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51.
Ammonia-treated activated carbon has been studied as a support of Ru-Ba catalyst for ammonia synthesis. It is shown that the
introduction of nitrogen leads to a decrease of ammonia synthesis activity for the catalysts with a low Ba/Ru molar ratio,
while no significant changes are obtained for the catalysts with a high Ba/Ru molar ratio, confirming that electronegative
impurities suppress the activity in ammonia synthesis and consume part of the promoters.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
52.
XI Jingyu QIU Xinping ZHU Wentao & CHEN Liquan Department of Chemistry Tsinghua University Beijing China 《中国科学B辑(英文版)》2005,48(6)
All solid-state lithium polymer batteries may be one of the best choices for the future electrochemical power source, characterized by high energy densities, good cyclability, reliability and safety[1,2]. Owing to its potential capability to replace the t… 相似文献
53.
Y. H. Wen S. Lahiri Z. Qin X. L. Wu W. S. Liu 《Journal of Radioanalytical and Nuclear Chemistry》2002,253(2):263-265
An attempt has been made to develop a radiochemical methodology for the decontamination of a trace amount of radioactive cesium from a bulk amount of natural NaCl by liquid-liquid extraction (LLX). Open chain crown ethers, of amide type, namely, N,N,N",N"-tetraphenyl-3,6-dioxaoctanediamide (TDD), N,N,N",N"-tetraphenyl-3,6,9-trioxaundecanediamide and N,N"-dinaphthyl-N,N"-diphenyl-3,6-dioxaoctanediamide (DDD) have been chosen for this purpose. The separation factor between Cs and Na is the highest when 10-4M TDD dissolved in nitrobenzene is used as extractant and 0.4M picric acid at pH 5.0 is used as aqueous phase. About 60% Cs is extracted in this condition in a single run. 相似文献
54.
This review aims to provide a summary of the progress in TP small molecule fluorescent probes for enzymes in recent years and displays the main fluorescent mechanisms that have been applied to design probes. 相似文献
55.
用火焰原子吸收法测定了2000例甲亢病人的血清镁含量及1200例天津市正常人群血清镁含量,结果显示,甲亢病人血清镁含量显著低于正常人群,有显著统计意义(P〈0.01)。提示:甲亢病人血清镁含量对甲亢病诊断及治疗过程的镁的摄入补充有重要的意义。 相似文献
56.
Gejihu De Weiping Qin Jisen Zhang Yan Wang Chunyan Cao Yang Cui 《Journal of solid state chemistry》2006,179(3):955-958
In this work, we used the hydrothermal method to synthesize Eu3+ ion-doped cubic BaF2 nanorods, which is a luminescent material. The clubbed structures were well crystallized and exhibited face-centred cubic structures, as indicated by powder X-ray diffraction, scanning electron microscopy, electron diffraction, and transmission electron microscopy. The luminescent properties were studied, and local symmetry surrounding Eu3+ ions and electronic transition processes included. The results indicated that Eu3+ occupied only one C4ν site in nanorods. 相似文献
57.
Xin Sheng Li Yao Jun Zhang Qin Xin Chun Xin Ji Yan Fen Miao Li Wang 《Reaction Kinetics and Catalysis Letters》1996,57(1):177-182
Volumetric H2-uptake measurements on an Mo2N (79 m2g–1) sample reduced at 673 K have been carried out and the uptake isotherms in the temperature range of 308–623 K have been determined. Both the total and reversible hydrogen uptake increased with the uptake temperature. The irreversible hydrogen uptake increased abruptly when the uptake temperature was raised up to 423 K. The maximum of irreversible hydrogen uptake was measured at 473 K. The HIR/Mo ratio calculated from the uptakes obtained in the temperature range of 308–623 K varies in the range of 0.0010–0.0202. One possible mechanism for hydrogen adsorption is proposed to be heterolytic dissociation on Mo-N paris, in which the molybdenum atoms are in unsaturated coordination. 相似文献
58.
模式识别—人工神经网络在化学中的若干新应用 总被引:2,自引:0,他引:2
本文通过我们应用模式识别-人工神经网络方法预报新化合物、熔盐相图以及复杂化学反应体系的研究,展示应用模式识别-人工神经网络方法与物理化学理论相结合,研究化学现象的可能性和应用价值。 相似文献
59.
活性酚醛树脂中羟甲基含量的测定 总被引:12,自引:0,他引:12
本文提出一种酚醛树脂中羟甲基含量的化学分析法,分别以^13CNMR和化学分析法测定酚醛树脂的羟甲基含量。将两种测试结果与已知的投料量进行比较,证明所建立的化学分析法可行。 相似文献
60.
A novel sensitive method for the determination of nucleic acid (DNA) using the resonance light scattering (RLS) spectra of pentamethoxyl red has been developed. It is based on the effects on the resonance light scattering of Pentamethoxyl Red. The effective factors and the optimum conditions were studied, and the enhanced intensity of RLS is in proportion to the concentration of nucleic acids in the range of 0–2.54 µg mL−1 for ct-DNA, 0–4.54 µg mL−1 for hs-DNA. The limits of detection are 1.1 and 2.1 ng mL−1, respectively. Most foreign substances do not interfere in the determination, and the method has good selectivity and high sensitivity. It has been applied to the determination of DNA in synthetic samples and in real samples with satisfactory results. 相似文献