The Effect of Environment on The Fatigue and Fracture Response of Advanced Polymers and Composites

环境对先进聚合物和复合材料疲劳和断裂响应的影响

• 批准号: 9410979
• 负责人: Lisa Pruitt
• 金额: $ 1.8万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-09-01 至 1996-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9410979&HistoricalAwards=false
• 关键词: Effect; Environment; Fatigue; Fracture; Response

ABSTRACT CTS-9321887 William Marsh Rice University P. I.: Riki Kobayashi A new five-parameter extended corresponding states model has been developed for viscosity and proton spin-lattice relaxation rate applicable to a variety of hydrocarbons in the dense fluid phase. Simple mixing rules allows extension of the model to mixtures. This proposed model is shown to bring improvements over the viscosity model of Ely and Hanley 1, 2 , for cyclic and branched alkanes, and their mixtures with n-paraffins. The corresponding states treatment of the proton spin-lattice relaxation rate, R1, yields a new correlation between R1 and temperature for saturated hydrocarbons, spanning three different processes of spin relaxation (i.e. spin-rotation, intramolecular and intermolecular dipole-dipole mechanisms). Accurate correlations between {SYMBOL 104 \f "Symbol"} are generated for pure and mixed fluids, with observed root-mean-square deviations of less than 8.0%. This new approach utilizes shape factors 3 to properly predict p-v-t surfaces; and two additional constants to account for transport. The new parameters, {SYMBOL 103 \f "Symbol"} for viscosity, and {SYMBOL 98 \f "Symbol"} for R1, mainly arise from hindered rotation of polyatomic molecules. The four-parameter corresponding states treatment, utilizing only the shape factors 3 , yields correlations of comparable accuracy, when confined to long-chain alkanes.

摘要 CTS-9321887 威廉·马什·莱斯大学 P. I.：Riki Kobayashi 开发了一种新的五参数扩展对应态模型，用于适用于稠密流体相中各种碳氢化合物的粘度和质子自旋晶格弛豫率。 简单的混合规则允许将模型扩展到混合物。 对于环状烷烃和支链烷烃及其与正链烷烃的混合物，该模型比 Ely 和 Hanley 1, 2 的粘度模型有所改进。 质子自旋晶格弛豫率 R1 的相应状态处理产生了饱和烃的 R1 与温度之间的新相关性，涵盖了自旋弛豫的三种不同过程（即自旋旋转、分子内和分子间偶极-偶极机制）。 针对纯流体和混合流体生成 {SYMBOL 104 \f "Symbol"} 之间的准确相关性，观察到的均方根偏差小于 8.0%。 这种新方法利用形状因子 3 来正确预测 p-v-t 表面；以及两个额外的常数来解释传输。 新的粘度参数 {SYMBOL 103 \f "Symbol"} 和 R1 的 {SYMBOL 98 \f "Symbol"} 主要来自多原子分子的受阻旋转。 当仅限于长链烷烃时，仅利用形状因子 3 的四参数对应状态处理可产生相当精度的相关性。