Spinodal phase separation behavior of poly(methyl methacrylate)/poly(styrene-co-acrylonitrile) (PMMA/SAN) blends was investigated by the time-resolved small angle light scattering (SALS) technique. It was found that t...Spinodal phase separation behavior of poly(methyl methacrylate)/poly(styrene-co-acrylonitrile) (PMMA/SAN) blends was investigated by the time-resolved small angle light scattering (SALS) technique. It was found that the influence of temperature on the scattering intensity evolution followed the time-temperature superposition principle. The relationship between temperature and the relaxation ti me of scattering intensity I(t) can be well described by the Williams-Landel-Ferry (WLF) function.展开更多
Based on the three-dimensional ela stic inclusion model proposed by Dobrovolskii, we developed a three-dimensional rheologic inclusion model and theory to study the earthquake preparation process. By using corresponde...Based on the three-dimensional ela stic inclusion model proposed by Dobrovolskii, we developed a three-dimensional rheologic inclusion model and theory to study the earthquake preparation process. By using correspondence principle in the theory of rheologic mechanics, we derived the analytic expression of the viscoelas-tic displacement at an arbitrary point (x, y, z) in three directions of x, y and z-axes (i. e., U(r, t), V*(r, t) and W(r, t)) produced by a three-dimension inclusion in the semi-infinite rheologic medium defined by the standard linear rheologic model.展开更多
The variational functional of the Hellinger-Reissner variational principle for the large displacement problem of a thin shallow shell with an arbitrary shape is first established. Then the functional of the modified p...The variational functional of the Hellinger-Reissner variational principle for the large displacement problem of a thin shallow shell with an arbitrary shape is first established. Then the functional of the modified principle suitable for the finite element method is derived. In the functional only two independent variables, the deflection w and the stress function F are included. The displacement expressions in the middle surface on the boundary of the shell is also derived by means of the previous two variables.展开更多
Naturally curved and twisted closed thin-walled slender beams of composite material undergoing small strains, large displacements and rotations have been investigated, and an incomplete generalized variational functio...Naturally curved and twisted closed thin-walled slender beams of composite material undergoing small strains, large displacements and rotations have been investigated, and an incomplete generalized variational function on theory of elasticity with finite displacement is established far these beams with complete constrained boundaries at two ends. The balance equations as well as all boundary conditions concerned have been deduced from functional stationary value condition. The above-mentioned method can also be extended to other various incomplete constrained boundaries conveniently. In addition, the fundamental equations and concerned formulas in the small displacement theory of the beams can be derived by using above results.展开更多
Food safety is a major issue to public health and have attracted global attention.Fast,sensitive,and reliable detection methods for food hazardous substances is highly desirable.Aptamers which can bind to the target m...Food safety is a major issue to public health and have attracted global attention.Fast,sensitive,and reliable detection methods for food hazardous substances is highly desirable.Aptamers which can bind to the target molecules with high affinity and specificity represent an attractive tool for the recognition of food hazardous substances,which play an important role in the development and application of new food safety detection technology.But current assays for characterizing small molecule-aptamer binding are limited by either the mass sensitivity or the size differentiation ability.Herein,we proposed a comprehensive method for assessing the dissociation equilibria of small molecule-aptamer,which is immobilized-free under ambient conditions.The design employs the Le Chatelier’s principle and could be used to effectively measure small molecule-aptamer interactions.ATP binding aptamer and anti-aflatoxin B1 aptamer were used as the model system to determine their affinity,in which their dissociation equilibria measurements are in excellent close to their previous work.Due to the simplicity and sensitivity of this new method,we believe that it could be recommended as an effective tool for characterizing small molecule-aptamer interactions and promote the further application of small molecular aptamer in food safety.展开更多
This paper, having made systematic trend analysis on the front and rear segments of Xintan landslide for space and time respectively by using matbematical statistical principles,discovered that there is obvious trend ...This paper, having made systematic trend analysis on the front and rear segments of Xintan landslide for space and time respectively by using matbematical statistical principles,discovered that there is obvious trend displacement Of the monitoring points in the rear margin area of the slope and the rates of trend displacement gradually increase with time whereas there is no trend displacement of the monitoring points in the front margin area. This result suggests that the rear margin area of segment is an area of overall sliding and is transforming towards destabilization whereas the front margin area is an area of relative stability. This analytical result well coincides with the conclusion of evaluation on dynamic stability. The analytical result mentioned above shows that the medium to short term forecast and prediction of slope stability can be made by using trend displacement analysis technique in order to achieve the goal of timely evaluation and prevention.展开更多
In order to study the dynamic performance of the thermosetting epoxy asphalt mixture(EAM), an experimental program on the dynamic modulus E is conducted. First, E of the EAM under different temperatures and frequenc...In order to study the dynamic performance of the thermosetting epoxy asphalt mixture(EAM), an experimental program on the dynamic modulus E is conducted. First, E of the EAM under different temperatures and frequencies are tested through the simple performance test(SPT), and the effects of temperatures and frequencies on the dynamic modulus of the EAM are analyzed. Secondly, the static modulus of the EAM and the dynamic modulus of other two ordinary mixtures are tested and compared to E of the EAM. Finally the dynamic modulus master curve is constructed using the time-temperature superposition principle. The results show that the E values increase with the increase in the test frequency while on the other hand, the E values decrease with the increase in the test temperature. It also can be seen from the results that the dynamic modulus corresponding to the actual vehicle mode is significantly greater than the static modulus, and the dynamic modulus of the EAM is greater than that of SBS mixtures and the common hot mixed asphalt (HMA). The study results can provide a theoretical basis for the design and mechanical analysis of the steel deck pavement.展开更多
基金This work was supported by the Special Funds for Major State Basic Research Projects (Grand G1999064800)
文摘Spinodal phase separation behavior of poly(methyl methacrylate)/poly(styrene-co-acrylonitrile) (PMMA/SAN) blends was investigated by the time-resolved small angle light scattering (SALS) technique. It was found that the influence of temperature on the scattering intensity evolution followed the time-temperature superposition principle. The relationship between temperature and the relaxation ti me of scattering intensity I(t) can be well described by the Williams-Landel-Ferry (WLF) function.
