In this study,the hydraulic behavior and sand transport efficiency of the siphon automatic sand discharge device were studied by software simulation tests.By simulating the actual situation,this study analyzed how fac...In this study,the hydraulic behavior and sand transport efficiency of the siphon automatic sand discharge device were studied by software simulation tests.By simulating the actual situation,this study analyzed how factors such as the difference in water level,sediment concentration,and pipeline layout affected the sediment discharge effect.The results show that the sediment discharge device can effectively discharge sediment under diverse operating conditions and show adaptability to different environmental conditions,which indicates that it is suitable for various types of reservoir environments.展开更多
It is urgent and important to explore the dynamic evolution in comprehensive transportation green efficiency(CTGE)in the context of green development.We constructed a social development index that reflects the social ...It is urgent and important to explore the dynamic evolution in comprehensive transportation green efficiency(CTGE)in the context of green development.We constructed a social development index that reflects the social benefits of transportation services,and incorporated it into the comprehensive transportation efficiency evaluation framework as an expected output.Based on the panel data of 30 regions in China from 2003-2018,the CTGE in China was measured using the slacks-based measure-data envelopment analysis(SBM-DEA)model.Further,the dynamic evolution trends of CTGE were determined using the spatial Markov model and exploratory spatio-temporal data analysis(ESTDA)technique from a spatio-temporal perspective.The results showed that the CTGE shows a U-shaped change trend but with an overall low level and significant regional differences.The state transition of CTGE has a strong spatial dependence,and there exists the phenomenon of“club convergence”.Neighbourhood background has a significant impact on the CTGE transition types,and the spatial spillover effect is pronounced.The CTGE has an obvious positive correlation and spatial agglomeration characteristics.The geometric characteristics of the LISA time path show that the evolution process of local spatial structure and local spatial dependence of China’s CTGE is stable,but the integration of spatial evolution is weak.The spatio-temporal transition results of LISA indicate that the CTGE has obvious transfer inertness and has certain path-dependence and spatial locking characteristics,which will become the major difficulty in improving the CTGE.展开更多
Grasping the spatial correlation structure of transportation carbon emission efficiency(TCEE)and its influencing factors is significant for promoting high-quality and coordinated development of the transportation indu...Grasping the spatial correlation structure of transportation carbon emission efficiency(TCEE)and its influencing factors is significant for promoting high-quality and coordinated development of the transportation industry and the relevant region.Based on the ideal point cross-efficiency(IPCE)model,the social network analysis method was employed herein to explore the spatial correlation network structure of China’s provincial TCEE and its influencing factors.The results obtained showed the following outcomes.(1)During the study period,China’s provincial TCEE formed a complex and multithreaded network association relationship,but its network association structure was still relatively loose and presented the hierarchical gradient characteristics of dense in the east and sparse in the west.(2)The correlation of China’s TCEE formed a block segmentation based on the regional boundaries,and its factional structure was relatively obvious.The eastern region was closely connected with the central region,and generally connected with the western and northeastern regions.The central region was mainly connected with the eastern and western regions,and relatively less connected with the northeastern region.Besides,the northeastern region was weakly connected with the western region.(3)Shanghai,Beijing,Zhejiang,Guangdong,Jiangsu,Tianjin,and other developed provinces were in the core leading position in the TCEE network,which significantly impacted the spatial correlation of TCEE.However,Heilongjiang,Jilin,Xinjiang,Qinghai,and other remote provinces in the northeast and northwest were at the absolute edge of the network,which weakly impacted the spatial correlation of TCEE.(4)Provincial distance,economic development-level difference,transportation intensity difference,and transportation structure difference had significant negative impacts on the spatial correlation network of China’s provincial TCEE.In contrast,the energy-saving technology level difference had a significant positive impact on it.The regression coefficients of transportation energy structure and environmental regulation differences were positive but insignificant;their response mechanism and effects need to be improved and enhanced.展开更多
To improve the efficiency of ship traffic in frequently traded sea areas and respond to the national“dual-carbon”strategy,a multi-objective ship route induction model is proposed.Considering the energy-saving and en...To improve the efficiency of ship traffic in frequently traded sea areas and respond to the national“dual-carbon”strategy,a multi-objective ship route induction model is proposed.Considering the energy-saving and environmental issues of ships,this study aims to improve the transportation efficiency of ships by providing a ship route induction method.Ship data from a certain bay during a defined period are collected,and an improved backpropagation neural network algorithm is used to forecast ship traffic.On the basis of the forecasted data and ship route induction objectives,dynamic programming of ship routes is performed.Experimental results show that the routes planned using this induction method reduce the combined cost by 17.55%compared with statically induced routes.This method has promising engineering applications in improving ship navigation efficiency,promoting energy conservation,and reducing emissions.展开更多
