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New food sources and production systems:a comparison of international regulations and China’s advancements in novel foods with synthetic biology
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作者 Xin Liu Di Wu +1 位作者 Yi Shao Yongning Wu 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2519-2542,共24页
The global shift towards sustainable food systems has sparked innovations in food sources and production systems,including cell-based meat,plant-based food products,precision fermentation,and 3D food printing.These ad... The global shift towards sustainable food systems has sparked innovations in food sources and production systems,including cell-based meat,plant-based food products,precision fermentation,and 3D food printing.These advancements pose regulatory challenges and opportunities,with China emerging as a critical player in adopting and regulating new food technologies.This review explores the international landscape of new food sources and production systems(NFPS),focusing on China’s role and regulatory approaches compared to global practices.Through this comparative analysis,we aim to contribute to the ongoing dialogue on food safety regulation,offering insights and recommendations for policymakers,industry stakeholders,and researchers engaged in the global food system’s evolution.This comprehensive overview underscores the dynamic nature of regulatory frameworks governing NFPS,highlighting the international efforts to ensure food safety,consumer protection,and the sustainable evolution of the food industry. 展开更多
关键词 New food sources Food production system Food safety International regulation Synthetic biology China
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Combinatorial reasoning-based abnormal sensor recognition method for subsea production control system
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作者 Rui Zhang Bao-Ping Cai +3 位作者 Chao Yang Yu-Ming Zhou Yong-Hong Liu Xin-Yang Qi 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2758-2768,共11页
The subsea production system is a vital equipment for offshore oil and gas production.The control system is one of the most important parts of it.Collecting and processing the signals of subsea sensors is the only way... The subsea production system is a vital equipment for offshore oil and gas production.The control system is one of the most important parts of it.Collecting and processing the signals of subsea sensors is the only way to judge whether the subsea production control system is normal.However,subsea sensors degrade rapidly due to harsh working environments and long service time.This leads to frequent false alarm incidents.A combinatorial reasoning-based abnormal sensor recognition method for subsea production control system is proposed.A combinatorial algorithm is proposed to group sensors.The long short-term memory network(LSTM)is used to establish a single inference model.A counting-based judging method is proposed to identify abnormal sensors.Field data from an offshore platform in the South China Sea is used to demonstrate the effect of the proposed method.The results show that the proposed method can identify the abnormal sensors effectively. 展开更多
关键词 Abnormal sensor Combinatorial algorithm Fault identification Subsea production control system
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Rural labor migration and farmers’arrangements of rice production systems in Central China:Insight from the intergenerational division of labor
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作者 Xue Shen Quanyu Yang +1 位作者 Rongjun Ao Shengsheng Gong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第9期3200-3214,共15页
Rice production is crucial for food security in China,and its relationship with rural labor migration has been studied extensively.Labor migration in rural China has taken new forms in recent years.There has been a di... Rice production is crucial for food security in China,and its relationship with rural labor migration has been studied extensively.Labor migration in rural China has taken new forms in recent years.There has been a discernible trend wherein adult children have started migrating to cities while their elderly parents return to villages to re-engage in on-farm work.The phenomenon has notably shaped the intergenerational division of labor(IDL)within households.However,it remains to be seen how farmers adjust their rice production systems in response to the IDL.The age of 60 years for employment injury insurance is the eligibility threshold for off-farm employment and is used to obtain a source of exogenous variation in the IDL.Based on a representative household survey of 1,752 rice farmers in the Hubei Province of Central China,our fuzzy regression discontinuity analysis reveals that farmers in IDL households are more likely to adopt ratoon rice(RR)than single cropping rice(SR)or double cropping rice(DR).The effect of the IDL varies under different levels of operational scales and specialized agricultural service availability.Further analysis suggests that farmers’arrangements are associated with two potential mechanisms of downward intergenerational transfer.Monetary transfer for urban housing purchases increases RR in IDL households,and time transfer for intergenerational childcare significantly promotes SR in IDL households.This study enhances the understanding of the relationship between rural labor migration and rice production in China,providing a reference for adjusting rice production systems to ensure food security. 展开更多
