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我国大豆生产波动动因分析——基于省际面板模型的实证研究 被引量:6
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作者 李维刚 张晓东 +1 位作者 宋继华 孙丹 《农业经济与管理》 CSSCI 北大核心 2023年第2期48-63,共16页
在我国大豆生产波动频繁的情况下,找出影响大豆单产、种植面积的影响因素是实现“提单产、稳面积”的首要举措。研究采用1999~2020年21个省份面板数据,在分析大豆单产、种植面积的变化趋势基础上,根据大豆单产增减趋势,把大豆产区划分... 在我国大豆生产波动频繁的情况下,找出影响大豆单产、种植面积的影响因素是实现“提单产、稳面积”的首要举措。研究采用1999~2020年21个省份面板数据,在分析大豆单产、种植面积的变化趋势基础上,根据大豆单产增减趋势,把大豆产区划分成增产区、减产区和波动区,采用改进的面板数据模型分别对三个产区的大豆单产和种植面积的影响因素进行实证分析。结果表明,机械化收割、产研结合、农药投入、小型拖拉机的投入是影响不同区域大豆单产的显著因素;机械化耕作是提升所有区域种植面积的显著因素,玉米种植面积、化肥投入、农药投入、灌溉条件、科研资金与人员投入、产研结合、机械化收割是影响不同区域大豆种植面积显著因素。根据分析,提出了相应政策建议。 展开更多
关键词 大豆生产 大豆单产 大豆种植面积
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高寒草地健康定量评价及生产——生态功能提升技术集成与示范 被引量:13
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作者 董全民 周华坤 +7 位作者 施建军 董世魁 尚占环 汪新川 尚永成 赵之重 李世雄 王彦龙 《青海科技》 2018年第1期15-24,共10页
本项目以青海省高寒草地(高寒草甸、高寒草原)为研究对象,针对高寒草地健康定量评价及生产—生态功能提升的科学问题及技术需求,统筹考虑草地生态系统的特殊性和生态—生产—生活承载力,从人—草—畜—环境的综合系统出发,以草地生态保... 本项目以青海省高寒草地(高寒草甸、高寒草原)为研究对象,针对高寒草地健康定量评价及生产—生态功能提升的科学问题及技术需求,统筹考虑草地生态系统的特殊性和生态—生产—生活承载力,从人—草—畜—环境的综合系统出发,以草地生态保护为前提,以发展草地生态畜牧业为抓手,结合全国生态文明先行区、全国草地生态畜牧业示范区、三江源区二期工程建设以及三江源国家公园体制试点方案,开展了高寒草地健康评价及生产—生态功能衰退与结构失调的整合提升研究。通过机制揭示—技术研发—示范应用的全链条设计和一体化实施,在实验点、示范区和区域3个层面上结合高寒草地健康评价与退化草地治理工程,可视化诊断了高寒草地健康状态,定量分析了高寒草地退化成因及因子贡献率,揭示了退化演替的生态过程及其特征,阐明了退化高寒草地生态恢复的生理生态学及繁殖生态学机理,驯化选育出适宜高寒草地恢复治理的牧草新品种,研发出不同类型退化草地生态—生产功能提升技术、高寒人工草地生产—生态群落稳定性调控技术,创建了人工草地分类经营与管理技术模式,对退化草地修复治理进行信息化管理,量化了不同恢复措施的生产、生态效益,系统开展了技术体系的示范与推广,兼顾基础理论探析、健康诊断评价、信息技术管理、关键技术突破及创新模式集成,形成适宜该地区的生产—生态功能提升技术体系,为高寒草地生态系统管理和生态畜牧业产业经济发展提供科学依据、技术支撑和示范样板。 展开更多
关键词 高寒草地 退化 分类分级 健康评价 生产--生态功能
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Anomaly Detection Method Using Feature Reconstruction Based Knowledge Distillation
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作者 ZHU Xin-yu SI Zhan-jun ZHANG Ying-xue 《印刷与数字媒体技术研究》 CAS 北大核心 2024年第4期115-124,236,共11页
In recent years,anomaly detection has attracted much attention in industrial production.As traditional anomaly detection methods usually rely on direct comparison of samples,they often ignore the intrinsic relationshi... In recent years,anomaly detection has attracted much attention in industrial production.As traditional anomaly detection methods usually rely on direct comparison of samples,they often ignore the intrinsic relationship between samples,resulting in poor accuracy in recognizing anomalous samples.To address this problem,a knowledge distillation anomaly detection method based on feature reconstruction was proposed in this study.Knowledge distillation was performed after inverting the structure of the teacher-student network to avoid the teacher-student network sharing the same inputs and similar structure.Representability was improved by using feature splicing to unify features at different levels,and the merged features were processed and reconstructed using an improved Transformer.The experimental results show that the proposed method achieves better performance on the MVTec dataset,verifying its effectiveness and feasibility in anomaly detection tasks.This study provides a new idea to improve the accuracy and efficiency of anomaly detection. 展开更多
关键词 Feature Reconstruction Anomaly Detection Distillation Mechanism Industrial Production
