The present work aims to assess earthquake-induced earth-retaining(ER)wall displacement.This study is on the dynamics analysis of various earth-retaining wall designs in hollow precast concrete panels,reinforcement co...The present work aims to assess earthquake-induced earth-retaining(ER)wall displacement.This study is on the dynamics analysis of various earth-retaining wall designs in hollow precast concrete panels,reinforcement concrete facing panels,and gravity-type earth-retaining walls.The finite element(FE)simulations utilized a 3D plane strain condition to model full-scale ER walls and numerous nonlinear dynamics analyses.The seismic performance of differentmodels,which includes reinforcement concrete panels and gravity-type and hollowprecast concrete ER walls,was simulated and examined using the FE approach.It also displays comparative studies such as stress distribution,deflection of the wall,acceleration across the wall height,lateral wall displacement,lateral wall pressure,and backfill plastic strain.Three components of the created ER walls were found throughout this research procedure.One is a granular reinforcement backfill,while the other is a wall-facing panel and base foundation.The dynamic response effects of varied earth-retaining walls have also been studied.It was discovered that the facing panel of the model significantly impacts the earthquake-induced displacement of ER walls.The proposed analytical model’s validity has been evaluated and compared with the reinforcement concrete facing panels,gravity-type ER wall,scientifically available data,and American Association of State Highway and Transportation Officials(AASHTO)guidelines results based on FE simulation.The results of the observations indicate that the hollow prefabricated concrete ER wall is the most feasible option due to its lower displacement and high-stress distribution compared to the two types.The methodology and results of this study establish standards for future analogous investigations and professionals,particularly in light of the increasing computational capabilities of desktop computers.展开更多
The impact sensitivity assessment of spacecraft is to obtain the probability of spacecraft encountering the OD/M(orbital debris or meteoroid),which is a prerequisite for survivability assessment of on-orbit spacecraft...The impact sensitivity assessment of spacecraft is to obtain the probability of spacecraft encountering the OD/M(orbital debris or meteoroid),which is a prerequisite for survivability assessment of on-orbit spacecraft.An impact sensitivity assessment method of spacecraft based on virtual exterior wall was proposed to improve the computational efficiency.This method eliminates determination of the outermost surface elements of the spacecraft before generating the debris rays,which are assumed to originate from a non-concave virtual wall that completely wraps the spacecraft.The Dist Mesh method was adopted for the generating of the virtual wall to ensure its mesh quality.The influences of the sizes,mesh densities,shapes of the virtual wall on the efficiency and accuracy were considered to obtain the best combination of the size and mesh density of the wall and spacecraft.The results of this method were compared with those of S3DE(Survivability of Spacecraft in Space Debris Environment),BUMPER,MDPANTO,ESABASE2/Debris to verify the feasibility of the method.The PCHIP(Piecewise Cubic Hermite Interpolating Polynomial)was used to fit the size vs.flux relationship of the space debris to acquire the impact probability of OD/M with arbitrary size on the spacecraft.展开更多
If βN exceeds βNno-wall, the plasma will be unstable because of external kink and resistive wall mode (RWM). In this article, the effect of the passive structure and the toroidal rotation on the RWM stability in t...If βN exceeds βNno-wall, the plasma will be unstable because of external kink and resistive wall mode (RWM). In this article, the effect of the passive structure and the toroidal rotation on the RWM stability in the experimental advanced superconducting tokamak (EAST) are simulated with CHEASE and MARS codes. A model using a one-dimensional (1D) surface to present the effect of the passive plate is proved to be credible. The no wall fiN limit is about 3li, and the ideal wall βN limit is about 4.5li on EAST. It is found that the rotation near the q = 2 surface and the plasma edge affects the RWM more.展开更多
One new coordination polymer with the chemical formula [CoCu2L2·K2·1.5C2H5OH]n(H4L = 2-hydroxy-3-[(E)-({3-[(2-hydroxybenzoyl)amino]propyl}imino)methyl] benzoic acid) has been synthesized based on the...One new coordination polymer with the chemical formula [CoCu2L2·K2·1.5C2H5OH]n(H4L = 2-hydroxy-3-[(E)-({3-[(2-hydroxybenzoyl)amino]propyl}imino)methyl] benzoic acid) has been synthesized based on the slow diffusion method,and characterized by IR spectroscopy,thermalgravimetric and X-ray diffraction analysis.It crystallizes in the monoclinic system,space group P21/n with a = 11.98860(10),b = 24.4279(3),c = 14.9008(2) ,β = 104.7490(10)°,V = 4220.01(8) 3,Z = 2,Mr = 1009.94,Dc = 1.590 g/cm3,F(000) = 2056,μ(MoKα) = 1.649 mm-1,the final R = 0.0411 and wR = 0.1178 for 5920 observed reflections with I 2σ(I).The compound possesses a 2D brick wall structure constructed from trinuclear units.展开更多
The energy efficiency design of the exterior wall in the buildings of the hot summer and cold winter zone of China should consider the heat prevention in summer and the heat insulation in winter. The self-insulation o...The energy efficiency design of the exterior wall in the buildings of the hot summer and cold winter zone of China should consider the heat prevention in summer and the heat insulation in winter. The self-insulation of the exterior?wall is a more feasible design to satisfy the energy efficiency of buildings in the?zone. However, the systematic research is urgently needed for the self-insulation of the exterior wall in the hot summer and cold winter zone of China. The paper tested the thermal performance of the common non-clay materials such as shale sintered hollow brick, sand autoclaved aerated concrete block, etc. by means of indoor experiments. The energy efficiency effect of the common materials was verified using dynamic calculation soft PKPM and several constitutions of exterior wall with different main bricks and insulation materials on the heat bridge were simulated, too. Besides, the tests of the thermal performance of exterior wall in real constructions were carried out to testify the practical effect of the recommended constitutions of exterior wall with different main bricks and insulation materials on the heat bridge. The conclusions are: the physical and thermal properties of the six non-clay wall material are better than the clay porous brick;the thermal performance of the non-clay brick can be improved obviously through the rational arrangement of the holes;shale sintered hollow brick after increasing the holes and rationalizing the hole arrangement and sand autoclaved aerated concrete block are recommended for buildings in the hot summer and cold winter area of China. The dynamic calculation results show that the thermal performances?of the non-clay materials are all satisfied with the energy efficiency;The heat transfer coefficient of the exterior wall with composition?③,?in which?the main wall was sand autoclaved aerated concrete block and the material on the heat bridge was sand autoclaved aerated concrete plate, is the smallest among the three recommended compositions.展开更多
