Rayleigh Ratio Research Articles

Toward the authentication of wines of Itata valley denomination of origin through total reflection x-ray fluorescence (TXRF) method for testing adulteration. A novel valuable tool by using Compton/Rayleigh scattering signals in wines

The evaluation of wine adulteration is often a cumbersome process not exempt from multiple difficulties. In this work, a valuable methodology to rapidly assess wine adulteration was used. Harnessing the ratio of Compton and Rayleigh scattering signals obtained in TXRF (total reflection X-ray fluorescence). The Compton/Rayleigh signal ratio as a sensitive way to estimate the average effective atomic number (Zeff) of a sample was used. Thus, any addition made into the wine, would cause a change in its Zeff which could be detected by TXRF. Non-adulterated and adulterated wines were selected and its Zeff was estimated. The method was developed using X-ray excitation Molybdenum tube. Deconvolution of independent Compton and Rayleigh signals was performed by non-Gaussian and Gaussian curve resolution methods, and the area ratio was evaluated. A calibration curve for Compton/Rayleigh signal ratio versus Zeff was established and wine adulterated samples were tested in a Zeff range between 4.3 and 7.2. Wine adulteration was detected in all cases. The method is simple, fast, sensitive, precise and non-destructive. It procedure is usefulness as an important tool for wine industry and for the maintenance of origin and quality of wines.

ON AN OPTIMIZATION PROBLEM FOR A PRESTRESSED PLATE WITH VARIABLE STIFFNESS

Most studies in the field of optimization problems in the mechanics of the deformable solid body are aimed at finding the optimal shape of structural elements, which most often leads to the search for the optimal distributions of geometric characteristics for the considered objects in order to ensure reducing the objects? weight and improve their strength characteristics. At the same time, with the advent of modern materials with variable physical and mechanical properties, new relevant branches arose in the optimization problems, as well as the inverse problems on the reconstruction of non-uniform variable characteristics. In this study, the problem of steady-state oscillations of a prestressed inhomogeneous round elastic plate in an axisymmetric formulation is considered. Variational and weak problem statements are presented. The case of free oscillations of a plate simply supported along the contour is investigated; it is shown that the eigenvalue problem is self-adjoint and quite definite. The problem of finding the optimal distribution of the plates? elastic modulus and the corresponding oscillation shape in order to maximize the first natural frequency is considered. An isoperimetric condition for the variable stiffness function is proposed. Based on the Rayleigh energy ratio, the minimum principle for the first eigenvalue and the corresponding eigenfunctionis formulated. On the basis of the variational principle, using the constructed Rayleigh ratio, the optimality condition is formulated, and an explicit representation is obtained for the functions of the optimal oscillation shape and optimal stiffness, taking into account the initial radial stretching or compression of the plate. The range of possible values for the initial stress is determined. The results of solving the problem via constructing optimal inhomogeneity laws for the stiffness function in the class of smooth functions in the considered range of changes in initial stresses are obtained and analyzed.

An alternative approach for determining the effective atomic number of some compounds: Monte Carlo study

Researchers have been searching for different methods to determine the effective atomic number of materials for many years. Therefore, there are many methods in the literature to determine the effective atomic number theoretically or experimentally. While theoretical methods neglect some parameters, such as the momentum transfer parameter, photon energy, or scattering angle, experimental methods have incommodious processes. The main goal of this study is to provide a practical simulation method that is both as realistic as experimental results and as easy as theoretical methods. The method considers all these parameters compared to other theoretical methods and transfers them to the virtual environment. In this study, Rayleigh and Compton scattering peaks of 60 pure elements (in the range 20< Z <80) were determined. Rayleigh and Compton peak ratios were correlated with their atomic numbers. The proposed method is available for any energy or scattering angle. Six different compounds (WC, W65Cu35, SnAg, Fe54Co17Ni29, Pd94Cr6, Cu60Zn40) were selected from different atomic number regions (such as low, medium, and high regions). It is important to note that any material (compound or mixture) could be selected. Validation of the method has been performed via different methods commonly used in the literature. It is observed that the results of this method are in good agreement with other methods in the literature. We are expecting that the proposed method will provide great convenience and guidance to researchers in this area.