关键词 labor migration intergenerational division of labor rice production systems fuzzy regression discontinuity Central China
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Research on typical operating conditions of hydrogen production system with off-grid wind power considering the characteristics of proton exchange membrane electrolysis cell
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作者 Weiming Peng Yanhui Xu +4 位作者 Gendi Li Jie Song Guizhi Xu Xiaona Xu Yan Pan 《Global Energy Interconnection》 EI CSCD 2024年第5期642-652,共11页
Hydrogen energy,with its abundant reserves,green and low-carbon characteristic,high energy density,diverse sources,and wide applications,is gradually becoming an important carrier in the global energy transformation a... Hydrogen energy,with its abundant reserves,green and low-carbon characteristic,high energy density,diverse sources,and wide applications,is gradually becoming an important carrier in the global energy transformation and development.In this paper,the off-grid wind power hydrogen production system is considered as the research object,and the operating characteristics of a proton exchange membrane(PEM)electrolysis cell,including underload,overload,variable load,and start-stop are analyzed.On this basis,the characteristic extraction of wind power output data after noise reduction is carried out,and then the self-organizing mapping neural network algorithm is used for clustering to extract typical wind power output scenarios and perform weight distribution based on the statistical probability.The trend and fluctuation components are superimposed to generate the typical operating conditions of an off-grid PEM electrolytic hydrogen production system.The historical output data of an actual wind farm are used for the case study,and the results confirm the feasibility of the method proposed in this study for obtaining the typical conditions of off-grid wind power hydrogen production.The results provide a basis for studying the dynamic operation characteristics of PEM electrolytic hydrogen production systems,and the performance degradation mechanism of PEM electrolysis cells under fluctuating inputs. 展开更多
关键词 Wind power fluctuation Off-grid operation Hydrogen production by PEM electrolysis Neural network clustering Typical working conditions
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Exploration of Earth-Abundant Transition Metals(Fe,Co,Ni)Doped on W_(18)O_(49)System as Electrocatalysts for Urea Productiont
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作者 Kaile Li Changyan Zhu +6 位作者 Xiaohui Yao Ao Yang Yunjie Chu Mengxue Wang Yun Geng Zhongmin Su Min Zhang 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第5期605-613,I0041-I0050,I0099,共20页
The conversion of inert N_(2)and CO_(2)into urea by electrocatalytic technology not only reduces the cost of urea synthesis in future,but also alleviatesthe environmental pollution problem caused by carbon emission in... The conversion of inert N_(2)and CO_(2)into urea by electrocatalytic technology not only reduces the cost of urea synthesis in future,but also alleviatesthe environmental pollution problem caused by carbon emission in traditional industrial production.However,facing downside factors such as strong competitive reactions and unclear reaction mechanism,the design of high-performance urea catalysts is imminent.This study demonstrates that W_(18)O_(49)system doped heteronuclear metals(TM=Fe,Co,Ni)can effectively solve the problem of competitive adsorption between N_(2)and CO_(2)and realize the co-adsorption of N_(2)and CO_(2)at diverse sites.Their theoretical limiting voltages for urea production on TM-W_(18)O_(49)(TM=Fe,Co,Ni)systems are-0.46 V,-0.42 V and-0.52 V,respectively.The results are all lower than that of the contrastive voltage in pristine W_(18)O_(49)system(-0.91 V),further indicating the rationality and necessity of single-atom doped strategy for the co-reduction of two molecules.Specially,Co-W_(18)O_(49)can theoretically inhibit the side reactions of NRR,CO_(2)RR,and HER,which deserve future experimental exploration in future.The study suggests that doping heteronuclear metal into transition metal oxides is a feasible scheme to solve competitive adsorption and improve catalytic performance. 展开更多
