Colloids and Surfaces最新文献_第4页

The effect of surface heterogeneity on pseudo-line tension and the flotation limit of fine particles 表面不均匀性对伪线张力及细粒浮选极限的影响

Colloids and Surfaces Pub Date : 1992-11-23 DOI: 10.1016/0166-6622(92)80236-U

Jaroslaw Drelich, Jan D. Miller

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引用次数: 52

Equilibrium properties of reversibly flocculated dispersions 可逆絮凝分散体的平衡特性

Colloids and Surfaces Pub Date : 1992-11-23 DOI: 10.1016/0166-6622(92)80233-R

E. van der Aerschot , J. Mewis

引用次数: 29

Surface chemistry of silicon nitride powders: Adsorption from non-aqueous solutions 氮化硅粉末的表面化学:非水溶液的吸附

Colloids and Surfaces Pub Date : 1992-11-23 DOI: 10.1016/0166-6622(92)80238-W

Lennart Bergström

引用次数: 16

Predispersed solvent extraction of dilute products using colloidal gas aphrons and colloidal liquid aphrons: Aphron preparation, stability and size 用胶体气阿佛龙和胶体液阿佛龙预分散溶剂萃取稀产物:阿佛龙的制备、稳定性和尺寸

Colloids and Surfaces Pub Date : 1992-11-23 DOI: 10.1016/0166-6622(92)80239-X

K. Matsushita , A.H. Mollah, D.C. Stuckey, C. del Cerro, A.I. Bailey

{"title":"Predispersed solvent extraction of dilute products using colloidal gas aphrons and colloidal liquid aphrons: Aphron preparation, stability and size","authors":"K. Matsushita , A.H. Mollah, D.C. Stuckey, C. del Cerro, A.I. Bailey","doi":"10.1016/0166-6622(92)80239-X","DOIUrl":"10.1016/0166-6622(92)80239-X","url":null,"abstract":"<div>Early work on colloidal gas aphrons (CGAs) and Colloidal liquid aphrons (CLAs) has shown that they have considerable potential in the field of predispersed solvent extraction (PDSE). While their area of application is potentially very broad, their most promising use is in downstream separation in biotechnology where products are very dilute and occur in complex mixtures. Since little work has been done in this area, this preliminary study examined the influence of a range or solvents, varying from non-polar to mildly polar, and a variety of ionic and non-ionic surfactants, on CLA size, stability and phase volume ratio (PVR, volume ratio of the dispersed oil phase to the continuous aqueous phase). In addition, the effect of surfactant type, stirring speed and time, on the formation of CGAs was also studied. The results show that CLAs can be formulated with quite polar solvents (e.g. pentanol), and their stability increases as the HLB (hydrophilic/lipophilic balance) number of the non-ionic surfactant increases. CLAs could be formulated with PVRs as high as 20 without coalescence, which is markedly higher than with microemulsions, and seems to indicate that the liquid aphrons are stabilised by more than a surfactant monolayer. Finally, it was found that CGAs could be formulated as a foam with a half-life of 6 min, and that they could be used to separate dispersed CLAs effectively from a bulk solution.</div>","PeriodicalId":10488,"journal":{"name":"Colloids and Surfaces","volume":"69 1","pages":"Pages 65-72"},"PeriodicalIF":0.0,"publicationDate":"1992-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0166-6622(92)80239-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91540951","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: 75

Characterization of foam stability by the use of foam models 2. Results and discussion 用泡沫模型表征泡沫的稳定性结果与讨论

Colloids and Surfaces Pub Date : 1992-11-17 DOI: 10.1016/0166-6622(92)80213-L

T. Szekrényesy, K. Liktor, N. Sándor

引用次数: 10

Dynamic surface properties of adsorbed protein solutions: BSA, casein and buttermilk 吸附蛋白溶液的动态表面特性:牛血清白蛋白，酪蛋白和酪乳

Colloids and Surfaces Pub Date : 1992-11-17 DOI: 10.1016/0166-6622(92)80208-J

Guido Serrien, Gerda Geeraerts, Loknath Ghosh, Paul Joos

引用次数: 91

Characterization of foam stability by the use of foam models 1. Models and derived lifetimes 用泡沫模型表征泡沫的稳定性模型和衍生的寿命

Colloids and Surfaces Pub Date : 1992-11-17 DOI: 10.1016/0166-6622(92)80212-K

T. Szekrényesy, K. Liktor, N. Sándor