The atmospheric corrosion monitoring(ACM)technique has been widely employed to track the real-time corrosion behavior of metal materials.However,limited studies have applied ACM to the corrosion protection properties ...The atmospheric corrosion monitoring(ACM)technique has been widely employed to track the real-time corrosion behavior of metal materials.However,limited studies have applied ACM to the corrosion protection properties of organic coatings.This study compared a bare epoxy coating with one containing zinc phosphate corrosion inhibitors,both applied on ACM sensors,to observe their corrosion protection properties over time.Coatings with artificial damage via scratches were exposed to immersion and alternating dry and wet environments,which allowed for monitoring galvanic corrosion currents in real-time.Throughout the corrosion tests,the ACM currents of the zinc phosphate/epoxy coating were considerably lower than those of the blank epoxy coating.The trend in ACM current variations closely matched the results obtained from regular electrochemical tests and surface analysis.This alignment highlights the potential of the ACM technique in evaluating the corrosion protection capabilities of organic coatings.Compared with the blank epoxy coating,the zinc phosphate/epoxy coating showed much-decreased ACM current values that confirmed the effective inhibition of zinc phosphate against steel corrosion beneath the damaged coating.展开更多
The Natural Forest Protection Project(NFPP),initiated by the Chinese government in 2000,is a crucial ecological construction project that has played a significant role in forest restoration in China.Forests in the Qin...The Natural Forest Protection Project(NFPP),initiated by the Chinese government in 2000,is a crucial ecological construction project that has played a significant role in forest restoration in China.Forests in the Qinghai-Tibet Plateau(QTP)serve as important habitats for many rare and endemic birds.Understanding the conservation efficiency of NFPP implementation on these birds holds significant practical significance.In this study,we utilized land use change matrices to analyze the forest changes in the QTP before and after NFPP implementation,predicted the potential spatial distribution of 16 nationally protected birds using Species Distribution Models(SDMs),and compared the impacts of this project on bird habitats under different carbon emission scenarios.Mann-Whitney U tests were employed to analyze the adaptation of different birds to forest changes during NFPP implementation.Our results showed that NFPP protected 172,398 km^(2) of primary forests and added 6379 km^(2) of secondary forests in our study area.The potential spatial distribution and sympatric species richness of the 16 protected birds slightly increased after NFPP implementation under different climate change scenarios,and NFPP implementation contributed to improving the potential spatial distribution of birds.Compared to newly established secondary forests,protected primary forests exhibited enhanced conservation for forest birds(Z-value>0 for six bird species,P<0.1),while being less suitable for non-forest birds(significantly unsuitable for three non-forest bird species,Z-value<0,P<0.05;non-significantly unsuitable for four non-forest bird species,Zvalue<0,P>0.1).This indicates that the protection of primary forests during NFPP implementation benefits forest bird conservation while the addition of secondary forests is beneficial to non-forest birds.To enhance the role of NFPP in avian conservation in the QTP,it is suggested to increase the landscape heterogeneity of forest,particularly in newly established secondary forests.展开更多
The protection of drinking water sources is vital to urban development and public health.In this study,the current situation of the mandatory protection area for drinking water source in the Pearl River Delta region w...The protection of drinking water sources is vital to urban development and public health.In this study,the current situation of the mandatory protection area for drinking water source in the Pearl River Delta region was investigated using a method combining Google Earth with the field survey.The gaps between management practices and legislation requirements were analyzed.Finally,several countermeasures for water resource protection were proposed as follows:to promote delineation in a more scientific way,to safeguard the sanctity of the law,to make better plan on water saving,and to encourage public participation in supervision and management.展开更多
In this paper,we generally summarize the main issues in the operational period of water conservancy and hydropower projects in China over the past several decades.First,the adverse impacts of these projects since the ...In this paper,we generally summarize the main issues in the operational period of water conservancy and hydropower projects in China over the past several decades.First,the adverse impacts of these projects since the technical guidelines were proposed in 2006 are analyzed.Then,combined with projects and experience from 2006 to 2014,the four main issues are summarized:(1) There exist many questions in the design and construction of fishways,which are useful for fish migration,and the migration effects are not as expected.(2) Temperature stratification affecting the downstream fish is the major impact of temperature,and alters fish spawning in the reproduction season.(3)Ecological base flow has been one of the primary questions of the last 30 years in China,the greatest related difficulty being quantification of the amount and flow process necessary to satisfy fish life history.(4) Fish habitat protection and restoration are popular topics in recent years with the development of river ecosystem restoration.Fish habitat loss due to the impacts of dam construction and habitat fragmentation has become more and more serious.These four issues are now the main difficulties in water project management,and interact with one another to bear combined effects on river ecosystems.The issues of eco-hydraulic consideration in the design period are the key factors.Finally,future priorities for research and practice of environmental protection for water conservancy and hydropower projects in China are proposed.The main purpose of this paper is to enhance the scientific research,monitoring,and assessment of operating effectiveness.展开更多