Anion exchange membranes(AEMs)combining high hydroxide conductivity and alkali-resistant stability have become a major challenge for the long-term development of anion exchange membrane fuel cells(AEMFCs).Here,we desi...Anion exchange membranes(AEMs)combining high hydroxide conductivity and alkali-resistant stability have become a major challenge for the long-term development of anion exchange membrane fuel cells(AEMFCs).Here,we designed a series of poly(mequitazine-terphenyl piperidinium)(QPMTP-X)AEMs with dual-functionalized quaternary ammonium cations by introducing a certain proportion of large steric hindrance mequitazine(MEQ)molecular building unit into the poly(aryl piperidinium)backbone.QPMTP-X retains the excellent mechanical properties of the poly(aryl piperidinium),while also combining the alkaline stability and high ionic conductivity exhibited by MEQ with flexible quinuclidinium side chains,achieving an overall improvement of membrane performance.Notably,QPMTP-30 exhibits an ultra-high conductivity of up to 206.83 mS cm^(-1)and excellent alkaline stability(over 95%conductivity is maintained after 1000 h of conditioning in 2 M NaOH at 80℃).In fuel cell performance test,QPMTP-30 achieves a peak power density(PPD)of 974.5 mW cm^(-2)and operates stably at 80℃for more than 60 h(0.1 A cm^(-2)).Incorporating large steric hindrance building blocks and multi-cations into the poly(aryl piperidinium)backbone not only synergizes the development of highperformance AEMs but also opens up new ideas for the structural design of future AEMs.展开更多
Inverted perovskite solar cells(PSCs)have stood out in recent years for their great potential in offering low-temperature compatibility,long-term stability and tandem cell suitability.However,challenges persist,partic...Inverted perovskite solar cells(PSCs)have stood out in recent years for their great potential in offering low-temperature compatibility,long-term stability and tandem cell suitability.However,challenges persist,particularly concerning the use of nickel oxide nanoparticles(NiO_(x)NPs)as the hole transport material,where issues such as low conductivity,impurity-induced aggregation and interface redox reactions significantly hinder device performance.In response,this study presents a novel synthesis method for NiO_(x)NPs,leveraging the introduction of ammonium salt dopants(NH_(4)Cl and NH_(4)SCN),and the solar cell utilizing the doped NiO_(x)substrate exhibits much enhanced device performance.Furthermore,doped solar cells reach 23.27%power conversion efficiency(PCE)when a self-assembled monolayer(SAM)is further employed.This study provides critical insights into the synthesis and growth pathways of NiO_(x)NPs,propelling the development of efficient hole transport materials for high-performance PSCs.展开更多
Transportation accounts for 80% of open-cut coal mine carbon emissions. With regard to the energy con- sumption and carbon emissions of transportation within an open-cut mine, this paper systematically compared the wo...Transportation accounts for 80% of open-cut coal mine carbon emissions. With regard to the energy con- sumption and carbon emissions of transportation within an open-cut mine, this paper systematically compared the work and energy consumption of a truck and belt conveyor on a theoretical basis, and con- structed a model to calculate the energy consumption of open-cut mine transportation. Life cycle carbon emission factors and power consumption calculation model were established through a Process Analysis- Life Cycle Analysis （PA-LCA）. The following results were obtained： （1） the energy consumption of truck transportation was four to twelve times higher than that of the belt conveyor; （2） the C02 emissions from truck transportation were three to ten times higher than those of the belt conveyor; （3） with the increase in the slope angle for transportation, the ratio of truck to belt conveyor for both energy consumption and carbon emissions gradually decreased; （4） based on 2013 prices in China, the energy cost of transportation using a belt conveyor in open-cut coal mines could save 0.6-2.4 Yuan/（t kin） compared to truck transportation.展开更多
Ice cores contain an abundance of information about the Earth＇s climate in the past, and recovered from shallow drilling down to 300-350 m give sufficient information for reconstructing of the last climatic changes a...Ice cores contain an abundance of information about the Earth＇s climate in the past, and recovered from shallow drilling down to 300-350 m give sufficient information for reconstructing of the last climatic changes and for monitoring of pollution from human being. Cable-suspended core auger drills use an armored cable with a winch to provide power to the down-hole motor system and to retrieve the down-hole unit. Because of their lightweight, convenient transportation and installation, high penetration rates and low power consumption, core auger drills are widely used for shallow drilling in ice. Nowadays at least 14 types of auger electromechani- cal drills were designed and tested in different foreign and national glaciological laboratories. However, auger options were usually determined by experience, and the main parameters （ helix angle of the fights and rotational speed） are varied in a wide range from drill to drill. If parameters of auger are not chosen properly, poorly en- gineered drills had troubles with low efficiency of cuttings transportation, jam of ice cuttings, repeated fragmen- tation, cutters icing and stop penetration, abnormal power consumption, high rotation torques, and so on. Thus, this paper presents the method of optimization of iee cuttings transportation of cable-suspended core auger drill on the base of the theory of rotary auger. As the result, the optimal helix angle was determined correspond- ing to the rotational speed from the transportation efficiency point of view.展开更多
The article describes the possibilities of application of simulation modeling for the analysis of infrastructure and technology of transport services of enterprises. The main technological and possible economic effect...The article describes the possibilities of application of simulation modeling for the analysis of infrastructure and technology of transport services of enterprises. The main technological and possible economic effects for the enterprises arising at performance of modeling of a transport component of their work are resulted.展开更多
In recent years the photovoltaic community has witnessed the unprecedented development of perovskite solar cells（PSCs） as they have taken the lead in emergent photovoltaic technologies. The power conversion efficien...In recent years the photovoltaic community has witnessed the unprecedented development of perovskite solar cells（PSCs） as they have taken the lead in emergent photovoltaic technologies. The power conversion efficiency of this new class of solar cells has been increased to a point where they are beginning to compete with more established technologies. Although PSCs have evolved a variety of structures, the use of hole-transporting materials（HTMs） remains indispensable. Here, an overview of the various types of available HTMs is presented. This includes organic and inorganic HTMs and is presented alongside recent progress in associated aspects of PSCs, including device architectures and fabrication techniques to produce high-quality perovskite films. The structure, electrochemistry, and physical properties of a variety of HTMs are discussed, highlighting considerations for those designing new HTMs. Finally, an outlook is presented to provide more concrete direction for the development and optimization of HTMs for highefficiency PSCs.展开更多
