The high strength and stability of the full-lamellar structure guarantee the industrial application of theβ-solidifyingγ-TiAl alloys.However,it is a huge challenge to design an alloy with good hot-deformability as w...The high strength and stability of the full-lamellar structure guarantee the industrial application of theβ-solidifyingγ-TiAl alloys.However,it is a huge challenge to design an alloy with good hot-deformability as well as the full-lamellar structure.The low-cost Ti-42.5Al-2Mn-0.4Mo-0.1B-0.1C(at.%)alloy was designed,which undergoes bothβandαsingle-phase region during the solidification.It is found that the full-lamellar structure can be obtained by the solution heat treatment at 1230℃ for 20 min and then aging treatment at 800℃ for 3 h.Interestingly,a new microstructure,namely,the pearlitic-like microstructure(PM)induced by theα_(2)/γ→βo+γcellular reaction was observed when the aging temperature is increased to above 800℃.The volume fraction of the PM is gradually increased from 0%to 25.5%,65%,and 94%according to elevated aging temperature from 800 to 900,1000,and 1050℃,respectively.The mechanism of the reducedα_(2)/γlamellae and PM formation was discussed regarding the heterogeneous distribution ofβstabilizing elements and the interface energy stored inα_(2)/γlamellae.展开更多
Columnar jointed rock mass(CJRM)combines and mosaic of slender rock columns with different height-to-width(H/W)ratios.Revealing the correlation of the mechanical behavior of individual rock columns with internal facto...Columnar jointed rock mass(CJRM)combines and mosaic of slender rock columns with different height-to-width(H/W)ratios.Revealing the correlation of the mechanical behavior of individual rock columns with internal factors(H/W ratio and material strength)and external factor(lateral pressure)is fundamental to understanding the deterioration of CJRM.We adopt a numerical scheme that combines a statistical meso-damage constitutive model with a finite element formulation based on finite deformation,which can simultaneously consider both material failure and structural instability of the rock columns.Compression tests of rock columns with different H/W ratios and material strengths under varying lateral pressures were conducted to analyze the macro-strength features and failure modes.The numerical results show that increasing the material strength can improve the macro-strength,while the effect of H/W ratio is the opposite.Both increases can promote the conversion of failure modes,and the evolution process is as follows:material failure-induced structural instability→synergy and competition between material failure and structural instability→structural instability-induced material failure.Notably,for the last failure mode,an increase in lateral pressure decreases the macro-strength of the rock column and heightens its instability risk.This finding provides new insights into the response of rocks with different H/W ratios under lateral pressure,extending beyond traditional material-based perspectives.According to the position of the failure mode demarcation line,the failure mode of the rock column can be regulated.展开更多
Characterizing the complex two-phase hydrodynamics in structured packed columns requires a power- ful modeling tool. The traditional two-dimensional model exhibits limitations when one attempts to model the de- tailed...Characterizing the complex two-phase hydrodynamics in structured packed columns requires a power- ful modeling tool. The traditional two-dimensional model exhibits limitations when one attempts to model the de- tailed two-phase flow inside the columns. The present paper presents a three-dimensional computational fluid dy- namics （CFD） model to simulate the two-phase flow in a representative unit of the column. The unit consists of an CFD calculations on column packed with Flexipak 1Y were implemented within the volume of fluid （VOF） mathe- matical framework. The CFD model was validated by comparing the calculated thickness of liquid film with the available experimental data. Special attention was given to quantitative analysis of the effects of gravity on the hy- drodynamics. Fluctuations in the liquid mass flow rate and the calculated pressure drop loss were found to be quali- tatively in agreement with the experimental observations.展开更多
Most reinforced concrete(RC)frame structures did not achieve the "strong column-weak beam" failure mode in recent big earthquakes, resulting in a large number of casualties and significant property loss. To ...Most reinforced concrete(RC)frame structures did not achieve the "strong column-weak beam" failure mode in recent big earthquakes, resulting in a large number of casualties and significant property loss. To deal with this serious problem, a new column-beam relative factor was proposed to characterize the relative yield situation of column ends and beam ends. By limiting the column-beam relative factor, RC frame structures could achieve the "strong column-weak beam" failure mode under the excitation of strong ground motions. The limit values of column-beam relative factor were calculated, analyzed and verified by using structural simulation models for corner columns in the bottom story of structures, which are destroyed most seriously in earthquakes. The results show that the limit values should be analyzed under bi-directional ground motion and with different axial compression ratios of columns. The peak ground acceleration(PGA)of ground motions has no significant effect on the limit values, while the type of strong ground motions has a significant effect on the limit values.展开更多
