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11.
设 G=(A,△)为紧矩阵量子群,G为A的所有有限维光滑的、不可约余表示等价类的集合.本文通过(A,△)的一个余表示Vo构造了两个相互配对的集合,利用Hilbert C*-模的理论证明它们分别为A和Baaj与Skandalis构造的量子群A,并且证明了对任意的α∈G,在A中都对应一个有限维投影算子Pα,满足 dim(α)=dim(pα). 相似文献
12.
The study of bed-load transport is of great significance both in theory and in practice. This paper discusses the saltation
of bed-load solid grains in flowing water. Experiments and theoretic analysis have been made by means of high-speed photographing
and advanced data processing technique with a combined method based on mechanical and statistical theories. It indicates that
the saltation is the main form of the bed-load transport under ordinary flowing conditions. In the meantime, taking successive
saltation as the model of bed-load transport, systematic analysis has been made with regard to the kinematic properties and
mechanism of saltation. The statistical analysis shows that the probability density functions of the relative height and length
of saltation are in conformity with Γ-type distribution, while the probability density functions of the relative velocities
of saltation are in conformity with the Gaussian distribution.
The project supported by National Natural Science Foundation of China 相似文献
13.
Xia Yin Weiguang Zhang Qijiao Zhang Jun Fan Chian Sing Lai Edward R. T. Tiekink 《应用有机金属化学》2004,18(3):139-140
The centrosymmetric structure of {Cd[S2CN(CH2Ph)2]2}2 features both bridging and chelating dithiocarbamate ligands so that a square pyramidal S5 coordination geometry results. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
14.
Zhi‐Yong Huang Jin‐Can Shen Zhi‐Xia Zhuang Xiao‐Ru Wang Frank S. C. Lee 《应用有机金属化学》2004,18(6):255-261
Cinnabar, as one of the most widely used mineral drugs in traditional Chinese medicines, has been proven to have prominent curative effects in clinical use for more than 2000 years. But the safety and toxicity of the drug has been under constant debate in clinic usage. Metallothionein (MT) contains about 30% of cysteine in the molecule, and plays an important detoxification role against heavy metals. In this study, it was used as a biomarker to assess mercurial accumulation in rats fed orally with cinnabar. After feeding rats with cinnabar by gastric gavage at different dosages and at different times, the distribution of heavy metals (including mercury, copper and zinc) and MT was investigated among rat tissues, including liver, kidney, heart, brain, testis and blood. Metals and MT determinations were carried out using inductively coupled plasma mass spectrometry (ICP‐MS) and a modified mercury saturation assay technique respectively. The results indicated that mercury was easily accumulated in the tissues of rats exposed to cinnabar, especially in kidney. For example: at a feeding dosage of 5 g kg?1 (bw) for 4 weeks, the mercury concentrations in kidney were 13, 8.7, 21.6 and 26 times those in liver, testis, brain and heart respectively; and at 2.5 g kg?1 (bw) for 2 weeks, the mercury concentrations in kidney were 21, 2.1, 3 and 21 times those in liver, testis, brain and heart respectively. In addition, mercury in kidney and liver of all cinnabar groups was significantly higher than that of the control group (P < 0.01). A high positive correlation observed between MT concentrations and mercury levels in both liver and kidney (R2 = 0.9299, P < 0.02 for liver; R2 = 0.9923, P < 0.0008 for kidney) indicated that MT could be used as a biomarker for mercury in tissues. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
15.
采用MTT比色法对体外培养的肿瘤细胞进行细胞毒作用实验,验证槲寄生蛋白注射液体外抗肿瘤效果.并且鉴定这种检测方法的有效性。实验结果表明槲寄生蛋白注射液有一定的体外抗肿瘤效果;MTT比色法是一种可用的体外细胞毒作用检测法,为新药品的开发提供了实验依据。 相似文献
16.
Ordered intermetallic PtSb had been synthesized by arc-melted and then sintering treatment. The electro-oxidation of liquid methanol on PtSb was investigated at room temperature by cyclic voltammetry and chronoamperometry. The results are compared to those at a polycrystalline platinum electrode surface. It was found that PtSb intermetallic was catalytically more active than pure platinum according to the onset potential and current density. X-ray diffraction (XRD) and XPS technologies had been used to investigate the crystal structure and electron effect. 相似文献
17.
Retraction: The following article from Biomedical Chromatography, “Determination of scutellarin isomer, a predominant metabolite of scutellarin, in human plasma by HPLC/tandem mass spectrometry and its application to the pharmacokinetic study in Chinese healthy volunteers” by Chun‐hua Xia, Yu‐qing Xiong, and Guang‐ji Wang, published online on 21 June 2007 in Wiley Interscience (www.interscience.wiley.com/journal/bmc), has been retracted at the authors' request. 相似文献
18.
A novel route for waste water treatment: photo-assisted Fenton degradation of dye pollutants accumulated in natural polyelectrolyte microshells 总被引:2,自引:0,他引:2
The efficient accumulation of dyes in constructed natural polyelectrolyte microshells under moderate conditions, combined with the photo-assisted Fenton reagent, opens a new route for the effective elimination of dye pollutants from waste water. 相似文献
19.
在这篇文章中, 作者研究涉及凹凸非线性项的Kirchhoff型问题-(a + b ∫R3|▽u|2dx) Δu + λV (x)u = μf(x)|u|q?2u + |u|p?2u, x ∈ R3,u ∈ H1(R3),其中a,b > 0 是常数, λ, μ > 0 是参数, 1 < q < 2, 4 < p < 6 且 V 是一个非负连续位势. 在f(x) 和 V 的合适条件下,此问题正解的存在性和集中性能够通过Nehari 流形和Ekeland 变分原理得到. 相似文献
20.
K. W. Cheah L. C. Ho J. B. Xia J. Li W. H. Zheng W. R. Zhuang Q. M. Wang 《Applied Physics A: Materials Science & Processing》1995,60(6):601-606
Photoluminescence studies on porous silicon show that there are luminescence centers present in the surface states. By taking photoluminescence spectra of porous silicon with respect to temperature, a distinct peak can be observed in the temperature range 100–150 K. Both linear and nonlinear relationships were observed between excitation laser power and the photoluminescence intensity within this temperature range. In addition, there was a tendency for the photoluminescence peak to red shift at low temperature as well as at low excitation power. This is interpreted as indicating that the lower energy transition becomes dominant at low temperature and excitation power. The presence of these luminescence centers can be explained in terms of porous silicon as a mixture of silicon clusters and wires in which quantum confinement along with surface passivation would cause a mixing of andX band structure between the surface states and the bulk. This mixing would allow the formation of luminescence centers. 相似文献