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1.
Summary Compounds of the type PdL2X2 (L=1-methylimidazole, 1-vinylimidazole, 1-n-butylimidazole, 1,2-dimethylimidazole, 1-vinyl-2-methylimidazole, 1,2-dimethyl-5-nitroimidazole, 2-isopropyl-4(5)-nitroimidazole and 2-methyl-4(5)-nitro-imidazole; X=Cl or Br) are obtained by treating PdX2 (1 mole) with solutions of the ligands L (2 moles). An excess of L gives PdL4X2 complexes (L=1-methylimidazole, 1-vinylimidazole, 1,2-dimethylimidazole and 1-vinyl-2-methylimidazole). The compounds were characterized by chemical analyses, molar conductivity measurements and i.r. spectra.  相似文献   
2.
Structural Chemistry - A Correction to this paper has been published: https://doi.org/10.1007/s11224-021-01788-w  相似文献   
3.
The main objective of this study is to provide an insight into the interactions involved during adsorption of the alcohols on β-CD composite nanostructured membrane. Interactions between β-cyclodextrin (β-CD) and alcohols (methanol, ethanol and butanol) are studied using the QM/MM method. Magnitude of interaction energies show that the alcohols are adsorbed on the membrane. In addition, the thermochemical analysis suggests that the formation of these host-guest complexes is enthalpy driven.  相似文献   
4.
Structural Chemistry - Density functional theory (DFT) has been employed to study the structure, stability and reactivity of curcumin and some of its important analogues by computing HOMO-LUMO...  相似文献   
5.
Various 1,5‐benzodiazepine and quinoxaline derivatives have been synthesized in water with excellent yields using a catalytic amount of indium chloride at room temperature. This synthetic protocol is nontoxic, safe, and environmentally benign.  相似文献   
6.
In this article we introduce the sequence spaces cI(M),c0I(M),mI(M) and m0I(M) using the Orlicz function M.We study some of the properties like solid,symmetric,sequence algebra,etc and prove some inclusion relations.  相似文献   
7.
We used variationally improved perturbation theory (VIPT) in calculating the slope and curvature of Isgur-Wise (I-W) function with the Cornell potential −$ \frac{{4\alpha _s }} {{3r}} $ \frac{{4\alpha _s }} {{3r}} +br + c instead of the usual stationary state perturbation theory as done earlier. We used −(4α s /3r), i.e. the Coulombic potential, as the parent and the linear one, i.e. br+c as the perturbed potential in the theory and calculated the slope and curvature of Isgur-Wise function including three states in the summation involved in the first-order correction to wave function in the method.  相似文献   
8.
Polypyrrole (PPy) nanofibers have been synthesized by interfacial polymerization method and irradiated with 160?MeV Ni12+ ions under vacuum with fluences in the range of 1010–1012?ions/cm2. High-resolution transmission electron microscopy results show that upon swift heavy ion (SHI) irradiation the PPy nanofibers become denser. The crystallinity of PPy nanofibers increases upon SHI irradiation, while their d-spacing decreases. Upon SHI irradiation, the polaron absorption band gets red-shifted indicating reduction in the optical band gap energy of the irradiated PPy nanofibers. The indirect optical band gap energy is decreased as compared to corresponding direct optical band gap energy. The number of carbon atoms per conjugation length (N) and carbon atoms per cluster (M) of the SHI-irradiated PPy nanofibers increase with increasing the irradiation fluence. Fourier transform infrared spectra reveal the enhancement in intensity of some characteristic vibration bands upon SHI irradiation. The thermal stability of the PPy nanofibers is enhanced on SHI irradiation. The charge carriers in both pristine and irradiated PPy nanofibers follow the correlated barrier hopping mechanism. Scaling of ac conductivity reveals that the conduction mechanism is independent of the SHI irradiation fluence.  相似文献   
9.
Iron and its binary oxides are meticulously exploited for environmental remediations. However, only limited studies have been carried out on the degradation of industrial organics by advanced oxidation process. In this study, iron oxide, cobalt oxide, and iron–cobalt binary oxides were synthesized by a modified hydrothermal method as heterogeneous Fenton-like catalysts for the removal of methylene blue (MB) from wastewaters. The oxide nanostructures were characterized by different analytical techniques. Studying the effects of various parameters such as catalyst dose, MB concentration, and H2O2 concentration, the reaction conditions were optimized to enhance the removal of MB dye. The results revealed that α-Fe2O3–Co3O4 shows much higher activity than both Co3O4 and α-Fe2O3 for the degradation of MB at room temperature and beyond. The binary α-Fe2O3–Co3O4 shows degradation efficiency of 96.4% at 65 °C within 60 min. Furthermore, the binary α-Fe2O3–Co3O4 catalyst retains its activity for up to four successive cycles. A probable mechanism is also proposed, involving the generation of ‧OH radical as well as Fe2+/Fe3+ or Co2+/Co3+ redox couple of the binary α-Fe2O3–Co3O4 catalyst.  相似文献   
10.
This study focuses on the electrical characteristics of a strongly polar nematic liquid crystal, Hexyloxy-cyanobiphenyl (6OCB), doped with a low concentration (2% by weight) of citrate buffer stabilised gold nanoparticles (GNPs) at low frequencies between 20 Hz and 35 MHz. The doped samples have lower values of nematic–isotropic transition temperature, permittivity (both parallel and perpendicular to the field direction) and dielectric anisotropy; however, relaxation time and activation energy were increased. The observed results could be explained on the basis of weakly anisotropic nature of GNPs and a local rearrangement of liquid crystal molecules surrounding the nanoparticles. Moreover, a complimentary suggestion on a possible change in the dipole–dipole correlation is made to explain the difference in changes (qualitative and quantitative) observed for permittivity of the host nematic liquid crystal doped with GNP. Temperature dependent dielectric relaxation studies indicate an increase in viscosity and potential barrier; and hence a change in strength of inter-molecular and intra-molecular interactions is suggested.  相似文献   
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