The purpose of this paper is to discuss the suitability of out-of-codes tall slab-column and shearwall structure and to popularize the structure in seismic region.In the research,flat-plate floor was used in slab-colu...The purpose of this paper is to discuss the suitability of out-of-codes tall slab-column and shearwall structure and to popularize the structure in seismic region.In the research,flat-plate floor was used in slab-column and shearwall structure in the practical engineering,the key parameters of slab-column and shearwall structure and frame-shearwall structure such as deflection,punching shear behavior,story drift and capability curve were worked out by static plastic analysis,elastic-plastic time history analysis and pushover analysis,then the suitability of out-of-codes tall slab-column and shearwall structure was evaluated.The results show that the out-of-codes tall slab-column and shearwall structure studies could satisfy the require of deflection and punching shear behavior,the story drift under 7 degree expected rare earthquake waves could satisfy the limit value in the codes and the seismic design spectrum was crossed by the capability curve of the structure and the structure could not collapse.The conclusion is that slab-column and shearwall structure with reasonable design built in Ⅱ soil site of intensity 7 seismic fortification zone can be designed higher than the limit height in the codes.展开更多
The steel beam-concrete column(RCS)frame structure is composed of the reinforced concrete columns and the steel beams,which is a composite structure with the superior performances.This kind of the frame structure has ...The steel beam-concrete column(RCS)frame structure is composed of the reinforced concrete columns and the steel beams,which is a composite structure with the superior performances.This kind of the frame structure has been rapidly developed and widely used in the field of the civil engineering because of its high building applicability,the fast construction speed,the low cost of the foundation and the good mechanical properties.Various kinds of the large-span,heavy-load and high-rise buildings emerge in endlessly,and the requirement for the structural performance is becoming higher and higher.The reinforced concrete column-steel beam composite frame structure is a high-performance structural system with the broad development prospects in China because of its good mechanical performance,durability,fire resistance and the building use space.展开更多
Enhanced boiling experiments of two different enhanced structures were carried out in a thermosyphon loop evaporator chamber. One was micro-columns array structure (MCAS), which was fabricated on copper plate surface ...Enhanced boiling experiments of two different enhanced structures were carried out in a thermosyphon loop evaporator chamber. One was micro-columns array structure (MCAS), which was fabricated on copper plate surface with interaction high speed wire electrode discharge machining (HS-WEDM). The other was the ramification of MCAS, named micro-column-array and sintered-copper compound structure (MSCS), which was fabricated with sintered method on micro-column array structure. Considering the wall superheat and critical heat flux (CHF), comparisons were made between them. The results show that both MCAS and MSCS can enhance the boiling heat transfer. It is also found that the enhanced boiling heat transfer ability of MSCS is changed obviously while the porosity of the sintered copper layer is changed.展开更多
Based on the assumption of finite deformation, the Hamilton variational principle is extended to a nonlinear elastic Euler-type beam-column structure located on a nonlinear elastic foundation. The corresponding three-...Based on the assumption of finite deformation, the Hamilton variational principle is extended to a nonlinear elastic Euler-type beam-column structure located on a nonlinear elastic foundation. The corresponding three-dimensional （3D） mathematical model for analyzing the nonlinear mechanical behaviors of structures is established, in which the effects of the rotation inertia and the nonlinearity of material and geometry are considered. As an application, the nonlinear stability and the post-buckling for a linear elastic beam with the equal cross-section located on an elastic foundation are analyzed. One end of the beam is fully fixed, and the other end is partially fixed and subjected to an axial force. A new numerical technique is proposed to calculate the trivial solution, bifurcation points, and bifurcation solutions by the shooting method and the Newton- Raphson iterative method. The first and second bifurcation points and the corresponding bifurcation solutions are calculated successfully. The effects of the foundation resistances and the inertia moments on the bifurcation points are considered.展开更多
