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Shock Ignition is a two-step scheme to reach Inertial Confinement Fusion, where the precompressed fuel capsule is ignited by a strong shock driven by a laser pulse at an intensity in the order of 10 16 W/cm 2 . In this report we describe the results of an experiment carried out at PALS laser facility designed to investigate the origin of hot electrons in laser-plasma interaction at intensities and plasma temperatures expected for Shock Ignition. A detailed time- and spectrally-resolved characterization of Stimulated Raman Scattering and Two Plasmon Decay instabilities, as well as of the generated hot electrons, suggest that Stimulated Raman Scattering is the dominant source of hot electrons via the damping of daughter plasma waves. The temperature dependence of laser plasma instabilities was also investigated, enabled by the use of different ablator materials, suggesting that Two Plasmon Decay is damped at earlier times for higher plasma temperatures, accompanied by an earlier ignition of SRS. The identification of the predominant hot electron source and the effect of plasma temperature on laser plasma interaction, here investigated, are extremely useful for developing the mitigation strategies for reducing the impact of hot electrons on the fuel ignition.

Microstructured foams are emerging as a promising class of targets, with applications ranging from laser-driven particle acceleration to inertial confinement fusion. To unlock their full potential, a deeper understanding of their properties, especially the changes and behavior of the microstructure under extreme conditions, is required. While recently advancing 3D printed foam targets can be observed by X-ray radiography, the microstructure in chemically produced targets is far below the spatial resolution of conventional radiography. To overcome this limitation, we apply grating-based X-ray dark-field imaging to observe structural changes in foams that are rapidly heated by laser-accelerated proton pulses. The experimental data is compared to synthetic dark-field values obtained from hydrodynamic simulations of a simplified foam model. Both experimental and simulation results demonstrate the viability of utilizing grating-based dark-field imaging for observing microstructural changes in foam targets.

The aim of this study was to evaluate the prospects of using natural fucosylated chondroitin sulfate (FCS) from the sea cucumber Cucumaria japonica as the active component of an implantable biodegradable scaffold to stimulate hematopoiesis in mice with cyclophosphamide (CPh)-induced myelosuppression. The scaffolds were based on bioresorbable Fe–Mn–C and Fe–Mn–Pd alloys after equal-channel angular pressing (ECAP). The efficiency of the developed constructs with FCS was compared with the activity of the same scaffolds loaded with recombinant human granulocyte colony stimulating factor, as well as solutions of these active compounds administered subcutaneously after the end of the cyclophosphamide (CPh) course. It was found that implantation of the Fe–Mn–C scaffold loaded with FCS most effectively stimulated hematopoiesis, providing a complex effect. This design of the developed constructs contributed to an increase in the concentration not only of leukocytes and neutrophils, but also platelets in the blood, promoted the proliferation of bone marrow cells, increasing the concentration of Ki-67(+) cells, and contributed to the restoration of the morphology of the animals’ spleen.

Abstract—The structure, composition, and specificity of accumulation of trace elements by rounded nodules in gleyic soddy brown-podzolic soils (Gleyic Luvisol (Manganiferric)) of nature reserves and a national park in the south of the Far East have been studied by advanced analytical methods and noninvasive techniques. The nodules are characterized by pronounced differentiation into external (brown and ocher-brown, Fe-enriched, and dense) and internal (dark brown, Mn-enriched, and loose) zones. According to the distribution of Mn compounds in the internal zone, two types of nodules are identified: with an undifferentiated internal zone and with a core (cores). The cores contain C-enriched microzones, which are centers of Fe and Mn precipitation. The stages of coprecipitation of Fe and Mn and the stages with predominant precipitation of one of the elements are identified in the nodules. The nodules consist of a complex of minerals inherited from soils, as well as of nodule-specific minerals (goethite, feroxyhyte, and birnessite). The Fe content in the nodules is, on average, four times higher than that in the soil, the Mn content is 21.9 times higher, and the C content is 3.6 times higher. The most intensive accumulation in nodules is typical for Pb (EF = 5.53–12.14), which is determined by the joint participation of C- and Mn-containing compounds in its binding. Nickel (EF 0.89–5.81) and Cr (EF 1.22–2.60) are less actively accumulated; and the accumulation of V (EF 0.85–1.88) and Sr (EF 0.58–1.43) is weak. The phases accumulating Ni, Cr, V, and Sr are represented by nodules containing Fe and C. Zinc does not accumulate in the nodules. A comparison of the concentrations of water-soluble forms of trace elements reflects a decrease in the mobility of Cr, Pb, Ni, V, and Sr in nodules as compared to soils.

using the modernized high-temperature installation, the elastic characteristics and internal friction of the fuel rod shells were investigated in hot cell in order to update computer codes for WWER-1000 fuel rods. The elastic characteristics of the shell are analytically described and obtained a numerical shape factor of the first longitudinal frequency is calculated. There is description of new measuring units that provide data gathering by automatic or half-automatic mode. The elastic modulus and internal friction temperature dependences are determined by application of high-temperature modernized device that provides carrying out experiments at a temperature of 1160 K. Obtained effect could be interpreted by the crushing of the structure of the material.

