There are many problems and deficiencies in traditional bank protection methods,which cause certain damage to the ecological environment of river channels.Recently,the issues of river management,improving bank protect...There are many problems and deficiencies in traditional bank protection methods,which cause certain damage to the ecological environment of river channels.Recently,the issues of river management,improving bank protection technology,formulating reasonable construction measures,and ensuring the smooth and efficient implementation of construction have been receiving increasing attention.展开更多
MXenes are a family of two-dimensional (2D) transition metal carbides, carbonitrides/nitrides with superior physical and chemical properties, which have attracted extensive attention since the discovery in 2011. The i...MXenes are a family of two-dimensional (2D) transition metal carbides, carbonitrides/nitrides with superior physical and chemical properties, which have attracted extensive attention since the discovery in 2011. The impressive electrochemical activity of MXene makes it one of the most potential electrode materials in rechargeable batteries and supercapacitors. However, single-component MXene electrodes are difficult to achieve high specific capacity, efficient ion/electron transport, and high stability compatibility in an electrochemical environment. Studies have shown that it is an effective method to introduce nanomaterials between MXene layers to construct heterostructures and to improve the electrochemical performance through the synergistic effect among the components in the heterostructures. The introduction of nanomaterials can effectively suppress the restacking of MXene nanosheets, shorten the diffusion path of ions and promote the electrolyte transport, which is beneficial to enhance the rate performance of MXene;moreover, the excellent mechanical flexibility of MXene can reduce the volume expansion of nanomaterials during charge/discharge, thereby effectively protecting the integrity of the electrode structure and improving the cycling stability. Therefore, in this review, combined with theoretical calculations, we summarize the recent advances of MXene heterostructures in terms of synthesis strategies and energy storage applications, including supercapacitors, metal-ions batteries (Li, Na, K, Mg, Zn, Al) and metal anode protection. Furthermore, potential challenges and application perspectives for MXene heterostructures are also outlined.展开更多
Pyramids,symbols of the Ancient Egyptian civilization,are visited by tourists and studied by researchers from all around the world.However,the techniques used by Ancient Egyptians to construct the pyramid,specifically...Pyramids,symbols of the Ancient Egyptian civilization,are visited by tourists and studied by researchers from all around the world.However,the techniques used by Ancient Egyptians to construct the pyramid,specifically,how such a tall structure could have been constructed from huge blocks of stone with the limited productive forces at the time,remains a mystery to the world.Though numerous theories,such as the use of ramps,levers,pulleys,fluid buoyancy,and cast-in-place concrete,have been proposed in academia,no consensus has been reached to date.Based on mechanical principles and the productive forces available at the time,the famous Pyramid of Khufu is used as a case study in this paper to propose a theory of pit-aided construction.The main steps include the digging of the pit,the transportation of stone blocks into the pit,the layer-by-layer construction,and the layer-by-layer filling of soil until the top of the pyramid is completed.The main idea of the pit-aided construction was to use the self-weight of the stone material to achieve the transportation of stone blocks by converting potential energy to kinetic energy,thereby avoiding the large amounts of work that must be done to elevate the huge blocks of stone.The proposed theory of pit-aided construction is consistent with the cultural custom of burial that is associated with tomb construction,namely laying the deceased to rest through burial,and is also consistent with the productive forces available in Ancient Egypt at the time.展开更多
The construction of municipal roads and bridges is an important foundation for the smooth traveling and transportation.However,if there a reduction in the subgrade and pavement part,the safety and the comfort of the d...The construction of municipal roads and bridges is an important foundation for the smooth traveling and transportation.However,if there a reduction in the subgrade and pavement part,the safety and the comfort of the driver will be seriously affected,therefore,reasonable measures should be taken on time to tackle the related issues.The significance of subgrade and pavement construction in the subsidence section,the key points of the construction,and the appropriate control measures that are should be taken in the actual construction,was discussed in this paper.Further,this paper analyzes the availability of the subgrade and pavement construction technology for the municipal roads and bridges,to provide a reference for engineers.展开更多
