期刊文献+
共找到3篇文章
< 1 >
每页显示 20 50 100
A novel relationship between elastic modulus and void ratio associated with principal stress for coral calcareous sand
1
作者 Ran Gao jianhong ye 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期1033-1048,共16页
Elastic moduli,e.g.shear modulus G and bulk modulus K,are important parameters of geotechnical materials,which are not only the indices for the evaluation of the deformation ability of soils but also the important bas... Elastic moduli,e.g.shear modulus G and bulk modulus K,are important parameters of geotechnical materials,which are not only the indices for the evaluation of the deformation ability of soils but also the important basic parameters for the development of the constitutive models of geotechnical materials.In this study,a series of triaxial loading-unloading-reloading shear tests and isotropic loading-unloadingreloading tests are conducted to study several typical mechanical properties of coral calcareous sand(CCS),and the void ratio evolution during loading,unloading and reloading.The test results show that the stress-strain curves during multiple unloading processes are almost parallel,and their slopes are much greater than the deformation modulus at the initial stage of loading.The relationship between the confining pressure and the volumetric strain can be defined approximately by a hyperbolic equation under the condition of monotonic loading of confining pressure.Under the condition of confining pressure unloading,the evolution of void ratio is linear in the e-lnp0 plane,and these lines are a series of almost parallel lines if there are multiple processes of unloading.Based on the experimental results,it is found that the modified Hardin formulae for the elastic modulus estimation have a significant deviation from the tested values for CCS.Based on the experimental results,it is proposed that the elastic modulus of soils should be determined by the intersection line of two spatial surfaces in the G/K-e-p’/pa space(pa:atmosphere pressure).“Ye formulation”is further proposed for the estimation of the elastic modulus of CCS.This new estimation formulation for soil elastic modulus would provide a new method to accurately describe the mechanical behavior of granular soils. 展开更多
关键词 Coral calcareous sand(CCS) Elastic shear modulus Elastic bulk modulus Triaxial test Estimation formulation Ye formulation
下载PDF
Numerical analysis of bending property of bi-modulus materials and a new method for measurement of tensile elastic modulus
2
作者 Tianmin Wang jianhong ye 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第10期2539-2555,共17页
In nature,there are widely distributed bi-modulus materials with different deformation characteristics under compressive and tensile stress states,such as concrete,rock and ceramics.Due to the lack of constitutive mod... In nature,there are widely distributed bi-modulus materials with different deformation characteristics under compressive and tensile stress states,such as concrete,rock and ceramics.Due to the lack of constitutive model that could reasonably consider the bi-modulus property of materials,and the lack of simple and reliable measurement methods for the tensile elastic parameters of materials,scientists and engineers always neglect the effect of the bi-modulus property of materials in engineering design and numerical simulation.To solve this problem,this study utilizes the uncoupled strain-driven constitutive model proposed by Latorre and Montáns(2020)to systematically study the distributions and magnitudes of stresses and strains of bi-modulus materials in the three-point bending test through the numerical method.Furthermore,a new method to synchronously measure the tensile and compressive elastic moduli of materials through the four-point bending test is proposed.The numerical results show that the bi-modulus property of materials has a significant effect on the stress,strain and displacement in the specimen utilized in the three-point and four-point bending tests.Meanwhile,the results from the numerical tests,in which the elastic constitutive model proposed by Latorre and Montáns(2020)is utilized,also indicate that the newly proposed measurement method has a good reliability.Although the new measurement method proposed in this study can synchronously and effectively measure the tensile and compressive elastic moduli,it cannot measure the tensile and compressive Poisson’s ratios. 展开更多
关键词 Bi-modulus material Uncoupled strain-driven constitutive model Three-point bending test Four-point bending test Tensile elastic modulus FssiCAS
下载PDF
Effects of resistin on insulin signaling in endothelial cells
3
作者 Zhizhen LI Fangping LI +2 位作者 jianhong ye Li YAN Zuzhi FU 《Frontiers of Medicine》 SCIE CSCD 2009年第2期136-140,共5页
The objective of this study was to investigate the effects of resistin on insulin signaling in human umbilical vein endothelial cells(HUVECs).HUVECs were incubated with recombinant human resistin(0–100 ng/mL)for 24 h... The objective of this study was to investigate the effects of resistin on insulin signaling in human umbilical vein endothelial cells(HUVECs).HUVECs were incubated with recombinant human resistin(0–100 ng/mL)for 24 h.Akt and endothelial nitric oxide synthase(eNOS)phosphorylation levels of endothelial cells under basal or insulin stimulated conditions were measured by Western blot.Nitric oxide(NO)production of HUVECs was also detected.The results showed that resistin could significantly inhibit Akt and eNOS phos-phorylation and NO production in endothelial cells under insulin stimulated conditions(P<0.05 vs control).But under basal conditions,treatment with resistin could result in a decrease in eNOS phosphorylation(P<0.05 vs control)but had no effect on NO production and Akt phosphorylation levels.Thesefindings suggested that resistin exerted an inhibitory effect on NO production by inhibiting insulin signaling and eNOS phosphorylation in endothelial cells. 展开更多
关键词 RESISTIN ENDOTHELIUM nitric oxide endothelial nitric oxide synthase Akt-binding protein mouse
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部