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Development of a high-repetition-rate lumped-inductance kicker magnet prototype for the beam switchyard of SHINE
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作者 Yong-Fang Liu Rui-Ping Wang +6 位作者 Jin Tong Bo Zhang Si Chen Qi-Bing Yuan Hai-Xiao Deng Ming Gu Bo Liu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期20-31,共12页
The Shanghai high-repetition-rate X-ray free-electron laser and extreme light facility(SHINE)operates at a maximum repetition rate of 1 MHz.Kicker magnets are key components that distribute electron bunches into three... The Shanghai high-repetition-rate X-ray free-electron laser and extreme light facility(SHINE)operates at a maximum repetition rate of 1 MHz.Kicker magnets are key components that distribute electron bunches into three different undulator lines in a bunch-by-bunch mode.The kicker field width must be less than the time interval between bunches.A lumpedinductance kicker prototype was developed using a vacuum chamber with a single-turn coil.The full magnetic field strength was 0.005 T.This paper presents the requirements,design considerations,design parameters,magnetic field calculations,and measurements of the kicker magnets.The relevant experimental results are also presented.The pulse width of the magnetic field was approximately 600 ns,and the maximum operation repetition rate was 1 MHz.The developed kicker satisfies the requirements for the SHINE project.Finally,numerous recommendations for the future optimization of kicker magnets are provided. 展开更多
关键词 X-ray free-electron laser Kicker magnet Beam switchyard High repetition rate Ni-Zn ferrites
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Food Security Problems and Solutions in China Based on the Strategy of Sustainable Agricultural Development
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作者 Chongzhe JIAO 《Asian Agricultural Research》 2024年第2期16-17,30,共3页
China attaches great importance to food security.With the strong promotion of the government,Chinas grain output has achieved a great feat from"shortage"to"surplus in bumper years"and then to"... China attaches great importance to food security.With the strong promotion of the government,Chinas grain output has achieved a great feat from"shortage"to"surplus in bumper years"and then to"rising steadily",achieving a record"increase for the tenth consecutive year".From the current balance of food supply and demand in China,the food security situation can be guaranteed on the whole.However,if we analyze the food security in China from the perspective of agricultural sustainable development strategy,there are some difficulties,such as the reduction of cultivated land area,the decline of cultivated land quality,the fragility of agricultural ecological environment,and the transformation of residentsconsumption structure.This paper analyzes the difficulties faced by the development of food security in China under the strategy of sustainable agricultural development,and puts forward that to implement the strategy of sustainable agricultural development,it is necessary to realize the coordinated development of food security,science and technology,ecological environment,resources and society. 展开更多
关键词 Sustainable development Food security Ecological environment
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Development and Application of Integrated Indicators for Assessing Healthcare Waste Management Systems in Kenyan Hospitals
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作者 Muriithi Jackson Githinji Paul Mwangi Njogu +1 位作者 Zipporah Nganga Mohamed Karama 《Open Journal of Applied Sciences》 2024年第4期1080-1120,共41页
Healthcare waste management (HCWM) is an important aspect of healthcare delivery globally because of its hazardous and infectious components that have potential for adverse health and environmental impacts. The paper ... Healthcare waste management (HCWM) is an important aspect of healthcare delivery globally because of its hazardous and infectious components that have potential for adverse health and environmental impacts. The paper introduces a set of indicators for assessing HCWM systems in hospitals. These indicators are: HCWM policies and standard operating procedures, management and oversight, logistics and budget support, training and occupational health and safety, and treatment, disposal and waste treatment equipment housing. By plotting a mark on a continuum which is defined as good and poor on the extremes and is connected with all other marks in a spoke arrangement, it’s possible to describe a baseline for HCWM in any specific hospital. This baseline can be used to improve awareness of the actors and policy-makers, compare the same hospital at a different point in time, to compare observations by different evaluators and to track improvements. Results suggest that in Kenya, the application of such indicators is useful for evaluating which priorities should be addressed to improve outcomes in HCWM systems. Systematic sampling technique was used to identify and collect data by use of observational checklist, interviews, visual verification and review of documents and a HCWM assessment tool. The objective is to suggest an integrated management tool as a method to identify prevailing problems with a HCWM system. The method can be replicated in other contexts worldwide, with a focus on the developing world. The integrated indicators focus on management of HCW and not its potential impact on human health and environment, an area recognized to be critical for future research. 展开更多
