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161.
162.
Dip coated vacuum annealed zinc tin oxide thin films on soda lime silica glass have been deposited from the precursor sols containing zinc acetate dihydrate and tin (IV) chloride pentahydrate (Zn:Sn = 67:33, atomic ratio in percentage) in 2-methoxy ethanol by varying sol pH (0.85–5.5). Crystallinity, morphology, optical and photocatalytic properties of the films strongly depend on sol pH. Measurement of grazing incidence X-ray diffraction confirms the presence of hexagonal nano ZnO in the films derived from the sols of pH < 5.5. Film crystallinity deteriorates on increasing sol pH and the film deposited from the sol of pH 5.5 shows XRD amorphous but the selected area diffraction pattern and HRTEM image evidence the presence of nano Zn2SnO4 (size, 5–6 nm). Direct band gap energy of films increases on increasing sol pH. To visualize the film surface microstructure, FESEM study has been done and a rod-like surface feature is revealed in the film deposited from the sol of pH 2.85. A dependence of precursor sol pH on the photocatalytic activity of films towards degradation of Rhodamine 6G dye under UV (254 nm) irradiation is found and the highest decomposition rate constant, ‘k’ value is obtained from the film prepared from the sol of pH 5.5. The presence of zinc deficient nano Zn2SnO4 in the film may consider for generating the highest ‘k’ value. We also measure gelling time, viscosity of sols as well as UV and FTIR studies on the films and propose chemical reactions. 相似文献
163.
Sachindranath Paul Anil Kumar Barik Ray J. Butcher Susanta Kumar Kar 《Polyhedron》2000,19(28):2661-2666
Nickel(II) complexes of the tripodal ligand (MPz3tren) of the general formula [Ni(MPz3tren)]X2·nH2O (X=Cl, Br, NO3, ClO4 and BF4; n=0 for Cl and Br; n=0.5 for NO3, ClO4 and BF4) have been prepared by template methodology and characterised by elemental analyses, magnetic susceptibility and conductivity measurements at RT, IR and electronic spectra. The molar conductivities measured in MeOH for all the complexes show them to be 1:2 electrolytes. The hexadentate character of the ligand in all the complexes is inferred from IR spectral studies. The electronic spectra in solid state and in MeOH solution suggest octahedral geometry for all the complexes. The structure of [Ni(MPz3tren)](BF4)2·0.5H2O has been determined by single-crystal X-ray diffraction studies (monoclinic, c2/c). Nickel(II) is in a trigonal antiprismatic N6 donor environment and the crystal structure is stabilised by a network of strong H-bonding. 相似文献
164.
Anup Paul Kristina Radinovi Susanta Hazra Duan Mladenovi Biljana ljuki Rais Ahmad Khan Maria Ftima C. Guedes da Silva Armando J. L. Pombeiro 《Molecules (Basel, Switzerland)》2022,27(21)
The new 3D coordination polymer (CP) [Mn(L)(HCOO)]n (Mn-CP) [L = 4-(pyridin-4-ylcarbamoyl)benzoate] was synthesised via a hydrothermal reaction using the pyridyl amide functionalized benzoic acid HL. It was characterized by elemental, FT-IR spectroscopy, single-crystal and powder X-ray diffraction (PXRD) analyses. Its structural features were disclosed by single-crystal X-ray diffraction analysis, which revealed a 3D structure with the monoclinic space group P21/c. Its performance as an electrocatalyst for oxygen reduction (ORR), oxygen evolution (OER), and hydrogen evolution (HER) reactions was tested in both acidic (0.5 M H2SO4) and alkaline (0.1 M KOH) media. A distinct reduction peak was observed at 0.53 V vs. RHE in 0.1 M KOH, which corresponds to the oxygen reduction, thus clearly demonstrating the material’s activity for the ORR. Tafel analysis revealed a Tafel slope of 101 mV dec−1 with mixed kinetics of 2e− and 4e− pathways indicated by the Koutecky–Levich analysis. Conversely, the ORR peak was not present in 0.5 M H2SO4 indicating no activity of Mn-CP for this reaction in acidic media. In addition, Mn-CP demonstrated a noteworthy activity toward OER and HER in acidic media, in contrast to what was observed in 0.1 M KOH. 相似文献
165.
