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Clean Coal &High Carbon Efficiency Energy Engineering
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作者 Stefan Petters Kalvin Tse 《Journal of Power and Energy Engineering》 2015年第4期348-355,共8页
Today we live in a world of Hydrocarbon Energy Carriers, where Carbon is always used as a Carrier for Hydrogen 1) Biomass (CH1.44O0.66 or C6H12O6);2) Natural Gas [NG] (CH4);3) Water Gas [C+H2O];4) Gasoline (C6H12, C7H... Today we live in a world of Hydrocarbon Energy Carriers, where Carbon is always used as a Carrier for Hydrogen 1) Biomass (CH1.44O0.66 or C6H12O6);2) Natural Gas [NG] (CH4);3) Water Gas [C+H2O];4) Gasoline (C6H12, C7H18, C8H18, etc.);5) Kerosene (C17H36, C18H38, C19H40, C20H42, C21H44, C22H46, etc.) and;6) Crude Oil. The Carbon aggregates are all storable and have worthwhile, logistically manageable energy densities. But whenever recovering Energy from the Carbon molarities, CO2 gets emitted into the atmosphere, while separate use of Hydrogen Energy contents carried by the Carbon moieties would just generate water vapor. Hydrogen is also the most important intermediary in Refineries, hydrogenating lower grade Hydrocarbons into higher potencies, or for removing Sulfur by the formation of Hydrogen Sulfur, that can be dissociated after its segregation from the Hydrocarbon products. But most of the internal Hydrogen yields in Refineries today is used for onsite production of Ammonia as a basis for Energy fertilizers in high performance agriculture. Because Hydrogen is awkward to store and transport, most of it is currently used captive within large size centralized plants as a reactant for producing Hydrocarbon energy carriers, using the Carbon as a carrier for the Hydrogen moieties, to then be distributed over big enough areas for consumption of the such large scale plants’ volumes. With recently proven achievements of Hydrogen production from excess Wind & Solar Power by electrolysis, Hydrogen could become available in abundant quantities, to be distributed locally within the coverage area of the transmission grid such Wind & Solar installations are feeding into. In combination with Carbon as a reactant such abundant Hydrogen could also be synthesized into Hydrocarbon Energy Carriers and substitute fossil commodities. 展开更多
关键词 Atmospheric CARBON CARBON efficiency CARBON Metabolism CARBON RE-USE Chemical ENERGY Content Controlled Microbial Composting ENERGY Carriers Fossil Substitute Commodities INTERMEDIARIES Heating Value Hybrid Power Plant Hydrocarbon Hydrogen Organic Waste Valorization Photosynthesis Productivity REFINERIES
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Photosynthetic Water Use Efficiency of Heritage and Modern Potatoes under Limited and Unlimited Water Environments
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作者 Isaac R. Fandika Peter D. Kemp +1 位作者 James P. Millner Dave Horne 《Agricultural Sciences》 2014年第14期1501-1512,共12页
Photosynthetic capacity for heritage (Taewa) and modern potato cultivars were compared at different water and nitrogenregimes in the glasshouse and field. The glasshouse was 2*2*4 factorial design with two irrigation:... Photosynthetic capacity for heritage (Taewa) and modern potato cultivars were compared at different water and nitrogenregimes in the glasshouse and field. The glasshouse was 2*2*4 factorial design with two irrigation: 100% ET and 60% ET;two applied N: 50 kg N ha-1 and 200 kg N ha-1, two Taewa (Moe Moe, Tutaekuri) and two modern potatoes (Moonlight, Agria). The 2009/2010 field experiment was a split-plot, with irrigation and rain-fed regimes as the main treatments: four potatoes above were sub-treatments. The 2010/2011 field experiment was a split-split-plot, with three water regimes as the main treatments: three cultivars (Moe Moe, Tutaekuri, and Agria) were subplots;two N rates were sub-sub-treatments. Gaseous exchange was measured by CIRAS-2 at different days from emergence. Leaf water potential was measured using pressure chamber method. Taewa achieved high photosynthetic WUE in glasshouse and 2010/2011 experiment by maintaining high An, low gs and low Ci compared to modern cultivars (p The An, gs and T increased with irrigation and N increase while decreasing Ci (p < 0.01). Water stress significantly increased VPD resulting in low An and photosynthetic WUE in Moonlight in the glasshouse. The leaf water potential for Taewa was very tolerant while modern potatoes were weakened by water stress. The study indicated that Taewa can be scheduled at partial irrigation without more detrimental effects on photosynthetic capacity while modern potatoes need full irrigation to avoid detrimental effects on photosynthetic capacity. 展开更多
