Nowadays,the predominant source for approximately 90%of epoxy resin materials worldwide is the diglycidyl ether of bisphenol A(DGEBA).However,the increasing recognition of environmental concerns,such as global warming...Nowadays,the predominant source for approximately 90%of epoxy resin materials worldwide is the diglycidyl ether of bisphenol A(DGEBA).However,the increasing recognition of environmental concerns,such as global warming and the depletion of petroleum reserves,necessitates the exploration of alternative options,specifically bio-epoxy resin derived from sustainable resources.Nonetheless,the inadequate flame retardancy of bio-epoxy resin presents a notable drawback,limiting its applicability in high-risk environments.The objective of this review article is to provide a concise overview of the latest and upto-date advances in flame-retardant epoxy resins derived from sustainable sources.Firstly,the discussion encompasses inherently flame-retardant bio-based epoxy resins,considering both bio-based epoxy monomers and bio-based curing agents,focusing on their flame retardancy and mechanical properties.Furthermore,the utilization of phosphorus-containing and silicon-containing additives in bio-based epoxy is explored.Additionally,a comprehensive evaluation of partially bio-based intrinsically flame retardant epoxy resins is provided.Finally,this article offers an extensive survey of the current state-of-the-art in the field and presents future perspectives,serving as a valuable resource for researchers engaged in the study of flame-retardant epoxy resins derived from sustainable resources.展开更多
In recent years,bio-based polymeric materials have attracted increased attention owing to their distinctive prop-erties,including richness,sustainability,environmental friendliness,and biodegradability.This article re...In recent years,bio-based polymeric materials have attracted increased attention owing to their distinctive prop-erties,including richness,sustainability,environmental friendliness,and biodegradability.This article reviews the recent developments and potential trends of research on bio-based polymers synthesized from various re-newable resources.It covers the resources and structures of bio-based monomers,the methods of synthesis and properties of bio-based thermoplastics and thermosets,the production of bio-based composites and the fabrica-tion of functional bio-based polymers.Finally,the technological and future challenges related to enabling these materials to apply in the industry have been discussed,together with the potential solutions or directions.展开更多
In COVID-19 pandemic in the world, alcohol (ethanol) can be listed as a sterilizing disinfectant. It absolutely played a Messianic function on the sterilization effect. And it is said that it has one more function cal...In COVID-19 pandemic in the world, alcohol (ethanol) can be listed as a sterilizing disinfectant. It absolutely played a Messianic function on the sterilization effect. And it is said that it has one more function called “salinity reduction” but that function is not widely known. The two functions (Sterilization & Salinity Reduction) mentioned above are extremely important regarding the theme of “raw seawater into beverage” in this study. It is thought that if the two functions are achieved other water quality items such as NO<sup>-</sup>2</sub> and other items can be cleared with comparative ease. To put briefly the feature of modern waterworks in a word, it can be said that “source of water is river water and its sterilization is chlorine”. In this study, we set up it with a completely new sanitization method (great reset), that is, “source of water is mixtures (seawater and rainwater) and its sterilization is ethanol”. And it can be also expected that the capture and storage of ethanol as a renewable resource is basically possible by utilizing sunlight as a natural power. Therefore, we think that this resolves itself into a question of the choice (sense of value/culture) of the users. It means that how users finally balance out with three factors, i.e., cost, risk (safety) and benefit. Based on the viewpoint mentioned above, we examined the possibility of raw seawater into beverage using ethanol as a renewable resource to create humankind’s wisdom to the settlement (breakthrough) of the water scarcity in the world including Asia and Africa. As a result, we have obtained the new findings that suggest the possibility of raw seawater into beverage using ethanol as a renewable resource.展开更多
In order to achieve a highly accurate estimation of solar energy resource potential,a novel hybrid ensemble-learning approach,hybridizing Advanced Squirrel-Search Optimization Algorithm(ASSOA)and support vector regres...In order to achieve a highly accurate estimation of solar energy resource potential,a novel hybrid ensemble-learning approach,hybridizing Advanced Squirrel-Search Optimization Algorithm(ASSOA)and support vector regression,is utilized to estimate the hourly tilted solar irradiation for selected arid regions in Algeria.Long-term measured meteorological data,including mean-air temperature,relative humidity,wind speed,alongside global horizontal irradiation and extra-terrestrial horizontal irradiance,were obtained for the two cities of Tamanrasset-and-Adrar for two years.Five computational algorithms were considered and analyzed for the suitability of estimation.Further two new algorithms,namely Average Ensemble and Ensemble using support vector regression were developed using the hybridization approach.The accuracy of the developed models was analyzed in terms of five statistical error metrics,as well as theWilcoxon rank-sum and ANOVA test.Among the previously selected algorithms,K Neighbors Regressor and support vector regression exhibited good performances.However,the newly proposed ensemble algorithms exhibited even better performance.The proposed model showed relative root mean square errors lower than 1.448%and correlation coefficients higher than 0.999.This was further verified by benchmarking the new ensemble against several popular swarm intelligence algorithms.It is concluded that the proposed algorithms are far superior to the commonly adopted ones.展开更多