A novel mussel-inspired adhesive polymer(PHEA-DOPA) containing the 3,4-dihydroxyphenylalanine(DOPA) functional group based on polyaspartamide derivatives was synthesized. The corrosion protection of the waterborne...A novel mussel-inspired adhesive polymer(PHEA-DOPA) containing the 3,4-dihydroxyphenylalanine(DOPA) functional group based on polyaspartamide derivatives was synthesized. The corrosion protection of the waterborne epoxy coatings containing the adhesive polymers was investigated by electrochemical impedance spectroscopy(EIS). The results indicated that the PHEA-DOPA could improve the corrosion resistance of the waterborne epoxy coating. The corrosion products were also analyzed by Raman microspectroscopy(RM), indicating the formation of the insoluble DOPA-Fe complexes on the carbon steel surface. These complexes simultaneously acting as a passivating layer, can inhibit the process of corrosion at the metal-solution interface. The differential scanning calorimeter(DSC) measurement indicated that PHEA-DOPA can increase the crosslinking density of coating. The effect of O;on the protective mechanism of the PHEA-DOPA coating in a 3.5% NaCl solution was also evaluated by EIS. The results indicated that the barrier effect was significantly improved under aerated conditions because DOPA was oxidized to DOPA-quinone(Dq) by O;, which triggered the reaction with Fe ions that were released from the surface of the carbon steel. This led to more compact coatings.展开更多
Layered double hydroxide(LDH) has been widely developed in the field of corrosion and protection in recent years based on its unique characteristics including anion capacity, anion exchange ability, structure memory e...Layered double hydroxide(LDH) has been widely developed in the field of corrosion and protection in recent years based on its unique characteristics including anion capacity, anion exchange ability, structure memory effect, and barrier resistance. This paper comprehensively reviews recent work on the preparations, properties of LDH in the forms of powder and film and their applications in different environments in corrosion and protection. Some novel perspectives are also proposed at the end of the review for future research in corrosion and protection field.展开更多
Multi-terminal hybrid high-voltage direct current(HVDC)systems have been developed quickly in recent years in power transmission area.However,for voltage-source converter(VSC)stations in hybrid HVDC systems,no direct ...Multi-terminal hybrid high-voltage direct current(HVDC)systems have been developed quickly in recent years in power transmission area.However,for voltage-source converter(VSC)stations in hybrid HVDC systems,no direct current(DC)filters are required.In addition,the DC reactor is also not installed at the line end because the DC fault can be limited by the converter itself.This means that the boundary element at the line end is absent,and the single-ended protections used in line commutated converter(LCC)based HVDC(LCC-HVDC)systems or VSC-HVDC systems cannot distinguish the fault line in multi-terminal hybrid HVDC systems.This paper proposes a novel singleended DC protection strategy suitable for the multi-terminal hybrid HVDC system,which mainly applies the transient information and active injection concept to detect and distinguish the fault line.Compared with the single-ended protections used in LCC-HVDC and VSC-HVDC systems,the proposed protection strategy is not dependent on the line boundary element and is thus suitable for the multiterminal hybrid HVDC system.The corresponding simulation cases based on power systems computer aided design(PSCAD)/electromagnetic transients including DC(EMTDC)are carried out to verify the superiority of the proposed protection.展开更多
As the world’s largest developing country,the ability of China’s agricultural resource utilization to effectively support the current and future food security goals has been affected by a variety of factors(e.g.,tra...As the world’s largest developing country,the ability of China’s agricultural resource utilization to effectively support the current and future food security goals has been affected by a variety of factors(e.g.,transformed supply channels,tightening international situation and frequent emergencies)in recent years and has attracted extensive attention from the academic community subject to multiple factors.This study uses literature review,statistical analysis,and spatial analysis methods to systematically explore China’s food security situation in the context of farmland resource constraints.It is found that the demand-side pressures such as demographic changes,social class differentiation,and dietary structure adjustments derived from economic growth and rapid urbanization have placed extremely high expectations on food supply.However,the quantitative restrictions,utilization ways,and health risks of farmland resources on the supply side constitute a huge hidden concern that affects the stability of food production.Although China’s farmland protection system is undergoing a transition from focusing on quantity management to sustainable use,the matching and coordinating demand pressure and supply capacity for food security is unbalanced.Therefore,facing uncertain future development scenarios,policymakers should focus on building a resilient space for China’s farmland protection to withstand the interference of major emergencies.The existing farmland protection space policy can be integrated by establishing a national farmland strategic reserve system(based on resilient space),and further development of targeted use control measures for zoning,grading,and classification will help realize sustainable China’s farmland resources use.展开更多
A Ag@CuFe_(2)O_(4)@TiO_(2) nanocomposite film with high performance of photogenerated cathodic protection was prepared by hydrothermal and photoreduction methods.The results showed that when the CuFe_(2)O_(4) hydrothe...A Ag@CuFe_(2)O_(4)@TiO_(2) nanocomposite film with high performance of photogenerated cathodic protection was prepared by hydrothermal and photoreduction methods.The results showed that when the CuFe_(2)O_(4) hydrothermal reaction time was 6 h and the AgNO_(3) concentration was 0.1 M,the Ag@CuFe_(2)O_(4)@TiO_(2) nanocomposite material performed the best cathodic protection capability for 304 stainless steel(304SS).In this case,the protective potential achieved-930 mV(versus SCE)associated with the photocurrent density of 475μA/cm^(2),which was 14.8 times that of pure TiO_(2) nanowires.In the dark,the nanocomposite provided cathodic protection of up to 485 mV for 304SS.Due to the heterogeneous junctions at the two interfaces among the three kinds of nanocomposite materials,the build-in electric field was fabricated,which promoted the separation efficiency of photogenerated electrons and holes and effectively improved the photochemical cathodic protection of 304SS.展开更多