关键词 Developing Countries HCW Management Indicators Management Tools
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Integrated Development of Tea and Tourism in Taishan Mountain Tea Valley in the Context of Rural Revitalization
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作者 Dongmei ZHANG Mengzhen SONG 《Asian Agricultural Research》 2024年第1期1-9,共9页
In recent years,the integrated development of the tea and tourism has become an important way to promote the rural revitalization of Tai'an tea-producing areas,but the state of industrial upgrading still needs to ... In recent years,the integrated development of the tea and tourism has become an important way to promote the rural revitalization of Tai'an tea-producing areas,but the state of industrial upgrading still needs to be improved.In order to better integrate tea and tourism in Tea Valley,this paper uses questionnaire and SWOT analysis to study.It found the following problems:(i)45.7%of tourists were interested in tea culture,but they know litle about it,and the integration of tea culture and tea tourism products is low.(i)50.54%of the tourists were interested in the tea picking experience project and wanted to add the tea food experience item.(ii)The acceptance of 45.7%of tourists to scenic spots was 1-2 h,which shows that the quality of transportation service facilities and personnel needs to be improved.Combined with the SWOT analysis,it is found that the scenic spot is rich in resources,convenient transportation,profound cultural heritage,and good govern-ment policy support conditions,which is suitable for the SO strategy(growth development strategy),so the scenic spot relies on internal ad-vantages and seizes external opportunities to develop the integration of tea and tourism.Based on the analysis results,it came up with the perti-nent recommendations for the key problems:(i)The infrastructure service is not well established.It is suggested that scenic spots should in-crease investment,regularly train service personnel to improve their quality,and improve transportation services,accommodation,catering and public service hardware facilities.(i)Tea tourism products are insufficient.It is suggested that tea tourism products should be innovatively designed and tea tourism experiential products and tourism commodities should be planned.(i)Tea culture and tourism lack organic combi-nation.It is recommended to deeply excavate tea culture,and take consideration of both spiritual and material aspects.The specific methods include building teahouses,Taishan Mountain(Mount Tai)tea culture throughout the whole process of tea production,development and pro-cessing,and AR tea culture experience hall can be built to make tourists feel tea culture from dfferent perspectives.(iv)The publicity is in-sufficient.Strategies should be made in three aspects:improving the Internet media,taking into account the traditional media,and expanding the market based on the surrounding areas.(v)The tea industry chain is short.It is recommended to add four new industrial chain designs of"tea+accommodation,tea+catering,tea+Intemet,tea+training",hoping to bring some inspiration and ideas to the managers of scenic spots. 展开更多
关键词 Integrated development of tea and tourism Tai'an Tea Valley Problems Countermeasures and recommendations
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The Impact of Sustainable Development Strategies on Corporate Performance
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作者 Lingli Li 《Proceedings of Business and Economic Studies》 2024年第1期1-7,共7页
Enterprises must develop and implement effective strategic measures to achieve sustainable development.This entails evaluating corporate performance,understanding the impact of sustainable development strategies on co... Enterprises must develop and implement effective strategic measures to achieve sustainable development.This entails evaluating corporate performance,understanding the impact of sustainable development strategies on corporate performance,and implementing such strategies.The article proposes eight critical countermeasures to foster harmony and sustainable development among humanity,nature,the economy,and society:innovation-driven initiatives,green development practices,social responsibility initiatives,talent cultivation programs,collaborative cooperation efforts,sound financial management,brand-building endeavors,and effective information management. 展开更多
关键词 Sustainable development Corporate performance Innovative development
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Measurement and Strategy Research on the Green Development Level for the New Energy Vehicle Industry in Chongqing City
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作者 HE Qian 《Journal of Literature and Art Studies》 2024年第3期247-264,共18页
This article takes 2016-2022 as the inspection period to construct an evaluation index system for the green development level of the new energy vehicle industry.The entropy method and comprehensive index are used to m... This article takes 2016-2022 as the inspection period to construct an evaluation index system for the green development level of the new energy vehicle industry.The entropy method and comprehensive index are used to measure the green development level of the new energy vehicle industry in Chongqing,and compared with neighboring provinces such as Yunnan,Guizhou,and Sichuan.Policy recommendations are proposed to promote the development of the new energy vehicle industry in Chongqing City. 展开更多