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Potentials and Challenges of Carbon Knowledge Graph in Sustainable Textile Production for Carbon Traceability:A Review
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作者 BAO Jinsong WU Tao LI Jie 《Journal of Donghua University(English Edition)》 CAS 2024年第4期349-364,共16页
Textile production has received considerable attention owing to its significance in production value,the complexity of its manufacturing processes and the extensive reach of its supply chains.However,textile industry ... Textile production has received considerable attention owing to its significance in production value,the complexity of its manufacturing processes and the extensive reach of its supply chains.However,textile industry consumes substantial energy and materials and emits greenhouse gases that severely harm the environment.In addressing this challenge,the concept of sustainable production offers crucial guidance for the sustainable development of the textile industry.Low-carbon manufacturing technologies provide robust technical support for the textile industry to transition to a low-carbon model by optimizing production processes,enhancing energy efficiency and minimizing material waste.Consequently,low-carbon manufacturing technologies have gradually been implemented in sustainable textile production scenarios.However,while research on low-carbon manufacturing technologies for textile production has advanced,these studies predominantly concentrate on theoretical methods,with relatively limited exploration of practical applications.To address this gap,a thorough overview of carbon emission management methods and tools in textile production,as well as the characteristics and influencing factors of carbon emissions in key textile manufacturing processes is presented to identify common issues.Additionally,two new concepts,carbon knowledge graph and carbon traceability,are introduced,offering strategic recommendations and application directions for the low-carbon development of sustainable textile production.Beginning with seven key aspects of sustainable textile production,the characteristics of carbon emissions and their influencing factors in key textile manufacturing process are systematically summarized.The aim is to provide guidance and optimization strategies for future emission reduction efforts by exploring the carbon emission situations and influencing factors at each stage.Furthermore,the potential and challenges of carbon knowledge graph technology are summarized in achieving carbon traceability,and several research ideas and suggestions are proposed. 展开更多
关键词 sustainable textile production carbon knowledge graph carbon traceability low-carbon development emission reduction
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Investigating the charge transfer mechanism of ZnSe QD/COF S-scheme photocatalyst for H_(2)O_(2) production by using femtosecond transient absorption spectroscopy
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作者 Yanyan Zhao Chunyan Yang +4 位作者 Shumin Zhang Guotai Sun Bicheng Zhu Linxi Wang Jianjun Zhang 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期258-269,共12页
