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881.
Seventeen inorganic and organic anions, that normally are insufficiently separated via ion chromatography, were completely separated by the addition of an organic solvent to a solution of BGE combined with an adjustment of the apparent pH via CE in combination with indirect UV absorbance detection. Methanol, ethanol, and acetonitrile were examined for their utility in manipulating the selective separation of anions. Methanol and acetonitrile were better modifiers than ethanol at enhancing the resolution of anions comigrating in an aqueous solution of BGE. Methanol was selected as the modifier that provided the largest separation window that could achieve a complete separation of the target analytes. Via the use of methanol, manipulation of the selectivity between inorganic anions and that between inorganic and organic anions was enhanced, but the separation between organic anions remained difficult when only methanol was used. By varying the apparent pH of the BGE in the presence of 10% v/v methanol, however, the separation selectivity between organic anions was substantially improved. Eventually, 7 inorganic and 10 organic anions were simultaneously separated using BGE at a pH of 6.3 in the presence of 10% v/v methanol. 相似文献
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Kazuhiko Okitsu Yasuhiro Hayakawa Tomuo Yamaguchi Masashi Kumagawa Akira Hirata Syogo Fujiwara Yasunori Okano Nobuyuki Imaishi Shinichi Yoda Toshihiko Oida 《Crystal Research and Technology》1996,31(8):969-978
A mixing experiment of multicomponents melts was performed using a uniform temperature furnace in the Second International Microgravity Laboratories (IML-2) mission. Growth morphologies and Ga concentration profiles were analyzed for the samples with the compositional ratio of 0.5 In–0.5 Ga–1.0 Sb grown under microgravity and on earth. The sample with free surface grown under microgravity was nearly spherical in shape, except some parts with projections. Ga was dispersed homogeneously in the bulk because the mixing was enhanced by Marangoni convection due to the concentration gradient. On the other hand, the sample grown on earth was a double cylindrical shape with different diameters, and Ga concentration decreased from top to bottom, showing clearly the effect of gravity. Many needle crystals were formed in both space and earth samples due to rapid cooling. The average size of the needle crystals grown in space was larger than that of the earth sample. 相似文献
885.
An Inverse Problem of Determining Coefficients in a One-Dimensional Radiative Transport Equation 下载免费PDF全文
Nobuyuki Higashimori 《advances in applied mathematics and mechanics.》2014,6(4):515-522
We consider an inverse problem of determining unknown coefficients for a
one-dimensional analogue of radiative transport equation.
We show that some combination of the unknown coefficients can be uniquely determined
by giving pulse-like inputs at the boundary and observing the corresponding outputs.
Our result can be applied for determination of absorption and scattering properties of an
optically turbid medium if the radiative transport equation is appropriate for describing
the propagation of light in the medium. 相似文献