Nearly all real-world networks are complex networks and usually are in danger of collapse.Therefore,it is crucial to exploit and understand the mechanisms of network attacks and provide better protection for network f...Nearly all real-world networks are complex networks and usually are in danger of collapse.Therefore,it is crucial to exploit and understand the mechanisms of network attacks and provide better protection for network functionalities.Network dismantling aims to find the smallest set of nodes such that after their removal the network is broken into connected components of sub-extensive size.To overcome the limitations and drawbacks of existing network dismantling methods,this paper focuses on network dismantling problem and proposes a neighbor-loop structure based centrality metric,NL,which achieves a balance between computational efficiency and evaluation accuracy.In addition,we design a novel method combining NL-based nodes-removing,greedy tree-breaking and reinsertion.Moreover,we compare five baseline methods with our algorithm on ten widely used real-world networks and three types of model networks including Erd€os-Renyi random networks,Watts-Strogatz smallworld networks and Barabasi-Albert scale-free networks with different network generation parameters.Experimental results demonstrate that our proposed method outperforms most peer methods by obtaining a minimal set of targeted attack nodes.Furthermore,the insights gained from this study may be of assistance to future practical research into real-world networks.展开更多
Based on the existing plant layout and process flow,a simulation analysis was conducted using the Plant Simulation platform with the utilization efficiency of each station and production capacity of the dismantling sy...Based on the existing plant layout and process flow,a simulation analysis was conducted using the Plant Simulation platform with the utilization efficiency of each station and production capacity of the dismantling system as indicators.A problem with long-term suspension in the disassembly process was determined.Based on the two optimization directions of increasing material transportation equipment and expanding the buffer capacity,a cost-oriented optimization model is established.A genetic algorithm and model simulation were used to solve the model.An optimization scheme that satisfies the production needs and has the lowest cost is proposed.The results show that the optimized dismantling system solves the suspended work problem at the dismantling station and a significant improvement in productivity and station utilization efficiency compared with the previous system.展开更多
Objective To study the effects of environmental multi-media lead pollution on blood lead and sex hormone levels among lead exposed males engaged in E-waste dismantling, and the correlation between confounding factors ...Objective To study the effects of environmental multi-media lead pollution on blood lead and sex hormone levels among lead exposed males engaged in E-waste dismantling, and the correlation between confounding factors and sex hormone levels. Methods An E-waste dismantling area in Taizhou of Zhejiang Province was selected as the research site. One hundred and fifty two samples were collected from the groundwater, soil, rice, corn, chicken, and pork in the dismantling area. The effects of the multi-media lead pollution on the male blood lead and sex hormone levels of FSH, LH, and T, as well as the correlation with confounding factors, were studied. Results The blood lead concentrations in the males aged under 31, from 31 to 45 and from 46 to 60 were 98.55, 100.23, and 101.45 I~/L, respectively. Of all the environmental media lead exposures, the groundwater, rice and soil were main contributing factors to the lead accumulation in humans. FSH and LH levels increased with the age while the T levels decreased with the age instead. There was a significant correlation between the FSH and LH levels and wearing masks. Conclusion There was correlation between the FSH, LH, and T levels, and the mean values of lead concentrations in environmental media, and the sex hormone levels were correlated with the confounding factor of wearing masks.展开更多
Soil is an essential resource for agricultural production.In order to investigate the pollution situation of heavy metals in the soil-crop system in the e-waste dismantling area,the crop and soil samples(226 pairs,inc...Soil is an essential resource for agricultural production.In order to investigate the pollution situation of heavy metals in the soil-crop system in the e-waste dismantling area,the crop and soil samples(226 pairs,including leaf vegetables,solanaceous vegetables,root vegetables,and fruits)around the e-waste dismantling area in southeastern Zhejiang Province were collected.The concentrations of Cd,Cu,Pb,and Cr were determined.The average concentrations of Cd,Cu,Pb,and Cr in soils were 0.94,107.79,80.28,and 78.14 mg kg-1,respectively,and their corresponding concentrations in crops were 0.024,0.7,0.041,and 0.06 mg kg-1,respectively.The transfer capacity of leaf vegetables was significantly higher than that of non-leaf vegetables,and the accumulation of four heavy metals in crops tended to be Cd>Cu>Cr/Pb.The pollution index’s results revealed that the soil pollution degree under different land uses ranked as root vegetables soil>leaf vegetables soil>solanaceous vegetables soil>fruit soil.The carcinogenic and non-carcinogenic risks of heavy metal exposure were ranked as food intake>accidental ingestion>dermal contact>inhalation.The comprehensive non-carcinogenic risk was ranked as Cr>Cd>Pb/Cu.Our results could be used to provide useful information for further crop cultivation layout in the study area,which can guarantee the local residents’health and food safety.展开更多
