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排序方式: 共有1024条查询结果,搜索用时 31 毫秒
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Kishibayev K. K. Tokpayev R. R. Atchabarova A. A. Efremov S. A. Voropaeva N. L. Fernández-Sanjurjo María José Nechipurenko S. V. Nauryzbayev M. K. Tassibekov Kh. S. Karpachev V. V. 《Russian Journal of Applied Chemistry》2016,89(10):1731-1731
Russian Journal of Applied Chemistry - 相似文献
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A novel Ni/Na – containing inorganic-organic hybrid supramolecule {(PW12O40)·[Na2(NiH2EDTA·H2O)(H4EDTA)·2H2O]·2H2O·H3O}n (short for NiEDTA-PW12) has been successfully synthesized by solution method, and investigated by thermogravimetric-differential thermal analysis (TG-DTA), ultraviolet visible (UV-Vis) spectroscopy, cyclic voltammetry (CV), photoluminescence (PL), ultraviolet visible diffuse reflectance spectrum (UV-vis DRS) and single-crystal X-ray diffraction (XRD). NiEDTA-PW12 exhibits intriguing infinite supramolecular structure with Na+ ions as linker. Furthermore, NiEDTA-PW12 displays a fast-responsive reversible photochromism under ultraviolet or visible light. The photochromic property of NiEDTA-PW12 has been investigated by techniques of UV-vis DRS and PL, and the impact of the O2 on fading of the colored NiEDTA-PW12 has been investigated. 相似文献
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We analyze the manipulability of competitive equilibrium allocation rules for the simplest many-to-many extension of Shapley and Shubik’s (Int J Game Theory 1:111–130, 1972) assignment game. First, we show that if an agent has a quota of one, then she does not have an incentive to manipulate any competitive equilibrium rule that gives her her most preferred competitive equilibrium payoff when she reports truthfully. In particular, this result extends to the one-to-many (respectively, many-to-one) models the Non-Manipulability Theorem of the buyers (respectively, sellers), proven by Demange (Strategyproofness in the assignment market game. École Polytechnique, Laboratoire d’Économetrie, Paris, 1982), Leonard (J Polit Econ 91:461–479, 1983), and Demange and Gale (Econometrica 55:873–888, 1985) for the assignment game. Second, we prove a “General Manipulability Theorem” that implies and generalizes two “folk theorems” for the assignment game, the Manipulability Theorem and the General Impossibility Theorem, never proven before. For the one-to-one case, this result provides a sort of converse of the Non-Manipulability Theorem. 相似文献
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The inhibition efficiency of 2-Pyrrolidin-1-yl-1,3-thiazole-5-carboxylic acid (PTCA) against mild steel (MS) corrosion was investigated in acidic solution by using quantum chemical calculations based on Density Functional Theory (DFT) method and electrochemical measurements. The electrochemical impedance spectroscopy (EIS), potentiodynamic, potential zero charge (pzc) analysis and electrochemical noise (EN) measurements at various concentrations (from 0.1 to 10 mM) and immersion times were utilized in experimental part. The surface analysis was achieved scanning electron microscope (SEM) and contact angle measurements in the absence and presence of 10 mM PTCA. According to DFT results, PTCA exhibited 3.737 eV band gap and 8.130 Debye dipole moment which were a signal of potentially convenient corrosion inhibitor properties. PTCA has a remarkable corrosion inhibition capability to mild steel, which inhibited both anodic and cathodic corrosion rates, relying on it's physically adsorption on the metal solution interface and protection ability was increased with increasing PTCA concentration. The obtained adsorption equilibrium constant was 11.11 × 103 M-1 and calculated standard free energy of adsorption was ?33.03 kJ mol?1. The determined activation energy values were 55.58 kJ mol?1 and 96.86 kJ mol?1 in 0.5 M HCl in the absence and presence of 10 mM PTCA, respectively. PTCA demonstrated a strong inhibition efficiency of 98.3%, after 168 h immersion, according to the EIS results. As a consequently, we recommend that PTCA is a convenient inhibitor in 0.1 M HCl for mild steel protection against corrosion. 相似文献
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温度效应是制约激光捷联系统惯性器件性能提高的重要因素。通过大量温度试验,结合陀螺和加速度计的温度误差特性分析,得到一种工程适用的温度模型;分别对各个惯性器件进行温度误差补偿,提高了系统精度。试验结果表明:该模型不仅改善了高低温状态下系统的性能,而且也适用于大变温率或大范围温度变化环境下的导航系统。温度补偿后,系统的导航定位精度平均提高了近40%。 相似文献
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波阻是飞行器超音速飞行的关键设计因素,精确捕捉激波在流场中的位置,是数值模拟含激波流场和精确计算波阻的一个重要研究内容.本文基于网格节点有限体积空间离散方法,采用AUSM格式与FVS格式的混合格式(MAUSM方法)计算对流通量,从而抑制在数值模拟流场出现的激波处振荡和过冲现象,确保AUSM准确捕获接触间断的特性和FVS格式捕捉激波的能力.本文使用MAUSM方法分别计算了在跨声速和超声速条件下的NACA0012翼型流场,并与中心差分格式的计算结果进行比较.结果表明,对于存在激波的翼型流场,MAUSM方法是有效的. 相似文献
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David Torréns-Martín Lucía Fernández-Carrasco María Teresa Blanco-Varela 《Journal of Thermal Analysis and Calorimetry》2013,114(2):799-807
Different binders of Portland cement, calcium aluminate cement and calcium sulphate (PC/CAC/C $ {\bar{\text{S}}} $ ) have been investigated to determinate the influence the CAC and C $ {\bar{\text{S}}} $ amount in the reactions mechanism. Several mixtures were studied, ratios of 100, 85/15 and 75/25 of PC/CAC with 0, 3 and 5 % of C $ {\bar{\text{S}}} $ . Conduction calorimetric technique was used to follow the hydration during 100 h. The XRD and FTIR techniques were used as support in the analysis of the hydration products. The results have shown that the studied ternary systems form an extra amount of ettringite, and changes in the reactions mechanism with respect to a PC. The reactions mechanism depends on the CAC and C $ {\bar{\text{S}}} $ amount present in the different binders. 相似文献