Hydrogen peroxide(H_(2)O_(2))has gained widespread attention as a versatile oxidant and a mild disin-fectant.Here,an electrostatic self-assembly method is applied to couple ZnSe quantum dots(QDs)with a flower-like cov... Hydrogen peroxide(H_(2)O_(2))has gained widespread attention as a versatile oxidant and a mild disin-fectant.Here,an electrostatic self-assembly method is applied to couple ZnSe quantum dots(QDs)with a flower-like covalent organic framework(COF)to form a step-scheme(S-scheme)photocata-lyst for H_(2)O_(2)production.The as-prepared S-scheme photocatalyst exhibits a broad light absorption range with an edge at 810 nm owing to the synergistic effect between the ZnSe QDs and COF.The S-scheme charge-carrier transfer mechanism is validated by performing Fermi level calculations and in-situ X-ray photoelectron and femtosecond transient absorption spectroscopies.Photolumi-nescence,time-resolved photoluminescence,photocurrent response,electrochemical impedance spectroscopy,and electron paramagnetic resonance results show that the S-scheme heterojunction not only promotes charge carrier separation but also boosts the redox ability,resulting in enhanced photocatalytic performance.Remarkably,a 10%-ZnSe QD/COF has excellent photocatalytic H_(2)O_(2)-production activity,and the optimal S-scheme composite with ethanol as the hole scavenger yields a H_(2)O_(2)-production rate of 1895 mol g^(-1)h^(-1).This study presents an example of a high-performance organic/inorganic S-scheme photocatalyst for H_(2)O_(2)production. 展开更多
关键词 ZnSe quantum dot Covalent organic framework S-scheme heterojunction Carrier migration and separation H_(2)O_(2) production
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内观认知疗法对医学生焦虑水平、自我效能感和应对方式的干预及机制 被引量:2
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作者 王宇暄 毛富强 +4 位作者 彭悦悦 郭子熊 江珊 王书哲 王新琦 《中国健康心理学杂志》 2024年第5期781-787,共7页
目的:探究内观认知疗法对医学生焦虑水平、自我效能感和应对方式的影响,并考察医学生内观认知疗法干预、自我效能感、应对方式和焦虑水平间的关系,以期为医学生心理健康教育工作和NCT疗法的作用机制研究提供理论支持。方法:采用随机数... 目的:探究内观认知疗法对医学生焦虑水平、自我效能感和应对方式的影响,并考察医学生内观认知疗法干预、自我效能感、应对方式和焦虑水平间的关系,以期为医学生心理健康教育工作和NCT疗法的作用机制研究提供理论支持。方法:采用随机数字表法将70名符合筛选标准的研究对象随机分配到内观认知疗法组和心理健康教育组,每组35人。内观认知疗法组接受为期7天的内观认知疗法干预,心理健康教育组接受相同时间的常规心理健康教育,最终共68人完成试验(内观认知疗法组34人,心理健康教育组34人)。干预前后使用SAS、GSES、SCSQ量表对两组研究对象进行测评。结果:①干预前,内观认知疗法组与心理健康教育组在焦虑,自我效能感,积极和消极应对方式得分上均不存在显著差异。②干预后,内观认知疗法组焦虑得分显著降低(t=5.835;P<0.01),自我效能感和积极应对方式得分均显著升高(t=2.289,4.668;P<0.05),消极应对方式得分不存在显著差异,干预前后心理健康教育组在上述所有量表得分中均不存在显著差异。③干预后,内观认知疗法组自我效能感和积极应对方式得分显著高于心理健康教育组(t=2.653,3.122;P<0.01),焦虑得分显著低于心理健康组(t=2.562;P<0.05)。④中介效应检验方面,内观认知疗法既可以直接影响医学生焦虑水平(β=-0.293,95%CI=-3.755~0.008),也可以通过自我效能感的中介作用(β=-0.307,95%CI=-0.612~-0.028)、积极应对方式的中介作用(β=0.140,95%CI=-0.293~-0.004)及自我效能感和积极应对方式的链式中介作用(β=0.222,95%CI=-0.553~-0.022)间接影响医学生焦虑水平。结论:内观认知疗法是一种能够有效降低医学生焦虑水平的干预手段,既能直接缓解焦虑,也能通过提高医学生自我效能感水平,改善积极应对方式间接降低医学生焦虑水平。 展开更多
关键词 内观认知疗法 医学生 焦虑水平 应对方式 自我效能感
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Techno-economic and Environmental Assessments of SAF from Bioamss:An Review
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作者 MAHMOOD T.M.N.Saeed PANG Shusheng CHEN Qiang 《林产化学与工业》 CAS CSCD 北大核心 2024年第5期29-51,共23页
