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41.
The coordination behaviour of the novel ligand, HMPz4Cy, is reported, together with solid state isolation of its diamagnetic cobalt(III) complexes, [Co(MPz4Cy)2]X · nH2O (X = Cl, Br, NO3, ClO4 and BF4). I.r. and 1H-n.m.r. data for the free ligand and its CoIII complexes confirm that the ligand, HMPz4Cy, acts as a uninegative anion with NNS tridentate function via the pyrazolyl nitrogen (tertiary), azomethine nitrogen and thiol sulphur. Electronic spectra (both solid and solution) are commensurate with a distorted octahedral environment for the reported CoIII species. Cyclic voltammograms of CoIII complexes indicate a quasireversible Co+3/Co+2 couple. X-ray crystallography of a representative species, [Co(MPz4Cy)2]Cl · 2.75H2O (C2, monoclinic), has shown unambiguously that the two ligands are orthogonally coordinated to the central CoIII ion with both the thiolato sulphurs and both pyrazolyl nitrogen atoms in cis positions.  相似文献   
42.
Nano-composite polymer electrolytes containing poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP), ammonium tetrafluoroborate (NH4BF4), and nano-size fumed silica (SiO2) have been prepared and characterized by complex impedance spectroscopy. Ionic conductivity of polymer has been found to increase with the addition of NH4BF4, and a maximum conductivity of 3.62 × 10?6 S/cm has been obtained at 30 wt% NH4BF4. The formation of ion aggregates at high concentration of salt has been explained by Bjerrum’s law and mass action considerations. The conductivity of polymer electrolytes has been increased by three orders of magnitude (10?6 to 10?3 S/cm) with the addition of plasticizer, and a maximum conductivity of 1.10 × 10?3 S/cm has been observed at 80 wt% DMA. An increase in conductivity with the addition of nano-size fumed silica is attributed due to the formation of space-charge layers. A maximum conductivity of 7.20 × 10?3 S/cm has been observed for plasticized nano-composite polymer electrolytes at 3 wt% SiO2. X-ray diffraction analysis of polymer electrolyte system was also carried out. A small change in conductivity of nano-composite polymer electrolytes observed over the 30–130 °C temperature range and for a period of 30 days is also desirable for their use in various applications.  相似文献   
43.
Phytochemical investigation of the acetone extract of the aerial parts of Anisochilus verticillatus afforded a new 8,9-secopimarane diterpene (1), two new isopimarane diterpenes (2, 3) and the known ursolic acid (4), α-amyrin (5), β-amyrin (6), stigmast-5-en-3-one (7) and hydroxychavicol (8). Structures of the new compounds were elucidated with the help of 1D and 2D nuclear magnetic resonance spectroscopic data, and single crystal X-ray crystallography of compound 3. Compounds 2 and 8 inhibited Mycobacterium tuberculosis H37Ra with an IC50 of 11.3 (IC90 of 20.0 μg/mL) and 12.5 μg/mL, respectively. Correspondingly, molecular docking studies with Extra Precision Glide revealed a correlation between score and biological activity for these compounds to describe the molecular basis for the most significant SAR results.  相似文献   
44.
Isotopic dependence of the fusion dynamics is studied by analyzing the collision of a large number of isotopes of Ca and Ni with 0.6 N/Z 2. This study, which results from the Skyrme energy density formalism, reveals that the addition of neutrons favors fusion of reacting partners, whereas the reverse happens with the removal of neutrons. The fusion barrier heights and positions follow a non-linear second-order dependence on ( -1 ), whereas fusion cross-sections can be parameterized by a straight line.-1  相似文献   
45.
Zwitterionic imidazolium sulfonates are excellent catalysts for stereoselective aza-Henry reaction under solvent-free conditions. The major syn-β-nitroamine is obtained in high yields. This three-component condensation reaction catalyzed by zwitterionic-type molten salt deserves attention in its own right as a useful method.  相似文献   
46.