This research develops a comprehensive method to solve a combinatorial problem consisting of distribution system reconfiguration, capacitor allocation, and renewable energy resources sizing and siting simultaneously a...This research develops a comprehensive method to solve a combinatorial problem consisting of distribution system reconfiguration, capacitor allocation, and renewable energy resources sizing and siting simultaneously and to improve power system's accountability and system performance parameters. Due to finding solution which is closer to realistic characteristics, load forecasting, market price errors and the uncertainties related to the variable output power of wind based DG units are put in consideration. This work employs NSGA-II accompanied by the fuzzy set theory to solve the aforementioned multi-objective problem. The proposed scheme finally leads to a solution with a minimum voltage deviation, a maximum voltage stability, lower amount of pollutant and lower cost. The cost includes the installation costs of new equipment, reconfiguration costs, power loss cost, reliability cost, cost of energy purchased from power market, upgrade costs of lines and operation and maintenance costs of DGs. Therefore, the proposed methodology improves power quality, reliability and security in lower costs besides its preserve, with the operational indices of power distribution networks in acceptable level. To validate the proposed methodology's usefulness, it was applied on the IEEE 33-bus distribution system then the outcomes were compared with initial configuration.展开更多
China began the research and development of renewable energy generation since 1970s, in particular in the Eighth Five-year Plan period, the State made closer attention to the research and development of renewable ener...China began the research and development of renewable energy generation since 1970s, in particular in the Eighth Five-year Plan period, the State made closer attention to the research and development of renewable energy, therefore the technical level, application scale and economic, social benefits have seen greater progress. The combined capacity of renewable energy generation reached 100 MW at the end of 1994. And it is planned a combined capacity of 1236 MW will be targeted for the year 2000.展开更多
In 2010, over 300 billion yuan ($47.31 billion) are invested in renewable energy sources in China, outranking every other country. Hence, China has become one of the world’s biggest investors in renewable energy sour...In 2010, over 300 billion yuan ($47.31 billion) are invested in renewable energy sources in China, outranking every other country. Hence, China has become one of the world’s biggest investors in renewable energy sources.展开更多
Demand for power in Malaysia is projected to double the current demand in 2030. The current fuel mix for power generation is heavily dependent on fossil fuels. This has created energy supply and environmental sustaina...Demand for power in Malaysia is projected to double the current demand in 2030. The current fuel mix for power generation is heavily dependent on fossil fuels. This has created energy supply and environmental sustainability concerns to the industry. Furthermore, at the recent United Nations Climate Change Conference 2009-15th Conference of Parties （COP15）, Malaysia had given the commitment to voluntary reduction of up to 40% in terms of emissions intensity of GDP by the year 2020 compared to 2005 levels. Renewable energy （RE） provides the best alternative in addressing these issues. In 2001, RE was regarded as the fifth fuel in the new Five Fuel Strategy of the National Energy Policy. Small Renewable Energy Program （SREP） was launched with the main objective of supporting the government＇s strategy to intensify the development of RE as the fifth fuel resource. Biomass, the largest amongst the main RE resources available, can be used for heat and power generation. With optimum utilization, the value ofbiomass resources in Malaysia is estimated to be more than RM 500 billion （USD 156 billion） over the next 20 years. Malaysia has the capacity to use renewable energy resources to address the national energy agenda.展开更多
The accelerating global energy transition,driven by climate imperatives and technological advancements,demands fundamen-tal transformations in power systems.Smart grids,characterized by cyber-physical integration,dist...The accelerating global energy transition,driven by climate imperatives and technological advancements,demands fundamen-tal transformations in power systems.Smart grids,characterized by cyber-physical integration,distributed renewable resources,and data-driven intelligence,have emerged as the backbone of this evolution.This convergence,however,introduces unprecedented complexities in resilience,security,stability,and market operation.This special issue presents five pivotal studies addressing these interconnected challenges,offering novel methodologies and insights to advance the efficiency,resilience,and sustainability of modern power systems.展开更多
Renewable energy (RE) has been attached high attention around the world due to its carbon-free and indigenous production in a sustainable way. China enjoys plenty of renewable energy resources, particularly the wind, ...Renewable energy (RE) has been attached high attention around the world due to its carbon-free and indigenous production in a sustainable way. China enjoys plenty of renewable energy resources, particularly the wind, solar, hydro- and biomass energy, which could be a sound basis for a large-scale exploitation. This report examines the current status of RE technology and industry, analyzes the challenges of promoting RE in China. In order to pave the way for a long-term development of RE, this paper outlines the basic principles and priorities for individual RE technology. In line with these, the paper puts forward the RE targets and further describes the RE road map by 2020, 2030 and extend to 2050, taking consideration of China’s RE resources, industrial basis and energy demand etc. At last, this paper provides some recommendations to ensure the achievements of the RE targets.展开更多
