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A homo‐dinuclear NiII complex was prepared from 2, 6‐bis(3, 5‐dimethylpyrazolyl)pyridine (Me4‐bpp) and azide ions in nonaqueous media. It was characterized by single crystal X‐ray structural analysis, IR spectroscopy, and elemental analysis. In addition, the electrochemical properties of the compound were determined with cyclic voltammetry in DMF. The title compound crystallizes in the P21/n monoclinic space group, with unit cell parameters a = 8.978(1), b = 12.459(1), c = 17.764(1) Å, ß =100.603(3)°, V = 1953.0(3) Å3, Z = 2. The Ni2+ ion has a distorted octahedral environment involving three nitrogen atoms of the Me4‐bpp ligand, two nitrogen atoms from the bridged azide group, and one nitrogen atom from the terminal azide group. The Ni···Ni distance is 3.273(5) Å.  相似文献   
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Abstract  

The dinuclear cadmium(II) complex with 2,6-bis(3,4,5-trimethyl-N-pyrazolyl)pyridine (btmpp) has been synthesized, and characterized by single crystal X-ray diffraction, IR, UV–Vis and TGA–DTA methods. Cd atoms are located in a distorted octahedral environment in the complex. The complex crystalizes in monoclinic space group C 2/c, with unit cell dimensions a = 20.5636(12) Å, b = 14.0167(13) Å, c = 15.6598(11) Å, β = 113.425(5)o, V = 4141.7(5) Å3. There are two intermolecular and a intramolecular hydrogen bonds interactions in crystal.  相似文献   
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A complex of NiII with 2,6-diacetylpyridinedihydrazone (L) towards nickel(II) has been prepared and characterized by means of elemental analyses, IR, electronic spectra and single crystal X-ray analyses. [NiL2](NO3) was crystallized in the tetragonal space group P-4 21 c. The complex exhibits the expected coordination sphere with six nitrogen atoms coordinated to the central NiII with a deformation from pseudo-octahedral geometry. Antimicrobial activities of the ligand and its complex were investigated.  相似文献   
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In this paper, magnetic-molecularly imprinted polymer was used for the preconcentration of trace levels of imidacloprid in water and apple samples prior to liquid chromatography-quadrupole-time-of-flight mass spectrometric determination. The selectivity of the magnetic polymer was united with the sensitivity and the high resolving power of the chromatographic system. The developed method showed a linear range from 10.0 to 500.0 µg/L. The quantitative recoveries were obtained for water and apple samples in the range of 92.0%–99.0 %. The relative standard deviations of intra-day and inter-day tests were found to be in the range of 0.8%–1.2% and 1.2%–1.6 %, respectively. In addition, the same magnetic-molecularly imprinted polymer (MMIP) can be used at least ten cycles for the determination of imidacloprid. The preconcentration factor of the method was found to be 2.5, and the total preconcentration procedure can be completed in 1 h. Characterization of synthesised particles were executed with various techniques. Due to its suitable limit of detection, dynamic linear range, sensitivity and selectivity, the developed method seemed to be ideal for the determination and preconcentration of imidacloprid in water and fruit samples.  相似文献   
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In the title compound, the coordination around the Cu atom is a distorted square-pyramid involving three N atoms from the ligand and one N atom from the azido group at the basal plane. The Cl atom is located at the apical position. The Cu atom is 0.32(5)A above the basal plane. There are three intramolecular and four weak intermolecular hydrogen bonds in the structure. IR spectra confirm the asymmetric N3 stretching vibrations of the terminal azide group.  相似文献   
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Monomeric zinc(II) and mercury(II) complexes containing tripodal nitrogen donor ligand 2,6‐bis(3,4,5‐trimethyl‐N‐pyrazolyl)pyridine (btmpp) were synthesized, and characterized by elemental and spectroscopic (IR, UV/Vis) analyses, TG‐DTA and single‐crystal X‐ray diffraction studies. X‐ray analyses of the complexes [Zn(btmpp)Cl2] ( 2 ) and [Hg(btmpp)(SCN)2] ( 3 ) showed that both structures crystallize in space group P21/c with a = 7.9722(6), b = 18.3084(13), c = 13.3117(9) Å and Z = 4 for 2 and a = 8.7830(3), b = 21.1489(7), c = 12.0682(4) Å and Z = 4 for 3 . Both monomeric units contain pentacoordinate metal ions in distorted square‐pyramidal arrangement. The structures of complexes 2 and 3 were also computed with DFT methods at B3LYP/LanL2DZ level and are in good agreement with the experimental values obtained from X‐ray analysis. The NPa charge distributions, HOMO–LUMO gaps, and dipole moments for 1 , 2 , and 3 were also reported. Natural bond orbital analyses were performed to reveal local charges and charge transfers in 1 , 2 , and 3 .  相似文献   
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Raif Usta  Eray Arslan 《PAMM》2014,14(1):191-192
A simple and concise mathematical model describing the deformation and the electrical behavior of a bi-morph piezoelectric curved sensor subjected to pure bending is developed. In particular, the influence of the couple moment on the electrical potential generated in the sensor is investigated and the results are presented in graphical form. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
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