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941.
The inverse method of isotherm determination consists in calculating the numerical values of the coefficients of an isotherm model that give a set of chromatographic profiles in best possible agreement with the set of experimental profiles available. This method was applied to determine the adsorption isotherms of the 1-indanol enantiomers on a cellulose tribenzoate chiral stationary phase. Both single-component and competitive isotherms were determined by using no more than one or two overloaded band profiles. The isotherms determined from the overloaded band profiles agreed extremely well with the isotherms determined by frontal analysis. Several isotherm models were used and tested. The best-fit isotherm was selected by means of statistical evaluation of the results. The results show that the adsorption is best characterized with a model describing heterogeneous adsorption with bimodal adsorption energy distribution.  相似文献   
942.
用带误差项的Ishikawa迭代过程逼近φ-强增生算子的零点   总被引:18,自引:0,他引:18  
本文使用新的分析技巧研究了一致光滑Banach空间中φ 强增生算子的零点逼近问题,所得结果改进和扩展了近期许多相应的结果  相似文献   
943.
高能工业CT用新型X射线源焦斑测量   总被引:3,自引:3,他引:3       下载免费PDF全文
 为了获得较高的空间分辩率,设计了一种新型小束斑驻波电子直线加速器,该加速器取消了加速腔中的鼻锥结构,而在耦合腔中设置鼻锥结构。用狭缝法代替小孔法测得X射线源的焦斑尺寸为1.4mm。讨论了射线源焦点对成像质量的影响,分析了在高能条件下小孔法不适合用于焦点测量的物理原因,用4种测量方法测量了该高能X射线源的参数,测得该系统的成像极限分辩率为2.5 lp/mm,最后对实验结果进行了分析。  相似文献   
944.
Total absorption is realized theoretically in a graphene-outside-cavity resonator. The structure is composed of the FP-Fano hybrid resonance cavity. Changing the thickness of grating exciting Fano resonance, the absorption-mode number can be tuned effectively. For the focused double-mode absorption, the resonances behave insensitively with the variation of chemical potential of graphene. Varying the geometry of grating can control the coupling extent of two modes. Also, by manipulating the period number of two-side multilayers around graphene, the absorption, shift and number of modes are governed.  相似文献   
945.
It is of engineering importance to accurately predict the surface cooling characteristics in bath quenching of metals and alloys. In this investigation, the surface cooling characteristics in quenching of Wolfson probe are estimated with reasonable accuracy by solving an inverse heat conduction problem. Regularization method is used for smoothening the input temperature measurements at probe center, for superior inversion estimates. The reverse pool-boiling curve is captured on bath quenching characteristic, plotted as cooling velocity versus surface temperature. The prime advantage is the bypassing of convection coefficients, which are uncertain in pool boiling.  相似文献   
946.
947.
Citrinin (CIT) is a nephrotoxic mycotoxin initially isolated from filamentous fungus Penicilliu citrinum. It was later isolated from several other species, such as Aspergillus and Monascus. It has a conjugated, planar structure that gives it a natural fluorescence ability, which can be used to develop sensitive methods for detecting CIT in food. In this paper, we used the spectro?uorescence technique to study the effects of pH value, β-cyclodextrin (β-CD) and organic solvents on the CIT fluorescence intensity. The results show that lower pH value, aceitc acid, β-CD and acetonitrile can induce a higher fluorescence intensity of CIT, but methanol or H2O has a decreasing effect on the fluorescence intensity of CIT. Findings in this study provide a theoretical basis for development of a high sensitivity fluorescence-based trace analysis for CIT detection.  相似文献   
948.
鲁路  周长忍 《高分子科学》2016,34(2):185-194
Herein, we present a novel way for the production of self-healing hydrogels with stretch beyond 4200% than their initial length and relatively high tensile strength(0.1?0.25 MPa). Furthermore, the hydrogel was insensitive to notch. Even for the samples containing V-notches, a stretch of 2300% was demonstrated. The hydrogels were developed by in situ crosslinking of the self-assembled colloidal poly(acrylic acid)(PAA)/functionalized polyhedral oligomeric silsesquioxane(POSS) micelles. This was achieved by the addition of functionalized polyhedral oligomeric silsesquioxane with tertiary amines and hydroxyls(POSS-AH) into the PAA reaction solution. The POSS-AH led to micellar growth, then the dualcrosslinked network was constructed. One type of crosslink was formed by hydrogen-bonding and ionic interactions between PAA chains and POSS-AH, the other type of crosslink was formed by covalent bonds between PAA and bis(N,N'-methylenebis-acrylamide).  相似文献   
949.
Journal of Radioanalytical and Nuclear Chemistry - The carboxyl-modified multiwalled carbon nanotubes were immobilized in chitosan-based composite membranes (CS-CNTs) which were used as efficient...  相似文献   
950.
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