In this work,TiO_(2)nanotube arrays(NTAs)sensitized with MoS_(2)microspheres(MoS_(2)/TiO_(2)nanocomposites)were prepared on a flat Ti substrate via two-step anodization and hydrothermal method sequentially.TiO_(2)NTAs...In this work,TiO_(2)nanotube arrays(NTAs)sensitized with MoS_(2)microspheres(MoS_(2)/TiO_(2)nanocomposites)were prepared on a flat Ti substrate via two-step anodization and hydrothermal method sequentially.TiO_(2)NTAs were composed of many orderly nanotubes,whose large specific surface area was favorable for light absorption and MoS_(2)microsphere adhesion.The MoS_(2)microsphere as a narrow band gap semiconductor extended the TiO_(2)NTAs’absorption band edge to the visible region.The 2D structure of MoS_(2)microspheres and the construction of heterojunction electronic field at the interface of MoS_(2)microspheres and TiO_(2)NTAs promoted the separation of photoinduced carriers.The MoS_(2)/TiO_(2)nanocomposites could provide higher photoelectrochemical cathodic protection for 304 stainless steel(304 SS)under visible light than pristine TiO_(2)NTAs.展开更多
Corrosion protection has become an important issue as the amount of infrastructure construction in marine environment increased.Photocathodic protection is a promising method to reduce the corrosion of metals,and tita...Corrosion protection has become an important issue as the amount of infrastructure construction in marine environment increased.Photocathodic protection is a promising method to reduce the corrosion of metals,and titanium dioxide(TiO2) is the most widely used photoanode.This review summarizes the progress in TiO2 photo gene rated protection in recent years.Different types of semiconductors,including sulfides,metals,metal oxide s,polymers,and other materials,are used to design and modify TiO2.The strategy to dramatically improve the efficiency of photoactivity is proposed,and the mechanism is investigated in detail.Characterization methods are also introduced,including morphology testing,light absorption,photoelectrochemistry,and protected metal observation.This review aims to provide a comprehensive overview of Ti02 development and guide photocathodic protection.展开更多
Ecosystem services have become one of the core elements of ecosystem management and evaluation. As a key area of ecosystem services and for maintaining national ecological security, ecosystem changes and implementatio...Ecosystem services have become one of the core elements of ecosystem management and evaluation. As a key area of ecosystem services and for maintaining national ecological security, ecosystem changes and implementation effect evaluation are important in national key ecological function zones, for promoting the main function zone strategy and for improving the construction of an ecological civilization. This article studies the ecological zone of a tropical rainforest region in the central mountain area of Hainan Island, China. Multi-source satellite data and ground observation statistics are analyzed with geo-statistics method and ecological assessment model. The core analysis of this paper includes ecosystem patterns, quality and services. By means of spatial and temporal scale expansion and multidimensional space-time correlation analysis, the trends and stability characteristics of ecosystem changes are analyzed, and implementation effect evaluation is discussed. The analysis shows a variety of results. The proportion of forest area inside the ecological zone was significantly higher than the average level in Hainan Island. During 1990–2013, settlement gradually increased inside the ecological zone. After implementation of the zone in 2010, human activity intensity increased, with the main land use being urban construction and land reclamation. Water conservation in the ecological function zone was higher than that outside the zone. In general, it increased slightly, but had obvious fluctuations. Soil conservation inside the zone was also better than that outside. However, it demonstrated dramatic fluctuations and relatively poor stability during 1990–2013. The human disturbance index inside the zone was significantly lower than that outside, and had a lower biodiversity threat level. Especially in 2010–2013, the increased range of the human disturbance index inside the zone was significantly less than that outside.展开更多
Taking lightning-protection engineering of Wuhan Changshankou landfill and incineration plants for the example,in this article,we have discussed the integrated technology of direct lightning protection by early stream...Taking lightning-protection engineering of Wuhan Changshankou landfill and incineration plants for the example,in this article,we have discussed the integrated technology of direct lightning protection by early streamer emission lightning rod,lifting lightning rod and mobile lightning rod. Additionally,lightning protection methods and measures of landfill with large receiving area of lightning strike and landfill gas and incineration plant with irregular landfill cell are explored.展开更多
As we have borrowed the wisdom from biological neural network, the characteristic of interference- proof in information transferring process has been carefully studied. Our study includes the response of electrical-in...As we have borrowed the wisdom from biological neural network, the characteristic of interference- proof in information transferring process has been carefully studied. Our study includes the response of electrical-interference-proof circuit in electromagnetic environment, by means of bionics redesign. In this way, new principles, new technics and new ways are adopted to solve the unavoidable situations in traditional electro- magnet protection design. Based on the Boolean model, the complex bionic topological networks were firstly built and the charactoristics of degeneracy were analyzed, then the bidirectional actions between degeneracy in networks and the robustness of functions were proved in order to fill up the gap to deal with the need of interference-proof. Based on the creation of the neuron networks and the electrical synapses ' charac- teristic of plasticity, the impact of the distribution in the weight of synapse on the character of network self- recovery was studied afterwards so that the corresponding mechanism could be defined.展开更多
Via database technology, a perfect lightning protection integrated service work platform is established, thereby realizing paperless data management of routine business.