Pile foundation bearing-retaining wall combination structure is a new type of support structure developed in recent years.This article focuses on the characteristics,advantages,and application scope of the support str...Pile foundation bearing-retaining wall combination structure is a new type of support structure developed in recent years.This article focuses on the characteristics,advantages,and application scope of the support structure,while combining a variety of algorithms,according to different geological conditions and slope stability,as well as summarizes the pile foundation bearing-retaining wall combination structure force analysis and design methods,taking a high-fill road project in Chongqing as an example.The application of this support structure under special conditions,such as thicker soil layer,steeper sliding surface,weak foundation,and limited slope release conditions,is presented,which illustrates the technical advantages of this support structure and proving that it has several other advantages,including clear force mechanism as well as economic and reasonable structure,thus providing reference for similar projects.展开更多
This study focuses on non-linear seismic response of concrete gravity quay-wall structures subjected to near-fault ground motions, a subject which seems not to have received much attention in the literature. A two-dim...This study focuses on non-linear seismic response of concrete gravity quay-wall structures subjected to near-fault ground motions, a subject which seems not to have received much attention in the literature. A two-dimensional coupled fluid-structure-soil finite element modelling is employed to obtain the quay-wall response. The seawater medium is represented by acoustic type, potential based fluid elements. The elasto-plastic behavior of the soil medium is idealized using Drucker-Prager yield criterion based on associated flow rule assumption. Four nodded plane strain elements are used to model the concrete wall, foundation, subsoil, backfill and seabed zones. Fluid Structure Interface (FSI) elements are considered between the seawater interfaces with the quay-wall and the seabed. Frictional contact elements are employed between the wall and soil interfaces. The numerical model is validated using field measurements available for permanent drifts in a quay-wall damaged during Kobe earthquake. Reasonable agreements are obtained between the model predictions and the field measurements. Non-linear seismic analyses of the selected quay-wall subjected to both near-fault and far-fault ground motions are performed. An incremental dynamic analysis approach (IDA) is used. In general, at least for models examined in the current study, the gravity quay-walls are found to be more vulnerable to near-field, in comparison with the corresponding far-field, earthquakes.展开更多
In this study, the relationship between skin structure and shear strength distribution of thin-wall injection molded polypropylene (PP) molded at different molecular weight and molecular distribution was investigated....In this study, the relationship between skin structure and shear strength distribution of thin-wall injection molded polypropylene (PP) molded at different molecular weight and molecular distribution was investigated. Skin-core structure, cross-sectional morphology, crystallinity, crystal orientation, crystal morphology and molecular orientation were evaluated by using polarized optical microscope, differential scanning calorimeter, X-ray spectroscopic analyzer and laser Raman spectroscopy, respectively, while the shear strength distribution was investigated using a micro cutting method called SAICAS (Surface And Interfacial Cutting Analysis System). The results indicated that the difference of molecular weight and molecular weight distribution showed own skin layer thickness. Especially, high molecular weight sample showed thicker layer of the lamellar orientation and molecular orientation than low molecular weight sample. In addition, wide molecular distribution sample showed large crystal orientation layer.展开更多
Efficient methods for incorporating engineering experience into the intelligent generation and optimization of shear wall structures are lacking,hindering intelligent design performance assessment and enhancement.This...Efficient methods for incorporating engineering experience into the intelligent generation and optimization of shear wall structures are lacking,hindering intelligent design performance assessment and enhancement.This study introduces an assessment method used in the intelligent design and optimization of shear wall structures that effectively combines mechanical analysis and formulaic encoding of empirical rules.First,the critical information about the structure was extracted through data structuring.Second,an empirical rule assessment method was developed based on the engineer's experience and design standards to complete a preliminary assessment and screening of the structure.Subsequently,an assessment method based on mechanical performance and material consumption was used to compare different structural schemes comprehensively.Finally,the assessment effectiveness was demonstrated using a typical case.Compared to traditional assessment methods,the proposed method is more comprehensive and significantly more efficient,promoting the intelligent transformation of structural design.展开更多
A three-dimensional nonlinear modeling strategy for simulating the seismic response of slender reinforced concrete structural walls with different cross-sectional shapes is presented in this paper.A combination of non...A three-dimensional nonlinear modeling strategy for simulating the seismic response of slender reinforced concrete structural walls with different cross-sectional shapes is presented in this paper.A combination of nonlinear multi-layer shell elements and displacement-based beam-column elements are used to model the unconfined and confined parts of the walls,respectively.A uniaxial material model for reinforcing steel bars that includes buckling and low-cyclic fatigue effects is used to model the longitudinal steel bars within the structural walls.The material model parameters related to the buckling length are defined based on an analytical expression for reinforcing steel bars embedded in reinforced concrete elements,which are developed based on beam-on-springs model,and validated with experimental tests of boundary elements of structural walls available in the literature.Six experimental case studies of reinforced concrete walls with rectangularshape,T-shape,and U-shape cross-section are used to validate the structural wall numerical modeling strategy.展开更多
