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101.
每一个Jordan代数都对应了一个Tits-Kantor-Koecher李代数.在扩张仿射李代数的分类中[1],A_1型李代数的分类依赖于欧氏空间上半格给出的Tits-Kantor-Koecher李代数.另外在相似的意义下,二维欧氏空间R~2中只有两个半格.设S是R~2上的任一半格,T(S)为半格S对应的Jordan代数,G(T(S))为相应的Tits-Kantor-Koecher李代数.利用Wakimoto自由场的方法给出李代数G(T(S))的一类顶点表示. 相似文献
102.
研究了1,9-双(1-苯基-3-甲基-5-氧代吡唑-4-基)壬二酮-[1,9](BPMPND,H2A)与三辛基氧膦(TOPO,B)的氯仿溶液,从硝酸介质中对La(Ⅲ)、Dy(Ⅲ)的协同萃取,计算了体系的酸性协萃系数RA和协萃系数R,用斜率法测得协萃合物的组成为LaA·HA·B和DyA·HA·B,计算了协萃平衡常数,研究了温度对协萃反应的影响,用萃取法制得了固态协萃合物,并对其组成、IR及TG-DTA进行了研究. 相似文献
103.
104.
Renming Liu Yang Xiong Weiyue Tang Yan Guo Xinhui Yan Minzhen Si 《Journal of Raman spectroscopy : JRS》2013,44(3):362-369
A near‐infrared surface‐enhanced Raman spectroscopy (NIR‐SERS) method was employed for oxyheamoglobin (OxyHb) detection to develop a simple blood test for liver cancer detection. Polyvinyl alcohol protected silver nanofilm (PVA‐Ag nanofilm) used as the NIR‐SERS active substrate to enhance the Raman scattering signals of OxyHb. High quality NIR‐SERS spectrum from OxyHb adsorbed on PVA‐Ag nanofilm can be obtained within 16 s using a portable Raman spectrometer. NIR‐SERS measurements were performed on OxyHb samples of healthy volunteers (control subjects, n = 30), patients (n = 40) with confirmed liver cancer (stage I, II and III) and the liver cancer patients after surgery (n = 30). Meanwhile, the tentative assignments of the Raman bands in the measured NIR‐SERS spectra were performed, and the results suggested cancer specific changes on molecule level, including a decrease in the relative concentrations and the percentage of aromatic amino acids of OxyHb, changes of the vibration modes of the CaHm group and pyrrole ring of OxyHb of liver cancer patients. In this paper, principal component analysis (PCA) combined with independent sample T test analysis of the measured NIR‐SERS spectra separated the spectral features of the two groups into two distinct clusters with the sensitivity of 95.0% and the specificity of 85.7%. Meanwhile, the recovery situations of the liver cancer patients after surgery were also assessed using the method of discriminant analysis‐predicting group membership based on PCA. The results show that 26.7% surgeried liver cancer patients were distinguished as the normal subjects and 63.3% were distinguished into the cancer. Our study demonstrated great potentials for developing NIR‐SERS OxyHb analysis into a novel clinical tool for non‐invasive detection of liver cancers. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
105.
Semi-coloring is a new type of edge coloring of graphs. In this note, we show that every graph has a semi-coloring. This answers a problem, posed by Daniely and Linial, in affirmative. It implies that every r-regular graph has at least ${\lceil\frac{r}{2}\rceil}$ different {K 2, C i | i ≥ 3}-factors. 相似文献
106.
Kong Liu Shengchun Qu Xinhui Zhang Furui Tan Yu Bi Shudi Lu Zhanguo Wang 《Applied Physics A: Materials Science & Processing》2014,114(3):765-768
We fabricated sulfur-doped black silicon by metal-assist chemical etching (MCE) and ion implanting. The morphologies of silicon nanowire (SiNW) arrays and the concentration of sulfur in black silicon were analyzed by scanning electron microscope (SEM). Sulfur-doped black silicon shows higher absorption in entire 0.3–2.5 μm wavelength range as compared to undoped SiNW arrays and flat silicon. The changes in the absorption spectra of black silicon with different etching durations and annealing temperature are also shown. Upon annealing, the absorption decreases significantly in 2–2.5 μm wavelength region. The novel results clearly indicate that sulfur implanting could produce below band gap absorption in the silicon substrate. 相似文献
107.