Nanostructured TiO2 with differentiate morphologies has attracted tremendous attention due to its wide band-gap nature as well as outstanding optical and electric properties for solar-driven light-toelectricity conver...Nanostructured TiO2 with differentiate morphologies has attracted tremendous attention due to its wide band-gap nature as well as outstanding optical and electric properties for solar-driven light-toelectricity conversion application. Layered-stacking TiO2 film such as double-layer, tri-layer, quadrupleor quintuplicate-layer, is highly desirable to the design of high-performance semiconductor material photoanodes and the development of advanced photovoltaic devices. In this minireview, we will summarize the recent progress and achievements on proof-of-concept of layered-stacking TiO2 films（LTFs） for solar cells with emphasis on the tailored properties and synergistic functionalization of LTFs, such as optimized sensitizer adsorption, broadened light confinement as well as facilitated electron transport characteristics.Various demonstrations of LTFs photovoltaic systems provide lots of possibilities and flexibilities for more efficient solar energy utilization that a wide variety of TiO2 with distinguished morphologies can be integrated into differently structured photoanodes with synergistic and complementary advantages. This key structure engineering technology will also pave the way for the development of next generation state-ofthe-art electronics and optoelectronics. Finally, from our point of view, we conclude the future research interest and efforts for constructing more efficient LTFs as photoelectrode, which will be highly warranted to advance the solar energy conversion process.展开更多
Based on the transmission line code TLCODE, a 1D circuit model for a transmission- line impedance transformer was developed and the simulation results were compared with those in the literature. The model was used to ...Based on the transmission line code TLCODE, a 1D circuit model for a transmission- line impedance transformer was developed and the simulation results were compared with those in the literature. The model was used to quantify the efficiencies of voltage-transport, energy- transport and power-transport for a transmission-line impedance transformer as functions of ψ （the ratio of the output impedance to the input impedance of the transformer） and Г （the ratio of the pulse width to the one-way transit time of the transformer） under a large scale of m （the coefficient of the generalized exponential impedance profile）. Simulation results suggest that with the increase in Г, from 0 to ∞, the power transport efficiency first increases and then decreases. The maximum power transport efficiency can reach 90% or even higher for an exponential impedance profile （m = 1）. With a consideration of dissipative loss in the dielectric and electrodes of the transformer, two representative designs of the water-insulated transformer are investigated for the next generation of petawatt-class z-pinch drivers. It is found that the dissipative losses in the electrodes are negligibly small, below 0.1%, but the dissipative loss in the water dielectric is about 1% to 4%.展开更多
Titanylphthalocyanine （TiOPc） as hole transporting material （HTM） was successfully synthesized by a simple process with low cost. Perovskite solar cells using the TiOPc as HTM were fabricated and characterized. Ti...Titanylphthalocyanine （TiOPc） as hole transporting material （HTM） was successfully synthesized by a simple process with low cost. Perovskite solar cells using the TiOPc as HTM were fabricated and characterized. TiOPc as HTM plays an important role in increasing the power conversion efficiency （PCE） by minimizing recombi- nation losses at the perovskite/Au interface because TiOPc as HTM can extract photogenerated holes from the perovskite and then transport quickly these charges to the back metal electrode. In the research, the β-TiOPc gives a higher PCE than α-TiOPc for the devices due to sufficient transfer dynamics, The β-TiOPc was applied in perovskite solar cells without clopping to afford an impressive PCE of 5.05% under AM 1.5G illumination at the thickness of 40 nm which is competitive with spiro-OMeTAD at the same condition. The present work suggests a guideline for optimizing the photovoltaic properties ofperovskite solar cells using the TiOPc as the HTM.展开更多
In this review, we highlight the recent development of organic π-functional materials as buffer layers in constructing efficient perovskite solar cells（PVSCs）. By following a brief introduction on the PVSC developm...In this review, we highlight the recent development of organic π-functional materials as buffer layers in constructing efficient perovskite solar cells（PVSCs）. By following a brief introduction on the PVSC development, device architecture and material design features, we exemplified the exciting progresses made in field by exploiting organic π-functional materials based hole and electron transport layers（HTLs and ETLs） to enable high-performance PVSCs.展开更多
In this study, we report narrow-size distribution Zn_2SnO_4（ZSO） nanoparticles, which are produced by low-temperature solution-processed used as the electron extraction layer（EEL） in the inverted polymer solar ce...In this study, we report narrow-size distribution Zn_2SnO_4（ZSO） nanoparticles, which are produced by low-temperature solution-processed used as the electron extraction layer（EEL） in the inverted polymer solar cells（i-PSCs）. Moreover, poly[（9,9-bis（30-（N,N-dimethylamino）propyl）-2,7-fluorene）-alt-2,7-（9,9-dioctylfluorene）]（PFN） is used to modify the surface properties of ZSO thin film. By using the ZSO NPs/PFN as the EEL, the i-PSCs fabricated by poly[4,8-bis（2-ethylhexyloxyl）benzo[1,2-b：4,5-b0] dithio-phene-2,6-diyl-altethylhexyl-3-fluorothithieno [3,4-b]thiophene-2-carboxylate-4,6-diyl]（PTB7） blended with（6,6）-phenyl-C_（71）-butyric acid methylester（PC_（71）BM） bulk heterojunction（BHJ） composite, exhibits a power conversion efficiency（PCE） of 8.44%, which is nearly 10% enhancement as compared with that of7.75% observed from the i-PSCs by PTB7：PC_（71）BM BHJ composite using the ZnO/PFN EEL. The enhanced PCE is originated from improved interfacial contact between the EEL with BHJ active layer and good energy level alignment between BHJ active layer and the EEL. Our results indicate that we provide a simple way to boost efficiency of i-PSCs.展开更多
