Due to the existence of dual-role factors,it is difficult to evaluate the production efficiency of two-stage systems.Unlike single-stage systems,two-stage systems involve intermediate products that serve as both input...Due to the existence of dual-role factors,it is difficult to evaluate the production efficiency of two-stage systems.Unlike single-stage systems,two-stage systems involve intermediate products that serve as both inputs and outputs.Hence,to overcome existing obstacles,we propose a novel approach called the two-stage enhanced Russell model with dual-role factors(T-ERM-D)to assess the overall efficiency of two-stage production systems.Furthermore,divisional models are developed to evaluate the efficiency of each individual stage.The 0-1 programming is applied to deal with dual-role factors.To handle the non-linearity of these models,the Charnes-Cooper transformation is employed to convert them into linear ones.Using the proposed models,we evaluate efficiency scores of 10 supply chains involving suppliers and producers.By comparing the results obtained from new models with those obtained from models that do not consider dual-role factors,we validate the advantages of the proposed approach.展开更多
Lithium-sulfur batteries(LSBs)are promising as the next generation energy storage options.However,their wide applications have been technically challenged by the diffusion losses of polysulfides and polysulfide shuttl...Lithium-sulfur batteries(LSBs)are promising as the next generation energy storage options.However,their wide applications have been technically challenged by the diffusion losses of polysulfides and polysulfide shuttle effect.In this work,the small organic molecules of 2,5-dichloropyrazine(2,5-DCP)were combined with Co-doped carbon(CoA NAC)flakes to achieve the synergic effect of the covalent and chemical sulfur fixation,so as that the immobilization-conversion of polysulfides in LSBs was greatly enhanced.More specifically,the nucleophilic substitution of the 2,5-DCP additive in the electrolyte with polysulfides formed the CAS bonds.Through the further covalent N-Li bonds between the N atoms in 2,5-DCP and polysulfides,sulfur fixation was achieved in the form of solid organosulfur.Meanwhile,the CoA NAC flakes served as the sulfur cathode to chemically anchor the polysulfides.The interaction mechanism between CoA NAC/2,5-DCP and polysulfides was explored by the density functional theory(DFT)calculations and in-situ infrared spectroscopy.The results showed that the optimal“with 2,5-DCP”sample-assembled LSB exhibited an initial discharge specific capacity of 1244 mA h g^(-1)at 0.2C,and a capacity decay rate of 0.053%per cycle was displayed after 800 cycles at 1C.The good cycling stability with a high sulfur-loaded electrode sample suggested that the synergic effect of covalent/chemical sulfur fixation enabled the enhancement of polysulfides immobilization-conversion in LSBs.展开更多
Hydrogen storage and delivery technology is still a bottleneck in the hydrogen industry chain.Among all kinds of hydrogen storage methods,light-weight solid-state hydrogen storage(LSHS)materials could become promising...Hydrogen storage and delivery technology is still a bottleneck in the hydrogen industry chain.Among all kinds of hydrogen storage methods,light-weight solid-state hydrogen storage(LSHS)materials could become promising due to its intrinsic high hydrogen capacity.Hydrolysis reaction of LSHS materials occurs at moderate conditions,indicating the potential for portable applications.At present,most of review work focuses on the improvement of material performance,especially the catalysts design.This part is important,but the others,such as operation modes,are also vital to to make full use of material potential in the practical applications.Different operation modes of hydrolysis reaction have an impact on hydrogen capacity to various degrees.For example,hydrolysis in solution would decrease the hydrogen capacity of hydrogen generator to a low value due to the excessive water participating in the reaction.Therefore,application-oriented operation modes could become a key problem for hydrolysis reaction of LSHS materials.In this paper,the operation modes of hydrolysis reaction and their practical applications are mainly reviewed.The implements of each operation mode are discussed and compared in detail to determine the suitable one for practical applications with the requirement of high energy density.The current challenges and future directions are also discussed.展开更多