Building information modeling(BIM)technology simulates visual information data by integrating the information data of construction projects.The presentation of information parameters allows better collaborative manage...Building information modeling(BIM)technology simulates visual information data by integrating the information data of construction projects.The presentation of information parameters allows better collaborative management of the construction process.BIM technology is applied to integrate information data during the construction of prefabricated structures,analyze the source of information data of construction projects,and build a digital information model.BIM technology consists of information integration function,information data simulation,cross-region coordination and more.Therefore,this paper applies it to the process of prefabricated structure design,puts forward relevant technical research strategies,establishes relevant models,ensures the accuracy of drawing,and simulates the final construction effect according to the combination of arranged relevant parameters.展开更多
The aim of the study is to present a multi-leveled comparative evaluation approach for structural characteristics of historic masonry monuments so that the consciousness in their authentic designs is comprehended,and ...The aim of the study is to present a multi-leveled comparative evaluation approach for structural characteristics of historic masonry monuments so that the consciousness in their authentic designs is comprehended,and the optimum structural performance is clarified.A case study approach is preferred by the examination of the Bedesten(15th‒16th centuries)located in Bergama,_Izmir,Turkey.The structure is documented through tacheometric techniques.The construction techniques of structural elements are mapped.These documented qualities are compared with similar period and/or function structures in order to rank the frequency of construction details.The geometrical factor of safety state is defined theoretically for domes and arches.Finite element macro model of the Bedesten is generated in ANSYS software and overall structural analysis of the structure is made to evaluate the safety level of historic building by the limit states through self-weight analysis.The presented study shows that the rare structural characteristics can both contribute to structural safety and cause vulnerability.Therefore,total consciousness in structural design cannot be stated for the studied Bedesten,but the structural designs that are often preferred in the monuments built at the same period in the proximity to each other have low vulnerability,yielding to conscious preferences.展开更多
For more than a decade,a wide range of Spanish case studies,relating especially to rural inner or abandoned sites and areas,have been analysed by the authors as part of diferent research projects linked with tradition...For more than a decade,a wide range of Spanish case studies,relating especially to rural inner or abandoned sites and areas,have been analysed by the authors as part of diferent research projects linked with traditional and monumen‑tal architecture,conservation strategies and earthen buildings.On one hand the studies have been undertaken in the framework of a project concerning the conservation of rammed earth in the Iberian Peninsula,including criteria,techniques,results and perspectives and,on the other,by a project about the conservation and rehabilitation of tradi‑tional earthen architecture in the Iberian Peninsula,providing guidelines and tools for its sustainable intervention.In all cases the researchers’eforts focused on enhancing new perspectives and opportunities for rural earthen buildings,analysing landscapes,contexts,constructive features,decay and problems.The fnal common aim of this research is to stress these crucial topics to improve tangible or intangible opportunities for conservation strategies.展开更多
文摘There are many problems and deficiencies in traditional bank protection methods,which cause certain damage to the ecological environment of river channels.Recently,the issues of river management,improving bank protection technology,formulating reasonable construction measures,and ensuring the smooth and efficient implementation of construction have been receiving increasing attention.
基金Financial support from the National Key Research and Development Program of China(2017YFE0113500)the National Natu 1 ral Science Foundation of China(51872027 and 51772077)are gratefully acknowledged.
文摘MXenes are a family of two-dimensional (2D) transition metal carbides, carbonitrides/nitrides with superior physical and chemical properties, which have attracted extensive attention since the discovery in 2011. The impressive electrochemical activity of MXene makes it one of the most potential electrode materials in rechargeable batteries and supercapacitors. However, single-component MXene electrodes are difficult to achieve high specific capacity, efficient ion/electron transport, and high stability compatibility in an electrochemical environment. Studies have shown that it is an effective method to introduce nanomaterials between MXene layers to construct heterostructures and to improve the electrochemical performance through the synergistic effect among the components in the heterostructures. The introduction of nanomaterials can effectively suppress the restacking of MXene nanosheets, shorten the diffusion path of ions and promote the electrolyte transport, which is beneficial to enhance the rate performance of MXene;moreover, the excellent mechanical flexibility of MXene can reduce the volume expansion of nanomaterials during charge/discharge, thereby effectively protecting the integrity of the electrode structure and improving the cycling stability. Therefore, in this review, combined with theoretical calculations, we summarize the recent advances of MXene heterostructures in terms of synthesis strategies and energy storage applications, including supercapacitors, metal-ions batteries (Li, Na, K, Mg, Zn, Al) and metal anode protection. Furthermore, potential challenges and application perspectives for MXene heterostructures are also outlined.
