The hub-driven virtual rail train is a novel urban transportation system that amalgamates the benefits of modern trams and buses.However,this system is plagued by issues such as decreased ride comfort and severe defor...The hub-driven virtual rail train is a novel urban transportation system that amalgamates the benefits of modern trams and buses.However,this system is plagued by issues such as decreased ride comfort and severe deformation of urban roads due to the increase in sprung mass and long-term rolling at the same position.To address these concerns and improve the human-vehicle-road friendliness of the virtual rail train,we propose an Improved Sky-Ground Hook and Acceleration-Driven Damper control(Improved SH-GH-ADD control)strategy for the semi-active suspension system.This control monitors the vibration acceleration signal of the unsprung mass in real-time and selects the mixed Sky-Hook and Acceleration-Driven Damper(SH-ADD)control or the mixed Ground-Hook and Acceleration-Driven Damper(GH-ADD)control based on the positive and negative values of the vibration acceleration of the unsprung mass.The Improved SH-GH-ADD control combines the advantages of SH-ADD control and GH-ADD control to achieve control of the sprung mass and unsprung mass in the full fre-quency band.Finally,through simulation and comparative analysis with traditional SH-ADD,GH-ADD,and mixed SH-GH control,we demonstrate the exceptional performance of the proposed algorithm.展开更多
Goal of this research is to detect possible relations between animal-related attitudes and verbal aggressiveness as well as types combining such parameters. The sample collected in 2015 contains two adult education cl...Goal of this research is to detect possible relations between animal-related attitudes and verbal aggressiveness as well as types combining such parameters. The sample collected in 2015 contains two adult education classes equivalent to secondary school level (class A = 23 inmates and B = 12 inmates, all male) at a correctional facility. Questionnaires were used. Network analysis software (Visone) and conventional statistics (SPSS) are used for calculating network variables (indegree, outdegree, katz, pageranketc) and implementing Spearman test and Principal Component Analysis. Inmates who have adopted an animal-friendly value system and are too coward to react against torture of animals, maintain a repressed emotion. If they do not intervene and provoke, then they are also not targeted by others. No reaction against torture is also connected with a deep-rooted aggressiveness. Concerning superficial aggressiveness, a profile, whose characterize is multiple verbal aggressiveness, can be attributed to repressed emotions. A type is torturing and indifferently restricts his aggressiveness, as he can satisfy his need of dominance by being aggressive towards animals. A type of inmate who loves animals and reacts against their torture, presents the most restricted and relatively smooth aggressiveness, as he discharges his repressed emotions to this reaction. Under condition of indifference, keeping pets is not evidence of loving but of a need of companionship. As for the deep-rooted aggressiveness (over-extroversion), it does not seem to be triggered by any repression.展开更多
During the process of construction and maintenance, buildings have had many negativeeffects on the environment, such as destruction of the ecological environment, consumption of naturalresources, air pollution and gen...During the process of construction and maintenance, buildings have had many negativeeffects on the environment, such as destruction of the ecological environment, consumption of naturalresources, air pollution and generation of large amounts of construction waste. The development of greenbuildings has greatly improved the negative impact of buildings on the environment. In the whole life cycleof construction and maintenance of buildings, the consumption of natural resources is reduced, and thedamage to the environment is reduced. In this article, the representative green buildings in Asia are analyzedfrom the aspects of regional humanity, land saving measures, energy-saving measures, behavior-guidedgreen design strategies, building materials, effective greening measures and smart city strategies, and theexcellent design strategies are summarized, in order to provide reference for future architectural practice.展开更多
