含葡萄糖基水溶性硫化黑的合成

本文以C．I．硫化黑1为原料，经葡萄糖还原成隐色体后，再与葡萄糖缩合，合成出含葡萄糖基水溶性硫化黑。合成方法分别采用了焙烘法和水介质中合成。结果表明，水介质中合成的含葡萄糖基水溶性硫化黑溶解度好于焙烘法。     

新型水暂溶性分散染料的研究

随着涤纶纤维的发展,分散染料得到了广泛的应用。传统的涤纶用分散染料由于其分子结构中不含水溶性基团,因而在使用时必须加入分散剂进行砂磨,才能在水介质中染涤纶纤维。因此,分散染料的商品化费时、费工和消耗分散剂。七十年代中期,国外不少染料工作者企图在分散染料结构中引进水溶性基团。在应用时,水溶性基团脱落、分解或闭环,转变为非水溶性结构而上染纤维。这些染料的合成主要以传统的分散染料为母体,经过化学处理     

水溶性姜黄色素的提取及其理化性质研究

从姜黄茎块中提取制备水溶性姜黄色素，研究了姜黄色素的光稳定性、热稳定性及其介质条件对吸光度的影响。     

水溶性姜黄色素的提取及其理化性质研究

从姜黄茎块中提取制备水溶性姜黄色素，研究了姜黄色素的光稳定性、热稳定性及其介质条件对吸光度的影响。     

含葡萄糖基水溶性硫化黑的合成

本文以C.I.硫化黑1为原料,经葡萄糖还原成隐色体后,再与葡萄糖缩合,合成出含葡萄糖基水溶性硫化黑。合成方法分别采用了焙烘法和水介质中合成。结果表明,水介质中合成的含葡萄糖基水溶性硫化黑溶解度好于焙烘法。     

四氟丙酸钠的合成研究

四氟乙烯与氰化钠在水和水溶性有机溶剂组成的反应体系中进行亲核加成反应，继而在碱性介质中水解生成四氟丙酸钠。论述了影响其合成的诸因素。     

羧甲基淀粉钠合成工艺研究

研究了以平方米淀粉、氯乙酸为原料，乙醇为介质，用氢氧化钠水溶液为酸接受剂，经羧甲基化作用制得粉末状水溶性的高取人蔗、高粘度的羧甲基淀粉的（ＣＭＳ），并讨论了合成原理及产品质量的各种因素。     

咪唑啉酰胺在HCl-H_2S腐蚀介质中对低碳钢(A_3)的缓蚀作用

利用极化曲线法和扫描电镜分析对不同浓度水溶性咪唑啉酰胺缓蚀剂在1000mg/L HCl+500mg/L H2S腐蚀介质中对低碳钢(A3)的缓蚀作用进行了研究。结果表明:在HCl-H2S腐蚀介质中,加入浓度为15mg/L时,水溶性咪唑啉酰胺缓蚀剂对低碳钢(A3)具有很好的缓蚀作用。     

水溶性咪唑啉酰胺对A3钢的缓蚀性能研究

利用GaussView 6和Gaussian 16软件对水溶性咪唑啉酰胺分子进行结构优化,通过轨道能量计算得到能量差,根据能量差揭示其缓蚀机理,并进一步揭示了水溶性咪唑啉酰胺对A3钢的缓蚀机理。同时,采用旋转挂片实验、电化学方法和扫描电子显微镜分析研究了水溶性咪唑啉酰胺在盐酸介质中对A3钢的缓蚀性能。结果表明,在腐蚀介质为1 mol/L的稀盐酸溶液中,(45±1)℃条件下,水溶性咪唑啉酰胺最佳加入量为15 mg/L,缓蚀率高达96.8%;电化学实验极化曲线与旋转挂片实验结果一致,通过扫描电镜可以看出,水溶性咪唑啉酰胺对A3钢具有显著的缓蚀效果。     

新型水溶性壳聚糖衍生物的制备

以醋酸和丙酮为反应介质,利用马来酸酐在均相条件下对壳聚糖进行水溶性N-酰化改性;与壳聚糖相比,改性后的壳聚糖衍生物的水溶性有了很大改善。实验表明：对壳聚糖的N-酰化改性程度越高,其改性产物的水溶性越好;同时,制备的3种样品的产率均在90％以上。     

