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The synthesis and crystal structure of pyridine-3-carbaldehyde-N-ethylthiosemicarbazone (3-pytscH-NHEt) 1, and its CuI complex of stoichiometry, [CuCl(3-pytscH-NHEt)(PPh3)2] 2, studied using single crystal X-ray crystallography, are reported in this paper. Crystal data: 1, monoclinic, P21/n, a?=?6.6322(3), b?=?21.1200(8), c?=?7.2989(3) Å; β?=?91.883(4), T?=?173(2), R factor?=?0.0457; 2: triclinic, P-1, a?=?19.3600(5), b?=?20.6241(6), c?=?23.8015(6) Å,α?=?92.647(2), β?=?104.388(2), γ?=?114.377(3), R factor?=?0.0662. The thio-ligand, as a neutral entity, is coordinating to Cu through its S donor atom in complex 2. It has exhibited an unusual feature of forming four independent molecules (A, B, C, D) in the unit cell, with minor differences in the bond angles / distances / torsion angles. The geometry of each molecule of 2 is distorted tetrahedral. Crystal packing, as well as Infrared, electronic absorption and proton NMR spectroscopic studies, are also reported. Copper compound 2 represents the first example of a structurally studied copper coordination compound of 3-pyridyl based thiosemicarbazones.
Graphical AbstractCopper(I) chloride with pyridine-3-carbaldehyde-N-ethylthiosemicarbazone and PPh3 in CH3CN yielded a copper compound, 2 (Green-Cl, blue-N; aqua-Cu, orange-S, magneta-P).
Surface of powdered LaNi5 intermetallic compound has been modified by active particle coverage with electroless nickel (Ni-P). The electrode degradation process in 6 M KOH solution has been tested across 70 charge/discharge cycles at −0.5 C/+0.5 C rates. It has been established that after approx. 25–35 initial cycles, the electrode degradation process fulfills first order chemical reaction kinetics law: logarithm of discharge capacity linearly decreases with cycle number. The rate constant for the Ni-P protected material is over 20 % lower than that of as received one. The surface modification also improves the alloy hydrogenation kinetics: exchange current densities of H2O/H2 system are generally greater for modified material and, contrary to uncovered material, do not practically decrease with long-lasting cycling.
相似文献Characterization of ion transport property in dry solid polymer electrolyte (SPE) films: [PEO: Zn(CF3SO3)2] in different salt wt% ratio has been reported. SPE films have been prepared by a hot-press casting procedure. Salt concentration dependent conductivity study at room temperature identified SPE film: [90PEO: 10 Zn(CF3SO3)2] as optimum conducting composition (OCC) with σ rt ~ 1.09 × 10−6 S/cm which is approximately three orders of magnitude higher than that of pure PEO host (σ rt ~ 3.20 × 10−9 S/cm). The reason attributed for σ rt enhancement has been the increase in degree of amorphous phase in polymeric host after salt complexation. This has been confirmed by X-ray diffraction (XRD), Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), and polarized optical microscopy (POM) analysis. To evaluate the usefulness of SPE OCC film in all-solid-state-battery applications, ion transport property has been characterized in terms of basic ionic parameters viz. ionic conductivity (σ) and total ionic (t ion)/cation (t +) transport numbers. Mechanism of ion transport has been explained by temperature dependent conductivity measurements and the activation energy (E a) has been computed by least square linear fitting of “log σ − 1/T” Arrhenius plot.
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