The aim of this study is to analyze of the cable-glass systems which are used on the glass curtain wall according to their types, degree, architectural and structural effects. The suspended glass system with pre-stres...The aim of this study is to analyze of the cable-glass systems which are used on the glass curtain wall according to their types, degree, architectural and structural effects. The suspended glass system with pre-stressed cable truss (SGSPCT) is widely started to apply after the 1980’s with Serres building. The advantages of these systems are to provide the transparency on the fa?ades and speedy construction process with minimum materials. The disadvantages are: more expensive than other systems and so many details for the joints and load distribution calculations. There are three different architectural design typologies of the SGSPCT system. These are distance bridging systems, between floor system and independent body. These three different typologies can be seen on the same building at the same time. This system has been known as complex structure systems. The twenty five glass buildings which are designed in different systems have been analyzed during this study. After these analyses the five glass buildings which are designed with cable-truss system have been selected for scope of the study. These selected buildings have been included of three different cable-truss system typologies and degree. The methodology of this study is literature survey and building analyses method. The written and visual documents involve books, theses, reports, articles, magazines, drawings, internet sources and applied connection details of the glass buildings. The selected five glass buildings have been detailed analyzed with their architectural drawings, photographs and details. The study consists of five chapters including the introduction chapter. The general information of the glass building and cable-glass system has been mentioned in the first chapter. The structural features, details and analytical information on systems have been explained of the selected buildings in the second chapter. The detailed analyses of these selected buildings have been done according to their schematic drawings with the plans, sections and load distribution in the third chapter. The fourth chapter is discussion section. In this section, cable-truss systems have been compared with their advantages and disadvantages to the other systems. The fifth chapter is the last chapter, many advantages of cable-truss systems have been concluded that the use of glass substrates.展开更多
A new type of ductile lowrise shearwall with many short horizontalkeyways is proposed in this paper in order to improve the earthquake resistant behav-ior of ordinary lowrise shearwall.The behavior of this wall is stu...A new type of ductile lowrise shearwall with many short horizontalkeyways is proposed in this paper in order to improve the earthquake resistant behav-ior of ordinary lowrise shearwall.The behavior of this wall is studied through low-frequency cyclic loading test.Based on the test results,the paper puts forward thedifferent restoring force models for different lowrise shearwalls,and a program fortheir nonlinear dynamic analysis is worked out.Thr(?)h directly inputting earth-quake waves,the paper analyses the dynamic response and energy dissipation of 3types of lowrise shearwalls.The calculation results dem(?)strate that the newly de-vised ductile shearwall has good earthquake resistant behavior.展开更多
In slab column-shear wall structures,both the whole structure′s seismic behavior and failure mode are greatly influenced by the distribution of horizontal seismic forces between slab-column and shear wall.In this pap...In slab column-shear wall structures,both the whole structure′s seismic behavior and failure mode are greatly influenced by the distribution of horizontal seismic forces between slab-column and shear wall.In this paper,a pushover analysis of topical slab column-shear wall structure was carried out,the seismic shear force that the slab-column and shear wall should undertake was worked out,the influences of plastic internal force redistribution and structure stiffness characteristic value on horizontal seismic distribution were studied and the calculation formula was given.The analysis results showed that with the yield of the shear walls,the story shear force was undertaken by slab-columns correspondingly increased while with the decrease of characteristic value of stiffness of a structure,and the horizontal seismic force was undertaken by slab-columns correspondingly decreased.According to the code,the design of horizontal force distribution may be cause insecurity problems,so it is necessary to give the distribution law of horizontal seismic forces in slab-column shear wall structures as the supplement to the corresponding regulation of the Code.展开更多
The Indian test blanket module(TBM) program in ITER is one of the major steps in the Indian fusion reactor program for carrying out the R&D activities in the critical areas like design of tritium breeding blankets ...The Indian test blanket module(TBM) program in ITER is one of the major steps in the Indian fusion reactor program for carrying out the R&D activities in the critical areas like design of tritium breeding blankets relevant to future Indian fusion devices(ITER relevant and DEMO).The Indian Lead–Lithium Cooled Ceramic Breeder(LLCB) blanket concept is one of the Indian DEMO relevant TBM,to be tested in ITER as a part of the TBM program.Helium-Cooled Ceramic Breeder(HCCB) is an alternative blanket concept that consists of lithium titanate(Li_2TiO_3) as ceramic breeder(CB) material in the form of packed pebble beds and beryllium as the neutron multiplier.Specifically,attentions are given to the optimization of first wall coolant channel design and size of breeder unit module considering coolant pressure and thermal loads for the proposed Indian HCCB blanket based on ITER relevant TBM and loading conditions.These analyses will help proceeding further in designing blankets for loads relevant to the future fusion device.展开更多