In connection with the current prospect of decarbonization of coal energy through the use of small nuclear power plants (SNPPs) at existing TPPs as heat sources for heat supply to municipal heating networks, there is ...In connection with the current prospect of decarbonization of coal energy through the use of small nuclear power plants (SNPPs) at existing TPPs as heat sources for heat supply to municipal heating networks, there is a technological need to improve heat supply schemes to increase their environmental friendliness and efficiency. The paper proves the feasibility of using the heat-feeding mode of ASHPs for urban heat supply by heating the network water with steam taken from the turbine. The ratio of electric and thermal power of a “nuclear” combined heat and power plant is given. The advantage of using a heat pump, which provides twice as much electrical power with the same heat output, is established. Taking into account that heat in these modes is supplied with different potential, the energy efficiency was used to compare these options. To increase the heat supply capacity, a scheme with the use of a high-pressure heater in the backpressure mode and with the heating of network water with hot steam was proposed. Heat supply from ASHPs is efficient and environmentally friendly even in the case of significant remoteness of heat consumers.展开更多
The security of digital images transmitted via the Internet or other public media is of the utmost importance.Image encryption is a method of keeping an image secure while it travels across a non-secure communication ...The security of digital images transmitted via the Internet or other public media is of the utmost importance.Image encryption is a method of keeping an image secure while it travels across a non-secure communication medium where it could be intercepted by unauthorized entities.This study provides an approach to color image encryption that could find practical use in various contexts.The proposed method,which combines four chaotic systems,employs singular value decomposition and a chaotic sequence,making it both secure and compression-friendly.The unified average change intensity,the number of pixels’change rate,information entropy analysis,correlation coefficient analysis,compression friendliness,and security against brute force,statistical analysis and differential attacks are all used to evaluate the algorithm’s performance.Following a thorough investigation of the experimental data,it is concluded that the proposed image encryption approach is secure against a wide range of attacks and provides superior compression friendliness when compared to chaos-based alternatives.展开更多
An environmental friendly anodizing treatment (Anomag) from a phosphate-based so lution without heavy metals on AZ91D magnesium alloy was studied. The characteri stics of the coatings, such as structure, composition a...An environmental friendly anodizing treatment (Anomag) from a phosphate-based so lution without heavy metals on AZ91D magnesium alloy was studied. The characteri stics of the coatings, such as structure, composition and corrosion resistance w ere investigated. The effects of this anodizing treatment on the mechanical prop erties were examined. X-ray diffraction (XRD) analysis revealed that the structu re of the coatings is amorphous or glassy. In salt spray tests coatings with an average thickness of 10μm had an anticorrosive performance of over 1000 hours. Fatigue tests revealed that anodizing onto AZ91D magnesium alloy does not affect the fatigue strength. These results demonstrate the utility of this anodizing t reatment on magnesium alloy for application as a structural material, such as in the automotive field.展开更多
In the study, a novel environmental soybean seed coating agent was made of natural polymer, trace elements, trace fertilizer and biopesticides etc., with the condition of high performance-to-price ratio and environmen...In the study, a novel environmental soybean seed coating agent was made of natural polymer, trace elements, trace fertilizer and biopesticides etc., with the condition of high performance-to-price ratio and environmental friendliness. Effects of this soybean seed coating agent on soybean yield were tested through the laboratory and farm experiments. The tested results showed that the soybean yield using this seed coating agent was increased by 15.46%, and its cost was decreased by 27.8%, compared with the conventional soybean seed coating agent. It’s nontoxic and harmless to human and animals, more friendly to the environment. So it has obvious economic and environmental benefits.展开更多
A sewage heat pump system and its application based on a project in Chongqing,China,were discussed. Based on the sewage conditions,a feasibility analysis of the sewage heat pump air conditioning system was conducted. ...A sewage heat pump system and its application based on a project in Chongqing,China,were discussed. Based on the sewage conditions,a feasibility analysis of the sewage heat pump air conditioning system was conducted. The theoretical and quantitative calculations indicate that sewage flux in the city sewage main pipe in the project can satisfy heat exchange requirements,and taking water from the pipes has relatively small influence on the pipe net in summer and winter. The sewage heat pump air-conditioning system can save 21.5% operating cost in one year,which is energy efficient and environmentally friendly.展开更多
