Panel data of rape input and output in 14 rape production provinces of China during 2006- 2013 were measured by data envelopment analysis(DEA). According to the measurement results,average scores of technology efficie...Panel data of rape input and output in 14 rape production provinces of China during 2006- 2013 were measured by data envelopment analysis(DEA). According to the measurement results,average scores of technology efficiency in Henan,Hunan,Jiangsu,Sichuan,Zhejiang and Chongqing were all 1,while average scores of Anhui,Qinghai,Yunnan,Gansu and Shaanxi were lower,which ranked latter in the 14 provinces. To further study the reason for lower pure technology efficiency in the 5 provinces,relaxation amount and relaxation degree of factor input in the year when its pure technology efficiency was not 1 were collected,thereby obtaining surplus situation of factor input in rape production of the 5 provinces. Moreover,the phenomenon that redundancy degree of farm manure surpassed that of chemical fertilizer,and material cost per mu was excess largely in the 5 provinces was explained,and some suggestions were proposed.展开更多
This research analyzes the effects of various environmental regulatory strategies on ecological technology diffusion efficiency(ETDE)across 30 Chinese provinces.It explores the roles of market type(MER),command contro...This research analyzes the effects of various environmental regulatory strategies on ecological technology diffusion efficiency(ETDE)across 30 Chinese provinces.It explores the roles of market type(MER),command control type(CER),and environmental protection type(EER)environmental regulations,alongside the moderating influences of industrial agglomeration(Agg),low-carbon pilot policy(Lcp),fiscal decentralization(FD),and official corruption(Cor)on ETDE.Results show that EER positively affects ETDE,whereas MER and CER tend to inhibit its improvement.The study underscores the complex interplay between these regulations and the significant impact of Agg and Lcp in enhancing ER's effectiveness.Additionally,it highlights the critical mediating roles of FD and Cor,suggesting that the quality of government operations profoundly influences the success of environmental regulations in promoting ecological technology diffusion.These findings emphasize the necessity for tailored environmental regulation strategies that take into account regional economic,population,and digital economy differences,to effectively foster ecological technology diffusion and support China's green development goals.The study also proposes actionable insights for policymakers.展开更多
Objective To provide new ideas for the effective treatment of many serious diseases and to solve many major medical problems faced by mankind.Methods In this paper,the invention patents in the field of stem cells in C...Objective To provide new ideas for the effective treatment of many serious diseases and to solve many major medical problems faced by mankind.Methods In this paper,the invention patents in the field of stem cells in China from 2010 to 2020 were taken as the research object,and the technology status quo in the field of stem cells was analyzed to predict the future development direction through quantitative analysis method.Results and Conclusion The development of stem cell technology in China is in a period of growth with great potential.Therefore,it is necessary to strengthen the ability of Chinese universities to combine production,education and research.Nowadays,the hotspots in stem cell technology are using culture medium to improve cell proliferation ability,production efficiency,and to induce differentiated cells.Meanwhile,the production efficiency of embryonic stem cells should be improved,and the immunomodulatory effect of embryonic stem cells can be exerted to screen drugs.Besides,the function of hematopoietic stem cells should be enhanced and apply mesenchymal cells in therapy.Since the potential technological gaps are the improvement of therapy,induced differentiation and efficiency of pluripotent stem cells,the improvement of progenitor cell proliferation and the control of cost,we should strengthen R&D investment in culture medium,embryonic stem cells and other technical fields,and achieve the purpose of reducing R&D costs and improving R&D efficiency.展开更多