Motivated by the seismic damage observed to reinforced concrete (RC) frame structures during the Wenchuan earthquake, the effect of infill walls on the seismic performance of a RC frame is studied in this paper. Inf...Motivated by the seismic damage observed to reinforced concrete (RC) frame structures during the Wenchuan earthquake, the effect of infill walls on the seismic performance of a RC frame is studied in this paper. Infill walls, especially those made of masonry, offer some amount of stiffness and strength. Therefore, the effect of infill walls should be considered during the design of RC frames. In this study, an analysis of the recorded ground motion in the Wenehuan earthquake is performed. Then, a numerical model is developed to simulate the infill walls. Finally, nonlinear dynamic analysis is carried out on a RC frame with and without infill walls, respectively, by using CANNY software. Through a comparative analysis, the following conclusions can be drawn. The failure mode of the frame with infill walls is in accordance with the seismic damage failure pattern, which is strong beam and weak column mode. This indicates that the infill walls change the failure pattern of the frame, and it is necessary to consider them in the seismic design of the RC frame. The numerical model presented in this paper can effectively simulate the effect of infill walls on the RC frame.展开更多
The primary energy demand increases, but a large amount of waste heat resources w</span><span style="font-family:Verdana;">ere </span><span style="font-family:Verdana;">...The primary energy demand increases, but a large amount of waste heat resources w</span><span style="font-family:Verdana;">ere </span><span style="font-family:Verdana;">not effectively used. To explore the influence of particle stacking structure on waste heat recovery process, CFD method was used to simulate. An unsteady heat transfer model of two particles was established, effect of particle stacking angle on heat transfer characteristics of the particles close to the wall under different initial temperature conditions was studied. Results show that: higher initial temperature, resulting in increased heat transfer time, the larger particle stacking angle causes the shortening of heat transfer time. When initial temperature is 1073</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">K, the average wall heat flux shows a trend of rapid decline first and then a slow one. At the same moment, the larger stacking angle causes smaller particle average temperature. The change of particle stacking angle shows a greater impact on the temperature of the particles close to adiabatic wall. The increase in the stacking angle resulting in better heat transfer characteristics between particles.展开更多
This paper proposes a novel application of cohomology to protein structure analysis. Since proteins interact each other by forming transient protein complexes, their shape (e.g., shape complementarity) plays an import...This paper proposes a novel application of cohomology to protein structure analysis. Since proteins interact each other by forming transient protein complexes, their shape (e.g., shape complementarity) plays an important role in their functions. In our mathematical toy models, proteins are represented as a loop of triangles (2D model) or tetrahedra (3D model), where their interactions are defined as fusion of loops. The purpose of this paper is to describe the conditions for loop fusion using the language of cohomology. In particular, this paper uses cohomology to describe the conditions for “allosteric regulation”, which has been attracted attention in safer drug discovery. I hope that this paper will provide a new perspective on the mechanism of allosteric regulation. Advantages of the model include its topological nature. That is, we can deform the shape of loops by deforming the shape of triangles (or tetrahedra) as long as their folded structures are preserved. Another advantage is the simplicity of the “allosteric regulation” mechanism of the model. Furthermore, the effect of the “post-translational modification” can be understood as a resolution of singularities of a flow of triangles (or tetrahedra). No prior knowledge of either protein science, exterior calculus, or cohomology theory is required. The author hopes that this paper will facilitate the interaction between mathematics and protein science.展开更多
According to the bearing structure, building materials and process, this paper adobe housing will be divided into Adobe bearing wall, brick wall, hybrid bearing housing and bearing timber frame house. Research shows t...According to the bearing structure, building materials and process, this paper adobe housing will be divided into Adobe bearing wall, brick wall, hybrid bearing housing and bearing timber frame house. Research shows that, different types of housing distribution has regional and age characteristics, seismic performance is different, but there are different seismic safety problems; in order to improve the seismic capacity of rural houses, we need to accelerate the implementation of rural residential earthquake safety project, speed up the reconstruction of the demolition reconstruction and seismic reinforcement work, to carry out research on seismic technology houses, promote rural seismic residential.展开更多
An experimental measurement was performed us- ing time-resolved particle image velocimetry (TRPIV) to in- vestigate the spatial topological character of coherent struc- tures in wall-bounded turbulence of polymer ad...An experimental measurement was performed us- ing time-resolved particle image velocimetry (TRPIV) to in- vestigate the spatial topological character of coherent struc- tures in wall-bounded turbulence of polymer additive solu- tion. The fully developed near-wall turbulent flow fields with and without polymer additives at the same Reynolds number were measured by TRPIV in a water channel. The compar- isons of turbulent statistics confirm that due to viscoelastic structure of long-chain polymers, the wall-normal velocity fluctuation and Reynolds shear stress in the near-wall region are suppressed significantly. Furthermore, it is noted that such a behavior of polymers is closely related to the decease of the motion of the second and forth quadrants, i.e., the ejection and sweep events, in the near-wall region. The spa- tial topological mode of coherent structures during bursts has been extracted by the new mu-level criteria based on locally averaged velocity structure function. Although the general shapes of coherent structures are unchanged by polymer additives, the fluctuating velocity, velocity gradient, velocity strain rate and vorticity of coherent structures during burst events are suppressed in the polymer additive solution com- pared with that in water. The results show that due to the polymer additives the occurrence and intensity of coherent structures are suppressed, leading to drag reduction.展开更多
基金supported by Supported by the Science and Technology Research Program of the Institute of Mountain Hazards and Environment,CAS(IMHE-ZDRW-01)the National Natural Science Foundation of China,China(Grant Numbers:42077275&42271086)the Special Project of Basic Research-Key Project,Yunnan(Grant Number:202301AS070039).
