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81.
Delenclos S. Kolinsky C. Longuemart S. Hadj Sahraoui A. Buisine J. M. 《Journal of Thermal Analysis and Calorimetry》2002,70(2):549-558
The photopyroelectric (PPE) method is proposed as a sensitive technique to study a binary mixture of liquid crystals in a
contact preparation. The photothermal signal is generated while scanning the contact preparation. The crystal-smectic A, smectic
A-nematic, and nematic-isotropic interphase boundaries are detected. The displacement of these boundaries due to the variation
of the temperature is monitored. The study of these displacements allows us to draw the complete temperature-concentration
phase diagram of a binary mixtures.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
82.
The adsorption of complexes formed by sodium, potassium, and rubidium cations with macrobicyclic ligand (kryptofix 222 with C18H36N2O6 composition) is studied as a function of the ligand concentration on a stationary mercury drop in 0.1 M solutions of corresponding sulfates and chlorides by using the differential capacitance technique. Based on the model of two parallel capacitors supplemented by the Frumkin isotherm, the adsorption parameters of studied cryptates are estimated by using the regression analysis technique. Differential capacitance curves calculated with the parameters found are compared with experimental data. The comparison of the found adsorption parameters makes it possible to reveal the effects of the nature of included cations and specifically adsorbed supporting-electrolyte anions on the adsorption behavior of cryptates under study.__________Translated from Elektrokhimiya, Vol. 41, No. 4, 2005, pp. 475–481.Original Russian Text Copyright © 2005 by Stenina, Sviridova. 相似文献
83.
E. L. Anderson M. M. Thomason H. T. Mayfield W. Bertsch 《Journal of separation science》1979,2(6):335-342
A versatile two-dimensional gas chromatograph is described, consisting of 2 separate ovens, one intermediate trap, an auxiliary inlet, and the necessary hardware to effect off-line switching according to the principle of Deans. The unit has been designed for use with high resolution glass capillary columns. The performance of individual instrumental components was critically evaluated. Results showed that low dead volume glass to metal connections were required in the manifold and detector lines to minimize extra-column effects. The mass of the intermediate trap must be low to allow rapid heating. Operational parameters are discussed and examples of some applications are shown. 相似文献
84.
碘溴化银乳剂薄片颗粒的潜影分散与碘离子在颗粒中的分布有关。本文用交叉光楔曝光技术测定了由次潜影造成的潜影分散,并根据所测出的潜影分散度和乳剂的表面感光度,对内、表敏的分布作了分析。结果表明,碘离子分布在颗粒边缘的乳剂,其表面潜影分散度要比碘离子均匀分布的颗粒更甚,后者且表现出内、表敏度竞争的现象。 相似文献
85.
A delayed coincidence method, time-interval analysis (TIA), has been applied to successive – decay events on the millisecond time-scale. Such decay events are part of the 220Rn216Po (T1/2 145 ms) (Th-series) and 219Rn215Po (T1/2 1.78 ms) (Ac-series). By using TIA in addition to measurement of 226Ra (U-series) from -spectrometry by liquid scintillation counting (LSC), two natural decay series could be identified and separated. The TIA detection efficiency was improved by using the pulse-shape discrimination technique (PSD) to reject -pulses, by solvent extraction of Ra combined with simple chemical separation, and by purging the scintillation solution with dry N2 gas. The U- and Th-series together with the Ac-series were determined, respectively, from alpha spectra and TIA carried out immediately after Ra-extraction. Using the 221Fr217At (T1/2 32.3 ms) decay process as a tracer, overall yields were estimated from application of TIA to the 225Ra (Np-decay series) at the time of maximum growth. The present method has proven useful for simultaneous determination of three radioactive decay series in environmental samples. 相似文献
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88.
IntroductionMicellarelectrokineticchromatography (MEKC)wasinventedtoextendtheutilityofcapillaryelectrophoresis(CE)andpermittedtheseparationandanalysisofneutralcompounds .ButjustlikeothermodesofCE ,MEKCarehamperedbythelowconcentrationsensitivityoftheultra … 相似文献
89.
Some of the blending interpolation methods (which) stated by a convex combination technique are presented. This includes C1 ,C2 blending triangular interpolanls and C1 -blending quadrilateral inter polanls for surfaces. The mentioned methods can be generalized to the construction of C" blending interpolants. 相似文献
90.
利用Bridgman-Stockbarger方法在氩气气氛下生长出KZnF3:Eu^3+单晶,测定了晶体的激发光谱、荧光发射光谱和ESR谱,讨论了Eu离子的取代格位。 相似文献