This paper first constructed a system to evaluate the innovation efficiency of industrial companies within China's Mainland.Then,a principal component analysis(PCA) was performed to these indicators for dimensiona...This paper first constructed a system to evaluate the innovation efficiency of industrial companies within China's Mainland.Then,a principal component analysis(PCA) was performed to these indicators for dimensionality reduction,so as to figure out the technology innovation efficiency in these two phases,respectively.Finally,the overall efficiency of industrial companies in different regions was estimated and factorized via data envelopment analysis(DEA).The results showed that:(1)the efficiency of green technology innovation of industrial companies in China was relatively low as a whole,which mainly resulted from pure technical efficiency(PTE).Further,this huge gap continues to expand in these regions.And both PTE and scale efficiency(SE) in central and western regions leave much to be expected.(2)In the first phase of green technology development,when environmental factors were concerned,the efficiency was much lower than that without environmental considerations.Besides,the central and western regions were facing increasingly severe environmental problems,and there was a wide disparity in technology development efficiency among eastern,central,and western regions.(3)In the second phase of green technology commercialization,there were still more rooms for improvement in raising the efficiency of green technology innovation,and the efficiency in eastern,central,and western regions was ranked from highest to lowest.(4)Liaoning,Hebei,Heilongjiang,Xinjiang,Shanxi,Inner Mongolia,Yunnan,and Qinghai should focus on improving their technology;Jilin,Jiangxi,Anhui,and Guangxi should make their efforts to reduce resource redundancy;whereas Ningxia and Gansu should try to solve the above two issues.展开更多
Vigorously popularizing agricultural high-efficiency water-saving irrigation technology is a comprehensive implementation of the new water control thinking of "water saving priority, spatial balance, systematic g...Vigorously popularizing agricultural high-efficiency water-saving irrigation technology is a comprehensive implementation of the new water control thinking of "water saving priority, spatial balance, systematic governance, and two-handed effort" proposed by General Secretary Xi Jinping, and also an effective way to promote the sustainable use of water resources, increase agricultural production, increase farmers' income, and make rural areas rich. This paper analyzes the deficiencies in the process of popularizing high-efficiency water-saving irrigation technology in Beijing suburbs, and puts forward some countermeasures and suggestions, such as speeding up the comprehensive reform of agricultural water price, strengthening the publicity and training of high-efficiency water-saving irrigation technology, and improving the relevant policy support of Pro agriculture and benefiting agriculture.展开更多
With the appearance of novel radar signal with low intercept probability, the bandwidth of radar receiver is wider and wider. Wideband digital receiver becomes a research hotspot in the field of communication...With the appearance of novel radar signal with low intercept probability, the bandwidth of radar receiver is wider and wider. Wideband digital receiver becomes a research hotspot in the field of communication, radar and electronic reconnaissance, etc. As one of wideband digital receiver systems, digital channelized receiver has become a research emphasis due to the characteristics of full probability receiving and processing multiple signals. Digital channelized technology and signal sampling theory are deeply studied and an efficient channelized model is derived based on filter banks. The correctness of the model is verified by computer simulation The model has less computation compared with the traditional model, which is suitable for engineering application展开更多
Using the DEA analysis method,on the basis of the national panel data from 2002 to 2014,this paper made a comparative analysis on the rice production performance before and after the implementation of direct grain sub...Using the DEA analysis method,on the basis of the national panel data from 2002 to 2014,this paper made a comparative analysis on the rice production performance before and after the implementation of direct grain subsidy policy,and made an empirical analysis on the relationship between the direct grain subsidy policy and the changes in the rice production performance. The results showed that the effect of the direct grain subsidy policy on promoting the rice production performance is declining year by year,largely because drop of scale efficiency. Besides,there are problems of serious redundancy in agricultural subsidy,unreasonable resource allocation,leading to low performance and resource waste of rice production.展开更多
Based on the non-radial super-efficiency SBM model,the technical efficiency of forestry production in 30 provinces(municipalities,autonomous regions)across the country was measured from 2004 to 2018,and the Makov chai...Based on the non-radial super-efficiency SBM model,the technical efficiency of forestry production in 30 provinces(municipalities,autonomous regions)across the country was measured from 2004 to 2018,and the Makov chain was introduced to analyze the evolution trend.The research found that:The average PTE of China's forestry from 2004 to 2018 was 0.516,and the overall level was not high;regional imbalances were prominent,showing a distribution pattern of"high in the south and low in the north"and"high in the east and low in the west".Regions with low and high levels of Forestry PTE have certain characteristics of"path dependence".in the long run,Forestry PTE growth will face greater pressure.展开更多