文摘The present work aims to assess earthquake-induced earth-retaining(ER)wall displacement.This study is on the dynamics analysis of various earth-retaining wall designs in hollow precast concrete panels,reinforcement concrete facing panels,and gravity-type earth-retaining walls.The finite element(FE)simulations utilized a 3D plane strain condition to model full-scale ER walls and numerous nonlinear dynamics analyses.The seismic performance of differentmodels,which includes reinforcement concrete panels and gravity-type and hollowprecast concrete ER walls,was simulated and examined using the FE approach.It also displays comparative studies such as stress distribution,deflection of the wall,acceleration across the wall height,lateral wall displacement,lateral wall pressure,and backfill plastic strain.Three components of the created ER walls were found throughout this research procedure.One is a granular reinforcement backfill,while the other is a wall-facing panel and base foundation.The dynamic response effects of varied earth-retaining walls have also been studied.It was discovered that the facing panel of the model significantly impacts the earthquake-induced displacement of ER walls.The proposed analytical model’s validity has been evaluated and compared with the reinforcement concrete facing panels,gravity-type ER wall,scientifically available data,and American Association of State Highway and Transportation Officials(AASHTO)guidelines results based on FE simulation.The results of the observations indicate that the hollow prefabricated concrete ER wall is the most feasible option due to its lower displacement and high-stress distribution compared to the two types.The methodology and results of this study establish standards for future analogous investigations and professionals,particularly in light of the increasing computational capabilities of desktop computers.
文摘The impact sensitivity assessment of spacecraft is to obtain the probability of spacecraft encountering the OD/M(orbital debris or meteoroid),which is a prerequisite for survivability assessment of on-orbit spacecraft.An impact sensitivity assessment method of spacecraft based on virtual exterior wall was proposed to improve the computational efficiency.This method eliminates determination of the outermost surface elements of the spacecraft before generating the debris rays,which are assumed to originate from a non-concave virtual wall that completely wraps the spacecraft.The Dist Mesh method was adopted for the generating of the virtual wall to ensure its mesh quality.The influences of the sizes,mesh densities,shapes of the virtual wall on the efficiency and accuracy were considered to obtain the best combination of the size and mesh density of the wall and spacecraft.The results of this method were compared with those of S3DE(Survivability of Spacecraft in Space Debris Environment),BUMPER,MDPANTO,ESABASE2/Debris to verify the feasibility of the method.The PCHIP(Piecewise Cubic Hermite Interpolating Polynomial)was used to fit the size vs.flux relationship of the space debris to acquire the impact probability of OD/M with arbitrary size on the spacecraft.
基金supported by the National Magnetic Confinement Fusion Science Program of China(Grant Nos.2012GB105000,2011GB101000,2011GB107000,and 2013013GB102000)the National Natural Science Foundation of China(Grant Nos.10725523,10721505,10090212,111005037,and 11205199)
文摘If βN exceeds βNno-wall, the plasma will be unstable because of external kink and resistive wall mode (RWM). In this article, the effect of the passive structure and the toroidal rotation on the RWM stability in the experimental advanced superconducting tokamak (EAST) are simulated with CHEASE and MARS codes. A model using a one-dimensional (1D) surface to present the effect of the passive plate is proved to be credible. The no wall fiN limit is about 3li, and the ideal wall βN limit is about 4.5li on EAST. It is found that the rotation near the q = 2 surface and the plasma edge affects the RWM more.
基金Supported by the Technology Chamber of Henan Province (092300410031)the Education Chamber of Henan Province (2009A150005)
文摘One new coordination polymer with the chemical formula [CoCu2L2·K2·1.5C2H5OH]n(H4L = 2-hydroxy-3-[(E)-({3-[(2-hydroxybenzoyl)amino]propyl}imino)methyl] benzoic acid) has been synthesized based on the slow diffusion method,and characterized by IR spectroscopy,thermalgravimetric and X-ray diffraction analysis.It crystallizes in the monoclinic system,space group P21/n with a = 11.98860(10),b = 24.4279(3),c = 14.9008(2) ,β = 104.7490(10)°,V = 4220.01(8) 3,Z = 2,Mr = 1009.94,Dc = 1.590 g/cm3,F(000) = 2056,μ(MoKα) = 1.649 mm-1,the final R = 0.0411 and wR = 0.1178 for 5920 observed reflections with I 2σ(I).The compound possesses a 2D brick wall structure constructed from trinuclear units.
