By bianalytic functions, the boundary integral formula of the stress function for the elastic problem in a circle plane is developed. But this integral formula includes a strongly singular integral and can not be dire...By bianalytic functions, the boundary integral formula of the stress function for the elastic problem in a circle plane is developed. But this integral formula includes a strongly singular integral and can not be directly calculated. After the stress function is expounded to Fourier series, making use of some formulas in generalized functions to the convolutions, the boundary integral formula which does not include strongly singular integral is derived further. Then the stress function can be got simply by the integration of the values of the stress function and its derivative on the boundary. Some examples are given. It shows that the boundary integral formula of the stress function for the elastic problem is convenient.展开更多
After the stress function and the normal derivative on the boundary for the plane problem of exterior circular domain are expanded into Laurent series, comparing them with the Laurent series of the complex stress func...After the stress function and the normal derivative on the boundary for the plane problem of exterior circular domain are expanded into Laurent series, comparing them with the Laurent series of the complex stress function and making use of some formulas in Fourier series and the convolutions, the boundary integral formula of the stress function is derived further. Then the stress function can be obtained directly by the integration of the stress function and its normal derivative on the boundary. Some examples are given. It shows that the boundary integral formula of the stress function is convenient to be used for solving the elastic plane problem of exterior circular domain.展开更多
OBJECTIVE Bushen Yizhi formula,constructed by Prof LIAO Shi-long′research group(Guangzhou University of chinese medicine),is the combination of clinical experience and modern pharmacological research,and mainly focus...OBJECTIVE Bushen Yizhi formula,constructed by Prof LIAO Shi-long′research group(Guangzhou University of chinese medicine),is the combination of clinical experience and modern pharmacological research,and mainly focuses on the etiology and pathogenesis of AD for treating both cause and symptoms.In this research,the pharmacodynamic study protocol of Bushen Yizhi formula was designed according to the characteristics and indications function of herbs in the formula,and was conformed to preclinical pharmacological research of traditional Chinese medicine for AD,The Technical Requirements of Pharmacology and Toxicology Research in New Drug Development Enacted by State Food and Drug administration also was guiding principle.METHODS A preliminary randomized double-blind clinical trail with 141 cases of AD showed that the efficiency of Bushen Yizhi formula was 61.9%and the increased mean of MMSE was 3.17,but the specific mechanism remains unclear.This study was aimed to reveal the preventive and therapeutic effect of Bushen Yizhi formula on AD rats and its related mechanism.In this research,forebrain-injected IBO-induced AD rats(cholinergic neuron lesion),senescence accelerated mouse,scopolamineinduced learning and memory deficiency rats(mild cognitive impairment)were all established.The learning and memory ability was tested with Morris water maze.Then formation of age pigment,extent of neuronal loss,activation of astrocytes,content of NTFs and degree of oxidized stress damage were determined by morphology,mmunohistochemical and molecular biology methods.RESULTS As the application of Bushen Yizhi formula,the learning and memory ability in all three groups were significantly improved,the formation of age pigment and the content of ACH in cortex and hippocampus were reduced,the activation of astrocytes and release of inflammatory factor(TNF-αand IL-1β)were inhibited,and the antioxidases(CAT,SOD,GSH-PX)were up-regulated and MDA was down-regulated.CONCLUSION Bushen Yizhi formula can prevent and treat AD rats,which might be achieved by anti-inflammatory,antioxidant and protecting cholinergic neuron.展开更多
本文针对平面内弯矩作用下的T形圆管相贯节点焊缝处热点应力分布开展研究.利用径向拉伸法建立了T形圆管相贯节点的有限元网格模型,对热点应力分析结果的可靠性进行了网格密度分析和试验对比分析,提出了满足计算精度要求的基本密度网格....本文针对平面内弯矩作用下的T形圆管相贯节点焊缝处热点应力分布开展研究.利用径向拉伸法建立了T形圆管相贯节点的有限元网格模型,对热点应力分析结果的可靠性进行了网格密度分析和试验对比分析,提出了满足计算精度要求的基本密度网格.通过无量纲几何参数分析归纳了热点应力沿相贯线的环向分布规律及几何参数影响规律,发现了冠点波峰分裂现象及分裂过程中波峰曲线的三种变化形态,在此基础上提出了采用以π为周期的系数来修正冠点曲线形状的波形修正方法及分布曲线参数公式.与伦敦大学学院(University College London,UCL)两位学者的公式和试验数据进行对比分析,结果表明本文公式具有更简洁的表达形式和更高的精度.展开更多
The strength of structural loess consists of the shear strength and tensile strength. In this study, the stress path, the failure envelope of principal stress （ Kf line）, and the strength failure envelope of structu...The strength of structural loess consists of the shear strength and tensile strength. In this study, the stress path, the failure envelope of principal stress （ Kf line）, and the strength failure envelope of structurally intact loess and remolded loess were analyzed through three kinds of tests： the tensile strength test, the uniaxial compressive strength test, and the conventional triaxial shear strength test. Then, in order to describe the tensile strength and shear strength of structural loess comprehensively and reasonably, a joint strength formula for structural loess was established. This formula comprehensively considers tensile and shear properties. Studies have shown that the tensile strength exhibits a decreasing trend with increasing water content. When the water content is constant, the tensile strength of the structurally intact soil is greater than that ofremolded soil. In the studies, no loss of the originally cured cohesion in the structurally intact soil samples was observed, given that the soil samples did not experience loading disturbance during the uniaxial compressive strength test, meaning there is a high initial structural strength. The results of the conventional triaxial shear strength test show that the water content is correlated with the strength of the structural loess. When the water content is low, the structural properties are strong, and when the water content is high, the structural properties are weak, which means that the water content and the ambient pressure have significant effects on the stress-strain relationship of structural loess. The established joint strength formula of structural loess effectively avoids overestimating the role of soil tensile strength in the traditional theory of Mohr-Coulomb strength.展开更多
文摘By bianalytic functions, the boundary integral formula of the stress function for the elastic problem in a circle plane is developed. But this integral formula includes a strongly singular integral and can not be directly calculated. After the stress function is expounded to Fourier series, making use of some formulas in generalized functions to the convolutions, the boundary integral formula which does not include strongly singular integral is derived further. Then the stress function can be got simply by the integration of the values of the stress function and its derivative on the boundary. Some examples are given. It shows that the boundary integral formula of the stress function for the elastic problem is convenient.