Xinhui Si Liancun Zheng Xinxin Zhang Ying Chao 《Central European Journal of Physics》2011,9(3):825-834
The flow of a micropolar fluid in a porous channel with expanding or contracting walls is investigated. The governing equations
are reduced to ordinary ones by using similar transformations. Homotopy analysis method (HAM) is employed to obtain the expressions
for the velocity fields and microrotation fields. Graphs are sketched for the effects of some values of parameters, especially
the expansion ratio, on the velocity and microrotation fields and associated dynamic characteristics are analyzed in detail. 相似文献
108.
Dingkang Wang Ming Wang Kaixuan Chen Yujian You Jing Zhang Xinhui Zhou Wei Huang 《应用有机金属化学》2020,34(8):e5692
Fluorescent coordination polymers have drawn extensive attention in sensing applications. Herein, we report a carbazole-based one-dimensional coordination polymer [CdL(H2O)(DMF)2]·DMF ( CdL , H2L = 9H-carbazole-2,7-dicarboxylic acid, DMF = N,N-dimethylformamide). In CdL , each Cd2+ ion is four-bridged by carboxylates, which is further linked by the carbazole units to form a one-dimensional Cd–O–C chains along the c-axis. CdL displays high water stability in the pH range of 3–10. Luminescence experiments indicate that CdL could selectively detect Fe3+ during the concentration range of 0–0.1 mm in water with a Ksv of 8022 m −1 and picric acid (PA) within the concentration range of 0–0.05 mm in methanol solution with a Ksv of 17948 m −1 respectively. The above results reveal that CdL can be applied as a multiresponse luminescence sensor for selectively sensing for Fe3+ in water and PA in methanol solution. 相似文献
109.
Zhipeng Liu Ming Wang Kaixuan Chen Baolin Liu Dingkang Wang Yujian You Xinhui Zhou Wei Huang 《应用有机金属化学》2020,34(4):e5477
Four coordination polymers (CPs), [Cd(2,7-dpfo)2(NO3)2(CH3OH)]n (1) , [Zn(2,7-dpfo)(NO3)(CH3COO)]n (2) , [Co(2,7-dpfo)2(H2L)]n (3) , and [Ni(2,7-dpfo)2(H2L)]n (4) (where 2,7-dpfo is 2,7-di(pyridin-4-yl)-9H-fluoren-9-one and H4L is 1,1′:4′,1′′-terphenyl-4,2′,5′,4′′-tetracarboxylic acid), were synthesized and structurally characterized. Compounds 1 – 4 were determined by elemental analyses, single crystal X-ray diffraction analyses, powder X-ray diffraction, infrared spectroscopy, and thermogravimetric analyses. Compound 1 displays a one-dimensional (1D) zigzag chain structure, while compound 2 possesses a 1D ladder chain structure. Compounds 3 and 4 are isostructural and consist of 1D chains. The solid-state luminescent properties of 1 and 2 and the magnetic properties of 3 and 4 were also investigated. 相似文献
110.
SMA/蒙脱石纳米复合材料增容PA6/ABS共混体系 总被引:1,自引:0,他引:1
采用原位插层法制备苯乙烯-马来酸酐交替共聚物/蒙脱石(SMA/MMT)纳米复合材料增容PA6/ABS共混体系,并与SMA及MMT的增容效果进行比较,运用TEM、SEM、DSC及XRD研究了增容剂SMA/MMT及MMT的增容机理.结果表明,采用SMA做增容剂,体系机械性能下降;MMT可使体系拉伸强度提高,但冲击强度下降;采用SMA/MMT纳米复合材料做为增容剂,可提高共混体系的强度及韧性.TEM、XRD、DSC及SEM研究结果表明,PA6/ABS/(SMA-MMT)体系中MMT主要分布于两相界面处,ABS及PA6分子链可进入MMT层间,形成类似于共聚物结构,起到增容剂的作用,从而降低分散相粒径,增加两相界面作用力,有利于体系力学性能的提高.PA6/ABS/MMT体系中MMT主要分布于连续相PA6中,虽然对分散相粒径影响较小,但增强了PA6相强度,使得体系力学性能提高. 相似文献