关键词 Chongqing City new energy vehicle industry green development level
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Innovative Technologies for Large-Scale Water Production in Arid Regions: Strategies for Sustainable Development
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作者 Boris Menin 《Journal of Applied Mathematics and Physics》 2024年第7期2506-2558,共53页
Water scarcity in arid regions poses significant challenges to sustainable development and human well-being. This article explores both existing and innovative technologies and methods to produce large amounts of wate... Water scarcity in arid regions poses significant challenges to sustainable development and human well-being. This article explores both existing and innovative technologies and methods to produce large amounts of water to address these challenges effectively. Key approaches include atmospheric water generation, advanced desalination techniques, innovative water collection methods such as fog nets and dew harvesting, geothermal water extraction, and water recycling and reuse. Each method is evaluated for its feasibility with existing technology, potential time of implementation, required investments, and specific challenges. By leveraging these technologies and combining them into a multifaceted water management strategy, it is possible to enhance water security, support agricultural and industrial activities, and improve living conditions in arid regions. Collaborative efforts between governments, private sector entities, and research institutions are crucial to advancing these technologies and ensuring their sustainable implementation. The article provides a comprehensive overview of the current state of these technologies, their potential for large-scale application, and recommendations for future research and development. 展开更多
关键词 Atmospheric Water Generation Advanced Desalination Sustainable development Geothermal Water Extraction Water Recycling Arid Regions Water Security
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Building a Business and Strategic Intelligence Policy as a Strategy for Promoting Congolese Business Progress and Healthy Economic Development in Eastern DRC
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作者 Innocent Bora Uzima 《Intelligent Information Management》 2024年第2期77-103,共27页
The aim of this study was to verify the existence of business and strategic intelligence policies at the level of Congolese companies and at the state level, likely to foster progress and healthy development in the ea... The aim of this study was to verify the existence of business and strategic intelligence policies at the level of Congolese companies and at the state level, likely to foster progress and healthy development in the east of the DRC. The study was based on a mixed perspective consisting of objective analysis of quantitative data and interpretative analysis of qualitative data. The results showed that business and strategic intelligence policies have not been established at either company or state level, as this is an area of activity that is not known to the players in companies and public departments, and there are no units or offices in their organizational structures responsible for managing strategic information for competitiveness on the international market. In addition, there is a real need to establish strategic information management units within companies, upstream, and to set up a national strategic information management department or agency to help local companies compete in the marketplace, downstream. This reflects the importance and timeliness of building business and strategic intelligence policies to ensure economic progress and development in the eastern DRC. Business and strategic intelligence provides companies with an appropriate tool for researching, collecting, processing and disseminating information useful for decision-making among stakeholders, in order to cope with a crisis or competitive situation. The study suggests a number of key recommendations based on its findings. To the government, it is recommended to establish the national policy of business and strategic intelligence by setting up a national agency of strategic intelligence in favor of local companies;and to companies to establish business intelligence units in their organizational structures in favor of stakeholders to foster advantageous decision-making in the competitive market and achieve progress. Finally, the study suggests that studies be carried out to fully understand the opportunities and impact of business and strategic intelligence in African countries, particularly in the DRC. 展开更多
关键词 Business and Strategic Intelligence Strategic Information Congolese Companies Public Departments Decision-Making Information Management Business and Strategic Intelligence Policies PROGRESS Healthy development Mining and Agriculture Sectors International Market Eastern DRC
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Research on the Development Strategy of Smart Tourism in Hainan Under the Background of Big Data
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作者 Limei Fu 《Journal of Contemporary Educational Research》 2024年第4期108-113,共6页
