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31.
W. L. Scoville 《Fresenius' Journal of Analytical Chemistry》1912,51(12):780
Ohne Zusammenfassung 相似文献
32.
A method for the determination of the chromatographically accessible area of a reversed-phase column similar to the method of H?gglund and St?hlberg [J. Chromatogr. A 761 (1997) 13] is applied to a column containing a polystyrene-divinylbenzene resin. Its theoretical basis is Gouy-Chapman theory in combination with an electrostatically modified linear adsorption isotherm. The surface area value determined for the resin, 96 m2/g, is much less than the reported surface area value, 400 m2/g, determined by N2 sorptometry and application of Branauer-Emmett-Teller (BET) theory. The method also provides a value for the number of moles of native anionic sites present on the column. 相似文献
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A solvent-free mechanochemical route for the preparation of poly(2,5-dimethoxyaniline) hydrochloride nanostructures is developed
and reported in the article. High conductivity, good crystallinity, and nanostructured morphology are observed for the prepared
polymer. This polymeric powder is utilized as a cathode material in hybrid supercapacitor and its electrochemical performance
is evaluated and discussed in this short report. The maximum specific capacitance of the poly(2,5-dimethoxyaniline) hydrochloride/activated
carbon hybrid supercapacitor is found to be 125 F g−1 at 1 mA cm−2 current density. The cell delivers a specific energy as high as 50 Wh kg−1 at a specific power of 97 W kg−1 and also exhibits an excellent cycle performance with more than 99% coulombic efficiency and the maintenance of 85% of its
initial capacitance after 1,000 cycles. 相似文献
35.
Single crystals of benzophenone-2-furoyl hydrazone are grown by slow evaporation solution growth technique from ethanol at room temperature. It belongs to monoclinic system with the space group P21/c and the cell parameters are, a = 6.1631(3) Å, b = 13.1397(8) Å, c = 18.0030(11) Å and V = 1457.72(14) Å3. NMR spectral studies reveal the structure and powder XRD indicates the crystallinity of the specimen. The characteristic functional groups present in the molecule are confirmed by Fourier transform infrared spectroscopy. The crystals are transparent in the visible region having a lower optical cut-off at ∼406 nm and the band gap energies are estimated by the application of Kubelka–Munk algorithm. Thermal analysis by TG/DTA indicates the stability of the material. The scanning electron microscopy studies reveal the surface morphology of the as-grown crystal. Theoretical calculations were performed using Hartree–Fock method with 6-31G(d,p) as the basis set for to derive the optimized geometry, dipole moment and first-order molecular hyperpolarizability (β) values. 相似文献
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The effect of dopant cesium (Cs(I)) over a concentration range from 1 to 10 mol% on the growth process, morphology, thermal and optical properties of tri(thiourea)zinc(II) sulfate (ZTS) single crystals grown by slow evaporation solution growth technique has been investigated. Incorporation of Cs(I) into the crystal lattice was well confirmed by energy dispersive X-ray spectroscopy (EDS). The lattice parameters of the as-grown crystals were obtained by single crystal X-ray diffraction analysis. The reduction in the intensities observed in powder X-ray diffraction patterns of doped specimen and slight shifts in vibrational frequencies in fourier transform infrared spectra (FT-IR) indicate the lattice stress as a result of doping. Thermal studies reveal the purity of the material and no decomposition is observed up to the melting point. High transmittance is observed in the visible region and the cut-off λ is ~280 nm. The surface morphology of the as-grown specimens was studied by scanning electron microscopy (SEM). The second harmonic generation (SHG) efficiency of the host crystal is enhanced greatly in the presence of high concentrations of the dopant. 相似文献