Magneto-double-diffusive natural convection and irreversibility analysis of a nanofluid flowing in an annular concentric space

In the present article, magneto-double-diffusive density driven convection accompanied by an entropy optimization analysis of Al2O3-water nanofluid filled in a horizontal coaxial annular space is numerically addressed. The double-diffusive natural nanofluid flow which is produced due to the maintaining of constant and different temperature and solute on the inner and outer cylinders is affected by a uniform vertical magnetic field. Dimensionless governed equations which are developed through law of conservation of mass, momentum, and energy are numerically solved via finite volume approach, and parametric control analysis is developed. By using Corcione empirical correlations considering the Brownian diffusion of 4% of Al2O3 nanoparticles in water, the thermal conductivity and viscosity of the mixture nanofluid are determined. Results are performed and interpreted in detail for wide range of relevant variables: Rayleigh (102 ≤ Ra ≤ 105), Hartmann (0 ≤ Ha ≤ 30), Lewis numbers (0 ≤ Le ≤ 10), and Buoyancy ratio (−4 ≤ N ≤ 4) to evaluate the double-diffusive convective nanofluid flow, heat and solute transfer rates as well as entropies produced in the system.

Thermal Diffusivity and Fick Diffusion Coefficient in Mixtures of Hydrogen and Methane by Dynamic Light Scattering

Mixtures of hydrogen (H2) and methane (CH4) are given in many technical applications where accurate thermophysical property data are required for the design and optimization of corresponding processes. This work evaluates the accessibility of the thermal diffusivity a and the Fick diffusion coefficient D11 in gaseous binary mixtures of H2 and CH4 by dynamic light scattering (DLS). The investigations are performed at temperatures T and pressures p of (293, 333, 363, and 393) K and (5, 10, and 15) MPa with varying CH4 mole fractions x_{{{text{CH}}_{{4}} }} of (0.05, 0.3, 0.6, and 0.8). For all thermodynamic states investigated, only one hydrodynamic mode was observable by DLS. The assignment of the single related diffusivity to either a, D11, or a mixed diffusivity Dmix representing both a and D11 is performed by considering D11 calculated by the Chapman–Enskog kinetic theory, experimental D11 literature data, a predicted by using two different approaches, and calculations of the so-called Rayleigh ratio. The findings indicate that DLS gives access to a at high x_{{{text{CH}}_{{4}} }}, D11 at low x_{{{text{CH}}_{{4}} }}, and Dmix at x_{{{text{CH}}_{{4}} }} ≈ 0.3. All data are summarized in the form of correlations providing a and D11 as a function of T, p, and x_{{{text{CH}}_{{4}} }}.

Метод синтеза антенной решетки со сниженным уровнем боковых лепестков при наличии отказов каналов и модулей

A method of matrix amplitude-phase synthesis of a flat antenna array with module failures according to the requirements for the envelope of the side lobes is proposed. The problem is reduced to finding the extremum of the Rayleigh ratio of two Hermitian forms, one of which takes into account the requirements for the envelope of the side lobes and is positively determined. The proposed method differs from the known ones by an iterative procedure for searching for a weight function for the formation of integral coefficients of a positive-definite Hermitian matrix of the Rayleigh relation. In the proposed method, failure accounting is carried out using two identical diagonal matrices, single values of these matrices correspond to serviceable elements, and zero – faulty ones. The condition of positive definiteness of the quadratic form, taking into account the requirements for the envelope of the side lobes, is achieved by weighing the diagonal coefficients of the matrix. As a result, when changing the structure of failures of elements and modules of the antenna array, it is not necessary to adjust the dimension of the problem. It is shown that in the presence of module failures, the level of the side lobes of the volumetric directional pattern increases significantly. At the same time, the use of conventional weight signal processing of antenna array channels with a reduced level of side lobes leads to a loss of power of the signal component at the output of the antenna array with a slight decrease in the level of side lobes. It has been found that the application of the proposed method makes it possible to achieve a noticeable decrease in the level of side lobes with controllable losses of the signal-to-noise ratio at the output of the antenna array.