Solid-state batteries(SSBs)are considered as the next-generation battery technology,poised to deliver both high energy and enhanced safety.Nonetheless,their transition from laboratory to market is impeded by several c...Solid-state batteries(SSBs)are considered as the next-generation battery technology,poised to deliver both high energy and enhanced safety.Nonetheless,their transition from laboratory to market is impeded by several critical challenges.Among these,the solid–solid interfaces within SSBs represent a bottleneck,characterized by issues such as poor physical contact,side reactions,temporal separation,and sluggish charge carrier transfer.Developing key materials to construct the efficient solid–solid interface is critical for building high-performance SSBs.Organic mixed ionic–electronic conductors(OMIECs)have emerged as a promising alternative to conventional conductors in addressing the abovementioned issues owing to their intrinsic properties,including the capability of conducting both ions and electrons,mechanical flexibility,and structural designability.This review will first elucidate the necessity of the integration of OMIECs in SSBs.Next,a comprehensive exploration of the composition,preparation methods,key advantages,and basic characterizations of OMIECs is presented.This review then delves into recent research progress on OMIECs in SSBs,with a special focus on their application in cathode coating layers,the creation of a 3D mixed conductive framework for Li hosting,and their integration as inner layers in Li anodes.Conclusively,potential future applications and innovative designs of OMIECs are discussed.展开更多
The rational design of a heterostructural photocatalysts with efficient charge separation and accelerated interfacial charge transfer holds great promise for boosting photocatalytic activity.Herein,we have developed a...The rational design of a heterostructural photocatalysts with efficient charge separation and accelerated interfacial charge transfer holds great promise for boosting photocatalytic activity.Herein,we have developed a unique hierarchical In_(4/3)P_(2)S_(6)/TiO_(2) heterojunction with P-O interfacial bonding for photocatalytic water reduction.By integrating emerging In_(4/3)P_(2)S_(6) nanosheets through intense interfacial coupling effect,the optimized In_(4/3)P_(2)S_(6)/TiO_(2) heterostructure exhibits a remarkably enhanced photocatalytic H2 evolution activity compared to that of pristine TiO_(2).Combined experimental and theoretical results confirm that multiple interfacial bonded step-scheme(S-scheme)charge transfer pathways are established in the In_(4/3)P_(2)S_(6)/TiO_(2) photocatalyst,which synergistically promote charge separation and transfer through the robust interfacial electric field and rapid charge migration pathways formed by interfacial bonds.This study emphasizes the significance of developing novel interfacial bonded In_(4/3)P_(2)S_(6)-based S-scheme heterostructures,paving a new strategy towards enhancing photocatalytic activity for H_(2) evolution.展开更多
A concise definition of Transport Efficiency (TE) was given to examine the amount of transported grains in the pipe flow with certain energy consumption. The transport characteristics and the so-called 'roto-float...A concise definition of Transport Efficiency (TE) was given to examine the amount of transported grains in the pipe flow with certain energy consumption. The transport characteristics and the so-called 'roto-floating' characteristics were studied from the tests of sediment transport in the normal pipe flow and the spiral pipe flow, and hereby the energy gradients of the two kinds of pipe flows were obtained. By comparing the mean concentrations at the same gradient, it was concluded that the TE of the latter is several times to over ten times higher than that of the former, and the lift of the latter is 200 times larger than that of the former for the nearly same TE. The spiral flow in circular pipe is suitable for transporting fine grains of high concentration, and with sedimentation trend and coarse grains.展开更多
Research interest in pneumatic conveying technologies in processes such as peanut harvesting and shelling has grown rapidly in recent years.However,the use of pneumatic conveyors in this application suffers from high ...Research interest in pneumatic conveying technologies in processes such as peanut harvesting and shelling has grown rapidly in recent years.However,the use of pneumatic conveyors in this application suffers from high pod damage rates and duct obstruction.To address these issues,we analyzed the critical speed of pneumatic transport for conveying the peanut pods and measured the angle of friction and coefficient of restitution of peanut pods on a variety of material surfaces.Based on the results of these tests,optimizations and improvements were made to the separator bowl,air supply duct,and conveying duct.A pneumatic conveying experiment was then performed using peanut pods.In the factorial experiment,it was found that increases in fan speed increase the pod damage rate and transport efficiency,while increases in the thickness of the cushioning/anti-obstruction layer decrease the rate of pod damage and transport efficiency.Pod damage rates were significantly affected by fan speed,the thickness of the cushioning/obstruction prevention layer,and interaction between these factors,while transport efficiency was only significantly affected by fan speed.It is proved by the machine verification test,the optimal parameters for the pneumatic transport of Baisha peanut pods with a moisture content of 7.24%was a fan speed of 2700 r/min and a cushioning/anti-obstruction layer thickness of 6 mm.A pod damage rate of 5.19%and transport efficiency of 92.03%were achieved using these parameters,which are sufficient for meeting the requirements of industrial applications.展开更多
The Beijing intense slow positron beam facility is based on the 1.3 GeV linac of Beijing ElectronPositron Collider （BEPC） aiming to produce mono-energetic intense slow positron beam for material science investigatio...The Beijing intense slow positron beam facility is based on the 1.3 GeV linac of Beijing ElectronPositron Collider （BEPC） aiming to produce mono-energetic intense slow positron beam for material science investigation. The plugged-in 22Na based slow positron beam section has been newly constructed to supply continuous beam time for the debugging of positron annihilation measurement stations and improve the Beijing intense slow positron beam time using efficiency. Performance testing result of the plugged-in 22Na based slow positron beam facility are reviewed in this paper, with the measurement of the beam transport efficiency, the view of beam spot, the adjustment of beam position, the measurement of beam intensity and energy spread etc. included.展开更多
基金Supported by the National Undergraduate Innovation Training Program(Project No.202211437036).
