The manufacturing process of CaCO3 modified Polypropylene (PP) spun-bonded nonwovens was studied. Then the effect of the additive amount of CaCO3 on mechanical properties of the product was analyzed, and a compatible ...The manufacturing process of CaCO3 modified Polypropylene (PP) spun-bonded nonwovens was studied. Then the effect of the additive amount of CaCO3 on mechanical properties of the product was analyzed, and a compatible mechanism between CaCO3 particles and the main component of PP was established. In the end, the mechanical performance of the products was studied when the natural light degradation was changed. The experiment results show that after adding CaCO3 to the PP spun-bonded nonwovens and through the application of complex coupling agent and organic modification, hardcore of rigid particles and polymer composite elastomers can be combined together tightly and disperse rapidly and evenly in the main part of PP. In addition, CaCO3 can catalyze the light degradation of PP spun-bonded nonwovens. The larger the content of CaCO3 is, the faster the light degradation will be.展开更多
The nation can be broken down into two categories： ＂ancient nations＂ and ＂modern nations.＂ The ancient Huaxia nation went through two phases in the course of its formation： the self-existent nation and the self-...The nation can be broken down into two categories： ＂ancient nations＂ and ＂modern nations.＂ The ancient Huaxia nation went through two phases in the course of its formation： the self-existent nation and the self-aware nation. The reason the self-existent Huaxia nation1 arose in the Xia and Shang period lies in its unified yet diverse composite state structure that could encompass a variety of buzu within the framework of a dynastic state. The pre-Xia Five Emperors period saw the genesis of the Huaxia nation. During this period, different buzu states were cemented into a diverse yet unified nation-state through a confederation of chiefdoms.展开更多
In this article, the composite π-joint is investigated under bending loads. The ＂L＂ preform is the critical component regard- ing composite π-joint failure. The study is presented in the failure detection of a car...In this article, the composite π-joint is investigated under bending loads. The ＂L＂ preform is the critical component regard- ing composite π-joint failure. The study is presented in the failure detection of a carbon fiber composite π-joint structure under bending loads using fiber Bragg grating （FBG） sensor. Firstly, based on the general f＇mite element method （FEM） software, the 3-D finite element （FE） model of composite π-joint is established, and the failure process and every lamina failure load of composite π-joint are investigated by maximum stress criteria. Then, strain distributions along the length of FBG are extracted, and the reflection spectra of FBG are calculated according to the strain distribution. Finally, to verify the numerical results, a test scheme is performed and the experimental spectra of FBG are recorded. The experimental results indicate that the failure sequence and the corresponding critical loads of failure are consistent with the numerical predictions, and the computational error of failure load is less than 6.4%. Furthermore, it also verifies the feasibility of the damage detection system.展开更多
文摘The manufacturing process of CaCO3 modified Polypropylene (PP) spun-bonded nonwovens was studied. Then the effect of the additive amount of CaCO3 on mechanical properties of the product was analyzed, and a compatible mechanism between CaCO3 particles and the main component of PP was established. In the end, the mechanical performance of the products was studied when the natural light degradation was changed. The experiment results show that after adding CaCO3 to the PP spun-bonded nonwovens and through the application of complex coupling agent and organic modification, hardcore of rigid particles and polymer composite elastomers can be combined together tightly and disperse rapidly and evenly in the main part of PP. In addition, CaCO3 can catalyze the light degradation of PP spun-bonded nonwovens. The larger the content of CaCO3 is, the faster the light degradation will be.
基金part of the fruits of the National Key Program for Social Sciences on"Theories and Methodologies in Research on the Origins of China"(Grant No.:12&ZD133) in 2012funded by Shanghai Higher Education’s Connotation Construction Project("085 Project") of Sociology
文摘The nation can be broken down into two categories： ＂ancient nations＂ and ＂modern nations.＂ The ancient Huaxia nation went through two phases in the course of its formation： the self-existent nation and the self-aware nation. The reason the self-existent Huaxia nation1 arose in the Xia and Shang period lies in its unified yet diverse composite state structure that could encompass a variety of buzu within the framework of a dynastic state. The pre-Xia Five Emperors period saw the genesis of the Huaxia nation. During this period, different buzu states were cemented into a diverse yet unified nation-state through a confederation of chiefdoms.
基金supported by the National High Technology Research and Development Program of China (No.2007AA03Z117)the Key Program of National Natural Science of China (No.50830201)the Ph.D. Teacher,s Research Project of Xuzhou Normal University
文摘In this article, the composite π-joint is investigated under bending loads. The ＂L＂ preform is the critical component regard- ing composite π-joint failure. The study is presented in the failure detection of a carbon fiber composite π-joint structure under bending loads using fiber Bragg grating （FBG） sensor. Firstly, based on the general f＇mite element method （FEM） software, the 3-D finite element （FE） model of composite π-joint is established, and the failure process and every lamina failure load of composite π-joint are investigated by maximum stress criteria. Then, strain distributions along the length of FBG are extracted, and the reflection spectra of FBG are calculated according to the strain distribution. Finally, to verify the numerical results, a test scheme is performed and the experimental spectra of FBG are recorded. The experimental results indicate that the failure sequence and the corresponding critical loads of failure are consistent with the numerical predictions, and the computational error of failure load is less than 6.4%. Furthermore, it also verifies the feasibility of the damage detection system.