To understand the resource features and geology in the deep Jinchuan nickel deposit, difficult geological conditions were systematically analyzed, including high stress, fragmentized ore rock, prevalent deformation, d...To understand the resource features and geology in the deep Jinchuan nickel deposit, difficult geological conditions were systematically analyzed, including high stress, fragmentized ore rock, prevalent deformation, difficult tunnel support, complicated rock mechanics, and low mining recovery. An integrated technology package was built for safe, efficient, and continuous mining in a deep, massive, and complex nickel and cobalt mine. This was done by the invention of a large-area continuous mining method with honeycomb drives; the establishment of ground control theory and a technology package for high-stress and fragmented ore rock： and the development of a new type of backfilling cement material, along with a deep backfilling technology that comprises the pipeline transport of high-density slurry with coarse aggregates. In this way, good solutions to existing problems were found to permit the efficient exploitation and comprehensive utilization of the resources in the deep Jinchuan nickel mine. In addition, a technological demonstration in an underground mine was performed using the cemented undercut-and-fill mining method for stressful, frag- mented, and rheological rock.展开更多
The general objective of this present work is to refine biogas in order to use it in an engine to produce electricity. The specific objective is focused on the availability and creation of energy, environmental protec...The general objective of this present work is to refine biogas in order to use it in an engine to produce electricity. The specific objective is focused on the availability and creation of energy, environmental protection, and the provision of biofertilizers to name a few. We worked on industrial applications and data for two years. The calculation methods and the most important parameters measured and observed during the work with various types of equations and monitoring, such as the search for the useful volume of the digester, the retention time, the organic load rate, the daily production of biogas, and the technological yield were made. The biogas produced was refined following the standards and purification procedure and the presence of H2S brought back to a ppm lower than 200. To better characterize our biogas, a weekly, monthly and annual monitoring was done. The aim of this monitoring was to understand the production curve and bring technological elements of positive change by working on the pH, the temperature, the ratio and inhibitors. Thus, at the beginning, at 25˚C and 1 atm, the 6 gas molecules had a volume of 146.61 liters, so for 1 g of COD consumed, there was 0.7636 L of gas with 50% CH4 and 50% CO2. We therefore sought to make this result higher with a biogas rate of 60% CH4 and 40% CO2. It is observed that the values can vary by ±10% (sometimes more) depending on the implementation conditions.展开更多
This paper attempts to explore the temporal and spatial nature of the marginal revenue of land, total factor productivity （TFP） change and its three components： technical change （TC）, technical efficiency change ...This paper attempts to explore the temporal and spatial nature of the marginal revenue of land, total factor productivity （TFP） change and its three components： technical change （TC）, technical efficiency change （TEC） and scale efficiency change （SEC） as seen in Chinese agricultural production from 1995 to 1999. Based on county-level data, the study utilized both stochastic frontier and mapping analyses methods. The results show that growth in the marginal revenue of land was diverse across various regions, where most gain occurred in eastern coastal zone, while loss was in Northwest and North China. China has experienced moderate decreases in annual TFP change （–0.26%） with considerable regional variations. Specifically, the administrative intervention in grain production and the deterioration of the agricultural technology diffusion system led to a moderate drop in annual TFP change. County-level mapping analyses took into account interregional variances in TFP and its components. Regarding components of TFP, TEC differences explain the majority of regional dispersions in TFP. As developed areas in China, the Huang-Huai-Hai region and the Beijing-Tianjin-Tangshan economic zone face the challenges of land conversion and grain security amidst the process of urbanization.展开更多