文摘In this study,the hydraulic behavior and sand transport efficiency of the siphon automatic sand discharge device were studied by software simulation tests.By simulating the actual situation,this study analyzed how factors such as the difference in water level,sediment concentration,and pipeline layout affected the sediment discharge effect.The results show that the sediment discharge device can effectively discharge sediment under diverse operating conditions and show adaptability to different environmental conditions,which indicates that it is suitable for various types of reservoir environments.
基金National Key Research and Development Program of China(2019YFB1600400)National Natural Science Foundation of China(72174035)+2 种基金National Natural Science Foundation of China(71774018)Liaoning Revitalization Talents Program(XLYC2008030)Liaoning Provincial Natural Science Foundation Shipping Joint Foundation Program(2020-HYLH-20)。
文摘It is urgent and important to explore the dynamic evolution in comprehensive transportation green efficiency(CTGE)in the context of green development.We constructed a social development index that reflects the social benefits of transportation services,and incorporated it into the comprehensive transportation efficiency evaluation framework as an expected output.Based on the panel data of 30 regions in China from 2003-2018,the CTGE in China was measured using the slacks-based measure-data envelopment analysis(SBM-DEA)model.Further,the dynamic evolution trends of CTGE were determined using the spatial Markov model and exploratory spatio-temporal data analysis(ESTDA)technique from a spatio-temporal perspective.The results showed that the CTGE shows a U-shaped change trend but with an overall low level and significant regional differences.The state transition of CTGE has a strong spatial dependence,and there exists the phenomenon of“club convergence”.Neighbourhood background has a significant impact on the CTGE transition types,and the spatial spillover effect is pronounced.The CTGE has an obvious positive correlation and spatial agglomeration characteristics.The geometric characteristics of the LISA time path show that the evolution process of local spatial structure and local spatial dependence of China’s CTGE is stable,but the integration of spatial evolution is weak.The spatio-temporal transition results of LISA indicate that the CTGE has obvious transfer inertness and has certain path-dependence and spatial locking characteristics,which will become the major difficulty in improving the CTGE.
基金This research was funded by the National Science Foundation under the Project“Synergic evolution mechanism of intercity transportation and metropolitan tourism spatial pattern”[Grant number.41771162]It was also funded by the National First-Class Discipline Development Project in Hunan Province under the category of“Geography”[Grang number.510002].
文摘Grasping the spatial correlation structure of transportation carbon emission efficiency(TCEE)and its influencing factors is significant for promoting high-quality and coordinated development of the transportation industry and the relevant region.Based on the ideal point cross-efficiency(IPCE)model,the social network analysis method was employed herein to explore the spatial correlation network structure of China’s provincial TCEE and its influencing factors.The results obtained showed the following outcomes.(1)During the study period,China’s provincial TCEE formed a complex and multithreaded network association relationship,but its network association structure was still relatively loose and presented the hierarchical gradient characteristics of dense in the east and sparse in the west.(2)The correlation of China’s TCEE formed a block segmentation based on the regional boundaries,and its factional structure was relatively obvious.The eastern region was closely connected with the central region,and generally connected with the western and northeastern regions.The central region was mainly connected with the eastern and western regions,and relatively less connected with the northeastern region.Besides,the northeastern region was weakly connected with the western region.(3)Shanghai,Beijing,Zhejiang,Guangdong,Jiangsu,Tianjin,and other developed provinces were in the core leading position in the TCEE network,which significantly impacted the spatial correlation of TCEE.However,Heilongjiang,Jilin,Xinjiang,Qinghai,and other remote provinces in the northeast and northwest were at the absolute edge of the network,which weakly impacted the spatial correlation of TCEE.(4)Provincial distance,economic development-level difference,transportation intensity difference,and transportation structure difference had significant negative impacts on the spatial correlation network of China’s provincial TCEE.In contrast,the energy-saving technology level difference had a significant positive impact on it.The regression coefficients of transportation energy structure and environmental regulation differences were positive but insignificant;their response mechanism and effects need to be improved and enhanced.
基金Supported by the National Key R&D Program of China project (2017YFC0805309)the National Natural Science Foundation of China (60602020)。
文摘To improve the efficiency of ship traffic in frequently traded sea areas and respond to the national“dual-carbon”strategy,a multi-objective ship route induction model is proposed.Considering the energy-saving and environmental issues of ships,this study aims to improve the transportation efficiency of ships by providing a ship route induction method.Ship data from a certain bay during a defined period are collected,and an improved backpropagation neural network algorithm is used to forecast ship traffic.On the basis of the forecasted data and ship route induction objectives,dynamic programming of ship routes is performed.Experimental results show that the routes planned using this induction method reduce the combined cost by 17.55%compared with statically induced routes.This method has promising engineering applications in improving ship navigation efficiency,promoting energy conservation,and reducing emissions.
基金financial support of this work by the Natural Science Foundation of China(Grant Nos.U24A20505,52473205)Chang Bai Mountain Scholars Program of Jilin Province and Jilin Provincial Science&Technology Department(Grant No.YDZJ202401357).