Background:The Hair-crested Drongo(Dicrurus hottentottus) exhibits a unique nest-dismantling behavior after the fledging of the young.One hypothesis explaining this behavior is dismantling one's own nest may reduc...Background:The Hair-crested Drongo(Dicrurus hottentottus) exhibits a unique nest-dismantling behavior after the fledging of the young.One hypothesis explaining this behavior is dismantling one's own nest may reduce potential competition for nest sites in the following breeding season because suitable breeding habitat might be limited,and sites are often reused.Methods:By comparing the habitat features at nest and random locations,we determined the nest habitat preference of the Hair-crested Drongo within Dongzhai National Nature Reserve,Henan,China.We also compared habitat features with nesting success to determine if any trends could be detected.Results:We found that nest tree height,diameter at breast height,live crown ratio,tree rank,and presence of overstory were significantly higher at nesting locations than random locations;slope,leaf litter cover percentage and depth,presence of understory and midstory,and number of trees per hectare were significantly lower at nest sites than random sites.Drongos preferred to use some tree species,such as Metasequoia glyptostroboides,Castanea mollissima,and Pterocarya stenoptera for nesting.Failed nests were often associated with habitat with higher percentage of leaf litter on the ground.Conclusion:Our data support that selection of nest sites does occur for this species at this site and therefore support the hypothesis that breeding habitat limitation could be one of the driving forces for the development of the nestdismantling behavior in this species.展开更多
Fuel cycle related activities were accomplished in IPEN-CNEN/SP in laboratory and pilot plant scale and most facilities were built in the 70-80 years. Nevertheless, radical changes of the Brazilian nuclear policy in t...Fuel cycle related activities were accomplished in IPEN-CNEN/SP in laboratory and pilot plant scale and most facilities were built in the 70-80 years. Nevertheless, radical changes of the Brazilian nuclear policy in the beginning of 90's determined the interruption of several fuel cycle activities and facilities shutdown. Some laboratory and pilot plant decommissioning activities have been performed in IPEN in the last years. During the operational activities in the decommissioning of old nuclear fuel cycle facilities, the personnel involved in the task had to face several problems. In old facilities, the need of large components dismantling and material removal use to present some difficulties, such as lack of available and near electricity supply. Besides this, the spread out of the superficial contamination in the form of dust or aerosols and the exposure of workers should be as much as possible avoided. Then, the selection and availability of suitable tools for the task, mainly those employed for cutting and segmentation of different materials is of significant importance. Slight hand tools, mainly those powered by rechargeable batteries, facilitate the work, especially in areas where the access is difficult. Based on the experience in the dismantling of some old nuclear facilities of IPEN-CNEN/SP, some tools that would have facilitated the operations were identified and their availability could have improved the quality and efficiency of different individual tasks. In this paper, different cutting problems and techniques, as well as some available commercial hand tools, are presented as suggestion for future activities.展开更多
We describe the case of a patient presenting with STsegment elevation myocardial infarction due to very late scaffold thrombosis. The patient was already admitted for an elective percutaneous recanalization of a chron...We describe the case of a patient presenting with STsegment elevation myocardial infarction due to very late scaffold thrombosis. The patient was already admitted for an elective percutaneous recanalization of a chronically occluded left anterior descending artery(LAD). The procedure was performed according the subintimal tracking and re-entry(STAR) technique with 4 bioresorbable vascular scaffolds implantation. However, even though the coronary flow was preserved at the end of the procedure, the dissected segment was only partially sealed at the distal segment of the LAD. After 18 mo of regular assumption, dual antiplatelet therapy was discontinued for 10 mo before his presentation at the emergency room. This is the first reported case of a very late scaffold thrombosis after coronary chronic total occlusion(CTO) recanalization performed according to the STAR technique. This case raises concerns about the risk of very late scaffold thrombosis after complex CTO revascularization.展开更多
From beginning of 90's, the Brazilian nuclear policy has been changed radically. This determined the interruption of most R&D fuel cycle activities and the facilities shutdown at Nuclear and Energetic Research Insti...From beginning of 90's, the Brazilian nuclear policy has been changed radically. This determined the interruption of most R&D fuel cycle activities and the facilities shutdown at Nuclear and Energetic Research Institute (IPEN). The existence of those facilities also implicated in the need of constant surveillance, representing additional obligations, costs and problems. The reasons to promote the dismantling of the IPEN's Nuclear Fuel Cycle Pilot Plants elapsed mainly from the need of physical space for new activities, since the R&D in the nuclear fuel cycle area were interrupted. In the last decade, IPEN has changed its "nuclear profile" to a "comprehensive and multidisciplinary profile". With the end of most nuclear fuel cycle activities, the former facilities were distributed in four different centers. Each center has adopted a different strategy and priority to face the D&D problem. The available resources depend on the specific program in each area's development (resources available from other sources, not only from Brazilian National Nuclear Energy Commission (CNEN). One of those new activities is the IPEN's Environmental Program. This paper describes the procedures, problems faced and results related to the reintegration of the former pilot plant areas as new laboratories of the Chemical and Environmental Technology Center-CQMA of the IPEN.展开更多
