On the Second Normal Stress Difference of Entangled Polymers.
نویسندگان
چکیده
منابع مشابه
the impact of training on second language writing assessment: a case of raters’ biasedness
چکیده هدف اول این تحقیق بررسی تأثیر آموزش مصحح بر آموزش گیرندگان براساس پایایی نمره های آنها در پنج بخش شامل محتوا ، سازمان ، لغت ، زبان و مکانیک بود. هدف دوم این بود که بدانیم آیا تفاوتهای بین آموزشی گیرندگان زن و مرد در پایایی نمرات آنها وجود دارد. برای بررسی این موارد ، ما 90 دانشجو در سطح میانه (متوسط) که از طریق تست تعیین سطح شده بودند انتخاب شدند. بعد از آنها خواستیم که درباره دو موضوع ا...
15 صفحه اولThe dynamics of entangled polymers
2014 The dynamics of linear chain polymers is studied in concentrated solutions. This paper is based on the « reptation » model of de Gennes, which is a theory of the motion of a polymer in the presence of many topological constraints. Here theoretical and numerical work is presented to extend this theory to include many chain interactions. A theoretical argument is presented that gives the sca...
متن کاملUnexpected power-law stress relaxation of entangled ring polymers.
After many years of intense research, most aspects of the motion of entangled polymers have been understood. Long linear and branched polymers have a characteristic entanglement plateau and their stress relaxes by chain reptation or branch retraction, respectively. In both mechanisms, the presence of chain ends is essential. But how do entangled polymers without ends relax their stress? Using p...
متن کاملStress relaxation in entangled melts of unlinked ring polymers.
Stress relaxation in unlinked ring polymer melts poses an important challenge to our theoretical understanding of entangled polymer dynamics. Recent experiments on entangled unlinked ring melts show power-law stress relaxation with no hint of a rubbery plateau, usually the hallmark of entangled polymers. Here we present a theory for stress relaxation in rings analogous to the successful approac...
متن کاملthe effect of task cognitive complexity and time limit on the performance of the learners with different proficiency levels in second language writing skill
this study investigated the effects of manipulating the cognitive complexity of tasks along +/- few elements and the time limits on l2 learners writing performance. to conduct the study, 60 iranian efl learners with two levels of proficiency, low and high intermediate, were selected and assigned to three groups based on the time devoted to task completion. the participants performed both a simp...
15 صفحه اولذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Nihon Reoroji Gakkaishi
سال: 1999
ISSN: 0387-1533,2186-4586
DOI: 10.1678/rheology.27.251