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101.
通过水热方法,采用H3CAM(H3CAM=4-hydroxy-pyridine-2,6-dicarboxylic acid)与Cd(NO3)2.4H2O反应,合成了1个镉配位聚合物[Cd4(HCAM)4(H2O)8]n(1),并对其结构和荧光性质进行了研究。结构分析结果表明该配合物属于单斜晶系,C2/c空间群。四个HCAM2-配体桥联4个镉离子形成了1个四核镉单元。这些孤立的单元通过氢键作用形成了1个三维配位框架。研究表明,该配合物在室温下能发出兰色荧光。  相似文献   
102.
A convenient and general method of synthesis of binuclear ruthenium(II) pyridazine complex was reported. The synthesized complex was characterized by analytical and spectral methods. The structure of the complex was confirmed by X-ray diffraction technique and was found to be an efficient catalyst for the transfer hydrogenation of ketones with excellent conversions in the presence of isopropanol/KOH at 82 °C. The effect of solvents, bases, and different catalyst/substrate ratio for the reaction was also investigated.  相似文献   
103.
《Analytical letters》2012,45(1):57-61
Abstract

A new method for the determination of the titre of ascorbic acid standard solutions employing potassium dichromate as a primary standard has been developed. In a pyrophosphate medium, the pyrophosphate complex of divalent manganese is oxidized by dichromate to the pyrophosphate complex of tervalent manganese; the latter oxidizes o-tolidine reversibly with formation of the corresponding quinonediimine, which is visually titrated by the ascorbic acid standard solution.  相似文献   
104.
A rapid,sensitive,selective and reliable strip assay based on DNA-functionalized gold nanoparticles for Hg2+ detection has been developed,with a detection limit 5 nmol/L.The measurement principle was based on thymine-Hg2+-thymine(T-Hg2+-T) coordination chemistry and streptavidin-biotin interaction.The major advantages of this assay are that results can be read visually without any instrument in less than 10 min and that it does not require any sample pretreatment.  相似文献   
105.
106.
《Analytical letters》2012,45(14):1743-1748
Abstract

The chromatographic behaviour of 32 metal ions has been studied on paper Impregnated with Zirconium(IV) antimonate in aqueous HCI and mixed solvent system containing dimethyisul phoxide and dioxane. Several Important binary and ternary separations have been achieved. Quantitative separation of Hg(ll) from Ni2+, Pb2+, Pd2+, Ru3+, Rh3+, Bi3+, Co2+, Cd2+ and Gd3+ is described.  相似文献   
107.

The reaction of CuCl2 with 2-amino-5-cyanopyridine and HCl in 1-propanol gave bis(2-amino-5-cyanopyridinium) diaquadichlorocopper(II) dichloride (1). Crystal data for 1 are: monoclinic, space group: P21/c, a = 8.461(3) Å, b=14.665(5) Å, c=7.883(3) Å, g =96.105(4)°, V=972.6(6) Å 3 , Z=2, Dcalc =1.645 Mg/m3, w =1.691 mm?1, F(OOO)=486, MoK f( u =0.71073 Å), R1=0.0431 for [∣I∣ S 2 σ (I)] and R1=0.0680 for all 1944 unique reflections and 130 parameters. The structure exists as square planar Cu(H2O)2Cl2 units with long semi-coordinate bonds to the cyano nitrogens of the 2-amino-5-cyanopyridinium ions. Hydrogen bonding from the water molecules and N―H hydrogens to the chloride irons stablises the lattice.  相似文献   
108.
Lead(II) 4,4,4-trifluoro-1-naphthyl-1,3-butanedione (Htfnb) complexes of 1,10-phenanthroline (phen) and 2,2′-bipyridine (bpy), [Pb2(bpy)2(tfnb)2] (1) and [Pb2(phen)2(tfnb)2] (2), have been synthesized and characterized by elemental analysis, IR, spectroscopy and X-ray crystallography. The self-assembly of 1 and 2 is likely to be caused by C–H ··· F–C, C–H ··· O and π–π stacking interactions.  相似文献   
109.
A tetranuclear Zn(ΙΙ) complex, [Zn4L2(OAc)2(CH3OH)2] with an unsymmetric Salen-type bisoxime (H3L?=?6-hydroxy-4′,6′-dibromo-2,2′-[ethylenediyldioxybis(nitrilomethylidyne)]diphenol), has been synthesized and structurally characterized. There are two kinds of coordination geometry (trigonal bipyramidal and square pyramidal) in the Zn(ΙΙ) complex. The molecule has serious distortion probably from the asymmetry. The complex exhibits blue emission with the maximum emission wavelength λ max?=?423?nm when excited with 340?nm.  相似文献   
110.
Two new rhenium(I) complexes chelated by a substituted 2,2′-bipyridine with general formula Re(CO)3LCl, where L?=?6?-(2″-methoxyphenyl)-2,2′-bipyridine (L1 ) and 6?-(4″-diphenylaminophenyl)-2,2′-bipyridine (L2 ), are synthesized and characterized by IR, NMR, and elemental analysis. Structure of 1 was determined by single-crystal X-ray crystallography, revealing that rhenium is six-coordinate octahedral. The electrochemical, photophysical, and thermal properties of the two rhenium(I) complexes were investigated. Electroluminescent devices were fabricated by doping 1 in polymer blend host of poly(vinylcarbazole) and 2-tert-butylphenyl-5-biphenyl-1,3,4-oxadiazole using simple solution spin-coating technique. The device exhibits a maximum current efficiency of 2.97?cd?A?1 and peak brightness in excess of 2390?cd?m?2.  相似文献   
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