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111.
Gang XU Cheng Cai AN Jun FENG Yun Xiang CI Jin Hua TIAN Zhang Liang CHENI 《中国化学快报》2000,11(7):597-600
IthasbeenreportedthatTrichosanthi11(TCS),isolatedfromrkiI-ilolt)ii,hasanti-tumorI-4andanti-vira1activities5-'.Someanti-tun1orremedies,whicharedesignedfromTCS,arebeingtestedanddeveloped'-.'.StudyingthebioIogicalphenomenonbyelectrochemicalmethodsisanewhotresearchspotemerginginrecentyears".Manyresultsshowedthatnotonlytheenzymesystemsuchassuccinatedehydrogenasedisplayedthediode-likebehaviorduringtheelectrontransferprocess",butalsothehigh1yorganizedorganeIle,forexample,mitochondria,andevenintac… 相似文献
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LaPO4纳米微粒的制备及表征 总被引:5,自引:0,他引:5
Surface-modified LaPO4 nanoparticales were synthesized in the mixture solvent of water-ethanol with the surface modification age of dialkylphosphate. The conditions of synthesis and characterization were discussed. The results indicated that nanoparticle core of LaPO4 and surface-modified layer were formed. The surface-modified nanoparticles of LaPO4 can be dispersed in organic solvent and has better lubricating properties. 相似文献
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建立了筛落式粉尘火焰试验装置和火焰信的号光电测量系统。提出确定火焰前沿位置的“最大斜率切线法”和判定火焰传播稳定性的“相对入射能量法”。测定了硅钙粉和煤粉的火焰传播速度和火焰厚度。结果表明数据合理,测量装置和方法可用于速度范围很宽的粉尘火焰传播研究,用修正的田中达夫模型计算的硅钙粉层流火焰传播速度与实验值接近。 相似文献
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An efficient, amine- and phosphine-free palladium(II)-catalyzed homocoupling of terminal alkynes has been developed. In the presence of PdCl2, CuI, Me3NO, and NaOAc, homocoupling of various terminal alkynes underwent smoothly to afford the corresponding diynes in moderate to high yields without any phosphine ligands. In contrast, the presence of a phosphine ligand (PPh3) disfavored this palladium-catalyzed homocoupling procedure. Bases, solvents, and CuI have fundamental influence on the palladium-catalyzed homocoupling of terminal alkynes. 相似文献
119.
Three new hetero‐bischelated rhodium (III) complexes of cis‐[Rh(PA)(L)Cl2]Cl (where PA = phenylpyridin‐2‐ylmethylene‐amine; L = 2,2′‐bipyridine, 2,2′‐dipyridylamine and 1,10‐phenanthroline) have been successfully prepared and characterized. Each complex shows high intensity bands in the UV region, and these are assigned to spin‐allowed π‐π* transitions. The medium‐intensity absorption band profile in the lower energy region can be explained by convolution of spin‐allowed CT and d‐d* transitions. The emission spectra at low temperature (77 K) of these complexes in EtOH/MeOH (4:1 v/v) are virtually identical. They all exhibit a broad, symmetric, and structureless red emission with a microsecond lifetime and hence are assigned as the d‐d* phosphorescence. 相似文献
120.
In this study, local least squares (LLS) and principal component analysis (PCA) were applied to deal with the disturbances in a data set of chromatographic fingerprints after necessary data transformations. It has been demonstrated that PCA with standard normal variate (SNV) transformation of data led to meaningful classification of 33 different Erigeron breviscapus herbal samples. The result was also corroborated by variance squares discriminant method. The quality of herbal objects was further evaluated, and the causes of this fact have been explained from a chemical point of view. At the same time, it implied an idea for qualitative evaluation of the herbal objects with a common class pattern of chromatographic fingerprints. 相似文献