Thermal degradation of poly(vinyl chloride): The accelerating effect of hydrogen chloride

The effect of hydrogen chloride on the decomposition of poly(vinyl chloride) (PVC) has been studied and a mechanism for the autocatalysis is given. The chloride ion formed upon dissociation of the hydrogen chloride is a strong base in the medium of the reaction, and hence constitutes the active species. Therefore, the acceleration of the decomposition of PVC can be prevented by either removing the free acid from the system with the aid of an acid acceptor or adding a complexing agent such as ferric chloride.     

Thermogravimetric study on catalytic hydropyrolysis of coal

A number of catalysts have been tested on coal under hydropyrolysis conditions. For tin(II) chloride and zinc chloride, the most effective catalysts, the influences of hydrogen pressure, heating rate and loading on the total conversion and the conversion rates have been examined. The results can be interpreted as a thermally induced formation of free radicals in the first step and a catalysed stabilization of free radicals by hydrogen in the second step. The influence of the tin and zinc chlorides also on the first reaction step is obvious. Zinc chloride is observed to undergo a deactivation caused by a still unknown side reaction.     

State of hydrogen electrochemically stored using nanoporous carbons as negative electrode materials in an aqueous medium

Nanoporous carbons were used as negative electrode material in aqueous KOH medium to store hydrogen by electrodecomposition of water at atmospheric pressure. The storage capacity by this process is approximately one order of magnitude higher than in the gas phase at ambient conditions. By considering the particularities of the electrochemical characteristics, this paper gives information on the mechanism and on the kind of bond between hydrogen and the carbon host. For most experiments, a self-standing porous carbon cloth electrode has been used in order to avoid any side effect which could be due to additives. After galvanostatic hydrogen charging, the carbon material was analyzed by galvanostatic discharge and temperature-programmed desorption in order to determine the nature of the carbon-hydrogen bond and the amount of hydrogen sorbed. The activation energy for hydrogen desorption was estimated to be 110 kJ/mol, that confirms a weak chemical character of the hydrogen-carbon bond. Although the bond is stronger than in the case of physisorption, the fraction of hydrogen irreversibly trapped is low compared to the reversible fraction. Finally, we show that the reversible capacity can be significantly enhanced by increasing the temperature to 60 °C during the electrochemical reduction of water. The well-defined plateau during the oxidation step demonstrates high potentialities of this technique for electrochemical energy storage in nanoporous carbons using an aqueous medium.     

Modélisation de la cinétique d'hydrolyse de dérivés poly(métha)acryliques et styréniques. Application à l'étude des polymères supports

Reactions of hindered amines with acryloyl chloride or methacryloyl chloride provide acrylic and methacrylic amides. An ester of acrylic acid can also be synthesized by reaction of a substituted benzylic alcohol such as 2,4-dichlorobenzyl alcohol, as well as a styrenic ester by reaction of benzoic acid with vinylbenzyl chloride. These monomers, except the methacrylic amides, were able to be polymerized and their hydrolyses in acidic or basic medium were studied. The step that limits the overall rate of the process is the diffusion of hydrolysis product through the polymer matrix. A modelling of this release, based on a mass transfer coefficient, was also proposed. The model could be used for many hydrolysis reactions of amorphous polymers in heterogeneous medium.     

The stability and dynamics of a gas-liquid reactor

Experiments are reported on the reaction of methanol vapour with hydrogen chloride to give methyl chloride and water in a two phase stirred tank reactor. The reactants enter and the products leave, as vapours but the reaction takes place in a concentrated aqueous solution of zinc chloride. The system may reach a steady state, display limit-cycle behaviour or overflow depending on the conditions. A theoretical analysis indicates that one or two equilibrium points can occur which have dynamic characteristics in accord with the observed behaviour. In applying Bendixson's Theorem particular attention must be paid to the boundedness constraints.     

