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31.
The third-order nonlinear optical (NLO) property of the α- and β- isomers of [Mo8O26]4? polyoxometallate ion were studied by DFT/TDDFT method. The second static hyperpolarisabilities, γiiii, γiijj and γmean were calculated by finite-field method as an extension of the usual DFT run, and the results suggest that without any ligands coordinated, the two isomer molecules in high symmetry own modestly large γ values (γmean ~5×10?32esu, 3×10?32esu, respectively), and the electronic properties of the two isomers were also studied by DFT method for the discussion of the origination of the NLO response, especially the unique effect of the molecular orbital ‘closed loops' on the NLO response. 相似文献
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Three-dimensional (3D) hierarchical porous TiO2/InVO4 nanocomposites were fabricated by loading TiO2 nanoparticles on the surface of porous InVO4 microspheres. X-ray diffractometer (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV–vis spectroscopy and photoluminescence spectroscopy (PL) were adopted to analyze the structure–property relationship of samples. The results show that the surface of as-prepared TiO2/InVO4 nanocomposites are composed of uniformly interconnected bi-phase nanocrystals, forming a close interface between these two components, which is favorable for the highly efficient interparticle electron transfer to achieve enhanced photocatalytic properties. However, the adsorption ability is decreased due to the loading of TiO2 nanoparticles on the surface of InVO4. Therefore, under the joint action of these factors, the TiO2/InVO4 nanocomposites achieve the best photocatalytic activity when the mole ratio of In:Ti reaches 4:1, and the visible-light photocatalytic activity is about as 3.3 times high as that of pure InVO4 without modification. 相似文献
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Joanna Znaleziona Pavlína Ginterová Jan Petr Peter Ondra Ivo Válka Juraj Ševčík Jan Chrastina Vítězslav Maier 《Analytica chimica acta》2015
Synthetic cannabinoids have gained popularity due to their easy accessibility and psychoactive effects. Furthermore, they cannot be detected in urine by routine drug monitoring. The wide range of active ingredients in analyzed matrices hinders the development of a standard analytical method for their determination. Moreover, their possible side effects are not well known which increases the danger. 相似文献
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Misa Hayashida Shinya Terauchi Toshiyuki Fujimoto 《Micron (Oxford, England : 1993)》2010,41(5):540-545
An automatic coarse-alignment method for a tilt series of rod-shaped specimen collected with a full angular range (from α = ?90° to +90°, α is the tilt angle of the specimen) is presented; this method is based on a cross-correlation method and uses the outline of the specimen shape. Both the rotational angle of the tilt axis and translational value of each image can be detected in the images without the use of markers. This method is performed on the basis of the assumption that the images taken at α = ?90° and α = + 90° are symmetric about the tilt axis. In this study, a carbon rod on which gold particles have been deposited is used as a test specimen for the demonstration. This method can be used as an automatic coarse-alignment method prior to the application of a highly accurate alignment method because the alignment procedure can be performed automatically except for the initial setup of some parameters. 相似文献
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Improved bi-accelerator derivative free with memory family for solving nonlinear equations 下载免费PDF全文
J. P. Jaiswal 《Journal of Applied Analysis & Computation》2016,6(1):196-206
The object of the present paper is to accelerate the $R$-order convergence of with memory derivative free family given by Lotfi et al. (2014) without adding any new evaluations. To achieve this goal one more iterative parameter is introduced, which is calculated with the help of Newton''s interpolatory polynomial. It is shown that the $R$-order convergence of the proposed scheme is increased from 12 to 14 without any extra evaluation. Smooth as well as non-smooth examples are presented to confirm theoretical result and significance of the new scheme. 相似文献
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《The Journal of chemical thermodynamics》2006,38(2):173-178
Metastable equilibrium solubilities and properties such as densities, conductivity, pH, refractive index, and viscosity of the solution were determined experimentally. According to the experimental data, the metastable equilibrium phase diagram was plotted. In the phase diagram, there are three invariant points, seven univariant curves, five fields of crystallization: Li2SO4 · H2O, K2SO4, Li2B4O7 · 3H2O, K2B4O7 · 4H2O, and K2SO4 · Li2SO4. The double salt K2SO4 · Li2SO4 was found in the quaternary system metastable equilibria. Lithium sulfate (Li2SO4) has the highest concentration and strong salting-out effects on other salts.Also, the relationship diagram between the properties and the ion concentration of solution was constructed. It can be seen from the relationship diagram that the equilibrium solution density values, viscosity values, and refractive index values are increased apparently with the rise of sulfate ion concentration, reaching the maximum values at eutonic point F3. Electrical conductivity values and pH values, however, fall down with the rise of ion concentration on the whole. 相似文献
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Rinda Hedwig Wahyu Setia Budi Syahrun Nur Abdulmadjid Marincan Pardede Maria Margaretha Suliyanti Tjung Jie Lie Davy Putra Kurniawan Koo Hendrik Kurniawan Kiichiro Kagawa May On Tjia 《Spectrochimica Acta Part B: Atomic Spectroscopy》2006,61(12):1285-1293
The applicability of spectrochemical analysis for liquid and powder samples of minute amount in the form of thin film was investigated using ultraviolet Nd-YAG laser (355 nm) and low-pressure ambient air. A variety of organic samples such as commercial black ink usually used for stamp pad, ginseng extract, human blood, liquid milk and ginseng powder was prepared as film deposited on the surface of an appropriate hard substrate such as copper plate or glass slide. It was demonstrated that in all cases studied, good quality spectra were obtained with very low background and free from undesirable contamination by the substrate elements, featuring ppm or even sub-ppm sensitivity and worthy of application for quantitative analysis of organic samples. The proper preparation of the films was found to be crucial in achieving the high quality spectra. It was further shown that much inferior results were obtained when the atmospheric-pressure (101 kPa) operating condition of laser-induced breakdown spectroscopy or the fundamental wavelength of the Nd-YAG laser was employed due to the excessive or improper laser ablation process. 相似文献
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