Colloids and Surfaces最新文献_第5页

The viscoelastic properties of polystyrene particles bearing poly(ethylene oxide)-poly(propylene oxide) ABA block copolymers 聚苯乙烯颗粒承载聚环氧乙烷-聚环氧丙烷ABA嵌段共聚物的粘弹性性能

Colloids and Surfaces Pub Date : 1992-11-17 DOI: 10.1016/0166-6622(92)80210-S

I.T. Kim, P.F. Luckham

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引用次数: 18

Thermodynamic parameters characterizing complexes of alkali metal cations with dibenzo-24-crown-8 in the water—nitrobenzene extraction system 水-硝基苯萃取体系中碱金属阳离子与24-冠-8配合物的热力学参数表征

Colloids and Surfaces Pub Date : 1992-11-17 DOI: 10.1016/0166-6622(92)80215-N

Emanuel Makrlík

引用次数: 0

Superfast electrophoresis of ion-exchanger particles 离子交换剂颗粒的超高速电泳

Colloids and Surfaces Pub Date : 1992-11-11 DOI: 10.1016/0166-6622(92)80198-B

Alexander A. Baran, Yana A. Babich, Andrey A. Tarovsky, Natalia A. Mischuk

{"title":"Superfast electrophoresis of ion-exchanger particles","authors":"Alexander A. Baran, Yana A. Babich, Andrey A. Tarovsky, Natalia A. Mischuk","doi":"10.1016/0166-6622(92)80198-B","DOIUrl":"10.1016/0166-6622(92)80198-B","url":null,"abstract":"<div>It has been shown that the electrophoretic mobility of large ion-exchanger particles (diameter, 250–1000 μm) or fibres (length, 100–1000 μm) in strong electric fields (100–1000 V cm−1) exceeds the electrophoretic mobility values typical for non-conducting particles by one or two orders of magnitude. This phenomenon was called “electrophoresis of the second kind” or “superfast electrophoresis”. The mobility of such particles depends on the conductivity ratio between the particles and medium and increases linearly with the electric field gradient and the particle size. This is in contrast to classical electrophoresis which does not depend on these parameters.The effect of electrolytes and pH on the electrophoretic mobility in strong fields is due to the change in the conductivity ratio mentioned above. Changes in the electric double layer parameters do not affect the mobility.Electrophoresis of the second kind is due to the interaction of a strong electric field with the space charge near the surface of unipolar conducting particles. It occurs only when the conductivity of particles exceeds the conductivity of the medium. New methods to observe this phenomenon were developed.</div>","PeriodicalId":10488,"journal":{"name":"Colloids and Surfaces","volume":"68 3","pages":"Pages 141-151"},"PeriodicalIF":0.0,"publicationDate":"1992-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0166-6622(92)80198-B","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74981361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 22

The conductivity and the adsorption capacity of surfactant modified hydrous titanium oxide gels 表面活性剂改性含水氧化钛凝胶的导电性能和吸附性能

Colloids and Surfaces Pub Date : 1992-11-11 DOI: 10.1016/0166-6622(92)80202-D

Huizhen Chen , E. Ruckenstein

引用次数: 1

Adsorption—desorption of serum albumin on bare mica surfaces 血清白蛋白在裸云母表面的吸附-解吸

Colloids and Surfaces Pub Date : 1992-11-11 DOI: 10.1016/0166-6622(92)80203-E

Jean-Paul Gallinet, Bernard Gauthier-Manuel

引用次数: 19

Droplet size and dynamics in water-in-oil microemulsions 油包水微乳中的液滴大小和动力学

Colloids and Surfaces Pub Date : 1992-11-11 DOI: 10.1016/0166-6622(92)80205-G

J. Lang, N. Lalem, R. Zana

{"title":"Droplet size and dynamics in water-in-oil microemulsions","authors":"J. Lang, N. Lalem, R. Zana","doi":"10.1016/0166-6622(92)80205-G","DOIUrl":"10.1016/0166-6622(92)80205-G","url":null,"abstract":"<div>This paper is a short review of a systematic study of the effect of oil, surfactant and cosurfactant alkyl chain length (with n, m and nc carbon atoms in the alkyl chain, respectively) and temperature (T) on the droplet size, rate constant kc for exchange of material between colliding droplets, and attractive interactions between droplets in water-in-oil microemulsions. In agreement will current theories on the stability of water-in-oil microemulsions, the droplet size, kc and attractive interactions between droplets increase as n and T increase or as m and nc decrease. Correlations have been found between droplet size, value of kc, magnitude of interdroplet attractive interactions, appearance of electrical conductivity percolation and water solubility as one of the parameters n, m, nc or T is changed. It has been shown, for instance, that electrical conductivity percolation appears only for systems characterized by a value of kc larger than (1–2)·109 M−1 s−1. It has also been shown that electrical measurements as a function of the molar concentration ratio ω (equal to [water]/[surfactant]) can give qualitative information concerning the variation of droplet size, kc and attractive interdroplet interactions with n, m and nc.</div>","PeriodicalId":10488,"journal":{"name":"Colloids and Surfaces","volume":"68 3","pages":"Pages 199-206"},"PeriodicalIF":0.0,"publicationDate":"1992-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0166-6622(92)80205-G","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82727260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 18