关键词 Urea production Competitive adsorption Doping heteronuclear metals TM-W_(18)O_(49)catalysts Density functional theory calculation
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Radiogenic geothermal systems of Bangka Island,Indonesia:Implications of high heat production and tectonic framework
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作者 Rahmat Nawi Siregar Mochamad Nukman +2 位作者 Kurnia Setiawan Widana Agung Harijoko Sismanto Sismanto 《Energy Geoscience》 EI 2024年第4期89-107,共19页
The presence of geothermal manifestation in Bangka Island(Southeast Sumatra,Indonesia)with the absence of Quaternary volcanic activity and also relatively low seismicity events has raised intriguing questions on the c... The presence of geothermal manifestation in Bangka Island(Southeast Sumatra,Indonesia)with the absence of Quaternary volcanic activity and also relatively low seismicity events has raised intriguing questions on the control of the geothermal system in this area.As the regional tectonic setting of Indonesia volcanic geothermal systems has been known,that of non-volcanic geothermal systems such as radiogenic system become an issue to be investigated.This study reports the geochemistry and petrography analysis of Triassic granite related to radiogenic production at the vicinity of hot springs in Bangka Island.Surface temperatures of the Bangka hot springs range from 37 to 70.7 and pH values vary between 5.6 and 7.5.These hot springs are discharging either in close to massive granite bodies or occur in between two major NE-SW striking faults zones,i.e.,Pemali fault and Payung fault.Our results indicate the average radiogenic heat production of Late Triassic Klabat granite in the northern area ranges from 28.5 to 38.34μWm^(-3)and the southern area ranges from 28.3 to 49.5μWm^(-3).In comparison to similar granite belt located in Malaysia,heat production of granitoid in Bangka hot springs is four times higher,possibly due to their different granite origins. 展开更多
关键词 Radiogenic geothermal Radiogenic heat production GRANITE Radioactive element
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The Correlation between the Power Quality Indicators and Entropy Production Characteristics of Wind Power+Energy Storage Systems
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作者 Caifeng Wen Boxin Zhang +3 位作者 Yuanjun Dai Wenxin Wang Wanbing Xie Qian Du 《Energy Engineering》 EI 2024年第10期2961-2979,共19页
Power quality improvements help guide and solve the problems of inefficient energy production and unstable power output in wind power systems.The purpose of this paper is mainly to explore the influence of different e... Power quality improvements help guide and solve the problems of inefficient energy production and unstable power output in wind power systems.The purpose of this paper is mainly to explore the influence of different energy storage batteries on various power quality indicators by adding different energy storage devices to the simulated wind power system,and to explore the correlation between systementropy generation and various indicators,so as to provide a theoretical basis for directly improving power quality by reducing loss.A steady-state experiment was performed by replacing the wind wheel with an electric motor,and the output power qualities of the wind power systemwith andwithout energy storagewere compared and analyzed.Moreover,the improvement effect of different energy storage devices on various indicatorswas obtained.Then,based on the entropy theory,the loss of the internal components of the wind power system generator is simulated and explored by Ansys software.Through the analysis of power quality evaluation indicators,such as current harmonic distortion rate,frequency deviation rate,and voltage fluctuation,the correlation between entropy production and each evaluation indicator was explored to investigate effective methods to improve power quality by reducing entropy production.The results showed that the current harmonic distortion rate,voltage fluctuation,voltage deviation,and system entropy production are positively correlated in the tests and that the power factor is negatively correlated with system entropy production.In the frequency range,the frequency deviationwas not significantly correlated with the systementropy production. 展开更多
关键词 Wind power system entropy production system losses power quality indexes battery energy storage
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Crosstalk between degradation and bioenergetics: how autophagy and endolysosomal processes regulate energy production
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作者 Angelid Pabon Jagannatham Naidu Bhupana Ching-On Wong 《Neural Regeneration Research》 SCIE CAS 2025年第3期671-681,共11页