关键词 Taewa Photosynthesis STOMATAL Conductance (gs) Transpiration (T) Irrigation Internal Carbon concentration (Ci) Vapour Pressure Deficit (VPD) Leaf WATER Potential and PHOTOSYNTHETIC WATER Use efficiency (Photosynthetic WUE) SOLANUM TUBEROSUM SOLANUM andigena
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社会工作质性评估研究的回顾(1990-2003)对中国社会工作的启示 被引量:8
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作者 石丹理 韩晓燕 邓敏如 《社会》 北大核心 2005年第3期70-100,共31页
Objective: This paper reviewed and examined the quality of all the qualitative evaluation studies indexed by two key search terms of “qualitative” and “evaluation” in the Social Work Abstracts database from 1990 t... Objective: This paper reviewed and examined the quality of all the qualitative evaluation studies indexed by two key search terms of “qualitative” and “evaluation” in the Social Work Abstracts database from 1990 to 2003 against a number of criteria typically adopted in the field of qualitative research. The review led to a dissatisfactory finding of the low quality of many qualitative evaluation studies due to their insensitivity to the following issues: philosophical basis of the study, auditability (detailed documentation of the participants and data collecting procedure), biases (acknowledgement of biases and preoccupation, and steps to deal with them), credibility or trustworthiness (triangulation, peer checking and participant verification of the findings), consistency (reliability consciousness and audit trails), and critical interpretation of the data (alternative explanations, disconfirming evidence, and limitations of the study). It was recommended that researchers be cautious when utilizing findings from the published qualitative evaluation studies; that social workers be sensitive to the issue of quality when conducting qualitative evaluation studies; that researchers be critical when judging the qualitative evaluation studies in social work; that researchers develop a clear set of guidelines for qualitative studies; that social work training institutes design qualified qualitative research courses; that a database of social work in China be established; that researchers be engaged in more qualitative studies that demonstrate high quality; that myths in qualitative research be debunked; and that adequate training for social workers on qualitative evaluation studies be provided. 展开更多
关键词 database Abstracts that search when WORK design the and from AUDIT China This WORK MANY with MORE high for of be to all two The led set on
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他们不再是孩子了 关于“新失业群体”现状的社会学报告 被引量:28
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作者 吕鹏 《社会》 北大核心 2005年第4期119-142,共24页
The “New Unemployed” consists of young people with low education in the Chinese cities. They differ from the cohorts of their parents because they have no work experiences in any state- or collective-owned enterpris... The “New Unemployed” consists of young people with low education in the Chinese cities. They differ from the cohorts of their parents because they have no work experiences in any state- or collective-owned enterprise, and are subject to completely different policies designated by the government. Investigations of their daily living lead to the conclusion that the “New Unemployed” has gone through a “system withdrawal” process. They are now facing an environment of “system vacuum” that none of other unemployed groups has ever encountered before. The author emphasizes in the paper a strategic employment principle of “For Future Generations” so that focused attention and care can be provided and this toughest challenge in China can be dealt with. 展开更多
关键词 enterprise system Chinese because process people that before with other China and from have work GONE NONE ever care this The New has can of any For to so
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Thermodynamics and Irreversibility: From Some Paradoxes to the Efficiency of Effective Engines
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作者 Olivier Serret 《Journal of Modern Physics》 2014年第16期1575-1593,共19页
The traditional thermodynamic theory explains the reversible phenomena quite well, except that reversible phenomena are rare or even impossible in practice. Here the purpose is to propose an explanation valid for reve... The traditional thermodynamic theory explains the reversible phenomena quite well, except that reversible phenomena are rare or even impossible in practice. Here the purpose is to propose an explanation valid for reversible and also irreversible phenomena, irreversibility being common or realistic. It previously exposed points tricky to grasp, as the sign of the work exchange, the adiabatic expansion in vacuum (free expansion) or the transfer of heat between two bodies at the same temperature (isothermal transfer). After having slightly modified the concepts of heat transfer (each body produces heat according to its own temperature) and work (distinguishing external pressure from internal pressure), the previous points are more easily explained. At last, an engine efficiency in case of irreversible transfer is proposed. This paper is focused on the form of thermodynamics, on “explanations”;it does not question on “results” (except the irreversible free expansion of 1845...) which remain unchanged. 展开更多