The cyclo-N_(6)anion is a total nitrogen unit with higher nitrogen content than cyclo-N^(-)_(5).However,the low decomposition barrier of cyclo-N_(6)anions hinders its application as a high energy density material(HEDM...The cyclo-N_(6)anion is a total nitrogen unit with higher nitrogen content than cyclo-N^(-)_(5).However,the low decomposition barrier of cyclo-N_(6)anions hinders its application as a high energy density material(HEDM).Using first-principles calculations,we reveal that the covalent components that enhance the interaction between the cyclo-N_(6)anion and the cation can effectively improve the stability of cyclo-N_(6)anions.The actinide metals(Th,Pa,U)are selected as suitable cations.Further electronic structure analysis showed that the charge transfer from the actinide metal to cyclo-N_(6)anions resulted in a strong covalent bond,which promoted the stability of the cyclo-N_(6)anion in the Th(N_(6)),Pa(N_(6)),and U(N_(6))structure.This discovery is helpful for the rational design and synthesis of new HEDMs.展开更多
The traditional transport industry makes a lot of damage to the nature and consumes a large part of resources.In this paper,we study transportation system from the perspective of dynamic balance of ecological,economic...The traditional transport industry makes a lot of damage to the nature and consumes a large part of resources.In this paper,we study transportation system from the perspective of dynamic balance of ecological,economic and social benefits,and then put forward the theoretical framework of ecological transportation based on ecological responsibility which is mainly about resource-saving and environmentfriendly constraints,including the connotation,characteristics,driving factors and impact factors of ecological transportation.On this basis,this study applies the system dynamics to establish a dynamic model for the balance between transportation system and external environment including economic,policy,resource and environment.展开更多
Five studies were conducted in order to produce less waste and economize the application of a CdCl2–Na3C6H5O7– KOH–H3BO3/NaOH/KCl–(NH2)2CS definite aqueous system in the chemical bath deposition of CdS thin films,...Five studies were conducted in order to produce less waste and economize the application of a CdCl2–Na3C6H5O7– KOH–H3BO3/NaOH/KCl–(NH2)2CS definite aqueous system in the chemical bath deposition of CdS thin films, as well as to generate supporting information helpful to explain the effects of varying certain parameters established for the use of this formulation. These studies are related to the utility of the pH 10 borate buffer, to the selection of the appropriateOH–concentration, commercial alkali, and reaction temperature, and to the reusing of the residual solution. These studies were conducted by means of optical characterization, pH measurements, energy consumption tests, and chemical analysis;and all possible implications were analyzed in detail and widely supported by the literature. It is observed that the addition of 5.0 mL of pH 10 borate buffer in the reaction solutions only causes a slight reduction in the pH value and, therefore, in the thickness of the resulted films. It is observed that a decrease in CdCl2 concentration causes an increase in the pH values, and when such reagent concentration is varied it is necessary to determine the pH value at which the best CdS films can be obtained;this indicates the existence of an optimum pH of deposition, depending on the used reagent concentrations. It is demonstrated that the use of KOH and NaOH is interchangeable, and the advantages of NaOH are evaluated in the context of hygroscopicity, CO2 absorption, purity, and price. It is observed that the energy consumption when depositing a determined film is lower at high temperatures, and it is concluded that the time and energy savings at high temperatures are undoubtedly advantages in the deposition process of CdS thin films. A formulation to recycle the residual solution is presented, which is very important for the reducing of residual volume, and, therefore, in the minimizing of the environmental impact. An indirect objective of this work is to generate interest in identifying those points that could be modified in other chemical formulations to minimize costs and waste.展开更多
The efficient utilization of elemental sulfur(S8) for developing high value-added chemicals is a global concern considering its abundant sources and yearly accelerating environmental issues. However, it has been a lon...The efficient utilization of elemental sulfur(S8) for developing high value-added chemicals is a global concern considering its abundant sources and yearly accelerating environmental issues. However, it has been a long-standing challenge to directly transform elemental sulfur to sulfur-containing polymer, especially via an environmentally benign manner. Herein, a unique chemo-differentiating multicomponent polymerization(MCP) of elemental sulfur, chloroform, and diamine is reported to construct polythiourea based on amine-involved two sequential reactions including isothiocyanation and nucleophilic addition.This strategy features isocynide-free monomers as starting materials, mild conditions, high molecular weights(up to72,900 g/mol) and desired yields(up to 83%). With the advantages of inactive isocyanation and active nucleophilic addition, the stoichiometric balance of amine and isothiocyanate could be delicately controlled to afford various polythioureas with high molecular weights. The polythioureas have been further utilized in the Cu-based aqueous catalysis and Hg-based ion adsorption.展开更多