An autonomous microgrid that runs on renewable energy sources is presented in this article.It has a supercon-ducting magnetic energy storage(SMES)device,wind energy-producing devices,and an energy storage battery.Howe...An autonomous microgrid that runs on renewable energy sources is presented in this article.It has a supercon-ducting magnetic energy storage(SMES)device,wind energy-producing devices,and an energy storage battery.However,because such microgrids are nonlinear and the energy they create varies with time,controlling and managing the energy inside them is a difficult issue.Fractional-order proportional integral(FOPI)controller is recommended for the current research to enhance a standalone microgrid’s energy management and performance.The suggested dedicated control for the SMES comprises two loops:the outer loop,which uses the FOPI to regulate the DC-link voltage,and the inner loop,responsible for regulating the SMES current,is constructed using the intelligent FOPI(iFOPI).The FOPI+iFOPI parameters are best developed using the dandelion optimizer(DO)approach to achieve the optimum performance.The suggested FOPI+iFOPI controller’s performance is contrasted with a conventional PI controller for variations in wind speed and microgrid load.The optimal FOPI+iFOPI controller manages the voltage and frequency of the load.The behavior of the microgrid as a reaction to step changes in load and wind speed was measured using the proposed controller.MATLAB simulations were used to evaluate the recommended system’s performance.The results of the simulations showed that throughout all interruptions,the recommended microgrid provided the load with AC power with a constant amplitude and frequency.In addition,the required load demand was accurately reduced.Furthermore,the microgrid functioned incredibly well despite SMES and varying wind speeds.Results obtained under identical conditions were compared with and without the best FOPI+iFOPI controller.When utilizing the optimal FOPI+iFOPI controller with SMES,it was found that the microgrid performed better than the microgrid without SMES.展开更多
Solar energy, as a renewable resource, is an effective solution to the current global energy shortage problem. To actively respond to the call for "carbon peak" and "carbon neutrality", solar cell ...Solar energy, as a renewable resource, is an effective solution to the current global energy shortage problem. To actively respond to the call for "carbon peak" and "carbon neutrality", solar cell industry has experienced unprecedented development. The full utilization of solar energy resources remains an urgent issue to be addressed.展开更多
The Yellow River has a vast catchment area and historically it is the mother river of the Chinese nation. Now it serves as one of the main theatres for the on-going national campaign to develop China's western... The Yellow River has a vast catchment area and historically it is the mother river of the Chinese nation. Now it serves as one of the main theatres for the on-going national campaign to develop China's western hinterland.……展开更多
This paper presents a comprehensive review of previous research based on scientific papers,technical reports,and published academic theses.The review focuses on studies and investigations concerning the application of...This paper presents a comprehensive review of previous research based on scientific papers,technical reports,and published academic theses.The review focuses on studies and investigations concerning the application of rubberbased biopolymers as modifiers in asphalt binders and mixtures,alongside relevant existing literature,encompassing their influence on asphalt binders and mixtures as well as their binder-aggregate interface performance.Incorporating rubber-based biopolymers into base asphalt significantly enhances the viscosity,complex modulus,rutting parameters,and recovery percentage while reducing non-recoverable compliance and phase angle.These alterations indicate that rubber-based biopolymer-modified asphalt displays superior resistance to permanent deformation,surpassing base asphalt's linear and non-linear rheological properties.Besides,rubber-based biopolymers alter the functional groups within the base asphalt due to the interaction in the asphalt matrix,especially afterthe aging process.These biopolymers are uniformly dispersed throughoutthe asphalt matrix,facilitated by the interconnected elastic networks among the biopolymer molecules.This improves the rheological and mechanical properties of both asphalt binders and mixtures.It is recommended that further studies investigate the combined effects of rubber-based biopolymers with other materials commonly used in asphalt modifications,such as nanomaterials and biomaterials,on the non-linear rheological and microstructural properties of asphalt binders,as well asthe performance of asphalt mixtures.Advanced simulation and modeling techniques,such as molecular dynamic simulation and machine learning should be employed to understand the behavior of rubber-based biopolymermodified asphalt binders and mixtures in various aging and loading situations.展开更多
The use of biomass feedstocks for the manufacture of high-performance polymers can help expand their range of applications and reduce their dependence on finite fossil resources.However,improving the heat resistance a...The use of biomass feedstocks for the manufacture of high-performance polymers can help expand their range of applications and reduce their dependence on finite fossil resources.However,improving the heat resistance and hydrophilicity of bio-based polyesters remains a significant challenge.Herein,we introduce N,N'-trans-1,4-cyclohexane-bis(pyrrolidone-4-methylcarboxylate)(CBPC),a novel bio-based tricyclic dibasic ester synthesized from renewable dimethyl itaconic acid and trans-1,4-cyclohexane diamine via an aza-Michael addition reaction.As a unique comonomer,CBPC features a rigid tricyclic backbone that significantly enhances chain packing and thermal stability,whereas its pyrrolidone side groups impart tunable polarity and improved hydrophilicity.Using CBPC,diphenyl carbonate,and 1,4-butylene glycol,a series of PBCC copolymers with 10 mol%-30 mol%CBPC was synthesized via ester-exchange and melt polycondensation methods.Incorporation of CBPC raised the melting temperature(Tm)from 56.8℃to 225.8℃and the initial decomposition temperature(Td5%)from 258.0℃to 306.7℃,positioning PBCC among the most heat-resistant bio-based polyesters reported.Additionally,the pyrrolidone units enabled transformation from hydrophobic to hydrophilic.This study demonstrates that CBPC is an effective and innovative building block for the design of bio-based polymers with enhanced thermal and surface properties,offering a promising strategy for the development of high-performance sustainable materials.展开更多
