Measurement of young's modulus and hardness of Al-50 wt % Sn alloy phases using nanoindentation

The nanoindentation method was used to measure the Young's modulus and hardness of the phases of the alloy Al-50 wt % Sn: α-aluminum and eutectic. Samples are obtained in different ways, i.e., traditionally via the transition of the melt into a homogeneous structural state by heating to a certain temperature, followed by cooling using the cooling rate greater by the order than that of the traditional method and via the addition of 0.06 wt % Ti and 1 wt % Zr to the binary alloy. It has been found that the most significant effect of the Al-50 wt % Sn phases on the Young's modulus is the transition of the melt into a homogeneous structural state and the introduction of Zr into the melt. As part of the mathematical theory of elasticity, a numerical evaluation of the interfacial pressure that arises due to the difference between Young's modulus of α aluminum and eutectic has been performed. The calculation has showed that the extra pressure is nine times less for the alloy formed through the transition of the melt into a homogeneous structural state than for the alloy produced via a traditional way. © 2013 Pleiades Publishing, Ltd

THE INFLUENCE OF PHYSICAL METHODS OF VEGETABLES PROCESSING ON THE QUALITY OF FROZEN PRODUCTS

The indicators of quality and microbiological safety of frozen vegetable semi-finished products (for example, cut beet) processed in a microwave field for subsequent storage for 18 months at a temperature of minus 20±2 °C. Treatment with a microwave field was carried out under the following conditions: power 600 W and duration 5 min (180 kJ); power 1000 W and duration 4 min (240 kJ). It is established that treatment in the microwave field contributes to the preservation of consumer qualities of the product (total solids content, mass fraction of soluble solids, bound moisture content, microbiological effect) in the process of long-term low-temperature storage.The indicators of quality and microbiological safety of frozen vegetable semi-finished products (for example, cut beet) processed in a microwave field for subsequent storage for 18 months at a temperature of minus 20±2 °C. Treatment with a microwave field was carried out under the following conditions: power 600 W and duration 5 min (180 kJ); power 1000 W and duration 4 min (240 kJ). It is established that treatment in the microwave field contributes to the preservation of consumer qualities of the product (total solids content, mass fraction of soluble solids, bound moisture content, microbiological effect) in the process of long-term low-temperature storage

The glucocorticoid hypothesis of depression: history and perspectives

An abnormality in adaptation to negative life events is considered as one of the main causes of the development of depressive symptoms. According to the corticosteroid receptor hypothesis of depression, stress-induced activation of the hypothalamicpituitary- adrenal (HPA) axis plays an important role in the induction of psycho-emotional disturbances. The end products of this axis, glucocorticoids, are involved in the formation of many physiological and behavioral responses to stress. Although the increase in hormone levels following a short-term intervention is directed towards rapid mobilization of the body’s efforts for overcoming potentially dangerous situation, a long-term exposure to stress or glucocorticoids may have negative consequences for mood or behavior. With respect to mechanisms of changing effects of glucocorticoids from protective to damaging, glucocorticoid receptors (GRs) received most attention. These receptors are widely expressed in the brain. They are important regulators of the transcriptional activities of numerous genes, including the gene for such a plasticity-related protein as the brain-derived neurotrophic factor (BDNF) which has been implicated in psychiatric disorders. In addition to direct effects on gene transcription, changes in expression of GR themselves resulting from stress and/or glucocorticoid effects, in turn can modify the functional responses to subsequent stimuli. The purpose of this review was to analyze available literature data on the effects of stress and glucocorticoids on the expression of GR in the hippocampus, which is traditionally considered as the most sensitive to stress brain structure. The review also addresses the implication of GR and BDNF interplay in the pathogenesis of stress-related disorders

ИССЛЕДОВАНИЕ ВЛИЯНИЯ СТРУКТУРНОГО СОСТОЯНИЯ РАСПЛАВА НА КРИСТАЛЛИЧЕСКОЕ СТРОЕНИЕ И МЕХАНИЧЕСКИЕ СВОЙСТВА ФАЗ СПЛАВА AL-50 МАС.%SN МЕТОДОМ НАНОИНДЕНТИРОВАНИЯ

