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41.
关于λ-数乘收敛级数的不变性   总被引:5,自引:0,他引:5  
本文证得(1)若λ具有弱滑脊性,那么λ-数乘收敛级数具有对偶不变性。(2)若λ包含C00,那么λ-数乘收敛级数具有全程不变性的充要条件为(λ,β(λ,λβ))是AK-空间。  相似文献   
42.
A multi-plate (MP) mathematical model was proposed by frontal analysis to evaluate nonlinear chromatographic performance. One of its advantages is that the parameters may be easily calculated from experimental data. Moreover, there is a good correlation between it and the equilibrium-dispersive (E-D) or Thomas models. This shows that it can well accommodate both types of band broadening that is comprised of either diffusion-dominated processes or kinetic sorption processes. The MP model can well describe experimental breakthrough curves that were obtained from membrane affinity chromatography and column reversed-phase liquid chromatography. Furthermore, the coefficients of mass transfer may be calculated according to the relationship between the MP model and the E-D or Thomas models.  相似文献   
43.
An automatic adjoint theorem and its applications   总被引:2,自引:0,他引:2  
In this paper, we prove the following automatic adjoint theorem: For any sequence spaces and , if has the signed-weak gliding hump property and is an infinite matrix which transforms into , then the transpose matrix of transforms into , and for any and , . That is, the adjoint operator of automatically exists and is just the transpose matrix of . From the theorem we obtain a class of infinite matrix topological algebras , and prove also a -multiplier convergence theorem of Orlicz-Pettis type. The theorem improves substantially the famous Stiles' Orlicz-Pettis theorem.

  相似文献   

44.
纤维素亲和膜用于内毒素的去除   总被引:5,自引:0,他引:5  
报道了用于内毒素去除的3种新型纤维素亲和膜的制备及应用,并对它们的性能进行了比较。结果表明,这3种亲和膜均能有效去除盐溶液中的内毒素,去除率在90%以上。对人血清白蛋白溶液,季铵盐和壳聚糖亲和膜对内毒素的去除率较高,仍然在90%以上,金属螯合物亲和膜的去除效果不如前两种,去除率仅为83.3%。实验选择不同的亲和膜,考察了它们对内毒素的吸附容量、样品处理量以及再生效果,结果表明吸附量在 2.4×106EU/g以上,样品处理量较大,适合用于小批量医药制剂的生产过程;再生效果较好,可重复使用。  相似文献   
45.
压电化学传感器是一类重要的质量敏感型检测器,由于具有体积小、灵敏度高、响应时间快等优越性而具有极好的应用前景.本文介绍了体声波化学传感器(QCM)和表面声波化学传感器(SAW)的原理,概述了最近几年的应用情况及提高灵敏度的方法,并对其发展趋势进行了展望.  相似文献   
46.
高效液相色谱法直接拆分泮托拉唑钠对映体   总被引:1,自引:0,他引:1  
丁国生  丛润滋  王俊德 《色谱》2004,22(3):241-243
首次使用Kromasil CHI-TBB手性柱在正相条件下直接拆分了泮托拉唑钠对映异构体,考察了流动相组成、酸碱调节剂用量以及流速对对映体分离的影响。优化后的分析条件为:流动相组成为正己烷-异丙醇-乙酸(体积比为95∶5∶0.1)混合溶液,流速2.0 mL/min,柱温25 ℃。所建立的方法具有柱效高、简便快捷及重复性好等优点。  相似文献   
47.
48.
气体温度的红外光谱测量   总被引:1,自引:0,他引:1  
本文综述了利用傅里叶变换红外光谱测量气体温度的原理和方法,并讨论了影响测量温度准确性的各种因素。  相似文献   
49.
A new type of chiral ligand-exchange stationary phase (CLES) was successfully synthesized by treating silica gel with beta-(3,4-epoxycyclohexyl)ethyltrimethoxy silane and opening the epoxy ring by L-isoleucine. The chiral speciation of DL-selenomethionine (DL-SeMet) by high-performance liquid chromatography (HPLC) with UV absorbance on the CLES column was studied. The influences of the contents of copper ion and methanol as well as the pH value in the mobile phase and temperature of the column on the efficiency of resolution of DL-SeMet were investigated in detail. DL-SeMet could be completely resolved within 40 min under the optimal operating conditions of 0.1 mmol/L Cu2+ at 0.05 mol/L KH2PO4 buffer (pH = 5.5) and 35 degrees C temperature of the column. The limits of detection of D- and L-SeMet were 255 ppb and 286 ppb, respectively. This method was applied to determine the D- and L-enantiomers of DL-SeMet in real samples, such as selenized yeast powder and garlic.  相似文献   
50.
A simple preparation process of alkylamide phase for reversed-phase HPLC (RP-HPLC) is described. The process includes aminopropyltrimethoxysilane firstly reacted with octanoyl chloride, then the intermediate was coupled onto porous silica. The resultant bonded silica has a reproducible ligand surface concentration and homogenous bonded ligand distribution on the porous silica. Characterization of prepared packing was carried out with elemental analysis, solid-state 13C NMR and Fourier transform infrared (FT-IR). Chromatographic evaluations were carried out by using a mixture of organic compounds including acidic, basic and neutral analytes under methanol/water as binary mobile phase. The results showed that the stationary phase have excellent chromatographic properties and can be efficiently used for the separation of basic compounds.  相似文献   
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