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41.
A new chloride bridged polymeric Cu(II) complex, [Cu(HL)(μ-Cl).H2O]n, 1, (H2L = 2,4-dichloro-6-{[(2-hydroxyethyl)imino]methyl}phenol) has been synthesized and characterized by elemental-spectral analysis, crystal structure analysis and photoluminescence measurements. The Copper(II) atom is five-coordinate in a slightly distorted square-pyramidal geometry (τ = 0.085), with one N and two O atoms of the Schiff base ligand and one Cl atom defining the basal plane and a symmetry-related Cl atom occupying the apical position. The bridging Cl atom lies in apical position for one Cu(II) ion and basal for the other, and it makes this structural arrangement unusual. The linked moieties form polymeric zigzag chains running along the c axis. This zigzag chains connect each other with intramolecular and intermolecular O–H···O hydrogen bonds, which form 3D structure through π?π interactions. Furthermore, the photoluminescence properties of H2L and 1 were investigated, they exhibit unique bright green visible emissions in the solid state, under the excitation of 349 nm UV light. The strong luminescence emission of them makes 1 a potentially useful photoactive material in photo-physical chemistry.  相似文献   
42.
A new electrically conducting composite film from polypyrrole and 4,4′-(hexafluoroisopropylidene)-bis(phthalic anhydride)-based polyimide was prepared. Pyrrole and the dopant ion can easily penetrate through the polyimide substrate and electropolymerize on the platinum (Pt) electrode due to the swelling of the polyimide on the metal electrode. The electrochemical properties of polypyrrole-polyimide (PPy/PI) composite films have been investigated by using cyclic voltammetry. The PPy/PI composite film is suitable for use as the electroactive material owing to its stable and controllable electrochemical properties. The electrical conductivity of composites falls in the range 0.0035–15 S/cm. Scanning electron micrograph, FTIR, and thermal studies indicate that PPy and PI form a homogeneous material rather than a simple mixture. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 3009–3016, 1997  相似文献   
43.
A new copper complex trans-Dichlorobis[4-methoxypyridine]copper(II) (1) was synthesized and its crystal structure determined by X-ray diffraction. The close Cu···Cl contacts between the molecular units form bi-bridged dimers. The Copper(II) ion completes its 4 + 2 coordination via interaction with the Cu···Cl close contact. The complex has a polymeric structure of infinite one-dimensional (1D) bi-bridged chains, consisting of six-coordinate copper(II) units. C–H···C l intermolecular interaction connect the 1D-chains in the structure of 1 which form to 3D structure. The π ··· π interactions between the aromatic rings are also observed in the hydrogen bonded assembly of 1.  相似文献   
44.
Journal of Solid State Electrochemistry - Magnetite-carbon nanocomposite was grown in situ on nickel foam by a novel auto-combustion method, and it was investigated for application as a...  相似文献   
45.
Heteroarm H‐shaped terpolymers, (polystyrene)(poly(methyl methacrylate))‐ poly(tert‐butyl acrylate)‐(polystyrene)(poly(methyl methacrylate)), (PS)(PMMA)‐PtBA‐(PMMA)(PS), and, (PS)(PMMA)‐poly(ethylene glycol)(PEG)‐(PMMA)(PS), through click reaction strategy between PS‐PMMA copolymer (as side chains) with an alkyne functional group at the junction point and diazide end‐functionalized PtBA or PEG (as a main chain). PS‐PMMA with alkyne functional group was prepared by sequential living radical polymerizations such as the nitroxide mediated (NMP) and the metal mediated‐living radical polymerization (ATRP) routes. The obtained H‐shaped polymers were characterized by using 1H‐NMR, GPC, DSC, and AFM measurements. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1055–1065, 2007  相似文献   
46.
During the periods of 1997–1998, macroalgae, sea snail, mussel, fish and sediment samples were collected from different stations at Turkish Black Sea coast in order to determine activity levels of 137Cs radionuclide. 137Cs activity in the tested algae species and in soft parts of mussel and sea snail, were found to be below the lower limit of detection. On the other hand, the 137Cs concentration in muscle tissue of the sea snail samples were found from 6±2 to 19±7 Bq·kg–1 dry weight. The range of the 137Cs concentration in anchovy fish muscles were found between 4±2 – 10±5 Bq·kg–1 dry weight. The 137Cs concentration in the whiting fish muscle was found below the lower limit of detection. However, this activity found in shad fish muscle to be 25±10 Bq·kg–1 dry weight. The concentrationsof the 137Cs activity in the sediment samples proved that the eastern region of the Black Sea was affected by Chernobyl at a very high degree compared with the western part. The measured 238U, 232Th and 40K concentrations in sediment samples are within the range of the cited values in the previous works at the Turkish Black Sea coast.  相似文献   
47.
Well‐defined linear furan‐protected maleimide‐terminated poly(ethylene glycol) (PEG‐MI), tetramethylpiperidine‐1‐oxyl‐terminated poly(ε‐caprolactone) (PCL‐TEMPO), and azide‐terminated polystyrene (PS‐N3) or ‐poly(N‐butyl oxanorbornene imide) (PONB‐N3) were ligated to an orthogonally functionalized core ( 1 ) in a two‐step reaction mode through triple click reactions. In a first step, Diels–Alder click reaction of PEG‐MI with 1 was performed in toluene at 110 °C for 24 h to afford α‐alkyne‐α‐bromide‐terminated PEG (PEG‐alkyne/Br). As a second step, this precursor was subsequently ligated with the PCL‐TEMPO and PS‐N3 or PONB‐N3 in N,N‐dimethylformamide at room temperature for 12 h catalyzed by Cu(0)/Cu(I) through copper‐catalyzed azide‐alkyne cycloaddition and nitroxide radical coupling click reactions, yield resulting ABC miktoarm star polymers in a one‐pot mode. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   
48.
The microbial free single crystals of α and γ glycine were grown from gel at room temperature in a new chemical route. These crystals showed a superior quality than the solution grown crystals. The metastable α-form and the stable γ-form of glycine were crystallized in silica gel by solubility reduction method. The form of crystallization is confirmed by single crystal and powder X-ray diffraction analyses. The crystals of α and γ glycine were found to crystallize in monoclinic and hexagonal crystal systems, respectively. For analyzing the functional group and thermal stability of α and γ glycine crystals, spectroscopic and thermal analyses have been carried out. The dielectric studies were performed to find the dielectric constant of the grown crystals and the results are discussed. Second harmonic generation efficiency of the crystal was measured by Kurtz’s powder method using Nd:YAG laser and it was found to be 2.68 times that of potassium dihydrogen phosphate crystals.  相似文献   
49.
Raman and resonance-Raman spectra of the I?3 ion isolated within CsI crystals have been studied using 647 nm and 488 nm exciting radiation. Sample temperatures between 300 and 20 K have been used. Eleven overtones of the symmetric stretching mode (nν1) have been observed in the resonance-Raman spectrum excited by the 488 nm Ar+ laser line. Bands centred at 153, 170, 264 and 304 cm?1 have been assigned as ν3, 2ν2, ν13 and 2ν3+) respectively. The remaining structure between the nν1 lines has been assigned as due to combinations of these lines with the lattice vibrations of the CsI crystal.  相似文献   
50.
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