燃烧法合成高纯度负热膨胀材料ZrW2O8粉体

采用燃烧法在较低温度下成功合成了各向同性的负热膨胀材料ZrW2O8粉体.用X射线衍射、扫描电镜、红外光谱综合分析和研究了反应过程中炉温、硼酸和尿素含量、W6 与Zr4 的摩尔比对合成ZrW2O8纯度的影响.结果表明:燃烧法可以合成高纯度、粒径为0.5μm的ZrW2O8粉体.燃烧法合成高纯ZrW2O8的最佳条件是:炉温为500℃,硼酸的摩尔分数为10%,(NH2)2CO与(NH4)5H5[H2(WO4)6]·H2O ZrOCl2·8H2O的质量比为2∶1,(NH4)5H5[H2(WO4)6]·H2O与ZrOCl2·8H2O的摩尔比为1∶3.2.所合成的ZrW2O8在50～700℃之间的线膨胀系数a=-5.08×10-6/℃,其线膨胀系数与温度的关系符合方程dL/L0=-1.4×10-2-4.5×10-4T(50℃≤T≤700℃).     

Reformatsky试剂及其反应在制药上的新应用

Reformatsky试剂是应用较多的精细有机合成试剂之一.由于用该试剂比较容易进行Reformatsky反应,可合成强效镇痛药"依那朵林"的中间体4-苯并呋喃乙酸,以及具有强心作用的"强心甾"等医药,也可合成很有应用价值的药物萜类化合物"甲瓦龙酸内酯"等.     

直接甲醇燃料电池阳极催化剂的制备

直接甲醇燃料电池（DMFC）阳极催化剂是DMFC的关键材料之一,其电化学活性的大小对燃料电池的输出性能及成本起着关键作用。不同催化剂的制备技术决定了催化剂电化学活性的高低。介绍了DMFC阳极催化剂的几种制备方法,并对这些方法进行了评述,对制备DMFC阳极催化剂具有很好的参考价值。     

ABO3钙钛矿型复合氧化物光催化剂设计评述

评述了ABO₃钙钛矿型光催化剂设计的5项原则：（1）能带结构的选择和调控;（2）主要决定光催化剂活性的B位元素的选择;（3）A位元素的选择;（4）由A位和/或B位的部分替代可实现化合价和空位控制,极大地提高光催化活性;（5）形成超细粒子或分散在载体上引起表面积增大,有利于光催化活性的提高。     

Experimental Study of Plasma Under-liquid Electrolysis in Hydrogen Generation

The application and characteristics of relatively big volume plasma produced with cathodic glow discharges taking place across a gaseous envelope over the cathode which was dipped into electrolyte in hydrogen generation were studied. A critical investigation of the influence of methanol concentration and voltage across the circuit on the composition and power consumption per cubic meter of cathode liberating gas was carried out. The course of plasma under-liquid electrolysis has the typical characteristics of glow discharge electrolysis. The cathode liberating gas was in substantial excess of the Faraday law value. When the voltage across the circuit was equal to 550 V, the volume of cathodic gas with sodium carbonate solution was equal to 16.97 times the Faraday law value. The study showed that methanol molecules are more active than water molecules. The methanol molecules were decomposed at the plasma-catholyte interface by the radicals coming out the plasma mantle. Energy consumption per cubic meter of cathodic gases (WV) decreased while methanol concentration of the electrolytes increased. When methanol concentration equaled 5% (j), WV was 10.381′103 kJ/m3, less than the corresponding theoretic value of conventional water electrolysis method. The cathodic liberating gas was a mixture of hydrogen, carbon dioxide and carbon monoxide with over 95% hydrogen, if methanol concentration was more than 15% (j). The present research work revealed an innovative application of glow discharge and a new highly efficient hydrogen generation method, which depleted less resource and energy than normal electrolysis and is environmentally friendly.     

新型离子液体气相色谱固定相研究

合成了一种用作新型气相色谱固定相的室温离子液体[C7H17NO] [(CF3SO2)2N]-,并考察其色谱性能。该固定相具有较好的成膜性、较高的柱效、较强的极性,对正构烷烃、芳香族化合物以及一些位置异构体具有良好的分离效果。     

纳米TiO2粉体晶相组成定量分析计算方法

通过理论计算,给出了纳米TiO2混晶中金红石相和锐钛矿相相对含量的计算公式,与文献中实验方法得出的计算公式吻合,理论计算和实验结果得以很好的相互验证。     

不同氧化剂制备可膨胀石墨的研究

通过混酸法制备了两种不同氧化剂体系的可膨胀石墨(EG),并采用膨胀容积和X射线(XRD)对EG进行了表征。实验结果表明:K2Cr2O7为氧化剂制备的可膨胀石墨,氧化充分,插层效果好,膨胀容积(EC)大,K2Cr2O7同石墨的最佳比例是0.8∶10。     

二乙二醇甲乙醚的合成及其合成条件优化

以二乙二醇单乙醚(DEGME)和氯甲烷为基本原料,氢氧化钠为催化剂、苯为带水剂,通过Williamson反应合成了二乙二醇甲乙醇(DEGMEE);用正效实验法对DEGMEE的合成条件进行了优化,气相色谱法分析了产品中DEGMEE的含量、FT IR和1H NMR法表征了产物结构。实验结果表明适宜的反应条件为:反应温度为60.0°C、醚化时间为4.0 h、n(CHCl)/n(DEGME)=1.15、n(NaOH)∶(DEGME)=1.30;在此条件下二乙二醇甲乙醚的收率可达93%以上。     

氨基乙酸衍生二苯并-18-冠-6的合成研究

采取两种不同的方法,即分别以氨基乙酸和二溴二苯并-18-冠-6(摩尔比为2∶1)或者以氯乙酸和二氨基二苯并-18-冠-6(摩尔比为2∶1)为原料,在回流温度下,合成氨基乙酸衍生二苯并-18-冠-6,其中用二氨基二苯并-18-冠-6和氯乙酸作用下,回流7 h产率较高,可达80%。目标化合物由红外、核磁共振及元素分析等手段进行表征。