Cells undergo metabolic reprogramming to adapt to changes in nutrient availability, cellular activity, and transitions in cell states. The balance between glycolysis and mitochondrial respiration is crucial for energy... Cells undergo metabolic reprogramming to adapt to changes in nutrient availability, cellular activity, and transitions in cell states. The balance between glycolysis and mitochondrial respiration is crucial for energy production, and metabolic reprogramming stipulates a shift in such balance to optimize both bioenergetic efficiency and anabolic requirements. Failure in switching bioenergetic dependence can lead to maladaptation and pathogenesis. While cellular degradation is known to recycle precursor molecules for anabolism, its potential role in regulating energy production remains less explored. The bioenergetic switch between glycolysis and mitochondrial respiration involves transcription factors and organelle homeostasis, which are both regulated by the cellular degradation pathways. A growing body of studies has demonstrated that both stem cells and differentiated cells exhibit bioenergetic switch upon perturbations of autophagic activity or endolysosomal processes. Here, we highlighted the current understanding of the interplay between degradation processes, specifically autophagy and endolysosomes, transcription factors, endolysosomal signaling, and mitochondrial homeostasis in shaping cellular bioenergetics. This review aims to summarize the relationship between degradation processes and bioenergetics, providing a foundation for future research to unveil deeper mechanistic insights into bioenergetic regulation. 展开更多
关键词 AUTOPHAGY BIOENERGETICS endolysosome energy production GLYCOLYSIS metabolic reprogramming MITOCHONDRIA
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Construction of a Virtual Simulation Practice Teaching System of the Chemical Industry Under the Background of Integration of Production and Education
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作者 Lixia Wang 《Journal of Contemporary Educational Research》 2024年第5期103-109,共7页
With the development of the integration of production and education,chemical engineering and technology education is facing many new challenges and opportunities.The construction of a chemical virtual simulation pract... With the development of the integration of production and education,chemical engineering and technology education is facing many new challenges and opportunities.The construction of a chemical virtual simulation practice teaching system under the background of integration of production and education aims to improve students’learning efficiency and innovation ability with the help of virtual simulation technology,so as to meet the needs of future industrial development.This paper discusses the significance of the construction of the system,analyzes the difficulties and challenges that may be encountered in the construction process,and evaluates the effective strategies to strengthen the construction of the system.Through the introduction of virtual simulation technology,students can improve their practical skills and innovation ability,and better adapt to the development needs of industrialization and informatization. 展开更多
关键词 Integration of production and education Chemical virtual simulation practice Teaching system
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Trend in seasonal amplitude of northern net ecosystem production:Simulated results from IAP DGVM in CAS-ESM2
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作者 Jiawen Zhu Xiaodong Zeng 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第2期45-51,共7页
北方陆地净生态系统生产力(NEP)具有明显的季节变化特征,这是大气CO_(2)季节变化的关键驱动.研究这些碳循环过程并理解潜在的驱动因素是气候研究的一个关键问题.本文利用第二代中国科学院地球系统模式(CAS-ESM2)中的全球植被动态模型(IA... 北方陆地净生态系统生产力(NEP)具有明显的季节变化特征,这是大气CO_(2)季节变化的关键驱动.研究这些碳循环过程并理解潜在的驱动因素是气候研究的一个关键问题.本文利用第二代中国科学院地球系统模式(CAS-ESM2)中的全球植被动态模型(IAPDGVM),研究了1990-2014年北方NEP(40°-90°N)的季节振幅及其变化趋势.在初始化试验的基础上,本文开展了一个控制试验来评估模拟的北方NEP季节幅度的变化趋势,同时开展了三个敏感性试验来研究气候和大气CO_(2)的贡献.结果表明:1990-2014年,模拟的北方NEP季节振幅显著增加,趋势为9.69万吨碳/月/年,这主要是由于最大NEP增加所致.当分别排除CO_(2)施肥效应和气候效应时,上述增加趋势大大减弱.这些显著的减少表明大气CO_(2)和气候变化对北方NEP的季节性振幅有重要影响.尽管模式存在不确定性,但这些结果有利于进一步提升IAPDGVM对陆地碳循环的精确模拟,也为CAS-ESM研究碳-气候相互作用的应用提供了重要参考. 展开更多
关键词 净生态系统生产力 北方陆地生态系统 季节变化幅度 CO_(2)施肥效应 气候效应
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Construction of Land Resource Security System for Core Grain Production Region in Henan Province 被引量:1
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作者 杨建波 卫华鹏 +1 位作者 王莉 邵红旗 《Agricultural Science & Technology》 CAS 2017年第12期2435-2439,共5页