Renewable generation is rapidly increasing and transforming power systems toward“new-type power systems”.The integration of renewable energy resources necessitates a shift from conventional grid-following converters...Renewable generation is rapidly increasing and transforming power systems toward“new-type power systems”.The integration of renewable energy resources necessitates a shift from conventional grid-following converters(GFLs)to advanced grid-forming controls.Although grid-forming converters(GFMs)provide grid support and enhance system stability under weak grid conditions,their deployment requires more robust hardware,complex control algorithms and system operation constraints,resulting in planning and operational trade-offs between system stability and cost efficiency.This paper studies the underexplored question of how many GFMs are needed from a techno-economic perspective.The holistic analysis integrates long-term planning,short-term operational strategies and dynamic stability considerations,thereby supporting large-scale renewable integration while ensuring system security and economic benefits.展开更多
The shortage of petroleum has resulted in worldwide efforts to produce chemicals from renewable resources. Among these attempts, the possibility of producing acrylic acid from biomass has caught the eye of many resear...The shortage of petroleum has resulted in worldwide efforts to produce chemicals from renewable resources. Among these attempts, the possibility of producing acrylic acid from biomass has caught the eye of many researchers. Converting the carbohydrates first to lactic acid by fermentation and then dehydrating lactic acid to acrylic acid is hitherto the most effective way for producing acrylic acid from biomass. While the lactic acid fer- mentation has been commercialized since longer times, the dehydration process of lactic acid is still under development because of its low yield. Further efforts should be made before this process became economically feasible. Because of the existence of acrylic acid pathways in some microorganisms, strain improvement and metabolic engineering provides also a possibilitv to produce acrylic acid directly from biomass by fermentation.展开更多
Since the production cost of biodiesel is now the main hurdle limiting their applicability in some areas, catalytic cracking reactions represent an alternative route to utilization of vegetable oils and animal fats. H...Since the production cost of biodiesel is now the main hurdle limiting their applicability in some areas, catalytic cracking reactions represent an alternative route to utilization of vegetable oils and animal fats. Hence, catalytic transformation of oils and fats was carried out in a laboratory-scale two-stage riser fluid catalytic cracking （TSRFCC） unit in this work. The results show that oils and fats can be used as FCC feed singly or co-feeding with vacuum gas oil （VGO）, which can give high yield （by mass）of liquefied petroleum gas （LPG）, C2-C4 oletms, tor example 45% LPG, 47% C2-C4 olefins, and 77.6% total liquid yield produced with palm oil cracking. Co-feeding with VGO gives a high yield of LPG （39.1%） and propylene （18.1%）. And oxygen element content is very low （about 0.5%） in liquid products, hence, oxygen is removed in the form of H2O, CO and CO2. At the same time, high concentration of aromatics （C7-C9 aromatics predominantly） in the gasoline fraction is obtained after TSRFCC reaction of palm oil, as a result of large amount of hydrogen-transfer, cyclization and aromatization reactions, Additionally, most of properties of produced gasoline and diesel oil fuel meet the requirements of national standards, containing little sulfur. So TSRFCC technology is thought to be an alternative processing technology leading to production of clean fuels and light olefins.展开更多
This study presents an overview of the current status of hydrogen production in relation to the global requirement for energy and resources.Subsequently,it symmetrically outlines the advantages and disadvantages of va...This study presents an overview of the current status of hydrogen production in relation to the global requirement for energy and resources.Subsequently,it symmetrically outlines the advantages and disadvantages of various production routes including fossil fuel/biomass conversion,water electrolysis,microbial fermentation,and photocatalysis(PC),in terms of their technologies,economy,energy consumption,and costs.Considering the characteristics of hydrogen energy and the current infrastructure issues,it highlights that onsite production is indispensable and convenient for some special occasions.Finally,it briefly summarizes the current industrialization situation and presents future development and research directions,such as theoretical research strengthening,renewable raw material development,process coupling,and sustainable energy use.展开更多
A mild and simple process for the effective oxidation of 5-hydroxymethylfurfural（HMF） into 2,5-diformylfuran（DFF） has been developed using Na NO2 as the oxidant. Some important reaction parameters were investigate...A mild and simple process for the effective oxidation of 5-hydroxymethylfurfural（HMF） into 2,5-diformylfuran（DFF） has been developed using Na NO2 as the oxidant. Some important reaction parameters were investigated to optimize the oxidation of HMF into DFF. It was found that the reaction solvent was very crucial for this reaction. Trifluoroacetic acid was the best solvent for the oxidation of HMF into DFF by Na NO2.Under the optimal reaction condition, almost quantitative HMF conversion and high DFF yield of 90.4% were obtained after 1 h at room temperature.展开更多
基金supported by the Natural Science Foundation of Fujian Province,China(No.2021J05266)the Talents Introduction Program of Xiamen University of Technology,China(No.YKJ19019R)+1 种基金the Young and Middle-aged Teachers Education Scientific Research Project of Fujian Province(No.JAT190657)supported under Australian Research Council/Discovery Early Career Researcher Award(DECRA)funding scheme(project No.DE230100180).