Based on the rapid simulation of Markov Chain on samples in failure region,a novel method of reliability analysis combiningMonte Carlo Markov Chain(MCMC)with random forest algorithmwas proposed.Firstly,a series of sam...Based on the rapid simulation of Markov Chain on samples in failure region,a novel method of reliability analysis combiningMonte Carlo Markov Chain(MCMC)with random forest algorithmwas proposed.Firstly,a series of samples distributing around limit state function are generated by MCMC.Then,the samples were taken as training data to establish the random forest model.Afterwards,Monte Carlo simulation was used to evaluate the failure probability.Finally,examples demonstrate the proposed method possesses higher computational efficiency and accuracy.展开更多
In order to understand the variation of FPV strains in the Jinan area, Shandong Province, China, the VP2 gene of 6 FPV strains was sequenced, and the analysis of the genetic relationship, evolution and main functional...In order to understand the variation of FPV strains in the Jinan area, Shandong Province, China, the VP2 gene of 6 FPV strains was sequenced, and the analysis of the genetic relationship, evolution and main functional site variation was carried out. It was found that FPV-XY2, FPV-XY3 and FPV-XY6 were the same strain with 100% homology, and also close to FPV-XY1, and the homology between FPV-XY4 and FPV-XY5 was close. The homology between the reference strain and the test strain was over 99.3%. According to the evolutionary analysis, the genetic relationship among FPV-XY1, FPV-XY2, FPV-XY3, FPV-XY6 was close, and the genetic relationship between FPV-XY4 and FPV-XY5 was close, and the result was similar to the homologous result. Compared with the VP2 amino acid sequence of the standard strain FPV-CU4, the VP2 protein of all the test strains changed from I to t on the 101st Amino acid, this may be the cause of immune failure in these 6 cases;the change of a to s in the 91st amino acid position of FPV-XY1, FPV-XY2, FPV-XY3, FPV-XY6 may be the cause of enhanced virulence of FPV. This study provides a reference for exploring the epidemic law of FP in the Jinan area, the standard of FP treatment plan and the research and development of FPV subunit vaccine.展开更多
The imperative to address traditional energy crises and environmental concerns has accelerated the need for energy structure transformation.However,the variable nature of renewable energy poses challenges in meeting c...The imperative to address traditional energy crises and environmental concerns has accelerated the need for energy structure transformation.However,the variable nature of renewable energy poses challenges in meeting complex practical energy requirements.To address this issue,the construction of a multifunctional large-scale stationary energy storage system is considered an effective solution.This paper critically examines the battery and hydrogen hybrid energy storage systems.Both technologies face limitations hindering them from fully meeting future energy storage needs,such as large storage capacity in limited space,frequent storage with rapid response,and continuous storage without loss.Batteries,with their rapid response(<1 s)and high efficiency(>90%),excel in frequent short-duration energy storage.However,limitations such as a self-discharge rate(>1%)and capacity loss(~20%)restrict their use for long-duration energy storage.Hydrogen,as a potential energy carrier,is suitable for large-scale,long-duration energy storage due to its high energy density,steady state,and low loss.Nevertheless,it is less efficient for frequent energy storage due to its low storage efficiency(~50%).Ongoing research suggests that a battery and hydrogen hybrid energy storage system could combine the strengths of both technologies to meet the growing demand for large-scale,long-duration energy storage.To assess their applied potentials,this paper provides a detailed analysis of the research status of both energy storage technologies using proposed key performance indices.Additionally,application-oriented future directions and challenges of the battery and hydrogen hybrid energy storage system are outlined from multiple perspectives,offering guidance for the development of advanced energy storage systems.展开更多
The bind-free carbon cloth-supported electrodes hold the promises for high-performance electrochemical capacitors with high specific capacitance and good cyclic stability.Considering the close connection between their...The bind-free carbon cloth-supported electrodes hold the promises for high-performance electrochemical capacitors with high specific capacitance and good cyclic stability.Considering the close connection between their performance and the amount of carbon material loaded on the electrodes,in this work,NiCo_(2)O_(4) nanowires were firstly grown on the substrate of active carbon cloth to provide the necessary surface area in the longitudinal direction.Then,the quinone-rich nitrogen-doped carbon shell structure was formed around NiCo_(2)O_(4) nanowires,and the obtained composite was used as electrode for electric double layer capacitor.The results showed that the composite electrode displayed an area-specific capacitance of 1794 mF·cm^(-2) at the current density of 1 mA·cm^(-2).The assembled symmetric electric double layer capacitor achieved a high energy density of 6.55 mW·h·cm^(-3) at a power density of 180 mW·cm^(-3).The assembled symmetric capacitor exhibited a capacitance retention of 88.96%after 10000 charge/discharge cycles at the current density of 20 mA·cm^(-2).These results indicated the potentials in the preparation of the carbon electrode materials with high energy density and good cycling stability.展开更多