The dismantling and recycling of junction boxes,which is an important part of the photovoltaic module recycling process,was tested and designed scientifically.The equipment framework was built by three-dimensional sim...The dismantling and recycling of junction boxes,which is an important part of the photovoltaic module recycling process,was tested and designed scientifically.The equipment framework was built by three-dimensional simulation,and then the design of dismantling and recycling equipment for junction boxes of waste crystal silicon photovoltaic modules was completed through the experimental test and data analysis.The experimental results show that the initial idea of the dismantling scheme is correct,and the structure is feasible.However,some problems were not considered.This study provides reliable data support for the subsequent equipment development and ensures the smooth development of the subsequent design work.展开更多
One million Chinese villages have disappeared in the three decades since the beginning of China's rural reform, one third of the total. As a result of this urbanization, China can no longer produce enough grain for i...One million Chinese villages have disappeared in the three decades since the beginning of China's rural reform, one third of the total. As a result of this urbanization, China can no longer produce enough grain for itself. In 2012, China imported 80 million tons of grain, which is about 12% of its total grain need. Now the new Chinese Government inaugurated in 2013 has stepped up its push for more urbanization. Many more rural villages throughout China have been dismantled or will be dismantled at a crazy pace. China's environmental degradation will surely further deteriorate. This paper is a case study about urbanization and its social, economic, and environmental consequences in China.展开更多
Supply chain finance has played a positive role in solving the financing difficulties of small and medium-sized enterprises.However,in the actual implementation process,there are still problems such as information asy...Supply chain finance has played a positive role in solving the financing difficulties of small and medium-sized enterprises.However,in the actual implementation process,there are still problems such as information asymmetry,doubts about the authenticity of trade background,and high operational risks,which seriously restrict the development of supply chain finance.However,block chain technology has the characteristics of de-centralization,data transparency,common maintenance and non-tampering.Applying this technology to supply chain finance can effectively solve the existing problems.Based on the research on the development status of traditional supply chain finance,this paper puts forward a new development mode of supply chain finance based on block chain technology,and through the analysis of typical cases,finally gives some policy suggestions for the development of block chain supply chain finance.展开更多
The decommissioning of nuclear power plants is in the Slovak Republic an actual issue. In 2015 started the second decommissioning stage of nuclear power plant V1 in Jaslovské Bohunice. This stage involves the dis...The decommissioning of nuclear power plants is in the Slovak Republic an actual issue. In 2015 started the second decommissioning stage of nuclear power plant V1 in Jaslovské Bohunice. This stage involves the dismantling and segmentation of activated (reactor pressure vessel, reactor internals) and contaminated parts (steam generators, pressurizer). From this reason it is necessary to investigate the radiation situation in the vicinity of the component to be cut. The presented results show that during remote dismantling the exposure is small (compared with the fragmentation tasks). Moreover, when the pre-dismantling decontamination with decontamination factor of 100 is applied, the total collective effective dose is below the yearly limit of 20 mSv for workers.展开更多
DENG Ouya, a Chinese Canadian who works as an IT engineer in Montreal, has nurtured an en- thusiasm for cars since he was a student. "1 bought my Mercedes-Benz GLK 350 at the price of 50,000 Canadian dollars ($45.80...DENG Ouya, a Chinese Canadian who works as an IT engineer in Montreal, has nurtured an en- thusiasm for cars since he was a student. "1 bought my Mercedes-Benz GLK 350 at the price of 50,000 Canadian dollars ($45.800) when migrating to Canada, but the price for the same model assem- bled in China is 450,000 yuan ($73,100) or so in the Chinese market," Deng told ChinAfrica, Moreover, the prices of auto parts can be as astoundingly expensive as those of finished cars in the Chinese market. This inequality largely owes to the monopolistic position of foreign carmakers.展开更多
Miss Bernat comes to Mr. Wang’s booth on the last day of exhibition. She expresses her appreciation of Mr. Wang’s products. At the same time, gives her own suggestions.
