880 resultados para Mark 1:29-39
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合成了x值不同的La2 -xSrxCuO4±λ( 0 .0≤x≤ 0 .1 )和La2 -xThxCuO4±λ( 0 .0≤x≤ 0 .4)两系列K2 NiF4型复合氧化物催化剂 ,用XRD和IR研究了催化剂的晶体结构 .利用化学分析和XPS等方法测定了该系列含Cu氧化物中Cu离子的平均价态、非化学计量氧 (λ)和催化剂的表面和体相组成 .通过控制B位Cu离子的价态和氧化物的非化学计量氧在一定范围内有规律的变化 ,考察对NO +CO反应的催化性能 ;利用MS TPD法研究了该系列氧化物对NO和CO +NO等小分子的吸附和活化性能 ,在此基础上探讨了含Cu的A2 BO4型复合氧化物对NO +CO反应中的催化作用本质 .发现在低温反应条件下 ,NO分子的活化是控制步骤 ,催化剂的活性与低价离子及其含量有关 .在较高反应温度下 ,NO的吸附为控制步骤 ,催化活性与氧空位有关
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Charge transport in polypyrrole doped with indigo-carmine was investigated by the method of electrochemical alternating current impedance. By the nonlinear least square fitting, the equivalent circuit and parameter of each component are obtained. The apparent diffusion coefficients and heterogeneous electron transfer constants are given. It is found that, along with the increasing of film thickness, D-app and k(0) increase also.
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利用交流阻抗法研究了靛红掺杂聚吡咯膜内的电荷传输问题,通过非线性最小二乘法拟合,得出了体系的等效电路,并计算出其电行扩散系数和异相电子传递反应速率常数.实验结果表明,随着膜厚的增加,活性点增多,异相电子传递反应速率常数增大,同时表观扩散系数也增大.
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[(C6H5CH2C5H4)(2)GdCl . THF](2) (1) and (C6H5CH2C5H4)(2)ErCl . THF (2) were prepared by the reaction of LnCl(3) (Ln=Gd, Er) with benzylcyclopentadienyl sodium in THF and characterized by elemental analysis, IR, H-1 NMR, C-13 NMR, MS and thermal gravimetry. The crystal structures of both compounds were determined. Complex 1 is dimeric and its structure belongs to the monoclinic, P2(1)/c space group with a=1.1432(2), b=1.2978(2), c=1.7604(3) nm, beta=108.75(2), V=2.4732(9) nm(3), Z=2(four monomers), D-c=1.54 g . cm(-3). R=0.0342 and R(w)=0.0362. Complex 2 is monomer and its structure belongs to the orthorhombic, P2(1)2(1)2(1) space group with a=0.8645(2), b=1.1394(3), c=2.5289(4) nm, V=2.4919(9) nm(3), Z=4, D-c=1.56 g . cm(-3). R=0.0514, R(w)=0.0529. The determination of the crystal structure shows that in complex 1 the benzyl groups on the cyclopentadienyls coordinated to Gd3+ are located in the opposite direction (139 degrees); in complex 2 the benzyl groups on the cyclopentadienyls coordinated to Er3+ are located in the same direction (6.5 degrees).
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简述了近年来有关二烷基膦酸萃取稀土及相关金属离子的研究动向,展示了我们实验室在这方面的部分研究结果。
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A modified method for dispersing platinum particles on a glassy carbon (GC) electrode was investigated. The ultramicro Pt particle-modified electrode obtained exhibited high catalytic stability and activity towards the oxidation of some halide ions (Br-, I-) and inorganic sulfur species (S2O32-, SO32- and SCN-). These anions were separated and detected by using ion chromatography and electrochemical detection via this novel dispersed Pt particles-GC working electrode. The detection limits were 20 ng/ml for Br-, 1.0 ng/ml for I-, 10 ng/ml for SO32- and 4.0 ng/ml for SCN-. This method was employed for the analysis of industrial and environmental waste waters.
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以玻璃毛细管为样品池建立了测定痕量铁的光热折射光谱实验装置,选用狭缝取代针孔和采用探测束聚焦的检测方式,获得了较好的信噪比。测定铁一邻菲啉的检测下限为4.0×10-8mol/L,相当于4.0×10-6吸光度,并与其他光热测量结果相比,讨论了提高灵敏度的可能途径。
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Water vapor absorption and desorption by poly (phenylene oxide) (PPO) and sulfonated PPO (SPPO) membranes were studied at a constant temperature of 30-degrees-C and over a broad range of water activity (0.05 less-than-or-equal-to a < 0.8) by the weighing
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Electrocatalytic oxidation of sulfhydryl compounds was effective on a copper hexacyanoferrate (CuHCF) film glassy carbon electrode, at a significantly reduced overpotential (0.55 to 0.65 V) and for a broader pH range (2.0 to 7.0). The electrocatalysis was
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本文广泛地总结了熔融碳酸盐燃料电池在世界范围内所取得的进展;阐明了电池的工作原理和电池结构上最新发展,最终强调了进一步研究的一些问题