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201.
Zhi Qiang LIU Qi FANG* Wen Tao YU Gang XUE Du Xia CAO Dong WANG Guang Ming XIA Min Hua JIANG State Key Laboratory of Crystal Materials Shandong University Jinan 《中国化学快报》2002,13(10)
In common fluorescence process, molecular excitation is caused by the absorption of at least a single photon with shorter wavelength. When certain laser is used as the pump source, some compounds can be excited by simultaneous absorption of at least two photons and then the emission of up-converted fluorescence may occur. This process is called two-photon excited fluorescence (TPEF)1,2. Because of several advantages of TPEF, including intrinsic high three-dimensional resolution and the p… 相似文献
202.
采用Ca(2+)选择电极,pH电极和电导电极对钠硼解石水溶液碳化过程进行跟踪测定。实验结果表明:反应分二步进行,反应最终结果是钠硼解石完全分解,硼全部进入溶液并大部分以H3BO3的形式存在,同时考察了温度,气流量对钠硼解石水溶液碳化结果的影响。根据碳化机理,提出了较佳的碳化条件。 相似文献
203.
Dibutyltin(IV) oxide reacts with the cantharidin analogue, 4′-(7-oxabicyclo [2,2,1]-5-heptane-2,3-dicarboximide) benzoic acid, A, to give the complexes [(p-C8H8NO3-C6H4-COOBu2Sn)2O]2 (1) and (p-C8H8NO3-C6H4-COO)2SnBu2 (2) which had been characterized by IR and 1H, 13C, 119Sn NMR. Single X-ray crystal structure analysis has been determined for compound (1), which was analogue to most other [(RCOOBu2Sn)2O]2. The dimer features central of Bu4Sn2O2 unit with the two Bu2Sn groups being linked via bridging oxygen atom. Each tin atom adopts distorted trigonal bipyramidal structures via two carbons from a dibutyl moiety and three oxygen atoms from cantharidin derivative and bridging oxygen atom. In vitro tests show compounds 1 and 2 exhibit high cytotoxicity against P388 and HL-60. 相似文献
204.
A novel assay of γ-globulin (γ-IgG) with a sensitivity at the nanogram level is proposed based on the measurement of enhanced resonance light-scattering (RLS) signals resulting from the interaction of functionalized nano-HgS with γ-globulin. At pH 5.03, the RLS signals of functionalized nano-HgS were greatly enhanced by γ-globulin in the region of 200-700 nm characterized by the peak around 362 nm. Linear relationship can be established between the enhanced RLS intensity and γ-globulin concentration in the range of 10-140 ng ml−1. The limit of detection is 2.71 ng ml−1. Based on this, a new direct quantitative determination method for γ-globulin in blood serum samples without separation of human serum albumin (HSA) is established. The contents of γ-IgG in blood serum samples were determined with recovery of 95.7-102.5% and R.S.D. of 1.6-2.4%. This method is proved to be very sensitive, rapid, simple and tolerance of most interfering substances. 相似文献
206.
Yulu Yang Mingguang Wu Xingwang Zhu Hui Xu Si Ma Yongfeng Zhi Hong Xia Xiaoming Liu Jun Pan Jie-Yinn Tang Siang-Piao Chai Leonardo Palmisano Francesco Parrino Junli Liu Jianzhong Ma Ze-Lin Wang Ling Tan Yu-Fei Zhao Yu-Fei Song Pardeep Singh Pankaj Raizada Deli Jiang Di Li R. A. Geioushy Jizhen Ma Jintao Zhang Song Hu Rongjuan Feng Gang Liu Minghua Liu Zhenhua Li Mingfei Shao Neng Li Jiahe Peng Wee-Jun Ong Nikolay Kornienko Zhenyu Xing Xiujun Fan Jianmin Ma 《中国化学快报》1990,30(12):2065-2088
This roadmap demonstrates a series of two-dimensional nanomaterials, such as graphene, black phosphorus, oxides, layered double hydroxides, chalcogenides, bismuth-based layered compounds, MXenes, metal organic frameworks, covalent organic frameworks, and others, for environmental catalysis. 相似文献
207.
Groups 5 and 6 metal chlorides such as MoCl5, WCI6, NbCl5 and TaCl5 were found to be simple and very efficientcatalysts for the aromatic H/D exchange reactions. Compared with other metal chlorides such as ZnCl2, SnCl4 and TiCl4, groups 5 and 6 metal chlorides showed better catalytic activity in the H/D exchange reaction of naphthalene with C6D6. Deuteration of anthracene using MoC15 as a catalyst proceeded within 24 h at room temperature. Other aromatic compounds such as toluene, diphenylmethane and 1,1,2-triphenylethane were also deuterated smoothly in C6D6 within 24 h at room temperature. 相似文献
208.
水杨基荧光酮—过氧化氢催化动力学光度法测定痕量锇(Ⅳ) 总被引:5,自引:0,他引:5
在碱性介质中,痕量锇(Ⅳ)对水杨基荧光酮(SAF)与过氧化氢的氧化还原反应有显著的催化作用。本文以此为基础,提出用分光光度催化动力学测定痕量锇(Ⅳ)的新方法。本法未加掩蔽剂时的线性范围是0.08-0.80μg/L,加入掩蔽剂后的线性范围是0.08-0.80μg/L,检出限为0.08μg/L。本法用于实际样品中Os(Ⅳ)的测定,结果良好,本实验还测定了此催伦反应的活化能和反应级数。 相似文献
209.
合成了金(Ⅲ)与七种中性氧配体RnXO(R=辛基或苯基;X=N,P,As和S;n=2,3)形成的十种配合物,可概括为两种类型:H(RnXO)x·AuCl_4·Sy(RnXO=TONO、TOPO、TPPO、DOSO、DPSO、TPAsO和bipyO_2;S=乙醇或水;x=1,2,3,y=0,1,2或3)和[Au(L)X_2](L=bipyO_2;X=Cl或Br)。用元素分析、摩尔电导、紫外和红外光谱、核磁共振和热重分析等方法测定了它们的组成和性质,并对其可能的结构也进行了讨论。 相似文献
210.
A new form of edge lithography, edge spreading lithography (ESL), has been demonstrated and applied to the formation of coinage metal rings. In this process, alkanethiols are delivered from a flat PDMS stamp to the surface of a metal film through a two-dimensional array of spherical silica colloids. The thiols further spread on the metal surface, forming highly ordered SAMs in the form of a ring pattern. Following lift-off of beads, the pattern in the SAMs can be transferred into the metal film through wet chemical etching, with SAMs serving as the resist. The dimensions of the rings can be readily controlled by several parameters such as the beads diameter, the concentration of the thiol solution, and the contact time between the stamp and the silica beads. 相似文献