文摘Nowadays,the predominant source for approximately 90%of epoxy resin materials worldwide is the diglycidyl ether of bisphenol A(DGEBA).However,the increasing recognition of environmental concerns,such as global warming and the depletion of petroleum reserves,necessitates the exploration of alternative options,specifically bio-epoxy resin derived from sustainable resources.Nonetheless,the inadequate flame retardancy of bio-epoxy resin presents a notable drawback,limiting its applicability in high-risk environments.The objective of this review article is to provide a concise overview of the latest and upto-date advances in flame-retardant epoxy resins derived from sustainable sources.Firstly,the discussion encompasses inherently flame-retardant bio-based epoxy resins,considering both bio-based epoxy monomers and bio-based curing agents,focusing on their flame retardancy and mechanical properties.Furthermore,the utilization of phosphorus-containing and silicon-containing additives in bio-based epoxy is explored.Additionally,a comprehensive evaluation of partially bio-based intrinsically flame retardant epoxy resins is provided.Finally,this article offers an extensive survey of the current state-of-the-art in the field and presents future perspectives,serving as a valuable resource for researchers engaged in the study of flame-retardant epoxy resins derived from sustainable resources.
基金support from the National Natural Science Foundation of China(32271809,31890774)National Natural Science Foundation for Youth(32001283)Fundamental Research Funds for the Central Nonprofit Research Institution of Chinese Academy of Forestry(CAFYBB2021QB004).
文摘In recent years,bio-based polymeric materials have attracted increased attention owing to their distinctive prop-erties,including richness,sustainability,environmental friendliness,and biodegradability.This article reviews the recent developments and potential trends of research on bio-based polymers synthesized from various re-newable resources.It covers the resources and structures of bio-based monomers,the methods of synthesis and properties of bio-based thermoplastics and thermosets,the production of bio-based composites and the fabrica-tion of functional bio-based polymers.Finally,the technological and future challenges related to enabling these materials to apply in the industry have been discussed,together with the potential solutions or directions.
文摘In COVID-19 pandemic in the world, alcohol (ethanol) can be listed as a sterilizing disinfectant. It absolutely played a Messianic function on the sterilization effect. And it is said that it has one more function called “salinity reduction” but that function is not widely known. The two functions (Sterilization & Salinity Reduction) mentioned above are extremely important regarding the theme of “raw seawater into beverage” in this study. It is thought that if the two functions are achieved other water quality items such as NO<sup>-</sup>2</sub> and other items can be cleared with comparative ease. To put briefly the feature of modern waterworks in a word, it can be said that “source of water is river water and its sterilization is chlorine”. In this study, we set up it with a completely new sanitization method (great reset), that is, “source of water is mixtures (seawater and rainwater) and its sterilization is ethanol”. And it can be also expected that the capture and storage of ethanol as a renewable resource is basically possible by utilizing sunlight as a natural power. Therefore, we think that this resolves itself into a question of the choice (sense of value/culture) of the users. It means that how users finally balance out with three factors, i.e., cost, risk (safety) and benefit. Based on the viewpoint mentioned above, we examined the possibility of raw seawater into beverage using ethanol as a renewable resource to create humankind’s wisdom to the settlement (breakthrough) of the water scarcity in the world including Asia and Africa. As a result, we have obtained the new findings that suggest the possibility of raw seawater into beverage using ethanol as a renewable resource.