The purpose of this research is to design and develop a demonstration Set of a water cooling system using a Peltier with solar energy and technology,and IoT(Internet of Things),and test and measure the performance of ...The purpose of this research is to design and develop a demonstration Set of a water cooling system using a Peltier with solar energy and technology,and IoT(Internet of Things),and test and measure the performance of the Peltier Plate Water Cooling System Demonstration Set under different environmental conditions.To be used as a model for clean energy systems and experimental learning materials.The prototype system consists of a 100-W solar panel,a 12 V 20 Ah battery,a Peltier plate,a DS18B20 sensor,and a NodeMCU microcontroller.The system performance is determined by analyzing the energy drawn from the water(Q)compared to the electrical energy supplied to the plate(Q2)and calculating the coefficient of performance(COP)value to evaluate the performance of the system,as well as testing the operation under different light conditions(morning,noon,evening)with real-time temperature data and control behavior recorded via IoT(Internet of Things).The results showed that the system can reduce the water temperature by an average of 4°C-7.5°C within 60-90 min,with an average COP(COEFFICIENT OF PERFORMANCE)in the range of 0.3-0.4 during unstable solar energy periods.The system can respond to commands via the Blynk application in under 2 s and can also operate continuously on battery backup power during low-light hours.展开更多
In this study,the relationship between environmental regulations and technological innovation efficiencyis empirically examined via panel data from 33 iron and steel enterprises(ISs)in China between 2015 and 2021.The ...In this study,the relationship between environmental regulations and technological innovation efficiencyis empirically examined via panel data from 33 iron and steel enterprises(ISs)in China between 2015 and 2021.The results show that the average“innovation compensation effect”of environmental regulations on the technological innovation efficiency of ISs exceeds the average“compliance cost effect”,thus resulting in a clearly positivenet effect.Both the two-sided effects and the net effects vary across different years,geographical regions,andtypes of property rights.As the quantile of technological innovation efficiency increases,the positive influence ofenvironmental regulations tends to increase.Furthermore,the strengthening of financing constraints and firmcompetitiveness enhances the positive impact of environmental regulations on the technological innovation efficiency of ISs.Additionally,a double-threshold effect of environmental regulations on the technological innovationefficiency of ISs is revealed in this study.The realisation of the Porter hypothesis occurs when financing constraintsand firm competitiveness fall within specific threshold intervals.This research not only deepens our understandingof the relationship between environmental regulations and the technological innovation efficiency of ISs but alsoprovides valuable policy insights for optimising environmental regulations to facilitate targeted improvements in thelevel of technological innovation efficiency.展开更多
In recent years,the advancement of efficient and sustainable energy technologies has become a global priority,with particular focus on hydrogen production through water electrolysis[1].Proton exchange membrane water e...In recent years,the advancement of efficient and sustainable energy technologies has become a global priority,with particular focus on hydrogen production through water electrolysis[1].Proton exchange membrane water electrolysis(PEM-WE)technology has gained significant attention due to its ability to effectively couple with renewable power sources,offering high hydrogen production rates,high purity,and excellent scalability[2].However,the oxygen evolution reaction(OER),as a key reaction in the water electrolysis process,remains a bottleneck due to its slow kinetics,low efficiency,and high energy consumption[3].Particularly under acidic conditions,the stability in harsh oxidation environments makes OER reliant on expensive and scarce iridium-based catalysts[4,5].RuO_(2) has been considered as one of the potential alternative materials due to its low cost and high activity.However,its poor intrinsic stability limits its long-term application under practical conditions[6].Therefore,the search for efficient and stable acidic OER electrocatalysts has become a core issue for improving PEM-WE system performance.展开更多
