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41.
通过大块液膜体系研究了四烷基锡的碳链长度、载体浓度.NO_2~-浓度及抗衡离子等因素对NO_2~_穿透含四烷基锡的液膜的传质速率的影响,讨论了它们与四烷基锡为载体的离子电极性能间的关系。NO_2~-通过四烷基锡为载体的液膜的迁移规律符合离子对传输模式。 相似文献
42.
以国产微晶纤维素膜作固体基质五种多环芳烃的室温磷光法研究 总被引:2,自引:1,他引:2
本文考察了10种国产纤维素膜用于多环芳烃固体基质室温磷光(SS-RTP)的可行性。实验表明:MN-C和MN-P两种型号的微晶纤维素膜用于多环芳烃的SS-RTP是适宜的。阴离子交换纤维素膜、CM-纤维素膜和聚酰胺-6膜也能诱导出多环芳烃的RTP来,但其性能逊于前两种。故本文应用MN-C和MN-P两种微晶纤维素膜基质考察了五种多环芳烃的RTP特征,并建立了它们的SS-RTP新方法。并与用滤纸作基质的实验结果进行了比较,表明两种新的固体基质的RTP性能优于滤纸基质。 相似文献
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The inhibitory effect of a series of neutral lipophilic solutes (methanol, ethanol, n-propanol, iso-propanol, n-butanol, iso-amylalcohol, n-hexanol, diethylether, nitrobenzene, and pyridine) on the diffusional water permeability (Pd, tot) of bovine erythrocyte membrane at 25 degrees C was studied in comparison to that of p-chloromercuri benzoate (pCMB). Permeability data were obtained by measuring the transmembrane diffusional water exchange time tau(exch) using an 1H-T2 NMR technique. Maximal inhibition by approximately 50% of Pd, tot was produced by 2 mM pCMB which completely blocked the membrane water channels in 20 min, hence suggesting the channel-to-lipid diffusional water permeability ratio of about 1:1. Furthermore, the maximal inhibitory effect of pCMB in combination with the lipophilic solutes was lower than that of pCMB alone. As pCMB does not interfere with the lipid bilayer, and provided that it blocks the water channels in solute presence as well, this confirms that the solutes induce an increase in the lipid-mediated background water permeability contribution (Pd, lipid) by the formation of aqueous leaks in the membrane hydrophobic barrier. However, faster but less efficient in permeability inhibition than pCMB (either alone or combined with solutes) were the lipophilic solutes alone. Taken together, the results indicate that the lipophilic solutes suppress the membrane total permeability Pd, tot by two opposing effects: a reduction of its channel-mediated part (Pd, channel) to the extent exceeding that of a simultaneous Pd, lipid increase. The inhibitory potency of the solutes tested appears to be correlated with their solubility in the membrane medium. 相似文献
45.
有机金属络合物用于高分子富氧膜的研究进展 总被引:2,自引:0,他引:2
本文介绍了能够可逆吸附分子氧的有机金属络合物用于高分子富氧膜的研究进展,以及以双重吸附理论进行的膜的促进输送机理。 相似文献
46.
Paolo Zatta Tamas KissMario Suwalsky Guy Berthon 《Coordination chemistry reviews》2002,228(2):271-284
Aluminium has been known as a neurotoxic agent to experimental animals since the last century (Arch. Exp. Pharmacol. 40 (1897) 98). However, great interest arose in it bioinorganic chemistry as well biology when it was demonstrated to be the causative agent in pathologies related to the long-term dialysis treatment of uremic subjects with renal failure (Life Chem. 11 (1994) 197), and as a potential etiopathogenic cofactor for several neurodegenerative diseases. The inorganic biochemistry of aluminium is still largely to be discovered. In this review the pro-oxidative property of aluminium toward biological membrane will be presented and its implications in involvement in human pathology will be discussed in an interdisciplinary frame from the bioinorganic point of view. 相似文献
47.
CdSe纳米线阵列的制备及其表征(英) 总被引:1,自引:0,他引:1
通过在含有SeSO32-和Cd2+的室温水溶液中,用模板-电沉积法在纳米孔阵列阳极氧化铝膜(AAM)模板中制备了高有序性的CdSe纳米线阵列,并对其形貌、结构和组分进行了表征。扫描电子显微镜(SEM)和透射电子显微镜(TEM)结果表明,纳米线阵列中的CdSe纳米线具有相同的长度和直径,分别对应于使用的AAM模板的厚度和孔径;X-射线衍射(XRD)和X-射线能谱(EDAX)结果表明,CdSe纳米线中Cd和Se的化学组成非常接近于1∶1,其结构为立方CdSe。另外,对模板-电沉积法制备CdSe纳米线的机理进行了讨论。 相似文献
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The thickness and the porosity of a deposit during ultrafiltration experiments are determined using an electrochemical method. Twenty microelectrodes are mounted flush to a ceramic plane membrane and maps of deposit thickness are determined for three inlet/outlet distributors configurations. Combining an electrochemical method and a step transient method, the determination of the thickness and the porosity of a particles deposit is performed. These local thickness and porosity values are analyzed thanks to wall shear stress local measurements obtained in a previous work [Sep. Sci. Technol. 37 (10) (2002) 2251]. The results emphasize the heterogeneity of the deposit thickness, especially in zones of low wall shear stress. Furthermore, the porosity values of the deposit are ranged between 0.3 and 0.8 as a function of the location at the membrane surface. 相似文献
50.