Deconstruction is the selective dismantling of building structures to recover the maximum amount of primarily reusable and secondarily recyclable materials in a safe and cost-effective manner.Deconstruction is a labor...Deconstruction is the selective dismantling of building structures to recover the maximum amount of primarily reusable and secondarily recyclable materials in a safe and cost-effective manner.Deconstruction is a labor intensive process and can be difficult to achieve in a time-efficient and economical manner for light wood-framed buildings.Deconstruction techniques that balance hand and mechanical labor must be developed to maintain the integrity of materials for reuse and obtain maximum salvage value per unit of cost and time-on-site.This project entailed the removal of three identical WWII-era two-story wood-framed barracks buildings at Ft.McClellan Army Base,Anniston,AL,using hand deconstruction,combined mechanical and hand deconstruction techniques,and a traditional demolition method,i.e.,mechanical reduction and disposal,in order to determine“optimal”deconstruction techniques based on salvage value per unit of cost.The maximum practical materials salvage from the study buildings using 100%hand deconstruction techniques was 39%of the mass by weight.A combination of hand and mechanical techniques was discovered to have approximately the same economic efficiency as 100%hand deconstruction,measured as a ratio of gross cost per salvage value,with a 44.6%reduction in total labor-hours,and a reduction of only 7%of salvage materials by weight.These findings indicate the potential for greatly increasing wood-framed building deconstruction practice relative to the additional time-on-site and labor that is required,compared to demolition,while optimizing economic benefits.This paper describes the research methods and deconstruction techniques employed,and lessons learned to advance the practice of deconstruction to be more economically competitive and time-efficient.展开更多
Solar energy is currently one of the most promising clean energy sources and the use of solar energy has led to a rapid increase in the number of solar cells.As one of the fastest-growing electronic wastes,the resourc...Solar energy is currently one of the most promising clean energy sources and the use of solar energy has led to a rapid increase in the number of solar cells.As one of the fastest-growing electronic wastes,the resource treatment of solar cells at the end of their life should not be neglected.This review discusses the trend for the market development of crystalline-silicon solar cells and analyzes their physical structure and composition.It also discusses the current domestic and international recycling technologies for crystalline-silicon solar cells,including manual dismantling,inorganic acid dissolution,the combination of heat-treatment and chemical methods,and organic solvent dissolution.The shortcomings of the above treatment methods are discussed and some views on the recycling of waste crystalline-silicon solar cells are presented.Constructive suggestions for the green and sustainable development of crystalline-silicon solar cells are put forward by comparing different treatment-recycling processes.展开更多
The network dismantling problem asks the minimum separate node set of a graph whose removal will break the graph into connected components with the size not larger than the one percentage of the original graph.This pr...The network dismantling problem asks the minimum separate node set of a graph whose removal will break the graph into connected components with the size not larger than the one percentage of the original graph.This problem has attracted much attention recently and a lot of algorithms have been proposed. However, most of the network dismantling algorithms mainly focus on which nodes are included in the minimum separate set but overlook how to order them for removal, which will lead to low general efficiency during the dismantling process. In this paper,we reformulate the network dismantling problem by taking the order of nodes’ removal into consideration. An efficient dismantling sequence will break the network quickly during the dismantling processes. We take the belief-propagation guided decimation(BPD) dismantling algorithm, a state-of-the-art algorithm, as an example, and employ the node explosive percolation(NEP) algorithm to reorder the early part of the dismantling sequence given by the BPD. The proposed method is denoted as the NEP-BPD algorithm(NBA) here. The numerical results on Erd¨os-R′enyi graphs,random-regular graphs, scale-free graphs, and some real networks show the high general efficiency of NBA during the entire dismantling process. In addition, numerical computations on random graph ensembles with the size from 210 to219 exhibit that the NBA is in the same complexity class with the BPD algorithm. It is clear that the NEP method we used to improve the general efficiency could also be applied to other dismantling algorithms, such as Min-Sum algorithm,equal graph partitioning algorithm and so on.展开更多
Atmospheric concentrations of Dechlorane Plus(DP)were investigated in Taizhou,an electronic-waste(E-waste)dismantling region in East China.Passive air samplers with polyurethane foam(PUF)disks were deployed every thre...Atmospheric concentrations of Dechlorane Plus(DP)were investigated in Taizhou,an electronic-waste(E-waste)dismantling region in East China.Passive air samplers with polyurethane foam(PUF)disks were deployed every three months during the sampling period of September 2009-August 2010.The total DP(syn-and anti-DP)concentrations in air ranged from not detected to 277 pg/m^3,with a mean concentration of 53.9 pg/m^3.A generally declining trend of DP levels was found from the E-waste dismantling region to the peripheral areas.The median values of total DP concentrations in autumn,winter,spring and summer were 52.2,28.8,39.7 and 30.1 pg/m^3,respectively.The seasonal variations of DP concentrations were mainly associated with the intensity of E-waste dismantling activities and meteorological conditions.The mean value of anti-DP fractional abundance(f_(anti))was 0.74±0.08,which was consistent with those in the commercial DP products.This study confirmed a significant emission source related to the distribution of atmospheric DP in the E-waste dismantling area and supplied information for the seasonal variation of DP in the atmosphere.展开更多
The 34th meeting of the 18th Central Leading Group on Deepening Reform adopted the Implementation Plan on Banning the Entry of Foreign Waste and Promoting the Reform of Solid Waste Import Management System in April 20...The 34th meeting of the 18th Central Leading Group on Deepening Reform adopted the Implementation Plan on Banning the Entry of Foreign Waste and Promoting the Reform of Solid Waste Import Management System in April 2017,and decided to phase out the import of solid waste by 2019.In April 2018,the Ministry of Ecological Environment.展开更多
基金the National Natural Science Foundation of China under Grants 61871209 and 61901210,in part by Artificial Intelligence and Intelligent Transportation Joint Technical Center of HUST and Hubei Chutian Intelligent Transportation Co.,LTD under project”Intelligent Transportation Operation Monitoring Network and System”.