To solve the contradiction between supply and demand of land, the con- struction of land resource security guarantee system is an important part to coordi- nate the economic development and cultivated land protection ... To solve the contradiction between supply and demand of land, the con- struction of land resource security guarantee system is an important part to coordi- nate the economic development and cultivated land protection in the core grain pro- duction region. Based on the deep analysis on the land resources characteristics and problems using the combined method of literature review method with qualita- tive and quantitative analysis, we constructed the land resource security system for different categories according to the land use principles of optimization, intensivism, improvement, and overall planning, and proposed the corresponding supporting mea- sures. The results showed that controlling the new increase, promoting the reclama- tion and improvement of land are the basis for land resource security, clearing the idle, improving the utilization rate of stock are the core of the efficient use of land resources, and establishing a unified urban and rural construction land market is the key to promoting the economical and intensive utilization of land resources, provid- ing scientific basis for the sustainable utilization of land resources in the core grain production regions. 展开更多
关键词 core grain production region Land resources Security system Con-struction
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Installation and Debugging of Auto-control System in Fruit Wine Production Line
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作者 方良材 黄卫萍 陈赶林 《Agricultural Science & Technology》 CAS 2014年第4期611-615,共5页
[Objective] The aim was to test the controlling effect of cleaning steriliza- tion system, material conveying system, and fermentation jar cooling system with equip- ments of fruit wine production line introduced in t... [Objective] The aim was to test the controlling effect of cleaning steriliza- tion system, material conveying system, and fermentation jar cooling system with equip- ments of fruit wine production line introduced in this study and its auto-control sys- tem field assembled and debugged. [Method] Based on controlling equipment and setting parameters on the configuration interface, the operation state of the control equipments could be real-time monitored and controlled with the help of configura- tion software. [Result] The result showed that the equipment system could reduce the temperature into 12 ℃ with the error of +0.5 ℃within 110 minutes when the fermentation temperature is set at 12 ℃ in real production. [Conclusion] The auto- control system of fruit wine production line was easy to be assembled and de- bugged to meet demands of different fruit wine productions. 展开更多
关键词 Fruit wine production line Control system INSTALLATION DEBUGGING
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Research on shipbuilding production logistics system combining MRP-Ⅱ with JIT
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作者 张庆英 岳卫宏 《Journal of Southeast University(English Edition)》 EI CAS 2007年第S1期151-155,共5页
Shipbuilding production management and logistics control are studied so as to find an advanced shipbuilding production logistics management style.The necessity and feasibility to integrate MRP-Ⅱ(manufacture resource ... Shipbuilding production management and logistics control are studied so as to find an advanced shipbuilding production logistics management style.The necessity and feasibility to integrate MRP-Ⅱ(manufacture resource planning)and JIT(just-in-time)are researched properly following the comparison of MRP-Ⅱ and JIT and the analysis of shipbuilding production characteristics.A shipbuilding logistics system combining MRP-Ⅱ with JIT is set up and discussed according to a master production schedule(MPS),MRP and workshop-floor production control.The system is able to simplify the shipbuilding production plan,balance the workshop production,stabilize the supply,and inspire positivity and creativity so as to raise the shipbuilding production management level. 展开更多
关键词 shipbuilding industry production logistics MRP-Ⅱ(manufacture resource planning) JIT(just-in-time)
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Optimum Investment Policies for Diagnostic Equipment under a Limited Budget in Multistage Production Systems
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作者 Banhan Lila W.J. Kennedy(Industrial Engineering Department, Clemson University, SC., USA.) 《International Journal of Plant Engineering and Management》 1999年第Z1期475-489,共15页
Diagnostic equipment can contribute significantly to production and quality.Maintenance budget however is limited so that having a systematic method for allocating part ofit to diagnostic equipment is of great potenti... Diagnostic equipment can contribute significantly to production and quality.Maintenance budget however is limited so that having a systematic method for allocating part ofit to diagnostic equipment is of great potential value. In this paper, a deterministic dynamicprogramming model for assisting in determining the optimum policy for investment in diagnosticequipment for multistage production systems is developed. The optimum pelticy is determined interms of the amount of equipment used at each stage of production and yields the maximumreturn for the entire system. 展开更多
关键词 INVESTMENT BUDGET DIAGNOSTIC equipment MULTISTAGE production system.
