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951.
The addition-hydrolysis reaction of benzimidazolium salt with some mono- and bifunctional amine nucleophiles is reported,and a novel method of biomimetic synthesis for formamides and heterocycle compounds is provided.  相似文献   
952.
A Facile Synthesis of Squamosamide Cyclic Analogs   总被引:2,自引:0,他引:2  
A series of novel cyclic derivatives have been synthesized by utilizing a nickel powder mediated radical cyclization as the key step. The structures of the new compounds were confirmed by ^lH-NMR and MS.  相似文献   
953.
A novel gel-like process has been developed for synthesizing LiaNi0.8Co0.2O2 powders,using citric acid as a chelating agent. This process improves the homogeneity of constituent cation and enhances their reactivity in the obtained precursor. The results of electrochemical test demonstrated that these materials exhibited excellent electrochemical properties. Its initial capacity reached 181.6 mAh/g and reversible efficiency at the first cycle is about 88.6%.  相似文献   
954.
The hydrolysis of tetraethoxysilane (TEOS) occurred on the surface of poly(methyl methacrylate) (PMMA) microshperes immediately after these microshperes were prepared in TEOS. Micron-sized hollow SiO2 spheres were obtained by calcination of the coated PMMA microshperes. It was found that the final hollow spheres were constituted by small SiO2 particles.  相似文献   
955.
Hybrids of intercalative nitrile-butadiene rubber/organomodified bentonite (NBR/OMB) were prepared by thelatex intercalation technique. Investigation of their mechanical properties and the microstructore of NBR/OMB showed thatthe organomodified bentonite is an effective toughener for NBR. Transmission electronic microscopy (TEM) and X-rnydiffraction (XRD) tests showed that the NBR macromolecule could be intercalated into the galleries of bentonite.Incorporation of NBR/OMB hybrids as tougheners into poly(vinyl chloride) (PVC) results in a substantial increase in theimpact strength of PVC, but little decrease in its tensile strength and flexural strength, compared to the unmodified PVC.  相似文献   
956.
Reaction of a new type of bidentate ligand PhPQu [PhPQu = 2‐diphenylphosphino‐4‐methylquinoline] with Fe(CO)5 in butanol gave trans‐Fe(FpPQu‐P)(CO)3 (1). Compound 1, which can act as a neutral tridentate organometallic ligand, was reacted with I B, II B metal compounds and a rhodium complex to give six binuclear complexes with Fe? M bonds, Fe(CO)3 (μ‐Ph2PQu)MXn (2–7) [M= Zn(II), Cd(II), Hg(II), Cu(I), Ag(I), Rh(I)], and an ion‐pair complex [Fe(CO)3 (μ‐Ph2PQu)2HgI][HgI3]? (8). The structure of 8 was determined by X‐ray crystallography. Complex 8 crystallizes in the space group P‐1 with a = 1.0758(3), b = 1.6210(4), c=1.7155(4)nm; a=75.60(2), β=71.81(2), γ=81.78(2)° and Z = 2 and its structure was refined to give agreement factors of R=0.050 and Rw = 0.057. The Fe‐Hg bond distance is 0.2536nm.  相似文献   
957.
用统计模拟分光光度法测定复方消咳新片4个组分含量。按均匀设计表制备合成样品,绘制溶液的UV-VIS吸收曲线,获得有限但足够的实验数据,用逐步回归法构造反映该复方制剂组分在灵敏波长的吸光度-组分含量经验关系的“最优”数学模型,用改进单纯形法寻优,求出未知样品的各组分含量。磺胺甲基异恶唑、甲氧苄胺嘧啶、盐酸溴已新、枸橼酸维静宁的回收率分别为1003%、1004%、999%、990%,标准差分别为091%、14%、12%、39%。  相似文献   
958.
LnSrNiO4-λ系列复合氧化物的物化性质与对NO分解的催化性能   总被引:16,自引:3,他引:16  
用柠檬酸络合法合成了K2NiF4结构的LnSrNiO4-λ(Ln=La,Pr,Nd,Sm,Gd)系列稀土取代类钙钛石型复合氧化物催化剂,对该系列催化剂的固态物理、化学性质及其对NO分解的催化性能进行研究。结果表明,该系列复合氧化物催化剂对NO分解活性都很高,在此基础上对该系列复合氧化物中稀土元素对NO分解反应的取代效应进行了探讨。  相似文献   
959.
近年来,甲烷部分氧化制合成气(POM)的研究一直十分活跃[1,2].前文报道了用于甲烷部分氧化制合成气的镍基催化剂(Ni/La2O3)在微波场中的升温行为和催化活性[3],发现在达到相同的CH4转化率时,微波活化方式下的催化剂床层温度比常规加热低得多...  相似文献   
960.
This paper reports a prototype for a standard connector between a microfluidic chip and the macro world. This prototype demonstrate a fully functioning socket for a microchip to access the outside world by means of fluids, data signals and energy supply. It supports up to 10 channels for the input and output of liquids or gases, as well as compressed air or vacuum lines for pneumatic power lines. The socket has built-in valves for each flow channel. It also contains 28 pins for the connection of electrical signals and power. Built-in valves make it possible to control the flow in each channel independently. A chip ( 11.0 x 11.0 x 0.9 mm) can be mounted into or dismounted from the socket with one touch. The fluidic connectors of the socket are designed to contact vertically on the top of chip. And the electrical connectors (the spring array) of that physically support the chip and contact lead pads at the bottom of chip. No adhesives or solders are used at any contact points. The pressure limit for the connection of working fluids was 0.2 MPa and the current limit for the electrical connections was 1 A. This socket supports both serial and parallel processing applications. It exhibits great potential for developing microfluidic systems efficiently.  相似文献   
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