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The spectra of absorption and gamma luminescence and integral thermoluminescence curves (300–605 K) of nominally pure LuAG crystals and praseodymium-doped LuAG:Pr crystals have been analyzed before and after irradiation with fast (>0.1 MeV) neutrons in the range of fluences of 1015–1017 cm–2. The optical spectra of LuAG:Pr, irradiated with neutrons with a fluence of 1017 cm–2, after thermal bleaching to 605 K and subsequent gamma irradiation and illumination in the induced band of 573 nm, indicate the electron transfer from the induced VO (Cimp) center to the hole Pr4+ center with radiation in Pr3+. In the case of high-dose (for the LHC supercollider (HL-LHC)) neutron irradiation at >300 K, localization of electrons on the induced F+ and VO (Cimp) defects and localization of holes on the activator Pr4+ centers decrease the intensity of high-speed (20 ns) activator luminescence and induces the occurrence of the long-term component in the recombination process. [ABSTRACT FROM AUTHOR]

Abstract: IR absorption spectra of quartz glass with varying contents of hydroxyl OH groups, namely, KU1 (1000 ppm OH) and KS-4V (≤0.1 ppm OH) are compared prior to and after exposure to fast neutron fluences of 1018-5 × 1019 cm-2. The appearance of the IR absorption band of 2260 cm-1 regardless of the large difference in the content of OH groups in nonirradiated KU1 and KS-4V glass is related to the bending vibrations of the bridging ≡Si−O−Si≡ bonds. A decrease in the amplitude of the band at 2260 cm-1 and shift of its maximum by 20 cm-1 to the IR range is caused by the decrease in the bridging ≡Si−O−Si≡ bond angle with the growth of the neutron fluence. The asymmetric band at 3674 cm-1, which is related to OH groups, is observed only in nonirradiated KU1 glass. An increase in the number of OH groups in KU1 glass and the formation of OH groups in KS-4V glass after the accumulation of the neutron fluence of ≥1019 cm-2 rationalizes the slow accumulation of the intrinsic defects such as nonbridging oxygen atoms and oxygen vacancies in both brands of the glass in the range of the neutron fluence. [ABSTRACT FROM AUTHOR]

In this thesis, the amount of carbohydrates in grape molasses is determined and information about the healing properties of grapes is presented. The medicinal properties of grapes have been known for a long time. Ripe and raw grapes were used as a medicinal plant in Eastern medicine. They also used grape juice, vinegar, and leaf stalks. Abu Rayhan Biruni said that the water that flows when cutting the stem of a grape has many healing properties. Essential oil is also extracted from its stem. The famous physician Abu Ali ibn Sina writes about the properties of grapes: "Grapes that have been stored for a while will nourish and strengthen the body." A well-ripened grape is less harmful than an unripe one. Grapes themselves are more useful than their juice. Grapes and raisins are good for intestinal pain. Raisins are also good for kidneys and bladder. Grape stem water, wild grape fruit juice eliminates blood spitting. It is also useful for diarrhea and colon diseases. The water of the grape stem crushes stones, cures gout, cysts, and temiratkini. The chemical composition of grape juice increases strength due to the presence of useful substances such as fructose, glucose, sucrose, raffinose, xylose. Those who havestones or sand in their kidneys will get rid of it if they constantly eat grapes and drinktheir juice. It is useful to drink grape juice against colds and asthma in the respiratorytract, it takes colds. Grape molasses has a dark reddish color, and the presence of carbohydrates in the chemical composition of grape molasses was determined by high-performance liquid chromatography. Fructose 3.25 mg, glucose 4.61 mg, sucrose 0.11 mg are found in grape molasses. was found to exist. Molasses is rich in carbohydrates, it is a medicinal product that gives energy, increases appetite, increases blood volume, and is used in anemia. Grape molasses contains 3.25mg of fructose, 4.61 mg of glucose, and 0.11 mg of sucrose. was found to exist. [ABSTRACT FROM AUTHOR]

Provides information on an experimental setup on small-angle neutron scattering (SANS) instrumentation using a two-detector system. Reason behind a considerable increase in the dynamic range of a SANS instrument; Factors affecting the scattering intensity of the vanadium standard of the two-detector system; Standard procedure for SANS experiments at the YuMO spectrometer.