Effects of hollow skeleton on melting process in copper foam

The compositing of porous medium and phase change material is an effective way to improve the heat transfer performance of solid-liquid phase change energy storage system. In this paper, we reconstruct the three-dimensional numerical structure of the copper foam by using the micro computed tomography, and then conduct the pore-scale numerical simulation of the melting process in a cubic cavity filled with the phase change material comprised of the copper foam via the lattice Boltzmann method. The effects of the hollow skeleton on the melting process are discussed in detail under different Rayleigh numbers and ratios of thermal conductivity of the copper foam to that of the phase change material. The results show that the hollow skeleton copper foam possesses a lower average Nusselt number along the left wall at the early stage of the melting process, a slower melting rate, and a higher energy storage efficiency than the solid skeleton copper foam. Comparing with the skeleton region of the copper foam, the heat transfer rate entering the cubic cavity through the hollow region of the skeleton is almost negligible. Because of the competition between heat conduction and natural convection, the heat transfer enhancement efficiency of copper foam first increases, then decreases, and then increases again with the increase of the Fourier number. When the Rayleigh number decreases, the energy storage efficiency increases, and the natural convection also weakens. Meanwhile, the fluctuation of the heat transfer enhancement efficiency decreases as the Fourier number increases, and the gap of the heat transfer enhancement efficiency between the hollow skeleton copper foam and the solid skeleton copper foam becomes smaller. When the ratio of the thermal conductivity of the copper foam skeleton to that of the phase change material increases, the energy storage efficiency is relatively high at the early stage of the melting process but becomes relatively low when the melting process is completed. With a larger thermal conductivity ratio, the heat transfer rate entering the cubic cavity through the skeleton region of the copper foam becomes dominant, which reduces the effect of the hollow skeleton on heat transfer, and thus the gap of the heat transfer enhancement efficiency between the hollow skeleton copper foam and the solid skeleton copper foam becomes relatively small.

Entropy generation through porous cavity containing nanofluid and gyrotactic microbes

This research explored the influences of entropy generation on bioconvected nanoliquid flow through the porous cavity filled with nanofluid and gyrotactic microbes. The porosity term in the momentum equation is summarized by the implementation of Darcy’s formula through Boussinesq estimation. The novelty of this study is to investigate entropy generation in cavity by augmenting the convection generated by the phenomenon of Brownian motion, thermophoresis of nanofluid flow and the bioconvection due to swimming of microorganisms. The governing partial differential equations (PDEs) are highly nonlinear and are nondimensionalized through the suitable similarity constraints. The transformed PDEs are tackled via implementation of finite difference method (FDM). The reaction of entropy generation and Bejan number against various quantities like bioconvection Rayleigh number ([Formula: see text]–100), Rayleigh number ([Formula: see text]–100), Peclet number ([Formula: see text]–0.9) and ratio of buoyancy ([Formula: see text]–1) are reported and visualized. The entropies by theliquid friction, heat transportation, mass transmission and microorganisms are focused. Upsurge in Nr (0.3–0.5) and Pe (0.1–0.15) accelerated the maximum of entropy due to microorganism by 7% and 44%, respectively. Here, an increment in Ra, Rb, Pe and Nr affects the distribution pattern of total entropies and Bejan number consistently. The higher Lewis number caused a decrement in the total entropy by liquid friction.

