寡聚酸合铜(Ⅱ)配合物的合成及表征

在水-乙醇体系中,以寡聚酸钾与Cu2+离子反应合成寡聚酸合铜(Ⅱ)配合物,采用正交实验,考察了V(水)∶V(乙醇)、反应温度、反应时间对螯合反应的影响,最优反应条件为:V(水)∶V(乙醇)=1∶4,40℃,6 h。采用红外光谱,紫外光谱和差热-热重分析对寡聚酸合铜(Ⅱ)配合物进行了表征。红外光谱和紫外光谱分析均表明,Cu2+与寡聚酸配位。寡聚酸合铜(Ⅱ)配合物中金属配位方式为单齿配位。热分析表明,配合物在190℃之前是稳定的,其分解过程是逐步进行的。初步应用实验表明,叶面喷施稀释100 000倍的寡聚酸合铜(Ⅱ)促进了花生的生长发育。     

月桂酸酯季铵盐阳离子表面活性剂的合成与表征

以十二烷基二甲基叔胺、环氧氯丙烷为原料,合成了中间体DMAC〔(2,3-环氧丙基)十二烷基二甲基氯化铵〕,再与月桂酸反应,生成月桂酸酯季铵盐阳离子表面活性剂HDAC〔(2-羟基-3-月桂酰氧基丙基)十二烷基二甲基氯化铵〕。通过正交实验确定了最佳合成条件:以异丙醇为溶剂,n(DMAC)∶n(LAC)=1∶1.2,反应时间6 h,反应温度50℃,产率大于90%,Krafft点-4.52℃。通过元素分析、傅立叶变换红外光谱、飞行时间质谱(TOF-MS)、1HNMR,确证了目的产物的结构。测定产物的临界胶束浓度CMC为8.91×10-4mol/L,γCMC为34.12 mN/m。表明所合成的月桂酸酯季铵盐阳离子表面活性剂具有较高的表面活性。     

Separation,Purification and Characterization of Three Endo-polygalacturonases from a Newly Isolated Penicillum oxalicum

Three endo-polygalacturonases (endoPGs) from a newly isolated Penicillum oxalicum (CGMCC 0907) capable of utilizing waste biomass as growth substrate were separated and purified to homogeneity by ultra-filtration, affinity adsorption chromatography, CM-cellulose column chromatography, and Sephadex G-100 gel filtration chromatography with the overall yield of 64.5% from the crude enzyme. The specific activities and recovery rates of endoPG-1, endoPG-2 and endoPG-3 were 1120 U/mg and 21.6%, 1350 U/mg and 25.9%, and 1560 U/mg and 17.0%, respectively. The three purified endoPGs had a close molecular weight to 41 kDa as estimated by SDS-PAGE. The optimum temperature and pH for the function of them were 65℃ and 5.0, 55℃ and 5.0, 50℃ and 5.5, respectively. Their pI and Km values were 5.9 and 0.78 mg/mL, 6.0 and 1.2 mg/mL, and 6.1 and 2.0 mg/mL, respectively.     

Methods to Investigate the Adhesion of Soft Nano‐Coatings on Metal Substrates – Application to Polymer‐Coated Stents

Soft coatings are widely used to tailor the surface chemistry of materials without altering their bulk properties. However, the strength of adhesion between the coating and the substrate must be high enough for long‐term applications. This has become a major challenge in the medical field, especially for polymer‐coated stents, mainly due to several coating failures reported after mechanical expansion during clinical implantation. In this work, the applicability of current polymer‐metal adhesion tests to polymer‐coated stents is discussed. The small punch test was proposed as an adhesion test that allows fundamental studies on the adhesion and coating properties. This adhesion test was applied to thin fluorocarbon coatings deposited by plasma on 316L stainless steel.

