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Co3O4 纳米棒的溶剂热合成及形成机理分析 总被引:1,自引:0,他引:1
以Co(NO3) 2 ·6H2 O为主要原料 ,H2 O2 为氧化剂 ,在油酸和正十二烷烃的混合溶液中 ,利用溶剂热技术于 160℃反应 10h ,成功地合成了Co3O4 纳米棒 .用X射线粉末衍射 (XRD)、透射电子显微镜 (TEM)和振动样品磁强计 (VSM)等手段对产物进行了表征 ,并对产物的形成机理进行了初步分析 .结果表明 ,产物为立方型Co3O4 纯相 ,优化实验条件可得到棒状Co3O4 ,其平均尺寸约为 2 5× 10 0nm .Co3O4 纳米棒的形成与微乳液的棒状结构有关 ,棒状结构的胶束是形成这种纳米棒的模板 .在室温下 ,产物的矫顽力 (Hc)为 3 5 3Oe ,剩余磁化率 (Mr)为 0 .4emu/g . 相似文献
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近二十年来,多吡啶钌?的配合物引起了人们极大的兴趣。这类配合物的光物理、光化学和电化学性质适合作为研究电子转移和能量迁移的超分子体系的建筑块,而且在光化学分子器件(PMDs)方面具有应用前景犤1~5犦。三-(2,2'-联吡啶)钌?配合物,在可见光区具有强的金属到配体电荷转移吸收带,这种电荷转移跃迁涉及分子内的快速氧化-还原过程。当三-(2,2'-联吡啶)钌?配合物中的一个2,2'-联吡啶分子被其它配体取代后,电荷转移激发态的氧化-还原性质明显受到影响犤6,7犦。通过改变钌?中心周围的配体,可微调钌?中心的… 相似文献
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A novel Ni(II) coordination polymer [Ni(dtba)(4,4′-bpy)] (1, H2dtba = 2,2′-dithio- bisbenzoic acid, 4,4′-bpy = 4,4′-bipyridine) has been synthesized by H2dtba and Ni(CH3COO)2·4H2O with exo-bidentate rigid ligand 4,4′-bpy by using hydrothermal method, and its structure was determined by single-crystal X-ray diffraction. X-ray crystal structure analysis reveals that complex 1 crystallizes in monoclinic, space group Cc with a = 11.7624(9), b = 18.7933(19), c = 10.3071(11), β = 97.6510(10)°, V = 2258.2(4)3, Z = 4, C24H16N2NiO4S2, Mr = 519.22, Dc = 1.527 g/cm3, μ = 1.079 mm-1 and F(000) = 1064. The structure was solved by direct methods and refined to R = 0.0434 and wR = 0.1000 for 3281 observed reflections (I > 2σ(I)). The coordination environment of Ni(II) is a distorted octahedron, and a three-dimensional structure was formed with the coordination effect of dtba2- and 4,4′-bpy ligands. The topological analysis reveals that the whole framework of 1 is a 2-nodal net of (52.6)(53.64.72.8) topology. The thermal stability and XRD pattern of 1 were also investigated. 相似文献
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SiC晶须VLS生长机理及生长动力学研究 总被引:1,自引:1,他引:1
对VLS机理下稻壳合成SiC晶须(SiCw)及生长动力学进行了研究,结果表明,SiO2与C在高温下生成SiO的反应是SiC晶须生长的速率控制步骤;在形成晶须的催化剂作用下,SiC晶须的生长速率与SiO在催化剂熔球周围的浓度成正比;SiC晶须生长的催化选择性温度的增加而提高.复合催化剂可提高合成SiC晶须反应速率及催化选择性。 相似文献
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A novel pyridyl-dicarboxylate Schiff-base ligand (5-((pyridin-3-ylmethyl)amino)isophthalic acid,H2L) and its Zinc(Ⅱ) complex,namely,ZnL (1),were synthesized. The ligand was characterized by NMR analysis. The X-ray crystallographic analysis on complex 1 shows that 1 crystallizes in homoclinic,space group P21/c with a= 0.753 83(10) nm,b=1.040 52(14) nm,c=1.734 67(19) nm,β=112.123(5)°,V=1.260 5(3) nm3,Z=4,Dc=1.769 g· cm-3,F(000)=680,μ=1.966 mm-1,the final R=0.030 8,wR=0.085 6. In complex 1,the coordination environment of Zn(Ⅱ) is distorted tetragonal-pyramid with N1O4 set. The 2D 4,4-topological sheets in 1 packed along a axis to form its 3D framework,which was stabilized by the π…π interactions between the adjacent aromatic rings on the neighbouring sheets. The photoluminescent property of 1 was also investigated. 相似文献
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1 引 言基质辅助激光解吸电离飞行时间 (MALDI TOF)质谱是近年来发展起来的一种“软电离”质谱分析方法 ,具有样品分子不易碎裂 ,准分子离子峰强的优点 ,在多肽、蛋白质、DNA等生物大分子及杯芳烃等重要的有机化合物的分析中得到广泛的应用。但实践证明 ,MALDI TOF质谱还是高分子化合物的有效表征和结构鉴定手段。本文将MALDI TOF质谱用于监控高分子化合物甲基丙烯酸丁酯末端酯基的水解反应的监控。2 实验部分2 .1 仪器和试剂 BiflexIII型MALDI TOF质谱仪 (BrukerDaltoni… 相似文献
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