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91.
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Ionomeric composites based on sepiolite and hydrogenated poly(styrene butadiene) block copolymer were obtained and characterized from a microstructural and electrical point of view. Before blending, because of the high silanol group concentration in the sepiolite, the latter could be organophilized with suitable coupling agents. The resulting materials were easily processed into thin films or membranes 0.2–0.4 mm thick, their conductivity in some cases approaching 10?1 S/cm. Their suitability for film formation and good electrical properties indicate potential applications as electrolytes in polymer fuel cells. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 3512–3519, 2002 相似文献
94.
P Casolo D Mosca C Amorotti B Drei A Raspadori P Di Blasio E Ganz G De Luca G Colli R De Maria D Amuso 《Canadian Metallurgical Quarterly》1997,68(2):207-11; discussion 212
Primary and sole breast lymphoma is a very rare disease. With the review of our series of 616 cases operated on for breast cancer, only 3 cases (0.48%) of primary breast non-Hodgkin lymphoma (LNH) have been observed. The authors outline the problems concerning diagnosis and therapy of this rare disease: pathological and immunohistochemical aspects are discussed. They stress the importance of staging in order to plan a correct multidisciplinary approach. 相似文献
95.
96.
Juntunen Cindy L.; Atkinson Donald R.; Reyes Carla; Gutierrez Maria 《Canadian Metallurgical Quarterly》1994,31(2):327
Investigated whether (1) feminist identity development for women therapists was related to their use of feminist therapy behaviors (FTBs) and (2) feminist identity development and use of FTBs for women therapists were related to self-identification as a feminist therapist. 153 women psychologists (aged 30–77 yrs) were administered a women's issues in therapy questionnaire, which included a short version of the Feminist Identity Scale (FIS; K. M. Rickard, 1989, 1990). Ss were categorized into stages of feminine identity development according to their scores on 4 subscales of the FIS: Passive-Acceptance (PA), Revelation (REV), Embeddedness (EMB), and Synthesis (SYN). Ss scoring high on SYN and REV, and low on PA, reported greater use of FTBs; scores on the EMB were not related to the use of FTBs. All 4 subscales were predictive of women therapists who self-identified as feminist therapists. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
97.
Sandra Aparecida de Assis Pedro Fernandes Bruno Sommer Ferreira Joaquim MS Cabral Olga Maria Mascarenhas Faria Oliveira 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2004,79(3):277-280
A partially purified extract of pectinmethylesterase (PME) from acerola fruit was immobilized on various supports: glass, celite, chrysotile, agarose, concanavalin A Sepharose 4B, egg shell, polyacrylamide and gelatin. In addition, reticulation with glutaraldehyde was assessed, as well as the use of gelatin in the presence of celite, glass and silica. The highest immobilization yields were obtained when the pectinmethylesterase was immobilized in concanavalin A Sepharose 4B (81.7%) and in gelatin‐water (78.0%). Copyright © 2004 Society of Chemical Industry 相似文献
98.
Molecular model systems based on propyl phosphonic acid (ppa) were studied by means of density functional theory calculations in order to describe the acid-acid interaction and the formation of the hydration sphere. The formation of ppa dimers is reported and the energetic difference between two dimer structures is presented. The hydration sphere of ppa was represented by model systems ppa(H2O)n, for which the system with n=4 formed the first hydration sphere (h1), while n=7 can be considered a good approximation to the complete inner hydration sphere around the phosphonic acid group. The study of the ppa-H+ (H2O)n model systems showed an interesting structural behavior comparatively to the ppa(H2O)n systems. The protonated acids exhibited equivalent phosphorous-oxygen bonds and a general molecular structure is proposed to represent these protonated species. 相似文献
99.
Daniela D'Amato Maria Rosaria Corbo Matteo Alessandro Del Nobile & Milena Sinigaglia 《International Journal of Food Science & Technology》2006,41(10):1152-1157
In enology, alcoholic fermentation is a complex process involving several mechanisms. Slow and incomplete alcoholic fermentation is a chronic problem for the wine industry and factors leading to sluggish and stuck fermentations have been extensively studied and reviewed. The most studied cause of sluggish and stuck fermentation is the nitrogen content limitation. Nevertheless, other factors, such as temperature of fermentation and sugar concentration can affect the growth of yeasts. In this study we modelled the yeast growth‐cycle in wine model system as a function of temperature, sugar and ammonium concentrations; the individual effects and the interaction of these factors were analysed by means of a quadratic response surface methodology. Cell concentrations and weight loss were monitored in the whole wine fermentation process. The results of central composite design show that lower is the availability of nitrogen, higher is the cell growth rate; moreover, initial nitrogen concentration also influences survival time of Saccharomyces cerevisiae. 相似文献
100.
Summary
In this paper thermal behavior of some HNBR blends with CPE, PVC, CR and NBR at three temperatures, 150, 170 and 190°C is
presented. Changes in characteristic IR bands, gel fraction, and chlorine content were assessed. Some mechanistic differences
between the studied systems, regarding the involvement the depletion of chlorine and modification in gel content, were pointed
out. Cyclization of nitrile structure was also observed by means of 2240 cm−1 band ascribed to >C=NH. Kinetic considerations are presented.
Received: 3 June 2002/Revised version: 14 November 2002/ Accepted 20 November 2002
Correspondence to Traian Zaharescu 相似文献