[Objective] The large-scale single-column fattening pig house with fermen- tation bed could hold 1 500 heads of fattening pigs. Since the number of pigs in piggery is too large, the management is difficult. The behavi...[Objective] The large-scale single-column fattening pig house with fermen- tation bed could hold 1 500 heads of fattening pigs. Since the number of pigs in piggery is too large, the management is difficult. The behavior of feeding, drinking, movement, sleeping, fighting of pigs is difficult to handle. The pigs cannot be man- aged well, resulting in the enhanced weakness of piglets, enhanced illness of weak pigs and missing treatment of ill pigs. The management for the pig populations is not satisfactory, and thus, it is needed to improve timely. [Method] The barriers for the fattening pigs in the large-scale pig house with fermentation bed were designed. The single management for single fattening pig was proposed. The large-scale fat- tening pig house was divided into 8 regions. Among them, 4 regions were located in both sides of the fermentation bed. Their main function was to separate ill, weak, small and bad pigs. In addition, the main column was divided into 4 gradual barri- ers. They were used to separate different-size fattening pigs. In view of manage- ment, the different-type pigs were managed dividedly with the gradual barriers. The equally-sized pigs were concentrated into one column. The ill, weak, small and bad pigs were isolated into barriers. Thus, the dynamic management was adopted. Until the fattening pigs grew up to 75 kg and their health was stable, the barriers among the columns were canceled to mix the pigs again and guarantee the pigs more gymnastic space. [Result] This design would improve the disease resistance of ill pigs, health status of weak pigs and management level of pig populations. This study would also provide a basis for the healthy running of large-scale fattening pig house with fermentation bed. [Conclusion] The pig-raising model with fermentation bed would improve the environment of pig house and the welfare of pigs. In addi- tion, the performance of pigs and quality of pork were also improved. The fermen- tation bed had an obvious advantage in safety and economics, and it had a broad application prospect.展开更多
[Objective] This study aimed to predict the structure of protein OmpH from Pasteurella multocida C47-8 （PmC47-8） strain of yak. [Method] Online BLAST, signal peptide prediction, secondary structure prediction and pr...[Objective] This study aimed to predict the structure of protein OmpH from Pasteurella multocida C47-8 （PmC47-8） strain of yak. [Method] Online BLAST, signal peptide prediction, secondary structure prediction and protein characteristics of sequencing result of gene OmpH from PmC47-8 strain were analyzed. [Result] The similarities of gene OmpH from PmC47-8 with the published 81 OmpH genes were between 84% and 99%; a signal peptide was found with the cleavage sites between 20 and 21 in the polypeptide; secondary structure prediction showed that folding structure accounted for 49.8% and loop structure for 50.2%; it predicted that there were 7 O-glycosylation sites in OmpH protein with the amino acid residual sites of 2, 45, 48, 330, 716, 721, 723, respectively, and 2 N-glycosylation sites with the amino acid residual sites of 15 and 35. [Conclusion] This study lays the foundation for the study on the immunity of OmpH gene from yak.展开更多
The recently proposed mega-sub controlled structure （MSCS）, a new type of structure associated with the design and construction of super-tall buildings, has attracted the attention of designers for use in enhancing ...The recently proposed mega-sub controlled structure （MSCS）, a new type of structure associated with the design and construction of super-tall buildings, has attracted the attention of designers for use in enhancing the control effectiveness in mega-frame buildings. In this paper, a dynamic equation and method to assemble parameter matrixes for a mega-sub controlled structure under random wind loads is presented. Semi-active control using magnetorheological dampers for the MSCS under random wind loads is investigated, and is compared with a corresponding system without dampers. A parametric study of the relative stiffness ratio and relative mass ratio between the mega-frame and the substructures, as well as the additional column stiffness ratio that influences the response control effectiveness of the MSCS, is discussed. The studies reveal, for the first time, that different control mechanisms exist. The results indicate that the proposed structure employing semi-active control can offer an effective control mechanism. Guidelines for selecting parameters are provided based on the analytical study.展开更多
