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991.
992.
993.
使用TPR和H2-TPD技术对镍铝系催化剂的还原和氢脱附性能进行了研究,并与其催化性能相关联。结果发现,镍铝系催化剂的氢脱附能力与其催化性能之间有一定联系,脱附氢能力越强,催化剂的甲烷部分氧化反应性能就越好,但催化性能与还原性能无直接关联。 相似文献
994.
Summary To match the need of high efficiency capillary column (plate number N2, Plate height H2 and carrier gas linear velocity U2), a new high efficiency packed column (N1, H1 and U1) at high carrier gas velocity with small capacity factor has been developed in the light of theoretical discussion of factors
effecting the column efficiency utilization ratio. 相似文献
995.
996.
[reaction: see text] Ring-opening metathesis polymerization (ROMP) of a photochromic 1, 2-bis(3-thienyl)cyclopentene monomer generated a series of novel polymers. All polymers exhibit reversible light-activated interconversion between their colorless-open and their colored-closed forms. 相似文献
997.
998.
Determination of impurities in highly pure platinum by inductively coupled plasma-atomic emission spectrometry 总被引:1,自引:0,他引:1
In this work, a cyclone spray chamber system is used in conjunction with an inductively coupled plasma-atomic emission spectrometer instead of the conventional Scott-type chamber system to reduce the lower limit of detection achieved by the instrument, and an internal standard element (Y) is introduced to eliminate the effects caused by the drift in the plasma background level. An ICP-AES method for the determination of 13 impurity elements in a highly pure platinum sample has been developed. In this method, it is not necessary either to add a platinum matrix to the calibration standard or to separate and concentrate the elements to be determined in the samples. The effect of the platinum matrix on the elements to be analyzed is corrected for by a background equivalent concentration subtraction method. The determination ranges of the method are as follows: 0.00010-0.0050% for Mg, Mn, Cu, Ag, Fe and Zn; 0.00030-0.015% for Au, Ir, Ni and Pb; 0.00050-0.025% for Rh and Al; and 0.00080-0.040% for Pd. The method is simple, rapid and accurate, and can be applied to the analysis of 99.9–99.995% pure platinum. 相似文献
999.
Jin Yan Dong Ye Gao Chen Hong Chuan Song Yan Ping He Lei Li Yong Ping Zhong Yan Hui Zhu Jie Cao Luo Wang Ke Qin Zhang Laboratory for Conservation Utilization of Bioresources Yunnan University Kunming China Department of Chemistry Yunnan Normal University Kunming China Provincial Key Lab of Rural Energy Engineering Yunnan Normal University Kunming China 《中国化学快报》2007,18(2):165-167
Microbial transformation of nigranoic acid by Caryospora carllicarpa YMF1.01026 afforded the new derivative 6β-hydro-xynigranoic acid. Its structure was elucidated by spectroscopic methods. 相似文献
1000.
Yanfeng Zhao Nengsheng Ye Rongli Zhang Xue Feng Guoan Luo Yiming Wang 《Frontiers of Chemistry in China》2007,2(4):422-427
High-resolution two-dimensional gel electrophoresis (2-DE), followed by computer-assisted image analysis was used to screen
protein patterns of normal and infarcted myocardial tissues for quantitative and qualitative differences in protein expression.
In the gels of pH 5–8 immobilized pH gradient (IPG) strips, 851 protein spots were detected in normal myocardial tissue and
1 032 protein spots were resolved in infarcted myocardial tissue. Thirteen protein spots only expressed in normal myocardial
tissue, and 14 protein spots only expressed in infarcted myocardial tissue. Results also showed that 49 protein spots displayed
quantitative changes in expression between normal and infarcted myocardial tissue. Eleven protein spots were subjected to
mass spectrometry (MS) analysis and seven proteins were identified by peptide mass fingerprinting (PMF). These proteins may
be involved in cardiovascular injury, and could play an important role in the treatment of coronary heart disease.
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Translated from Chemical Journal of Chinese Universities, 2006, 8(27): 1467–1471 [译自: 高等学校化学学报] 相似文献