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How Could Agricultural Land Systems Contribute to Raise Food Production Under Global Change? 被引量:23
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作者 WU Wen-bin YU Qiang-yi +3 位作者 Verburg H Peter YOU Liang-zhi YANG Peng TANG Hua-jun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第7期1432-1442,共11页
To feed the increasing world population, more food needs to be produced from agricultural land systems. Solutions to produce more food with fewer resources while minimizing adverse environmental and ecological consequ... To feed the increasing world population, more food needs to be produced from agricultural land systems. Solutions to produce more food with fewer resources while minimizing adverse environmental and ecological consequences require sustainable agricultural land use practices as supplementary to advanced biotechnology and agronomy. This review paper, from a land system perspective, systematically proposed and analyzed three interactive strategies that could possibly raise future food production under global change. By reviewing the current literatures, we suggest that cropland expansion is less possible amid iferce land competition, and it is likely to do less in increasing food production. Moreover, properly allocating crops in space and time is a practical way to ensure food production. Climate change, dietary shifts, and other socio-economic drivers, which would shape the demand and supply side of food systems, should be taken into consideration during the decision-making on rational land management in respect of sustainable crop choice and allocation. And ifnally, crop-speciifc agricultural intensiifcation would play a bigger role in raising future food production either by increasing the yield per unit area of individual crops or by increasing the number of crops sown on a particular area of land. Yet, only when it is done sustainably is this a much more effective strategy to maximize food production by closing yield and harvest gaps. 展开更多
关键词 agricultural land systems food production expansion ALLOCATION INTENSIFICATION global change
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Towards sustainable intensification of apple production in China—Yield gaps and nutrient use effi ciency in apple farming systems 被引量:22
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作者 WANG Na Joost Wolf ZHANG Fu-suo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第4期716-725,共10页
China is in a dominant position in apple production globally with both the largest apple growing area and the largest export of fresh apple fruits. However, the annual productivity of China's apple is significantly l... China is in a dominant position in apple production globally with both the largest apple growing area and the largest export of fresh apple fruits. However, the annual productivity of China's apple is significantly lower than that of other dominant apple producing countries. In addition, apple production is based on excessive application of chemical fertilizers and the nutrient use efficiency (especially nitrogen) is therefore low and the nutrient emissions to the environment are high. Apple production in China is considerably contributes to farmers' incomes and is important as export product. There is an urgent need to enhance apple productivity and improve nutrient use efficiencies in intensive apple production systems in the country. These can be attained by improved understanding of production potential, yield gaps, nutrient use and best management in apple orchards. To the end, priorities in research on apple production systems and required political support are described which may lead to more sustainable and environmental-friendly intensification of apple production in China. 展开更多
关键词 apple production China environmental problems nutrient use efficiency potential yield sustainableintensification yield gaps
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Improving Geese Production Performance in “Goose-Fish” Production System by Competitive Reduction of Pathogenic Bacteria in Pond Water 被引量:22
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作者 YANG Xi-wen LIU Li +3 位作者 JIANG Dan-li WANG Cong-li SUN Ai-dong SHI Zhen-dan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第6期993-1001,共9页