In this paper, the control performance is investigated of Circular Tuned Liquid Column Dampers (CTLCD) over torsional response of offshore platform structures excited by ground motions. Based on the equation of motion...In this paper, the control performance is investigated of Circular Tuned Liquid Column Dampers (CTLCD) over torsional response of offshore platform structures excited by ground motions. Based on the equation of motion for the CTLCD-structure system, the optimal control parameters of CTLCD are given through some derivations on the supposition that the ground motion is a stochastic process. The influence of systematic parameters on the equivalent damping ratio of the structures is analyzed with purely torsional vibration and translational-torsional coupled vibration, respectively. The results show that the Circular Tuned Liquid Column Damper (CTLCD) is an effective torsional response control device.展开更多
An oblique detonation wave for a Mach 7 inlet flow over a long enough wedge of 30 turning angle is simulated numerically using Euler equation and one-step rection model.The fifth-order WENO scheme is adopted to captur...An oblique detonation wave for a Mach 7 inlet flow over a long enough wedge of 30 turning angle is simulated numerically using Euler equation and one-step rection model.The fifth-order WENO scheme is adopted to capture the shock wave.The numerical results show that with the compression of the wedge wall the detonation wave front structure is divided into three sections：the ZND model-like strcuture,single-sided triple point structure and dual-headed triple point strucuture.The first structure is the smooth straight,and the second has the characteristic of the triple points propagating dowanstream only with the same velocity,while the dual-headed triple point structure is very complicated.The detonation waves facing upstream and downstream propagate with different velocities,in which the periodic collisions of the triple points cause the oscillation of the detonation wave front.This oscillation process has temporal and spatial periodicity.In addition,the triple point trace are recorded to obtain different cell structures in three sections.展开更多
The continental margin of Northeast China and its adjacent areas is composed of two tectonic belts. The inner belt is a collage made up of fragments resulting from breakup of an old land with the north part related to...The continental margin of Northeast China and its adjacent areas is composed of two tectonic belts. The inner belt is a collage made up of fragments resulting from breakup of an old land with the north part related to the evolution of the Palaeo-Asian Ocean and the south part to the evolution of the Palaeo - Pacific Ocean. The outer belt is a Mesozoic terrane, which is a melange made up of fragments of the Late Palaeozoic to Early Mesozoic oceanic crust and the Late M esozoic trench accumulations.There existed another ocean-the Palaeo - Pacific Ocean during the period from the closing of the Palaeo-Asian Ocean to the opening of the modern Pacific Ocean or from the Devonian to Jurassic, and the ocean-floor spreading of the Palaeo - Pacific Ocean led to the formation of the above-mentioned tectonic belts. The development of the strike-slip fault system after the Late Jurassic and the formation of an epicontinental volcano -plutonic rock belt in the Late Cretaceous to Early Tertiary are attributed to the interaction between the modern Pacific plate and the Eurasian plate.展开更多
基金the Jihua Laboratory Scientific Research Project(No.X210291TL210)the National Natural Science Foundation of China(No.51971215).
文摘The high strength and stability of the full-lamellar structure guarantee the industrial application of theβ-solidifyingγ-TiAl alloys.However,it is a huge challenge to design an alloy with good hot-deformability as well as the full-lamellar structure.The low-cost Ti-42.5Al-2Mn-0.4Mo-0.1B-0.1C(at.%)alloy was designed,which undergoes bothβandαsingle-phase region during the solidification.It is found that the full-lamellar structure can be obtained by the solution heat treatment at 1230℃ for 20 min and then aging treatment at 800℃ for 3 h.Interestingly,a new microstructure,namely,the pearlitic-like microstructure(PM)induced by theα_(2)/γ→βo+γcellular reaction was observed when the aging temperature is increased to above 800℃.The volume fraction of the PM is gradually increased from 0%to 25.5%,65%,and 94%according to elevated aging temperature from 800 to 900,1000,and 1050℃,respectively.The mechanism of the reducedα_(2)/γlamellae and PM formation was discussed regarding the heterogeneous distribution ofβstabilizing elements and the interface energy stored inα_(2)/γlamellae.
基金supported in part by the National Natural Science Foundation of China(4227233052079019)+1 种基金the Liaoning Province Science and Technology Plan Joint Program(Applied Basic Research Project)(2023JH2/101700340)the Fundamental Research Funds for the Central Universities(DUT24ZD135).