Huadianba in the Cangshan Mountain, a region where key ecosystem types and species under prior protection are concentrated, is the first choice for the comprehensive protection and development of biodiversity. In this...Huadianba in the Cangshan Mountain, a region where key ecosystem types and species under prior protection are concentrated, is the first choice for the comprehensive protection and development of biodiversity. In this study, natural conditions, location and current protection and development of Huadianba were introduced, major problems emerging in the protection and management were summarized, and pertinent measures were proposed as a reference for the scientific development and protection of Huadianba.展开更多
Metal corrosion causes significant economic losses,safety issues,and environmental pollution.Hence,its prevention is of immense research interest.Carbon dots(CDs)are a new class of zero-dimensional carbon nanomaterial...Metal corrosion causes significant economic losses,safety issues,and environmental pollution.Hence,its prevention is of immense research interest.Carbon dots(CDs)are a new class of zero-dimensional carbon nanomaterials,which have been considered for corrosion protection applications in recent years due to their corrosion inhibition effect,fluorescence,low toxicity,facile chemical modification,and cost-effectiveness.This study provides a comprehensive overview of the synthesis,physical and chemical properties,and anticorrosion mechanisms of functionalized CDs.First,the corrosion inhibition performance of different types of CDs is introduced,followed by discussion on their application in the development of smart protective coatings with self-healing and/or self-reporting properties.The effective barrier formed by CDs in the coatings can inhibit the spread of local damage and achieve self-healing behavior.In addition,diverse functional groups on CDs can interact with Fe^(3+)and H^(+)ions generated during the corrosion process;this interaction changes their fluorescence,thereby demonstrating self-reporting behavior.Moreover,challenges and prospects for the development of CD-based corrosion protection systems are also presented.展开更多
A novel three-dimensional hierarchical WO_(3)photoelectrode was prepared by solvothermal method,and ZnO was deposited on its surface by electrochemical method.The WO_(3)/ZnWO_(4)/ZnO multiphaseheterojunction photoelec...A novel three-dimensional hierarchical WO_(3)photoelectrode was prepared by solvothermal method,and ZnO was deposited on its surface by electrochemical method.The WO_(3)/ZnWO_(4)/ZnO multiphaseheterojunction photoelectrode was prepared by further annealing treatment to explore the photoinduced cathodic protection(CP)performance.Compared with WO_(3)and ZnO,the photoinduced CP and electron storage capacity performance of WO_(3)/ZnWO_(4)/ZnO is significantly improved in 3.5%NaCl solution without adding any hole scavenger.The electron storage capacity of the WO_(3)/ZnWO_(4)/ZnO heterojunction makes it possible to continuously protect metallic materials in the dark after switching off the light,which can realize long-term and effective photoinduced CP.展开更多
Semiconductor quantum dots with high quantum yield and photovoltaic conversion efficiency have ushered in a brilliant moment for constructing internal electric field heterojunctions for photogenerated cathodic protect...Semiconductor quantum dots with high quantum yield and photovoltaic conversion efficiency have ushered in a brilliant moment for constructing internal electric field heterojunctions for photogenerated cathodic protection applications.In this paper,TiO_(2)nanotubes grown vertically on the surface of titanium substrates were modified via a combination of conventional electrochemical oxidation and a one-step solvothermal pathway to sensitize with CuInS_(2)quantum dots.Compared with pure TiO_(2)photoelectrodes,the modification improves sunlight absorption efficiency and provides photoelectron cathodic protection to the 304 stainless steel(304 SS).Through 9 h solvothermal reaction,the CuInS_(2)/TiO_(2)coupled with protected 304 SS exhibited an excellent property when the simulated sunlight irradiation.Its mixed open circuit potential is negatively shifted to-0.99 V,at the mean time with a stable photocurrent density(118μA cm^(-2)).The results indicate that CuInS_(2)and TiO_(2)established a p-n heterojunction with wellmatched energy level,which can effectively facilitate the carrier separation and retain the strong redox capbility of photo-induced electrons and holes.展开更多
基金financially supported by the National Natural Science Foundation of China(No.52371049)the Young Elite Scientists Sponsorship Program by the China Association for Science and Technology(YESS,No.2020QNRC001)the National Science and Technology Resources Investigation Program of China(Nos.2021FY100603 and 2019FY101404)。
