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81.
A cluster complex Cs3Nb2I9 is obtained by a high-temperature reaction of niobium, iodine, and cesium iodide. Its crystal structure is determined: trigonal space group P63/mmc, a = 8.2463(3) Å, c = 19.5419(14) Å, V = 1150.84(10) Å3, R(F) = 0.0614. The compound obtained is characterized by temperature independent paramagnetism in the temperature range 70–290 K.  相似文献   
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Il’ves  V. G.  Sokovnin  S. Yu.  Zuev  M. G.  Uimin  M. A.  Rähn  M.  Kozlova  J.  Sammelselg  V. 《Physics of the Solid State》2019,61(11):2200-2217
Physics of the Solid State - Mesoporous nanocrystalline CaF2 powder was produced by pulsed electron beam evaporation (PEBE) in vacuum. The specific surface area (SSA) of CaF2 nanopowder (NP)...  相似文献   
85.
Problems of dyeing of para-aramid fabrics with preservation of their performance characteristics: incombustibility, high strength, and durability are considered. Evidence for the efficiency of domestic polyurethane polymers for durable dyeing of aramid fabrics by inorganic black pigment is obtained. The technologies for resist and deep dyeing of fire-resistant fabrics are demanded by manufacturers and are competitive.  相似文献   
86.
Structural features of localization of chiral isomers of 1‐phenylethanol (R‐PhEtOH and S‐PhEtOH) and their mobility activation in homochiral metal‐organic [Zn2(bdc)(S‐lac)(dmf)] sorbent were studied with 1H and 13C NMR methods. 13C NMR chemical shifts do not show obvious advantage of selective interaction of molecule guests. But activation molecular mobility of S‐PhEtOH and R‐PhEtOH clearly indicates that stabilization of [Zn2(bdc)(S‐lac)(dmf)]·S‐PhEtOH structure is more preferable than stabilization of [Zn2(bdc)(S‐lac)(dmf)]·R‐PhEtOH structure. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
87.
The results of studying thin fluorocarbon films deposited onto single-crystal silicon plates through electron beam polymerization of hexafluoropropylene from the vapor phase are presented. The films are deposited under the action of an electron beam with an energy of 40 keV at a monomer vapor pressure of 5- 20 hPa. It is shown that plastic solid films consisting of a low-molecular-mass polymer with low thermal stability are formed at a beam current density on the order of 20 μA/cm2, while at current densities on the order of 150 μA/cm2, rigid brittle films of three-dimensional crossl inked polymer are formed with a thermal stability of about 350°C. It is assumed that the films are formed via chain polymerization, which at high current densities, is accompanied by polyrecombination processes leading to efficient chain crosslinking. It is found that polymer clusters are ordered in the course of film formation.  相似文献   
88.
Ozone decomposition with commercial and prototype filtering microfibrous material based on some polymers, fiberglass, and polymer-carbonized fibers was studied. Ozone treatment leads to degradation of polystyrene, polyvinyl chloride, cellulose acetate, and carbon fibers; polyacrylonitrile fibers are stable under the experimental conditions.  相似文献   
89.
It is shown that the abnormal long-range Te-Te intermolecular interaction in TeO(2) crystals may be related to the tunneling of electrons from the 5s(2) active lone pairs of Te(4+) ions and their partial delocalization on neighboring Te(4+).  相似文献   
90.
The results of many-year studies of the relationship between the physical properties and photocatalytic activity of TiO2 and Pt/TiO2 in photocatalytic purification and disinfection of air and water and water photodecomposition with oxygen evolution are presented. Recommendations are given as to finding the optimal method for platinum supporting on TiO2 to achieve the highest possible catalytic activity. Multisite kinetic models of the gas-phase oxidation of simple organic substances are considered. Methods for regenerating the photocatalyst after its deactivation in the oxidation of sulfur-containing organic substances are suggested. New data are discussed on the acceleration of air purification by the combination of photocatalytic oxidation with atmospheric electric discharges, the addition of gaseous hydrogen peroxide, and oxidation on photocatalysts existing in the aerosol state. As compared to pure TiO2, platinated titanium dioxide has a higher capability for disinfection and complete mineralization of microorganisms. Two promising methods for production of hydrogen from water using solar light are presented.  相似文献   
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