Carbon nanotube field effect transistor（CNFET） shows lower threshold voltage and smaller leakage current in comparison to its CMOS counterpart. In this paper, two kinds of CNFET-based rectifiers, full-wave rectifier...Carbon nanotube field effect transistor（CNFET） shows lower threshold voltage and smaller leakage current in comparison to its CMOS counterpart. In this paper, two kinds of CNFET-based rectifiers, full-wave rectifiers and voltage doubler rectifiers are presented for biomedical implantable applications. Based on the standard 32 nm CNFET model, the electrical performance of CNFET rectifiers is analyzed and compared. Simulation results show the voltage conversion efficiency（VCE） and power conversion efficiency（PCE） achieve 70.82% and 72.49% for CNFET full-wave rectifiers and 56.60% and 61.17% for CNFET voltage double rectifiers at typical 1.0 V input voltage excitation, which are higher than that of CMOS design. Moreover, considering the controllable property of CNFET threshold voltage, the effect of various design parameters on the electrical performance is investigated.It is observed that the VCE and PCE of CNFET rectifier increase with increasing CNT diameter and number of tubes. The proposed results would provide some guidelines for design and optimization of CNFET-based rectifier circuits.展开更多
文摘Panel data of rape input and output in 14 rape production provinces of China during 2006- 2013 were measured by data envelopment analysis(DEA). According to the measurement results,average scores of technology efficiency in Henan,Hunan,Jiangsu,Sichuan,Zhejiang and Chongqing were all 1,while average scores of Anhui,Qinghai,Yunnan,Gansu and Shaanxi were lower,which ranked latter in the 14 provinces. To further study the reason for lower pure technology efficiency in the 5 provinces,relaxation amount and relaxation degree of factor input in the year when its pure technology efficiency was not 1 were collected,thereby obtaining surplus situation of factor input in rape production of the 5 provinces. Moreover,the phenomenon that redundancy degree of farm manure surpassed that of chemical fertilizer,and material cost per mu was excess largely in the 5 provinces was explained,and some suggestions were proposed.
基金supported by the Yunnan University Research Foundation Program(Grant No.KC-23233830).
文摘This research analyzes the effects of various environmental regulatory strategies on ecological technology diffusion efficiency(ETDE)across 30 Chinese provinces.It explores the roles of market type(MER),command control type(CER),and environmental protection type(EER)environmental regulations,alongside the moderating influences of industrial agglomeration(Agg),low-carbon pilot policy(Lcp),fiscal decentralization(FD),and official corruption(Cor)on ETDE.Results show that EER positively affects ETDE,whereas MER and CER tend to inhibit its improvement.The study underscores the complex interplay between these regulations and the significant impact of Agg and Lcp in enhancing ER's effectiveness.Additionally,it highlights the critical mediating roles of FD and Cor,suggesting that the quality of government operations profoundly influences the success of environmental regulations in promoting ecological technology diffusion.These findings emphasize the necessity for tailored environmental regulation strategies that take into account regional economic,population,and digital economy differences,to effectively foster ecological technology diffusion and support China's green development goals.The study also proposes actionable insights for policymakers.
文摘Objective To provide new ideas for the effective treatment of many serious diseases and to solve many major medical problems faced by mankind.Methods In this paper,the invention patents in the field of stem cells in China from 2010 to 2020 were taken as the research object,and the technology status quo in the field of stem cells was analyzed to predict the future development direction through quantitative analysis method.Results and Conclusion The development of stem cell technology in China is in a period of growth with great potential.Therefore,it is necessary to strengthen the ability of Chinese universities to combine production,education and research.Nowadays,the hotspots in stem cell technology are using culture medium to improve cell proliferation ability,production efficiency,and to induce differentiated cells.Meanwhile,the production efficiency of embryonic stem cells should be improved,and the immunomodulatory effect of embryonic stem cells can be exerted to screen drugs.Besides,the function of hematopoietic stem cells should be enhanced and apply mesenchymal cells in therapy.Since the potential technological gaps are the improvement of therapy,induced differentiation and efficiency of pluripotent stem cells,the improvement of progenitor cell proliferation and the control of cost,we should strengthen R&D investment in culture medium,embryonic stem cells and other technical fields,and achieve the purpose of reducing R&D costs and improving R&D efficiency.