文摘In order to achieve a highly accurate estimation of solar energy resource potential,a novel hybrid ensemble-learning approach,hybridizing Advanced Squirrel-Search Optimization Algorithm(ASSOA)and support vector regression,is utilized to estimate the hourly tilted solar irradiation for selected arid regions in Algeria.Long-term measured meteorological data,including mean-air temperature,relative humidity,wind speed,alongside global horizontal irradiation and extra-terrestrial horizontal irradiance,were obtained for the two cities of Tamanrasset-and-Adrar for two years.Five computational algorithms were considered and analyzed for the suitability of estimation.Further two new algorithms,namely Average Ensemble and Ensemble using support vector regression were developed using the hybridization approach.The accuracy of the developed models was analyzed in terms of five statistical error metrics,as well as theWilcoxon rank-sum and ANOVA test.Among the previously selected algorithms,K Neighbors Regressor and support vector regression exhibited good performances.However,the newly proposed ensemble algorithms exhibited even better performance.The proposed model showed relative root mean square errors lower than 1.448%and correlation coefficients higher than 0.999.This was further verified by benchmarking the new ensemble against several popular swarm intelligence algorithms.It is concluded that the proposed algorithms are far superior to the commonly adopted ones.
文摘This research develops a comprehensive method to solve a combinatorial problem consisting of distribution system reconfiguration, capacitor allocation, and renewable energy resources sizing and siting simultaneously and to improve power system's accountability and system performance parameters. Due to finding solution which is closer to realistic characteristics, load forecasting, market price errors and the uncertainties related to the variable output power of wind based DG units are put in consideration. This work employs NSGA-II accompanied by the fuzzy set theory to solve the aforementioned multi-objective problem. The proposed scheme finally leads to a solution with a minimum voltage deviation, a maximum voltage stability, lower amount of pollutant and lower cost. The cost includes the installation costs of new equipment, reconfiguration costs, power loss cost, reliability cost, cost of energy purchased from power market, upgrade costs of lines and operation and maintenance costs of DGs. Therefore, the proposed methodology improves power quality, reliability and security in lower costs besides its preserve, with the operational indices of power distribution networks in acceptable level. To validate the proposed methodology's usefulness, it was applied on the IEEE 33-bus distribution system then the outcomes were compared with initial configuration.
文摘China began the research and development of renewable energy generation since 1970s, in particular in the Eighth Five-year Plan period, the State made closer attention to the research and development of renewable energy, therefore the technical level, application scale and economic, social benefits have seen greater progress. The combined capacity of renewable energy generation reached 100 MW at the end of 1994. And it is planned a combined capacity of 1236 MW will be targeted for the year 2000.
文摘In 2010, over 300 billion yuan ($47.31 billion) are invested in renewable energy sources in China, outranking every other country. Hence, China has become one of the world’s biggest investors in renewable energy sources.
文摘Demand for power in Malaysia is projected to double the current demand in 2030. The current fuel mix for power generation is heavily dependent on fossil fuels. This has created energy supply and environmental sustainability concerns to the industry. Furthermore, at the recent United Nations Climate Change Conference 2009-15th Conference of Parties （COP15）, Malaysia had given the commitment to voluntary reduction of up to 40% in terms of emissions intensity of GDP by the year 2020 compared to 2005 levels. Renewable energy （RE） provides the best alternative in addressing these issues. In 2001, RE was regarded as the fifth fuel in the new Five Fuel Strategy of the National Energy Policy. Small Renewable Energy Program （SREP） was launched with the main objective of supporting the government＇s strategy to intensify the development of RE as the fifth fuel resource. Biomass, the largest amongst the main RE resources available, can be used for heat and power generation. With optimum utilization, the value ofbiomass resources in Malaysia is estimated to be more than RM 500 billion （USD 156 billion） over the next 20 years. Malaysia has the capacity to use renewable energy resources to address the national energy agenda.
文摘The accelerating global energy transition,driven by climate imperatives and technological advancements,demands fundamen-tal transformations in power systems.Smart grids,characterized by cyber-physical integration,distributed renewable resources,and data-driven intelligence,have emerged as the backbone of this evolution.This convergence,however,introduces unprecedented complexities in resilience,security,stability,and market operation.This special issue presents five pivotal studies addressing these interconnected challenges,offering novel methodologies and insights to advance the efficiency,resilience,and sustainability of modern power systems.
文摘Renewable energy (RE) has been attached high attention around the world due to its carbon-free and indigenous production in a sustainable way. China enjoys plenty of renewable energy resources, particularly the wind, solar, hydro- and biomass energy, which could be a sound basis for a large-scale exploitation. This report examines the current status of RE technology and industry, analyzes the challenges of promoting RE in China. In order to pave the way for a long-term development of RE, this paper outlines the basic principles and priorities for individual RE technology. In line with these, the paper puts forward the RE targets and further describes the RE road map by 2020, 2030 and extend to 2050, taking consideration of China’s RE resources, industrial basis and energy demand etc. At last, this paper provides some recommendations to ensure the achievements of the RE targets.
基金This research was funded by the Deputyship for Research and Innovation,Ministry of Education,Saudi Arabia,through the University of Tabuk,Grant Number S-1443-0123.
