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871.
含双二苯基膦甲烷铜(Ⅰ)配合物的研究进展   总被引:4,自引:0,他引:4       下载免费PDF全文
本文概述了含双二苯基膦甲烷铜(Ⅰ)配合物的化学进展,总结了配合物的合成方法:置换法、还原法、电化学方法和直接加成法,全面论述了双核、三核、多核和异核配合物的结构特征,探讨了该类配合物的重要荧光性质。  相似文献   
872.
Alternate adsorption of positively charged colloid-Au nanoparticles (nano-Au⊕) and negatively charged hemoglobin (Hb) on L-cysteine (L-cys) modified gold electrode resulted in the assembly of {Hb/nano-Au⊕}n layer-by-layer films/L-cys modified gold electrode. The nano-Au⊕ was characterized by transmission electron micrograph (TEM) and microelectrophoresis. The modified electrode interface morphology was characterized by electrochemical impedance spectroscopy (EIS), atomic force mi- croscopy (AFM), cyclic voltammograms (CV) and chronoamperometry. Direct electron transfer between hemoglobin and gold electrodes was studied, and the apparent Michaelis-Menten constant ( km app) of the modified electrode was evaluated to be 0.10 mmol·L?1. Moreover, the higher activity of proteins in the nano-Au⊕ films could be retained compared with the electropolymerization membrane, since the pro- teins in nano-Au⊕ films retained their near-native structure. Direct electron transfer between hemoglo- bin and electrode and electrochemically catalyzed reduction of hydrogen peroxide on a modified elec- trode was studied, and the linear range was from 2.1×10-8 to 1.2 ×10?3 mol·L-1 (r = 0.994) with a detection limit of 1.1×10-8 mol·L-1 H2O2.  相似文献   
873.
 A GLP study can be performed at more than one site. This is called a multi-site study. Although, the study is performed at different sites, it is still one study and must completely comply with the GLP principles. The fact that different activities are conducted at different sites implies that the planning, the organization and the communication are crucial for the success of the study. This means that all the staff involved should know their responsibilities and should have the knowledge and skills to realize all the phases of the study according to the GLP principles. To achieve a well managed multi-site study, several strategies for setting up such a study can be followed. This paper focuses on the responsibilities, communication, and collaboration of the personnel, which are involved in a multi-site study. Several case studies are highlighted, and we concluded that the basic communication triangle in a single-site GLP study between test facility management, study director, and the quality assurance unit should be extended to the communication among test facility and test site management, study director, principle investigator(s), and the quality assurance units at the test sites. Introduction Received: 14 August 2002 Accepted: 26 November 2002  相似文献   
874.
In search for a cheaper anode catalyst for the oxidation of ethanol for development of direct alcohol fuel cells, Pd has been considered here as an interesting substitute for Pt in Pt Ru binary electrodeposite. The binary catalyst when co-deposited on nickel support has been found to increase the current density and decrease the anodic overvoltage significantly with respect to pure Pt, Pd and Ni. Its electrocatalytic capability is also comparable with that of the Pt-Ru binary electrocatalyst on Ni-support, when studied in 1 M EtOH containing 1 M NaOH solution. The effect of loading of Pd Ru electrocatalyst on Ni support has also been tested. The electrocatalytic activity of the electrodes for oxidation of ethanol has been explained by studies of cyclic voltammetry, chronopotentiometry, steady-state polarization, and conjugated scanning electron microscopy–energy dispersion X-ray spectroscopy. It has been found that electrode containing the higher amount of deposit are less affected by carbonaceous poisons.  相似文献   
875.
The microwave-mediated reaction of 4-aryl-4-oxobutanoic acids with benzylamines furnished 1-arylmethyl-3-[(E)-1-arylmethylidene]-5-phenyl-2,3-dihydro-1H-pyrrolones. This result is in contract to the earlier report on this reaction conducted under neat conditions. Structures for the products were assigned on the basis of spectral data and confirmed by independent synthesis. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 368–373, March, 2007.  相似文献   
876.
CO2部分氧化乙烷制乙烯Pd—Cu/MoO3—SiO2催化剂的研究   总被引:7,自引:0,他引:7  
李青  钟顺和 《应用化学》1998,15(6):49-52
用化学吸附-红外光谱、化学吸附-程序升温脱附(TPD)和微型反应技术研究了Pd-Cu/MoO3-SiO2(MoSO)催化剂对CO2和乙烷的吸附活化和部分氧化反应性能.结果表明,乙烷以C—H键中的H吸附于MoSO载体表面MoO键的端基氧上;Pd-Cu/MoSO催化剂对CO2有良好的化学吸附活化性能,CO2的吸附除有线式吸附态和剪式吸附态外,还有一种新的卧式吸附态;Pd-Cu/MoSO催化剂的晶格氧参与了化学反应.探讨了在Pd-Cu/MoSO催化剂上CO2的部分氧化乙烷反应机理  相似文献   
877.
Li C  Wang X  Peng Q  Li Y 《Inorganic chemistry》2005,44(19):6641-6645
Mn2P2S6 single-crystal nanorods with diameters 20-40 nm and lengths up to 1 microm and nanotubes with diameters 40-50 nm and lengths ranging between 110 and 170 nm have been prepared through a low-temperature solvothermal method. They have been characterized by X-ray diffraction, transmission electron microscopy (TEM), high-resolution (HR) TEM, electron diffraction, energy-dispersive spectrometry analysis, X-ray photoelectron spectroscopy, and Raman spectroscopy.  相似文献   
878.
利用水热合成技术成功制备出一种新型多钒硼氧化合物, 用X射线单晶衍射分析技术对其晶体结构和分子结构进行了确定。结果表明在该化合物中多钒硼氧阴离子具有一个新颖的三明治结构。上下两个结构单元都是由六个VO5四角锥交替地通过顺式和反式共边的方式连接起来构成的一个钒氧三角形结构。中间的结构单元是由BO3平面三角形和BO4四面体以共角的方式相互连接形成的一个折叠型的B18O36(OH)6环。三明治结构中层与层之间通过桥氧相连。一个水分子处于它的核心位置上,与每个VO5四角锥中的钒原子都保持几乎相等的距离。该化合物及其晶体中存在着丰富的化学结构和成键信息,同时也有作为氧化还原反应催化剂的潜能。  相似文献   
879.
A new isoprenyl phenyl ether, 3-hydroxy-4-(3-methylbut-2-enyloxy)benzoic acid methyl ester (1), together with 4-hydroxybenzoic acid (2), 2-hydroxy-6-methylbenzoic acid (3), and 4-hydroxy-3-methoxybenzoic acid (4) were isolated from Mangrove fungus (No. B60) from the South China Sea. The structures of the compounds were established on the basis of NMR spectroscopic and mass spectrometric data. In the preliminary bioassay, compound 1 exhibited antibacterial and antifungal activities. Compound 1 also inhibited cytotoxicity to the hepG2 cell line with an IC50 value of 10.0 μg/mL. Published in Khimiya Prirodnykh Soedinenii, No. 4, pp. 313–314, July–August, 2007.  相似文献   
880.
A global forcing set in a simple connected graph G with a perfect matching is any subset S of E(G) such that the restriction of the characteristic function of perfect matchings of G on S is an injection. The number of edges in a global forcing set of the smallest cardinality is called the global forcing number of G. In this paper we prove several results concerning global forcing sets and numbers of benzenoid graphs. In particular, we prove that all catacondensed benzenoids and catafused coronoids with n hexagons have the global forcing number equal to n, and that for pericondensed benzenoids the global forcing number is always strictly smaller than the number of hexagons.  相似文献   
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