基金supported by the Humanities and Social Science project of Ministry of Education of China[Grant Number:16YJA790036]the National Natural Science Foundation of China[Grant Number:71503272]
文摘This paper first constructed a system to evaluate the innovation efficiency of industrial companies within China's Mainland.Then,a principal component analysis(PCA) was performed to these indicators for dimensionality reduction,so as to figure out the technology innovation efficiency in these two phases,respectively.Finally,the overall efficiency of industrial companies in different regions was estimated and factorized via data envelopment analysis(DEA).The results showed that:(1)the efficiency of green technology innovation of industrial companies in China was relatively low as a whole,which mainly resulted from pure technical efficiency(PTE).Further,this huge gap continues to expand in these regions.And both PTE and scale efficiency(SE) in central and western regions leave much to be expected.(2)In the first phase of green technology development,when environmental factors were concerned,the efficiency was much lower than that without environmental considerations.Besides,the central and western regions were facing increasingly severe environmental problems,and there was a wide disparity in technology development efficiency among eastern,central,and western regions.(3)In the second phase of green technology commercialization,there were still more rooms for improvement in raising the efficiency of green technology innovation,and the efficiency in eastern,central,and western regions was ranked from highest to lowest.(4)Liaoning,Hebei,Heilongjiang,Xinjiang,Shanxi,Inner Mongolia,Yunnan,and Qinghai should focus on improving their technology;Jilin,Jiangxi,Anhui,and Guangxi should make their efforts to reduce resource redundancy;whereas Ningxia and Gansu should try to solve the above two issues.
文摘Vigorously popularizing agricultural high-efficiency water-saving irrigation technology is a comprehensive implementation of the new water control thinking of "water saving priority, spatial balance, systematic governance, and two-handed effort" proposed by General Secretary Xi Jinping, and also an effective way to promote the sustainable use of water resources, increase agricultural production, increase farmers' income, and make rural areas rich. This paper analyzes the deficiencies in the process of popularizing high-efficiency water-saving irrigation technology in Beijing suburbs, and puts forward some countermeasures and suggestions, such as speeding up the comprehensive reform of agricultural water price, strengthening the publicity and training of high-efficiency water-saving irrigation technology, and improving the relevant policy support of Pro agriculture and benefiting agriculture.
基金Natural Science Foundation of Inner Mongolia Autonomous Region of China(No.2013MS0916)Research Program of Science and Technology at Universities of Inner Mongolia Autonomous Region(No.NJZY237)
文摘With the appearance of novel radar signal with low intercept probability, the bandwidth of radar receiver is wider and wider. Wideband digital receiver becomes a research hotspot in the field of communication, radar and electronic reconnaissance, etc. As one of wideband digital receiver systems, digital channelized receiver has become a research emphasis due to the characteristics of full probability receiving and processing multiple signals. Digital channelized technology and signal sampling theory are deeply studied and an efficient channelized model is derived based on filter banks. The correctness of the model is verified by computer simulation The model has less computation compared with the traditional model, which is suitable for engineering application
文摘Using the DEA analysis method,on the basis of the national panel data from 2002 to 2014,this paper made a comparative analysis on the rice production performance before and after the implementation of direct grain subsidy policy,and made an empirical analysis on the relationship between the direct grain subsidy policy and the changes in the rice production performance. The results showed that the effect of the direct grain subsidy policy on promoting the rice production performance is declining year by year,largely because drop of scale efficiency. Besides,there are problems of serious redundancy in agricultural subsidy,unreasonable resource allocation,leading to low performance and resource waste of rice production.
文摘Based on the non-radial super-efficiency SBM model,the technical efficiency of forestry production in 30 provinces(municipalities,autonomous regions)across the country was measured from 2004 to 2018,and the Makov chain was introduced to analyze the evolution trend.The research found that:The average PTE of China's forestry from 2004 to 2018 was 0.516,and the overall level was not high;regional imbalances were prominent,showing a distribution pattern of"high in the south and low in the north"and"high in the east and low in the west".Regions with low and high levels of Forestry PTE have certain characteristics of"path dependence".in the long run,Forestry PTE growth will face greater pressure.
