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1.
Kirovskaya  I. A.  Filatova  T. N.  Nor  P. E. 《Semiconductors》2021,55(2):228-233
Semiconductors - According to developed methods, in the fields of the mutual solubility of initial binary compounds (InP, InSb, and CdS), solid solutions of the InP–CdS and InSb–CdS...  相似文献   
2.
Structures and compositions of the monomers guanidine acrylate and guanidine methacrylate, their homopolymers, and copolymers with diallyldimethylammonium chloride enriched in acrylate comonomer units were determined. It was shown that ampholytic copolymers, owing to their ionic nature, contained comonomeric guanidine acrylate or methacrylate units and diallyldimethylammonium chloride units, as well as the acrylate comonomer with the diallyl counterion and polymeric acrylate and diallyl ion pairs. It follows from IR and 1H NMR data that guanidine methacrylate has the same structure (with two hydrogen bonds) in the solid state and in solutions. Guanidine acrylate structures in the solid state and in dimethylsulfoxide are identical and analogous to guanidine methacrylate structure in this solvent. In water, the guanidine acrylate structure has another type of hydrogen bonding (with one hydrogen bond, where the proton is shifted toward the guanidine group). These features of hydrogen bonding of guanidine acrylate and guanidine methacrylate are also retained in their homopolymers and copolymers with diallyldimethylammonium chloride. It was shown that the thermal stability of the copolymers was higher than that of their homopolymers, confirming the formation of intramolecular ion pairs of oppositely charged units of ampholytic copolymers. Moreover, the thermal stability of guanidine methacrylate-diallyldimethylammonium chloride copolymers is higher than that of guanidine acrylate-diallyldimethylammonium chloride copolymers.  相似文献   
3.
Thermal Transformations of an Aluminoborophosphate Binder   总被引:1,自引:0,他引:1  
Thermal transformations of a commercial aluminoborophosphate binder are studied in a broad temperature range by optical microscopy, x-ray diffraction, IR spectroscopy, and thermal analysis. The introduction of B2O3 reduces the temperature of phosphate polycondensation, enhances the stability of cyclometaphosphates in a broad temperature range (180–1100°C), and reduces the stability of hydrogen phosphates.  相似文献   
4.
1.  The KhN65KVMYuTB alloy has properties that are sensitive to variations in the chemical composition within the limits of the turbine installations standard.
2.  The mechanical properties of the alloy with an upper level for the aluminum plus titanium content are 20% better than the corresponding properties for the alloy with a mean specification content for these alloys.
NPO TsNIITMASh, Elektrostal' Plant. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 7, pp. 29–31, July 1992.  相似文献   
5.
One of the requirements imposed on high-temperature nickel alloys for long-term operation under high temperatures and stresses is structural stability, which ensures constant properties during operation of parts. It is known that the main strengthening phase of nickel alloys is a -phase of the type (Ni, Cr)3(Al, N) or (Ni, Cr)3(Al, Ti, Nb), which may amount to 50% in deformable nickel alloys. In addition, these alloys contain a certain amount of carbides, borides, and carbonitrides (up to 3 wt. %). An increase in the content of alloying elements in high-temperature alloys may cause formation of undesirable TCP-phases in their structure. For example, at high contents of molybdenum and tungsten a thin lamellar p-phase (Ni, Co, Fe)7(Mo, W)6 is segregated. The authors investigated the effect of the -phase on the set of chemical properties of industrial alloy KhN60KVYuMB (pressed rods 105 mm in diameter).Translated from Metailovedenie i Termicheskaya Obrabotka Metallov, No. 9, pp. 15–19, September, 1995.  相似文献   
6.
The charge properties of a multilayer structure, composed of silicon-carbide polytypes on a silicon substrate, are investigated. Knowledge of the properties of the space-charge region of silicon and the possibility of affecting the surface of a structure by the field effect [1] provides data on the charge processes at the interfaces between the polytypes. These data are urgent for improving the methods of synthesizing electronic structures based on SiC polytypes.  相似文献   
7.
8.
The local development of atherosclerotic lesions may, at least partly, be associated with the specific cellular composition of atherosclerosis-prone regions. Previously, it was demonstrated that a small population of immature vascular smooth muscle cells (VSMCs) expressing both CD146 and neuron-glial antigen 2 is postnatally sustained in atherosclerosis-prone sites. We supposed that these cells may be involved in atherogenesis and can continuously respond to angiotensin II, which is an atherogenic factor. Using immunohistochemistry, flow cytometry, wound migration assay xCELLigence system, and calcium imaging, we studied the functional activities of immature VSMCs in vitro and in vivo. According to our data, these cells do not express nestin, CD105, and the leptin receptor. They are localized in atherosclerosis-prone regions, and their number increases with age, from 5.7% to 23%. Immature VSMCs do not migrate to low shear stress areas and atherosclerotic lesions. They also do not have any unique response to angiotensin II. Thus, despite the localization of immature VSMCs and the presence of the link between their number and age, our study did not support the hypothesis that immature VSMCs are directly involved in the formation of atherosclerotic lesions. Additional lineage tracing studies can clarify the fate of these cells during atherogenesis.  相似文献   
9.
The state of the surface of standard phosphorus-doped n-Si(111) and n-Si(100) (KEF grade) and boron-doped p-Si(111) (KDB grade) single-crystal wafers treated in a 50% HF–70% HNO3 (1: 3, v/v) polishing solution has been studied using soft X-ray reflection spectroscopy. The fine structure of the reflection spectra in the region of the Si L 2,3 ionization threshold has been analyzed. The dependence of the natural oxide thickness on the orientation of a silicon single crystal surface is established.  相似文献   
10.
Passivation of chrome-plated sheet iron in electrolytes based on Cr(III) salts and capable of completely replacing highly toxic and aggressive electrolyte based on Cr(VI), is studied.  相似文献   
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