Triaxial cyclic loading tests have been performed to assess the influence of plastic deformation on inelastic deformational properties of anisotropic argillite with bedding planes which is regarded as a kind of transv...Triaxial cyclic loading tests have been performed to assess the influence of plastic deformation on inelastic deformational properties of anisotropic argillite with bedding planes which is regarded as a kind of transversely isotropic media.Considering argillite's anisotropy and inelastic deformational properties,theoretical formulae for calculating oriented elastic parameters were deduced by the unloading curves,which can be better fitted for the description of its elasticity than loading curves.Test results indicate that with the growth of accumulated plastic,strain,the apparent elastic modulus of argillite decreases in a form of exponential decay function,whereas the apparent Poisson ratio increase in a form of power equation.A ratio of unloading recoverable strain to the total strain increment occurred during a loading cycle is defined to illustrate the characteristic relations between anisotropic coupled elasto-plastic deformation and plastic strain.It is significant to observe that high stress level and plastic history have an inhibiting effect on argillite anisotropy.展开更多
We investigated the role of volatiles in the porous structure of coal samples and the corresponding structural deformations that affect the coals' methane adsorption capacity. For this study, the volatiles in coal we...We investigated the role of volatiles in the porous structure of coal samples and the corresponding structural deformations that affect the coals' methane adsorption capacity. For this study, the volatiles in coal were gradually removed by extraction. Changes in the crystal, textural, and porous structures were identified by means of thermogravimetric analysis, X-ray diffraction, and N2 adsorption/desorption. Changes in the methane adsorption behavior before and after volatile removal were investigated. It was found that changes in methane adsorption could be attributed to volatile-related deformations in the coal's porous structure. Microstructural characterizations indicated that the volatiles could be found in two states within the coal, either trapped in the pores, or cross-linked in the network. The former played an important role in constructing the pore spaces and walls within the coal and affected the accessibility of gases. The latter cross-linked state retained the volatiles within the macromolecular coal structural network. This state affected coal-coal interactions, which was a factor that controlled the crystal structure of coal and contributed to the number of porous deformations.展开更多
The atomic structure and associated deformation behavior of metallic glasses(MGs)have been long standing issues.Although recent computational/experimental results indicate that the structure of MGs is heterogeneous at...The atomic structure and associated deformation behavior of metallic glasses(MGs)have been long standing issues.Although recent computational/experimental results indicate that the structure of MGs is heterogeneous at the nano scale,the fundamental knowledge of the atomic basis for such structural heterogeneity and its impact on the overall properties of MGs is still lacking.We reviewed recent research on unraveling the structure heterogeneity in MGs,with emphases on the use of dynamic atomic force microscopy,the characterization of glass anelasticity by nanoindentation,and the establishment of numerous correlations with structural heterogeneity.展开更多
Configuration-constrained calculations of potential-energy surfaces for ^292 122 show the occurrence of multiquasiparticle high-K isomeric state at oblate superdeformation. Such state could play a unique role in super...Configuration-constrained calculations of potential-energy surfaces for ^292 122 show the occurrence of multiquasiparticle high-K isomeric state at oblate superdeformation. Such state could play a unique role in superheavy nuclei, with possible long life time from enhanced difficulty in fission due to additional barrier at oblate deformation, retardation in a decay due to unpaired nucleons, and hindrance in γ-ray transition due to K forbiddenness.展开更多
基金supported by the National Natural Science Foundation of China(No.52071035)Guangdong Major Project of Basic and Applied Basic Research,China(No.2020B0301030006)。
基金financially supported by the Natural Science Foundation of Chongqing,China(No.cstc2021jcyj-msxm X0433)the Chongqing Foundation of Science and Technology,China(Nos.cstc2020jxjl X0001,cstc2021jxjl50004)the National Natural Science Foundation of China(No.51601154)。
基金Program(2011CB710601) supported by National Basic Research Program of ChinaProject(50925933) supported by National Natural Science Foundation of China+1 种基金Project(2008BAB29B03) supported by National Key Technology Research and Development Program of ChinaProject(2010-122-011) supported by Guizhou Provincial Department of Transportation,China
文摘Triaxial cyclic loading tests have been performed to assess the influence of plastic deformation on inelastic deformational properties of anisotropic argillite with bedding planes which is regarded as a kind of transversely isotropic media.Considering argillite's anisotropy and inelastic deformational properties,theoretical formulae for calculating oriented elastic parameters were deduced by the unloading curves,which can be better fitted for the description of its elasticity than loading curves.Test results indicate that with the growth of accumulated plastic,strain,the apparent elastic modulus of argillite decreases in a form of exponential decay function,whereas the apparent Poisson ratio increase in a form of power equation.A ratio of unloading recoverable strain to the total strain increment occurred during a loading cycle is defined to illustrate the characteristic relations between anisotropic coupled elasto-plastic deformation and plastic strain.It is significant to observe that high stress level and plastic history have an inhibiting effect on argillite anisotropy.
基金supported by the National Basic Research Program of China (2011CB201202)
文摘We investigated the role of volatiles in the porous structure of coal samples and the corresponding structural deformations that affect the coals' methane adsorption capacity. For this study, the volatiles in coal were gradually removed by extraction. Changes in the crystal, textural, and porous structures were identified by means of thermogravimetric analysis, X-ray diffraction, and N2 adsorption/desorption. Changes in the methane adsorption behavior before and after volatile removal were investigated. It was found that changes in methane adsorption could be attributed to volatile-related deformations in the coal's porous structure. Microstructural characterizations indicated that the volatiles could be found in two states within the coal, either trapped in the pores, or cross-linked in the network. The former played an important role in constructing the pore spaces and walls within the coal and affected the accessibility of gases. The latter cross-linked state retained the volatiles within the macromolecular coal structural network. This state affected coal-coal interactions, which was a factor that controlled the crystal structure of coal and contributed to the number of porous deformations.
基金supported by the Research Grant Council(RGC)of the government of Hong Kong through the General Research Fund(Grant No.City U 117612)GRC(Grant No.City U 530711)
文摘The atomic structure and associated deformation behavior of metallic glasses(MGs)have been long standing issues.Although recent computational/experimental results indicate that the structure of MGs is heterogeneous at the nano scale,the fundamental knowledge of the atomic basis for such structural heterogeneity and its impact on the overall properties of MGs is still lacking.We reviewed recent research on unraveling the structure heterogeneity in MGs,with emphases on the use of dynamic atomic force microscopy,the characterization of glass anelasticity by nanoindentation,and the establishment of numerous correlations with structural heterogeneity.
基金Supported by the National Natural Science Foundation of China under Grant No.11205120
文摘Configuration-constrained calculations of potential-energy surfaces for ^292 122 show the occurrence of multiquasiparticle high-K isomeric state at oblate superdeformation. Such state could play a unique role in superheavy nuclei, with possible long life time from enhanced difficulty in fission due to additional barrier at oblate deformation, retardation in a decay due to unpaired nucleons, and hindrance in γ-ray transition due to K forbiddenness.