Nanoindentation is used to measure Young's modulus, the hardness, the plasticity, and the yield strength of the phases in Al-50 wt % Sn alloy samples prepared by a traditional method and using liquid-state homogenization. The effect of an increase in the cooling rate by an order of magnitude and alloying with 0.06 wt % Ti or 1 wt % Zr on the mechanical properties of the phases in the Al-50 wt % Sn alloy is studied. The most substantial effect on Young's modulus of the phases in the Al-50 wt % Sn alloy is found to be exerted by the homogenization of the metallic liquid and the introduction of zirconium in the alloy melt: the metal forming of an ingot is improved substantially. © 2013 Pleiades Publishing, Ltd

Research on the possibility of extending the shelf life of cheese raw material and heat-treated cheese by their freezing for further use in HoReCa

The article presents the results of a study of the regularities of changes in the functional properties and quality indicators of heat-treated cheeses made from frozen cheese raw material or frozen after thermomechanical processing for further use in HoReCa. The objects of the study were: Caliatta cheese — a semi-hard ripening cheese intended as the main raw material in the production of heat-treated cheese, as well as heat-treated «pizzacheese», subjected to freezing at temperatures of minus 14 ±2 °Cand minus 55 ±2 °Cand low-temperature storage at a temperature of minus 14 ±2 °Cfor 270 days, followed by defrosting at a temperature of 20 ±2 °C. To confirm the possibility of using the freezing technique in order to increase the shelf life of both the original cheese raw material and heat-treated cheese, their microbiological and physicochemical indicators were determined by standardized methods. Studies of structural and mechanical (rheological) properties were carried out on a Weissenberg rheogoniometer, recording changes in the elastic modulus (G’) and dynamic viscosity (h’). The length of the cheese thread, as one of the main functional properties of the «pizza-cheese», was assessed with a fork test after baking. Organoleptic characteristics were assessed by flavor, texture and appearance. Research results have shown that low-temperature storage of frozen cheese can be considered as a way to retard biological and physicochemical changes, which is a safe way to increase shelf life. Freezing cheese raw material increases the length of the cheese thread in proportion to the temperature and duration of the low-temperature storage. When obtaining heat-treated cheese from both unfrozen and frozen cheese raw material, a significant deterioration in the desired functional properties is observed. Thus, the receipt of heat-treated cheese from the original cheese raw material for further use in the production of pizza is justified only by economic feasibility. Freezing «pizza-cheese» at a temperature of minus 55 ±2 °C, made from unfrozen cheese raw material, ensures the preservation of functional properties and increases the shelf life up to 150 days

Monoclinic form I of clopidogrel hydrogen sulfate from powder diffraction data

The asymmetric unit of the title compound, C16H17ClNO2S+·HSO4 −, (I) [systematic name: (+)-(S)-5-[(2-chloro­phen­yl)(meth­oxy­carbon­yl)meth­yl]-4,5,6,7-tetra­hydro­thieno[3,2-c]pyridin-5-ium hydrogen sulfate], contains two independent cations of clopidogrel and two independent hydrogensulfate anions. The two independent cations are of similar conformation; however, this differs from that observed in ortho­rhom­bic form (II) [Bousquet et al. (2003 ▶). US Patent No. 6 504 030]. The H—N—Cchiral—H fragment shows a trans conformation in both independent cations in (I) and a gauche conformation in (II). In (I), classical inter­molecular N—H⋯O and O—H⋯O hydrogen bonds link two independent cations and two independent anions into an isolated cluster, in which two cations inter­act with one anion only via N—H⋯O hydrogen bonds. Weak inter­molecular C—H⋯O hydrogen bonds further consolidate the crystal packing

QED radiative corrections to impact factors

We consider the radiative corrections to the impact factors of electron and photon. According to a generalized eikonal representation the e\bar e scattering amplitude at high energies and fixed momentum transfers is proportional to the electron form factor. But we show that this representation is violated due to the presence of non-planar diagrams. One loop correction to the photon impact factor for small virtualities of the exchanged photon is obtained using the known results for the cross section of the e\bar e production at photon-nuclei interactions.Comment: 8 pp, plain LaTe