There is a great demand for high performance rapid repair mortar(RRM)because of the wide use of cement concrete.Solid-waste-based sulfoaluminate cement(WSAC)is very suitable as a green cementitious material for repair...There is a great demand for high performance rapid repair mortar(RRM)because of the wide use of cement concrete.Solid-waste-based sulfoaluminate cement(WSAC)is very suitable as a green cementitious material for repair materials because of its characteristics of high early-age strength and short setting time.However,the influence and optimization of various factors of WSAC-based RRM,such as water-to-RRM ratio,binder-to-sand ratio and additives,as well as the further solid waste replacement of aggregate,remain to be studied.This paper comprehensively studied the influence of the above factors on the performance of WSAC-based RRM and obtained a green high-performance RRM by optimizing these factors.The experimental results showed that the early and late strength of the obtained RRM is excellent,and the setting time and fluidity are appropriate,which reflected good mechanical properties and construction performance.Ordinary Portland cement(OPC)doping could not improve RRM strength.It was feasible to prepare RRM with gold tailing sand replacing part of the quartz sand.This paper provides data and a theoretical basis for the preparation of high-performance RRM based on solid waste,expanding the high value utilization of solid waste,which is conducive to the development of a low carbon society.展开更多
The increasing applications of net-zero energy buildings (NZEBs) will lead to more frequent and larger energy interactions with the connected power grid, thereby being able to result in severe grid overvoltage risks. ...The increasing applications of net-zero energy buildings (NZEBs) will lead to more frequent and larger energy interactions with the connected power grid, thereby being able to result in severe grid overvoltage risks. Control optimization has been proven effective to reduce such risks. Existing controls have oversimplified the overvoltage quantification by simply using the aggregated power exchanges to represent the connected grid overvoltages. Ignoring the complex voltage influences among the grid nodes, such oversimplification can easily result in low-accuracy impact evaluations of the NZEB-grid energy interactions, thereby causing non-optimal/unsatisfying overvoltage mitigations. Therefore, this study proposes a novel coordinated control method in which a power-distribution-network model has been adopted for more accurate overvoltage quantification. Meanwhile, the battery operations of individual NZEBs are iteratively coordinated using a sequential optimization approach for achieving the global optimum with substantially reduced computation complexity. For verifications, the proposed coordinated control has been systematically compared with an uncoordinated control and a conventional coordinated control in grid overvoltage minimization. The study results show that the overvoltage improvements can reach 23.5% and 12.3% compared with the uncoordinated control and the conventional coordinated control, respectively. The reasons behind the improvements have also been analyzed in detail. The proposed coordinated control can be used in practice to improve NZEB-clusters’ grid friendliness.展开更多
基金This research was funded by Natural Science Foundation of Sichuan Province(2023NSFSC0395)the Sichuan Science and Technology Program(2022ZH CG0061)the SWJTU Science and Technology Innovation Project(2682022CX008).
文摘The hub-driven virtual rail train is a novel urban transportation system that amalgamates the benefits of modern trams and buses.However,this system is plagued by issues such as decreased ride comfort and severe deformation of urban roads due to the increase in sprung mass and long-term rolling at the same position.To address these concerns and improve the human-vehicle-road friendliness of the virtual rail train,we propose an Improved Sky-Ground Hook and Acceleration-Driven Damper control(Improved SH-GH-ADD control)strategy for the semi-active suspension system.This control monitors the vibration acceleration signal of the unsprung mass in real-time and selects the mixed Sky-Hook and Acceleration-Driven Damper(SH-ADD)control or the mixed Ground-Hook and Acceleration-Driven Damper(GH-ADD)control based on the positive and negative values of the vibration acceleration of the unsprung mass.The Improved SH-GH-ADD control combines the advantages of SH-ADD control and GH-ADD control to achieve control of the sprung mass and unsprung mass in the full fre-quency band.Finally,through simulation and comparative analysis with traditional SH-ADD,GH-ADD,and mixed SH-GH control,we demonstrate the exceptional performance of the proposed algorithm.