This review presents a comprehensive techno-economic and life-cycle assessment of sustainable aviation fuel(SAF)production from biomass.The critical need for transitioning towards environmentally sustainable alternati... This review presents a comprehensive techno-economic and life-cycle assessment of sustainable aviation fuel(SAF)production from biomass.The critical need for transitioning towards environmentally sustainable alternatives for liquid fuel and aviation industry is first discussed.Key insights encompass the evolutionary progression of biofuel production from first-generation to second-generation biofuels,with a focus on utilizing non-food sources like woody biomass for enhanced sustainability.Available data from the literature on techno-economic assessments of various SAF production pathways are analyzed including production costs,conversion efficiency,and scalability.Moreover,results of lifecycle assessments associated with different SAF production pathways are presented,providing essential insights for decision-making processes.The challenges of scaling up woody biomass-based SAF production are discussed based on the assessment results,and recommendations are proposed to steer stakeholders towards a greener and more sustainable trajectory for aviation operations. 展开更多
关键词 sustainable aviation fuel woody biomass production costs minimum fuel selling price lifecycle assessment greenhouse gas emissions climate change
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土地利用-作物生产系统模拟研究进展 被引量:1
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作者 田小海 邹社校 《湖北农学院学报》 2001年第3期261-266,共6页
对土地利用—作物生产系统模拟研究方面的国内外最新进展进行了综述。主要讨论了近 2 0a来人们对土地利用—作物生产系统的系统性、层次性与动态性的认识 ,国内外已建立的模型及其评述 ,本领域研究的最新特点。最后对这一领域的研究进... 对土地利用—作物生产系统模拟研究方面的国内外最新进展进行了综述。主要讨论了近 2 0a来人们对土地利用—作物生产系统的系统性、层次性与动态性的认识 ,国内外已建立的模型及其评述 ,本领域研究的最新特点。最后对这一领域的研究进行了展望并对我国在这方面的研究策略提出了见解。 展开更多
关键词 土地利用--作物生产系统 模拟 模型 系统性 层次性 动态性
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茶园生产投入产出效益分析
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作者 方青 《茶叶通讯》 2000年第2期24-26,共3页
本文应用技术经济分析中柯布—道格拉斯生产函数法 ,对江苏省高淳县青山茶场和安徽省郎溪县郎溪茶场的茶园生产系统的实际投入产出进行了综合分析 ,并分别对两场在茶园采摘用工投入、肥料和农药投入及经营规模上的决策作了思考和建议。... 本文应用技术经济分析中柯布—道格拉斯生产函数法 ,对江苏省高淳县青山茶场和安徽省郎溪县郎溪茶场的茶园生产系统的实际投入产出进行了综合分析 ,并分别对两场在茶园采摘用工投入、肥料和农药投入及经营规模上的决策作了思考和建议。旨在从微观角度为优化配置。 展开更多
关键词 茶园生产 柯布--道格拉斯生产函数 生产效益
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From Less or No Waste Manufacturing and Cleaner Production to Recycle Economy -- A Review on the Theoretical Research and Practice of Ecological Enterprises in China 被引量:2
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作者 LiuYong 《Ecological Economy》 2005年第2期32-39,共8页
Based on systematical research on the conception evolution of ecological enterprise, theoretical and practical development of constructing ecological enterprise, the paper makes conclusion that ecological enter- prise... Based on systematical research on the conception evolution of ecological enterprise, theoretical and practical development of constructing ecological enterprise, the paper makes conclusion that ecological enter- prises are developing into a new stage in which governments are launching some pilot projects about construct- ing ecological enterprises. And after that, governments should make policies to spread construction of ecological enterprises, to construct ecological enterprises in legal system and conforming to the standard as soon as possibly. So that, the basic units of ecological economy that fit to the conditions of China will be set up. 展开更多
关键词 ecological enterprises cleaner production recycle economy the system of environment management implements of cleaner production.