关键词 Heat Transfer External and INTERNAL Pressure Work INTERNAL Energy Reversible and IRREVERSIBLE Joules Law and Joules Experiments ADIABATIC and Free Expansion Clapeyron Diagram Carnot Cycle Engine efficiency
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Practical strategies for increasing efficiency and effectiveness in critical care education 被引量:5
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作者 Maurice F Joyce Sheri Berg Edward A Bittner 《World Journal of Critical Care Medicine》 2017年第1期1-12,共12页
Technological advances and evolving demands inmedical care have led to challenges in ensuring adequate training for providers of critical care. Reliance on the traditional experience-based training model alone is insu... Technological advances and evolving demands inmedical care have led to challenges in ensuring adequate training for providers of critical care. Reliance on the traditional experience-based training model alone is insufficient for ensuring quality and safety in patient care. This article provides a brief overview of the existing educational practice within the critical care environment. Challenges to education within common daily activities of critical care practice are reviewed. Some practical evidence-based educational approaches are then described which can be incorporated into the daily practice of critical care without disrupting workflow or compromising the quality of patient care. It is hoped that such approaches for improving the efficiency and efficacy of critical care education will be integrated into training programs. 展开更多
关键词 Medical EDUCATION Critical care EDUCATIONAL efficiency EDUCATIONAL efficacy BEDSIDE teaching Flipped classroom Patient handover Multidisciplinary team practice In SITU simulation PROCEDURAL training
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Using KELEA (Kinetic Energy Limiting Electrostatic Attraction) to Improve the Efficiency of Fuel Combustion 被引量:1
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作者 W. John Martin 《Open Journal of Air Pollution》 2017年第3期103-116,共14页
There are many reports of devices and fuel additives being able to enhance the performance of automobiles and other forms of transportation that rely upon the combustion of gasoline or diesel fuels. The claims extend ... There are many reports of devices and fuel additives being able to enhance the performance of automobiles and other forms of transportation that rely upon the combustion of gasoline or diesel fuels. The claims extend from increased mileage and power to significant reductions in toxic exhaust emissions of carbon monoxide and unburnt hydrocarbons. Progress towards more widespread applications of means of improving fuel efficiency has been impeded by the lack of a coherent explanation of the mechanism of action. Fuel combustion allows for the conversion of much of the available chemical energy in volatile hydrocarbons to mechanical energy, which moves the pistons within an engine. It is proposed that the amount of chemical energy in hydrocarbons can be increased by the absorption of an environmental force termed KELEA (kinetic energy limiting electrostatic attraction). In addition to providing greater mechanical energy with relatively less heat output, the combustion of KELEA activated fuels proceeds further with less toxic emissions of carbon monoxide and unburnt hydrocarbons from incomplete combustion. KELEA activation of fuels should become standard practice in the transportation industry, with potential additional benefits in slowing the rate of global warming. 展开更多
关键词 KELEA Chemistry Transportation Hydrocarbons Combustion Fuel efficiency Air Pollution Exhaust Carbon MONOXIDE Gasoline Diesel Global WARMING PHOTOSYNTHESIS Hydrogen Electrical CHARGES
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Multi-objective ANN-driven genetic algorithm optimization of energy efficiency measures in an NZEB multi-family house building in Greece
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《建筑节能(中英文)》 2026年第2期62-62,共1页