文摘Nearly all real-world networks are complex networks and usually are in danger of collapse.Therefore,it is crucial to exploit and understand the mechanisms of network attacks and provide better protection for network functionalities.Network dismantling aims to find the smallest set of nodes such that after their removal the network is broken into connected components of sub-extensive size.To overcome the limitations and drawbacks of existing network dismantling methods,this paper focuses on network dismantling problem and proposes a neighbor-loop structure based centrality metric,NL,which achieves a balance between computational efficiency and evaluation accuracy.In addition,we design a novel method combining NL-based nodes-removing,greedy tree-breaking and reinsertion.Moreover,we compare five baseline methods with our algorithm on ten widely used real-world networks and three types of model networks including Erd€os-Renyi random networks,Watts-Strogatz smallworld networks and Barabasi-Albert scale-free networks with different network generation parameters.Experimental results demonstrate that our proposed method outperforms most peer methods by obtaining a minimal set of targeted attack nodes.Furthermore,the insights gained from this study may be of assistance to future practical research into real-world networks.
基金the Research on Key Technology of Dismantling Railway Scrap Freight Cars,No.W2021JSFW0236.
文摘Based on the existing plant layout and process flow,a simulation analysis was conducted using the Plant Simulation platform with the utilization efficiency of each station and production capacity of the dismantling system as indicators.A problem with long-term suspension in the disassembly process was determined.Based on the two optimization directions of increasing material transportation equipment and expanding the buffer capacity,a cost-oriented optimization model is established.A genetic algorithm and model simulation were used to solve the model.An optimization scheme that satisfies the production needs and has the lowest cost is proposed.The results show that the optimized dismantling system solves the suspended work problem at the dismantling station and a significant improvement in productivity and station utilization efficiency compared with the previous system.
基金supported by the National Natural Science Foundation of China (No.21177119)the Ministry of Environmental Protection Funded Project (No.200909101)the National Natural Science Foundation of China(21007005)
文摘Objective To study the effects of environmental multi-media lead pollution on blood lead and sex hormone levels among lead exposed males engaged in E-waste dismantling, and the correlation between confounding factors and sex hormone levels. Methods An E-waste dismantling area in Taizhou of Zhejiang Province was selected as the research site. One hundred and fifty two samples were collected from the groundwater, soil, rice, corn, chicken, and pork in the dismantling area. The effects of the multi-media lead pollution on the male blood lead and sex hormone levels of FSH, LH, and T, as well as the correlation with confounding factors, were studied. Results The blood lead concentrations in the males aged under 31, from 31 to 45 and from 46 to 60 were 98.55, 100.23, and 101.45 I~/L, respectively. Of all the environmental media lead exposures, the groundwater, rice and soil were main contributing factors to the lead accumulation in humans. FSH and LH levels increased with the age while the T levels decreased with the age instead. There was a significant correlation between the FSH and LH levels and wearing masks. Conclusion There was correlation between the FSH, LH, and T levels, and the mean values of lead concentrations in environmental media, and the sex hormone levels were correlated with the confounding factor of wearing masks.
基金supported by the National College Students’Innovation and Entrepreneurship Training Program(202110341014).
