ZrO2添加量对ZTA陶瓷力学性能及冲蚀磨损行为的影响

以α-Al2O3、ZrO(NO3)2.2H2O和氨水为原料,通过高温煅烧制备了ZTA复相陶瓷材料,研究了ZrO2添加量对ZTA陶瓷物相组成、表面微观形貌、力学性能以及常温固体粒子冲蚀磨损性能的影响。结果表明:随着ZrO2添加量增加,材料的力学性能逐渐提高,当ZrO2添加量为10 vol%时,ZTA复相陶瓷抗弯强度和断裂韧性分别达461MPa和5.77 MPa.m1/2,相对于纯Al2O3陶瓷提升量达21.3%和64.9%。ZTA复相陶瓷材料的体积冲蚀率随着ZrO2添加量的增加而降低,当ZrO2添加量小于4 vol%时,其体积磨损率急剧下降,随后趋于平稳;随后当ZrO2添加量为10 vol%时,其冲蚀率达最低,为0.015 mm3/g。其中,纯Al2O3陶瓷材料的冲蚀磨损机制主要为横向裂纹相互交错导致材料的剥落,添加ZrO2后,其冲蚀磨损机制以塑性变形为主。     

Design,Syntheses and Biological Activities of Novel Sulfonylureas Containing an Oxime Ether Moiety

Since sulfonylurea is one of the most potent acetohydroxyacid synthase(AHAS) inhibitors, a series of novel sulfonylureas containing an oxime ether moiety was designed and synthesized and their chemical structures were determined by means of ¹H nuclear magnetic resonance(NMR), ¹³C NMR and high-resolution mass spectrometry(HRMS). In the herbicidal bioassay, several compounds showed moderate to good herbicidal activities against dicotyledons, but their activities against monocotyledons decreased. The in vitro antifungal activity was tested at a dosage of 50 mg/L. And the results show that compounds 7l, 7m and 7n exhibit promising antifungal activities against six common plant pathogenic fungi. Further investigations on molecular modification are in progress.     

熔盐法包覆BaTiO_3及其电性能

通过熔盐法将MgTiO3薄膜均匀地包覆在钛酸钡颗粒表面形成芯壳结构。包覆机理是在MgCl2的熔盐状态800℃下Mg2 取代BaTiO3中的Ba2 离子表面生成MgTiO3薄膜薄膜厚度约20nm。采用TEM、XRD验证了MgTiO3的包覆。包覆粉末经烧成瓷后具有良好的高频性能在1MHz～800MHz的频率范围内介电常数恒定为130。     

Effect of Rotation Rate on the Formation of Platinum-modified Polyaniline Film and Electrocatalytic Oxidation of Methanol

The oxidation of methanol was investigated on platinum-modified polyaniline electrode.Changes in the electrode rotation rates (Ω) during platinum electrodeposition remarkably affect the formation and distribution of platinum in the polymer matrix and consequently lead to different currents of methanol oxidation. The results show that platinum loading is proportional to rotation rates Ω^1/2.     

水热法合成SnO2金红相纳米柱和亚微米晶体

本文采用水热法,以SnCl4·5H2O为前驱物,在180℃,填充度为68;,反应时间8h,强酸环境条件下合成了SnO2纳米金红相晶体,直径约为5～10nm,长30～100nm.加入一定量的NaOH,调节溶液pH值为强碱性(pH=11),同样条件下也合成了SnO2金红相纳米柱晶体,长200nm、直径10～20nm.提高水热反应的温度为430℃,矿化剂为3mol/L NaOH,反应时间24h,合成了亚微米金红相SnO2晶体,最大线度为300nm.     

关于证明电离平衡实验方案的商榷

由人民教育出版社化学室编著,2003年出版的全日制普通高级中学教科书(必修加选修)《化学》第三册·第六单元·第一y·性质实验方案的设计习题中,有这样一道习题:设计实验,证明弱电解质的电离平衡是客观存在的.(提示:可用冰醋酸、电流表、蒸馏水等).《教师教学用书》中,对该题的参考答案是这样的:在SOOxnL或1000mL的烧杯中,加入少量的冰醋酸,刚好使电极浸没为IF,用电极导线连接电流表、接通电源,观察电流表指针摆动的情况.然后用蒸馏水逐滴地进行稀释,边加蒸馏水边振荡或用玻璃棒搅动.在稀释前指针不动,随着稀释电流表指针摆动越来越大.如果不断稀释,电流表指针摆动又会逐渐减少.由此,就证明弱电解质的电离平衡是客观存在的.笔者并不完全认同,提出以下观点与同仁共同商讨.     

CdWO4纳米晶形貌可控合成

分别以氯化镉、草酸镉、碳酸镉、柠檬酸镉和钨酸钠为原料,在没有采用模板和表面活性剂的条件下,采用水热法可控制备出了钨酸镉纳米颗粒、纳米棒、纳米束和纳米线.利用X射线衍射(XRD)、透射电镜(TEM)、高分辨透射电子显微镜(HRTEM)和选区电子衍射(SAED)对样品进行了表征.结果表明:[WO42-]/[Cd2+]摩尔比、反应时间及先驱体的类型对产物的形貌和尺寸有着重要的影响.     

三组分体系相图教学实验——微乳的制备*

为了让三组分体系相图的教学紧跟学科发展前沿,设计了一个研究型综合性实验——微乳的制备。实验以油酸乙酯为油相、吐温-80和乙醇质量比为3∶1的混合体系为乳化剂相,蒸馏水为水相,采用水滴定和油滴定结合的方法绘制了拟三元相图。通过电导率法对微乳3种类型的转变点进行了初判,按照电导率实验结果制备了3种不同类型的微乳样品,并利用染色法、黏度法和光散射法对微乳的物理化学性状进行了表征。通过实验,可以使学生获得分散体系的前沿知识,有利于创新人才的培养。     

牛血清白蛋白与甲基橙结合反应的研究

用分光光度法研究了牛血清白蛋白与甲基登在酸性溶液中的结合反应，认为两者通过非共价键结合，研究了溶液吸光 度与组分浓度的关系，对Ｓｃａｔｃｈａｒｄ模型用于自理蛋白质染色反应时存在的总是作了讨论，提出了表观结合常数的概念，推导了求算表观结合常数和最大结合数的线性回归公式。     

Investigation of voltammetric enzyme-linked immunoassay based on new system of ODA-H_2O_2-HRP

A voltammetric enzyme-linked immunoassay based on a new system of ODA-H2O2-HRP has first been developed and used in the detection of HRP and labelled HRP. By this method, the enzyme-catalyzing reaction of H2O2 oxidizing odianisidine (ODA) couples the electrode-reduction reaction of the oxidizing product of odianisidine, which produces a sensitive polarographic wave at potential of -0.56V (SCE) in Britton-Robinson buffer solution. In using this polarographic wave, a detection limit to HRP is 3.7×10-12g/mL and a linear range 1.0×10-11-2.0×10-9g/mL. And the mechanisms of the coupling reaction and the process of electro-reduction in the ODA-H2O2-HRP voltammetric enzyme-linked immunoassay system have also been carefully studied.