文摘The atmospheric corrosion monitoring(ACM)technique has been widely employed to track the real-time corrosion behavior of metal materials.However,limited studies have applied ACM to the corrosion protection properties of organic coatings.This study compared a bare epoxy coating with one containing zinc phosphate corrosion inhibitors,both applied on ACM sensors,to observe their corrosion protection properties over time.Coatings with artificial damage via scratches were exposed to immersion and alternating dry and wet environments,which allowed for monitoring galvanic corrosion currents in real-time.Throughout the corrosion tests,the ACM currents of the zinc phosphate/epoxy coating were considerably lower than those of the blank epoxy coating.The trend in ACM current variations closely matched the results obtained from regular electrochemical tests and surface analysis.This alignment highlights the potential of the ACM technique in evaluating the corrosion protection capabilities of organic coatings.Compared with the blank epoxy coating,the zinc phosphate/epoxy coating showed much-decreased ACM current values that confirmed the effective inhibition of zinc phosphate against steel corrosion beneath the damaged coating.
基金funded by Central Fiscal Forestry and Grassland Ecological Protection and Restoration Fund in 2022(grant number:HYGJ22069P(2022zfcg03469)-HT01)National Natural Science Foundation of China(grant number:3152010390332070452)。
文摘The Natural Forest Protection Project(NFPP),initiated by the Chinese government in 2000,is a crucial ecological construction project that has played a significant role in forest restoration in China.Forests in the Qinghai-Tibet Plateau(QTP)serve as important habitats for many rare and endemic birds.Understanding the conservation efficiency of NFPP implementation on these birds holds significant practical significance.In this study,we utilized land use change matrices to analyze the forest changes in the QTP before and after NFPP implementation,predicted the potential spatial distribution of 16 nationally protected birds using Species Distribution Models(SDMs),and compared the impacts of this project on bird habitats under different carbon emission scenarios.Mann-Whitney U tests were employed to analyze the adaptation of different birds to forest changes during NFPP implementation.Our results showed that NFPP protected 172,398 km^(2) of primary forests and added 6379 km^(2) of secondary forests in our study area.The potential spatial distribution and sympatric species richness of the 16 protected birds slightly increased after NFPP implementation under different climate change scenarios,and NFPP implementation contributed to improving the potential spatial distribution of birds.Compared to newly established secondary forests,protected primary forests exhibited enhanced conservation for forest birds(Z-value>0 for six bird species,P<0.1),while being less suitable for non-forest birds(significantly unsuitable for three non-forest bird species,Z-value<0,P<0.05;non-significantly unsuitable for four non-forest bird species,Zvalue<0,P>0.1).This indicates that the protection of primary forests during NFPP implementation benefits forest bird conservation while the addition of secondary forests is beneficial to non-forest birds.To enhance the role of NFPP in avian conservation in the QTP,it is suggested to increase the landscape heterogeneity of forest,particularly in newly established secondary forests.
文摘The protection of drinking water sources is vital to urban development and public health.In this study,the current situation of the mandatory protection area for drinking water source in the Pearl River Delta region was investigated using a method combining Google Earth with the field survey.The gaps between management practices and legislation requirements were analyzed.Finally,several countermeasures for water resource protection were proposed as follows:to promote delineation in a more scientific way,to safeguard the sanctity of the law,to make better plan on water saving,and to encourage public participation in supervision and management.
基金supported by a General Financial Grant from the China Postdoctoral Science Foundation(Grant No.2016M592404)the projects funded by the China Three Gorges Corporation(Grants No.0799556 and0799564)
文摘In this paper,we generally summarize the main issues in the operational period of water conservancy and hydropower projects in China over the past several decades.First,the adverse impacts of these projects since the technical guidelines were proposed in 2006 are analyzed.Then,combined with projects and experience from 2006 to 2014,the four main issues are summarized:(1) There exist many questions in the design and construction of fishways,which are useful for fish migration,and the migration effects are not as expected.(2) Temperature stratification affecting the downstream fish is the major impact of temperature,and alters fish spawning in the reproduction season.(3)Ecological base flow has been one of the primary questions of the last 30 years in China,the greatest related difficulty being quantification of the amount and flow process necessary to satisfy fish life history.(4) Fish habitat protection and restoration are popular topics in recent years with the development of river ecosystem restoration.Fish habitat loss due to the impacts of dam construction and habitat fragmentation has become more and more serious.These four issues are now the main difficulties in water project management,and interact with one another to bear combined effects on river ecosystems.The issues of eco-hydraulic consideration in the design period are the key factors.Finally,future priorities for research and practice of environmental protection for water conservancy and hydropower projects in China are proposed.The main purpose of this paper is to enhance the scientific research,monitoring,and assessment of operating effectiveness.