Conformation and Structure of Hydroxyethyl Cellulose Ether with a Wide Range of Average Molar Masses in Aqueous Solutions

The solution properties of a water-soluble chemically modified cellulose ether, hydroxyethyl cellulose (HeC), were examined using static light scattering (SLS), dynamic light scattering (DLS), small-to-wide-angle neutron scattering (S-WANS), small-to-wide-angle X-ray scattering (S-WAXS) and viscometric techniques at 25 °C. The examined HeC samples had average molar substitution numbers ranging from 2.36 to 2.41 and weight average molar masses (Mw) that fell within a wide range from 87 to 1500 kg mol-1. Although the relationship between the determined radius of gyration (Rg) and Mw was described as Rg ∝ Mw~0.6, as is observed usually in flexible polymer solutions in good solvents, the observed scattering vector (q) dependencies of excess Rayleigh ratios were well interpreted using a rigid rod particle model, even in high-Mw samples. Moreover, the ratios of the formed particle length (L) evaluated assuming the model for rigid rods to the determined Rg showed the relationship LRg-1 ~ 3.5 irrespective of Mw and were close to those theoretically predicted for rigid rod particle systems, i.e., LRg-1 = 12. The observed SLS behavior suggested that HeC molecules behave just like rigid rods in aqueous solution. As the L values were not simply proportional to the average molecular contour length calculated from the Mw, the chain conformation or structure of the formed particles by HeC molecules in aqueous solution changed with increasing Mw. The q dependencies of excess scattering intensities observed using the S-WANS and S-WAXS experiments demonstrated that HeC molecules with Mw less than 200 kg mol-1 have a diameter of ~1.4 nm and possess an extended rigid rod-like local structure, the size of which increases gradually with increasing Mw. The observed Mw dependencies of the translational and rotational diffusion coefficients and the intrinsic viscosity of the particle suspensions strongly support the idea that the HeC molecules behave as rigid rod particles irrespective of their Mw.

Measurements of Rayleigh ratios in linear alkylbenzene

This paper describes a new experimental setup designed for the direct measurement of the Rayleigh ratio and Rayleigh scattering length for linear alkylbenzene, a solvent commonly used in liquid scintillator detectors for neutrino experiments. Using the new approach, the perpendicularly polarized Rayleigh ratio was determined to be (4.52 ± 0.28) × 10-6 m-1 sr-1 at 405nm and (3.82 ± 0.24) × 10-6 m-1 sr-1 at 432nm, and the corresponding Rayleigh scattering length was LRay = 22.9 ± 0.3(stat.) ± 1.7(sys.)m at 405nm and LRay = 27.0 ± 0.9(stat.) ± 1.8(sys.)m at 432nm. These results are consistent with both previous results determined using other experimental strategies and theoretical predictions.

Thermal hydraulic characteristics of silicon irradiation in a typical MTR reactor

Abstract In this work, a three-dimensional study is conducted for silicon ingot irradiation facility in a typical MTR reactor. The silicon ingot heat generation is allowed to change around its nominal value in the range of 0.25, 0.5, 0.75, 1.0, and 1.25 W/g. The dimensionless clearance ratio ζ between the ingot and the outer casing is changed for values of 0.01, 0.05, 0.1, 0.15, and 0.2. The computational fluid dynamics code ANSYS FLUENT is employed to carry out these calculations. The temperature profile inside the silicon ingot during irradiation is of significant importance for uniform doping. Therefore, the impact of Rayleigh number and dimensionless clearance ratio ζ on the radial and axial temperature profiles through the ingot is reported. A best estimate correlation for the silicon irradiation facility global Nusselt number in terms of Rayleigh and dimensionless clearance ratio is presented. The dimensionless clearance ratio ζ value of 0.05 gives the best thermal hydraulic performance. Comparison with the available experimental correlations in the literature shows good agreement.