文摘The energy efficiency design of the exterior wall in the buildings of the hot summer and cold winter zone of China should consider the heat prevention in summer and the heat insulation in winter. The self-insulation of the exterior?wall is a more feasible design to satisfy the energy efficiency of buildings in the?zone. However, the systematic research is urgently needed for the self-insulation of the exterior wall in the hot summer and cold winter zone of China. The paper tested the thermal performance of the common non-clay materials such as shale sintered hollow brick, sand autoclaved aerated concrete block, etc. by means of indoor experiments. The energy efficiency effect of the common materials was verified using dynamic calculation soft PKPM and several constitutions of exterior wall with different main bricks and insulation materials on the heat bridge were simulated, too. Besides, the tests of the thermal performance of exterior wall in real constructions were carried out to testify the practical effect of the recommended constitutions of exterior wall with different main bricks and insulation materials on the heat bridge. The conclusions are: the physical and thermal properties of the six non-clay wall material are better than the clay porous brick;the thermal performance of the non-clay brick can be improved obviously through the rational arrangement of the holes;shale sintered hollow brick after increasing the holes and rationalizing the hole arrangement and sand autoclaved aerated concrete block are recommended for buildings in the hot summer and cold winter area of China. The dynamic calculation results show that the thermal performances?of the non-clay materials are all satisfied with the energy efficiency;The heat transfer coefficient of the exterior wall with composition?③,?in which?the main wall was sand autoclaved aerated concrete block and the material on the heat bridge was sand autoclaved aerated concrete plate, is the smallest among the three recommended compositions.
基金Youth Project of Science and Technology Research of Chongqing Municipal Education Commission“Research on the Promotion of Pile Foundation Bearing-Retaining Wall Combined Structure Technology”(Project Number:KJQN201905601)Youth Project of Science and Technology Research of Chongqing Education Commission“Research on Construction Monitoring and Risk Warning of Deep Foundation Pit Project Based on BIM+Internet of Things”(Project Number:KJQN201904306)。
文摘Pile foundation bearing-retaining wall combination structure is a new type of support structure developed in recent years.This article focuses on the characteristics,advantages,and application scope of the support structure,while combining a variety of algorithms,according to different geological conditions and slope stability,as well as summarizes the pile foundation bearing-retaining wall combination structure force analysis and design methods,taking a high-fill road project in Chongqing as an example.The application of this support structure under special conditions,such as thicker soil layer,steeper sliding surface,weak foundation,and limited slope release conditions,is presented,which illustrates the technical advantages of this support structure and proving that it has several other advantages,including clear force mechanism as well as economic and reasonable structure,thus providing reference for similar projects.
文摘This study focuses on non-linear seismic response of concrete gravity quay-wall structures subjected to near-fault ground motions, a subject which seems not to have received much attention in the literature. A two-dimensional coupled fluid-structure-soil finite element modelling is employed to obtain the quay-wall response. The seawater medium is represented by acoustic type, potential based fluid elements. The elasto-plastic behavior of the soil medium is idealized using Drucker-Prager yield criterion based on associated flow rule assumption. Four nodded plane strain elements are used to model the concrete wall, foundation, subsoil, backfill and seabed zones. Fluid Structure Interface (FSI) elements are considered between the seawater interfaces with the quay-wall and the seabed. Frictional contact elements are employed between the wall and soil interfaces. The numerical model is validated using field measurements available for permanent drifts in a quay-wall damaged during Kobe earthquake. Reasonable agreements are obtained between the model predictions and the field measurements. Non-linear seismic analyses of the selected quay-wall subjected to both near-fault and far-fault ground motions are performed. An incremental dynamic analysis approach (IDA) is used. In general, at least for models examined in the current study, the gravity quay-walls are found to be more vulnerable to near-field, in comparison with the corresponding far-field, earthquakes.
文摘In this study, the relationship between skin structure and shear strength distribution of thin-wall injection molded polypropylene (PP) molded at different molecular weight and molecular distribution was investigated. Skin-core structure, cross-sectional morphology, crystallinity, crystal orientation, crystal morphology and molecular orientation were evaluated by using polarized optical microscope, differential scanning calorimeter, X-ray spectroscopic analyzer and laser Raman spectroscopy, respectively, while the shear strength distribution was investigated using a micro cutting method called SAICAS (Surface And Interfacial Cutting Analysis System). The results indicated that the difference of molecular weight and molecular weight distribution showed own skin layer thickness. Especially, high molecular weight sample showed thicker layer of the lamellar orientation and molecular orientation than low molecular weight sample. In addition, wide molecular distribution sample showed large crystal orientation layer.