文摘Soil is an essential resource for agricultural production.In order to investigate the pollution situation of heavy metals in the soil-crop system in the e-waste dismantling area,the crop and soil samples(226 pairs,including leaf vegetables,solanaceous vegetables,root vegetables,and fruits)around the e-waste dismantling area in southeastern Zhejiang Province were collected.The concentrations of Cd,Cu,Pb,and Cr were determined.The average concentrations of Cd,Cu,Pb,and Cr in soils were 0.94,107.79,80.28,and 78.14 mg kg-1,respectively,and their corresponding concentrations in crops were 0.024,0.7,0.041,and 0.06 mg kg-1,respectively.The transfer capacity of leaf vegetables was significantly higher than that of non-leaf vegetables,and the accumulation of four heavy metals in crops tended to be Cd>Cu>Cr/Pb.The pollution index’s results revealed that the soil pollution degree under different land uses ranked as root vegetables soil>leaf vegetables soil>solanaceous vegetables soil>fruit soil.The carcinogenic and non-carcinogenic risks of heavy metal exposure were ranked as food intake>accidental ingestion>dermal contact>inhalation.The comprehensive non-carcinogenic risk was ranked as Cr>Cd>Pb/Cu.Our results could be used to provide useful information for further crop cultivation layout in the study area,which can guarantee the local residents’health and food safety.
基金support by Dongzhai National Nature Reserve for conducting this studyFunding and support was provided by National Science Foundation East Asia Pacific Summer Institute (EAPSI)+2 种基金Chinese Ministry of Science and TechnologyChina Science and Technology Exchange Center Further funding and support was provided by Alabama A&M University and Beijing Normal University
文摘Background:The Hair-crested Drongo(Dicrurus hottentottus) exhibits a unique nest-dismantling behavior after the fledging of the young.One hypothesis explaining this behavior is dismantling one's own nest may reduce potential competition for nest sites in the following breeding season because suitable breeding habitat might be limited,and sites are often reused.Methods:By comparing the habitat features at nest and random locations,we determined the nest habitat preference of the Hair-crested Drongo within Dongzhai National Nature Reserve,Henan,China.We also compared habitat features with nesting success to determine if any trends could be detected.Results:We found that nest tree height,diameter at breast height,live crown ratio,tree rank,and presence of overstory were significantly higher at nesting locations than random locations;slope,leaf litter cover percentage and depth,presence of understory and midstory,and number of trees per hectare were significantly lower at nest sites than random sites.Drongos preferred to use some tree species,such as Metasequoia glyptostroboides,Castanea mollissima,and Pterocarya stenoptera for nesting.Failed nests were often associated with habitat with higher percentage of leaf litter on the ground.Conclusion:Our data support that selection of nest sites does occur for this species at this site and therefore support the hypothesis that breeding habitat limitation could be one of the driving forces for the development of the nestdismantling behavior in this species.
文摘Fuel cycle related activities were accomplished in IPEN-CNEN/SP in laboratory and pilot plant scale and most facilities were built in the 70-80 years. Nevertheless, radical changes of the Brazilian nuclear policy in the beginning of 90's determined the interruption of several fuel cycle activities and facilities shutdown. Some laboratory and pilot plant decommissioning activities have been performed in IPEN in the last years. During the operational activities in the decommissioning of old nuclear fuel cycle facilities, the personnel involved in the task had to face several problems. In old facilities, the need of large components dismantling and material removal use to present some difficulties, such as lack of available and near electricity supply. Besides this, the spread out of the superficial contamination in the form of dust or aerosols and the exposure of workers should be as much as possible avoided. Then, the selection and availability of suitable tools for the task, mainly those employed for cutting and segmentation of different materials is of significant importance. Slight hand tools, mainly those powered by rechargeable batteries, facilitate the work, especially in areas where the access is difficult. Based on the experience in the dismantling of some old nuclear facilities of IPEN-CNEN/SP, some tools that would have facilitated the operations were identified and their availability could have improved the quality and efficiency of different individual tasks. In this paper, different cutting problems and techniques, as well as some available commercial hand tools, are presented as suggestion for future activities.
文摘We describe the case of a patient presenting with STsegment elevation myocardial infarction due to very late scaffold thrombosis. The patient was already admitted for an elective percutaneous recanalization of a chronically occluded left anterior descending artery(LAD). The procedure was performed according the subintimal tracking and re-entry(STAR) technique with 4 bioresorbable vascular scaffolds implantation. However, even though the coronary flow was preserved at the end of the procedure, the dissected segment was only partially sealed at the distal segment of the LAD. After 18 mo of regular assumption, dual antiplatelet therapy was discontinued for 10 mo before his presentation at the emergency room. This is the first reported case of a very late scaffold thrombosis after coronary chronic total occlusion(CTO) recanalization performed according to the STAR technique. This case raises concerns about the risk of very late scaffold thrombosis after complex CTO revascularization.