文摘Pyramids,symbols of the Ancient Egyptian civilization,are visited by tourists and studied by researchers from all around the world.However,the techniques used by Ancient Egyptians to construct the pyramid,specifically,how such a tall structure could have been constructed from huge blocks of stone with the limited productive forces at the time,remains a mystery to the world.Though numerous theories,such as the use of ramps,levers,pulleys,fluid buoyancy,and cast-in-place concrete,have been proposed in academia,no consensus has been reached to date.Based on mechanical principles and the productive forces available at the time,the famous Pyramid of Khufu is used as a case study in this paper to propose a theory of pit-aided construction.The main steps include the digging of the pit,the transportation of stone blocks into the pit,the layer-by-layer construction,and the layer-by-layer filling of soil until the top of the pyramid is completed.The main idea of the pit-aided construction was to use the self-weight of the stone material to achieve the transportation of stone blocks by converting potential energy to kinetic energy,thereby avoiding the large amounts of work that must be done to elevate the huge blocks of stone.The proposed theory of pit-aided construction is consistent with the cultural custom of burial that is associated with tomb construction,namely laying the deceased to rest through burial,and is also consistent with the productive forces available in Ancient Egypt at the time.
文摘The construction of municipal roads and bridges is an important foundation for the smooth traveling and transportation.However,if there a reduction in the subgrade and pavement part,the safety and the comfort of the driver will be seriously affected,therefore,reasonable measures should be taken on time to tackle the related issues.The significance of subgrade and pavement construction in the subsidence section,the key points of the construction,and the appropriate control measures that are should be taken in the actual construction,was discussed in this paper.Further,this paper analyzes the availability of the subgrade and pavement construction technology for the municipal roads and bridges,to provide a reference for engineers.
文摘Building information modeling(BIM)technology simulates visual information data by integrating the information data of construction projects.The presentation of information parameters allows better collaborative management of the construction process.BIM technology is applied to integrate information data during the construction of prefabricated structures,analyze the source of information data of construction projects,and build a digital information model.BIM technology consists of information integration function,information data simulation,cross-region coordination and more.Therefore,this paper applies it to the process of prefabricated structure design,puts forward relevant technical research strategies,establishes relevant models,ensures the accuracy of drawing,and simulates the final construction effect according to the combination of arranged relevant parameters.
基金supported by the_Izmir Institute of Technology Scientific Research Projects Coordinator(Grant No.2021IYTE-1-0014).
文摘The aim of the study is to present a multi-leveled comparative evaluation approach for structural characteristics of historic masonry monuments so that the consciousness in their authentic designs is comprehended,and the optimum structural performance is clarified.A case study approach is preferred by the examination of the Bedesten(15th‒16th centuries)located in Bergama,_Izmir,Turkey.The structure is documented through tacheometric techniques.The construction techniques of structural elements are mapped.These documented qualities are compared with similar period and/or function structures in order to rank the frequency of construction details.The geometrical factor of safety state is defined theoretically for domes and arches.Finite element macro model of the Bedesten is generated in ANSYS software and overall structural analysis of the structure is made to evaluate the safety level of historic building by the limit states through self-weight analysis.The presented study shows that the rare structural characteristics can both contribute to structural safety and cause vulnerability.Therefore,total consciousness in structural design cannot be stated for the studied Bedesten,but the structural designs that are often preferred in the monuments built at the same period in the proximity to each other have low vulnerability,yielding to conscious preferences.
基金The research project ResTAPIA‘The conservation of rammed earth in the Iberian Peninsula.Criteria,techniques,results and perspectives’(Ref.:BIA 2010-18921)funded by the Spanish Ministry of Science and Innovation.The research project SOStierra‘Restoration and rehabilitation of traditional earthen architecture in the Iberian Peninsula.Guidelines and tools for a sustainable intervention’(Ref.:BIA2014-55924-R)+1 种基金funded by the Spanish Ministry of Science and Innovation.The research project RISK-Terra‘Earthen architecture in the Iberian Peninsula:study of natural,social and anthropic risks and strategies to improve resilience’(Ref.:RTI2018-095302-B-I00)funded by the Spanish Ministry of Science and Innovation.
文摘For more than a decade,a wide range of Spanish case studies,relating especially to rural inner or abandoned sites and areas,have been analysed by the authors as part of diferent research projects linked with traditional and monumen‑tal architecture,conservation strategies and earthen buildings.On one hand the studies have been undertaken in the framework of a project concerning the conservation of rammed earth in the Iberian Peninsula,including criteria,techniques,results and perspectives and,on the other,by a project about the conservation and rehabilitation of tradi‑tional earthen architecture in the Iberian Peninsula,providing guidelines and tools for its sustainable intervention.In all cases the researchers’eforts focused on enhancing new perspectives and opportunities for rural earthen buildings,analysing landscapes,contexts,constructive features,decay and problems.The fnal common aim of this research is to stress these crucial topics to improve tangible or intangible opportunities for conservation strategies.