文摘Efficient methods for incorporating engineering experience into the intelligent generation and optimization of shear wall structures are lacking,hindering intelligent design performance assessment and enhancement.This study introduces an assessment method used in the intelligent design and optimization of shear wall structures that effectively combines mechanical analysis and formulaic encoding of empirical rules.First,the critical information about the structure was extracted through data structuring.Second,an empirical rule assessment method was developed based on the engineer's experience and design standards to complete a preliminary assessment and screening of the structure.Subsequently,an assessment method based on mechanical performance and material consumption was used to compare different structural schemes comprehensively.Finally,the assessment effectiveness was demonstrated using a typical case.Compared to traditional assessment methods,the proposed method is more comprehensive and significantly more efficient,promoting the intelligent transformation of structural design.
文摘A three-dimensional nonlinear modeling strategy for simulating the seismic response of slender reinforced concrete structural walls with different cross-sectional shapes is presented in this paper.A combination of nonlinear multi-layer shell elements and displacement-based beam-column elements are used to model the unconfined and confined parts of the walls,respectively.A uniaxial material model for reinforcing steel bars that includes buckling and low-cyclic fatigue effects is used to model the longitudinal steel bars within the structural walls.The material model parameters related to the buckling length are defined based on an analytical expression for reinforcing steel bars embedded in reinforced concrete elements,which are developed based on beam-on-springs model,and validated with experimental tests of boundary elements of structural walls available in the literature.Six experimental case studies of reinforced concrete walls with rectangularshape,T-shape,and U-shape cross-section are used to validate the structural wall numerical modeling strategy.
文摘The aim of this study is to analyze of the cable-glass systems which are used on the glass curtain wall according to their types, degree, architectural and structural effects. The suspended glass system with pre-stressed cable truss (SGSPCT) is widely started to apply after the 1980’s with Serres building. The advantages of these systems are to provide the transparency on the fa?ades and speedy construction process with minimum materials. The disadvantages are: more expensive than other systems and so many details for the joints and load distribution calculations. There are three different architectural design typologies of the SGSPCT system. These are distance bridging systems, between floor system and independent body. These three different typologies can be seen on the same building at the same time. This system has been known as complex structure systems. The twenty five glass buildings which are designed in different systems have been analyzed during this study. After these analyses the five glass buildings which are designed with cable-truss system have been selected for scope of the study. These selected buildings have been included of three different cable-truss system typologies and degree. The methodology of this study is literature survey and building analyses method. The written and visual documents involve books, theses, reports, articles, magazines, drawings, internet sources and applied connection details of the glass buildings. The selected five glass buildings have been detailed analyzed with their architectural drawings, photographs and details. The study consists of five chapters including the introduction chapter. The general information of the glass building and cable-glass system has been mentioned in the first chapter. The structural features, details and analytical information on systems have been explained of the selected buildings in the second chapter. The detailed analyses of these selected buildings have been done according to their schematic drawings with the plans, sections and load distribution in the third chapter. The fourth chapter is discussion section. In this section, cable-truss systems have been compared with their advantages and disadvantages to the other systems. The fifth chapter is the last chapter, many advantages of cable-truss systems have been concluded that the use of glass substrates.
文摘A new type of ductile lowrise shearwall with many short horizontalkeyways is proposed in this paper in order to improve the earthquake resistant behav-ior of ordinary lowrise shearwall.The behavior of this wall is studied through low-frequency cyclic loading test.Based on the test results,the paper puts forward thedifferent restoring force models for different lowrise shearwalls,and a program fortheir nonlinear dynamic analysis is worked out.Thr(?)h directly inputting earth-quake waves,the paper analyses the dynamic response and energy dissipation of 3types of lowrise shearwalls.The calculation results dem(?)strate that the newly de-vised ductile shearwall has good earthquake resistant behavior.
文摘In slab column-shear wall structures,both the whole structure′s seismic behavior and failure mode are greatly influenced by the distribution of horizontal seismic forces between slab-column and shear wall.In this paper,a pushover analysis of topical slab column-shear wall structure was carried out,the seismic shear force that the slab-column and shear wall should undertake was worked out,the influences of plastic internal force redistribution and structure stiffness characteristic value on horizontal seismic distribution were studied and the calculation formula was given.The analysis results showed that with the yield of the shear walls,the story shear force was undertaken by slab-columns correspondingly increased while with the decrease of characteristic value of stiffness of a structure,and the horizontal seismic force was undertaken by slab-columns correspondingly decreased.According to the code,the design of horizontal force distribution may be cause insecurity problems,so it is necessary to give the distribution law of horizontal seismic forces in slab-column shear wall structures as the supplement to the corresponding regulation of the Code.
文摘The Indian test blanket module(TBM) program in ITER is one of the major steps in the Indian fusion reactor program for carrying out the R&D activities in the critical areas like design of tritium breeding blankets relevant to future Indian fusion devices(ITER relevant and DEMO).The Indian Lead–Lithium Cooled Ceramic Breeder(LLCB) blanket concept is one of the Indian DEMO relevant TBM,to be tested in ITER as a part of the TBM program.Helium-Cooled Ceramic Breeder(HCCB) is an alternative blanket concept that consists of lithium titanate(Li_2TiO_3) as ceramic breeder(CB) material in the form of packed pebble beds and beryllium as the neutron multiplier.Specifically,attentions are given to the optimization of first wall coolant channel design and size of breeder unit module considering coolant pressure and thermal loads for the proposed Indian HCCB blanket based on ITER relevant TBM and loading conditions.These analyses will help proceeding further in designing blankets for loads relevant to the future fusion device.