文摘Goal of this research is to detect possible relations between animal-related attitudes and verbal aggressiveness as well as types combining such parameters. The sample collected in 2015 contains two adult education classes equivalent to secondary school level (class A = 23 inmates and B = 12 inmates, all male) at a correctional facility. Questionnaires were used. Network analysis software (Visone) and conventional statistics (SPSS) are used for calculating network variables (indegree, outdegree, katz, pageranketc) and implementing Spearman test and Principal Component Analysis. Inmates who have adopted an animal-friendly value system and are too coward to react against torture of animals, maintain a repressed emotion. If they do not intervene and provoke, then they are also not targeted by others. No reaction against torture is also connected with a deep-rooted aggressiveness. Concerning superficial aggressiveness, a profile, whose characterize is multiple verbal aggressiveness, can be attributed to repressed emotions. A type is torturing and indifferently restricts his aggressiveness, as he can satisfy his need of dominance by being aggressive towards animals. A type of inmate who loves animals and reacts against their torture, presents the most restricted and relatively smooth aggressiveness, as he discharges his repressed emotions to this reaction. Under condition of indifference, keeping pets is not evidence of loving but of a need of companionship. As for the deep-rooted aggressiveness (over-extroversion), it does not seem to be triggered by any repression.
基金Sponsored by Interdisciplinary Research Projects of the Fundamental Research Funds for the Central Universities(DUT19JC55)High-level Talents Innovation Support Project of Dalian City(2017RQ076).
文摘During the process of construction and maintenance, buildings have had many negativeeffects on the environment, such as destruction of the ecological environment, consumption of naturalresources, air pollution and generation of large amounts of construction waste. The development of greenbuildings has greatly improved the negative impact of buildings on the environment. In the whole life cycleof construction and maintenance of buildings, the consumption of natural resources is reduced, and thedamage to the environment is reduced. In this article, the representative green buildings in Asia are analyzedfrom the aspects of regional humanity, land saving measures, energy-saving measures, behavior-guidedgreen design strategies, building materials, effective greening measures and smart city strategies, and theexcellent design strategies are summarized, in order to provide reference for future architectural practice.
文摘In connection with the current prospect of decarbonization of coal energy through the use of small nuclear power plants (SNPPs) at existing TPPs as heat sources for heat supply to municipal heating networks, there is a technological need to improve heat supply schemes to increase their environmental friendliness and efficiency. The paper proves the feasibility of using the heat-feeding mode of ASHPs for urban heat supply by heating the network water with steam taken from the turbine. The ratio of electric and thermal power of a “nuclear” combined heat and power plant is given. The advantage of using a heat pump, which provides twice as much electrical power with the same heat output, is established. Taking into account that heat in these modes is supplied with different potential, the energy efficiency was used to compare these options. To increase the heat supply capacity, a scheme with the use of a high-pressure heater in the backpressure mode and with the heating of network water with hot steam was proposed. Heat supply from ASHPs is efficient and environmentally friendly even in the case of significant remoteness of heat consumers.
基金funded by Deanship of Scientific Research at King Khalid University under Grant Number R.G.P.2/86/43.
文摘The security of digital images transmitted via the Internet or other public media is of the utmost importance.Image encryption is a method of keeping an image secure while it travels across a non-secure communication medium where it could be intercepted by unauthorized entities.This study provides an approach to color image encryption that could find practical use in various contexts.The proposed method,which combines four chaotic systems,employs singular value decomposition and a chaotic sequence,making it both secure and compression-friendly.The unified average change intensity,the number of pixels’change rate,information entropy analysis,correlation coefficient analysis,compression friendliness,and security against brute force,statistical analysis and differential attacks are all used to evaluate the algorithm’s performance.Following a thorough investigation of the experimental data,it is concluded that the proposed image encryption approach is secure against a wide range of attacks and provides superior compression friendliness when compared to chaos-based alternatives.
文摘An environmental friendly anodizing treatment (Anomag) from a phosphate-based so lution without heavy metals on AZ91D magnesium alloy was studied. The characteri stics of the coatings, such as structure, composition and corrosion resistance w ere investigated. The effects of this anodizing treatment on the mechanical prop erties were examined. X-ray diffraction (XRD) analysis revealed that the structu re of the coatings is amorphous or glassy. In salt spray tests coatings with an average thickness of 10μm had an anticorrosive performance of over 1000 hours. Fatigue tests revealed that anodizing onto AZ91D magnesium alloy does not affect the fatigue strength. These results demonstrate the utility of this anodizing t reatment on magnesium alloy for application as a structural material, such as in the automotive field.
