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41.
Technologies of preparation for gluing of surfaces from aluminum, beryllium alloys, porous materials (glass-fiber plastics and heat-protective materials), and technologies of polyimide film, rubber, and fabric gluing are described. It is shown that the application of epoxy primer, phosphatizing (mordant) coat, VK-32-200 and VK-25 phenolic-elastomer adhesives, and adhesive sublayers and primers allows one to preserve the activity of the preliminary treated adherent surface. The modification of polypropylene and polyester fiber surfaces by the coupling agents based on silanes with the aim to improve the nonwoven fabric properties is considered.  相似文献   
42.
Russian Journal of Applied Chemistry - The process of Pd(II) sorption from hydrochloric acid solutions was studied in the pH range of 0.5–5.0 in the presence of Pt(IV) and a number of...  相似文献   
43.
Russian Journal of Electrochemistry - The possibility of synthesizing oxygen-ion conductors based on bismuth molybdate with antimony and tin substituted to the molybdenum sublattice is studied and...  相似文献   
44.
Doklady Chemistry - The boundaries of Mg1 – xNixGa2O4 solid solutions (0 ≤ х ≤ 0.5) with a spinel structure synthesized by the gel combustion method,...  相似文献   
45.
Experiments on extraction of gold(III) from hydrochloric acid solutions with isomeric aliphatic alcohols containing 6–12 carbon atoms showed that secondary alcohols recover AuCl4? from acid solutions with higher distribution ratios than primary alcohols do. The best alcohol that can be recommended for the extraction of gold(III) from 3–6 M HCl solutions, taking into account the solubility and extraction ability of alcohols, is 2-octanol. The possibility of efficient stripping of gold(III) from the 2-octanol phase with ammonia or thiourea solutions was demonstrated.  相似文献   
46.
A study of the mechanism by which bismuth is electrodissolved in an aqueous solution of thiourea on the background of H2SO4 demonstrated that, in the thiourea concentration range 0.001 M < c < 0.5 M, a current oscillation is observed in cyclic voltammograms at E ≈ 0.4–0.3 V when the potential is swept from the anodic to the cathodic region. This oscillation is due to the loosening of the passivating film formed in the anodic process. It is shown that thiourea is not oxidized to formamidine disulphide at the bismuth electrode. thiourea and formamidine disulphide have mutually opposite effects on the height of the cathodic peak: the peak current falls with increasing thiourea concentration and grows with increasing formamidine disulphide concentration. According to the results of an X-ray fl uorescence analysis, sulfur is formed on the bismuth electrode upon its prolonged polarization of in a 0.5 M solution of thiourea. An explanation is provided for the experimental facts observed in the study.  相似文献   
47.
Russian Chemical Bulletin - Phase equilibria in the mixtures of polyvinyl alcohol (PVA) and chitosan were revealed. Structures of the phases were identified. The temperature and concentration...  相似文献   
48.
Russian Journal of Organic Chemistry - Michael adduct of levoglucosenone and cyclohexanone, 1,6-anhydro-3,4-dideoxy-4-C-(2-oxocyclohexan-1-yl)-β-D-erythrohexo-2-ulose, was treated with...  相似文献   
49.
Russian Journal of Organic Chemistry - Alkylation of 5-allyl-6-methyl-2-thiouracil with benzyl chloride and allyl bromide afforded 2-benzyl(allyl)sulfanyl-5-allyl-6-methylpyrimidin-4(3H)-ones....  相似文献   
50.
Russian Journal of Organic Chemistry - Mannich reaction of N-propargyl triterpene aldimines obtained from betulonic and oleanonic aldehydes gave new aminoalkyl derivatives containing an...  相似文献   
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