基金the National Key Technology Support Program of China(No.2014BAE12B01) for the financial support of this research
文摘A novel mussel-inspired adhesive polymer(PHEA-DOPA) containing the 3,4-dihydroxyphenylalanine(DOPA) functional group based on polyaspartamide derivatives was synthesized. The corrosion protection of the waterborne epoxy coatings containing the adhesive polymers was investigated by electrochemical impedance spectroscopy(EIS). The results indicated that the PHEA-DOPA could improve the corrosion resistance of the waterborne epoxy coating. The corrosion products were also analyzed by Raman microspectroscopy(RM), indicating the formation of the insoluble DOPA-Fe complexes on the carbon steel surface. These complexes simultaneously acting as a passivating layer, can inhibit the process of corrosion at the metal-solution interface. The differential scanning calorimeter(DSC) measurement indicated that PHEA-DOPA can increase the crosslinking density of coating. The effect of O;on the protective mechanism of the PHEA-DOPA coating in a 3.5% NaCl solution was also evaluated by EIS. The results indicated that the barrier effect was significantly improved under aerated conditions because DOPA was oxidized to DOPA-quinone(Dq) by O;, which triggered the reaction with Fe ions that were released from the surface of the carbon steel. This led to more compact coatings.
基金financially supported by the State Key Project of Research and Development (No. 2016YFC1100300)the National Natural Science Foundation of China (No. 21203158, 21773199, and 21621091)。
文摘Layered double hydroxide(LDH) has been widely developed in the field of corrosion and protection in recent years based on its unique characteristics including anion capacity, anion exchange ability, structure memory effect, and barrier resistance. This paper comprehensively reviews recent work on the preparations, properties of LDH in the forms of powder and film and their applications in different environments in corrosion and protection. Some novel perspectives are also proposed at the end of the review for future research in corrosion and protection field.
文摘Multi-terminal hybrid high-voltage direct current(HVDC)systems have been developed quickly in recent years in power transmission area.However,for voltage-source converter(VSC)stations in hybrid HVDC systems,no direct current(DC)filters are required.In addition,the DC reactor is also not installed at the line end because the DC fault can be limited by the converter itself.This means that the boundary element at the line end is absent,and the single-ended protections used in line commutated converter(LCC)based HVDC(LCC-HVDC)systems or VSC-HVDC systems cannot distinguish the fault line in multi-terminal hybrid HVDC systems.This paper proposes a novel singleended DC protection strategy suitable for the multi-terminal hybrid HVDC system,which mainly applies the transient information and active injection concept to detect and distinguish the fault line.Compared with the single-ended protections used in LCC-HVDC and VSC-HVDC systems,the proposed protection strategy is not dependent on the line boundary element and is thus suitable for the multiterminal hybrid HVDC system.The corresponding simulation cases based on power systems computer aided design(PSCAD)/electromagnetic transients including DC(EMTDC)are carried out to verify the superiority of the proposed protection.
基金National Social Science Fund of China,No.19ZDA096National Natural Science Foundation of China,No.41971234,No.41971235+1 种基金Postgraduate Research and Practice Innovation Project of Jiangsu Province,No.KYCX21_0039Open Fund of Key Laboratory of Coastal Zone Exploitation and Protection,Ministry of Natural Resources,No.2021CZEPK07。
文摘As the world’s largest developing country,the ability of China’s agricultural resource utilization to effectively support the current and future food security goals has been affected by a variety of factors(e.g.,transformed supply channels,tightening international situation and frequent emergencies)in recent years and has attracted extensive attention from the academic community subject to multiple factors.This study uses literature review,statistical analysis,and spatial analysis methods to systematically explore China’s food security situation in the context of farmland resource constraints.It is found that the demand-side pressures such as demographic changes,social class differentiation,and dietary structure adjustments derived from economic growth and rapid urbanization have placed extremely high expectations on food supply.However,the quantitative restrictions,utilization ways,and health risks of farmland resources on the supply side constitute a huge hidden concern that affects the stability of food production.Although China’s farmland protection system is undergoing a transition from focusing on quantity management to sustainable use,the matching and coordinating demand pressure and supply capacity for food security is unbalanced.Therefore,facing uncertain future development scenarios,policymakers should focus on building a resilient space for China’s farmland protection to withstand the interference of major emergencies.The existing farmland protection space policy can be integrated by establishing a national farmland strategic reserve system(based on resilient space),and further development of targeted use control measures for zoning,grading,and classification will help realize sustainable China’s farmland resources use.