文摘In the study, a novel environmental soybean seed coating agent was made of natural polymer, trace elements, trace fertilizer and biopesticides etc., with the condition of high performance-to-price ratio and environmental friendliness. Effects of this soybean seed coating agent on soybean yield were tested through the laboratory and farm experiments. The tested results showed that the soybean yield using this seed coating agent was increased by 15.46%, and its cost was decreased by 27.8%, compared with the conventional soybean seed coating agent. It’s nontoxic and harmless to human and animals, more friendly to the environment. So it has obvious economic and environmental benefits.
基金Project(50838009) supported by the National Natural Science Foundation of ChinaProjects(2006BAJ02A09+1 种基金2006BAJ02A13-4) supported by the National Key Technologies R&D ProgramProject(2006BAJ01A06-3) supported by the Key R & D Program during the Eleventh Five-Year Plan Period,China
文摘A sewage heat pump system and its application based on a project in Chongqing,China,were discussed. Based on the sewage conditions,a feasibility analysis of the sewage heat pump air conditioning system was conducted. The theoretical and quantitative calculations indicate that sewage flux in the city sewage main pipe in the project can satisfy heat exchange requirements,and taking water from the pipes has relatively small influence on the pipe net in summer and winter. The sewage heat pump air-conditioning system can save 21.5% operating cost in one year,which is energy efficient and environmentally friendly.
基金National Natural Science Foundation of China(No.11805157)Sichuan Provincial Department of Science and Technology Application Fundamental Research,China(No.2017JY0146)+1 种基金China West Normal University Scientific Research Innovation Team Project(No.CXTD2016-2)China West Normal University Talent Research Fund Project(No.CXTD2017-10)。
文摘The cyclo-N_(6)anion is a total nitrogen unit with higher nitrogen content than cyclo-N^(-)_(5).However,the low decomposition barrier of cyclo-N_(6)anions hinders its application as a high energy density material(HEDM).Using first-principles calculations,we reveal that the covalent components that enhance the interaction between the cyclo-N_(6)anion and the cation can effectively improve the stability of cyclo-N_(6)anions.The actinide metals(Th,Pa,U)are selected as suitable cations.Further electronic structure analysis showed that the charge transfer from the actinide metal to cyclo-N_(6)anions resulted in a strong covalent bond,which promoted the stability of the cyclo-N_(6)anion in the Th(N_(6)),Pa(N_(6)),and U(N_(6))structure.This discovery is helpful for the rational design and synthesis of new HEDMs.
基金supported by the National Social Science Fund of China(Grant No.15BJY069)Shanghai University Knowledge Service Platform(Grant No.ZF1209)
文摘The traditional transport industry makes a lot of damage to the nature and consumes a large part of resources.In this paper,we study transportation system from the perspective of dynamic balance of ecological,economic and social benefits,and then put forward the theoretical framework of ecological transportation based on ecological responsibility which is mainly about resource-saving and environmentfriendly constraints,including the connotation,characteristics,driving factors and impact factors of ecological transportation.On this basis,this study applies the system dynamics to establish a dynamic model for the balance between transportation system and external environment including economic,policy,resource and environment.
文摘Five studies were conducted in order to produce less waste and economize the application of a CdCl2–Na3C6H5O7– KOH–H3BO3/NaOH/KCl–(NH2)2CS definite aqueous system in the chemical bath deposition of CdS thin films, as well as to generate supporting information helpful to explain the effects of varying certain parameters established for the use of this formulation. These studies are related to the utility of the pH 10 borate buffer, to the selection of the appropriateOH–concentration, commercial alkali, and reaction temperature, and to the reusing of the residual solution. These studies were conducted by means of optical characterization, pH measurements, energy consumption tests, and chemical analysis;and all possible implications were analyzed in detail and widely supported by the literature. It is observed that the addition of 5.0 mL of pH 10 borate buffer in the reaction solutions only causes a slight reduction in the pH value and, therefore, in the thickness of the resulted films. It is observed that a decrease in CdCl2 concentration causes an increase in the pH values, and when such reagent concentration is varied it is necessary to determine the pH value at which the best CdS films can be obtained;this indicates the existence of an optimum pH of deposition, depending on the used reagent concentrations. It is demonstrated that the use of KOH and NaOH is interchangeable, and the advantages of NaOH are evaluated in the context of hygroscopicity, CO2 absorption, purity, and price. It is observed that the energy consumption when depositing a determined film is lower at high temperatures, and it is concluded that the time and energy savings at high temperatures are undoubtedly advantages in the deposition process of CdS thin films. A formulation to recycle the residual solution is presented, which is very important for the reducing of residual volume, and, therefore, in the minimizing of the environmental impact. An indirect objective of this work is to generate interest in identifying those points that could be modified in other chemical formulations to minimize costs and waste.