Magnetic and structural properties of (Co) x(SiO2)1 − x nanocomposite systems have been investigated over a wide range of Co concentrations using small-angle neutron scattering in combination with magnetic, magneto-optic, and magneto-transport characterization. It was found that in the region of structural percolation [ABSTRACT FROM AUTHOR]

Herein, we investigated the influence of two types of nanoparticle fillers, i.e., amorphous SiO2 and crystalline ZrO2, on the structural properties of their nanocomposites with high-density polyethylene (HDPE). The composite films were prepared by melt-blending with a filler content that varied from 1% to 20% v/v. The composites were characterized by small- and wide-angle x-ray scattering (SAXS and WAXS), small-angle neutron scattering (SANS), Raman spectroscopy, differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). For both fillers, the nanoaggregates were evenly distributed in the polymer matrix and their initial state in the powders determined their surface roughness and fractal character. In the case of the nano-ZrO2 filler, the lamellar thickness and crystallinity degree remain unchanged over a broad range of filler concentrations. SANS and SEM investigation showed poor interfacial adhesion and the presence of voids in the interfacial region. Temperature-programmed SANS investigations showed that at elevated temperatures, these voids become filled due to the flipping motions of polymer chains. The effect was accompanied by a partial aggregation of the filler. For nano-SiO2 filler, the lamellar thickness and the degree of crystallinity increased with increasing the filler loading. SAXS measurements show that the ordering of the lamellae is disrupted even at a filler content of only a few percent. SEM images confirmed good interfacial adhesion and integrity of the SiO2/HDPE composite. This markedly different impact of both fillers on the composite structure is discussed in terms of nanoparticle surface properties and their affinity to the HDPE matrix. [ABSTRACT FROM AUTHOR]

• A new gemini surfactant with C18 unsaturated tails and bis(hydroxyethyl) ammonium head groups linked by butyl spacer was synthesized. • Without any additives the surfactant forms viscoelastic solutions with 1 kPa·s viscosity and 15 Pa elastic modulus. • Addition of 1 wt% n-decane induces the formation of microemulsion and drop of viscosity by 6 orders of magnitude. Gemini surfactants are promising to replace conventional monomeric surfactants in various applications. In this paper, a new gemini surfactant with long unsaturated oleyl tails and bis(hydroxyethyl) ammonium head groups linked by butyl spacer was synthesized. Its critical micelle concentration in salt-free water (12 µM) is much lower than for its monomeric analog (220 µM). Without any additives this surfactant can form viscoelastic solutions with the viscosity of up to 1 kPa·s and elastic modulus of 15 Pa at the conditions, when the viscosity of the single-chained monomeric analog is close to that of pure water. These are one of the highest values reported so far for C18-tailed gemini surfactants without additives. The structure of the gemini surfactant solutions was studied by cryo-TEM and SAXS. Cryo-TEM revealed the presence of closed-looped micelles coexisting with linear wormlike micelles as well as the regular spacing between the micelles arising from strong electrostatic repulsion between them. The SAXS curves were well-fitted by a form-factor of core–shell cylinder, which yielded the radius of the core and the thickness of the shell equal to 1.4 nm each. Addition of n-decane induced the drop of viscosity by 6 orders of magnitude accompanied by the transformation of wormlike micelles into microemulsion droplets with 4.4 nm radius. Such gemini surfactants providing high viscoelasticity to aqueous solution that is responsive to added hydrocarbon are promising for the application in oil recovery as thickeners of fracturing fluids that can be cleaned up without any breakers at the backflow of oil. [ABSTRACT FROM AUTHOR]

Neutron diffraction studies on the small-angle neutron spectrometer YuMO (Joint Institute for Nuclear Research, Dubna), based on the IBR-2 pulsed reactor, have been reviewed. The main parameters of small-angle spectrometers, based on the time-of-flight technique, are considered. It is shown that the flux on sample is the key parameter of the spectrometers based on pulsed sources, which makes it possible (along with application of a multidetector system) to expand the dynamic range of scattering vector magnitudes. The history of the setting up of the first small-angle instrument based on pulsed sources is overviewed. The directions of development of small-angle spectrometers are shown. The results of YuMO studies in the fields of polymers, biology, materials science, and physical chemistry are briefly reviewed. The main strategies of development of small-angle neutron scattering on pulsed sources are considered. The possibilities of the small-angle instruments based on a synchrotron source and on a neutron pulsed source are compared. [ABSTRACT FROM AUTHOR]

