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.

CTS-9321887威廉·马什·莱斯大学P.I.：Riki Kobayashi：Riki Kobayashi：Riki Kobayashi发展了一个新的五参数扩展对应态模型，适用于各种碳氢化合物在稠密流体相中的粘度和质子自旋-晶格驰豫速率。简单的混合规则允许将模型扩展到混合物。对于环烷烃和支链烷烃及其与正构烷烃的混合物，该模型对Ely和Hanley 1，2的粘度模型进行了改进。对质子自旋-晶格驰豫速率的对应态处理，得到了饱和烃的自旋-晶格驰豫速率r1与温度之间的新的关联式，跨越了三个不同的自旋驰豫过程(即自旋-旋转、分子内和分子间偶极-偶极机制)。对于纯流体和混合流体，{符号104\f“符号”}之间建立了精确的关联，观测均方根偏差小于8.0%。这种新的方法利用形状因子3来正确地预测p-v-t表面；并利用两个额外的常数来考虑传输。表示粘度的新参数{符号103\f“符号”}和表示R1的新参数{符号98\f“符号”}主要来自多原子分子的受阻旋转。仅利用形状因子3的四参数对应态处理，当限于长链烷烃时，产生了相当精确的关联式。