In this work, an advanced method is proposed for computational recovery of thermo-physical properties in a wide range from room temperature to values above the alloy melting point. This method allows us to improve material databases of CAE (Computer-Aided Engineering) programs for simulation of high-temperature technological processes. In most cases, computation of unsteady temperature fields is an important stage of CAE analysis in mechanical engineering. Moreover, various manufacturing technologies such as casting, welding, surface hardening, coating, heat treatment provide the desired material structure and its strength by controlling temperature field during solidification and subsequent cooling of a machine part. The problem of reliability in computer modeling arises from the fact that CAE programs usually are not equipped with comprehensive material databases. We have solved this problem especially for casting simulation and molding materials, which can differ in composition at different plants and therefore cannot be combined into a common database. To determine unknown thermo-physical properties, the temperature had been measured in several points of solidifying cylindrical sample initially, and the appropriate computer simulation of the test technology was performed. Then the difference between the calculated and experimental temperatures was minimized using the modified Levenberg-Marquardt optimization algorithm.

We study elastic characteristics and internal friction of fuel claddings to improve computer codes for VVER-1000 fuel rods. We analytically described elastic characteristics of cladding material and obtained coefficient of the form of the first longitudinal frequency numerically. We described new measuring module for automatic acquisition data. We’ve established temperature dependences of Young’s modulus and internal friction via high-temperature facility and developed electronic module and noted maximum of these characteristics at the temperature 1160 K. It can be explained by the destruction of the texture in the material of claddings.

This paper presents experimental data on the ignition induction period of synthetic hydrocarbons at various temperatures and pressures obtained using a shock tube. The experimental results were used to determine the influence of the ignition induction period on the combustion efficiency of hydrocarbons in high-enthalpy flows for diffusion-kinetic regimes An integral mathematical model is presented that takes into account the influence of the kinetic factors of ignition and combustion on the efficiency of physicochemical processes in air flow. The results of calculating the combustion efficiency of synthetic hydrocarbons in flows with different parameters are given.

Widespread use of Mg-Zn-Ca alloys in clinical orthopedic practice requires improvement of their mechanical properties—in particular, ductility—and enhancement of their bioactivity for accelerated osteoreconstruction. The alloy was studied in two structural states: after homogenization and after equal-channel angular pressing. Immersion and potentiodynamic polarization tests showed that the corrosion rate of the alloy was not increased by deformation. The mass loss in vivo was also statistically insignificant. Furthermore, it was found that deformation did not compromise the biocompatibility of the alloy and did not have any significant effect on cell adhesion and proliferation. However, an extract of the alloy promoted the alkaline phosphatase activity of human mesenchymal stromal cells, which indicates osteogenic stimulation of cells. The osteoinduction of the deformed alloy significantly exceeded that of the homogenized one. Based on the results of this work, it can be concluded that the alloy Mg-1%Zn-0.3%Ca modified by equal-channel angular pressing is a promising candidate for the manufacture of biodegradable orthopedic implants since it stimulates osteogenic differentiation and has greater ductility, which provides it with a competitive advantage in comparison with the homogenized state.

New data on the redistribution of impurities in beryllium of technical purity were obtained by Mössbauer spectroscopy. The metal with 0.15% aluminum, 0.11% iron and other impurities was investigated. The introduction of iron enriched with isotope 57Fe in addition to natural iron as an impurity provided the magnitude of the Mössbauer effect, sufficient for resolving the experimental spectra and determining the parameters of the supersaturated solution that decomposed and the secondary phases that appear. Isothermal annealing at 600 °C leads first to the precipitation of the AlFeBe4 phase, which predominates for 1,700 hours. During the solid-phase sequential reaction, the release of its final product of the FeBe11 type gradually develops. Modifications of the process, the necessary level of enrichment, as well as the possibility of regulating the distribution of impurities that affect the properties of beryllium are discussed. The results obtained can be useful in analyzing the behavior of impurities during heat treatment and operation of reactor beryllium and other materials.