The Role of Mixed Convection and Hydrodynamic Dispersion During CO2 Dissolution in Saline Aquifers: A Numerical Study

AbstractDissolution trapping plays a significant role in CO2 geological storage. When CO2 dissolves in aquifer brines, the aqueous solution is heavier than the underlying resident brine. This results in convective instability in the form of CO2‐rich fingers, which accelerates dissolution. It was recently shown that background flow affects CO2 dissolution by suppressing the development of convective fingers. However, there was a discrepancy between computational results and measurements, with the computational results demonstrating a decrease in the dissolution rate and the laboratory measurements showing no significant effect. Here, we attempted to understand this difference by exploring the relations between the transport mechanisms that facilitate convective mixing. We investigated the role of background flow by using numerical simulations that were validated by laboratory measurements and analytical solutions. Simulations were generated for the same porous medium and fluid pair used in the experiments, keeping the Rayleigh number constant, while changing the background velocity and the Peclet number. Studying the flux components revealed three distinct regimes characterized by the Peclet to Rayleigh ratio Pe/Ra. When Pe/Ra &lt; 0.77, natural convection dominated, and dissolution remained approximately constant. When the background flow was large (Pe/Ra &gt; 2), dissolution was controlled by pure forced convection and increased with Pe/Ra. In the intermediate range (0.77 &lt; Pe/Ra &lt; 2), both natural convection and forced convection were important.

Effect of inclination angle on bioconvection in porous square cavity containing gyrotactic microorganisms and nanofluid

The current article investigates the effect of inclination angle on thermo-bioconvection within the porous-square shaped cavity filled with gyrotactic type microorganisms and nanofluid. The Darcy law with Boussinesq estimation is used for the momentum equation in porous media. The transformed governing equations are solved by Galerkin’s method of finite elements. The effect of inclination angle in the square cavity is interpreted by varying the angle from [Formula: see text] to [Formula: see text]. The effect of inclination on different quantities, for instance, Rayleigh number, bioconvective Rayleigh number, Peclet number, Brownian motion, heat source/sink, and ratio of buoyancy, is discussed. Further, the mean quantities of Nusselt number [Formula: see text], Sherwood number [Formula: see text], and density number [Formula: see text] are analyzed at vertical walls. A quantitative outcome of the study is that the maximum values of [Formula: see text], [Formula: see text], and [Formula: see text] are found for the angle [Formula: see text] and [Formula: see text].

Temperature Dependence of the Rayleigh Ratio for Toluene: Thermoresponsive Polymers Characterization

AbstractBenzene and toluene are commonly used reference substances for static light scattering (SLS) measurements. However, due to the appearance and wide availability of solid‐state lasers with various wavelengths, there is a need for data on the Rayleigh ratios for references at various wavelengths. Thermoresponsive polymers, which are widely researched now, can have lower critical solution temperature (LCST) values very close to the human body temperature (30–36 °C). Such polymers can be used to develop efficient means for targeted drug delivery. In this paper, we report how to accurately determine the absolute molecular weights of thermoresponsive polymers by the SLS method. This is especially important when the LCST value of a polymer is close to the room temperature (at which SLS measurements are usually taken), which can lead to overestimated results due to the aggregation of macromolecules. So, it is necessary to carefully select the measurement temperature and, accordingly, data are needed on the temperature dependence of the Rayleigh ratios for a reference sample. The Rayleigh ratios and depolarization factors, ρu and ρv, were first determined for toluene within a wide temperature range (10–50 °C). The temperature dependencies of these parameters were shown to be linear in the whole range investigated. Temperature coefficients for the calculation of the Rayleigh ratios at different scattering geometries were obtained. The particular importance of choosing the optimal measurement temperature when determining the molecular weights of thermoresponsive polymers with low values of LCST using the static light scattering method was demonstrated.

Newton's method for the eigenvalue problem of a symmetric matrix

Newton's method for calculating the eigenvalue and the corresponding eigenvector of a symmetric real matrix is considered. The nonlinear system of equations solved by Newton's method consists of an equation that determines the eigenvalue and eigenvector of the matrix and the normalization condition for the eigenvector. The method allows someone to simultaneously calculate the eigenvalue and the corresponding eigenvector. Initial approximations for the eigenvalue and the corresponding eigenvector can be found by the power method or by the reverse iteration with shift. A simple proof of the convergence of Newton's method in a neighborhood of a simple eigenvalue is proposed. It is shown that the method has a quadratic convergence rate. In terms of computational costs per iteration, Newton's method is comparable to the reverse iteration method with the Rayleigh ratio. Unlike reverse iteration, Newton's method allows to compute the eigenpair with better accuracy.