基金supported by the National Natural Science Foundation of China(21978039)the Natural Science Foundation of Jiangsu Province(BK20221265,BK20211100)the Fundamental Research Funds for the Central Universities(DUT21YG133,DUT22YG224).
文摘The efficient utilization of elemental sulfur(S8) for developing high value-added chemicals is a global concern considering its abundant sources and yearly accelerating environmental issues. However, it has been a long-standing challenge to directly transform elemental sulfur to sulfur-containing polymer, especially via an environmentally benign manner. Herein, a unique chemo-differentiating multicomponent polymerization(MCP) of elemental sulfur, chloroform, and diamine is reported to construct polythiourea based on amine-involved two sequential reactions including isothiocyanation and nucleophilic addition.This strategy features isocynide-free monomers as starting materials, mild conditions, high molecular weights(up to72,900 g/mol) and desired yields(up to 83%). With the advantages of inactive isocyanation and active nucleophilic addition, the stoichiometric balance of amine and isothiocyanate could be delicately controlled to afford various polythioureas with high molecular weights. The polythioureas have been further utilized in the Cu-based aqueous catalysis and Hg-based ion adsorption.
基金National Key R&D Program of China(No.2020YFC1910000)the Shandong Natural Science Foundation Youth Project(No.ZR2020QE201).
文摘There is a great demand for high performance rapid repair mortar(RRM)because of the wide use of cement concrete.Solid-waste-based sulfoaluminate cement(WSAC)is very suitable as a green cementitious material for repair materials because of its characteristics of high early-age strength and short setting time.However,the influence and optimization of various factors of WSAC-based RRM,such as water-to-RRM ratio,binder-to-sand ratio and additives,as well as the further solid waste replacement of aggregate,remain to be studied.This paper comprehensively studied the influence of the above factors on the performance of WSAC-based RRM and obtained a green high-performance RRM by optimizing these factors.The experimental results showed that the early and late strength of the obtained RRM is excellent,and the setting time and fluidity are appropriate,which reflected good mechanical properties and construction performance.Ordinary Portland cement(OPC)doping could not improve RRM strength.It was feasible to prepare RRM with gold tailing sand replacing part of the quartz sand.This paper provides data and a theoretical basis for the preparation of high-performance RRM based on solid waste,expanding the high value utilization of solid waste,which is conducive to the development of a low carbon society.
文摘The increasing applications of net-zero energy buildings (NZEBs) will lead to more frequent and larger energy interactions with the connected power grid, thereby being able to result in severe grid overvoltage risks. Control optimization has been proven effective to reduce such risks. Existing controls have oversimplified the overvoltage quantification by simply using the aggregated power exchanges to represent the connected grid overvoltages. Ignoring the complex voltage influences among the grid nodes, such oversimplification can easily result in low-accuracy impact evaluations of the NZEB-grid energy interactions, thereby causing non-optimal/unsatisfying overvoltage mitigations. Therefore, this study proposes a novel coordinated control method in which a power-distribution-network model has been adopted for more accurate overvoltage quantification. Meanwhile, the battery operations of individual NZEBs are iteratively coordinated using a sequential optimization approach for achieving the global optimum with substantially reduced computation complexity. For verifications, the proposed coordinated control has been systematically compared with an uncoordinated control and a conventional coordinated control in grid overvoltage minimization. The study results show that the overvoltage improvements can reach 23.5% and 12.3% compared with the uncoordinated control and the conventional coordinated control, respectively. The reasons behind the improvements have also been analyzed in detail. The proposed coordinated control can be used in practice to improve NZEB-clusters’ grid friendliness.