Based on the analysis of financial statements,the performance and problems of rural collective economic organizations in their business activities were analyzed.It is believed that rural collective economy was develop...Based on the analysis of financial statements,the performance and problems of rural collective economic organizations in their business activities were analyzed.It is believed that rural collective economy was developing continuously in a good way,with strong debt paying ability,but the operation ability and management efficiency need to be further improved.The operation was too conservative,and the asset utilization efficiency and profitability were weak.There were many unnecessary liabilities,and they developed mainly relying on their own accumulation.Therefore,it is proposed to crack the"talent dilemma"of rural collective economic operation and management,straighten out and clarify the relationship between rural collective economic organizations and villagers self-governing organizations,correctly handle the relationship between collective accumulation and member distribution,adhere to the financial input of blood replenishment and transfusion,and make liabilities reasonable according to the management development.展开更多
During the excavation of deep coal and rock mass, the radial stress of the free face changes from three-dimensional compression state to two-dimensional stress, bearing the combined action of dynamic disturbance and s...During the excavation of deep coal and rock mass, the radial stress of the free face changes from three-dimensional compression state to two-dimensional stress, bearing the combined action of dynamic disturbance and static load at the same time. With that, many mines suffer from dynamic disasters, such as coal and gas outburst, rock burst and rock caving during deep mining excavation, which is often accompanied by plate crack, spalling and other disasters, seriously affecting the stability of stope and roadway. Taking thin rectangular coal and rock mass as the research object, the dual equation of the free vibration was derived and the exact solution model of the free vibration was established with the use of Hamilton dual system. Based on the action characteristics of the uniform impact load, the effective mode of the forced vibration was obtained by using the Duhamel integral principle and the orthogonality of the mode function. Based on the third strength theory and the numerical simulation results, the dynamic damage process and development trend of coal and rock mass were analyzed under uniform impact load. It was concluded that the starting position of dynamic damage can be judged by the first order main mode, and the development direction and trend of the damage can be judged by the fifth and sixth order main modes. It was concluded that the vibration mode functions of coal and rock mass with four side fixed (C-C-C-C), the two sides fixed and simply supported on the other (S-C-S-C) are mainly composed of three modes that are the first order (dominant frequency), the fifth order and the sixth order, from which the dynamic damage mechanism is preliminarily studied.展开更多
As a vital and integral component of transportation infrastructure,pavement has a direct and tangible impact on socio-economic sustainability.In recent years,an influx of groundbreaking and state-of-the-art materials,...As a vital and integral component of transportation infrastructure,pavement has a direct and tangible impact on socio-economic sustainability.In recent years,an influx of groundbreaking and state-of-the-art materials,structures,equipment,and detection technologies related to road engineering have continually and progressively emerged,reshaping the landscape of pavement systems.There is a pressing and growing need for a timely summarization of the current research status and a clear identification of future research directions in these advanced and evolving technologies.Therefore,Journal of Road Engineering has undertaken the significant initiative of introducing a comprehensive review paper with the overarching theme of“advanced road materials,structures,equipment,and detection technologies”.This extensive and insightful review meticulously gathers and synthesizes research findings from 39 distinguished scholars,all of whom are affiliated with 19 renowned universities or research institutions specializing in the diverse and multidimensional field of highway engineering.It covers the current state and anticipates future development directions in the four major and interconnected domains of road engineering:advanced road materials,advanced road structures and performance evaluation,advanced road construction equipment and technology,and advanced road detection and assessment technologies.展开更多
Wearable devices redefine the way people interact with machines.Despite the intensive effort in the design and fabrication of synthetic fibers to improve wearable device properties in terms of electronic and ionic con...Wearable devices redefine the way people interact with machines.Despite the intensive effort in the design and fabrication of synthetic fibers to improve wearable device properties in terms of electronic and ionic conductivity,stretchability,com-fort,and washability,challenges remain in fabricating single fiber materials that optimize all properties simultaneously.In this work,we demonstrate a highly stretchable,ionic,and electronic conductive fabric via(1)the natural nanoscale chan-nels in fibers for effective ion transportation,(2)confining the electronic conductive material with the cellulose fibers,and(3)decoupling the property degradation of the fiber from deformation using the knitted pattern.The hierarchical structure created by cotton fibers can serve as ionic conductive channels as well as a robust multiscale scaffold to host infiltrated elec-tronic conductive materials.Cotton strands with ionic and electronic conductivity can be knitted into fabrics that are highly stretchable(~300%).Moreover,high ionic and electronic conductivity are observed with 2 S/m and 5 S/m,respectively,even under a strain of 175%.With the inherent advantages of cotton fabrics such as moisture-wicking,washability,comfort,and light-weightiness for wearable applications,our approach of directly functionalized cellulose can potentially be a promising route towards highly stretchable and wearable mixed conductors.展开更多
基金Supported by the Scientific Research Project for College Students of Hubei University of Economics in 2022.