Two-neutrino ββ decay matrix elements and half-life of 48Ca are calculated after including neutron-proton pairing correlations in projected Hartree-Fock-Bogoliubov (PHFB) formalism. The GT matrix elements in 2νββ decay are reduced due to broader smearing of Fermi surfaces. Half-life results for 2νββ decay of 48Ca with np pairing are better than without pairing.  相似文献   
47.
Microwave characterization of SrCo x Ti x Fe(12?2x)O19 (x = 0.0, 0.2, 0.3, 0.5, 0.6, 0.7, 1.0) ferrites has been studied as a function of frequency, substitution and thickness, and static electrical current density-electric field characteristics have been investigated as a function of substitution. Microwave characteristics have been measured using power meter in the rectangular slotted waveguide and current density is measured using electrometer. The microwave absorption is evaluated using the standard available model. The results depict ?11.57 dB reflection loss at 10.38 GHz in composition x = 0.6. The electrical current density decreases at lower substitution and increases at higher substitution. The substitution of Co2+ and Ti4+ ions causes enhancement of electromagnetic and static electrical properties.  相似文献   
48.
A new series of 4-(4-(1-benzyl-1H-1,2,3-triazol-4-yl)-1-phenyl-1H-pyrazol-3-yl)quinoline ( 6a-t ) have been synthesized by a click reaction of 4-(4-ethynyl-1-phenyl-1H-pyrazol-3-yl)quinoline ( 4a-d ) with a substituted benzyl azide ( 5a-e ). The starting alkyne derivatives 4a-d are obtained from Bestmann-Ohira reaction of 1-phenyl-3-(quinolin-4-yl)-1H-pyrazole-4-carbaldehyde and dimethyl(1-diazo-2-oxopropyl)phosphonate. The newly synthesized compounds are screened against M. tuberculosis H37Ra dormant and active, Escherichia coli, Pseudomonas fluorescence, Staphylococcus aureus and Bacillus subtilis strains at 30 μg/mL concentration. Most of the screened compounds showed good to moderate antibacterial activity against S. aureus, B. subtilis, and Mycobacterium tuberculosis H37Ra strains. The synthesized derivatives of quinolinyl-pyrazole-4-carbaldehyde and quinolinyl-pyrazole-4-ethyne reportd good to moderate activity against both strains of M. tuberculosis H37Ra. Ten derivatives of quinolinyl-pyrazole presented good activity against B. subtilis. These results suggested that further optimization and development of quinolinyl-pyrazolyl-1,2,3-triazole moeity could serve as lead compounds for antimycobacterial activity.  相似文献   
49.
Molecular Diversity - Herein, we identified a potent lead compound RRA2, within a series of 54 derivatives of 1,2,4-triazolethiols (exhibit good potency as an anti-mycobacterial agents) against...  相似文献   
50.
We study the dynamics of a coupled two-channel ASEP in which intra-channel transition rates are dependent on the configuration of neighboring channel. The binding constant kk, which signifies the ratio of inter-channel transition rates, is introduced and the symmetric and asymmetric coupling conditions are analyzed for different values of kk. The vertical cluster mean-field theory is used to study the system behavior exactly in strong coupling conditions and approximately in intermediate coupling conditions. Additionally, the consequences of particular dynamics such as totally asymmetric simple exclusion process (TASEP), partially asymmetric simple exclusion process (PASEP) and symmetric simple exclusion process (SSEP) in either one or both channels are investigated. It is found that the transition rates have a significant influence on both the qualitative and quantitative nature of the phase diagrams. The mathematical computation shows how the number of phases varies from 3 via 6 to 7 under different environments. Interestingly, in the fully asymmetric coupling case, the results are found to be independent of the magnitude of non-zero vertical transition rate. Our theoretical arguments are in well agreement with extensively performed Monte-Carlo simulation results.  相似文献   
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