Hainan is a major tourist province.It is urgent to promote the transformation and upgrading of Hainan’s tourism industry from a traditional service industry to a modern service industry by means of informatization.Sm... Hainan is a major tourist province.It is urgent to promote the transformation and upgrading of Hainan’s tourism industry from a traditional service industry to a modern service industry by means of informatization.Smart tourism is a brand-new tourism form and operation mode of tourism transformation and upgrading.Integrating big data technology will make smart tourism more accurate in three aspects:tourism management,tourism service,and tourism marketing,and further enhance the satisfaction of the tourism experience.This paper studies the development status of smart tourism in Hainan,deeply summarizes its existing problems and causes,and puts forward the development strategy of smart tourism in Hainan to promote the healthy development of the tourism industry in Hainan. 展开更多
关键词 Big data Smart tourism development strategy
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Analysis of Innovative Paths for Enterprise Marketing Management Development Strategy under the Background of New Media
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作者 Tao Chi 《Proceedings of Business and Economic Studies》 2024年第3期28-34,共7页
From the perspective of enterprise marketing strategy planning,innovative research should be conducted based on the current trends in new media.The findings should be applied to practical activities within enterprises... From the perspective of enterprise marketing strategy planning,innovative research should be conducted based on the current trends in new media.The findings should be applied to practical activities within enterprises to achieve innovation in marketing strategy decision-making in the new media environment.Enterprises should adopt advanced communication transmission technologies and big data processing capabilities to effectively leverage the hidden value and promotional planning advantages of network media platforms.This approach can enhance customer loyalty and increase demand for new products.Enterprises should integrate into the continuously evolving new media landscape,explore their potential business characteristics,and innovate promotional methods.By effectively combining product information with digital media content,companies can ultimately achieve significant increases in corporate interests. 展开更多
关键词 New media Enterprise marketing management development strategy INNOVATION
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Exploration of Teaching Development Strategies for Double-Qualified Teachers in University- Affiliated Hospitals Based on Role Conflict Theory
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作者 Yuanyuan Jia Yu Cai +2 位作者 Siqi Wang Ying Yang Ge Wu 《Journal of Contemporary Educational Research》 2024年第6期121-127,共7页
This study draws on the classic theories and research achievements of university teacher development,and from the perspective of role conflict in social psychology,proposes policy recommendations for the development o... This study draws on the classic theories and research achievements of university teacher development,and from the perspective of role conflict in social psychology,proposes policy recommendations for the development of clinical teachers in medical colleges,including following different stages of teacher development and designing teaching development strategies at different levels;designing the content and form of teaching development activities to meet the temporal and spatial needs of clinical teachers;and building an academic community for clinical teachers to promote the creation of teaching development behaviors. 展开更多
关键词 University-affiliated hospitals Double-qualified teachers Role conflict theory Teaching development strategies
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Development Strategy of Sichuan Sports Museum under the Background of Cultural and Tourism Integration
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作者 Junxian Feng 《Proceedings of Business and Economic Studies》 2024年第3期173-178,共6页
Through conducting a SWOT analysis of the Chengdu Sports Institute Museum,and utilizing the 4M management,5W display,and 4P marketing theoretical models,this study explores effective strategies suitable for Sichuan sp... Through conducting a SWOT analysis of the Chengdu Sports Institute Museum,and utilizing the 4M management,5W display,and 4P marketing theoretical models,this study explores effective strategies suitable for Sichuan sports museums in terms of functionality,display,and marketing. 展开更多
关键词 Integration of culture and tourism Sports museum development strategy
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Computational Strategy Research on the Development of Kiruna,in Sweden
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作者 Ruocheng Sun 《建筑工程(中英文版)》 2024年第1期9-19,共11页
In Kiruna,nearly all the residents support the migration plan in order to make LKAB able to continue the mining process.Based on current condition,a larger part of this town will be demolished by the sinking land caus... In Kiruna,nearly all the residents support the migration plan in order to make LKAB able to continue the mining process.Based on current condition,a larger part of this town will be demolished by the sinking land caused by iron ore mining processing operated by LKAB.Since then,most of the buildings in the sinking district will be relocated in another district.However,the situation in Kiruna is not quite the same as when this kind of migration happens in another place.In other place,while migration happens,even if not most,a large part of the local residents will resist and fight for their house and properties.Concentrated on the ownership of different buildings and tried find the relationship between the public and private buildings to discover some issue that will help to work on the computational urban design. 展开更多