基金the partial financial support from Kwang-Hua Fund for College of Civil Engineering,Tongji Universitythe National Natural Science Foundation of China(Grant No.51078274,51021140006)
文摘Motivated by the seismic damage observed to reinforced concrete (RC) frame structures during the Wenchuan earthquake, the effect of infill walls on the seismic performance of a RC frame is studied in this paper. Infill walls, especially those made of masonry, offer some amount of stiffness and strength. Therefore, the effect of infill walls should be considered during the design of RC frames. In this study, an analysis of the recorded ground motion in the Wenehuan earthquake is performed. Then, a numerical model is developed to simulate the infill walls. Finally, nonlinear dynamic analysis is carried out on a RC frame with and without infill walls, respectively, by using CANNY software. Through a comparative analysis, the following conclusions can be drawn. The failure mode of the frame with infill walls is in accordance with the seismic damage failure pattern, which is strong beam and weak column mode. This indicates that the infill walls change the failure pattern of the frame, and it is necessary to consider them in the seismic design of the RC frame. The numerical model presented in this paper can effectively simulate the effect of infill walls on the RC frame.
文摘The primary energy demand increases, but a large amount of waste heat resources w</span><span style="font-family:Verdana;">ere </span><span style="font-family:Verdana;">not effectively used. To explore the influence of particle stacking structure on waste heat recovery process, CFD method was used to simulate. An unsteady heat transfer model of two particles was established, effect of particle stacking angle on heat transfer characteristics of the particles close to the wall under different initial temperature conditions was studied. Results show that: higher initial temperature, resulting in increased heat transfer time, the larger particle stacking angle causes the shortening of heat transfer time. When initial temperature is 1073</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">K, the average wall heat flux shows a trend of rapid decline first and then a slow one. At the same moment, the larger stacking angle causes smaller particle average temperature. The change of particle stacking angle shows a greater impact on the temperature of the particles close to adiabatic wall. The increase in the stacking angle resulting in better heat transfer characteristics between particles.
文摘This paper proposes a novel application of cohomology to protein structure analysis. Since proteins interact each other by forming transient protein complexes, their shape (e.g., shape complementarity) plays an important role in their functions. In our mathematical toy models, proteins are represented as a loop of triangles (2D model) or tetrahedra (3D model), where their interactions are defined as fusion of loops. The purpose of this paper is to describe the conditions for loop fusion using the language of cohomology. In particular, this paper uses cohomology to describe the conditions for “allosteric regulation”, which has been attracted attention in safer drug discovery. I hope that this paper will provide a new perspective on the mechanism of allosteric regulation. Advantages of the model include its topological nature. That is, we can deform the shape of loops by deforming the shape of triangles (or tetrahedra) as long as their folded structures are preserved. Another advantage is the simplicity of the “allosteric regulation” mechanism of the model. Furthermore, the effect of the “post-translational modification” can be understood as a resolution of singularities of a flow of triangles (or tetrahedra). No prior knowledge of either protein science, exterior calculus, or cohomology theory is required. The author hopes that this paper will facilitate the interaction between mathematics and protein science.
文摘According to the bearing structure, building materials and process, this paper adobe housing will be divided into Adobe bearing wall, brick wall, hybrid bearing housing and bearing timber frame house. Research shows that, different types of housing distribution has regional and age characteristics, seismic performance is different, but there are different seismic safety problems; in order to improve the seismic capacity of rural houses, we need to accelerate the implementation of rural residential earthquake safety project, speed up the reconstruction of the demolition reconstruction and seismic reinforcement work, to carry out research on seismic technology houses, promote rural seismic residential.
基金supported by the National Natural Science Foundation of China(11272233)National Key Basic Research and Development Program(2012CB720101)2012 opening subjects of The State Key Laboratory of Nonlinear Mechanics(LNM),Institute of Mechanics,Chinese Academy of Sciences
文摘An experimental measurement was performed us- ing time-resolved particle image velocimetry (TRPIV) to in- vestigate the spatial topological character of coherent struc- tures in wall-bounded turbulence of polymer additive solu- tion. The fully developed near-wall turbulent flow fields with and without polymer additives at the same Reynolds number were measured by TRPIV in a water channel. The compar- isons of turbulent statistics confirm that due to viscoelastic structure of long-chain polymers, the wall-normal velocity fluctuation and Reynolds shear stress in the near-wall region are suppressed significantly. Furthermore, it is noted that such a behavior of polymers is closely related to the decease of the motion of the second and forth quadrants, i.e., the ejection and sweep events, in the near-wall region. The spa- tial topological mode of coherent structures during bursts has been extracted by the new mu-level criteria based on locally averaged velocity structure function. Although the general shapes of coherent structures are unchanged by polymer additives, the fluctuating velocity, velocity gradient, velocity strain rate and vorticity of coherent structures during burst events are suppressed in the polymer additive solution com- pared with that in water. The results show that due to the polymer additives the occurrence and intensity of coherent structures are suppressed, leading to drag reduction.