文摘Anion exchange membranes(AEMs)combining high hydroxide conductivity and alkali-resistant stability have become a major challenge for the long-term development of anion exchange membrane fuel cells(AEMFCs).Here,we designed a series of poly(mequitazine-terphenyl piperidinium)(QPMTP-X)AEMs with dual-functionalized quaternary ammonium cations by introducing a certain proportion of large steric hindrance mequitazine(MEQ)molecular building unit into the poly(aryl piperidinium)backbone.QPMTP-X retains the excellent mechanical properties of the poly(aryl piperidinium),while also combining the alkaline stability and high ionic conductivity exhibited by MEQ with flexible quinuclidinium side chains,achieving an overall improvement of membrane performance.Notably,QPMTP-30 exhibits an ultra-high conductivity of up to 206.83 mS cm^(-1)and excellent alkaline stability(over 95%conductivity is maintained after 1000 h of conditioning in 2 M NaOH at 80℃).In fuel cell performance test,QPMTP-30 achieves a peak power density(PPD)of 974.5 mW cm^(-2)and operates stably at 80℃for more than 60 h(0.1 A cm^(-2)).Incorporating large steric hindrance building blocks and multi-cations into the poly(aryl piperidinium)backbone not only synergizes the development of highperformance AEMs but also opens up new ideas for the structural design of future AEMs.
基金supported by the Open Research Fund of Songshan Lake Materials Laboratory(No.2021SLABFK09)the National Natural Science Foundation of China(No.22109093)+1 种基金the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning and the Shanghai Rising-Star Program(No.19QA1403800)the Project of Innovative Development Agency of Republic of Uzbekistan(No.FZ-20200929177)and Shanghai Technical Service Computing Center of Science and Engineering,Shanghai University.
文摘Inverted perovskite solar cells(PSCs)have stood out in recent years for their great potential in offering low-temperature compatibility,long-term stability and tandem cell suitability.However,challenges persist,particularly concerning the use of nickel oxide nanoparticles(NiO_(x)NPs)as the hole transport material,where issues such as low conductivity,impurity-induced aggregation and interface redox reactions significantly hinder device performance.In response,this study presents a novel synthesis method for NiO_(x)NPs,leveraging the introduction of ammonium salt dopants(NH_(4)Cl and NH_(4)SCN),and the solar cell utilizing the doped NiO_(x)substrate exhibits much enhanced device performance.Furthermore,doped solar cells reach 23.27%power conversion efficiency(PCE)when a self-assembled monolayer(SAM)is further employed.This study provides critical insights into the synthesis and growth pathways of NiO_(x)NPs,propelling the development of efficient hole transport materials for high-performance PSCs.
基金supported by the key project of the National Natural Science Foundation of China(No.51034005)the Research Fund for the Doctoral Program of Higher Education(the Specialized Research Fund for the Doctoral Program of Higher Education of China)(No.20100095110019)+1 种基金the National‘‘Twelfth Five-Year’’Plan for Science&Technology Support(No.2014BAC14B00)the National High Technology Research and Development Program of China(No.2012AA062004)
文摘Transportation accounts for 80% of open-cut coal mine carbon emissions. With regard to the energy con- sumption and carbon emissions of transportation within an open-cut mine, this paper systematically compared the work and energy consumption of a truck and belt conveyor on a theoretical basis, and con- structed a model to calculate the energy consumption of open-cut mine transportation. Life cycle carbon emission factors and power consumption calculation model were established through a Process Analysis- Life Cycle Analysis （PA-LCA）. The following results were obtained： （1） the energy consumption of truck transportation was four to twelve times higher than that of the belt conveyor; （2） the C02 emissions from truck transportation were three to ten times higher than those of the belt conveyor; （3） with the increase in the slope angle for transportation, the ratio of truck to belt conveyor for both energy consumption and carbon emissions gradually decreased; （4） based on 2013 prices in China, the energy cost of transportation using a belt conveyor in open-cut coal mines could save 0.6-2.4 Yuan/（t kin） compared to truck transportation.
基金Supported by Project of the National Science Foundation of China(No.41327804)
文摘Ice cores contain an abundance of information about the Earth＇s climate in the past, and recovered from shallow drilling down to 300-350 m give sufficient information for reconstructing of the last climatic changes and for monitoring of pollution from human being. Cable-suspended core auger drills use an armored cable with a winch to provide power to the down-hole motor system and to retrieve the down-hole unit. Because of their lightweight, convenient transportation and installation, high penetration rates and low power consumption, core auger drills are widely used for shallow drilling in ice. Nowadays at least 14 types of auger electromechani- cal drills were designed and tested in different foreign and national glaciological laboratories. However, auger options were usually determined by experience, and the main parameters （ helix angle of the fights and rotational speed） are varied in a wide range from drill to drill. If parameters of auger are not chosen properly, poorly en- gineered drills had troubles with low efficiency of cuttings transportation, jam of ice cuttings, repeated fragmen- tation, cutters icing and stop penetration, abnormal power consumption, high rotation torques, and so on. Thus, this paper presents the method of optimization of iee cuttings transportation of cable-suspended core auger drill on the base of the theory of rotary auger. As the result, the optimal helix angle was determined correspond- ing to the rotational speed from the transportation efficiency point of view.
文摘The article describes the possibilities of application of simulation modeling for the analysis of infrastructure and technology of transport services of enterprises. The main technological and possible economic effects for the enterprises arising at performance of modeling of a transport component of their work are resulted.
基金financial support from the Natural Science Foundation of China (grant numbers: 51661135021, 21606039, 91233201, and 21276044)
文摘In recent years the photovoltaic community has witnessed the unprecedented development of perovskite solar cells（PSCs） as they have taken the lead in emergent photovoltaic technologies. The power conversion efficiency of this new class of solar cells has been increased to a point where they are beginning to compete with more established technologies. Although PSCs have evolved a variety of structures, the use of hole-transporting materials（HTMs） remains indispensable. Here, an overview of the various types of available HTMs is presented. This includes organic and inorganic HTMs and is presented alongside recent progress in associated aspects of PSCs, including device architectures and fabrication techniques to produce high-quality perovskite films. The structure, electrochemistry, and physical properties of a variety of HTMs are discussed, highlighting considerations for those designing new HTMs. Finally, an outlook is presented to provide more concrete direction for the development and optimization of HTMs for highefficiency PSCs.