文摘From beginning of 90's, the Brazilian nuclear policy has been changed radically. This determined the interruption of most R&D fuel cycle activities and the facilities shutdown at Nuclear and Energetic Research Institute (IPEN). The existence of those facilities also implicated in the need of constant surveillance, representing additional obligations, costs and problems. The reasons to promote the dismantling of the IPEN's Nuclear Fuel Cycle Pilot Plants elapsed mainly from the need of physical space for new activities, since the R&D in the nuclear fuel cycle area were interrupted. In the last decade, IPEN has changed its "nuclear profile" to a "comprehensive and multidisciplinary profile". With the end of most nuclear fuel cycle activities, the former facilities were distributed in four different centers. Each center has adopted a different strategy and priority to face the D&D problem. The available resources depend on the specific program in each area's development (resources available from other sources, not only from Brazilian National Nuclear Energy Commission (CNEN). One of those new activities is the IPEN's Environmental Program. This paper describes the procedures, problems faced and results related to the reintegration of the former pilot plant areas as new laboratories of the Chemical and Environmental Technology Center-CQMA of the IPEN.
文摘The dismantling and recycling of junction boxes,which is an important part of the photovoltaic module recycling process,was tested and designed scientifically.The equipment framework was built by three-dimensional simulation,and then the design of dismantling and recycling equipment for junction boxes of waste crystal silicon photovoltaic modules was completed through the experimental test and data analysis.The experimental results show that the initial idea of the dismantling scheme is correct,and the structure is feasible.However,some problems were not considered.This study provides reliable data support for the subsequent equipment development and ensures the smooth development of the subsequent design work.
文摘One million Chinese villages have disappeared in the three decades since the beginning of China's rural reform, one third of the total. As a result of this urbanization, China can no longer produce enough grain for itself. In 2012, China imported 80 million tons of grain, which is about 12% of its total grain need. Now the new Chinese Government inaugurated in 2013 has stepped up its push for more urbanization. Many more rural villages throughout China have been dismantled or will be dismantled at a crazy pace. China's environmental degradation will surely further deteriorate. This paper is a case study about urbanization and its social, economic, and environmental consequences in China.
基金Shandong Key Research and Development Project(Soft Science):2019RKC20001。
文摘Supply chain finance has played a positive role in solving the financing difficulties of small and medium-sized enterprises.However,in the actual implementation process,there are still problems such as information asymmetry,doubts about the authenticity of trade background,and high operational risks,which seriously restrict the development of supply chain finance.However,block chain technology has the characteristics of de-centralization,data transparency,common maintenance and non-tampering.Applying this technology to supply chain finance can effectively solve the existing problems.Based on the research on the development status of traditional supply chain finance,this paper puts forward a new development mode of supply chain finance based on block chain technology,and through the analysis of typical cases,finally gives some policy suggestions for the development of block chain supply chain finance.
文摘The decommissioning of nuclear power plants is in the Slovak Republic an actual issue. In 2015 started the second decommissioning stage of nuclear power plant V1 in Jaslovské Bohunice. This stage involves the dismantling and segmentation of activated (reactor pressure vessel, reactor internals) and contaminated parts (steam generators, pressurizer). From this reason it is necessary to investigate the radiation situation in the vicinity of the component to be cut. The presented results show that during remote dismantling the exposure is small (compared with the fragmentation tasks). Moreover, when the pre-dismantling decontamination with decontamination factor of 100 is applied, the total collective effective dose is below the yearly limit of 20 mSv for workers.
文摘DENG Ouya, a Chinese Canadian who works as an IT engineer in Montreal, has nurtured an en- thusiasm for cars since he was a student. "1 bought my Mercedes-Benz GLK 350 at the price of 50,000 Canadian dollars ($45.800) when migrating to Canada, but the price for the same model assem- bled in China is 450,000 yuan ($73,100) or so in the Chinese market," Deng told ChinAfrica, Moreover, the prices of auto parts can be as astoundingly expensive as those of finished cars in the Chinese market. This inequality largely owes to the monopolistic position of foreign carmakers.
文摘Miss Bernat comes to Mr. Wang’s booth on the last day of exhibition. She expresses her appreciation of Mr. Wang’s products. At the same time, gives her own suggestions.
文摘Deconstruction is the selective dismantling of building structures to recover the maximum amount of primarily reusable and secondarily recyclable materials in a safe and cost-effective manner.Deconstruction is a labor intensive process and can be difficult to achieve in a time-efficient and economical manner for light wood-framed buildings.Deconstruction techniques that balance hand and mechanical labor must be developed to maintain the integrity of materials for reuse and obtain maximum salvage value per unit of cost and time-on-site.This project entailed the removal of three identical WWII-era two-story wood-framed barracks buildings at Ft.McClellan Army Base,Anniston,AL,using hand deconstruction,combined mechanical and hand deconstruction techniques,and a traditional demolition method,i.e.,mechanical reduction and disposal,in order to determine“optimal”deconstruction techniques based on salvage value per unit of cost.The maximum practical materials salvage from the study buildings using 100%hand deconstruction techniques was 39%of the mass by weight.A combination of hand and mechanical techniques was discovered to have approximately the same economic efficiency as 100%hand deconstruction,measured as a ratio of gross cost per salvage value,with a 44.6%reduction in total labor-hours,and a reduction of only 7%of salvage materials by weight.These findings indicate the potential for greatly increasing wood-framed building deconstruction practice relative to the additional time-on-site and labor that is required,compared to demolition,while optimizing economic benefits.This paper describes the research methods and deconstruction techniques employed,and lessons learned to advance the practice of deconstruction to be more economically competitive and time-efficient.
