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在水热条件下,制备出3个配位聚合物,即{[Zn(ca)(iimb)]·0.75H2O}n(1),{[Cd(ca)(iimb)(H2O)]·0.75H2O}n(2)和{[Zn(ca)(bpe)0.5(H2O)]·H2O}n(3)(H2ca=柠康酸,iimb=1-(1-咪唑基)-4-(咪唑基-1''-甲基)苯,bpe=1,2-二(4-吡啶基)乙烯),并通过单晶X射线衍射、红外光谱和元素分析进行结构表征。配合物1是含有一维金属羧酸链的二维网状层。2是具有羧酸桥连双核的一维准梯形链状结构。3是二维波浪层。其中2和3的三维超分子结构由丰富的氢键相互作用形成;而1的三维超分子结构通过范德华力堆积而成。研究了3个配合物的热重分析(TGA),粉末X射线衍射(PXRD)和荧光性质。固态荧光光谱表明3个配合物的发射光谱与相应的辅助配体相似。此外,配合物3在紫外光照射下,在H2O2存在时对亚甲基蓝(MB)的降解表现出良好的光催化活性。 相似文献
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以高比表面积ZrO2为载体,采用浸渍法制备了负载型Pt催化剂,应用于常压下气相巴豆醛加氢反应,考察了Pt负载量和H2还原温度等对巴豆醛选择性加氢性能的影响.实验结果表明,Pt负载量(质量分数)为3%的3Pt/ZrO2催化剂经500℃还原后,具有较高的巴豆醛选择性加氢性能:巴豆醛转化率为27%,巴豆醇的选择性为55%.X射线粉末衍射(XRD)分析,CO化学吸附,NH3程序升温脱附(NH3-TPD)表征结果表明Pt/ZrO2催化剂上Lewis强酸中心和适宜的Pt颗粒(约为8nm)有利于巴豆醛选择性加氢生成巴豆醇. 相似文献
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We perform the high-pressure energy dispersive x-ray diffraction experiments of nickel nanoparticle chain using a synchrotron source under quasi-hydrostatic compression up to 44.7GPa. There is no phase transition over the pressure range. The bulk modulus Ko, the first pressure derivative of bulk modulus K'0 and the volume Vo are calculated from the pressure-volume data using the Birch-Murnaghan equation of state. A decrease of compressibility is observed, in agreement with the Hall-Perch effect. 相似文献
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A novel ionic compound [Fe(CN)6(phCH2NC5H5)3]·(H2O)4(Mr = 794.71) has been synthesized and its structure was characterized by IR, elemental analysis and X-ray diffraction. The compound crystallizes in monoclinic, space group P21/c with a = 10.837(2), b = 16.551(3), c = 23.402(5) (A), β = 97.531(4)°V = 4161.0(15)(A)3, Z = 4, Dc = 1.269 g/cm3, F(000) = 1668, μ = 0.414 mm-1, R = 0.0479 and wR = 0.1232. The building unit of the title compound consists of three (phCH2N C5H5) ions, one [Fe(CN)6]3- anion and four water molecules. According to the structural analysis, [Fe(CN)6]3- are linked together by O-H…N and O-H…O hydrogen bonds, but [Fe(CN)6]3- and [(phCH2N C5H5)3] ions are bound by electrostatic force to form an ionic compound.Keywords: N-benzyl-pyridine, ferricyanic anion, crystal structure, supramolecular, ionic compound. 相似文献
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采用微波辅助提取法,以总黄酮含量为考察指标,通过单因素实验和正交试验优选出峨嵋岩白菜叶和根状茎总黄酮微波最佳提取工艺.实验结果表明,峨嵋岩白菜叶中总黄酮提取的最佳工艺条件为:乙醇浓度60%.料液比1:30.微波时间60s/次,微波功率480w,提取次数为3次,黄酮含量为15.181mg/g;根状茎中总黄酮最佳工艺条件为:乙醇浓度60%,料液比1:20,微波时间75s/次,微波功率480w,提取次数为2次,黄酮含量为2.066mg/g.峨嵋岩白菜叶中总黄酮含量较根状茎中丰富,微波辅助提取法适合峨嵋岩白菜有效成分的提取. 相似文献
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电解水制氧是一种非常有吸引力的转化储存间歇式能源的技术.本文着重研究了非晶态钴硼合金的电解水产氧性能.非晶态钴硼合金可以通过硼氢化钠直接还原钴盐来获取,并表现出较高的电化学活性.对钴硼合金的弱氧化,产生了类水滑石结构的钴氢氧化物,可进一步提高该类催化剂的整体催化活性,达到接近商业催化剂水平. 相似文献
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This comment points out to a mistake in the main equation of Solteiro Pires et al. (Nonlinear Dyn. 61:295–301, 2010) concerning the fractional velocity in particle swarm optimization. The correct fractional velocity equation is provided and simulation experiments are redone in the comment. 相似文献
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Neutron diffraction methods are used to refine the structure of SrRu(0.8)Ni(0.2)O(3) at room temperature and 4 K. X-ray absorption measurements at the Ru L-edge demonstrate that partial oxidation of the Ru(4+) to Ru(5+) occurs upon introducing Ni into the SrRuO(3) structure to form SrRu(0.8)Ni(0.2)O(3). Whilst the diffraction measurements show that SrRu(0.8)Ni(0.2)O(3) is isostructural with SrRuO(3), the Ni doped compound exhibits an unusual first order orthorhombic-cubic phase transition near 670 K as revealed by x-ray diffraction. The Curie temperature in SrRu(0.8)Ni(0.2)O(3) is lower than that found in SrRuO(3) as a consequence of local distortions reducing the p-d hybridization. 相似文献
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