基金the financial supports from the NSFC(51472274)the GDUPS(2016)+2 种基金the program of Guangzhou Science and Technology Project(201504010031)the NSF of Guangdong Province(S2013030013474)the Fundamental Research Funds for the Central Universities
文摘Nanostructured TiO2 with differentiate morphologies has attracted tremendous attention due to its wide band-gap nature as well as outstanding optical and electric properties for solar-driven light-toelectricity conversion application. Layered-stacking TiO2 film such as double-layer, tri-layer, quadrupleor quintuplicate-layer, is highly desirable to the design of high-performance semiconductor material photoanodes and the development of advanced photovoltaic devices. In this minireview, we will summarize the recent progress and achievements on proof-of-concept of layered-stacking TiO2 films（LTFs） for solar cells with emphasis on the tailored properties and synergistic functionalization of LTFs, such as optimized sensitizer adsorption, broadened light confinement as well as facilitated electron transport characteristics.Various demonstrations of LTFs photovoltaic systems provide lots of possibilities and flexibilities for more efficient solar energy utilization that a wide variety of TiO2 with distinguished morphologies can be integrated into differently structured photoanodes with synergistic and complementary advantages. This key structure engineering technology will also pave the way for the development of next generation state-ofthe-art electronics and optoelectronics. Finally, from our point of view, we conclude the future research interest and efforts for constructing more efficient LTFs as photoelectrode, which will be highly warranted to advance the solar energy conversion process.
基金supported by National Natural Science Foundation of China(No.50637010)
文摘Based on the transmission line code TLCODE, a 1D circuit model for a transmission- line impedance transformer was developed and the simulation results were compared with those in the literature. The model was used to quantify the efficiencies of voltage-transport, energy- transport and power-transport for a transmission-line impedance transformer as functions of ψ （the ratio of the output impedance to the input impedance of the transformer） and Г （the ratio of the pulse width to the one-way transit time of the transformer） under a large scale of m （the coefficient of the generalized exponential impedance profile）. Simulation results suggest that with the increase in Г, from 0 to ∞, the power transport efficiency first increases and then decreases. The maximum power transport efficiency can reach 90% or even higher for an exponential impedance profile （m = 1）. With a consideration of dissipative loss in the dielectric and electrodes of the transformer, two representative designs of the water-insulated transformer are investigated for the next generation of petawatt-class z-pinch drivers. It is found that the dissipative losses in the electrodes are negligibly small, below 0.1%, but the dissipative loss in the water dielectric is about 1% to 4%.
基金supported by the National Nature Science Foundation of China (NO.21206110)Tianjin Science and Technology Support Plan Key Projects (NO.13ZCZDGX00900)
文摘Titanylphthalocyanine （TiOPc） as hole transporting material （HTM） was successfully synthesized by a simple process with low cost. Perovskite solar cells using the TiOPc as HTM were fabricated and characterized. TiOPc as HTM plays an important role in increasing the power conversion efficiency （PCE） by minimizing recombi- nation losses at the perovskite/Au interface because TiOPc as HTM can extract photogenerated holes from the perovskite and then transport quickly these charges to the back metal electrode. In the research, the β-TiOPc gives a higher PCE than α-TiOPc for the devices due to sufficient transfer dynamics, The β-TiOPc was applied in perovskite solar cells without clopping to afford an impressive PCE of 5.05% under AM 1.5G illumination at the thickness of 40 nm which is competitive with spiro-OMeTAD at the same condition. The present work suggests a guideline for optimizing the photovoltaic properties ofperovskite solar cells using the TiOPc as the HTM.
基金financial support from the 973 program(No.2014CB643503)the National Natural Science Foundation of China(No.21474088)+2 种基金financial support from NSFC(No.21674093)the National 1000 Young Talents Program hosted by China100 Talents Program by Zhejiang University
文摘In this review, we highlight the recent development of organic π-functional materials as buffer layers in constructing efficient perovskite solar cells（PVSCs）. By following a brief introduction on the PVSC development, device architecture and material design features, we exemplified the exciting progresses made in field by exploiting organic π-functional materials based hole and electron transport layers（HTLs and ETLs） to enable high-performance PVSCs.
基金supported by National Natural Science Foundation of China (No. 51329301)
文摘In this study, we report narrow-size distribution Zn_2SnO_4（ZSO） nanoparticles, which are produced by low-temperature solution-processed used as the electron extraction layer（EEL） in the inverted polymer solar cells（i-PSCs）. Moreover, poly[（9,9-bis（30-（N,N-dimethylamino）propyl）-2,7-fluorene）-alt-2,7-（9,9-dioctylfluorene）]（PFN） is used to modify the surface properties of ZSO thin film. By using the ZSO NPs/PFN as the EEL, the i-PSCs fabricated by poly[4,8-bis（2-ethylhexyloxyl）benzo[1,2-b：4,5-b0] dithio-phene-2,6-diyl-altethylhexyl-3-fluorothithieno [3,4-b]thiophene-2-carboxylate-4,6-diyl]（PTB7） blended with（6,6）-phenyl-C_（71）-butyric acid methylester（PC_（71）BM） bulk heterojunction（BHJ） composite, exhibits a power conversion efficiency（PCE） of 8.44%, which is nearly 10% enhancement as compared with that of7.75% observed from the i-PSCs by PTB7：PC_（71）BM BHJ composite using the ZnO/PFN EEL. The enhanced PCE is originated from improved interfacial contact between the EEL with BHJ active layer and good energy level alignment between BHJ active layer and the EEL. Our results indicate that we provide a simple way to boost efficiency of i-PSCs.