     

Synthesis of hyperbranched organo‐montmorillonite and its application into high‐temperature vulcanizated silicone rubber systems

N,N‐Di(2‐hydroxyethyl)‐N‐dodecyl‐N‐methyl ammonium chloride was used as intercalation agent to treat Na⁺‐montmorillonite and form a type of organic montmorillonite (OMMT). Hyperbranched OMMT (HOMMT) was prepared by condensation reaction between OMMT and the monomer we synthesized. It was then used in the preparation of high‐temperature vulcanizated silicone rubber (HTV‐SR)/HOMMT nanocomposite. Different types of HTV‐SR/HOMMT nanocomposites were prepared with different amounts of HOMMT and compared with the composites directly incorporated with OMMT. Tensile properties such as tensile strength, elongation at break, permanent distortion, and shore A hardness were researched and compared. A combination of Fourier transform infrared spectroscopy, wide angle X‐ray diffraction, and transmission electron microscopy studies showed that HTV‐SR/HOMMT composites were on the nanometer scale, and the structure of HTV‐SR was not interfered by the presence of HOMMT. Results showed that the tensile properties of HTV‐SR/HOMMT systems were better than that of the HTV‐SR/HOMMT and HTV‐SR. This was probably due to the surface effect of the exfoliated silicate layers and anchor effect of HOMMT in the SR matrix. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

偕二硝基乙酸乙酯的合成与表征

以丙二酸二乙酯为起始原料,经水解、脱羧氧化硝化得到标题化合物,并利用红外光谱、核磁共振、质谱等鉴定其结构;初步探讨了脱羧氧化硝化反应历程,优化了反应条件;对二硝基乙酸乙酯合成方法进行了重大改进,发现以NaNO2-98%工业硝酸为硝化剂,具有原料易得、操作简便、收率较高(>65%)、粗品纯度较高(>93%)的优点.     

含杂环基团的1,2,4-三唑衍生物的合成及其结构表征

利用芳酰肼与异硫氰酸苯酯为原料,合成了中间体1,4-二取代氨基硫脲,进一步在碱体系中缩合得到含杂环3,4-二取代-5-巯基-1,2,4-三唑.通过IR、1HNMR、13CNMR、MS及元素分析等测定对产物的结构进行了表征.     

乙二胺四乙酸铁钠的固液相反应制备工艺

采用固液相法制得乙二胺四乙酸铁钠,并用XRD、IR、DTA等对产物进行了表征,X射线粉末衍射数据指标化结果表明所合成的配合物属于单斜晶系,晶胞参数为:a=1.4388 nm,b=1.3521 nm,c=1.3311 nm,β=100.90°。同时确定了合成反应的较佳条件:n(EDTA)∶n[Fe(OH)3]=1∶1,pH=5,反应温度80°C,反应时间60 min,产率68.4%。     

Synthesis and characterization of cobalt nano‐particles through microwave polyol process

This article aims to synthesize and character cobalt nano‐particles through microwave polyol process. At first, cobalt acetate is used as precursor to synthesize cobalt nano‐particles by microwave assisted ethylene glycol in the presence of polyvinylpyrrolidone (PVP) as capping agent. As measured from ion‐coupled plasma (ICP) and thermo‐gravimetric analysis (TGA), the yields of as‐synthesized cobalt particles in average diameters of 40 and 81 nm verified by transmission electronic microscopy (TEM), are 71 and 85%, respectively; and the structure of as‐synthesized cobalt nano‐particle is a face‐center cubic structure analyzed by X‐ray diffraction (XRD). Finally, the as‐synthesized cobalt nano‐particle modified by oleic acid is dispersed in kerosene to character magnetic property. As measured by vibration sample magnetometer (VSM), the saturation magnetisms of cobalt nano‐particles with average diameters of 40 and 81 nm are 39.1 and 29.5 emu/g, respectively, in solution. © 2009 American Institute of Chemical Engineers AIChE J, 2009     

Modeling of coupled mass and heat transfer through venting membranes for automotive applications

Experimental and theoretical approaches based on a mathematical model, have been developed to study the evolution of environmental parameters (temperature, total pressure, relative humidity, and water vapor partial pressure) inside a housing of an electronic device with a window containing a macroporous membrane. The model was based on the coupling of mass and heat transfer taking into account the effects of polarization of concentration in boundary layers. Membranes have been characterized by mercury porosimetry, liquid entry pressure measurements, scanning electron microscopy, and gas permeation. Once the model was experimentally validated, it was applied to investigate the influence of membranes on heat and mass transfer and to study the impact of the boundary layers on the global mass transport. The results demonstrated the importance of the membrane choice and dimensions to get the best temperature regulation and avoid water condensation inside an automotive electronic control unit (ECU). © 2008 American Institute of Chemical Engineers AIChE J, 2009