This study investigated whether competitive reduction of pathogenic bacteria growth in pond water alleviates lipopolysaccharide (LPS) contamination and improves geese production performances in the "goose-fish" pr... This study investigated whether competitive reduction of pathogenic bacteria growth in pond water alleviates lipopolysaccharide (LPS) contamination and improves geese production performances in the "goose-fish" production system, thereby providing the potential for an improved technique for ecological water fowl production. In the first experiment, 240 Magang goslings of 15-d age were randomly and equally allocated into 16 "yard and pond" pens using a 2-2 factorial design with 4 replications per treatment. In the 55-d experimental period, the goslings received 2 main treatments: supplementation of Bacillus subtilis spores in the feed and addition of photosynthetic bacteria (PSB) to the pond water. Both B. subtilis spores and PSB treatments significantly suppressed water counts of Gram-negative bacteria Escherichia coli, Salmonella and Shigella, and LPS concentrations in pond water and in gosling blood (P〈0.05). As the result, the two treatments significantly improved gosling weight gain and carcass quality, marked by enhanced breast and leg muscle percentages and reduced subcutaneous fat proportions (P〈0.05). Moreover, the improved effects of B. subtilis spores and PSB treatments were additive. In the second experiment, 1 160 adult geese were induced to start egg laying from May throughout the summer months. The geese were separated equally into control and experimental flocks to fit into 2 integration production units, with a density of 1 bird m-2 meter on pond water. Experimental flock geese were treated with B. subtilis spores in feed and PSB in the pond water for the duration of the study. Such treatment combination significantly depressed the growth of E. coli, Salmonella and Shigella in the pond water and reduced LPS concentrations both in pond water and in geese blood (P〈0.01). As a result, egg fertility, fertile and set egg hatchabilities were all improved in the treated flock. Results from both growing goslings and breeding geese demonstrated that water bacteria pollution can be competitively reduced by supplementation with B. subtilis spores via the feed and addition of PSB in pond water, each of which reduces LPS contamination to geese and improves production performances. Micro- ecological agents such as B. subtilis spores and PSB improve water quality and provide a simple ecological technique for the "water fowl-fish" integrative production system. 展开更多
关键词 bacteria growth LIPOPOLYSACCHARIDE geese production performance B. subtilis spores photosyntheticbacteria
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Raising on Water Stocking Density Reduces Geese Reproductive Performances via Water Bacteria and Lipopolysaccharide Contaminations in “Geese-Fish” Production System 被引量:23
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作者 JIANG Dan-li LIU Li +3 位作者 WANG Cong-li CHEN Fang SUN Ai-dong SHI Zhen-dan 《Agricultural Sciences in China》 CAS CSCD 2011年第9期1459-1466,共8页
This study was carried out to unravel the mechanism of reductions in production performances in high stocking density geese flocks during summer months in "geese-fish" production system. Experiment 1 observed the wa... This study was carried out to unravel the mechanism of reductions in production performances in high stocking density geese flocks during summer months in "geese-fish" production system. Experiment 1 observed the water bacterial growth, lipopolysaccharde concentrations in water and geese blood, and geese reproductive performances from summer to winter, in two flocks with varying on water stocking densities. Results showed that counts of total bacteria, Escherichia coli and Salmonella in water, as well as water and geese plasma LPS concentrations, exhibited a tendency decreasing from the highest levels in summer, to intermediate levels in autumn, and to the lowest values in winter. Such seasonal decreases in bacteria and LPS concentrations were associated with similar seasonal decreases in embryo mortality during incubation. In addition, embryos dead or showing development retardation by day 25 of incubation contained copious LPS in allantoic fluid, in contrast to the negligible amount in normal developing embryos. Raising on water stocking density elevated bacteria counts, LPS concentrations in water and geese plasma, and decreased egg fertility but increased embryo mortality during incubation. In experiment 2, exogenous LPS treatment to the geese depressed egg laying, reduced egg hatchability, caused sickness behavior in the goslings hatched. In experiment 3, exogenous LPS directly administered to day 8 and 18 embryos during incubation dose dependently increased mortality and decreased hatchability, and caused sickness behavior in the goslings hatched. It is concluded that the raising on water geese stocking density stimulates pathogenic bacteria growth in water, which via LPS contamination impaires embryo development in incubation and therefore reduces geese reproductive performance and gosling quality during the hot summer months. 展开更多
