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161.
《Tetrahedron letters》1986,27(8):991-992
A simple and efficient method of preparing tetraaryl orthocarbonates from copper phenoxide and carbon disulfide is described. 相似文献
162.
《Journal of the Less Common Metals》1985,105(2):333-338
Hydrogen potential-temperature diagrams are presented for the V-H, Nb-H and Ta-H systems. The diagrams have been constructed from published thermodynamic data for the single-phase and two-phase regions in conjunction with the temperature-composition phase diagrams. 相似文献
163.
Cheng Jiaxin Yang Haitao Fan Chuanlin Li Rongxing Yu Xiaohua Li Hongtao 《Journal of Solid State Electrochemistry》2020,24(10):2199-2217
Journal of Solid State Electrochemistry - Fluidized bed electrodes (FBEs), which were discovered in the late 1960s, are 3D (three-dimensional) particle electrodes. The FBEs have been attracting... 相似文献
164.
为了研究光对生物柴油氧化安定性的影响,以小桐子生物柴油为研究对象,在20 ℃下用不同波长的光照射处理48 h,并对处理后的样品进行氧化安定性分析。 结果表明,不同波长的光对生物柴油氧化的促进作用是不同的,以紫光为代表的短波长光对小桐子油生物柴油氧化的促进作用最强,其诱导期由5.12 h降至2.65 h,减少48%;波长较长的红光对生物柴油氧化的促进作用最弱,其诱导期降至4.61 h,减少10%。 对不同波长的光处理的生物柴油进行酸值滴定、成分分析和紫外表征,结果表明,随着光波长的减小,生物柴油的酸值从0.2577 mg/g 增加到0.3438 mg/g;含有两个碳碳双键的亚油酸甲酯的相对含量降低;共轭双键的吸收峰增大。 说明光波长越短,对生物柴油氧化的促进作用越强。 相似文献
165.
JianXinCAO GuoFangLAI YiFengWANG YuanFengHUANG ShiDeLUO 《中国化学快报》2004,15(7):791-793
A new sesquiterpenoid was obstained from the leaves of Magnolia delavayi. Its structure was determined as 8β-acetoxy-10α-ethyloxy-guaia-4α, 11-diol on the basis of spectral evidence. 相似文献
166.
Under the assumption that the normalized mean curvature vector is parallel in the normal bundle, by using the generalized ChengYau's self-adjoint differential operator, here we obtain some rigidity results for compact submanifolds with constant scalar curvature and higher codimension in the space forms. 相似文献
167.
《Solid State Ionics》2006,177(5-6):569-572
Silicate sol–gel precursors of poly[bis(methoxyethoxyethoxy)phosphazene] and their corresponding hybrid networks were synthesized by hydrolysis and condensation reactions. Conversion of the precursor polymers to covalently interconnected hybrid networks with controlled morphologies and physical properties was achieved. Thermal analyses showed no melting transitions for the networks and low glass transition temperatures that ranged from approximately − 38 to − 67 °C. Solid solutions with lithium bis(trifluoromethanesulfonyl)amide in the network showed a maximum ionic conductivity value of 7.69 × 10− 5 S/cm, making these materials interesting candidates for dimensionally stable solid polymer electrolytes. 相似文献
168.
For the general fixed effects linear model:Y=X+, N(0,V),V0, we obtain the necessary and sufficient conditions forLY+a to be admissible for a linear estimable functionS in the class of all estimators under the loss function (d -S)D(d -S), whereD0 is known. For the general random effects linear model:
=XV
11
X+XV
12+V
21
X+V
220, we also get the necessary and sufficient conditions forLY+a to be admissible for a linear estimable functionS+Q in the class of all estimators under the loss function (d -S -Q)D(d -S -Q), whereD0 is known. 相似文献
169.
Fang He Hua Wang Yongnian Dai 《天然气化学杂志》2007,16(2):155-161
Chemical looping combustion (CLC) of carbonaceous compounds has been proposed, in the past decade, as an efficient method for CO2 capture without cost of extra energy penalties. The technique involves the use of a metal oxide as an oxygen carrier that transfers oxygen from combustion air to fuels. The combustion is carried out in a two-step process: in the fuel reactor, the fuel is oxidized by a metal oxide, and in the air reactor, the reduced metal is oxidized back to the original phase. The use of iron oxide as an oxygen carrier has been investigated in this article. Particles composed of 80 wt% Fe2O3, together with Al2O3 as binder, have been prepared by impregnation methods. X-ray diffraction (XRD) analysis reveals that Fe2O3 does not interact with the Al2O3 binder after multi-cycles. The reactivity of the oxygen carrier particles has been studied in twenty-cycle reduction-oxidation tests in a thermal gravimetrical analysis (TGA) reactor. The components in the outlet gas have been analyzed. It has been observed that about 85% of CH4 converted to CO2 and H2O during most of the reduction periods. The oxygen carrier has kept quite a high reactivity in the twenty-cycle reactions. In the first twenty reaction cycles, the reaction rates became slightly higher with the number of cyclic reactions increasing, which was confirmed by the scanning electron microscopy (SEM) test results. The SEM analysis revealed that the pore size inside the particle had been enlarged by the thermal stress during the reaction, which was favorable for diffusion of the gaseous reactants into the particles. The experimental results suggested that the Fe2O3/Al2O3 oxygen carrier was a promising candidate for a CLC system. 相似文献
170.
在相对论赝势从头算全有效空间多组态自洽场方法(CASSCF)基础上,对CdH分子进行了二级电子相关(SOCI)计算,得出此体系几个电子态的电子结构、势能曲线及光谱常数,认为,静态相关效应及动态相关效应对该体系的光谱性质等都有较大影响. 相似文献