关键词 Iron Mine Economic PUBLIC PRIVATE Property OWNERSHIP TRANSPORTATION EMPLOYMENT Economical System development History Swarm Intelligence Logic Processing
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Socio-economic and energy-environmental impacts of technological change on China's agricultural development under the carbon neutrality strategy 被引量:1
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作者 Hong-Dian Jiang Rui Yu Xiang-Yan Qian 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期1289-1299,共11页
Promoting agricultural modernisation through technological change is an important strategy for China.China's carbon neutrality strategy is leading to systemic socio-economic changes that could exacerbate the uncer... Promoting agricultural modernisation through technological change is an important strategy for China.China's carbon neutrality strategy is leading to systemic socio-economic changes that could exacerbate the uncertainty of agricultural development.Therefore,applying a computable general equilibrium(CGE)model,this study characterises the agricultural sector in detail,introducing endogenous technological change proxied by research and development(R&D)to assess the impact of different technological change scenarios on agricultural development under the carbon neutrality target.The results show that allocating carbon revenue for R&D inputs can mitigate the significant negative impact of achieving carbon neutrality on knowledge capital and production in agricultural sectors.Overall,using carbon revenue only for R&D input in crop sectors has the optimal effect on increasing the agricultural sectors'knowledge capital,improving crop production and profit,reducing crop external dependence and promoting the synergistic reduction of carbon and pollutant emissions.However,this scenario has the largest negative impact on macro-economics and household welfare.In contrast,allocating carbon revenue to promote technological change in broader non-energy sectors or both crops and non-energy sectors can effectively mitigate negative socio-economic impacts,but the positive impact on agricultural development is minimal.These findings provide practical insights for the rational use of carbon revenue to expand agricultural R&D investment and ensure balanced agricultural and economic development under the carbon neutrality target. 展开更多
关键词 Endogenous technological change R&D investment Agriculture development Computable general equilibrium
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Supplementing the early diet of broilers with soy protein concentrate can improve intestinal development and enhance short-chain fatty acid-producing microbes and short-chain fatty acids,especially butyric acid 被引量:1
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作者 Qianyun Zhang Shan Zhang +2 位作者 Shu Wu Marianne Hjollund Madsen Shourong Shi 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第1期278-294,共17页
Background:Research on nutrition in early-life commonly focuses on the maturation of the intestine because the intestinal system is crucial for ensuring continued growth.To explore the importance of early nutrition re... Background:Research on nutrition in early-life commonly focuses on the maturation of the intestine because the intestinal system is crucial for ensuring continued growth.To explore the importance of early nutrition regulation in animals,soy protein concentrate(SPC)was added to the early diet of broilers to investigate its effects on amino acid digestibility,intestinal development,especially intestinal microorganisms,and broiler metabolites.A total of 192 oneday-old Arbor Acres(AA)male broilers were randomly assigned to two experimental treatments with 8 replicates of 12 birds.The control group was fed a basal diet(control),and the treatment group was fed a basal diet supplemented with 12%SPC(SPC12)during the first 10 d(starter phase).From d 11 to 21(grower phase)and d 22 to 42(finisher phase),a basal diet was fed to both treatment groups.Results:SPC reduced the pH value and acid-binding capacity of the starter diet(P<0.05,d 10);SPC in the early diet enhanced the gizzard weight(P<0.05,d 10 and d 42)and the ileum weight(P<0.05,d 10)and decreased the weight and length of the jejunum(P<0.05,d 10)and the relative length of the duodenum and jejunum(P<0.05,d 10).At the same time,SPC enhanced villus height(P<0.05,d 10)and muscle thickness in the jejunum and ileum(P<0.05,d 10)and increased the number of goblet cells in the duodenum(P<0.05,d 10).Meanwhile,SPC increased the Chao1 index and the ACE index(P<0.05,d 10)and altered the composition of caecal microflora at d 10.SPC also increased the relative abundance of Alistipes,Anaerotruncus,Erysipelatoclostridium,Intestinimonas and Flavonifractor bacteria(P<0.05,d 10).At the same time,the concentrations of caecal butyric acid and total short-chain fatty acids(SCFAs)were also increased in the SPC12 group(P<0.05,d 10).Conclusions:In summary,the results showed that supplementing the starter diet of broilers with SPC has a significant effect on the early development of the intestine and the microflora. 展开更多