DEA(data envelopment analysis) models can be divided into two groups: Radial DEA and non-radial DEA, and the latter has higher discriminatory power than the former. The range adjusted measure(RAM) is an effective and ...DEA(data envelopment analysis) models can be divided into two groups: Radial DEA and non-radial DEA, and the latter has higher discriminatory power than the former. The range adjusted measure(RAM) is an effective and widely used non-radial DEA approach. However, to the best of our knowledge, there is no literature on the integer-valued super-efficiency RAM-DEA model,especially when undesirable outputs are included. We first propose an integer-valued RAM-DEA mode with undesirable outputs and then extend this model to an integer-valued super-efficiency RAM-DEA model with undesirable outputs. Compared with other DEA models, the two novel models have many advantages: 1) They are non-oriented and non-radial DEA models, which enable decision makers to simultaneously and non-proportionally improve inputs and outputs;2) They can handle integer-valued variables and undesirable outputs, so the results obtained are more reliable;3) The results can be easily obtained as it is based on linear programming;4) The integer-valued super-efficiency RAM-DEA model with undesirable outputs can be used to accurately rank efficient DMUs. The proposed models are applied to evaluate the efficiency of China’s regional transportation systems(RTSs) considering the number of transport accidents(an undesirable output). The results help decision makers improve the performance of inefficient RTSs and analyze the strengths of efficient RTSs.展开更多
基金Supported by the National Natural Science Foundation of China(72262024)the Program for Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region(NJYT22095)。
文摘Due to the existence of dual-role factors,it is difficult to evaluate the production efficiency of two-stage systems.Unlike single-stage systems,two-stage systems involve intermediate products that serve as both inputs and outputs.Hence,to overcome existing obstacles,we propose a novel approach called the two-stage enhanced Russell model with dual-role factors(T-ERM-D)to assess the overall efficiency of two-stage production systems.Furthermore,divisional models are developed to evaluate the efficiency of each individual stage.The 0-1 programming is applied to deal with dual-role factors.To handle the non-linearity of these models,the Charnes-Cooper transformation is employed to convert them into linear ones.Using the proposed models,we evaluate efficiency scores of 10 supply chains involving suppliers and producers.By comparing the results obtained from new models with those obtained from models that do not consider dual-role factors,we validate the advantages of the proposed approach.
基金the financially supports from the National Natural Science Foundation of China(51963004)the Natural Science Foundation of Shandong Province of China(ZR2020MB024)。
文摘Lithium-sulfur batteries(LSBs)are promising as the next generation energy storage options.However,their wide applications have been technically challenged by the diffusion losses of polysulfides and polysulfide shuttle effect.In this work,the small organic molecules of 2,5-dichloropyrazine(2,5-DCP)were combined with Co-doped carbon(CoA NAC)flakes to achieve the synergic effect of the covalent and chemical sulfur fixation,so as that the immobilization-conversion of polysulfides in LSBs was greatly enhanced.More specifically,the nucleophilic substitution of the 2,5-DCP additive in the electrolyte with polysulfides formed the CAS bonds.Through the further covalent N-Li bonds between the N atoms in 2,5-DCP and polysulfides,sulfur fixation was achieved in the form of solid organosulfur.Meanwhile,the CoA NAC flakes served as the sulfur cathode to chemically anchor the polysulfides.The interaction mechanism between CoA NAC/2,5-DCP and polysulfides was explored by the density functional theory(DFT)calculations and in-situ infrared spectroscopy.The results showed that the optimal“with 2,5-DCP”sample-assembled LSB exhibited an initial discharge specific capacity of 1244 mA h g^(-1)at 0.2C,and a capacity decay rate of 0.053%per cycle was displayed after 800 cycles at 1C.The good cycling stability with a high sulfur-loaded electrode sample suggested that the synergic effect of covalent/chemical sulfur fixation enabled the enhancement of polysulfides immobilization-conversion in LSBs.