关键词 water bacteria growth LIPOPOLYSACCHARIDE production performances GEESE
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Herbicide resistance: Development of wheat production systems and current status of resistant weeds in wheat cropping systems 被引量:6
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作者 Sridevi Nakka Mithila Jugulam +1 位作者 Dallas Peterson Mohammad Asif 《The Crop Journal》 SCIE CAS CSCD 2019年第6期750-760,共11页
Herbicide resistance in crops has extended the scope of herbicide applications to control weeds. The introduction of herbicide resistant crops resulted in a major shift in the way that herbicides are used in many crop... Herbicide resistance in crops has extended the scope of herbicide applications to control weeds. The introduction of herbicide resistant crops resulted in a major shift in the way that herbicides are used in many crops, but not necessarily increased the prevalence of herbicide use, especially in wheat. Wheat is one of the most widely grown crops in the world and currently only two major herbicide-resistant wheat groups have been commercialized to manage weeds in a cost-effective manner. However, sustainable wheat production is threatened by the expanding occurrence of herbicide-resistant weed populations with limited efforts to discover new herbicide molecules. Selective control of certain problematic weeds in wheat was impossible until development and introduction of the technologies, Clearfield and Co AXium Production Systems. However, the current limitations of reliance on specific herbicides and evolution of resistant weeds mandate precautions and considerations when using these systems to prevent the loss of existing herbicide resources and continue sustainable wheat production. The focus of this review is to provide an overview of natural pre-existing herbicide resistance and development of herbicide-resistant technologies in wheat. The mechanisms of resistance to herbicides in wheat as well as the weed populations in wheat cropping systems, and implications for weed management are discussed. 展开更多
关键词 Clearfield Coaxium CYTOCHROME P450s GSTS HERBICIDE RESISTANCE WHEAT production systemS
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Extraction of Theanine from Waste Liquid of Tea Polyphenol Production in Aqueous Two-phase Systems with Cationic and Anionic Surfactants 被引量:8
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作者 张军伟 王艳 彭奇均 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第1期31-36,共6页
Extraction of theanine from waste liquid of tea polyphenol production was studied in aqueous surfactanttwo-phase system (ASTP) with cationic surfactant (CTAB) and anionic surfactant (SDS). Results indicate that ... Extraction of theanine from waste liquid of tea polyphenol production was studied in aqueous surfactanttwo-phase system (ASTP) with cationic surfactant (CTAB) and anionic surfactant (SDS). Results indicate that the region of ASTP is narrow and there is only a two-phase region of cationic surfactant. The increase in concentrations of NaBr and Na2SO4 are beneficial to the formation of ASTP. Theanine concentration in the bottom phase increases with increasing concentration of theanine, whereas the Partition coefficient and extraction rate only change a littlewhen the concentration of theanine is above 0.2 g.L-'. With the increase of SDS concentration, the phase ratio and the partition coefficient decrease, while the extraction efficiency of theanine increases and the concentration of theanine changes a little in the range from 2.4/7.5 to 2.8/7.2 for SDS/CTAB ratio. The temperature has a notable ef- fect on the concentration of theanine in the bottom phase, partition coefficient and extraction rate of theanine. The increase of waste liquid decreases the phase ratio, increases the concentration and extraction rate of theanine in the bottom ohase, since the orotein and the saccharide enter the bottom nhase with theanine. 展开更多
关键词 aqueous two-phase system SURFACTANT THEANINE waste liquid of tea polyphenol production EXTRACTION
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