铜在硝酸介质苯并三唑抛光液中化学-机械抛光时的电化学行为

用电化学测试技术研究了硝酸、苯并三唑及H2O2浓度对铜表面的成膜及铜抛光过程的影响.测试了各种体系中铜的交流阻抗及其影响因素，探讨了腐蚀电流密度与抛光压力、抛光转速的关系，考察了化学-机械抛光过程中腐蚀电位及极化曲线的变化规律. 用腐蚀电流密度及腐蚀电位等电化学变量的变化解释了抛光过程的电化学机理，证明在硝酸溶液介质中，以苯并三唑为成膜剂、H2O2为助剂、纳米g -Al2O3为磨粒的抛光液配方是可行的.     

丙烯酸系有机亲水涂料制备研究

亲水涂料主要用于空调热交换器翅片表面,以提高其亲水性、耐蚀性等。本文采用丙烯酸(AA)/丙烯酰胺(AM)水溶液共聚法制备高亲水树脂,同时对交联剂及涂料的pH值对涂膜的影响进行了研究。     

La_(1-x)Ce_xMnO_3微波吸收特性

用溶胶-凝胶法制备了La1-xCexMnO3(x=0.1,0.2,0.3,0.4,0.5)样品,用微波矢量网络分析仪测试了该样品在2～18 GHz微波频率范围的复介电常数、复磁导率,根据测量数据计算了电磁损耗角正切及微波反射率与频率的关系.结果表明,在x=0.4时,样品微波吸收效果最好.当样品厚度为2.20 mm、x=0.4时,吸收峰值为27 dB,10 dB以上频带宽度达3.2 GHz.初步探讨了该材料的电磁损耗机理,发现损耗吸收来自磁损耗和介电损耗的共同作用,吸收峰所在频率介于介电损耗角正切最大值与磁损耗角正切最大值对应的频率之间,即在13.2 GHz附近.对样品的电阻率测试表明,其室温范围内电导在半导体范围内,有利于降低微波在样品表面的反射率.     

Electrochemical behavior of diverse vanadium ions at modified graphite felt electrode in sulphuric solution

PAN-based graphite felt (PGF) treated in 98% sulphuric acid for 5 h and then kept at 450 ℃ for 2 h was evaluated for their electrochemical performance as electrodes of vanadium redox battery (VRB). Structure and characteristic of treated PAN-based graphite felt (TPGF) were determined by means of Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy, Brunauer-Emmett-Teller surface area analysis and VRB test system. The results show that the acid and heat synergistic effect increase the number of —COOH functional groups on the PGF surface, and the PGF is eroded by sulphuric acid oxidation, resulting in the surface area increases from 0.31 m2/g to 0.45 m2/g. The V(Ⅱ)/V(Ⅲ) redox reaction is electrochemically reversible on the TPGF electrode, while the V(Ⅳ)/V(Ⅴ) couple is a quasi reversible process. The diffusion coefficients of the oxidation for V(Ⅳ)/V(Ⅴ) obtained from the scope of peak current Ip vs scan rate v1/2 is 4.4×10-5 cm2/s. The improvement of electrochemical activity for the electrode is mainly ascribed to the increase of the number of —COOH groups on the TPGF, which behaves as active sites catalyzing the vanadium species reactions and accelerating electron transfer reaction and oxygen transfer.     

Syntheses and cofluorescence of complexes of Eu（Ⅲ）/Y（Ⅲ） with terephthalic acid, 2-thenoyltrifluoroacetone and trioctylphosphine oxide