基金financially supported by the National Natural Science Foundation of China(Nos.U1706225,42006046,2019GGX102014,2019YFC0312103)the Research Fund of Open Studio for Marine Corrosion and Protection,Pilot National Laboratory for Marine Science and Technology(Qingdao,No.HYFSKF201804)。
文摘A Ag@CuFe_(2)O_(4)@TiO_(2) nanocomposite film with high performance of photogenerated cathodic protection was prepared by hydrothermal and photoreduction methods.The results showed that when the CuFe_(2)O_(4) hydrothermal reaction time was 6 h and the AgNO_(3) concentration was 0.1 M,the Ag@CuFe_(2)O_(4)@TiO_(2) nanocomposite material performed the best cathodic protection capability for 304 stainless steel(304SS).In this case,the protective potential achieved-930 mV(versus SCE)associated with the photocurrent density of 475μA/cm^(2),which was 14.8 times that of pure TiO_(2) nanowires.In the dark,the nanocomposite provided cathodic protection of up to 485 mV for 304SS.Due to the heterogeneous junctions at the two interfaces among the three kinds of nanocomposite materials,the build-in electric field was fabricated,which promoted the separation efficiency of photogenerated electrons and holes and effectively improved the photochemical cathodic protection of 304SS.
基金financially supported by the National Natural Science Foundation of China(No.41827805)Chinese Academy of Engineering(No.2019-XZ-21)。
文摘In this work,TiO_(2)nanotube arrays(NTAs)sensitized with MoS_(2)microspheres(MoS_(2)/TiO_(2)nanocomposites)were prepared on a flat Ti substrate via two-step anodization and hydrothermal method sequentially.TiO_(2)NTAs were composed of many orderly nanotubes,whose large specific surface area was favorable for light absorption and MoS_(2)microsphere adhesion.The MoS_(2)microsphere as a narrow band gap semiconductor extended the TiO_(2)NTAs’absorption band edge to the visible region.The 2D structure of MoS_(2)microspheres and the construction of heterojunction electronic field at the interface of MoS_(2)microspheres and TiO_(2)NTAs promoted the separation of photoinduced carriers.The MoS_(2)/TiO_(2)nanocomposites could provide higher photoelectrochemical cathodic protection for 304 stainless steel(304 SS)under visible light than pristine TiO_(2)NTAs.
基金the CAS Strategic Priority Project(No.XDA13040404)the National Natural Science Foundation of China for Exploring Key Scientific Instrument(No.41827805)the Shandong Key Laboratory of Corrosion Science。
文摘Corrosion protection has become an important issue as the amount of infrastructure construction in marine environment increased.Photocathodic protection is a promising method to reduce the corrosion of metals,and titanium dioxide(TiO2) is the most widely used photoanode.This review summarizes the progress in TiO2 photo gene rated protection in recent years.Different types of semiconductors,including sulfides,metals,metal oxide s,polymers,and other materials,are used to design and modify TiO2.The strategy to dramatically improve the efficiency of photoactivity is proposed,and the mechanism is investigated in detail.Characterization methods are also introduced,including morphology testing,light absorption,photoelectrochemistry,and protected metal observation.This review aims to provide a comprehensive overview of Ti02 development and guide photocathodic protection.
基金National Key R&D Program of China,No.2017YFC0506506,No.2016YFC0500206National Natural Science Foundation of China,No.41501484
文摘Ecosystem services have become one of the core elements of ecosystem management and evaluation. As a key area of ecosystem services and for maintaining national ecological security, ecosystem changes and implementation effect evaluation are important in national key ecological function zones, for promoting the main function zone strategy and for improving the construction of an ecological civilization. This article studies the ecological zone of a tropical rainforest region in the central mountain area of Hainan Island, China. Multi-source satellite data and ground observation statistics are analyzed with geo-statistics method and ecological assessment model. The core analysis of this paper includes ecosystem patterns, quality and services. By means of spatial and temporal scale expansion and multidimensional space-time correlation analysis, the trends and stability characteristics of ecosystem changes are analyzed, and implementation effect evaluation is discussed. The analysis shows a variety of results. The proportion of forest area inside the ecological zone was significantly higher than the average level in Hainan Island. During 1990–2013, settlement gradually increased inside the ecological zone. After implementation of the zone in 2010, human activity intensity increased, with the main land use being urban construction and land reclamation. Water conservation in the ecological function zone was higher than that outside the zone. In general, it increased slightly, but had obvious fluctuations. Soil conservation inside the zone was also better than that outside. However, it demonstrated dramatic fluctuations and relatively poor stability during 1990–2013. The human disturbance index inside the zone was significantly lower than that outside, and had a lower biodiversity threat level. Especially in 2010–2013, the increased range of the human disturbance index inside the zone was significantly less than that outside.
文摘Taking lightning-protection engineering of Wuhan Changshankou landfill and incineration plants for the example,in this article,we have discussed the integrated technology of direct lightning protection by early streamer emission lightning rod,lifting lightning rod and mobile lightning rod. Additionally,lightning protection methods and measures of landfill with large receiving area of lightning strike and landfill gas and incineration plant with irregular landfill cell are explored.