基金supported by the National Key R&D Program of China(grant no.2021YFB3800300)the National Natural Science Foundation of China(grant nos.22179143,22309201,and 22309202)the Jiangsu Funding Program for Excellent Postdoctoral Talent,and the Gusu Leading Talents Program(grant no.ZXL2023190).
文摘Solid-state batteries(SSBs)are considered as the next-generation battery technology,poised to deliver both high energy and enhanced safety.Nonetheless,their transition from laboratory to market is impeded by several critical challenges.Among these,the solid–solid interfaces within SSBs represent a bottleneck,characterized by issues such as poor physical contact,side reactions,temporal separation,and sluggish charge carrier transfer.Developing key materials to construct the efficient solid–solid interface is critical for building high-performance SSBs.Organic mixed ionic–electronic conductors(OMIECs)have emerged as a promising alternative to conventional conductors in addressing the abovementioned issues owing to their intrinsic properties,including the capability of conducting both ions and electrons,mechanical flexibility,and structural designability.This review will first elucidate the necessity of the integration of OMIECs in SSBs.Next,a comprehensive exploration of the composition,preparation methods,key advantages,and basic characterizations of OMIECs is presented.This review then delves into recent research progress on OMIECs in SSBs,with a special focus on their application in cathode coating layers,the creation of a 3D mixed conductive framework for Li hosting,and their integration as inner layers in Li anodes.Conclusively,potential future applications and innovative designs of OMIECs are discussed.
基金supported by the National Natural Science Foundation of China(No.22405248)the Joint Fund of Science and Technology R&D Plan of Henan Province(No.232301420003).
文摘The rational design of a heterostructural photocatalysts with efficient charge separation and accelerated interfacial charge transfer holds great promise for boosting photocatalytic activity.Herein,we have developed a unique hierarchical In_(4/3)P_(2)S_(6)/TiO_(2) heterojunction with P-O interfacial bonding for photocatalytic water reduction.By integrating emerging In_(4/3)P_(2)S_(6) nanosheets through intense interfacial coupling effect,the optimized In_(4/3)P_(2)S_(6)/TiO_(2) heterostructure exhibits a remarkably enhanced photocatalytic H2 evolution activity compared to that of pristine TiO_(2).Combined experimental and theoretical results confirm that multiple interfacial bonded step-scheme(S-scheme)charge transfer pathways are established in the In_(4/3)P_(2)S_(6)/TiO_(2) photocatalyst,which synergistically promote charge separation and transfer through the robust interfacial electric field and rapid charge migration pathways formed by interfacial bonds.This study emphasizes the significance of developing novel interfacial bonded In_(4/3)P_(2)S_(6)-based S-scheme heterostructures,paving a new strategy towards enhancing photocatalytic activity for H_(2) evolution.
文摘A concise definition of Transport Efficiency (TE) was given to examine the amount of transported grains in the pipe flow with certain energy consumption. The transport characteristics and the so-called 'roto-floating' characteristics were studied from the tests of sediment transport in the normal pipe flow and the spiral pipe flow, and hereby the energy gradients of the two kinds of pipe flows were obtained. By comparing the mean concentrations at the same gradient, it was concluded that the TE of the latter is several times to over ten times higher than that of the former, and the lift of the latter is 200 times larger than that of the former for the nearly same TE. The spiral flow in circular pipe is suitable for transporting fine grains of high concentration, and with sedimentation trend and coarse grains.
文摘Research interest in pneumatic conveying technologies in processes such as peanut harvesting and shelling has grown rapidly in recent years.However,the use of pneumatic conveyors in this application suffers from high pod damage rates and duct obstruction.To address these issues,we analyzed the critical speed of pneumatic transport for conveying the peanut pods and measured the angle of friction and coefficient of restitution of peanut pods on a variety of material surfaces.Based on the results of these tests,optimizations and improvements were made to the separator bowl,air supply duct,and conveying duct.A pneumatic conveying experiment was then performed using peanut pods.In the factorial experiment,it was found that increases in fan speed increase the pod damage rate and transport efficiency,while increases in the thickness of the cushioning/anti-obstruction layer decrease the rate of pod damage and transport efficiency.Pod damage rates were significantly affected by fan speed,the thickness of the cushioning/obstruction prevention layer,and interaction between these factors,while transport efficiency was only significantly affected by fan speed.It is proved by the machine verification test,the optimal parameters for the pneumatic transport of Baisha peanut pods with a moisture content of 7.24%was a fan speed of 2700 r/min and a cushioning/anti-obstruction layer thickness of 6 mm.A pod damage rate of 5.19%and transport efficiency of 92.03%were achieved using these parameters,which are sufficient for meeting the requirements of industrial applications.
基金Supported by NSFC(10475096)Special Fund for Equipment of CAS(U-37)
文摘The Beijing intense slow positron beam facility is based on the 1.3 GeV linac of Beijing ElectronPositron Collider （BEPC） aiming to produce mono-energetic intense slow positron beam for material science investigation. The plugged-in 22Na based slow positron beam section has been newly constructed to supply continuous beam time for the debugging of positron annihilation measurement stations and improve the Beijing intense slow positron beam time using efficiency. Performance testing result of the plugged-in 22Na based slow positron beam facility are reviewed in this paper, with the measurement of the beam transport efficiency, the view of beam spot, the adjustment of beam position, the measurement of beam intensity and energy spread etc. included.
