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751.
Yang Guo Yue Ma Na Zhou Zhan‐Quan Liu Qing‐Lun Wang Shi‐Ping Yan Dai‐Zheng Liao Prof. Dr. 《无机化学与普通化学杂志》2010,636(5):865-871
To investigate the influence of the non‐covalent interactions, such as hydrogen‐bonding, π–π packing and d10–d10 interactions in the supramolecular motifs, three cyanido‐bridged heterobimetallic discrete complexes {Mn(bipy)2(H2O)[Ag(CN)2]}[Ag(CN)2] ( 1 ), {Mn(phen)2(H2O)[Au(CN)2]}2[Au(CN)2]2 · 4H2O ( 2 ), and {Cd(bipy)2(H2O)[Au(CN)2]}[Au(CN)2] ( 3 ) (bipy = 2,2′‐bipyridine, and phen = 1,10‐phenanthroline), which are based on dicyanidometallate(I) groups with 1:2 stoichiometry of metal ions and 2,2′‐bipyridyl‐like co‐ligands were synthesized and structurally characterized. In compound 1 , hydrogen bonding and π–π interactions governed the supramolecular contacts. In compound 2 , the incorporation of aurophilic, hydrogen bonding and π–π interactions result in a 3D supramolecular network. In compound 3 , hydrogen bonding and π–π stacking interactions result in a 2D supramolecular layer. In the three complexes, hydrogen‐bonding, π–π packing and/or d10–d10 interactions can play important roles in increasing the dimensionality of supramolecular assemblies. 相似文献
752.
Structural stability of the perovskite-type GdMnO(3) has been investigated by the synchrotron angle-dispersive x-ray diffraction technique up to 63 GPa in a diamond anvil cell. GdMnO(3) stays in an orthorhombic structure but undergoes an isostructural phase transition with ~5% volume reduction at 50 GPa. In the parent orthorhombic phase, the compressions along a, b and c axes exhibit a large anisotropic behavior. With increasing pressure, our results show that the distortion and tilts of the MnO(6) octahedra are reduced continuously and the orthorhombic structure evolves towards higher symmetry. By fitting the observed pressure-volume data using the third-order Birch-Murnaghan equation of state, we obtain the bulk modulus B(0) = 156(3) GPa with B(0)' = 6.5(3) for the starting orthorhombic phase. Upon decompression, the starting orthorhombic phase is recovered. 相似文献
753.
The objective of this research was to investigate the possibility of solving the influence of the magnetostatic surface wave (MSSW) propagating velocity on the bandwidths of the single-scale wavelet transform processor using MSSW device. The motivation for this work was prompted by the processor that −3 dB bandwidth varies as the propagating velocity of MSSW changes.In this paper, we present the influence of the magnetostatic surface wave (MSSW) propagating velocity on the bandwidths as the key problem of the single-scale wavelet transform processor using MSSW device. The solution to the problem is achieved in this study. we derived the function between the propagating velocity of MSSW and the −3 dB bandwidth, so we know from the function that −3 dB bandwidth of the single-scale wavelet transform processor using MSSW device varies as the propagating velocity of MSSW changes. Through adjusting the distance and orientation of the permanent magnet, we can implement the control of the MSSW propagating velocity, so that the influence of the MSSW propagating velocity on the bandwidths of the single-scale wavelet transform processor using MSSW device is solved. 相似文献
754.
Chloroformylation of 5,5‐dimethyl‐1,2‐ oxathiolan‐4‐one 2,2‐dioxide 4 with Vilsmeier reagent (DMF/POCl3) led to the formation of cyclic β‐chloro‐vinylaldehyde (4‐chloro‐5,5‐dimethyl‐3‐formyl‐1,2‐oxathiolene 2,2‐dioxide 5 ). Compound 5 reacted with formamidine, o‐aminophenol, 1,2‐phenylenediamine, aminopyrazole, and aminotetrazole to give the corresponding heterocyclic compounds. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:200–204, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20094 相似文献
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流动注射在线吸着分离预浓集冷蒸气原子吸收法测定痕量镉 总被引:3,自引:0,他引:3
研究了IRC-718离子交换树脂、122螯合树脂和MuromacA-1树脂对镉的预浓集条件,建立了超痕量镉的流动注射在线吸着分离预浓集冷蒸气发生原子吸收光谱测定方法.在每小时进样60,60和45次速度下检出限(3σ)分别为3.0,3.0和2.4ng/L.线性范围0~0.3μg/L,对0.2μg/L镉测定的相对标准偏差为2.0%~2.6%(n=11).讨论了用这3种离子交换树脂微柱进行分离预浓集时条件参数的优化、抗干扰能力以及对天然水样的回收率,并分别进行了水样的测定. 相似文献
758.
Chaobin He Zhihua Lu Lun Zhao Tai-Shung Chung 《Journal of polymer science. Part A, Polymer chemistry》2001,39(8):1242-1248
Wholly aromatic main-chain rigid-chain polymers containing meta- and orthokink linkages were synthesized. The thermal property, liquid crystallinity, and crystalline structure were studied using DSC, polarized light microscopy, and wide-angle X-ray scattering. These polymers exhibited liquid crystallinity up to 50 mol % of meta- and orthokink linkages. The existence of liquid crystallinity in these polymers may be attributed to the adoption of cis conformation in kink units in these polymers because the energy penalty for doing so can be compensated by the formation of the liquid–crystalline phase. The crystallinity of the polymers was low, and the crystal structure was quite similar to that of the pure polymers (without kink units). This can be explained by that fact that the crystal region mainly consists of the nonkink units, and the kink units disrupt the crystallization of the polymers and form defects. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1242–1248, 2001 相似文献
759.
功能性CdS纳米荧光探针荧光增敏法测定人血清白蛋白 总被引:12,自引:1,他引:11
目前 ,以荧光分析法对蛋白质进行研究主要采用有机荧光探针[1~ 3 ] .与传统的有机染料 (如罗丹明 )探针相比 ,半导体纳米晶体探针的光强度要高 2 0倍 ,光稳定性要高 1 0 0倍 ,谱线宽度只是有机染料谱线宽度的 1 /3 [4 ] .将半导体纳米晶体作为探针用于测定生物分子 ,将大大提高分析的灵敏度和选择性 ,而目前其应用于生物染色、医疗诊断、DNA序列测定和免疫分析等方面的研究很少 [4 ,5] .本文合成了胶态纳米粒子 Cd S,并在其外表面修饰一层巯基乙酸 ,使其具有水溶性 ,并能与生物分子作用 ,从而可利用其外表面的功能性基团对人血清白蛋白进… 相似文献
760.