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991.
Ming‐Lin Guo Feng‐Qin Wang 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(12):m379-m383
The coordination mode of the dimethylmalonate ligand in the two title CuII complexes, {[Cu(C5H3O4)(H2O)]·H2O}n, (I), and [Cu(C5H3O4)(H2O)]n, (II), is the same, with chelated six‐membered, bis‐monodentate and bridging bonding modes. However, the coordination environment of the CuII atoms, the connectivity of their metal–organic frameworks and their hydrogen‐bonding interactions are different. Complex (I) has a perfect square‐pyramidal CuII environment with the aqua ligand in the apical position, and only one type of square grid consisting of CuII atoms linked via carboxylate bridges to three dimethylmalonate ligands, with weak hydrogen‐bond interactions within and between its two‐dimensional layers. Complex (II) has a coordination geometry that is closer to square pyramidal than trigonal bipyramidal for its CuII atoms with the aqua ligand now in the basal plane. Its two‐dimensional layer structure comprises two alternating grids, which involve two and four different dimethylmalonate anions, respectively. There are strong hydrogen bonds only within its layers. 相似文献
992.
In this communication, β‐cyclodextrin modified quantum dots were used as a water‐soluble “supramolecular” cross‐linker (SCL) because of its surface's supramolecular activity. The guest monomer‐loaded SCL (mSCL) can be used to copolymerize with water‐soluble monomers leading to transparent hybrid supramolecular hydrogels. This simple and versatile method opens new venues for the preparation of hybrid supramolecular hydrogels and the host–guest chemistry of cyclodextrins.
993.
994.
The electronic structures and optical properties of rocksalt indium nitride (InN) under pres-sure were studied using the first-principles calculation by considering the exchange and cor-relation potentials with the generalized gradient approximation. The calculated lattice con-stant shows good agreement with the experimental value. It is interestingly found that the band gap energy Eg at the Γ or X point remarkably increases with increasing pressure, but Eg at the L point does not increase obviously. The pressure coefficient of Eg is calculated to be 44 meV/GPa at the Γ point. Moreover, the optical properties of rocksalt InN were calculated and discussed based on the calculated band structures and electronic density of states. 相似文献
995.
Chun Xian Guo Zhi Song Lu Yu Lei Chang Ming Li 《Electrochemistry communications》2010,12(9):1237-1240
A new ionic liquid (IL)–graphene composite prepared by combining IL and a three-dimensional graphene material with large specific surface area and pronounced mesoporosity was used for ultratrace trinitrotoluene detection, showing low background current, high sensitivity of 1.65 μA cm?2 per ppb, low detection limit of 0.5 ppb and good reproducibility, which is much superior to that demonstrated by the IL–CNT and IL–graphite composites. The preparation of IL–graphene composite expands the scope of IL-based electrochemical devices. 相似文献
996.
A method based on MCE coupled with chemiluminescence (CL) detection was developed for the determination of taurine (Tau) and amino acids including alanine (Ala), glycine (Gly), tryptophan (Trp), glutamic acid (Glu) and aspartic acid (Asp) present in mice single fibrosarcoma (S180) cells. Cell injection, loading, cytolysis, electrophoretic separation and CL detection were integrated onto a simple double‐T microfluidic chip. The intracellular constituents were electrophoretically separated within 150 s. The CL detection was based on the enhancement effects of Tau and amino acids on the CL reaction of luminol with H2O2 and Cu2+. The average amounts of Tau, Trp, Gly, Ala, Glu and Asp in per S180 cell from a cell population were 4.73, 1.23, 2.65, 1.94, 1.61 and 1.99 fmol. Ten S180 cells were analyzed, and the contents of Tau, Trp, Gly, Ala, Glu and Asp in mice single S180 cells were found to be in the range of 1.78–8.84, 0.95–2.31, 1.08–6.87, 1.03–4.05, 0.84–2.61 and 0.82–3.68 fmol, respectively. This work demonstrates that MCE coupled with CL detection is a useful analytical tool that is simple, quick and highly sensitive for single‐cell analysis. 相似文献
997.
Xiangli Liu Ping Fan Ming Chen Hossam Hefesha GerhardK.E. Scriba Detlef Gabel Alfred Fahr 《Helvetica chimica acta》2010,93(2):203-211
The objective of this study was to investigate drug–membrane interaction by immobilized liposome chromatography (ILC; expressed as lipophilicity index log Ks) and the comparison with lipophilicity indices obtained by liposome/H2O, octan‐1‐ol/H2O, and immobilized artificial membrane (IAM) systems. A set of structurally diverse monofunctional compounds and drugs (nonsteroidal anti‐inflammatory drugs and β‐blockers) were selected in this study. This set of solutes consists of basic or acidic functionalities which are positively or negatively charged at physiological pH 7.4. No correlation was found between log Ks from ILC and lipophilicity indices from any of the other membrane model systems for the whole set of compounds. For structurally related compounds, significant correlations could be established between log Ks from ILC and lipophilicity indices from IAM chromatography and octan‐1‐ol/H2O. However, ILC and liposome/H2O systems only yield parallel partitioning information for structurally related large molecules. For hydrophilic compounds, the balance between electrostatic and hydrophobic interactions dominating drug partitioning is different in these two systems. 相似文献
998.
Ming‐Lin Guo Feng‐Qin Wang 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(7):m184-m187
The title complex, [CaCu(C5H6O4)2(H2O)2]n, is the first heterobimetallic complex based on a substituted malonate dianion. The CuII cation and two independent 2,2‐dimethylmalonate (or 2,2‐dimethylpropanedioate) dianions build up a robust dianionic [Cu(C5H6O4)2]2− complex, which acts as a building block to coordinate to four Ca2+ cations. Each CuII centre is in a four‐coordinate square plane of dimethylmalonate O atoms, while each CaII atom is in an eight‐coordinate distorted bicapped trigonal–prismatic environment of six O atoms from four different dimethylmalonate groups and two water molecules. This arrangement creates a two‐dimensional layer connectivity of the structure. The dianionic [Cu(C5H6O4)2]2− units are involved in different intermolecular hydrogen‐bonding interactions with water molecules via the formation of hydrogen‐bonded rings of graph sets R12(8) and R(6) within this layer. The crystal was nonmerohedrally twinned by rotation about [011] with a major twin volume fraction of 0.513 (3). 相似文献
999.
1000.
The title complex, [Mn2(L)2(1,3-BDC)2]·0.25H2O 1 (L=2-(2-chloro-6-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline and 1,3-H2BDC=1,3-benzenedicarboxylic acid) has been obtained by using hydrothermal synthesis and characterized by elemental analysis, IR and single-crystal X-ray diffraction. It crystallizes in monoclinic, space group P21/n with a=1.751 68(6) nm, b=1.160 14(4) nm, c=2.585 30(8) nm, β=104.331(4)°, V=5.090 3(3) nm3, Z=4, C54H28.50Cl2F2Mn2N8O8.25, Mr=1 140.13, Dc=1.488 g·cm-3, F(000)=2 306, μ(Mo Kα)=0.673 mm-1, R=0.060 5 and wR=0.161 6. The compound 1 exhibits two-dimensional wavy layer structures, which are further stacked through π-π interactions to form three-dimensional supramolecular architectures. CCDC: 760201. 相似文献