The size and volume fraction of fine particles of secondary β -phase formed during hardening heat treatment of pseudo-β-titanium alloy VT22 are determined using low-angle scattering of neutrons, x-ray diffractometry, electron back-scatter diffraction, and transmission microscopy combined with x-ray spectral microanalysis. Based on comprehensive use of experimental data obtained by methods of different restriction levels analysis is conducted for the size, shape, elemental composition, and volume content of fine particles obtained after different versions of hardening heat treatment. Activation of β -phase decomposition energy due to low-temperature aging is determined. [ABSTRACT FROM AUTHOR]

The absorption and thermoluminescence spectra and their relaxation in pure and praseodymium-doped LuAG crystals are comparatively studied to determine the contribution of intrinsic and impurity defects before and after irradiation by 60Co γ-quanta with an average energy of 1.25 MeV, dose rate of 0.8 Gy/s, and dose of 103 Gy at 310 K. The existence of intrinsic F+ defects with a typical absorption band at 375 nm and impurity Cr4+ centers absorbing at 285, 420, 490, and 595 nm in both LuAG and Pr:LuAG samples before irradiation is related to the crystal-growth technology and the impurity composition of the charge. An increase in the concentration of F+ and Cr4+ centers after γ-irradiation is caused by charging of neutral F centers and changing of the electronic state (valence) of Cr3+ impurity centers. Formation of antisite defect complexes LuAl3+-VO, which are responsible for a luminescence band at 335 nm, is suggested. The first broad peak at 340 K on the thermoluminescence curves of both samples after irradiation with a dose of 103 Gy is related to liberation of charge carriers from shallow trapping levels; thermal activation and radiative recombination with emitting centers begin at 310 K, which places the upper limit on the temperature range of application of these scintillation crystals. [ABSTRACT FROM AUTHOR]

An Erratum to this paper has been published: https://doi.org/10.1134/S1063774522070513 [ABSTRACT FROM AUTHOR]

The chromatin organization in chicken erythrocyte nuclei was studied by small-angle neutron scattering in the scattering-vector range from 1.5 × 10−1 to 10−4 Å−1 with the use of the contrast-variation technique. This scattering-vector range corresponds to linear dimensions from 4 nm to 6 μm and covers the whole hierarchy of chromatin structures, from the nucleosomal structure to the entire nucleus. The results of the present study allowed the following conclusions to be drawn: (1) both the chromatin-protein structure and the structure of the nucleic acid component in chicken erythrocyte nuclei have mass-fractal properties, (2) the structure of the protein component of chromatin exhibits a fractal behavior on scales extending over two orders of magnitude, from the nucleosomal size to the size of an entire nucleus, and (3) the structure of the nucleic acid component of chromatin in chicken erythrocyte nuclei is likewise of a fractal nature and has two levels of organization or two phases with the crossover point at about 300–400 nm. [ABSTRACT FROM AUTHOR]

A low-resolution ab initio shape determination was performed from small-angle neutron and X-ray scattering (SANS and SAXS) curves from solutions of polycarbosilane dendrimers with the three-functional and the four-functional branching centre of the fourth, fifth, sixth, seventh and eighth generations. In all cases, anisometric dendrimer shapes were obtained. The overall shapes of the dendrimers with the three- and four-functional branching centres were oblate ellipsoids of revolution and triaxial ellipsoids, respectively. The restored bead models revealed a pronounced heterogeneity within the dendrimer structure. The density deficit was observed in the central part and close to the periphery of the dendrimers. The fraction of the overall volume of the dendrimers available for solvent penetration was about 0.2–0.3. These results may help in the design of new practical applications of dendrimer macromolecules. [ABSTRACT FROM AUTHOR]

The software package for the YuMO spectrometer has been updated. The MS DOS programs used before the updating are compared to the similar new programs operating in the OS-9 environment. The merits and demerits of each program are discussed. The main features of the new software are described, and the results of the long-term operation of the new software package are analyzed. It is shown that upgrading the software has improved spectrometer control. [ABSTRACT FROM AUTHOR]