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排序方式: 共有151条查询结果,搜索用时 140 毫秒
1.
Highly Efficient One‐Pot Preparation of 1,2,4‐Oxadiazoles in the Presence of Diazabicycloundecene
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New highly efficient method for the cyclization of acylamidoximes in the presence of diazabicycloundecene was developed and incorporated into a general and practical one‐pot synthesis of 1,2,4‐oxadiazoles (11 examples, 85–97% yields). 相似文献
2.
Journal of Thermal Analysis and Calorimetry - In the present investigation, gene expression programming (GEP) is used to predict thermal conductivity of nanofluids consisting of $$\hbox {Al}_2\hbox... 相似文献
3.
Vimal Kumar K. Appa Rao B. V. Hebalkar Neha Yeshwanta 《Research on Chemical Intermediates》2017,43(10):5811-5828
Research on Chemical Intermediates - Heterocyclic organic molecules containing oxygen, nitrogen or sulfur are generally used as inhibitors for corrosion protection of copper. These compounds form... 相似文献
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N,N-Dimethylaminoalkyl chalcogenolate Pd(II) complexes [PdCl(E∩NMe2)]n has been investigated as a moisture/air-stable and robust catalyst for Sonogashira cross-coupling reaction in the absence of copper and phosphine ligand. The dimeric palladium(II) complex of selenium containing ligand shows the best catalytic activity as compared with monomeric and trimeric complexes. The variety of functional groups are tolerated under optimized catalytic systems and provide excellent yields of the products. 相似文献
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N. Sankara Subramanian R. Vivek Sabaapathy P. Vickraman G. Vimal Kumar R. Sriram B. Santhi 《Ionics》2007,13(5):323-328
P-type porous silicon (PS) structure has been prepared by anodic electrochemical etching process under optimized conditions.
Photoluminescence studies of the PS structure show emission at longer wavelengths (red) for the excitation at 365 nm. Scanning
electron microscope investigations of the PS surface confirm the formation of uniform porous structure, and the pore diameter
have been estimated as 25 μm. Pd:SnO2/PS/p-Si heterojunction with top gold ohmic contact developed by conventional methods has been used as the sensor device.
Sensing properties of the device towards liquefied petroleum gas (LPG) and NO2 gas have been investigated in an indigenously developed sensor test rig. The response and recovery characteristics of the
sensor device at different operating temperatures show short response time for LPG. From the studies, maximum sensitivity
and optimum operating temperature of the device towards LPG and NO2 gas sensing has been estimated as 69% at 180 °C and 52% at 220 °C, respectively. The developed sensor device shows a short
response time of 25 and 57 s for sensing LPG and NO2 gases, respectively.
Paper presented at the Third International Conference on Ionic Devices (ICID 2006), Chennai, Tamilnadu, India, Dec. 7–9, 2006. 相似文献
8.
Treatment of [PtCl2(Ptolyl3)2] (tolyl = 4-MeC6H4) with Na2S in benzene gave [Pt2(μ2-S)2(Ptolyl3)4] (1), which is soluble in common organic solvents. Reactions of (1) with various metal complexes have been studied and several polynuclear metal aggregates isolated. These new complexes were
characterized by elemental analysis and n.m.r. spectroscopy.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
9.
Eltayib Hassan Ahmed Tripti Raghavendra Datta Madamwar 《Applied biochemistry and biotechnology》2010,160(7):2102-2113
A mesophilic bacterial culture producing a novel thermostable alkaline lipase was isolated from oil rich soil sample and identified
as Bacillus subtilis EH 37. The lipase was partially purified by ammonium sulfate precipitation and hydrophobic interaction chromatography with
17.8-fold purification and 41.9 U/ml specific activity. The partially purified enzyme exhibited maximum activity at pH 8.0
and at 60 °C. It retained 100% of activity at 50 °C and 60 °C for 60 min. The presence of Ca+2, Mg+2, and Zn2+ exhibited stimulatory effect on lipase activity, whereas Fe+3 and Co+2 reduced its activity. The enzyme retained more than 80% of its initial activity upon exposure to organic solvents, exhibited
107% and 115% activity in the presence of 15% isopropyl alcohol and 30% n-hexane, respectively. The EH 37 lipase also proved
to be an efficient catalyst in synthesis of ethyl caprylate in organic solvent, thus providing a concept of application of
B. subtilis lipase in non-aqueous catalysis. 相似文献
10.
Reactions of [Pt2(μ-Cl)2(C∩P)2] (C∩P = CH2C(Me2)PBut2-C,P) with various anionic ligands differing in ligand bite and denticity have been investigated and the resulting products have been characterized by elemental analyses and NMR (1H, 13C, 31P, 195Pt) spectroscopy. Stereochemistry of the complexes has been deduced by NMR spectroscopy. Structures of [Pt2(μ-SPh)2(C∩P)2], [Pt2(μ-pz)2(C∩P)2], [PtCl(Spy)(PBut3)], [Pt2(μ-SCOPh)2(C∩P)2] and [Pt{S2P(OPri)2}(C∩P)] have been established by single crystal X-ray diffraction analyses. The complex [Pt2(μ-SPh)2(C∩P)2] adopts a sym cis configuration while other binuclear complexes exist in a sym trans configuration. The molecular structure of [Pt{S2P(OPri)2}(C∩P)] revealed that complex comprises of two four-membered chelate rings but in solution a dimeric structure based on 195Pt NMR data has been suggested. 相似文献