含硼片状锌热固涂层耐蚀性与结构的研究

片状锌热固涂层作为一项清洁生产的高新技术 ,一次完成多层涂覆和钝化 ,具有高抗蚀、无废水排放、无氢脆、高耐热和涂层薄 (一般小于1 0 μｍ)等显著优点 ,在应用前景上具有取代电镀锌的趋势[1] 。在盐水溶液中 ,这种涂层的耐蚀性最高可达电镀锌的 1 0倍 ,但在淡水中却不具有这样的优势。我们用硼酸部分取代铬酸配制涂层处理液 ,明显改善了涂层在淡水中的耐蚀性。为解释硼酸的作用机理 ,采用Ｘ 射线衍射 (ＸＲＤ)、Ｘ 射线光电子能谱 (ＸＰＳ)和核磁共振 (ＮＭＲ)等测试手段对膜层的结构进行了研究。1　实验部分1 1　仪器与药品ＨＤＶ 7Ｂ…     

UV cured transparent films including non‐aqueous conductive microgels

UV cured transparent films containing non‐aqueous conductive microgels coated with poly(aniline)/dodecyl benzenesulfonic acid(DBSA) were obtained. The conductive microgels were prepared by interface polymerization of aniline/DBSA in the presence of non‐aqueous polymeric microgels. The electrical conductivity and the particle size of the prepared conductive microgel were 0.5 S/cm and 58 nm, respectively. The prepared conductive microgels were easily blended with a UV curable coating formulation, and then were cured to make highly optically transparent films. For the UV cured film containing about 35 wt% of the conductive microgels, a surface resistance in the range of 10⁷ to 10⁸ Ω/square was obtained. In a polar cosolvent, such as NMP and m‐cresol, the critical volume was shifted to the lower range, with a value of 10 wt%. The UV cured films containing the conductive microgels exhibited good electrical stability against the thermal aging and humidity. Copyright © 2002 John Wiley & Sons, Ltd.     

VPO催化剂上丙烷选择氧化反应机理的分子探针研究

ＶＰＯ催化剂上丙烷选择氧化反应机理的分子探针研究赵如松，徐铸德（浙江大学化学系，杭州３１００２７）关键词ＶＰＯ催化剂，丙烷，选择氧化，分子探针，反应机理最近研究［１－２］表明，Ｃ３０在ＶＰＯ催化剂上可直接选择氧化成丙烯酸和乙酸。这种工艺与现行烯烃为原...     

螯合树脂研究——Ⅷ.以聚硫醚为主链的氧杂多乙烯多胺型螯合树脂的合成及其吸附性能

由聚[2′-氯乙基-2,3-环硫丙基醚]和多乙烯声胺反应,合成了四种以聚硫醚为主链的氧杂多乙烯多胺型螯合树脂,它们对贵金属离子Au(Ⅲ)、Pd(Ⅱ)、Pt(Ⅳ)、Ag~+等具有优良的吸附性能。     

An Efficient Route to Emodic Amine and Analogous <Emphasis Type="Italic">O</Emphasis>-Methyl Protected Derivatives Starting from Emodin

Summary. Emodic amine could be synthesized in a five-step approach in excellent overall yield by following a modified Curtius rearrangement strategy, starting from the naturally occurring emodin. This unique emodin derived 6-amino substituted polyhydroxylated anthraquinone may serve as a promising synthon for a new class of amino functionalized photodynamically active hypericin derivatives. In addition, the partially O-methyl protected 6-amino- and 6-carboxy-anthraquinones could be synthesized in high yields via selective O-methyl ether cleavage from the corresponding tri-O-methyl derivatives.     

Hydroxyapatite/Metal Composite Coatings Prepared by Two-step Electrodeposition Method

Threewidelyused0rth0pedicanddentalimPlantmaterialsarestainlesssteel,Co-Cr-MoalloysandTi-Al-Valloys.Inrecentyears,researchinthisfieldhasbeenorielltedt0wardcoatingthesemetaltwlanmaterialswithbiocomPatibleandbi0activehydroxyaPatite(HAP)toreduceimPlanfailuresduetoisolationandtoobtaincementlessfixationoftheirnPlant.Currently,themostwidelyaPPliedcoatingprocedureistheplasmaspraytechnique."'Themajorproblemfortheplasmaspray,however,isdecomPositionandphasetransformation0fhydroxyapatiteduringthesp…     

Selective Method for the Conversion of Oximes to Their Corresponding Carbonyl Compounds under Microwave Irradiation by N‐Bromo‐N‐Phenyl‐Para‐Toluenesulfonamide

In this work, oximes are converted to their corresponding carbonyl compounds in good yields using N‐bromo‐N‐phenyl‐para‐toluenesulfonamide, under microwave irradiation. The simple work‐up procedure minimizes loss of product.     

Method development and validation for the simultaneous determination of five selective serotonin reuptake inhibitors by capillary zone electrophoresis

Summary A capillary zone electrophoresis method is proposed for the separation of five antidepressants. Optimum conditions for the separation were investigated. A background electrolyte solution consisting of 40 mM phosphate buffer adjusted to pH 2.5, hydrodynamic injection, and a 28 kV separation voltage were used. Relative standard deviations (RSD) were <0.9% and <1.7% for migration time and corrected peak area (n=21), respectively. The detection limits for the five antidepressants ranged from 0.3 to 0.7 mg L⁻¹. The stability of the solutions, linearity, accuracy, and precision were examined during validation of the method. The method is rapid and sensitive, when it was tested for the analysis of pharmaceutical formulations the recoveries obtained were between 98 and 103% of the nominal content.     

Thin-film TiO2 electrode surface characterization upon CO2 reduction processes

The effect of electrochemical reduction of CO₂ on the structure and morphology of titanium(IV) oxide thin films was examined after a fixed-potential bulk electrolysis process. Films deposited on ITO (Indium-Tin Oxide) substrates were used as the working electrodes and 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIm][BF₄]) as solvent and as supporting electrolyte. Grazing incidence X-ray diffraction analysis performed before and after the electrolysis process indicated no microstructural changes of the anatase films. X-ray photoelectron spectroscopy revealed peaks associated with adsorbed carbonate ions at 288 eV and CO₂ species at 293 eV, whereas Ti2p peaks displacements for CO₂-saturated TiO₂/ITO surfaces in [BMIm][BF₄] revealed chemical bonding effects. Auger electron spectroscopy revealed a high carbon content on CO₂-exposed films, and suggested a strong chemisorption of CO₂ and CO₃²⁻ species on the TiO₂/ITO surface in [BMIm][BF₄] solvent system. A significant decrease in carbon content after bulk electrolysis indicated that the CO₂ electroreduction process is not controlled by either diffusion or by adsorption of CO₂ on the TiO₂/ITO electrode surface.     

LiMn2O4表面包覆Li4Ti5O12的制备及倍率特性

采用固相法合成了尖晶石型LiMn₂O₄，并通过溶胶-凝胶法制备了不同物质的量的百分比含量Li₄Ti₅O₁₂包覆的正极材料。X-射线衍射和扫描电镜结果表明，Li₄Ti₅O₁₂微粒包覆在LiMn₂O₄的表面没有产生晶体结构的变化。实验电池在室温下，以1C，2C和5C倍率作充放电循环测试；结果表明，与未包覆的LiMn₂O₄相比，表面包覆Li₄Ti₅O₁₂微粒的正极材料在高倍率下具有更好的循环稳定性。