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51.
The optical, and electrophysical characteristics of hydrogenated silicon oxycarbonitride films synthesized by the plasma enhanced chemical vapor decomposition of the mixtures of 1,1,1,3,3,3-hexamethyldisilazane with oxygen and nitrogen in the temperature range of 373–973 K have been studied. It has been shown that the obtained films are highly transparent (transmittance is ~92–99%) in the UV, visible, and IR ranges of the spectrum; they have refractive indices in the range of 1.43–2.25, a low reflection coefficient of visible light (nearly 3%), and low dielectric permittivity.  相似文献   
52.
An efficient protocol for the direct sulfanylation of various 4‐hydroxycoumarins and 4‐hydroxyquinolinones in good yield with arylsulfonylhydrazides as sulfanylating agents was developed via copper(I) bromide⋅dimethyl sulfide‐catalyzed S–O, S–N bond cleavage and C–S cross‐coupling reactions. A highly selective fluorescence turning‐on sensing of cadmium(II) ions in water using the synthesized 3‐sulfanyl‐4‐hydroxycoumarin derivative was also investigated.

  相似文献   

53.
To establish principal regularities of the hydrotreatment of rapeseed oil fatty acid triglycerides (FATs), the kinetics of this process has been studied at temperatures of 300–380°C, contact times of 0.38–0.10 h, and a hydrogen pressure of 1.0 MPa in a flow fixed-bed reactor. The process is performed over nonsulfided nickel catalysts, which are of great practical interest for the production of green diesel. The kinetic scheme of the process with consideration for target products (alkanes) and all oxygen-containing by-products has been proposed. The quantitative estimate, which enables the prediction of the composition of products for other process conditions, has been obtained for the principal paths of the hydrotreatment of rapeseed oil FATs.  相似文献   
54.
A comparative study of propylene polymerization in liquid monomer is performed under laboratory conditions using the IK-8-21 Ti-Mg catalyst designed at the Boreskov Institute of Catalysis and imported industrial catalysts (conditionally labeled TMC-1, -2, and -3). The activity and stereospecificity of the catalysts are estimated along with properties of the resulting polypropylene (granular composition and physicomechanical characteristics). It is shown that the IK-8-21 catalyst is not inferior to imported counterparts in terms of catalytic properties in the synthesis of polypropylene. The polypropylene powder formed on IK-8-21 is homogeneous and has good morphology. The physicomechanical characteristics of polypropylene synthesized on the domestic IK-8-21 catalyst are similar to those for polypropylene prepared with the imported TMK-1 catalyst.  相似文献   
55.
Metals and Materials International - In the present work, Ni32-x-Ti-Ta18+x (x?=?0, 2, 3, 4, 5, 6, 7, 8) shape memory alloys, produced by arc-melting method. Then, differential scanning...  相似文献   
56.
Protection of Metals and Physical Chemistry of Surfaces - In the present work, a method for producing new shaped composite materials by introducing a metal-organic framework structure Cu-BTC110...  相似文献   
57.
Protection of Metals and Physical Chemistry of Surfaces - The atmospheric corrosion resistance of metals can be reached by the formation of ultrathin protective films on their surface. Over recent...  相似文献   
58.
Protection of Metals and Physical Chemistry of Surfaces - Protective properties of polymer coatings are mainly determined by their adhesion properties. Organosilanes represent the most commonly...  相似文献   
59.
Protection of Metals and Physical Chemistry of Surfaces - In this work, preparation of thermal barrier coatings based on zirconium oxide is shown. The phased treatment of the copper substrate is...  相似文献   
60.
Protection of Metals and Physical Chemistry of Surfaces - Kinetics of formation of phosphate coatings (PCs) on St3 carbon steel in zinc nitrate–phosphate solution (0.65 М Zn2+ + 0.3...  相似文献   
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