文摘An autonomous microgrid that runs on renewable energy sources is presented in this article.It has a supercon-ducting magnetic energy storage(SMES)device,wind energy-producing devices,and an energy storage battery.However,because such microgrids are nonlinear and the energy they create varies with time,controlling and managing the energy inside them is a difficult issue.Fractional-order proportional integral(FOPI)controller is recommended for the current research to enhance a standalone microgrid’s energy management and performance.The suggested dedicated control for the SMES comprises two loops:the outer loop,which uses the FOPI to regulate the DC-link voltage,and the inner loop,responsible for regulating the SMES current,is constructed using the intelligent FOPI(iFOPI).The FOPI+iFOPI parameters are best developed using the dandelion optimizer(DO)approach to achieve the optimum performance.The suggested FOPI+iFOPI controller’s performance is contrasted with a conventional PI controller for variations in wind speed and microgrid load.The optimal FOPI+iFOPI controller manages the voltage and frequency of the load.The behavior of the microgrid as a reaction to step changes in load and wind speed was measured using the proposed controller.MATLAB simulations were used to evaluate the recommended system’s performance.The results of the simulations showed that throughout all interruptions,the recommended microgrid provided the load with AC power with a constant amplitude and frequency.In addition,the required load demand was accurately reduced.Furthermore,the microgrid functioned incredibly well despite SMES and varying wind speeds.Results obtained under identical conditions were compared with and without the best FOPI+iFOPI controller.When utilizing the optimal FOPI+iFOPI controller with SMES,it was found that the microgrid performed better than the microgrid without SMES.
文摘Solar energy, as a renewable resource, is an effective solution to the current global energy shortage problem. To actively respond to the call for "carbon peak" and "carbon neutrality", solar cell industry has experienced unprecedented development. The full utilization of solar energy resources remains an urgent issue to be addressed.
文摘 The Yellow River has a vast catchment area and historically it is the mother river of the Chinese nation. Now it serves as one of the main theatres for the on-going national campaign to develop China's western hinterland.……
基金the Ministry of Higher Education Malaysia for providing the Fundamental Research Grant Scheme with Project Code FRGS/1/2021/TK01/USM/02/1,which facilitated the execution of this researchThe authors also appreciate the support from Universiti Sains Malaysia through the Research University Individual(RUI)Grant(1001.PAWAM.8014140).
文摘This paper presents a comprehensive review of previous research based on scientific papers,technical reports,and published academic theses.The review focuses on studies and investigations concerning the application of rubberbased biopolymers as modifiers in asphalt binders and mixtures,alongside relevant existing literature,encompassing their influence on asphalt binders and mixtures as well as their binder-aggregate interface performance.Incorporating rubber-based biopolymers into base asphalt significantly enhances the viscosity,complex modulus,rutting parameters,and recovery percentage while reducing non-recoverable compliance and phase angle.These alterations indicate that rubber-based biopolymer-modified asphalt displays superior resistance to permanent deformation,surpassing base asphalt's linear and non-linear rheological properties.Besides,rubber-based biopolymers alter the functional groups within the base asphalt due to the interaction in the asphalt matrix,especially afterthe aging process.These biopolymers are uniformly dispersed throughoutthe asphalt matrix,facilitated by the interconnected elastic networks among the biopolymer molecules.This improves the rheological and mechanical properties of both asphalt binders and mixtures.It is recommended that further studies investigate the combined effects of rubber-based biopolymers with other materials commonly used in asphalt modifications,such as nanomaterials and biomaterials,on the non-linear rheological and microstructural properties of asphalt binders,as well asthe performance of asphalt mixtures.Advanced simulation and modeling techniques,such as molecular dynamic simulation and machine learning should be employed to understand the behavior of rubber-based biopolymermodified asphalt binders and mixtures in various aging and loading situations.
基金financially supported by the Provincial Project of Science and Technology(No.2023112258)Tianshan Talent Training Program(No.2024TSYCCX0112)+1 种基金Talent Introduction and Start Foundation for Young Scientists of Shihezi University(No.2022ZK004)Program for Young Innovative Talents of Shihezi University(No.CXFZ202302)。
文摘The use of biomass feedstocks for the manufacture of high-performance polymers can help expand their range of applications and reduce their dependence on finite fossil resources.However,improving the heat resistance and hydrophilicity of bio-based polyesters remains a significant challenge.Herein,we introduce N,N'-trans-1,4-cyclohexane-bis(pyrrolidone-4-methylcarboxylate)(CBPC),a novel bio-based tricyclic dibasic ester synthesized from renewable dimethyl itaconic acid and trans-1,4-cyclohexane diamine via an aza-Michael addition reaction.As a unique comonomer,CBPC features a rigid tricyclic backbone that significantly enhances chain packing and thermal stability,whereas its pyrrolidone side groups impart tunable polarity and improved hydrophilicity.Using CBPC,diphenyl carbonate,and 1,4-butylene glycol,a series of PBCC copolymers with 10 mol%-30 mol%CBPC was synthesized via ester-exchange and melt polycondensation methods.Incorporation of CBPC raised the melting temperature(Tm)from 56.8℃to 225.8℃and the initial decomposition temperature(Td5%)from 258.0℃to 306.7℃,positioning PBCC among the most heat-resistant bio-based polyesters reported.Additionally,the pyrrolidone units enabled transformation from hydrophobic to hydrophilic.This study demonstrates that CBPC is an effective and innovative building block for the design of bio-based polymers with enhanced thermal and surface properties,offering a promising strategy for the development of high-performance sustainable materials.
