酞菁裂解法多壁碳纳米管的制备、表征和应用

In order to investigate the catalytic activity of high temperature treated CoPc toward oxygen reduction, and find the active site of the catalyst, using cobalt (Ⅱ) phthalocyanine (CoPc) as raw material, through thermal chemical vapor deposition method at 850℃ under a current of Ar/H2, two layer well-aligned multiwalled carbon nanotubes (CNTs) were made. The diameters of the well-aligned carbon nanotubes were distributed in the range of 60～120 nm and the length was about 40 μm. The Co particle with 10 nm in diameter was encapsulated in the CNTs compartment. The products were observed by field emission scanning electron microscope (SEM), and transmission electron microscope (TEM). The well-aligned carbon nanotubes were characteriszed by Raman scattering spectrum and X-ray diffraction (XRD). The cyclic voltammetric measurement demonstrates that the CNTs have some effect to prevent the metal nanoparticle encapsulated from eroding rapidly. It is assumed that the small amount of the N element in the CNTs is very necessary for the bamboo-like morphology and the protected action for metal particles against dissolution in the acid medium. The radian of the winding wall should be affected by the amount of the N and the interaction between the N in the carbon network and the metal cluster. In addition, the CNTs greater electrochemically active surface area is a great advantage for any electrocatalytic application.     

An expeditious and one-pot synthesis of unsymmetrical 2,5-disubstituted-1,3,4-oxadiazoles under microwave irradiation and solvent-free conditions

A one-pot synthesis of some unsymmetrical 2,5-disubstituted-1,3,4-oxadiazoles via cyclocondensation of benzoylhydrazines with orthoesters under solvent-free and microwave conditions are described here. The reaction is efficiently catalyzed by silica- supported sulfuric acid as it provided the title compounds in high yields and relatively short times. The catalyst is reusable and can be applied several times without considerable decrease in the yields and rates of the reactions.     

原子荧光光谱技术在我国发展及标准化应用现状

简单介绍了原子荧光光谱技术的建立及其在国内的发展历程,重点介绍了蒸气发生-原子荧光光谱(VG-AFS)仪在我国的技术研究、仪器研制及应用;详细总结了蒸气发生-原子荧光光谱(VG-AFS)法在我国标准化方面的研究.我国在多通道原子荧光光谱仪、原子荧光形态分析仪等关键技术及其应用等方面取得了开创性的研究成果,并形成了一系列...     

磁控溅射锆钒合金膜

蒸发成膜合金中的各成分蒸发速率为GA=7．714XAPA（MA／T）^1/2，G4为合金中A成分的蒸发速率，g／cm^2．s；局为合金中A成分的摩尔分数；n为4物质的纯蒸气压，Pa；心为4物质的分子量；T为温度，K。     

L-乳醛的合成及Wittig反应立体选择性

L-乳醛以由L-乳酸甲酯经过一步硅保护，然后用二异丙基氢化铝溶液（DIBA1-H）还原制备得到．立体选择性化合物的制备是当代有机合成化学中非常重要而且具有挑战性的领域之一．高度立体选择性的各类化合物，包括立体高度选择性的烯烃化合物正在越来越频繁的运用在合成当中．本文系统地研究了L-乳醛与一系列不同类型的叶立德试剂在不同条件（改变温度、溶剂、碱）下发生Wittig反应的立体选择性，总结了一些基本规律，为今后得到立体专一的烯烃打下基础．     

S-两基O-苯基N-烷基硫赶磷酰胺酯的研究(Ⅴ)——丙硫基磷酰化合物的合成

含正丙硫基硫代磷酸酯类农药不同于以往的有机磷杀虫剂,其特点是杀虫活性或杀螨活性一般较高,但对温血动物的毒性却较低,并且对含磷农药业已产生抗性的害虫有特效。研究表明,这种良好的生物活性决定因素在正丙硫基,唐除痴等的最新研究结果也证实     

萃取最小溶剂比的计算机图解

用Ａｃａｄ系统和Ｌｉｓｐ语言编程对逆流萃取过程的最小溶剂比进行计算机图解，可省去许多复杂的中间步骤，得到清楚明了的图形结果。     

教学实验用溶剂回收经验数例

在物理化学实验中,经常使用苯、环己烷等有机溶剂。这些溶剂或有较大的毒性,或价格较贵,实验后的废液冲入下水道则污染环境,且造成浪费。如加以回收并经过适当的处理后循环使用,则可避免对环境的污染,又可节省资金,具有一定的实际意义。     

PARTICLE COATING BY CHEMICAL VAPOR DEPOSITION IN A FLUIDIZED BED REACTOR

Aluminum coatings were created onto glass beads by chemical vapor deposition in a fluidized bed reactor at different temperatures. Nitrogen was enriched with Triisobutylaluminum (TIBA) vapor and the latter was thermally decomposed inside the fluidized bed to deposit the elemental aluminum. To ensure homogeneous coating on the bed material, the fluidizing conditions necessary to avoid agglomeration were investigated for a broad range of temperatures.The deposition reaction was modeled on the basis of a discrete particle simulation to gain insight into homogeneity and thickness of the coating throughout the bed material. In particular, the take-up of aluminum was traced for selected particles that exhibited a large mass of deposited aluminum.