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91.
92.
Kinetics and Catalysis - The structure and catalytic characteristics of a bimetallic catalyst containing Pd1In1 nanoparticles deposited on the surface of γ-Al2O3 were studied. The formation of...  相似文献   
93.
Journal of Experimental and Theoretical Physics - The silicon oxide thin films obtained by thermal SiO2 treatment in hydrogen electron cyclotron resonance plasma at various exposure times are...  相似文献   
94.
The new series of the LC ionomers containing copper ions has been obtained and their phase behavior has been studied. It was shown that at low metal ion concentrations in the LC ionomers (˜2 mol‐%) the induction of the SmA phase is observed. An increase in the copper ion concentration is accompanied by a slight rise in clearing and glass transition temperatures. The magnetic properties of LC ionomers were studied at the first time. It was shown that LC ionomers are antiferromagneties with a strong exchange interaction J = 174–178 cm–1. Temperature dependencies of the magnetic moment and the magnetic anisotropy are adequately described in the framework of the 1‐D‐Heisenberg linear‐chain model.  相似文献   
95.
A supported metal catalyst was designed, characterized, and tested for aqueous phase heterogeneous hydrogenation of vinyl acetate with parahydrogen to produce 13C‐hyperpolarized ethyl acetate for potential biomedical applications. The Rh/TiO2 catalyst with a metal loading of 23.2 wt % produced strongly hyperpolarized 13C‐enriched ethyl acetate‐1‐13C detected at 9.4 T. An approximately 14‐fold 13C signal enhancement was detected using circa 50 % parahydrogen gas without taking into account relaxation losses before and after polarization transfer by magnetic field cycling from nascent parahydrogen‐derived protons to 13C nuclei. This first observation of 13C PHIP‐hyperpolarized products over a supported metal catalyst in an aqueous medium opens up new possibilities for production of catalyst‐free aqueous solutions of nontoxic hyperpolarized contrast agents for a wide range of biomolecules amenable to the parahydrogen induced polarization by side arm hydrogenation (PHIP‐SAH) approach.  相似文献   
96.
Kinetics and Catalysis - Alumina-based cobalt-containing catalysts have been synthesized for the oxidation of organic dyes with hydrogen peroxide in the aqueous phase. According to X-ray...  相似文献   
97.
Kinetics and Catalysis - The LaMn1 – xFexO3 (х = 0–1) perovskites were prepared by the Pechini route and characterized by X-ray diffraction analysis, HR TEM, XPS, and BET. Their...  相似文献   
98.
The inertness of the cleaved (0001) surface of a Bi2Se3 single crystal to oxidation has been demonstrated using X-ray photoelectron spectroscopy, as well as atomic-force and scanning tunneling microscopy and spectroscopy. No intrinsic bismuth and selenium oxides are formed on the surface after a month of storage in air. Atomically flat surfaces with macroscopic sizes (∼1 cm2) and rms roughness less than 0.1 nm have been prepared, and (1 × 1)-(0001) Bi2Se3 atomic structure has been resolved. The tunneling conductance measurements have shown that the energy dependence of the surface density of states is quasilinear in the band gap of Bi2Se3.  相似文献   
99.
Hydrothermal conditions have been used in the preparation of a series of organic-inorganic hybrid materials of the cobalt-molybdophosphonate family. The reactions of MoO(3), cobalt(II) acetate or cobalt(II) acetylacetonate, tetra-2-pyridylpyrazine (tpyprz), and organodiphosphonic acids H(2)O(3)P(CH(2))nPO(3)H(2) (n = 1-5 and 9) of varying tether lengths yielded compounds of the general type {Co(2)(tpyprz)(H(2)O)(m)}4+/MoxOy{O(3)P(CH(2))(n)PO(3)}z. The recurring theme of the structural chemistry is the incorporation of {Mo(5)O(15)(O(3)PR)(2)}(4-) clusters as molecular building blocks observed in the structures of nine phases (compounds 2-9 and 11). The structural consequences of variations in reaction conditions are most apparent in the series with propylene diphosphonate, where four unique structures 4-7 are observed, including two distinct three-dimensional architectures for compounds 5 and 6 whose formulations differ only in the number of water molecules of crystallization. With pentyldiphosphonate, a second phase 10 is obtained which exhibits a unique cluster building block, the hexamolybdate [Mo(6)O(18){O(3)P(CH(2))(5)PO(3)}](4-). In the case of methylenediphosphonic acid, a third structural motif, the trinuclear {(Mo(3)O(8))(O(3)PCH(2)PO(3))}2- subunit, is observed in compound 1. The structural chemistry of compounds 1-11 of this study is quite distinct from that of the {Ni(2)(tpyprz)(H(2)O)(m)}(4+)/Mo(x)O(y){O(3)P(CH(2))(n)PO(3)}z family, as well as that of the copper-based family. The structural diversity of this general class of materials reflects the coordination preferences of the M(II) sites, the extent of aqua ligation to the M(II) sites, the participation of both phosphate oxygen atoms and molybdate oxo-groups in linking to the M(II) sites, and the variability in the number of attachment sites at the molybdophosphonate clusters. Since the charge densities at the peripheral oxygen atoms of the clusters are quite uniform, the attachment of {M(2)(tpyprz)}(4+) subunits to the molybdophosphonates appears to be largely determined by steric, coulombic, and packing factors, as shown by extensive density functional theory calculations.  相似文献   
100.
Kinetics and Catalysis - A multicomponent MoVSbNbCeOx/SiO2 oxide catalyst exhibiting high catalytic activity in the oxidative dehydrogenation of ethane to ethylene is synthesized by spray drying of...  相似文献   
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