Importance of multiple slips on bioconvection flow of cross nanofluid past a wedge with gyrotactic motile microorganisms

In the current article, a mathematical model is developed to visualize the flow of non-Newtonian magneto cross nanofluid with mass and heat transport rates having activation energy, motile microorganisms and bioconvection over the wedge. The phenomena of microorganisms is implemented to control the suspension of nanomaterials. The results of hydromagnetic are also integrated into the momentum expression. Nanofluid is developed by dispersing the nanosized particles in the regular fluid. Nanosized solid materials like carbides, ceramics, graphene, metal, alloyed CNTs etc. have been utilized for the preparation of nanofluid. Physically regular fluids have low thermal efficiency. Therefore, the nanosize particles can be utilized to enhance the thermal efficiency of the regular fluids. Nanofluids have many features in hybrid power engine, heat transfer and can be useful in cancer therapy and medicine. The constructed system is first simplified into nonlinear form by introducing similarity variables. Then obtained ordinary differential equations (ODEs) which are evaluated for numerical solution. Further, for numerical approximation, the popular bvp4c scheme built-in function in MATLAB is utilized. Reliable outcomes are achieved for the temperature, velocity, concentration and motile microorganism density profiles. Results for numerous essential flow parameters are shown via numerical outcomes and graphs. It is revealed that velocity upsurges with enhancement in mixed convection parameter while reduces for bioconvection Rayleigh and buoyancy ratio parameters. Furthermore, the volumetric concentration of nanoparticles boost up for growing estimations of activation energy parameter. The microorganisms field upsurges with larger microorganism slip parameters while reduces with the augmentation in magnitude of bioconvection Lewis number and Peclet number. The obtained numerical results are compared with the available data and found good agreement.

Fixed-flux salt-finger convection in the small diffusivity ratio limit

Salt-finger convection provides a key mixing process in geophysical and astrophysical fluid flows. Because of its small characteristic spatial scale and slow diffusive time scale, this process must be parameterized in geophysical and astrophysical models, where relations linking background gradients to fluxes are required. To obtain such relations, most authors study the dependence of temperature and salinity fluxes on fixed background gradients. Using the reduced model derived by Xie et al. [“A reduced model for salt-finger convection in the small diffusivity ratio limit,” Fluids 2(1), 6 (2017)] for salt-finger convection in the limit of small diffusivity and large density ratios, this paper considers the conjugate problem where the fluxes are fixed, but the mean gradients are permitted to adjust in response. In small domains, the fixed-flux condition leads to stable single-mode solutions, which are not achievable with fixed-gradient conditions. In large domains, with statistically steady saturated states, the relations between mean fluxes and mean gradients are identical for both sets of conditions. The fixed-flux condition provides a new perspective for understanding the resulting statistically steady states by identifying two distinct regimes with the same dissipation rate. We find that the statistically steady dynamics select the state with the smaller Rayleigh ratio Ra subject to the constraint Ra &amp;gt; 1, ensuring that the background state is linearly unstable. The fixed-flux formulation results in a more potent restoring mechanism toward the statistically steady state, with a smaller variance, skewness, and characteristic time scale than in the fixed-gradient setup. This distinctive feature can be used as a diagnostic to determine whether in situ salt-finger convection is flux-driven or gradient-driven.