Photoassisted deposition of rhodium on platinum/titania samples as a method of preparing bimetallic catalysts

Rh-Pt/TiO₂ samples obtained by UV illumination at room temperature in the absence of oxygen of suspensions in aqueous Rh³⁺ solutions of particulate 2.5 wt.-% Pt/TiO₂ (previously prepared by impregnation and reduction in hydrogen), were examined by X-ray photoelectron spectroscopy and transmission and scanning transmission electron microscopy. Depending on the medium (water, 2-propanol-water, ammonia solution buffered at pH 11 with ammonium chloride or nitrate), rhodium particles (ca. 1 wt.-% loading) of various mean size and degree of reduction were found. Interestingly, rhodium was deposited on titania in neutral medium and on platinum in basic medium. These results, which demonstrate that different types of bimetallic catalysts can be prepared by photoassisted deposition, are discussed in terms of the separation of photoproduced charges and surface charge.     

Removal of Zinc Ions from Aqueous Chloride Solutions by Solvent Extraction Using Alamine 308

Abstract

A study has been undertaken to develop a solvent extraction system for zinc with Alamine 308 in aqueous chloride medium. The parameters investigated included reagent concentration, acid concentration, pH, aqueous to organic phase ratio, and rate of extraction and stripping. The study shows that zinc can be extracted rapidly and efficiently from aqueous chloride solutions. A number of aqueous stripping reagents removed more than 90% of the zinc from the organic phase with only one equilibration.     

Iron(III) Chloride‐Catalysed Aerobic Reduction of Olefins using Aqueous Hydrazine at Ambient Temperature

A chemoselective reduction of olefins and acetylenes is demonstrated by employing catalytic amounts of ferric chloride hexahydrate (FeCl₃⋅6 H₂O) and aqueous hydrazine (NH₂NH₂⋅H₂O) as hydrogen source at room temperature. The reduction is chemoselective and tolerates a variety of reducible functional groups. Unlike other metal‐catalysed reduction methods, the present method employs a minimum amount of aqueous hydrazine (1.5–2 equiv.). Also, the scope of this method is demonstrated in the synthesis of ibuprofen in aqueous medium.     

Degradation of poly(ethylene glycol) by electrolysis during the Cu electroplating: A combined experimental and density functional theory study

The polymer additives are key factor materials in the Cu electroplating process, essential for controlled acceleration and inhibition of Cu deposition. In this study, the degradation behavior of a polymer additive—poly(ethylene glycol) (PEG)—during the Cu electroplating was investigated by MALDI‐TOF MS technique. The PEG was completely degraded after 4 h at a constant electric current density of 13 mA/cm², whereas it showed no degradation without an electric field even at a very low pH (pH < 1). The pathways and energetics of PEG degradation by electrolysis in aqueous chloride medium was investigated using density functional theory calculations at the same time. It demonstrated how facile the decomposition of PEG internal radical is, which is generated via the hydrogen abstraction from PEG by hydroxyl radical formed at the anode in aqueous chloride medium under an electric field. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Some molten ionic oxides as chemical reagents

Molten ionic oxides possess important desirable properties: thermal stability, and useful chemical properties resulting from their acid or basic behaviour, i.e., from their capacity to accept or donate an oxygen ion, and, in several cases, relatively low melting points, well below 1000°c. Bismuth trioxide was found to effect a two-temperature decomposition of ammonium chloride, yielding ammonia and hydrogen chloride. Molten antimony trioxide was found to attack rock phosphate and convert part of the phosphate to a water-soluble form. Molten lead monoxide was found to dissolve calcium oxide readily, to dissolve chromic sesquioxide, to decompose chromite ore and to permit an extraction of iron-free lead chromate into an upper layer of molten alkali chloride. Addition of lead sulphide to a lead monoxide melt caused formation of elemental lead and lead sulphate. Vanadium pentoxide was found to decompose ammonium chloride, yielding first, hydrogen chloride and then, ammonia. The reaction of a vanadium pentoxide melt with rock phosphate, studied in some detail, resulted in water-solubilisation of the phosphate. The product formed in the melt is probably a calcium phosphate vanadate, from the aqueous solution of which calcium can be precipitated by ammonium carbonate; the ensuing ammonium phosphate and vanadate solution can be separated by known methods, permitting recovery of the vanadium pentoxide, and yielding ammonium phosphate.