文摘To understand the resource features and geology in the deep Jinchuan nickel deposit, difficult geological conditions were systematically analyzed, including high stress, fragmentized ore rock, prevalent deformation, difficult tunnel support, complicated rock mechanics, and low mining recovery. An integrated technology package was built for safe, efficient, and continuous mining in a deep, massive, and complex nickel and cobalt mine. This was done by the invention of a large-area continuous mining method with honeycomb drives; the establishment of ground control theory and a technology package for high-stress and fragmented ore rock： and the development of a new type of backfilling cement material, along with a deep backfilling technology that comprises the pipeline transport of high-density slurry with coarse aggregates. In this way, good solutions to existing problems were found to permit the efficient exploitation and comprehensive utilization of the resources in the deep Jinchuan nickel mine. In addition, a technological demonstration in an underground mine was performed using the cemented undercut-and-fill mining method for stressful, frag- mented, and rheological rock.
文摘The general objective of this present work is to refine biogas in order to use it in an engine to produce electricity. The specific objective is focused on the availability and creation of energy, environmental protection, and the provision of biofertilizers to name a few. We worked on industrial applications and data for two years. The calculation methods and the most important parameters measured and observed during the work with various types of equations and monitoring, such as the search for the useful volume of the digester, the retention time, the organic load rate, the daily production of biogas, and the technological yield were made. The biogas produced was refined following the standards and purification procedure and the presence of H2S brought back to a ppm lower than 200. To better characterize our biogas, a weekly, monthly and annual monitoring was done. The aim of this monitoring was to understand the production curve and bring technological elements of positive change by working on the pH, the temperature, the ratio and inhibitors. Thus, at the beginning, at 25˚C and 1 atm, the 6 gas molecules had a volume of 146.61 liters, so for 1 g of COD consumed, there was 0.7636 L of gas with 50% CH4 and 50% CO2. We therefore sought to make this result higher with a biogas rate of 60% CH4 and 40% CO2. It is observed that the values can vary by ±10% (sometimes more) depending on the implementation conditions.
基金National Basic Research Program of China （973 Program）,No.2010CB950904 National Key Technology R＆D Program of China,No.2008BAK50B06+2 种基金 No.2008BAC43B01 National Natural Science Foundation of China,No.40801231 No.41071343
文摘This paper attempts to explore the temporal and spatial nature of the marginal revenue of land, total factor productivity （TFP） change and its three components： technical change （TC）, technical efficiency change （TEC） and scale efficiency change （SEC） as seen in Chinese agricultural production from 1995 to 1999. Based on county-level data, the study utilized both stochastic frontier and mapping analyses methods. The results show that growth in the marginal revenue of land was diverse across various regions, where most gain occurred in eastern coastal zone, while loss was in Northwest and North China. China has experienced moderate decreases in annual TFP change （–0.26%） with considerable regional variations. Specifically, the administrative intervention in grain production and the deterioration of the agricultural technology diffusion system led to a moderate drop in annual TFP change. County-level mapping analyses took into account interregional variances in TFP and its components. Regarding components of TFP, TEC differences explain the majority of regional dispersions in TFP. As developed areas in China, the Huang-Huai-Hai region and the Beijing-Tianjin-Tangshan economic zone face the challenges of land conversion and grain security amidst the process of urbanization.
基金it was supported in kind through resources,technical consultation,and laboratory access generously provided by Chaiyapon Thongchaisuratkrul and relevant institutions.
文摘The purpose of this research is to design and develop a demonstration Set of a water cooling system using a Peltier with solar energy and technology,and IoT(Internet of Things),and test and measure the performance of the Peltier Plate Water Cooling System Demonstration Set under different environmental conditions.To be used as a model for clean energy systems and experimental learning materials.The prototype system consists of a 100-W solar panel,a 12 V 20 Ah battery,a Peltier plate,a DS18B20 sensor,and a NodeMCU microcontroller.The system performance is determined by analyzing the energy drawn from the water(Q)compared to the electrical energy supplied to the plate(Q2)and calculating the coefficient of performance(COP)value to evaluate the performance of the system,as well as testing the operation under different light conditions(morning,noon,evening)with real-time temperature data and control behavior recorded via IoT(Internet of Things).The results showed that the system can reduce the water temperature by an average of 4°C-7.5°C within 60-90 min,with an average COP(COEFFICIENT OF PERFORMANCE)in the range of 0.3-0.4 during unstable solar energy periods.The system can respond to commands via the Blynk application in under 2 s and can also operate continuously on battery backup power during low-light hours.