文摘Columnar jointed rock mass(CJRM)combines and mosaic of slender rock columns with different height-to-width(H/W)ratios.Revealing the correlation of the mechanical behavior of individual rock columns with internal factors(H/W ratio and material strength)and external factor(lateral pressure)is fundamental to understanding the deterioration of CJRM.We adopt a numerical scheme that combines a statistical meso-damage constitutive model with a finite element formulation based on finite deformation,which can simultaneously consider both material failure and structural instability of the rock columns.Compression tests of rock columns with different H/W ratios and material strengths under varying lateral pressures were conducted to analyze the macro-strength features and failure modes.The numerical results show that increasing the material strength can improve the macro-strength,while the effect of H/W ratio is the opposite.Both increases can promote the conversion of failure modes,and the evolution process is as follows:material failure-induced structural instability→synergy and competition between material failure and structural instability→structural instability-induced material failure.Notably,for the last failure mode,an increase in lateral pressure decreases the macro-strength of the rock column and heightens its instability risk.This finding provides new insights into the response of rocks with different H/W ratios under lateral pressure,extending beyond traditional material-based perspectives.According to the position of the failure mode demarcation line,the failure mode of the rock column can be regulated.
基金Supported by the Major State Basic Research Development Program of China(2011CB706501)the National Natural Science Foundation of China(51276157)
文摘Characterizing the complex two-phase hydrodynamics in structured packed columns requires a power- ful modeling tool. The traditional two-dimensional model exhibits limitations when one attempts to model the de- tailed two-phase flow inside the columns. The present paper presents a three-dimensional computational fluid dy- namics （CFD） model to simulate the two-phase flow in a representative unit of the column. The unit consists of an CFD calculations on column packed with Flexipak 1Y were implemented within the volume of fluid （VOF） mathe- matical framework. The CFD model was validated by comparing the calculated thickness of liquid film with the available experimental data. Special attention was given to quantitative analysis of the effects of gravity on the hy- drodynamics. Fluctuations in the liquid mass flow rate and the calculated pressure drop loss were found to be quali- tatively in agreement with the experimental observations.
基金Supported by the National Natural Science Foundation of China(No.51525803)the Scientific and Technological Development Plans of Tianjin Construction System(No.2013-35)+1 种基金International Science&Technology Cooperation Program of China(No.2012DFA70810)the Basic Science Research Foundation of IEM,CEA(No.2013B07)
文摘Most reinforced concrete(RC)frame structures did not achieve the "strong column-weak beam" failure mode in recent big earthquakes, resulting in a large number of casualties and significant property loss. To deal with this serious problem, a new column-beam relative factor was proposed to characterize the relative yield situation of column ends and beam ends. By limiting the column-beam relative factor, RC frame structures could achieve the "strong column-weak beam" failure mode under the excitation of strong ground motions. The limit values of column-beam relative factor were calculated, analyzed and verified by using structural simulation models for corner columns in the bottom story of structures, which are destroyed most seriously in earthquakes. The results show that the limit values should be analyzed under bi-directional ground motion and with different axial compression ratios of columns. The peak ground acceleration(PGA)of ground motions has no significant effect on the limit values, while the type of strong ground motions has a significant effect on the limit values.
文摘The purpose of this paper is to discuss the suitability of out-of-codes tall slab-column and shearwall structure and to popularize the structure in seismic region.In the research,flat-plate floor was used in slab-column and shearwall structure in the practical engineering,the key parameters of slab-column and shearwall structure and frame-shearwall structure such as deflection,punching shear behavior,story drift and capability curve were worked out by static plastic analysis,elastic-plastic time history analysis and pushover analysis,then the suitability of out-of-codes tall slab-column and shearwall structure was evaluated.The results show that the out-of-codes tall slab-column and shearwall structure studies could satisfy the require of deflection and punching shear behavior,the story drift under 7 degree expected rare earthquake waves could satisfy the limit value in the codes and the seismic design spectrum was crossed by the capability curve of the structure and the structure could not collapse.The conclusion is that slab-column and shearwall structure with reasonable design built in Ⅱ soil site of intensity 7 seismic fortification zone can be designed higher than the limit height in the codes.
文摘The steel beam-concrete column(RCS)frame structure is composed of the reinforced concrete columns and the steel beams,which is a composite structure with the superior performances.This kind of the frame structure has been rapidly developed and widely used in the field of the civil engineering because of its high building applicability,the fast construction speed,the low cost of the foundation and the good mechanical properties.Various kinds of the large-span,heavy-load and high-rise buildings emerge in endlessly,and the requirement for the structural performance is becoming higher and higher.The reinforced concrete column-steel beam composite frame structure is a high-performance structural system with the broad development prospects in China because of its good mechanical performance,durability,fire resistance and the building use space.