关键词 BROILER Caecal microbiota Intestinal development Short-chain fatty acids Soy protein concentrate
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The status and development strategy of coalbed methane industry in China 被引量:1
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作者 XU Fengyin HOU Wei +11 位作者 XIONG Xianyue XU Borui WU Peng WANG Hongya FENG Kun YUN Jian LI Shuguang ZHANG Lei YAN Xia FANG Huijun LU Qian MAO Delei 《Petroleum Exploration and Development》 SCIE 2023年第4期765-783,共19页
To achieve the goals of carbon peaking and carbon neutrality under the backgrounds of poor resource endowments, weak theoretical basis and other factors, the development of the coalbed methane industry of China faces ... To achieve the goals of carbon peaking and carbon neutrality under the backgrounds of poor resource endowments, weak theoretical basis and other factors, the development of the coalbed methane industry of China faces many bottlenecks and challenges. This paper systematically analyzes the coalbed methane resources, key technologies and progress, exploration effect and production performance in China and abroad. The main problems are summarized as low exploration degree, low technical adaptability, low return on investment and small development scale. This study suggests that the coalbed methane industry in China should follow the “two-step”(short-term and long-term) development strategy. The short-term action before 2030, can be divided into two stages:(1) From the present to 2025, to achieve new breakthroughs in theory and technology, and accomplish the target of annual production of 10 billion cubic meters;(2) From 2025 to 2030, to form the technologies suitable for most geological conditions, further expand the industry scale, and achieve an annual output of 30 billion cubic meters, improving the proportion of coalbed methane in the total natural gas production. The long-term action after 2030 is to gradually realize an annual production of 100 billion cubic meters. The strategic countermeasure to achieve the above goals is to adhere to “technology+management dual wheel drive”, realize the synchronous progress of technology and management, and promote the high-quality development of the coalbed methane industry. Technically, the efforts will focus on fine and effective development of coalbed methane in the medium to shallow layers of mature fields, effective development of coalbed methane in new fields, extensive and beneficial development of deep coalbed methane, three-dimensional comingled development of coalbed methane, applying new technologies such as coalbed methane displacement by carbon dioxide, microwave heating and stimulation technology, ultrasonic stimulation, high-temperature heat injection stimulation, rock breaking by high-energy laser. In terms of management, the efforts will focus on coordinative innovation of resource, technology, talent, policy and investment, with technological innovation as the core, to realize an all-round and integrated management and promote the development of coalbed methane industry at a high level. 展开更多
关键词 coalbed methane industry status strategic goal development countermeasures combined gas mining enhanced recovery in-situ conversion
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Research on strategic risk identification method of equipment system development based on system dynamics 被引量:1
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作者 WANG Xinfeng WANG Tao +1 位作者 ZHOU Xin WANG Yanfeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第5期1225-1234,共10页
Strategic management of equipment system develop-ment must attach importance to effective strategic risk manage-ment.Aiming at the identification of strategic risk of equipment system development,firstly,the source of... Strategic management of equipment system develop-ment must attach importance to effective strategic risk manage-ment.Aiming at the identification of strategic risk of equipment system development,firstly,the source of strategic risk of equip-ment system development is analyzed and classified.Based on this,a causal loop diagram of strategic risk of equipment sys-tem development based on system dynamics is established.The system dynamics analysis software Vensim PLE is used to carry out the risk influencing factors analysis,risk consequences ana-lysis,risk feedback loop identification and corresponding pre-control measures,and achieves a good risk identification effect. 展开更多
关键词 equipment system development strategy manage-ment strategic risk management risk identification system dynamics loop diagram of causality
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Effects of polyamines on the early development of cystocarps,spore release,survival,and germination rate of Gracilariopsis lemaneiformis
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作者 Deguang SUN Emon RAHMAN +2 位作者 Siqi SUN Xue SUN Nianjun XU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第3期1133-1144,共12页
