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91.
Chang Xiu Han Ji Li Ren Xue Jiao Tang Bao Gui Zhang 《中国化学快报》2007,18(10):1285-1288
A new ternary Fe-based alloy catalyst FeCuP applied to decompose PH_3 was prepared with low-cost material by chemical reduction deposition method.The properties of it were characterized by XRD,ICP and SEM.Its catalytic activity on the decomposition of PH_3 and the decomposition conditions were studied.FeCuP alloy exhibits high thermal stabilities and high catalytic activity.Using it as catalyst,the decomposition temperature of phosphine decreases from over 800℃to 400-500℃.The decomposition rate of phosphine achieved 100%. 相似文献
92.
三辛基氧化膦(TOPO)萃取铟的研究 总被引:2,自引:0,他引:2
本文研究了三辛基氧化膦(TOPO)自盐酸溶液中萃取铟的性能,其萃取率是随酸度的增加而增加。与P_(350)和TBP相比较,萃取能力大小顺序为:TOPO>P_(350)>TBP经斜率法和化学分析法研究确定,TOPO白盐酸溶液中萃取铟的反应为:In_((a))~(3+)+H_((a))~++4Cl_((a))~-+2TOPO_((o))F(?)HInCl_4·2TOPO_((o))IR和NMR研究证明:铟是以H[InCl_4]形式被萃入TOPO有机相中的。 相似文献
93.
Instead of environmentally toxic chromium oxidant, singlet oxygen generated photcchemically was used as environmentally friendly and benign oxidizing agent to accomplish the transformation of pseudodiosgenin diacetate to diosone efficiently in a low toxic and less expensive solvent acetone. Accordingly 16-dehydropregnenolone acetate(16-DPA), an important intermediate for preparation of steroidal drugs, was prepared in good yield (75%) when photoreaction was run in acetone/acetic anhydride/pyridine system. The mild reaction condition as well as simple and environmentally friendly process made the method commercially viable and important for production of 16-DPA in industrial scale. 相似文献
94.
Hong-Bing Ji Ting Ting Wang Le-Fu Wang Yan-Xiong Fang 《Reaction Kinetics and Catalysis Letters》2007,90(2):259-266
A reusable solid catalyst, MnFe1.8Cu0.15Ru0.05O4, has been developed as an effective catalyst for the aerobic oxidation of sulfides and sulfoxides to sulfones. The ruthenium
modified spinel catalyst is the first example reported for such reaction under mild condition with molecular oxygen as the
only oxidant. The oxidation reaction proceeded via an electrophilic attack of the oxygen atom of the catalyst on the electron-rich
sulfur atom of the substrate. 相似文献
95.
通过4,4’-一氧二(异氰酸苯酯)与异丙醇加成反应,合成标题化合物 4,4’-一氧二(苯胺灵)(Ⅰ) (C20H24N2O5, Mr=372.41),并用X射线衍射、红外光谱、13C核磁共振、电子轰击质谱和元素分析对标题化合物进行表征. 晶体属于三斜晶系,空间群为P1晶体学参数为: a=0.85107(17), b=0.91164(18), c=1.45701(3) nm, α=80.44(3)°, β=85.25(3)°, γ=62.88(3)°, V=0.9922(3) nm3, Z=2, Dc=1.247 g•cm-3, μ(Mo Kα)=0.90 cm-1, F(000)=396.两个苯环平面之间的夹角为62.06° (0.06°). 晶体结构经全矩阵最小二乘法修正,最终偏离因子R=0.0520, wR=0.1434(对可观察点).此化合物应具有广谱的生物活性. 相似文献
96.
A cytotoxic compound from the leaves of Juglans mandshurica 总被引:1,自引:0,他引:1
From Juglans mandshurica leaves, a new quinone compound was isolated through bioassay-guided fractionation. The structure elucidation of the compound was established based on spectroscopic studies, notably of the 2D NMR spectra. The compound exhibited moderate cytotoxic activities against Hela, MCF-7, BGC823 and 3T3-Llcell lines with IC50 ranges from 7.5 to 26.8 μmol/L. 相似文献
97.
Three new serratane triterpenoids, (3α,14α,15α,21α)‐3,14,15,21,29‐pentahydroxyserratan‐24‐oic acid ( 1 ), (3α,21β)‐serrat‐14‐ene‐3,21,24,30‐tetraol ( 2 ), and (3α,21α)‐serrat‐14‐ene‐3,21,24,29‐tetraol ( 3 ), were isolated from Phlegmariurus squarrosus, together with eight known compounds. Their chemical structures were elucidated on the basis of in‐depth spectroscopic analyses. 相似文献
98.
One common approach for designing protein tyrosine phosphatase (PTPase) inhibitors is to incorporate a nonhydrolyzable phosphotyrosine (pTyr) mimic into a peptide substrate for PTPases. This report describes the synthesis of three such nonhydrolyzable pTyr mimics that contain alpha-ketoacid, alpha-hydroxyacid, and methylenesulfonamide functional groups in place of the phosphate. These pTyr mimics were incorporated into the peptide sequence Ac-Asp-Ala-Asp-Glu-X-Leu-NH(2), where X is the pTyr mimic, and analyzed for activity against the Yersinia PTPase and PTP1B. 相似文献
99.
Two copper complexes [Cu(TTA)2(4,4′‐azpy)] (1) and [Cu‐(TTA)2(3,3′‐azpy)] (2) (HTTA = 1,1,1‐trifluoro‐3‐(2‐thenoyl)‐acetone, 4,4′‐azpy = 4,4′‐azobispyridine, 3,3′‐azpy = 3,3′‐azobispyridine) were synthesized and characterized. The crystal structures were determined by X‐ray diffraction analysis. The crystal 1 belongs to triclinic with space group P1 , a = 0.8515(2) nm, b = 0.9259(2) nm, c = 0.9468(2) nm, a = 66.126(9)°, β = 79.667(9)°, γ = 90.13(1)°, Z = 1, V = 0.6692(2) nm3, Dc = 3.425 g/cm3, γ = 2.113 mm?1, F(000) = 694, R1 = 0.0594, wR2 = 0.1499. The crystal 2 belongs to monoclinic with space group P21/c, a = 1.0661(2) nm, b = 1.4296(3) ran, c = 1.0041(3) nm, β = 114.50(3)°, V = 1.3926(5) nm3, Z = 2, Dc = 1.646 g/ cm3, μ = 1.015 mm?1, F(000) = 694, R1, = 0.0535, wR2 = 0.1113. In the crystals of complexes 1 and 2, the copper atoms have distorted octahedral symmetry. The two compounds possess very similar one‐dimensional linear chains linked through the rodlike 4,4′‐azpy ligands or 3,3′‐azpy ligands. 相似文献
100.
With P(CH3)3 as the probe molecule adsorbed on titanium silicalite (TS-1) zeolite, the special and important role of T12 site in MFI-type zeolite was clearly elucidated. There are altogether three active sites present in TS-1 zeolite with Ti at the T12 site. Owing to the preferential adsorption of probe molecules on the first Brönsted acidic site, the Ti12 center will probably fail to show Lewis acidity. The ionic [HP(CH3)3]+ species can be stabilized by the first or second Brönsted acidic site, with the former energetically favored. The latter was formed through the transfer of the ionic [HP(CH3)3]+ species from the first to the second Brönsted acidic site. 相似文献