基金The National Natural Science Foundation of China(71871016)The Fundamental Research Funds for the Central Universities(FRF-DF-20-68)。
文摘In this study,the relationship between environmental regulations and technological innovation efficiencyis empirically examined via panel data from 33 iron and steel enterprises(ISs)in China between 2015 and 2021.The results show that the average“innovation compensation effect”of environmental regulations on the technological innovation efficiency of ISs exceeds the average“compliance cost effect”,thus resulting in a clearly positivenet effect.Both the two-sided effects and the net effects vary across different years,geographical regions,andtypes of property rights.As the quantile of technological innovation efficiency increases,the positive influence ofenvironmental regulations tends to increase.Furthermore,the strengthening of financing constraints and firmcompetitiveness enhances the positive impact of environmental regulations on the technological innovation efficiency of ISs.Additionally,a double-threshold effect of environmental regulations on the technological innovationefficiency of ISs is revealed in this study.The realisation of the Porter hypothesis occurs when financing constraintsand firm competitiveness fall within specific threshold intervals.This research not only deepens our understandingof the relationship between environmental regulations and the technological innovation efficiency of ISs but alsoprovides valuable policy insights for optimising environmental regulations to facilitate targeted improvements in thelevel of technological innovation efficiency.
文摘In recent years,the advancement of efficient and sustainable energy technologies has become a global priority,with particular focus on hydrogen production through water electrolysis[1].Proton exchange membrane water electrolysis(PEM-WE)technology has gained significant attention due to its ability to effectively couple with renewable power sources,offering high hydrogen production rates,high purity,and excellent scalability[2].However,the oxygen evolution reaction(OER),as a key reaction in the water electrolysis process,remains a bottleneck due to its slow kinetics,low efficiency,and high energy consumption[3].Particularly under acidic conditions,the stability in harsh oxidation environments makes OER reliant on expensive and scarce iridium-based catalysts[4,5].RuO_(2) has been considered as one of the potential alternative materials due to its low cost and high activity.However,its poor intrinsic stability limits its long-term application under practical conditions[6].Therefore,the search for efficient and stable acidic OER electrocatalysts has become a core issue for improving PEM-WE system performance.
基金Project supported by the National Natural Science Foundation of China(Nos.61131001,61404077,61571248)the Science and Technology Fund of Zhejiang Province(No.2015C31090)+2 种基金the Natural Science Foundation of Ningbo(No.2014A610147)State Key Laboratory of ASIC&System(No.2015KF006)the K.C.Wong Magna Fund in Ningbo University
文摘Carbon nanotube field effect transistor（CNFET） shows lower threshold voltage and smaller leakage current in comparison to its CMOS counterpart. In this paper, two kinds of CNFET-based rectifiers, full-wave rectifiers and voltage doubler rectifiers are presented for biomedical implantable applications. Based on the standard 32 nm CNFET model, the electrical performance of CNFET rectifiers is analyzed and compared. Simulation results show the voltage conversion efficiency（VCE） and power conversion efficiency（PCE） achieve 70.82% and 72.49% for CNFET full-wave rectifiers and 56.60% and 61.17% for CNFET voltage double rectifiers at typical 1.0 V input voltage excitation, which are higher than that of CMOS design. Moreover, considering the controllable property of CNFET threshold voltage, the effect of various design parameters on the electrical performance is investigated.It is observed that the VCE and PCE of CNFET rectifier increase with increasing CNT diameter and number of tubes. The proposed results would provide some guidelines for design and optimization of CNFET-based rectifier circuits.