The surface charge of kaolin 高岭土的表面电荷

Colloids and Surfaces Pub Date : 1992-11-11 DOI: 10.1016/0166-6622(92)80200-L

T.M. Herrington, A.Q. Clarke, J.C. Watts

引用次数: 74

Penetration of chlorcyclizine and ampicillin into mixed phospholipid—oleic acid monolayers 氯环嗪和氨苄西林在混合磷脂-油酸单分子膜中的渗透

Colloids and Surfaces Pub Date : 1992-11-11 DOI: 10.1016/0166-6622(92)80206-H

M. Casas , M.M. Boissonnade , A. Baszkin

{"title":"Penetration of chlorcyclizine and ampicillin into mixed phospholipid—oleic acid monolayers","authors":"M. Casas , M.M. Boissonnade , A. Baszkin","doi":"10.1016/0166-6622(92)80206-H","DOIUrl":"10.1016/0166-6622(92)80206-H","url":null,"abstract":"<div>Surface tension-solution concentration relationships reveal that in spite of the higher efficiency of adsorption displayed by chlorcyclizine relative to ampicillin, the effectiveness of adsorption was superior for the latter. There differences in adsorption behaviour between the two drugs studied have been attributed to the differences in their chemical structure. Chlorcyclizine with its two branched hydrophobic benzyl groups exhibits a higher thermodynamic driving force for adsorption than does ampicillin with its one benzyl group.The penetration of these drugs into phospholipid, oleic acid and their mixed monolayers has been assessed by surface pressure and surface potential measurements. Although more space is required to accommodate penetrating chlorcyclizine molecules in a spread monolayer, their penetration into an oleic acid monolayer is higher than that of ampicillin. and is most probably due to an ionic interaction between the drug cation and the oleic acid carboxylate group. The penetration into phospholipid monolayers (which are highly incompressible) and their mixed monolayers with oleic acid was superior for ampicillin at high solution concentrations. The surface potential data corroborate the surface pressure data, but indicate that the presence oleic acid molecules in the monolayers exerts an unfavourable dipolar matching on adsorbing drug molecules, the effect being superior in the case of ampicillin.</div>","PeriodicalId":10488,"journal":{"name":"Colloids and Surfaces","volume":"68 3","pages":"Pages 207-214"},"PeriodicalIF":0.0,"publicationDate":"1992-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0166-6622(92)80206-H","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91529353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Stability constants of tris(2,2′-bipyridine) complexes of Fe2+, Co2+, Ni2+, Cu2+ and Zn2+ in 1,2-dichloroethane saturated with water Fe2+、Co2+、Ni2+、Cu2+和Zn2+三(2,2′-联吡啶)配合物在水饱和1,2-二氯乙烷中的稳定性常数

Colloids and Surfaces Pub Date : 1992-11-11 DOI: 10.1016/0166-6622(92)80204-F

Emanuel Makrlík , Petr Van̆ura

引用次数: 8

Mixed adsorption of sodium dodecylsulfate and ethoxylated nonylphenol on TiO2 and the stability of TiO2 dispersions in sodium dodecylsulfate—ethoxylated nonylphenol mixed solutions 十二烷基硫酸钠和乙氧基壬基苯酚在TiO2上的混合吸附及TiO2在十二烷基硫酸钠-乙氧基壬基苯酚混合溶液中的分散性

Colloids and Surfaces Pub Date : 1992-11-11 DOI: 10.1016/0166-6622(92)80201-C

Chiming Ma, Yin Xia

{"title":"Mixed adsorption of sodium dodecylsulfate and ethoxylated nonylphenol on TiO2 and the stability of TiO2 dispersions in sodium dodecylsulfate—ethoxylated nonylphenol mixed solutions","authors":"Chiming Ma, Yin Xia","doi":"10.1016/0166-6622(92)80201-C","DOIUrl":"10.1016/0166-6622(92)80201-C","url":null,"abstract":"<div>The adsorption of sodium dodecylsulfate (SDS) and ethoxylated nonylphenol (NP-12) from their mixed solutions on TiO2 and the stability of TiO2 dispersions in SDS—NP-12 mixed solutions have been investigated. The NP-12 alone is almost not adsorbed on the TiO2 surface. However, the amount of NP-12 adsorbed on TiO2 increases by more than 50 times in the presence of a certain amount of SDS in solution, and decreases again at higher concentrations of SDS. The adsorption of SDS on the surface of TiO2 from the SDS—NP-12 mixed solutions displays similar characteristics to a lesser degree. The stability of TiO2 dispersions in the mixed solutions of SDS and NP-12 is shown to be consistent with the adsorption results. The synergistic and antagonistic effects of SDS and NP-12 on their adsorption on TiO2 and on the stabilization of the TiO2 dispersions were interpreted in terms of the formation of mixed hemimicelles on the TiO2 surface and mixed micelles in solution.</div>","PeriodicalId":10488,"journal":{"name":"Colloids and Surfaces","volume":"68 3","pages":"Pages 171-177"},"PeriodicalIF":0.0,"publicationDate":"1992-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0166-6622(92)80201-C","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89934248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 13