基金Projects(50605023 50436010) supported by the National Natural Science Foundation of China
文摘Enhanced boiling experiments of two different enhanced structures were carried out in a thermosyphon loop evaporator chamber. One was micro-columns array structure (MCAS), which was fabricated on copper plate surface with interaction high speed wire electrode discharge machining (HS-WEDM). The other was the ramification of MCAS, named micro-column-array and sintered-copper compound structure (MSCS), which was fabricated with sintered method on micro-column array structure. Considering the wall superheat and critical heat flux (CHF), comparisons were made between them. The results show that both MCAS and MSCS can enhance the boiling heat transfer. It is also found that the enhanced boiling heat transfer ability of MSCS is changed obviously while the porosity of the sintered copper layer is changed.
基金Project supported by the National Science Foundation for Distinguished Young Scholars of China(No. 11002084)the Shanghai Pujiang Program (No. 07pj14073)the Scientific Research Projectof Shanghai Normal University (No. SK201032)
文摘Based on the assumption of finite deformation, the Hamilton variational principle is extended to a nonlinear elastic Euler-type beam-column structure located on a nonlinear elastic foundation. The corresponding three-dimensional （3D） mathematical model for analyzing the nonlinear mechanical behaviors of structures is established, in which the effects of the rotation inertia and the nonlinearity of material and geometry are considered. As an application, the nonlinear stability and the post-buckling for a linear elastic beam with the equal cross-section located on an elastic foundation are analyzed. One end of the beam is fully fixed, and the other end is partially fixed and subjected to an axial force. A new numerical technique is proposed to calculate the trivial solution, bifurcation points, and bifurcation solutions by the shooting method and the Newton- Raphson iterative method. The first and second bifurcation points and the corresponding bifurcation solutions are calculated successfully. The effects of the foundation resistances and the inertia moments on the bifurcation points are considered.
基金Supported by International Science and Technology Cooperation Project of China(2012DFA31120)Special Fund for Agro-scientific Research in the Public Interest(201303094)National Key Technology Research and Development Program(2012BAD14B15)~~
文摘[Objective] The large-scale single-column fattening pig house with fermen- tation bed could hold 1 500 heads of fattening pigs. Since the number of pigs in piggery is too large, the management is difficult. The behavior of feeding, drinking, movement, sleeping, fighting of pigs is difficult to handle. The pigs cannot be man- aged well, resulting in the enhanced weakness of piglets, enhanced illness of weak pigs and missing treatment of ill pigs. The management for the pig populations is not satisfactory, and thus, it is needed to improve timely. [Method] The barriers for the fattening pigs in the large-scale pig house with fermentation bed were designed. The single management for single fattening pig was proposed. The large-scale fat- tening pig house was divided into 8 regions. Among them, 4 regions were located in both sides of the fermentation bed. Their main function was to separate ill, weak, small and bad pigs. In addition, the main column was divided into 4 gradual barri- ers. They were used to separate different-size fattening pigs. In view of manage- ment, the different-type pigs were managed dividedly with the gradual barriers. The equally-sized pigs were concentrated into one column. The ill, weak, small and bad pigs were isolated into barriers. Thus, the dynamic management was adopted. Until the fattening pigs grew up to 75 kg and their health was stable, the barriers among the columns were canceled to mix the pigs again and guarantee the pigs more gymnastic space. [Result] This design would improve the disease resistance of ill pigs, health status of weak pigs and management level of pig populations. This study would also provide a basis for the healthy running of large-scale fattening pig house with fermentation bed. [Conclusion] The pig-raising model with fermentation bed would improve the environment of pig house and the welfare of pigs. In addi- tion, the performance of pigs and quality of pork were also improved. The fermen- tation bed had an obvious advantage in safety and economics, and it had a broad application prospect.
