Hydrolysis of 2-aminoethanethiolsulfate ions

The kinetics of the acid catalyzed hydrolysis of 2-aminoethanethiolsulfate (AETS) ions were investigated. The dependence of the hydrolysis rate constant on acidity and temperature was determined. The hydrolysis rate equation can be expressed as where H_o is the Hammett acidity function. The rate constant, k, can be expressed as The pK_a's for the compound were measured and literature value of pK_a was found to be in error. The values determined in this study are pK_a1 < ?0.5 and pK_a2 = 9.1 ± 0.1. General acid catalysis of the hydrolysis reaction was found not to proceed to a significant degree. © 1994 John Wiley & Sons, Inc.

1 This article is a US Government work and, as such, is in the public domain in the United States of America.

     

Synthesis and Structureof［（C_2H_5）_4N］［Mo_3（μ_3－O）（μ－Cl）_3（μ－CH_3CH_2COO）_3Cl_3］

ＳｙｎｔｈｅｓｉｓａｎｄＳｔｒｕｃｔｕｒｅｏｆ［（Ｃ_２Ｈ_５）_４Ｎ］［Ｍｏ_３（μ_３－Ｏ）（μ－Ｃｌ）_３（μ－ＣＨ_３ＣＨ_２ＣＯＯ）_３Ｃｌ_３］ＺｈｕａｎｇＨｏｎｇ－Ｈｕｉ；ＷｕＤｉｎｇ－Ｍｉｎｇ；ＨｕａｎｇＪｉａｎ－Ｑｕａｎ；ＨｕａｎｇＪｉｎ－Ｌ...     

An order-disorder transition in Sr2IrD5: Evidence for square pyramidal IrD5 units from powder neutron diffraction data

Neutron diffraction data have been collected on a powdered sample of Sr₂IrD₅ over a range of temperatures. The compound, which is cubic at room temperature, has been found to exhibit a gradual transformation to a tetragonal phase in the temperature range 200-140 K. As a result of the transition, deuterium atoms which randomly occupy sixfold positions in the cubic phase, become tetragonally ordered. A small fraction of the cubic phase remained untransformed at 4.2 K. Both the cubic and tetragonal structures are consistent with square pyramidal IrD₅ units with average Ir---D distances of 1.714 and 1.718 Å, respectively. Agreement factors, R₁, for the two structural analyses are 3.44 and 4.94%.     

含(R)或(S)-1,1′-联萘和噁二唑单元的手性高分子合成与性质研究

在Pd(PPh3)4催化下,将单体(S)-6,6′-二溴-2,2′-二正丁氧基-1,1′-联萘[(S)-M-1]和(R)-6,6′-二溴-2,2′-二正丁氧基-1,1′-联萘[(R)-M-1]分别与2,5-二(4-三正丁基锡基苯)-1,3,4-噁二唑(M-2)通过Stille交叉耦合反应合成了手性高分子P-1与P-2,并用1HNMR、13CNMR、FTIR、UV、热分析、荧光光谱、GPC和CD等分析方法进行了表征.手性高分子P-1和P-2都能发射较强的蓝色荧光;在高分子侧链上引入丁氧基后使得手性高分子的溶解性能增强,并具有良好的成膜性能;在高分子主链引入亲电子的噁二唑生色团能使其特别适合于作为空穴电子传输层,对氧和热特别稳定,是一类潜在的光电高分子材料.     

The Reaction and Applied Study of the Amide and P_2S_5

It is usually reported that reaction between carbonyl and P2S5 produce thiono group compound. The Products from carbonyl after ammonolysis and hydrazinolysis have the very import applied value in the synthesize of heterocyclic compound. Sulfuration reation if a nucleophilic attack, SPS2 anionsid obtained from P2S5 in the organic sovent, rather easier than thereationsof scheeren’s reagent. The reation mechanism is as follows: The reation speed has something todo with the electronegative of…     

Synthesis,Structure and Adsorption of AlPO-21 Prepared by Co-template Method

IntroductionAlPO 2 1isatypeofmicroporousaluminophosphatepreparedbyFlanigenandco workersin 1982 ,andthestructurewasresolvedbySmithetal.1in 1984 .AlmostatthesametimePariseetal.2 preparedAlPO 2 1phasebyanotherrouteandresolvedthestructureindependently .Inthenextyear ,GaPO 2 1phasewasobtainedaswell.3Al thoughAl(Ga)PO 2 1phasespreparedindifferentwayspossesssimilarchannelsystem ,amongthemtherearestillsomedifferencesinlatticeconstants ,indicatingthatdiffer enttemplatemoleculescanaffectlocallythe…     

The application of the concept of reaction layer to the study of electrode processes coupled with the second-order chemical reactions at microelectrodes under steady-state conditions

Under steady-state conditions, the current equations of the second-order EC, ECE and DISPI reactions at microdisk, microspherical and microring electrodes are derived with the aid of the concept of the reaction layer. The conditions under which these equations would be valid are also discussed. Using these equations, methods to determine the kinetic parameters for the second-order EC, ECE and DISPI reactions are presented. The reduction of 2,6-diphenyl-pyrylium cation and oxidation of triphenylamine were investigated as examples of the second-order EC and ECE reactions.     

Improving MCM‐41 as a Nitrosamines Trap through a One‐Pot Synthesis

Copper oxide was incorporated into MCM‐41 by a one‐pot synthesis under acidic conditions to prepare a new mesoporous nitrosamines trap for protection of the environment. The resulting composites were characterized by XRD, N₂ adsorption–desorption, and H₂ temperature‐programmed reduction techniques, and their adsorption capabilities were assessed in the gaseous adsorption of N‐nitrosopyrrolidine (NPYR). The adsorption isotherms were consistent with the Freundlich equation. The copper salt was deposited onto MCM‐41 during the evaporation stage and was fixed on the host in the calcination process that followed. MCM‐41 was able to capture NPYR in air below 373 K but not at 453 K. Loading of copper oxide on MCM‐41 greatly improved its adsorption capability at elevated temperatures. The influence of the incorporation of copper into MCM‐41 samples and the adsorption behavior of these samples are discussed in detail.