文摘Based on the analysis of financial statements,the performance and problems of rural collective economic organizations in their business activities were analyzed.It is believed that rural collective economy was developing continuously in a good way,with strong debt paying ability,but the operation ability and management efficiency need to be further improved.The operation was too conservative,and the asset utilization efficiency and profitability were weak.There were many unnecessary liabilities,and they developed mainly relying on their own accumulation.Therefore,it is proposed to crack the"talent dilemma"of rural collective economic operation and management,straighten out and clarify the relationship between rural collective economic organizations and villagers self-governing organizations,correctly handle the relationship between collective accumulation and member distribution,adhere to the financial input of blood replenishment and transfusion,and make liabilities reasonable according to the management development.
文摘During the excavation of deep coal and rock mass, the radial stress of the free face changes from three-dimensional compression state to two-dimensional stress, bearing the combined action of dynamic disturbance and static load at the same time. With that, many mines suffer from dynamic disasters, such as coal and gas outburst, rock burst and rock caving during deep mining excavation, which is often accompanied by plate crack, spalling and other disasters, seriously affecting the stability of stope and roadway. Taking thin rectangular coal and rock mass as the research object, the dual equation of the free vibration was derived and the exact solution model of the free vibration was established with the use of Hamilton dual system. Based on the action characteristics of the uniform impact load, the effective mode of the forced vibration was obtained by using the Duhamel integral principle and the orthogonality of the mode function. Based on the third strength theory and the numerical simulation results, the dynamic damage process and development trend of coal and rock mass were analyzed under uniform impact load. It was concluded that the starting position of dynamic damage can be judged by the first order main mode, and the development direction and trend of the damage can be judged by the fifth and sixth order main modes. It was concluded that the vibration mode functions of coal and rock mass with four side fixed (C-C-C-C), the two sides fixed and simply supported on the other (S-C-S-C) are mainly composed of three modes that are the first order (dominant frequency), the fifth order and the sixth order, from which the dynamic damage mechanism is preliminarily studied.
基金support from the European Union's Horizon 2020 Research and Innovation Program under the Marie Skłodowska-Curie grant agreement No.101024139,the RILEM technical committee TC 279 WMR(valorisation of waste and secondary materials for roads),RILEM technical committee TC-264 RAP(asphalt pavement recycling)the Swiss National Science Foundation(SNF)grant 205121_178991/1 for the project titled“Urban Mining for Low Noise Urban Roads and Optimized Design of Street Canyons”,National Natural Science Foundation of China(No.51808462,51978547,52005048,52108394,52178414,52208420,52278448,52308447,52378429)+9 种基金China Postdoctoral Science Foundation(No.2023M730356)National Key R&D Program of China(No.2021YFB2601302)Natural Science Basic Research Program of Shaanxi(Program No.2023-JC-QN-0472)Postdoctoral Science Foundation of Anhui Province(2022B627)Shaanxi Provincial Science and Technology Department(No.2022 PT30)Key Technological Special Project of Xinxiang City(No.22ZD013)Key Laboratory of Intelligent Manufacturing of Construction Machinery(No.IMCM2021KF02)the Applied Basic Research Project of Sichuan Science and Technology Department(Free Exploration Type)(Grant No.2020YJ0039)Key R&D Support Plan of Chengdu Science and Technology Project-Technology Innovation R&D Project(Grant No.2019-YF05-00002-SN)the China Postdoctoral Science Foundation(Grant No.2018M643520).
文摘As a vital and integral component of transportation infrastructure,pavement has a direct and tangible impact on socio-economic sustainability.In recent years,an influx of groundbreaking and state-of-the-art materials,structures,equipment,and detection technologies related to road engineering have continually and progressively emerged,reshaping the landscape of pavement systems.There is a pressing and growing need for a timely summarization of the current research status and a clear identification of future research directions in these advanced and evolving technologies.Therefore,Journal of Road Engineering has undertaken the significant initiative of introducing a comprehensive review paper with the overarching theme of“advanced road materials,structures,equipment,and detection technologies”.This extensive and insightful review meticulously gathers and synthesizes research findings from 39 distinguished scholars,all of whom are affiliated with 19 renowned universities or research institutions specializing in the diverse and multidimensional field of highway engineering.It covers the current state and anticipates future development directions in the four major and interconnected domains of road engineering:advanced road materials,advanced road structures and performance evaluation,advanced road construction equipment and technology,and advanced road detection and assessment technologies.
文摘Wearable devices redefine the way people interact with machines.Despite the intensive effort in the design and fabrication of synthetic fibers to improve wearable device properties in terms of electronic and ionic conductivity,stretchability,com-fort,and washability,challenges remain in fabricating single fiber materials that optimize all properties simultaneously.In this work,we demonstrate a highly stretchable,ionic,and electronic conductive fabric via(1)the natural nanoscale chan-nels in fibers for effective ion transportation,(2)confining the electronic conductive material with the cellulose fibers,and(3)decoupling the property degradation of the fiber from deformation using the knitted pattern.The hierarchical structure created by cotton fibers can serve as ionic conductive channels as well as a robust multiscale scaffold to host infiltrated elec-tronic conductive materials.Cotton strands with ionic and electronic conductivity can be knitted into fabrics that are highly stretchable(~300%).Moreover,high ionic and electronic conductivity are observed with 2 S/m and 5 S/m,respectively,even under a strain of 175%.With the inherent advantages of cotton fabrics such as moisture-wicking,washability,comfort,and light-weightiness for wearable applications,our approach of directly functionalized cellulose can potentially be a promising route towards highly stretchable and wearable mixed conductors.
