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21.
The Mo-Ni-B alloys prepared by arc-melting are examined in as-cast and annealed states using x-ray diffraction, scanning electron microscopy with electron probe microanalysis, and differential thermal analysis. The temperatures of invariant equilibria are refined. The projections of liquidus and solidus surfaces are plotted for the Ni-rich region.  相似文献   
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The scientifically based selection of efficient chemical technologies is related to the integrated assessment of indicators of their energy and resource efficiency and environmental safety, as well as indicators of the quality of products. The authors conducted systematic analysis of the efficiency and competitiveness of two electrochemical technologies of chroming from the solutions based on chromium salts of different valences. The strengths and weaknesses of each technology have been defined using the methodology of SWOT analysis, and the defined qualitative indicators of the efficiency of technologies have been determined using the methods of nonparametric statistics.  相似文献   
24.
Subpicosecond transient absorption measurements were performed for several polymethine and squarylium dyes in ethanol solution and a polymeric host over the spectral range 400-1500 nm. A variety of nonlinear effects including saturable absorption, reverse saturable absorption, and gain were observed and analyzed. We observe strong excited-state absorption (ESA) in all dyes in the range 450-600 nm. We also report the first prediction and observation of additional ESA bands in the near-infrared range. The predictions were based on quantum chemical calculations and the ESA experiments were performed with femtosecond pump-continuum probe techniques. For polymethine dye 2-[2-[3-[(1,3-dihydro-3,3-dimethyl-1-phenyl-2H-indol-2-ylidene) ethylidene]-2-phenyl-1-cyclohexen-1-yl]ethenyl]-3,3-dimethyl-1-phenylindo lium perchorate, an additional ESA band was detected near 1250 nm, and for squarylium dye 1,3-Bis-[(1,3-dihydro-1-butyl-3,3-dimetyl-2H-benzo[e]indol-2-ylidene)meth yl]squ araine, two additional ESA bands were found around 870- and 1380-nm, respectively. To further study the nature of these transitions, the steady-state excitation anisotropy was also studied and compared with predictions. The relationship between ESA spectra of organic dyes and their molecular structure is discussed  相似文献   
25.
An experiment performed with the gyrotrons of the TJ-II ECRH system has been performed to influence the gyrotron output radiation with a relatively weak wave returned from an external mechanically modulated reflector. An original method is proposed for directly measuring the wavelength of electromagnetic radiation in the free space. The method has been demonstrated in measurements of the wavelength of a high-power gyrotron radiation in the millimeter wavelength range used for plasma ECR heating in the TJ-II stellarator.  相似文献   
26.
Translated from Poroshkovaya Metallurgiya, No. 4(328), pp. 76–80, April, 1990.  相似文献   
27.
In experiments in vitro on human blood, it was shown that nanodiamond (ND) particles change the kinetics of active oxygen generation (AOG), causing white cell destruction and erythrocyte hemolysis. Various mechanisms of the observed effects have been considered. Nanodiamonds adapted for biological research and possessing higher colloidal stability make it possible to obtain sterile hydrosols and mixtures with drugs and are more preferable for medical–biological research. We discussed the necessity of experiments in vivo and showed the first results of injection of the adapted nanodiamonds to the laboratory animals.  相似文献   
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Mollusks are unique animals with a relatively simple central nervous system (CNS) containing giant neurons with identified functions. With such simple CNS, mollusks yet display sufficiently complex behavior, thus ideal for various studies of behavioral processes, including long-term memory (LTM) formation. For our research, we use the formation of the fear avoidance reflex in the terrestrial mollusk Helix lucorum as a learning model. We have shown previously that LTM formation in Helix requires epigenetic modifications of histones leading to both activation and inactivation of the specific genes. It is known that microRNAs (miRNAs) negatively regulate the expression of genes; however, the role of miRNAs in behavioral regulation has been poorly investigated. Currently, there is no miRNAs sequencing data being published on Helix lucorum, which makes it impossible to investigate the role of miRNAs in the memory formation of this mollusk. In this study, we have performed sequencing and comparative bioinformatics analysis of the miRNAs from the CNS of Helix lucorum. We have identified 95 different microRNAs, including microRNAs belonging to the MIR-9, MIR-10, MIR-22, MIR-124, MIR-137, and MIR-153 families, known to be involved in various CNS processes of vertebrates and other species, particularly, in the fear behavior and LTM. We have shown that in the CNS of Helix lucorum MIR-10 family (26 miRNAs) is the most representative one, including Hlu-Mir-10-S5-5p and Hlu-Mir-10-S9-5p as top hits. Moreover, we have shown the involvement of the MIR-10 family in LTM formation in Helix. The expression of 17 representatives of MIR-10 differentially changes during different periods of LTM consolidation in the CNS of Helix. In addition, using comparative analysis of microRNA expression upon learning in normal snails and snails with deficient learning abilities with dysfunction of the serotonergic system, we identified a number of microRNAs from several families, including MIR-10, which expression changes only in normal animals. The obtained data can be used for further fundamental and applied behavioral research.  相似文献   
30.
Phosphatidylethanol (Peth) is formed in biological membranes when ethanol replaces water in the transphosphatidylation reaction catalyzed by phospholipase D. This charged lipid accumulates in the presence of ethanol, and it has unusual properties that can influence membrane structure and function. We have previously shown that dimyristoylphosphatidylethanol (DMPeth) and dipalmitoylphosphatidylethanol (DPPeth) form the interdigitated gel phase in the presence of Tris-HCl [O.P. Bondar, E.S. Rowe, Biophys. J., 71 (1996) 1440-1449]. In the present investigation, differential scanning calorimetry (DSC) and fluorescence have been used to investigate the effect of cholesterol on the phase behavior of DPPeth and DMPeth. Our results show that cholesterol prevents the formation of the interdigitated phase in the presence of Tris-HCl, and that ethanol counters this influence and restores the ability of these lipids to interdigitate. Pyrene-PC fluorescence probe was used in this investigation and gave results that were in agreement with the conclusions based on the DSC study.  相似文献   
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