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91.
ZHOUXiao-hua LEXue-yi LONGLa-sheng CHENShi 《高等学校化学研究》2005,21(1):119-122
It is important to research the mixed-ligand copper complexes containing bioligands, such as amino acids, nucleic acids and proteins, in exploring the functional mechanism of microelement copper in organism because the reaction of any micronutrient with two or more bioligands in the concentrated bioligands background gives mixed-ligand ternary complexes, which are more stable and related with storage of substance and transportationof metal ions in the life process. 相似文献
92.
Propylene polymerization on TiCl4/donor/MgCl2 (donor = ethyl benzoate, dibutyl phthalate, diisobutyl phthalate, diethyl 2,3-diisopropylsuccinate) supported catalysts is considered. The states of the donors in the catalysts have been investigated by diffuse reflectance IR spectroscopy. Data characterizing the distribution of the donors and the active component (TiCl4) on the support surface have been obtained. Molecular weight distribution data for polypropylene are presented. The molecular weight distribution of polypropylene depends on the location of the donor and TiCl4 molecules. 相似文献
93.
A. B. Mirgorodskaya F. G. Valeeva S. V. Zakharov D. A. Kuryashov N. Yu. Bashkirtseva L. Ya. Zakharova 《Russian Chemical Bulletin》2018,67(2):291-296
It was shown that the addition of organic electrolytes to aqueous solutions of morpholinium surfactants facilitates micellization, reduces the micellar surface potential, increases the hydrodynamic diameter of micelles and favors the formation of cylindrical micelles which behave as pseudoplastic fluids. At low shear rates, the viscosity is extremely large and changes insignificantly, and it decreases sharply with increase in shear rate. Significant decrease in viscosity upon the increase in shear deformations indicates the orientation of cylindrical micelles along the direction of the flow with the increase in shear rate. 相似文献
94.
Zh. A. Ezhova N. A. Zakharov E. M. Koval’ N. T. Kuznetsov 《Russian Journal of Inorganic Chemistry》2018,63(8):1001-1006
Nanocomposites (NCs) based on carbonated calcium hydroxyapatite (CHA) (bioapatite, an analogue of the inorganic component of mammalian bone tissue), carbonate apatite (Ca10(PO4)6CO3, CA), and multiwall carbon nanotubes (CNTs) are prepared in the system CaCl2–(NH4)2HPO4–NH4HCO3–NH3–CNT–H2O (25°C) by coprecipitation of calcium and phosphorus salts with CNTs from aqueous solutions. The physicochemical properties of nanocomposites are studied as dependent on their formation conditions and composition using the solubility (residual concentrations) method and pH measurements. The composition, crystal structure, morphology, spectroscopic and thermal characteristics of the synthesized CHA/CNT and CA/CNT NCs are determined using chemical analysis, X-ray powder diffraction, thermal analysis, and IR spectroscopy. Either CHA/CNT NCs of composition Ca10(PO4)6(CO3)x(OH)2–2х · yCNT · zH2O, where х = 0.2; 0.5; 0.8; y = 1, 2, 3; z = 6.8–10.8, or (when х = 1) CA/CNT NCs of composition Ca10(PO4)6CO3 · yCNT · zH2O, where y = 1–3; z = 6.9–10.8, are formed as the carbonate and CNT contents of the NC increase. Our results favor the understanding of the effect of carbonization and CNTs on the metabolic formation of native bone tissue apatite and can be used for the design of efficient ceramics for bone implants. 相似文献
95.
Isomerism, conformations, and molecular structure of a model molecule of vitamin K1 with a truncated side chain have been studied by the density functional theory calculations using B3LYP method and double-
and triple-ζ correlation consistent basis sets. The conformations of two possible (E and Z) isomers, formed by the rotations around three single C–C bonds closest to the naphthoquinone ring, have been studied. The
lowest energy conformers are stabilized by additional hydrogen bonds between hydrogen atoms of the side chain and an oxygen
atom in the naphthoquinone subunit. It is interesting to note that the structure of the energetically preferred conformer
of the E-isomer (3c) has been found to be similar to the solid state structures of phylloquinones in the photosystem I of cyanobacterium
Synechococcus elongatus. The excited electronic states of two lowest energy conformers have also been investigated. 相似文献
96.
97.
M. E. Prokhorov A. I. Zakharov O. Yu. Stekolshchikov M. S. Tuchin M. K. Abubekerov A. O. Zhukov 《Doklady Physics》2016,61(1):5-7
We propose to introduce a geometric control subsystem into the attitude control systems of space-craft that would allow the current system sensor configuration to be determined in real time. 相似文献
98.
99.
用熔融急冷法制备了系列不同Tm3+掺杂浓度的Ge30Ga5Se65玻璃样品,测试了样品折射率、拉曼光谱、吸收光谱以及800nm激光泵浦下的近红外及中红外波段荧光光谱和荧光寿命。用Judd-Ofelt理论计算了Tm3+在Ge30Ga5Se65玻璃中的强度参数Ωi(i=2,4,6)、自发辐射跃迁概率A、荧光分支比β和辐射寿命τrad等光谱参数。讨论了800nm激光泵浦下掺杂1Wt%Tm3+样品在近红外1.23,1.48和1.8μm处的发光特性及各量子效率,研究了800nm激光泵浦下的样品中红外荧光特性与掺杂浓度之间的关系,计算了常温下该基质玻璃中Tm3+:3H5→3F4跃迁对于3.8μm处的多声子弛豫速率Wmp和Ge30Ga5Se65玻璃基质中多声子弛豫常数W(0)和电子-声子结合常数α值。结果表明Ge30Ga5Se65硒基玻璃较低的声子能量可以大大降低稀土离子能级间跃迁的多声子弛豫概率,从而提高中红外荧光发光效率,因此硒基玻璃作为稀土离子的掺杂基质材料对实现中红外荧光输出是非常有利的。 相似文献
100.
A. N. Zakharov K. V. Oskomov S. V. Rabotkin A. A. Solov’ev N. S. Sochugov 《Technical Physics》2010,55(5):719-723
Gallium-doped zinc oxide films are deposited using an unbalanced magnetron sputtering system. The films are deposited by dc sputtering of a conducting ceramic target in an argon atmosphere. The substrate temperature is 150°C. The film surface morphology is studied by scanning electron microscopy and atomic force microscopy. As the degree of magnetron unbalance increases, the electrophysical properties of the films deposited along the system axis are shown to improve, and the distribution of the film electrical resistivity over the substrate surface becomes more uniform. 相似文献