Journal De Physique Ii最新文献_第8页

Phase Separation in Polymer Solutions Induced by Shear 剪切诱导聚合物溶液中的相分离

Journal De Physique Ii Pub Date : 1997-02-01 DOI: 10.1051/JP2:1997126

A. Onuki, R. Yamamoto, T. Taniguchi

引用次数: 28

Surfactant limited aggregation of hydrophobic molecules in water 表面活性剂限制了疏水分子在水中的聚集

Journal De Physique Ii Pub Date : 1997-02-01 DOI: 10.1051/JP2:1997128

Helene Lannibois, A. Hasmy, R. Botet, O. A. Chariol, B. Cabane

{"title":"Surfactant limited aggregation of hydrophobic molecules in water","authors":"Helene Lannibois, A. Hasmy, R. Botet, O. A. Chariol, B. Cabane","doi":"10.1051/JP2:1997128","DOIUrl":"https://doi.org/10.1051/JP2:1997128","url":null,"abstract":"The precipitation in water of hydrophobic molecules has been studied in presence of added surfactants. Amorphous particles grow through aggregation of clusters of hydrophobic molecules; the growth is terminated by adsorption of surfactant. The particle sizes vary according to the concentrations of hydrophobic molecules and of surfactant molecules. Two regimes have been found for the use of surfactant molecules: at low surfactant concentrations, an efficient regime where all surfactant molecules are adsorbed on the surfaces of the growing particles; at high surfactant concentrations, a wasteful regime, where excess surfactant molecules are left in water. Attempts to reduce the particle sizes by adding increasing amounts of surfactant become inefficient at some point where most of the added surfactant remains in water. These results are explained by a kinetic aggregation model which simulates the competition between aggregation of hydrophobic molecules and adsorption of surfactant. The results of experiments are well reproduced by simulations where aggregation is allowed to proceed unimpeded for a time T, and then adsorption of the surfactant starts. In these conditions, particle sizes are determined by the rate of aggregation and by the value of this time delay.","PeriodicalId":14774,"journal":{"name":"Journal De Physique Ii","volume":"55 1","pages":"319-342"},"PeriodicalIF":0.0,"publicationDate":"1997-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74828455","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: 28

Simplified Mean Field Theory for Polyelectrolyte Phase Behaviour 多电解质相行为的简化平均场理论

Journal De Physique Ii Pub Date : 1997-02-01 DOI: 10.1051/JP2:1997129

P. B. Warren

引用次数: 21

Characterizing the Nature of the Smectic A–Smectic C and Smectic A–Smectic C* Transitions Smectic A-Smectic C和Smectic A-Smectic C*跃迁性质的表征

Journal De Physique Ii Pub Date : 1997-02-01 DOI: 10.1051/JP2:1997120

L. Benguigui, P. Martinoty

引用次数: 5

Diffusion in the Micellar and Hexagonal Phases of the C12EO6/H2O Mixture: A Directional-Growth Study C12EO6/H2O混合物胶束相和六方相的扩散:一个方向生长研究