基金This work was supported by the National Key R&D Program of China(SQ2019YFC190083).
文摘Solar energy is currently one of the most promising clean energy sources and the use of solar energy has led to a rapid increase in the number of solar cells.As one of the fastest-growing electronic wastes,the resource treatment of solar cells at the end of their life should not be neglected.This review discusses the trend for the market development of crystalline-silicon solar cells and analyzes their physical structure and composition.It also discusses the current domestic and international recycling technologies for crystalline-silicon solar cells,including manual dismantling,inorganic acid dissolution,the combination of heat-treatment and chemical methods,and organic solvent dissolution.The shortcomings of the above treatment methods are discussed and some views on the recycling of waste crystalline-silicon solar cells are presented.Constructive suggestions for the green and sustainable development of crystalline-silicon solar cells are put forward by comparing different treatment-recycling processes.
基金Supported by the 2016 Basic Operational Outlays for the Research Activities of Centric University,Civil Aviation University of China under Grant No.3122016L010the National Natural Science Foundation of China under Grant No.11705279+1 种基金supported by the Zhejiang Provincial Natural Science Foundation of China under Grant No.LR16A050001the National Natural Science Foundation of China under Grant Nos.11622538 and 61673150
文摘The network dismantling problem asks the minimum separate node set of a graph whose removal will break the graph into connected components with the size not larger than the one percentage of the original graph.This problem has attracted much attention recently and a lot of algorithms have been proposed. However, most of the network dismantling algorithms mainly focus on which nodes are included in the minimum separate set but overlook how to order them for removal, which will lead to low general efficiency during the dismantling process. In this paper,we reformulate the network dismantling problem by taking the order of nodes’ removal into consideration. An efficient dismantling sequence will break the network quickly during the dismantling processes. We take the belief-propagation guided decimation(BPD) dismantling algorithm, a state-of-the-art algorithm, as an example, and employ the node explosive percolation(NEP) algorithm to reorder the early part of the dismantling sequence given by the BPD. The proposed method is denoted as the NEP-BPD algorithm(NBA) here. The numerical results on Erd¨os-R′enyi graphs,random-regular graphs, scale-free graphs, and some real networks show the high general efficiency of NBA during the entire dismantling process. In addition, numerical computations on random graph ensembles with the size from 210 to219 exhibit that the NBA is in the same complexity class with the BPD algorithm. It is clear that the NEP method we used to improve the general efficiency could also be applied to other dismantling algorithms, such as Min-Sum algorithm,equal graph partitioning algorithm and so on.
基金supported by the National Natural Science Foundation of China(21477156,21277165)the National Basic Research Program of China(2015CB453101)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB14010100)
文摘Atmospheric concentrations of Dechlorane Plus(DP)were investigated in Taizhou,an electronic-waste(E-waste)dismantling region in East China.Passive air samplers with polyurethane foam(PUF)disks were deployed every three months during the sampling period of September 2009-August 2010.The total DP(syn-and anti-DP)concentrations in air ranged from not detected to 277 pg/m^3,with a mean concentration of 53.9 pg/m^3.A generally declining trend of DP levels was found from the E-waste dismantling region to the peripheral areas.The median values of total DP concentrations in autumn,winter,spring and summer were 52.2,28.8,39.7 and 30.1 pg/m^3,respectively.The seasonal variations of DP concentrations were mainly associated with the intensity of E-waste dismantling activities and meteorological conditions.The mean value of anti-DP fractional abundance(f_(anti))was 0.74±0.08,which was consistent with those in the commercial DP products.This study confirmed a significant emission source related to the distribution of atmospheric DP in the E-waste dismantling area and supplied information for the seasonal variation of DP in the atmosphere.
文摘The 34th meeting of the 18th Central Leading Group on Deepening Reform adopted the Implementation Plan on Banning the Entry of Foreign Waste and Promoting the Reform of Solid Waste Import Management System in April 2017,and decided to phase out the import of solid waste by 2019.In April 2018,the Ministry of Ecological Environment.