基金Supported by the Project for High-level Talents of Qinghai University (2008-QGC-7)~~
文摘[Objective] This study aimed to predict the structure of protein OmpH from Pasteurella multocida C47-8 （PmC47-8） strain of yak. [Method] Online BLAST, signal peptide prediction, secondary structure prediction and protein characteristics of sequencing result of gene OmpH from PmC47-8 strain were analyzed. [Result] The similarities of gene OmpH from PmC47-8 with the published 81 OmpH genes were between 84% and 99%; a signal peptide was found with the cleavage sites between 20 and 21 in the polypeptide; secondary structure prediction showed that folding structure accounted for 49.8% and loop structure for 50.2%; it predicted that there were 7 O-glycosylation sites in OmpH protein with the amino acid residual sites of 2, 45, 48, 330, 716, 721, 723, respectively, and 2 N-glycosylation sites with the amino acid residual sites of 15 and 35. [Conclusion] This study lays the foundation for the study on the immunity of OmpH gene from yak.
基金Science and Technology Fund of NWPU Under Grant No. M450211Seed Fund of NWPU Under Grant No. Z200534
文摘The recently proposed mega-sub controlled structure （MSCS）, a new type of structure associated with the design and construction of super-tall buildings, has attracted the attention of designers for use in enhancing the control effectiveness in mega-frame buildings. In this paper, a dynamic equation and method to assemble parameter matrixes for a mega-sub controlled structure under random wind loads is presented. Semi-active control using magnetorheological dampers for the MSCS under random wind loads is investigated, and is compared with a corresponding system without dampers. A parametric study of the relative stiffness ratio and relative mass ratio between the mega-frame and the substructures, as well as the additional column stiffness ratio that influences the response control effectiveness of the MSCS, is discussed. The studies reveal, for the first time, that different control mechanisms exist. The results indicate that the proposed structure employing semi-active control can offer an effective control mechanism. Guidelines for selecting parameters are provided based on the analytical study.
文摘In this paper, the control performance is investigated of Circular Tuned Liquid Column Dampers (CTLCD) over torsional response of offshore platform structures excited by ground motions. Based on the equation of motion for the CTLCD-structure system, the optimal control parameters of CTLCD are given through some derivations on the supposition that the ground motion is a stochastic process. The influence of systematic parameters on the equivalent damping ratio of the structures is analyzed with purely torsional vibration and translational-torsional coupled vibration, respectively. The results show that the Circular Tuned Liquid Column Damper (CTLCD) is an effective torsional response control device.
基金supported by the National Natural Science Foundation of China (10872096)the Open Fund of State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology (KFJJ09-13)
文摘An oblique detonation wave for a Mach 7 inlet flow over a long enough wedge of 30 turning angle is simulated numerically using Euler equation and one-step rection model.The fifth-order WENO scheme is adopted to capture the shock wave.The numerical results show that with the compression of the wedge wall the detonation wave front structure is divided into three sections：the ZND model-like strcuture,single-sided triple point structure and dual-headed triple point strucuture.The first structure is the smooth straight,and the second has the characteristic of the triple points propagating dowanstream only with the same velocity,while the dual-headed triple point structure is very complicated.The detonation waves facing upstream and downstream propagate with different velocities,in which the periodic collisions of the triple points cause the oscillation of the detonation wave front.This oscillation process has temporal and spatial periodicity.In addition,the triple point trace are recorded to obtain different cell structures in three sections.
基金A Project supported by the National Natural Science Foundation of China (Nos.9487001,49173131)
文摘The continental margin of Northeast China and its adjacent areas is composed of two tectonic belts. The inner belt is a collage made up of fragments resulting from breakup of an old land with the north part related to the evolution of the Palaeo-Asian Ocean and the south part to the evolution of the Palaeo - Pacific Ocean. The outer belt is a Mesozoic terrane, which is a melange made up of fragments of the Late Palaeozoic to Early Mesozoic oceanic crust and the Late M esozoic trench accumulations.There existed another ocean-the Palaeo - Pacific Ocean during the period from the closing of the Palaeo-Asian Ocean to the opening of the modern Pacific Ocean or from the Devonian to Jurassic, and the ocean-floor spreading of the Palaeo - Pacific Ocean led to the formation of the above-mentioned tectonic belts. The development of the strike-slip fault system after the Late Jurassic and the formation of an epicontinental volcano -plutonic rock belt in the Late Cretaceous to Early Tertiary are attributed to the interaction between the modern Pacific plate and the Eurasian plate.