Journal De Physique Ii Pub Date : 1997-01-01 DOI: 10.1051/JP2:1997117

L. Sallen, P. Oswald, P. Sotta

{"title":"Diffusion in the Micellar and Hexagonal Phases of the C12EO6/H2O Mixture: A Directional-Growth Study","authors":"L. Sallen, P. Oswald, P. Sotta","doi":"10.1051/JP2:1997117","DOIUrl":"https://doi.org/10.1051/JP2:1997117","url":null,"abstract":"Nous avons etudie en croissance directionnelle l'instabilite de Mullins-Sekerka a l'interface entre la phase hexagonale H∞ et la phase micellaire du melange lyotrope C 12 EO 6 +eau. Nous avons d'abord travaille a la concentration azeotrope (50% de surfactant en poids). Lorsque le C 12 EO 6 est pur, le melange se comporte comme un corps pur et l'instabilite de Mullins-Sekerka disparait. Elle reapparait lorsque le savon se degrade par oxydation radicalaire a la lumiere et a la chaleur. Nous avons mesure en fonction de la concentration en impuretes et de l'orientation des colonnes moleculaires, la vitesse critique, la longueur d'onde et la vitesse de derive des cellules en croissance et en fusion. De ces donnees experimentales, nous avons deduit les trois coefficients de diffusion moyens des impuretes dans la phase micellaire (D L i ) et dans la phase hexagonale, parallelement (D∥ i ) et perpendiculairement (D⊥ i ) aux colonnes moleculaires. Nous nous sommes ensuite ecartes legerement de la concentration azeotrope en prenant soin d'eviter la degradation du surfactant. Des experiences analogues en croissance et en fusion nous ont permis de determiner les trois coefficients de diffusion D L , D∥ et D⊥ du champ de concentration en surfactant. Les valeurs trouvees different de celles obtenues pour les impuretes et sont comparees aux coefficients de diffusion individuels de l'eau et du C 12 EO 6 mesures par RMN. Enfin, nous avons mesure le coefficient cinetique d'attachement moleculaire a l'interface. Nous avons trouve que la cinetique est lineaire et symetrique en croissance et en fusion.","PeriodicalId":14774,"journal":{"name":"Journal De Physique Ii","volume":"12 1","pages":"107-138"},"PeriodicalIF":0.0,"publicationDate":"1997-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79614991","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: 8

Lattice of passages connecting membranes 连接膜的通道晶格

Journal De Physique Ii Pub Date : 1997-01-01 DOI: 10.1051/JP2:1997112

T. Charitat, B. Fourcade

引用次数: 17

Dynamics in blends of long polymers with unentangled short chains 无纠缠短链长聚合物共混物动力学

Journal De Physique Ii Pub Date : 1997-01-01 DOI: 10.1051/JP2:1997116

R. Colby

引用次数: 3

Thermodynamic Theory of Counterion Association in Rigid Polyelectrolytes 刚性聚电解质中反离子缔合的热力学理论

Journal De Physique Ii Pub Date : 1997-01-01 DOI: 10.1051/JP2:1997113

Y. Levin, M. Barbosa

{"title":"Thermodynamic Theory of Counterion Association in Rigid Polyelectrolytes","authors":"Y. Levin, M. Barbosa","doi":"10.1051/JP2:1997113","DOIUrl":"https://doi.org/10.1051/JP2:1997113","url":null,"abstract":"We present a new theory of rodlike polyelectrolyte solutions. It is found that at low densities, and below teInperature T~i, the counterions associate with the polyions forIn- ing clusters consisting of one polyion and n counterions. The distribution of du8ters sizes is Gaussian, leading to strong logarithmic corrections to the liIniting laws obtained by Manning. In the Inathelnatical limit of infinite dilution the distribution of the cluster sizes approaches a delta function centered on the value postulated by Manning. Above Tci the solution consists of free (unassociated) counterions and polyions, and the liIniting laws reInain unaffected. Finally, unlike soIne recent suggestions, we denlonstrate that the counterion condensation is distinct fron1the Kosterlitz-Thouless transition. In fact, the association phenoInena inside a polyelec- trolyte solution can be coInpared to a fornlation of nlicelles in anlphiphilic systenls. There is, however, an iInportant difference. While the aInphiphilic rnicelles can be diluted away (bro- ken apart) by increasing the aInount of 801vent, the strong electrostatic interactions keep the polyion-counterion8 clusters froIn dissociating, even a8 the concentration of polyelectrolyte is decrea8ed all the way down to zero.","PeriodicalId":14774,"journal":{"name":"Journal De Physique Ii","volume":"336 1","pages":"37-55"},"PeriodicalIF":0.0,"publicationDate":"1997-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73882447","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: 10

IR-Modulation Spectroscopy on the Collective Dynamics of Free-Standing Ferroelectric Liquid Crystalline Films 独立铁电液晶膜集体动力学的红外调制光谱研究

Journal De Physique Ii Pub Date : 1997-01-01 DOI: 10.1051/JP2:1997114

N. Klöpper, F. Kremer, T. Fischer

引用次数: 1

Adsorption Study on DDAB Bilayers Using Contrast Variation with SANS 用对比变化法研究双分子膜对DDAB的吸附

Journal De Physique Ii Pub Date : 1997-01-01 DOI: 10.1051/JP2:1997110

F. Ricoul, M. Dubois, T. Zemb

引用次数: 6