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The Impact of Climate Change on China's Grain Market and Food Security-- A CGE Model Approach 被引量:1
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作者 Huang Delin Li Ximing +3 位作者 Li Xinxing Li Xiangyang Cai Songfeng Wang Chenggang 《Chinese Business Review》 2014年第7期427-441,共15页
This paper examines the impact of climate change on China's grain production and food security. The research is one of the four studies on future conditions of China's food production system under the influence of c... This paper examines the impact of climate change on China's grain production and food security. The research is one of the four studies on future conditions of China's food production system under the influence of climate change using numerical simulation methods, carried out under a national 973 project entitled "impacts of climate change on food systems in China and its adaptation". The other three studies focus on changes in cultivated land area and food production, while this study incorporates their grain yield results into a general equilibrium model to simulate future conditions of the grain market. Our simulation analysis arrives at the impact of climate change by comparing such economic variables as grain production, consumption, and GDP growth rate between a baseline scenario and two climate change scenarios. Our results are summarized as follows: (1) In 2050, the total grain production will reach 689.683 million tons--584.264 million tons of total grain consumption and 42.808 million tons of exports. Without considering losses and inventory demand, in 2050 China's grain supply and demand will remain well balanced, with a slight surplus expected. (2) Climate change is expected to benefit China's macro economy and individual sectors. In comparison with the baseline scenario of no climate change, real wage, real GDP, investment, household consumption, exports, and other macroeconomic indicators will rise under the climate change scenarios. As far as the agricultural, manufacturing, and service sectors are concerned, production, consumption, imports, and exports will each be favorably affected by climate change. (3) The favorable impact of climate change on China's macroeconomy and individual sectors under the high emissions scenario (A2) is stronger than that under the low emissions scenario (B2). (4) In the grain market, climate change is expected to increase supply, reduce imports, increase supply, and demand; and supply will increase more than demand does. All in all, if taking into the fertilization effect of CO2 account, climate change is expected to strengthen China's grain supply and safeguard food security. 展开更多
关键词 climate change Computable General Equilibrium (CGE) food security food production food consumption economic growth
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An Autonomous Electric Powered Tractor--Simulation of All Operations on a Swedish Dairy Farmagricultural m machinery. This s study investig gated the feasib bility of an au utonomous batte ery electric tra actor through simulation. The e
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作者 Jonas Engstrom Oscar Lagnelov 《Journal of Agricultural Science and Technology(A)》 2018年第3期182-187,共6页
For a conventional agricultural tractor the main environmental effects origina ates from the usage phase, more specifically from the diesel use and exhausts. To decre ease the environ nmental effect, it is vital to ... For a conventional agricultural tractor the main environmental effects origina ates from the usage phase, more specifically from the diesel use and exhausts. To decre ease the environ nmental effect, it is vital to find a substitute for fossil diesel as a fuel for agricultural machinery. This s study investig gated the feasib bility of an autonomous battery electric tractor through simulation. The simulated farm is an organic dairy farm of 200 ha with five crops in the crop rotation cycle and a traditional plough among the used implements. Based on the res sult from the simulation cost calculations, sensitivity analysi is and a limited life cycle analysis (LCA) was made. The results show that it is in theory possible to replace a conventional tractor (160 kW) with two autonomous battery powered machines (36 kW engine, 113 kWh battery) with 15% lower costs. Energy consumption would be red duced by 58% a and greenhouse gas emissions by 92% compared to diesel when energy consumption and greenhouse gas emissions from battery manufacturing were included. Today the technology for autonom mous control is under fast development, but there are yet no systems on the market that can handle all machinery tasks like assumed in this study. Challenges yet to solve are , among others, legislative, relevant sensors, logistics and fleet management. Further rese earch is needed to verify the results in practical farming. 展开更多