基金Chinese Joint Seismological Science Foundation (101105)
文摘Based on the three-dimensional ela stic inclusion model proposed by Dobrovolskii, we developed a three-dimensional rheologic inclusion model and theory to study the earthquake preparation process. By using correspondence principle in the theory of rheologic mechanics, we derived the analytic expression of the viscoelas-tic displacement at an arbitrary point (x, y, z) in three directions of x, y and z-axes (i. e., U(r, t), V*(r, t) and W(r, t)) produced by a three-dimension inclusion in the semi-infinite rheologic medium defined by the standard linear rheologic model.
文摘The variational functional of the Hellinger-Reissner variational principle for the large displacement problem of a thin shallow shell with an arbitrary shape is first established. Then the functional of the modified principle suitable for the finite element method is derived. In the functional only two independent variables, the deflection w and the stress function F are included. The displacement expressions in the middle surface on the boundary of the shell is also derived by means of the previous two variables.
文摘Naturally curved and twisted closed thin-walled slender beams of composite material undergoing small strains, large displacements and rotations have been investigated, and an incomplete generalized variational function on theory of elasticity with finite displacement is established far these beams with complete constrained boundaries at two ends. The balance equations as well as all boundary conditions concerned have been deduced from functional stationary value condition. The above-mentioned method can also be extended to other various incomplete constrained boundaries conveniently. In addition, the fundamental equations and concerned formulas in the small displacement theory of the beams can be derived by using above results.
基金supported by the National Key R&D Program of China(2017YFC1600603)the Funds for Huangshan Professorship of Hefei University of Technology(407-037019).
文摘Food safety is a major issue to public health and have attracted global attention.Fast,sensitive,and reliable detection methods for food hazardous substances is highly desirable.Aptamers which can bind to the target molecules with high affinity and specificity represent an attractive tool for the recognition of food hazardous substances,which play an important role in the development and application of new food safety detection technology.But current assays for characterizing small molecule-aptamer binding are limited by either the mass sensitivity or the size differentiation ability.Herein,we proposed a comprehensive method for assessing the dissociation equilibria of small molecule-aptamer,which is immobilized-free under ambient conditions.The design employs the Le Chatelier’s principle and could be used to effectively measure small molecule-aptamer interactions.ATP binding aptamer and anti-aflatoxin B1 aptamer were used as the model system to determine their affinity,in which their dissociation equilibria measurements are in excellent close to their previous work.Due to the simplicity and sensitivity of this new method,we believe that it could be recommended as an effective tool for characterizing small molecule-aptamer interactions and promote the further application of small molecular aptamer in food safety.
文摘This paper, having made systematic trend analysis on the front and rear segments of Xintan landslide for space and time respectively by using matbematical statistical principles,discovered that there is obvious trend displacement Of the monitoring points in the rear margin area of the slope and the rates of trend displacement gradually increase with time whereas there is no trend displacement of the monitoring points in the front margin area. This result suggests that the rear margin area of segment is an area of overall sliding and is transforming towards destabilization whereas the front margin area is an area of relative stability. This analytical result well coincides with the conclusion of evaluation on dynamic stability. The analytical result mentioned above shows that the medium to short term forecast and prediction of slope stability can be made by using trend displacement analysis technique in order to achieve the goal of timely evaluation and prevention.
基金Program for New Century Excellent Talents in University (No.NCET-08-0118)Specialized Research Fund for the Doctoral Program of Higher Education(No.20090092110049)
文摘In order to study the dynamic performance of the thermosetting epoxy asphalt mixture(EAM), an experimental program on the dynamic modulus E is conducted. First, E of the EAM under different temperatures and frequencies are tested through the simple performance test(SPT), and the effects of temperatures and frequencies on the dynamic modulus of the EAM are analyzed. Secondly, the static modulus of the EAM and the dynamic modulus of other two ordinary mixtures are tested and compared to E of the EAM. Finally the dynamic modulus master curve is constructed using the time-temperature superposition principle. The results show that the E values increase with the increase in the test frequency while on the other hand, the E values decrease with the increase in the test temperature. It also can be seen from the results that the dynamic modulus corresponding to the actual vehicle mode is significantly greater than the static modulus, and the dynamic modulus of the EAM is greater than that of SBS mixtures and the common hot mixed asphalt (HMA). The study results can provide a theoretical basis for the design and mechanical analysis of the steel deck pavement.