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991.
The in-situ transient ESR measurements reveal that the oxidized structure (PP++) of polypyrrole (PP) films has an electrocatalytic activity to the oxidation of pyrrole during the electropolymerization process. Surface-enhanced resonance Raman scattering (SERRS) effect was used to probe the structure of PP films in very early stages of the polymerization on gold electrodes. It is of special interest that the electropolymerization can take place at much less positive potentials (about 300 mV) under the irradiation of light. This photocatalytic effect may be applied to the pattern deposition of polymers. 相似文献
992.
The title compound, [Ni(tssb)(2,2-bipy)2]·5(H2O) 1 (tssbH2 =2-[(E)-(2-oxido-phenyl)methyleneamino]ethanesulfonato, 2,2-bipy = 2,2'-bipyridinyl), belongs to orthorhombic,space group Pbcn with a = 20.3983(18), b = 17.6929(15), c = 17.0897(15) nm, V = 6167.8(9) nm3,Mr= 688.38, Z = 8, Dc = 1.481 g·cm-3, F(000) = 2880, μ = 0.758 mm-1 and S =1.099. Each NiⅡ atom is six-coordinated by one N and one O atoms from one tssb2- anion and four N atoms from two 2,2-bipy ligands to give a distorted octahedral geometry. Noticeably, there exists a rare octa-membered water ring which presents a 1D chain by sulfonic group. 相似文献
993.
ZENG Long-Mei ZHONG Yong-Li SU Jing-YuDepartment of Chemistry Zhongshan University Guangzhou Guangdong ChinaWU Hou-Ming MA KanState Key Laboratory of Bio-organic Natural Products Chemistry Shanghai Institute of Organic Chemistry Shanghai China 《中国化学》1996,(4)
A novel skeleton compound benkarlaol (1) was isolated from the red alga Laurencia karlae Zhang et Xia, collected from the Nansha Islands in the South China Sea. Its structure and relative stereochemistry were determined by spectroscopic data, especially extensive 1D and 2D NMR experiments. 相似文献
994.
应用离子色谱离线螯合及ICP-MS测定海水中多种痕量元素 总被引:1,自引:0,他引:1
简要介绍如何构建和运用离子色谱离线螯合系统结合ICP-MS方法分析海水中的痕量元素. 相似文献
995.
N503萃淋树脂吸萃铟的研究 总被引:6,自引:0,他引:6
考察了N_(503)萃淋树脂在盐酸、氢溴酸、硫酸-溴化钠体系中对铟的吸萃性能,研究了N_(503)萃淋树脂在氢溴酸体系中吸萃铟的动力学和机理,发现N_(503)萃淋树脂吸萃铟的反应按假一级反应进行,并符合Freundlich等温吸附式。吸附平衡和红外光谱研究发现N_(503)萃淋树脂吸附铟的反应按下式进行: 相似文献
996.
Mn改性Ni/K/MoS2合成低碳醇催化剂反应性能研究 总被引:4,自引:0,他引:4
以不同的添加方式在Ni/K/MoS2催化剂中加入Mn助剂,考察其合成醇反应性能。结果表明,Mn/Ni/K/MoS2催化剂具有较好的合成低碳混合醇反应性能。共沉淀法以醋酸锰为前驱体加入0.6%的Mn助剂后,C2+含量,醇时空产率及选择性均明显提高;分步沉淀法使Mn的加入量增加到0.6%,醇时空产率明显增加。以浸渍法按化学计量加入Mn助剂考察其含量对催化剂合成醇性能的影响,当Mn/Mo(原子比)为1∶时,反应条件为315 ℃, 9.5 MPa, 6 000 h-1,醇时空产率和醇选择性分别达到最高值0.338?g/mL·h和69.6%。300 h的稳定性测试结果表明,共沉淀法改性的催化剂具有良好的稳定性。 相似文献
997.
采用表面改性法制备了负载型NiO-TiO2/SiO2复合半导体材料,用X射线衍射、比表面测定、透射电镜、红外光谱、拉曼光谱、紫外-可见漫反射等技术,研究了光催化材料的物相结构、微粒尺寸、光响应性能及其能带结构.结果表明:复合半导体材料具有较高的比表面积,NiO和TiO2在材料表面产生相互修饰作用,NiO的加入促进了TiO2在载体表面的分散程度,两者复合后部分地形成了Ni-O-Ti键联.复合后的NiO-TiO2/SiO2增强了对紫外光的吸收性能,而且NiO与TiO2间的n-p复合效应改变了原来TiO2单一的能带结构,有效的抑制了光生电子和空穴的复合,从而明显提高材料的光催化性能. 相似文献
998.
With the extensive investigation of the Michael reaction, not the methylene compounds activated by electron withdrawing group[1,2] but other activated unsaturated compounds containing such as activate N-H or O-H have been used as Michael acceptor.[3,4] However, the research on the Michael reaction of 2,4-dioxohexahydro-1,3,5-triazine (DHT) has not been reported. After the systematic researches on the substitution reactions of DHT, we first report the Michael reaction of DHT with acrylic esters in this paper. 相似文献
999.
Diketo acid derivatives are potent and selective HIV-1 integrase inhibitors. To investigate the detailed synthesis of those derivatives, a series of p/m-[p-(un)substituted phenylsulfonamido]phenyl β-diketo acid derivatives have been designed and synthesized. The quinoxalone derivatives as the potential bioisosteres of the biologically labile β-diketoacid pharmacophores have also been synthesized from reactions of the corresponding diketo acids with o-phenylenediamine. The structures of all diketo acid (ester) and quinoxalone derivatives were confirmed by 1^H NMR, 13^C NMR, IR, HRMS and/or MS (ESI). X-ray crystallographic analysis of 11b demonstrates a similar arrangement of the side chain of quinoxalone derivatives with the parent diketoacids due to the intramolecular hydrogen bond (O…H-N) and the sp^2 hybridization configuration of the two nitrogen atoms of the quinoxalone ring. 相似文献
1000.
An efficient procedure for the synthesis of caffeoyl-and galloyl-containing β-diketoacid derivatives linked byarylamide was reported by,in the key step,dissolving the corresponding phenyl methyl ketone in THF/DME in thepresence of NaOMe as base and dimethyl oxalate as oxalylation reagent,and then separating the sodium ketoe-nolate ester.The resulting β-diketoacids underwent further condensation reaction with o-phenylenediamine to gen-erate quinoxalone derivatives in good yield,rather than 2-benzimidazol.The preliminary ion binding properties ofquinoxalone derivatives were also investigated.UV-Vis spectra showed that these compounds could selectively rec-ognize Cu~(2 )ion in ethanol and form a 1∶2 complex. 相似文献