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991.
依波西隆蓝与蛋白质作用的共振光散射光谱及其分析应用   总被引:9,自引:0,他引:9  
微量蛋白质对依波西隆蓝的共振光散射产生增强作用,且增强程度与蛋白质浓度有良好的线性关系,由此建立了测定蛋白质的灵敏共振光散射分析方法。利用该方法测定合成样品和血清样品中的蛋白质,均获得了可靠的分析结果。  相似文献   
992.
钯的高选择性流动注射分析方法的研究   总被引:2,自引:0,他引:2  
Pd(Ⅱ)与DBC-偶氮氯膦在硫酸介质中经加热发生络合显色反应,将此显色反应与流动注射分析技术结合,研究了影响该流动注射显色体系的各种因素,建立了钯的流动注射分析方法.用该方法可不经分离直接测定二次阳极泥和氯化渣中的钯.  相似文献   
993.
The complexing process proceeding in the NiII–thiocarbohydrazide (H2N–H–NC(=S)–NH–NH2)–propanone triple system in EtOH solution and nickel(II)hexacyanoferrate(II) gelatin-immobilized matrix has been studied. It has been found that in the first case, template synthesis leading, as a minimum, to formation of three coordination compounds of NiII with (N,N,S,S)-donor tetradentate ligands having NiL1, NiL2 and NiL3compositions where L1 is 4,6,6-trimethyl-2,3,7,8-tetraazanonen-3-di(thiohydrazide)-1,9, L2 is 4,6,6,12-tetrametyl-1,9-dithio-2,3,7,8,10,11-hexaazatridekadien-3,11-hydrazide-1 and L3 is 2,8,10,10,16-pentamethyl-5,13-dithio-3,4,6,7,11,12,14,15-octaazaheptadekatrien-2,7,15 is observed, whereas in the gelatin-immobilized matrix, a complexing process in the system considered does not occur.  相似文献   
994.
电化学法测定几种稀土贮氢合金的热力学函数   总被引:14,自引:0,他引:14  
贮氢材料由于能可逆地吸放氢,得到了广泛地应用.特别是以贮氢材料为负极制成的氢镍二次电池,容量为同类型镉镍电池的1.5~2倍,且电压又相近,是镉镍电池的理想换代产品,受到人们普遍的关注。LaNi_(4.5)Mn_(0.5),LaNi_(4.9)Sn_(0.1)和La_(0.8)Nd_(0.2)Ni_(2.5)Co_(2.4)Al_(0.1)是电化学性能较优越的贮氢合金。LaNi_(4.5)Mn_(0.5)的电化学容量高,理论容量可达400mAh.g~(-1).LaNi_(4.9)Sn_(0.1)和La_(0.8) Nd_(0.2)  相似文献   
995.
水杨酸分子印迹分离介质的水相制备及色谱行为   总被引:7,自引:0,他引:7  
以水杨酸为模板分子,2-乙烯基吡啶为功能单体,在甲醇/水体系中制备了水杨酸分子印迹聚合物,并将其作为高效液色谱分离介质研究了其对水杨酸及水杨酸的位置异物体———对羟基苯甲酸的色谱行为。结果表明,该聚合物固定相表现出良好的分离选择性,能够使水杨酸与对羟基苯甲酸快速基线分离。通过对流动相组成与色谱分离效果关系的探讨,证实溶质与印迹固定相的疏水相互作用是分子识别的主要作用力。  相似文献   
996.
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   
997.
Reactions of CsI and HgI2 with benzo-15-crown-5 (B15C5) and 15-crown-5 (15C5) in an ethanol-acetone mixture produced [Cs(B15C5)2]2[Hg2I6] (1) and {[Cs(15C5)]2[Hg2I6]}n (2), respectively. The structures of the two complexes are quite different. Molar ratios of Cs+ : crown ether are 1 : 2 in 1 and 1 : 1 in 2. Complex 1 consists of two Cs(B15C5) 2 + cations and a Hg2I 6 2- anion. Cs+ lies between the two crown-5 ligands, resulting in a sandwich-type cation. Cationic Cs(B15C5) 2 + and anionic Hg2I 6 2- are linked together by electrostatic interactions and the complex 1 is an ion pair compound. Complex 2 consists of infinite [Cs(15C5)]2[Hg2I6] units. Each structural unit contains two Cs(15C5)+ cations and a Hg2I 6 2- anion. Cs+ is coordinated by five oxygen atoms of 15C5, three iodine atoms of Hg2I 6 2- , and an iodine atom of Hg2I 6 2- in an adjacent structural unit. The interactions between the Cs+ of Cs(15C5)+ and an I in Hg2I 6 2- from adjacent structural units polymerize the complex 2, resulting in a one-dimensional network structure. The anions of Hg2I 6 2- in both complexes are similar. The two mercury atoms are linked through two bridging iodine atoms and each mercury is also coordinated by two terminal iodines. Crystal data for 1: space group P21/c (No. 14), a = 12.253(4), b = 20.945(7), c = 16.110(6) Å, = 111.0(1)°, V = 3860 Å3, Z = 4, R = 0.082 (R w = 0.089). Crystal data for 2: space group P21/c (No. 14), a = 12.157(4), b = 8.546(4), c = 20.666(6) Å, = 91.54(3)°, V = 2146 Å3, Z = 4, R = 0.034 (R w = 0.048).  相似文献   
998.
 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   
999.
在低钯含量活性非均布Pd/Al2O3催化剂上,实现了富氧条件下,氢部分选择性催化还原NO过程,低温、富氧条件下NO的转化率高达80%-100%。NO直接分解实验表明,600℃,NO分解转化率在无氧时为17.3%,有0.5%氧存在时接近于0。氢非选择性还原NO条件下,100℃以下,NO转化率为100%。根据实验结果及文献,推测了氢部分选择性还原NO过程中可能存在的反应,不同的反应温度下,NO脱除反应有所不同。在115℃以下,NO还原产物为NH3;115℃-155℃,NO还原产物为NH3、N2O和N2;155℃以上,NO还原产物中无NH3存在。NO还原反应与氢氧反应是平行的竞争反应。  相似文献   
1000.
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   
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