文摘As we have borrowed the wisdom from biological neural network, the characteristic of interference- proof in information transferring process has been carefully studied. Our study includes the response of electrical-interference-proof circuit in electromagnetic environment, by means of bionics redesign. In this way, new principles, new technics and new ways are adopted to solve the unavoidable situations in traditional electro- magnet protection design. Based on the Boolean model, the complex bionic topological networks were firstly built and the charactoristics of degeneracy were analyzed, then the bidirectional actions between degeneracy in networks and the robustness of functions were proved in order to fill up the gap to deal with the need of interference-proof. Based on the creation of the neuron networks and the electrical synapses ' charac- teristic of plasticity, the impact of the distribution in the weight of synapse on the character of network self- recovery was studied afterwards so that the corresponding mechanism could be defined.
文摘Via database technology, a perfect lightning protection integrated service work platform is established, thereby realizing paperless data management of routine business.
文摘Huadianba in the Cangshan Mountain, a region where key ecosystem types and species under prior protection are concentrated, is the first choice for the comprehensive protection and development of biodiversity. In this study, natural conditions, location and current protection and development of Huadianba were introduced, major problems emerging in the protection and management were summarized, and pertinent measures were proposed as a reference for the scientific development and protection of Huadianba.
基金financially supported by the Young Elite Scientists Sponsorship Program by the China Association for Science and Technology(YESS,No.2020QNRC001)the National Science and Technology Resources Investigation Program of China(No.2021FY100603)the Fundamental Research Funds for the Central Universities(No.FRF-BD-20-28A2)。
文摘Metal corrosion causes significant economic losses,safety issues,and environmental pollution.Hence,its prevention is of immense research interest.Carbon dots(CDs)are a new class of zero-dimensional carbon nanomaterials,which have been considered for corrosion protection applications in recent years due to their corrosion inhibition effect,fluorescence,low toxicity,facile chemical modification,and cost-effectiveness.This study provides a comprehensive overview of the synthesis,physical and chemical properties,and anticorrosion mechanisms of functionalized CDs.First,the corrosion inhibition performance of different types of CDs is introduced,followed by discussion on their application in the development of smart protective coatings with self-healing and/or self-reporting properties.The effective barrier formed by CDs in the coatings can inhibit the spread of local damage and achieve self-healing behavior.In addition,diverse functional groups on CDs can interact with Fe^(3+)and H^(+)ions generated during the corrosion process;this interaction changes their fluorescence,thereby demonstrating self-reporting behavior.Moreover,challenges and prospects for the development of CD-based corrosion protection systems are also presented.
基金financially supported by the National Natural Science Foundation of China(No.41976036)the State Key Laboratory for Marine Corrosion and Protection,Luoyang Ship Material Research Institute(LSMRI)(Nos.KF190408 and KF190404)。
文摘A novel three-dimensional hierarchical WO_(3)photoelectrode was prepared by solvothermal method,and ZnO was deposited on its surface by electrochemical method.The WO_(3)/ZnWO_(4)/ZnO multiphaseheterojunction photoelectrode was prepared by further annealing treatment to explore the photoinduced cathodic protection(CP)performance.Compared with WO_(3)and ZnO,the photoinduced CP and electron storage capacity performance of WO_(3)/ZnWO_(4)/ZnO is significantly improved in 3.5%NaCl solution without adding any hole scavenger.The electron storage capacity of the WO_(3)/ZnWO_(4)/ZnO heterojunction makes it possible to continuously protect metallic materials in the dark after switching off the light,which can realize long-term and effective photoinduced CP.
基金supported by the National Natural Science Foundation of China(Nos.42106051,U2106206,U1706225,42006046,2019YFC0312103)。
文摘Semiconductor quantum dots with high quantum yield and photovoltaic conversion efficiency have ushered in a brilliant moment for constructing internal electric field heterojunctions for photogenerated cathodic protection applications.In this paper,TiO_(2)nanotubes grown vertically on the surface of titanium substrates were modified via a combination of conventional electrochemical oxidation and a one-step solvothermal pathway to sensitize with CuInS_(2)quantum dots.Compared with pure TiO_(2)photoelectrodes,the modification improves sunlight absorption efficiency and provides photoelectron cathodic protection to the 304 stainless steel(304 SS).Through 9 h solvothermal reaction,the CuInS_(2)/TiO_(2)coupled with protected 304 SS exhibited an excellent property when the simulated sunlight irradiation.Its mixed open circuit potential is negatively shifted to-0.99 V,at the mean time with a stable photocurrent density(118μA cm^(-2)).The results indicate that CuInS_(2)and TiO_(2)established a p-n heterojunction with wellmatched energy level,which can effectively facilitate the carrier separation and retain the strong redox capbility of photo-induced electrons and holes.