Journal of Radioanalytical and Nuclear Chemistry - Vortex assisted in situ ionic liquid dispersive liquid–liquid microextraction method was developed for extraction of U(VI) from aqueous... 相似文献
166.
167.
Sirsendu Das Adhikary Ambarish Mondal Hemanta K. Kisan Christopher W. Bielawski Joydev Dinda 《应用有机金属化学》2020,34(2):e5335
A series of silver(I) and gold(I) carbene complexes of the type [M(L)(2,2′-bipyridine)][PF6] (L = 1-benzyl-3-(2-pyridylmethyl)benzimidazolylidene; M = Ag ( 1 ); M = Au ( 3 )) and [M(L)(carbazole)] (M = Ag ( 2 ); M = Au ( 4 )) were synthesized and analyzed using a range of spectroscopic and crystallographic techniques. Inspection of the solid-state structures of 1 , 2 and 4 revealed a number of intermolecular noncovalent interactions. In the solid-state structure adopted by 1 , π–π and Ag–Ag interactions directed the complexes to orient in a head-to-tail fashion. The photophysical properties were found to be influenced by the ancillary ligands in solution as well as in the solid-state. Calculations were performed to support the aforementioned structural and optoelectronic assignments. 相似文献
168.
Dinda Soumitra Sarkar Koushik Panda Bikash Kumar Pramanik Kausikisankar Ganguly Sanjib 《Transition Metal Chemistry》2022,47(1):31-38
Transition Metal Chemistry - By using a multifunctional diarylazooxime ligand LNOH 1, incorporating electron deficient azo chromophore in conjunction with a pendant π-electron-rich naphthyl... 相似文献
169.
We report the measurement of temperature-dependent dielectric parameters in some binary liquid crystal mixtures comprising of a hockey-stick-shaped mesogen 4-(3-decyloxyphenyliminomethyl) phenyl-4-decyloxycinnamate (SF7) and calamitic compound 4′-octyloxy-4-cyanobiphenyl (8OCB). All the investigated mixtures possess a large positive dielectric anisotropy (Δε), although a noticeable reduction has been found by increasing the diverse-shaped dopant concentration. Investigation on the pretransitional behavior in the vicinity of isotropic to nematic (I–N) phase transition suggesting a tricritical character for all the studied mixtures. Parameterization of dielectric permittivity close to the nematic to smectic-A (N–Sm-A) phase transition exhibits non-universal values of the critical exponents describing a second-order nature of the transition. Systematic variation of critical exponents against dopant concentration and McMillan ratio reveals a well consistency with those obtained from the high-resolution optical birefringence measurements. 相似文献
170.
E. Tchomgo Felenou P. Tchofo Dinda C.M. Ngabireng K. Nakkeeran 《Physics letters. A》2013,377(10-11):770-777
We consider optical waveguides in which light pulses may execute complex dynamical behaviors including translational motions accompanied with strong internal vibrations. Such systems necessarily generate various types of collective motion, in which each collective mode is describable by a collective coordinate. We present a novel projection operator formalism for deriving the equations of motion of the collective coordinates and coupled fields. This formalism is built up by treating separately the dynamics of the pulse phase and that of its amplitude, that is, by using two distinct projection operators (one for the amplitude, and the other one for the phase). This new pair of operators, which we call reduced projection operators, has as main virtue of having dimension reduced by half as compared to that of the conventional operators that includes both pulse amplitude and phase together. The main interest of the reduced projection operators lies in the ease with which the equations of motion are derived when compared with the amount of algebra needed to obtain the same equations from the conventional projection operators. We provide examples of concrete situations that illustrate the effectiveness of the collective-coordinate approach based on the reduced projection operators. 相似文献