A series of Eu（ Ⅲ）/Y（Ⅲ） complexes of terephthalic acid（TPA） with 2-thenoyltrifluoroacetone（HTTA） and trioctylphosphine oxide（TPPO） were synthesized. Compositions of these complexes are revealed to be Eu2（1-x）Y2x（TPA）（TTA）4- （TPPO）4 or EU1-xYx（TPA）（TTA）（TPPO）2. Their 1R spectra, fluorescent spectra and the thermal and optical stability were studied. The fluorescent excitation spectra of these complexes show more broad excitation bands than those of Eu2（TPA）3（TPPO）4 and Eu（TTA）3（TPPO）2 corresponding to their formations. In addition, both the binuclear complex EuY（TPA）（TTA）4（TPPO）4 and the chain complex EU0.4Y0.6（TPA）（TTA）（TPPO）2 present higher thermal stability and better optical stability than the mononuclear complex Eu（TTA）3（TPPO）2 does. And their thermal and optical stabilities are preferably interpreted from the binuclear structure together with the chain polynuclear structure of the complexes. The fluorescence enhancement of cofluorescence Y^3＋ ions to the Eu（Ⅲ） complexes is clear. The optimum content of Y^3＋ is 0.6 （molar fraction） for the chain complexes Eu1-xYx（TPA）（TTA）- （TPPO）2 and 0.5 for the binuclear complexes Eu^2（1-x）Y2x（TPA）（TTA）4（TPPO）4. The formation of polynuclear structure of the complex Eu1-xYx（TPA）（TTA）（TPPO）2 appears to be responsible for the good cofluorescence effect of Y^3＋ ions.     

椎弓根钉固定结合骨屑填充伤椎治疗胸腰椎骨折

目的探讨椎弓根钉复位固定结合骨屑填充伤椎成形治疗胸腰椎骨折的方法和疗效。方法 2008年1月至2009年12月对34例胸腰椎骨折采用椎弓根钉复位固定后自体骨屑填充伤椎的方法治疗,术后随访并评估此方法的临床疗效。结果随访6～20个月,34例患者均未出现明显椎体高度再度丢失,无一例发生内固定断裂、松动。结论椎弓根钉复位固定后采用自体骨屑填充植骨,可减少椎体高度再丢失及内固定断裂、松动等并发症。     

MSnO3(M=Ca,Sr,Ba)的溶胶-凝胶法合成及性能

采用溶胶-凝胶法制备了钙钛矿结构的MSnO3(M=Ca,Sr,Ba)晶体.将其作为锂离子电池负极材料的活性物质,利用恒电流电池测试仪研究其电化学性能.结果表明CaSnO3、SrSnO3和BaSnO3的首次放电容量分别为894.3 mAh/g、703.8 mAh/g和673.6 mAh/g,首次充电容量分别为418.3 mAh/g、257.8 mAh/g和224.8 mAh/g,不可逆容量损失分别达53.2%、63.3%和66.6%.     

手性配体交换乳状液膜选择性萃取扁桃酸对映体

基于手性配体交换反应,研究了在含有N-n-十二烷基-L-羟基脯氨酸和铜离子的配合物为手性配体的乳状液膜体系中选择性萃取扁桃酸对映体.考察了扁桃酸外消旋体浓度,手性萃取方向,有机溶剂和表面活性剂配比,从外水相到内水相pH值的梯度变化以及外水相的pH值变化对选择性萃取性能的影响,从而确定了合适的选择性萃取条件.     

纸泥/环氧酚醛树脂复合物与环氧酚醛树脂的阻燃性研究

将含各类阻燃剂加入到环氧酚醛树脂和纸泥/环氧酚醛聚合物中,用UL-94等级燃烧测试法测定体系的燃烧等级,结果表明:TCEP和无机阻燃剂对环氧酚醛树脂有阻燃作用,但卤化和磷酸化的阻燃剂能增强纸浆/环氧酚醛复合材料的阻燃性.用热重分析仪和差示扫描量热仪对复合材料进行热分析研究阻燃机理,结果显示环氧酚醛树脂材料和纸泥/环氧酚醛复合材料的阻燃性取决于本身的热容和热分解行为.     

pH值对水热法制备ZnGa2O4粉体的影响

采用水热法制备了ZnGa2O4纳米粉体,使用XRD、SEM、TEM及AFM对不同pH值条件下产物的结构及微观形貌进行了表征.结果表明pH值调节严重影响ZnGa2O4的晶相及粒度:当pH≥7.5时,可得到纯相的ZnGa2O4纳米粉体;随着pH的增加,晶胞参数增加,所得样品的平均粒径不断减小,其粒径范围为6～11nm,发射峰位置在450nm左右.所得样品的晶型很完整,GaO(OH)为细长棒状,ZnGa2O4晶粒为四方形和圆形.