radiation and investigation of some physicochemical properties of crab carapace shells using XRD, FTIR spectroscopy. Also, evaluation of the induced free radical in the crab carapace due to irradiation using the EPR technique.

Three nominated types of table salt samples are obtained from different sources: "cok" rooks table salt, "sal" red sea marine table salt, "Dr.salt" table salt with low sodium content prepared for hypertensive patients to procedure in this work labeled C, S and D respectively. Characterization of the table salt types using X-ray diffraction (XRD) analyses and the energy dispersive X-ray (EDX) analysis was carried out. EDX analyses show a difference in sodium and chloride content percentage atomic ratio between the three salt types. Also, potassium is apparent in the salt type D. The positions of each diffraction peak maximum intensity were obtained and compared with the corresponding peak in the database. Also, to discriminate the diffraction peaks of the impurities.Samples were irradiated with gamma source using Co⁶⁰ at room temperature. Electron spin resonance (ESR) has been studied in the three different commercial table salt samples. The aim of the present study is to investigate the sensitivity of the naturally occurring table salts to gamma radiation, using the ESR technique The ESR results represent the signal intensity of the salt types C is higher than S than D. The results also indicate that, the ESR intensity of the table salt and the sensitivity to gamma radiation increases with increasing the percentage of sodium and also some other impurities in each content type.