基金financially supported by the National Key R&D Program of China(2022YFE0101300)the National Natural Science Foundation of China(52176203 and 52050027)the China Education Association for International Exchange(202006)。
文摘Hydrogen storage and delivery technology is still a bottleneck in the hydrogen industry chain.Among all kinds of hydrogen storage methods,light-weight solid-state hydrogen storage(LSHS)materials could become promising due to its intrinsic high hydrogen capacity.Hydrolysis reaction of LSHS materials occurs at moderate conditions,indicating the potential for portable applications.At present,most of review work focuses on the improvement of material performance,especially the catalysts design.This part is important,but the others,such as operation modes,are also vital to to make full use of material potential in the practical applications.Different operation modes of hydrolysis reaction have an impact on hydrogen capacity to various degrees.For example,hydrolysis in solution would decrease the hydrogen capacity of hydrogen generator to a low value due to the excessive water participating in the reaction.Therefore,application-oriented operation modes could become a key problem for hydrolysis reaction of LSHS materials.In this paper,the operation modes of hydrolysis reaction and their practical applications are mainly reviewed.The implements of each operation mode are discussed and compared in detail to determine the suitable one for practical applications with the requirement of high energy density.The current challenges and future directions are also discussed.
基金This study was supported by the Fundamental Research Funds for the Central Universities(Grant No.NS2020005)Natural Science Foundation of Jiangsu Province(Grant No.BK20190424)Natural Science Foundation of Shaanxi Province(Grant No.2019JQ-470).
文摘Based on the rapid simulation of Markov Chain on samples in failure region,a novel method of reliability analysis combiningMonte Carlo Markov Chain(MCMC)with random forest algorithmwas proposed.Firstly,a series of samples distributing around limit state function are generated by MCMC.Then,the samples were taken as training data to establish the random forest model.Afterwards,Monte Carlo simulation was used to evaluate the failure probability.Finally,examples demonstrate the proposed method possesses higher computational efficiency and accuracy.
文摘In order to understand the variation of FPV strains in the Jinan area, Shandong Province, China, the VP2 gene of 6 FPV strains was sequenced, and the analysis of the genetic relationship, evolution and main functional site variation was carried out. It was found that FPV-XY2, FPV-XY3 and FPV-XY6 were the same strain with 100% homology, and also close to FPV-XY1, and the homology between FPV-XY4 and FPV-XY5 was close. The homology between the reference strain and the test strain was over 99.3%. According to the evolutionary analysis, the genetic relationship among FPV-XY1, FPV-XY2, FPV-XY3, FPV-XY6 was close, and the genetic relationship between FPV-XY4 and FPV-XY5 was close, and the result was similar to the homologous result. Compared with the VP2 amino acid sequence of the standard strain FPV-CU4, the VP2 protein of all the test strains changed from I to t on the 101st Amino acid, this may be the cause of immune failure in these 6 cases;the change of a to s in the 91st amino acid position of FPV-XY1, FPV-XY2, FPV-XY3, FPV-XY6 may be the cause of enhanced virulence of FPV. This study provides a reference for exploring the epidemic law of FP in the Jinan area, the standard of FP treatment plan and the research and development of FPV subunit vaccine.
基金supported by the National Key R&D Program of China(2022YFE0101300)the National Natural Science Foundation of China(52176203)+1 种基金the Key R&D Project of Shaanxi Province,China(No.2023-GHZD-13)the“Young Talent Support Plan”of Xi'an Jiaotong University(No.QB-A-JZB2015004).