Three polyamines(PAs)(spermidine(Spd),spermine(Spm),and putrescine(Put))were used as growth regulators to the marine macroalgae Gracilariopsis lemaneiformis and to female gametophyte and reproductive tissues(cystocarp... Three polyamines(PAs)(spermidine(Spd),spermine(Spm),and putrescine(Put))were used as growth regulators to the marine macroalgae Gracilariopsis lemaneiformis and to female gametophyte and reproductive tissues(cystocarps were constructed),which led to early maturation of cystocarps and spore release.Laboratory cultivation revealed that exogenous PA application accelerated the development of cystocarps,and the mean sporeling growth rate was 20%–50%/d during the initial week of cultivation.The spore count(SC),survival rate(SR),and germination rate(GR)of G.lemaneiformis showed different responses to PA(10-6 mol/L and 10-3 mol/L)treatments under different temperatures(18,26,and 34℃),light intensities(30,60,and 90μmol photons/(m^(2)·s)),salinities(25,30,and 35),and nutrient levels(25꞉2.5,50꞉5.0,and 75꞉7.5μmol/L NH4Cl꞉K2HPO4),and the optimal conditions were 26℃,light intensity of 60μmol/(m^(2)·s),salinity of 35,and nutrient level of 50꞉5.0μmol/L NH4Cl꞉K2HPO4.Under the optimum conditions,the SC per cystocarp increased by 82.38%,and the spore SR and GR increased by 33.07%and 46.44%,respectively.Each experiment lasted for 7 days,with the highest SC on Day 4 and plateauing on Day 7.The results indicate that PAs could promote the early maturation,spore release,survival,and germination of G.lemaneiformis under laboratory conditions. 展开更多
关键词 Gracilariopsis lemaneiformis polyamines carpospores spore release survival rate germination rate
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Experimental study on the effect of unloading rate on gneiss rockburst 被引量:1
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作者 Dongqiao Liu Jie Sun +4 位作者 Ran Li Manchao He Binghao Cao Chongyuan Zhang Wen Meng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2064-2076,共13页
Rockburst are often encountered in tunnel construction due to the complex geological conditions.To study the influence of unloading rate on rockburst,gneiss rockburst experiments were conducted under three groups of u... Rockburst are often encountered in tunnel construction due to the complex geological conditions.To study the influence of unloading rate on rockburst,gneiss rockburst experiments were conducted under three groups of unloading rates.A high-speed photography system and acoustic emission(AE)system were used to monitor the entire process of rockburst process in real-time.The results show that the intensity of gneiss rockburst decreases with decrease of unloading rate,which is manifested as the reduction of AE energy and fragments ejection velocity.The mechanisms are proposed to explain this effect:(i)The reduction of unloading rate changes the crack propagation mechanism in the process of rockburst.This makes the rockbursts change from the tensile failure mechanism at high unloading rate to the tension-shear mixed failure mechanism at low unloading rate,and more energy released in the form of shear crack propagation.Then,less strain energy is converted into kinetic energy of fragments ejection.(ii)Less plate cracking degree of gneiss has taken shape due to decrease of unloading rate,resulting in the destruction of rockburst incubation process.The enlightenments of reducing the unloading rate for the project are also described quantitatively.The rockburst magnitude is reduced from the medium magnitude at the unloading rate of 0.1 MPa/s to the slight magnitude at the unloading rate of 0.025 MPa/s,which was judged by the ejection velocity. 展开更多
关键词 ROCKBURST Unloading rate Crack propagation Influence mechanisms
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GAMYB transcription factor LoMYB65 from lily plays a vital role in pollen development 被引量:1
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作者 Xinyue Liu Ling He +1 位作者 Ze Wu Nianjun Teng 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第1期223-238,共16页
Lily(Lilium spp.)is an important horticultural crop,but its use is limited due to serious pollen contamination problems.There are many studies on pollen development in model plants,but few on flower crops such as lili... Lily(Lilium spp.)is an important horticultural crop,but its use is limited due to serious pollen contamination problems.There are many studies on pollen development in model plants,but few on flower crops such as lilies.Gibberellin(GA)is a large class of hormones and plays an important role in plant vegetative growth and reproductive development.GAMYB is a group of the R2R3-MYB family upregulated by gibberellin,and plays an important role in anther development.Here,we isolated a novel GAMYB,named LoMYB65,from lily,which was closely related to the AtMYB65 and AtMYB33 in Arabidopsis.Fluorescence quantitative PCR results showed that LoMYB65 was mainly expressed in lily anthers.LoMYB65 could be activated by 288μmol·L^(-1)GA3treatment and the LoMYB65 protein was located in the nucleus and cytoplasm,and had transactivation in yeast and tobacco leaf cells.The conserved motif within 226 amino acids of the C-terminal of LoMYB65 contributed to its transactivation.Overexpression of LoMYB65 caused dwarf phenotype,unnormal tapetum development,less seeds of siliques in transgenic Arabidopsis plants,the transgenic plants showed partly male sterile.Simultaneously,silencing of LoMYB65 with VIGS(Virus Induced Gene Silencing)in lily anthers caused unnormal pollen development and reduced the pollen amount.Overexpression of LoMYB65 in Arabidopsis and silencing of LoMYB65 in lily resulted in decreased pollen counts,so we speculate that LoMYB65 may be dose-dependent.Overall,these findings suggest that LoMYB65 may play an important role in anther development and pollen formation in lily.LoMYB65 may provide a useful candidate gene for pollenless breeding of lily. 展开更多
关键词 LILY Anther development Pollen pollution GAMYB VIGS
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