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111.
报道了以茈为荧光探针,探讨小剂量~(60)Co γ射线照射后小鼠胸腺细胞膜流动性的变化。结果表明,剂量在0.25-1.00Gy范围,胸腺细胞膜流动性降低与剂量之间呈明显线性关系。从0.50Gy起,辐照组荧光强度比值I_1/I_2与I_3/I_2与对照组的比较存有显著差异(P<0.05)。提示淋巴细胞膜流动性的变化可作为小剂量辐照早期效应的敏感指标。  相似文献   
112.
二硫代磷酸硫化氧钼与硫,磷添加剂的复配特性研究   总被引:1,自引:0,他引:1  
研究了二烷基二硫代磷酸硫化氧钼(MoDTP)摩擦改进剂及其与硫、磷、硫-磷型添加剂复合的抗磨减摩性能。试验表明,经过适当复配后,这类合活性元素的添加剂对MoDTP的抗磨减摩性能均有增效作用,同一类型添加剂的活性愈高,增效作用愈显著。同时利用扫描电镜和X-射线能谱仪进行摩擦副表面膜的形貌照相及元素分析,对复合作用的机理进行了初步探讨。  相似文献   
113.
A new calculation procedure for free‐volume parameters is considered in this work by using viscosity prediction methods and the Levenberg‐Marquardt calculation scheme. All parameters used in the Vrentas–Duda free‐volume theory can be estimated from pure component properties. The prediction results are compared with experimental data for some polymer/solvent systems. The diffusion coefficient calculated by Vrentas–Duda theory can be used in the modeling of membrane separation processes. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
114.
A different newly designed cationic exchange polymer membrane and anionic exchange polymer membrane were introduced, and also the transport properties of these polymeric membranes were investigated in this study. The transport properties of these polymer membranes in contact with ferrocene redox derivatives were estimated by using electrochemical techniques such as cyclicvoltammetry, chronopotentiometry, and chronoamperometry techniques, respectively. The used ferrocene redox substances, which have different functional groups, were (Ferrocenylmethyl) trimethylamonium iodide, FcMA, Ferrocenedimethanol, FcDM, and Ferrocene carboxylic acid, FcCA. It indicated that the performance of a membrane depended on the content of polymer gel, anionic exchange polymer site (20 wt % and 50 wt %) or cationic polymer exchange site (20 wt % and 50 wt %), and the efficiency of the functional groups of cationic and anionic exchange polymer site as well. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
115.
Using nickel-2,2′-dipyridyl complex as a template, N-vinyl-2-pyrrolidone as the metal coordination functional monomer, and ethylene glycol dimethacrylate as the crosslinker, polyvinylidene fluoride (PVDF) hollow fiber ultrafiltration membrane as the supported membrane, metal complex imprinted polymeric membranes were prepared. The association constant of template-monomer interaction in the prepolymerization solution was estimated to be 4.38 × 104 (L/mol)2 by spectrophotometric titration analysis. The attenuated total reflection Fourier transform infrared spectroscopy and scanning electron micrograph characterization indicated that the surface of the support PVDF membrane was completely coated by the imprinted polymer layer after modification. The imprinted membranes exhibited the selective permeability for the template in certain nickel acetate solution. The molecularly imprinted membranes gave higher permeation separation factors at about pH 6, whereas increasing pressure would lower the separation ability. The effects of ion concentration, cations and counterions, ligand selectivity, pH, and trans-membrane pressure were investigated and the permeation performances of the imprinted membranes could be regarded as facilitated transport mechanism. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
116.
The charged mosaic polymer membrane (CMM) without reinforcement and the composite charged mosaic polymer membrane (CCMM) with reinforcement were investigated in terms of salt and water transport (permeability). The composite charged mosaic polymer membrane (CCMM) with reinforcement showed a unique transport behavior such as preferential material transport Lp and ω. Water permeability coefficient, Lp and salt permeability coefficient, ω were estimated by taking account of active layer thickness of composite polymer gel. The Lp and ω values of CCMM with reinforcement were larger than those of CMM without reinforcement. On the other hand, the reflection coefficient of CCMM, σ, showed negative value, which suggested preferential material transport to solvent transport. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
117.
The authors report 3 picture-word interference experiments in which they explore some properties of the agreement process in speech production. In Experiment 1, Croatian speakers were asked to produce utterances in which the noun's gender value had an impact on the selection of gender-marked freestanding morphemes (pronouns) while ignoring the presentation of same- or different-gender distractor words. In Experiments 2 and 3, Croatian speakers were asked to name the same pictures using noun phrases in which the noun's gender value surfaced as an inflectional suffix. Different-gender distractors interfered more than same-gender distractors (the gender congruency effect) in Experiment 1, but not in Experiments 2 and 3. These contrasting results show that the cause of the gender congruency effect is not at the level where lexical-grammatical information is selected but at the level of selection of freestanding morphemes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
118.
膜分离技术在制药工业中的应用   总被引:9,自引:0,他引:9  
膜分离技术在制药工业中的应用包括生物发酵制药、中药生产和现代生物技术等.膜分离技术在抗生素、半合成抗生素、维生素和氨基酸生产中尤其常见.随着膜材料、膜组件和膜设备的不断改进,膜分离技术在制药工业中将扮演越来越重要角色.  相似文献   
119.
介绍了升降膜法双效逆流蒸发生产50%离子膜法烧碱的工艺流程、主要设备、装置特点及运行情况.  相似文献   
120.
超滤膜的改性研究及应用   总被引:14,自引:0,他引:14  
陆晓峰  卞晓锴 《膜科学与技术》2003,23(4):97-102,115
随着超滤膜技术的发展,人们对超滤膜提出了各种各样的特性要求,其中解决膜表面的污染问题变得越来越紧迫.超滤膜改性,尤其是在膜表面引入亲水性基团是解决问题的关键.本文从这点出发,结合自身的工作,总结了近年高分子超滤膜改性方面的研究进展,包括表面活性剂在膜表面的吸附改性、等离子体改性、辐照改性、高分子合金和表面化学反应等几种改性方法.  相似文献   
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