基金supported in part by the Carbon Neutrality and Energy System Transformation project and in part by EPSRC under Grant EP/Y025946/1.
文摘Renewable generation is rapidly increasing and transforming power systems toward“new-type power systems”.The integration of renewable energy resources necessitates a shift from conventional grid-following converters(GFLs)to advanced grid-forming controls.Although grid-forming converters(GFMs)provide grid support and enhance system stability under weak grid conditions,their deployment requires more robust hardware,complex control algorithms and system operation constraints,resulting in planning and operational trade-offs between system stability and cost efficiency.This paper studies the underexplored question of how many GFMs are needed from a techno-economic perspective.The holistic analysis integrates long-term planning,short-term operational strategies and dynamic stability considerations,thereby supporting large-scale renewable integration while ensuring system security and economic benefits.
文摘The shortage of petroleum has resulted in worldwide efforts to produce chemicals from renewable resources. Among these attempts, the possibility of producing acrylic acid from biomass has caught the eye of many researchers. Converting the carbohydrates first to lactic acid by fermentation and then dehydrating lactic acid to acrylic acid is hitherto the most effective way for producing acrylic acid from biomass. While the lactic acid fer- mentation has been commercialized since longer times, the dehydration process of lactic acid is still under development because of its low yield. Further efforts should be made before this process became economically feasible. Because of the existence of acrylic acid pathways in some microorganisms, strain improvement and metabolic engineering provides also a possibilitv to produce acrylic acid directly from biomass by fermentation.
基金the Major Research Plan of PetroChina Company Limited (07-03D-01-01-02-02)
文摘Since the production cost of biodiesel is now the main hurdle limiting their applicability in some areas, catalytic cracking reactions represent an alternative route to utilization of vegetable oils and animal fats. Hence, catalytic transformation of oils and fats was carried out in a laboratory-scale two-stage riser fluid catalytic cracking （TSRFCC） unit in this work. The results show that oils and fats can be used as FCC feed singly or co-feeding with vacuum gas oil （VGO）, which can give high yield （by mass）of liquefied petroleum gas （LPG）, C2-C4 oletms, tor example 45% LPG, 47% C2-C4 olefins, and 77.6% total liquid yield produced with palm oil cracking. Co-feeding with VGO gives a high yield of LPG （39.1%） and propylene （18.1%）. And oxygen element content is very low （about 0.5%） in liquid products, hence, oxygen is removed in the form of H2O, CO and CO2. At the same time, high concentration of aromatics （C7-C9 aromatics predominantly） in the gasoline fraction is obtained after TSRFCC reaction of palm oil, as a result of large amount of hydrogen-transfer, cyclization and aromatization reactions, Additionally, most of properties of produced gasoline and diesel oil fuel meet the requirements of national standards, containing little sulfur. So TSRFCC technology is thought to be an alternative processing technology leading to production of clean fuels and light olefins.
基金the National Natural Science Foundation of China under Grant No.20906063the Liaoning BaiQianWan Talents Program under Grant No.2018921046+1 种基金the Scientific Research Project of Liaoning Provincial Department of Education under Grant No.LJGD2020002the Shenyang Youth Science and Technology Project under Grant No.RC200325.
文摘This study presents an overview of the current status of hydrogen production in relation to the global requirement for energy and resources.Subsequently,it symmetrically outlines the advantages and disadvantages of various production routes including fossil fuel/biomass conversion,water electrolysis,microbial fermentation,and photocatalysis(PC),in terms of their technologies,economy,energy consumption,and costs.Considering the characteristics of hydrogen energy and the current infrastructure issues,it highlights that onsite production is indispensable and convenient for some special occasions.Finally,it briefly summarizes the current industrialization situation and presents future development and research directions,such as theoretical research strengthening,renewable raw material development,process coupling,and sustainable energy use.
基金supported by the National Natural Science Foundation of China(21272065)Scientific Research Fund of Hunan Provincial Education Department(13C562+2 种基金15C0816)Outstanding Youth Project of Hunan Provincial Education Department(15B134)the funding offered by China Scholarship Council(201506720018)
文摘A mild and simple process for the effective oxidation of 5-hydroxymethylfurfural（HMF） into 2,5-diformylfuran（DFF） has been developed using Na NO2 as the oxidant. Some important reaction parameters were investigated to optimize the oxidation of HMF into DFF. It was found that the reaction solvent was very crucial for this reaction. Trifluoroacetic acid was the best solvent for the oxidation of HMF into DFF by Na NO2.Under the optimal reaction condition, almost quantitative HMF conversion and high DFF yield of 90.4% were obtained after 1 h at room temperature.