文摘After the stress function and the normal derivative on the boundary for the plane problem of exterior circular domain are expanded into Laurent series, comparing them with the Laurent series of the complex stress function and making use of some formulas in Fourier series and the convolutions, the boundary integral formula of the stress function is derived further. Then the stress function can be obtained directly by the integration of the stress function and its normal derivative on the boundary. Some examples are given. It shows that the boundary integral formula of the stress function is convenient to be used for solving the elastic plane problem of exterior circular domain.
基金The project supported by National Natural Science Foundation of China(81273817)Shandong Province Natural Science Foundation of China(ZR2013HL062)by Foundation of Overseas Distinguished Taishan Scholars of Shandong Province
文摘OBJECTIVE Bushen Yizhi formula,constructed by Prof LIAO Shi-long′research group(Guangzhou University of chinese medicine),is the combination of clinical experience and modern pharmacological research,and mainly focuses on the etiology and pathogenesis of AD for treating both cause and symptoms.In this research,the pharmacodynamic study protocol of Bushen Yizhi formula was designed according to the characteristics and indications function of herbs in the formula,and was conformed to preclinical pharmacological research of traditional Chinese medicine for AD,The Technical Requirements of Pharmacology and Toxicology Research in New Drug Development Enacted by State Food and Drug administration also was guiding principle.METHODS A preliminary randomized double-blind clinical trail with 141 cases of AD showed that the efficiency of Bushen Yizhi formula was 61.9%and the increased mean of MMSE was 3.17,but the specific mechanism remains unclear.This study was aimed to reveal the preventive and therapeutic effect of Bushen Yizhi formula on AD rats and its related mechanism.In this research,forebrain-injected IBO-induced AD rats(cholinergic neuron lesion),senescence accelerated mouse,scopolamineinduced learning and memory deficiency rats(mild cognitive impairment)were all established.The learning and memory ability was tested with Morris water maze.Then formation of age pigment,extent of neuronal loss,activation of astrocytes,content of NTFs and degree of oxidized stress damage were determined by morphology,mmunohistochemical and molecular biology methods.RESULTS As the application of Bushen Yizhi formula,the learning and memory ability in all three groups were significantly improved,the formation of age pigment and the content of ACH in cortex and hippocampus were reduced,the activation of astrocytes and release of inflammatory factor(TNF-αand IL-1β)were inhibited,and the antioxidases(CAT,SOD,GSH-PX)were up-regulated and MDA was down-regulated.CONCLUSION Bushen Yizhi formula can prevent and treat AD rats,which might be achieved by anti-inflammatory,antioxidant and protecting cholinergic neuron.
文摘本文针对平面内弯矩作用下的T形圆管相贯节点焊缝处热点应力分布开展研究.利用径向拉伸法建立了T形圆管相贯节点的有限元网格模型,对热点应力分析结果的可靠性进行了网格密度分析和试验对比分析,提出了满足计算精度要求的基本密度网格.通过无量纲几何参数分析归纳了热点应力沿相贯线的环向分布规律及几何参数影响规律,发现了冠点波峰分裂现象及分裂过程中波峰曲线的三种变化形态,在此基础上提出了采用以π为周期的系数来修正冠点曲线形状的波形修正方法及分布曲线参数公式.与伦敦大学学院(University College London,UCL)两位学者的公式和试验数据进行对比分析,结果表明本文公式具有更简洁的表达形式和更高的精度.
基金supported by the National Natural Science Foundation of China(Grant No.11072193)the Fundamental Research Funds for the Central Universities(Grant No.2013G1502009)the China Postdoctoral Science Foundation(Grant No.20100481354)
文摘The strength of structural loess consists of the shear strength and tensile strength. In this study, the stress path, the failure envelope of principal stress （ Kf line）, and the strength failure envelope of structurally intact loess and remolded loess were analyzed through three kinds of tests： the tensile strength test, the uniaxial compressive strength test, and the conventional triaxial shear strength test. Then, in order to describe the tensile strength and shear strength of structural loess comprehensively and reasonably, a joint strength formula for structural loess was established. This formula comprehensively considers tensile and shear properties. Studies have shown that the tensile strength exhibits a decreasing trend with increasing water content. When the water content is constant, the tensile strength of the structurally intact soil is greater than that ofremolded soil. In the studies, no loss of the originally cured cohesion in the structurally intact soil samples was observed, given that the soil samples did not experience loading disturbance during the uniaxial compressive strength test, meaning there is a high initial structural strength. The results of the conventional triaxial shear strength test show that the water content is correlated with the strength of the structural loess. When the water content is low, the structural properties are strong, and when the water content is high, the structural properties are weak, which means that the water content and the ambient pressure have significant effects on the stress-strain relationship of structural loess. The established joint strength formula of structural loess effectively avoids overestimating the role of soil tensile strength in the traditional theory of Mohr-Coulomb strength.