Rayleigh and Rayleigh-Debye-Gans light scattering intensities and spetroturbidimetry of dispersions of unilamellar vesicles and multilamellar liposomes

Hypothesis: Since the volume fraction of the surfactant bilayer(s), of thickness db, in a vesicle and liposome is smaller than one, the dependences of the Rayleigh (R) scattering intensity and turbidity on the particle radius a are weaker than those for a homogeneous sphere, which are proportional to a3. The dependences of the Rayleigh-Debye-Gans (RDG) scattering intensity and turbidity on a are also weaker. Work done: The dependences of the effective relative refractive index on a, db, and dw (water layer thickness) were derived. The specific Rayleigh ratio Rθ** and the specific turbidity τ** for single and independent scattering were derived analytically for R and RDG scattering. Spectroturbidimetry data at 25°C for a cationic double-chain surfactant, didodecyldimethylammonium bromide (DDAB) were compared to the turbidity predictions. Findings: For R scattering, Rθ** and τ** are proportional to a2db for vesicles, and to a3dbdw+db for liposomes. For RDG and particle radii 20–1000 nm, τ** is proportional to an, where n is 2 to 0.4 for vesicles and 2 to 1.1 for liposomes. Turbidity data for DDAB vesicles are consistent with the RDG predictions, which are also used to estimate the vesicles’ sizes. RDG applies to liposomes < 800 nm and to much larger sizes for vesicles.

Diffusivities of an Equimolar Methane\u2013Propane Mixture Across the Two-Phase Region by Dynamic Light Scattering

The present contribution examines the accessibility of diffusivities across the two-phase region of an equimolar methane–propane mixture for dynamic light scattering (DLS) experiments. Heterodyne DLS experiments and theoretical calculations of the Rayleigh ratio were performed at 125 different thermodynamic states including the gas, liquid, supercritical, and the two-phase region. The present measurements document that two diffusivities can be determined simultaneously in the liquid state and saturated liquid phase for temperatures and pressures which correspond to densities larger than 1.15 times the critical density. Based on a rigorous assignment of the signals detected in this work, the slow and fast diffusivities could be associated with the Fick and thermal diffusivities. For all other thermodynamic states, a single hydrodynamic mode or signal was obtained experimentally. With the help of theoretical Rayleigh ratios as well as from the general behavior of the diffusivities as a function of temperature and pressure, the signals were identified to be related to the Fick diffusivity in the supercritical state and to a mixed diffusivity in the gas state and the saturated vapor phase. The results are discussed in connection with the behavior of the diffusivities along certain paths in the pressure–temperature projection of the phase diagram of the mixture.

Study of Cross Section Areas Ratios for Scattering Interactions of Gamma Photons in He, Fe, Fm, H2O Materials

In the research, some factors that affect the probability or the so-called interaction cross section were studied. Gamma rays interact with materials through the elastic (coherent) and inelastic (incoherent) interactions represent Rayleigh scattering and Compton scattering respectively. The energies of gamma rays in the range of (0.15 - 100) MeV for this work, and three elements were divided between the light such as Helium, a medium such as Iron, and heavy likes Fermium was selected. Also, the interaction of the H2O molecules was studied as a simulation of live tissue, which water represents more than 70% of its. In addition, the Scattering ratio of Rayleigh to Compton for these energies in chosen materials was studied to illustrate the affect of the energy amount and the material type on the domination of one of the two interactions on the other, also to determine the dependence of Compton scattering interaction on those factors, which represents an important interaction in transfer of energy to the material.The cross sections of the exploration interactions and their proportions are graphically represented to illustrate their dependence on this type of reaction to the energy of the ejected photon and the atomic number or type of target material. Rayleigh scattering to Compton scattering ratios were plotted in diagrams for each material at gamma photon energy (E = 1.25MeV) because the value of energy represents the energy rate of gamma emitted from Cobalt-60 isotope which used in many medical, research, and educational laboratories. In addition, Compton scattering ratios and as well as the Rayleigh scattering ratios in materials were plotted as a function of the sum of these probabilities. Finally, the ratios of probability for both types of scattering and for all materials to the total number of energy exploration potentials (1.25MeV) were plotted to further illustrate the relationship.