文摘The imperative to address traditional energy crises and environmental concerns has accelerated the need for energy structure transformation.However,the variable nature of renewable energy poses challenges in meeting complex practical energy requirements.To address this issue,the construction of a multifunctional large-scale stationary energy storage system is considered an effective solution.This paper critically examines the battery and hydrogen hybrid energy storage systems.Both technologies face limitations hindering them from fully meeting future energy storage needs,such as large storage capacity in limited space,frequent storage with rapid response,and continuous storage without loss.Batteries,with their rapid response(<1 s)and high efficiency(>90%),excel in frequent short-duration energy storage.However,limitations such as a self-discharge rate(>1%)and capacity loss(~20%)restrict their use for long-duration energy storage.Hydrogen,as a potential energy carrier,is suitable for large-scale,long-duration energy storage due to its high energy density,steady state,and low loss.Nevertheless,it is less efficient for frequent energy storage due to its low storage efficiency(~50%).Ongoing research suggests that a battery and hydrogen hybrid energy storage system could combine the strengths of both technologies to meet the growing demand for large-scale,long-duration energy storage.To assess their applied potentials,this paper provides a detailed analysis of the research status of both energy storage technologies using proposed key performance indices.Additionally,application-oriented future directions and challenges of the battery and hydrogen hybrid energy storage system are outlined from multiple perspectives,offering guidance for the development of advanced energy storage systems.
基金the Natural Science Foundation of Shandong Province of China (Grant No.ZR2020MB024)for financially supporting this work.
文摘The bind-free carbon cloth-supported electrodes hold the promises for high-performance electrochemical capacitors with high specific capacitance and good cyclic stability.Considering the close connection between their performance and the amount of carbon material loaded on the electrodes,in this work,NiCo_(2)O_(4) nanowires were firstly grown on the substrate of active carbon cloth to provide the necessary surface area in the longitudinal direction.Then,the quinone-rich nitrogen-doped carbon shell structure was formed around NiCo_(2)O_(4) nanowires,and the obtained composite was used as electrode for electric double layer capacitor.The results showed that the composite electrode displayed an area-specific capacitance of 1794 mF·cm^(-2) at the current density of 1 mA·cm^(-2).The assembled symmetric electric double layer capacitor achieved a high energy density of 6.55 mW·h·cm^(-3) at a power density of 180 mW·cm^(-3).The assembled symmetric capacitor exhibited a capacitance retention of 88.96%after 10000 charge/discharge cycles at the current density of 20 mA·cm^(-2).These results indicated the potentials in the preparation of the carbon electrode materials with high energy density and good cycling stability.
基金Supported by the National Natural Science Foundation of China(71862026)the China Postdoctoral Science Foundation(2018T110209)+2 种基金the Natural Science Foundation of Inner Mongolia(2018MS07006)the“13th Five Year”Plan of Educational Science Research in Inner Mongolia(NGJGH2018016)the State Scholarship Fund of China Scholarship Council(20180815502)。
文摘DEA(data envelopment analysis) models can be divided into two groups: Radial DEA and non-radial DEA, and the latter has higher discriminatory power than the former. The range adjusted measure(RAM) is an effective and widely used non-radial DEA approach. However, to the best of our knowledge, there is no literature on the integer-valued super-efficiency RAM-DEA model,especially when undesirable outputs are included. We first propose an integer-valued RAM-DEA mode with undesirable outputs and then extend this model to an integer-valued super-efficiency RAM-DEA model with undesirable outputs. Compared with other DEA models, the two novel models have many advantages: 1) They are non-oriented and non-radial DEA models, which enable decision makers to simultaneously and non-proportionally improve inputs and outputs;2) They can handle integer-valued variables and undesirable outputs, so the results obtained are more reliable;3) The results can be easily obtained as it is based on linear programming;4) The integer-valued super-efficiency RAM-DEA model with undesirable outputs can be used to accurately rank efficient DMUs. The proposed models are applied to evaluate the efficiency of China’s regional transportation systems(RTSs) considering the number of transport accidents(an undesirable output). The results help decision makers improve the performance of inefficient RTSs and analyze the strengths of efficient RTSs.