关键词 AUTONOMOUS agriculture ELECTRIC battery TRACTOR farming fossil free sustainable
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Analysis of Waste in the Production of Concrete Blocks---A Case Study in the Goias Industry
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作者 Tatiana Gondim do Amaral Weslley M. Cruz Jose R. Perim 《Journal of Civil Engineering and Architecture》 2015年第8期926-937,共12页
An ever more demanding consumer market and the need for companies to be more competitive have led organizations to try to eliminate waste. This research is a case study which presents a proposal for intervention in or... An ever more demanding consumer market and the need for companies to be more competitive have led organizations to try to eliminate waste. This research is a case study which presents a proposal for intervention in order to improve performance of a pre-cast concrete block factory in outer Goihnia. As a first step, waste in the production process was identified through analysis of data on time involved in each step of the process. Then, applying the concepts of lean production, a list of activities was drawn up with a view to eliminating non-value-added work, identifying waste, decreasing cycle time, streamlining the production process and increasing the flexibility and transparency of the process. From the results, it was possible to identify the sources of waste and provide management with information for strategic decisions about production. Finally, various suggestions were made with a view to eliminating or mitigating bottlenecks in the production process. 展开更多
关键词 Lean production WASTE concrete blocks continuous improvement.
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Wheat Chaff and Waste of Molasses Dates Production--New Surfaces for Removal of Biological Pollutants from Aqueous Solutions
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作者 Abdul- Muhsen Al-Haidari Saja S. Jabbar Al-Taweel Laith S. Jassim 《Journal of Chemistry and Chemical Engineering》 2013年第1期40-49,共10页
The adsorption ofEscherichia coli and Staphylococcus aureus on chaff and WMDP (waste of molasses dates production) has been studied. FTIR spectra were employed to investigate the adsorption ofEscherichia coli and St... The adsorption ofEscherichia coli and Staphylococcus aureus on chaff and WMDP (waste of molasses dates production) has been studied. FTIR spectra were employed to investigate the adsorption ofEscherichia coli and Staphylococcus aureus on surfaces. Adsorption of bacteria resulted in obvious shifts of some infrared bands of adsorbents. The adsorption isotherms ofEscherichia coli on two surfaces and Staphylococcus aureus on WMDP, are of L-curve type according to Giles classification. However, type H isotherm was observed in the adsorption of S. aureus on chaff. The adsorption isotherms of bacteria on the examined adsorbents conformed to the Langmuir and Temkin equations. The adsorption of bacteria was studied at different temperatures (10, 25 and 40 ℃), the thermodynamic parameters (AH, AS and AG) have also been calculated and it has been found that the adsorption process of bacteria was exothermic in nature. The number of bacteria adsorbed on surfaces was decreased with the increase of sodium chloride concentration. The amount of bacteria cells adsorbed was increased in the presence of different cations and followed the sequence: FeCl3 〉 CaCl2 〉 KCl 〉 NaCl. The pseudo-first order and pseudo-second order models for describing the kinetic data were applied and it was found that the process was well described by pseudo-second order model. The desorption studies indicated that the bacteria were strongly retained by two adsorbents. 展开更多
关键词 CHAFF WMDP bacteria adsorption water treatment
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Innovation--the Key Factor in Entrepreneurial Cycles
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作者 Robert Molnar Drago Soldat 《Journal of Mechanics Engineering and Automation》 2012年第1期63-67,共5页
This paper focuses on the innovation as a key factor in entrepreneurial cycles particularly in those who deal with production. Taking into the consideration the whole entrepreneurial cycle, the innovation is the most ... This paper focuses on the innovation as a key factor in entrepreneurial cycles particularly in those who deal with production. Taking into the consideration the whole entrepreneurial cycle, the innovation is the most sensitive factor that determines the products giving to them the "soul" and in most cases separating successful from unsuccessful ones on the market. In the era of global market, competitiveness became one of the most important factors for each company. Within an enterprise, the engineers are those who are qualified and responsible to take care about the competitiveness of the products that company produce. They have to be introduced not just about the technology in sense of "how to made smt.", but even rather "bow to make the better product than others". "Better" could be involved in product various characteristics as quality, functionality, durability and any other ones which will convince the customer to buy it. The engineers should be more focused on the "value" involved in the product rather than on its "materialization", simply because the customers buy the value for him/her. By neglecting innovation, companies become just a simple economy subjects, without entrepreneurial elements, losing competitiveness and endanger their future. In long-term perspective, the permanent innovations implemented in the products and services as well as in the production process enable companies to became or remain competitive on the market. 展开更多
关键词 INNOVATION COMPETITIVENESS PRODUCT production process entrepreneurship.
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An Empirical Research of Producer Services' Cluster Development To Regional Industrial Structure Optimization And Upgrading --Based on the Research of 16 central cities' Panel Data in Yangtze River Delta
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作者 LI Zhen-bo ZHANG ming-dou 《International Journal of Technology Management》 2015年第10期80-87,共8页
Based on the 16 central cities' Panel Data in Yangtze River Delta, location quotient index is used in this paper to measure and analyze the current cluster situation of producer services in Yangtze River Delta, fixed... Based on the 16 central cities' Panel Data in Yangtze River Delta, location quotient index is used in this paper to measure and analyze the current cluster situation of producer services in Yangtze River Delta, fixed effects model of Panel Data model is also used in this paper, and the industrial structure is taken as the dependent variable, while the core explanatory variables is the degree of producer services' cluster development, which is calculated by location quotient, moreover, three control variables introduced in this paper and they are technology advantage, education level and R&D spending, and the mentioned above is to empirically study the impacts of producer services' cluster development to the regional industrial structure. As a result, producer services' cluster development has a significant positive role in promoting the regional industrial structure optimization and upgrading, though the extent is not yet a big push and is still to be further strengthened. In this paper, it has provided a strong evidence that under China' s new normal economy, producer services is badly needed to promote regional industrial structure, and finally it makes specific suggestions based on the current cluster situation of producer services in Yangtze River Delta. 展开更多
关键词 producer services location quotient regional industrial structure optimization and upgrading
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“集中生产主剂,分散罐装饮料”可行性探讨(上)
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作者 老狼 《中国果菜》 2001年第3期28-28,共1页
关键词 饮料工业 生产模式 “集中生产主剂--分散罐装饮料” 可行性分析
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Realism of Movie Arts and Ecology folk cultural heritage in Southern Shaanxi Province --Taking the real movie "Lang singing folk songs in the door" for example
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作者 Jun Su 《International Journal of Technology Management》 2014年第10期22-24,共3页
The real movie "Lang singing folk songs in the door" is the triangle love story among Xiao Yang, Feng Gang and Zhang Xuefeng. the three characters are the main line. folk songs in Nan Kang Ziyang of Shaanxi are the ... The real movie "Lang singing folk songs in the door" is the triangle love story among Xiao Yang, Feng Gang and Zhang Xuefeng. the three characters are the main line. folk songs in Nan Kang Ziyang of Shaanxi are the carrier, full of musical charm and cultural values. Folk songs, and love reveal the tragic loss and suffering in modern youth life-changing period, and reflect the gap between ideal and reality. Movie inspires people, developing and upholding heritage of folk music and cultural needs the whole community' s concern and support, a cavity blood alone and personal ideals are not enough, only rely on social groups and cultural media, can Southern folk ecological culture be in sustainable development, and fly out of the country to the world. 展开更多
关键词 "Lang singing folk songs in the door" artistic expression Southern folk songs cultural heritage
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不同植物生长调节剂对冬小麦生长及产量的影响 被引量:3
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作者 张飞雪 陈峰 +2 位作者 张书红 马延东 刘锐杰 《肥料与健康》 CAS 2023年第6期58-61,66,共5页
为考察不同植物生长调节剂对农作物生长状况及产量的影响,以氨基寡糖素、复硝酚钠和胺鲜酯为处理药剂,以复合肥(18-15-12)为药剂载体,于冬小麦播种前底施于土壤,测定了不同生育时期冬小麦的株高、主根长、须根数、分蘖数、叶片数、顶节... 为考察不同植物生长调节剂对农作物生长状况及产量的影响,以氨基寡糖素、复硝酚钠和胺鲜酯为处理药剂,以复合肥(18-15-12)为药剂载体,于冬小麦播种前底施于土壤,测定了不同生育时期冬小麦的株高、主根长、须根数、分蘖数、叶片数、顶节长、穗长、旗叶长、颖果数等指标。结果表明:氨基寡糖素在冬小麦前期能促苗生根,中期能促叶、增加分蘖数,提高冬小麦产量;复硝酚钠主要表现在中后期能促进冬小麦株高和旗叶的生长;胺鲜酯在冬小麦前期对茎叶、须根数,在中期对顶节长、颖果数具有促进作用,但后期对顶节长、旗叶长和颖果数有抑制作用;复硝酚钠和胺鲜酯均会降低冬小麦产量。 展开更多
关键词 植物生长调节剂 冬小麦 氨基寡糖素 复硝酚钠 胺鲜酯
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Interannual Variation in Terrestrial Ecosystem Carbon Fluxes in China from 1981 to 1998 被引量:34
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作者 曹明奎 陶波 +2 位作者 李克让 邵雪梅 Stephen D PRIENCE 《Acta Botanica Sinica》 CSCD 2003年第5期552-560,共9页
A dynamic biogeochemical model was used to estimate the responses of China's terrestrial net primary productivity (NPP), soil heterotrophic respiration (HR) and net ecosystem productivity (NEP) to changes in clima... A dynamic biogeochemical model was used to estimate the responses of China's terrestrial net primary productivity (NPP), soil heterotrophic respiration (HR) and net ecosystem productivity (NEP) to changes in climate and atmospheric CO2 from 1981 to 1998. Results show that China's total NPP varied between 2.89 and 3.37 Gt C/a and had an increasing trend by 0.32% per year, HR varied between 2.89 and 3.21 Gt C/a and grew by 0.40% per year, Annual NEP varied between -0.32 and 0.25 Gt C but had no statistically significant interannual trend. The positive mean NEP indicates that China's terrestrial ecosystems were taking up carbon with a total carbon sequestration of 1.22 Gt C during the analysis period. The terrestrial NEP in China related to climate and atmospheric CO2 increases accounted for about 10% of the world's total and was similar to the level of the United States in the same period. The mean annual NEP for the analysis period was near to zero for most of the regions in China, but significantly positive NEP occurred in Northeast China Plain, the southeastern Xizang (Tibet) and Huang-Huai-Hai Plain, and negative NEP occurred in the Da Hinggan Mountains, Xiao Hinggan Mountains, Loess Plateau and Yunnan-Guizhou Plateau. China's climate at the time was warm and dry relative to other periods, so the estimated NEP is probably lower than the average level. China's terrestrial NEP may increase if climate becomes wetter but is likely to continue to decrease if the present warming and drying trend sustains. 展开更多
关键词 China net primary productivity (NPP) soil heterotrophic respiration (HR) net ecosystem productivity (NEP) climate change
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