The goal of the present work is to demonstrate the potential of Artificial Neural Network(ANN)-driven Genetic Algorithm(GA)methods for energy efficiency and economic performance optimization of energy efficiency measu... The goal of the present work is to demonstrate the potential of Artificial Neural Network(ANN)-driven Genetic Algorithm(GA)methods for energy efficiency and economic performance optimization of energy efficiency measures in a multi-family house building in Greece.The energy efficiency measures include different heating/cooling systems(such as low-temperature and high-temperature heat pumps,natural gas boilers,split units),building envelope components for floor,walls,roof and windows of variable heat transfer coefficients,the installation of solar thermal collectors and PVs.The calculations of the building loads and investment and operating and maintenance costs of the measures are based on the methodology defined in Directive 2010/31/EU,while economic assumptions are based on EN 15459-1 standard.Typically,multi-objective optimization of energy efficiency measures often requires the simulation of very large numbers of cases involving numerous possible combinations,resulting in intense computational load.The results of the study indicate that ANN-driven GA methods can be used as an alternative,valuable tool for reliably predicting the optimal measures which minimize primary energy consumption and life cycle cost of the building with greatly reduced computational requirements.Through GA methods,the computational time needed for obtaining the optimal solutions is reduced by 96.4%-96.8%. 展开更多
关键词 energy efficiency measures gas boilerssplit units building envelope components energy efficiency economic performance artificial neural network ann driven multi objective optimization economic performance optimization ANN driven GA methods
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From seed to whole plant:An innovative visual marker system to enhance selection efficiency in soybean genome editing
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作者 Tingwei Yan Xueyan Qian +5 位作者 Hong Pan Jiarui Han Qi Wang Chang Liu Dongquan Guo Xiangguo Liu 《Journal of Integrative Agriculture》 2026年第2期820-823,共4页
Emerging and powerful genome editing tools,particularly CRISPR/Cas9,are facilitating functional genomics research and accelerating crop improvement(Jiang et al.2021;Cao et al.2023;Chen C et al.2023;Liu et al.2023a).Ho... Emerging and powerful genome editing tools,particularly CRISPR/Cas9,are facilitating functional genomics research and accelerating crop improvement(Jiang et al.2021;Cao et al.2023;Chen C et al.2023;Liu et al.2023a).However,the detection and screening of transgenic lines remain major bottlenecks,being time-consuming,labor-intensive,and inefficient during transformation and subsequent mutation identification.A simple and efficient visual marker system plays a critical role in addressing these challenges.Recent studies demonstrated that the GmW1 and RUBY reporter systems were used to obtain visual transgenic soybean(Glycine max) plants(Chen L et al.2023;Chen et al.2024). 展开更多
关键词 accelerating crop improvement jiang mutation identificationa enhance selection efficiency SEED functional genomics research detection screening transgenic lines genome editing toolsparticularly innovative visual marker system
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Optimizing Nutrient Use Efficiency and Returns from Soybean Production under Smallholders in Three Agro-Ecologies of Malawi 被引量:1
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作者 Moses Munthali Patson Nalivata +5 位作者 Wilkson Makumba Emmanuel Mbewe Hastings Manase George Oduor Martin Macharia Kaizzi Kayuki 《Agricultural Sciences》 2017年第8期801-815,共15页
Field trials were conducted to determine the economically optimum fertilizer rates for soybean production and for optimizing net profits in Dedza, Lilongwe and Salima Districts of Malawi. The effects of PK fertilizer ... Field trials were conducted to determine the economically optimum fertilizer rates for soybean production and for optimizing net profits in Dedza, Lilongwe and Salima Districts of Malawi. The effects of PK fertilizer rates on rain use efficiency (RUE), harvest index, agronomic use efficiency of phosphorous (AEP) and potassium (AEK), and value cost ratio (VCR) were evaluated. The applied diagnostic PK fertilizer rates significantly improved soybean grain yields, harvest index, rainwater use efficiency, AEP, AEK and returns to fertilizer use expressed as value cost ratio (VCR). However, the results differed significantly 展开更多
关键词 SOYBEAN Net Returns Economically OPTIMUM Rates AGRONOMIC Use efficiency of Phosphorous and POTASSIUM NUTRIENT Combination Value Cost Ratio
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Layering Precision Land Leveling and Furrow Irrigated Raised Bed Planting: Productivity and Input Use Efficiency of Irrigated Bread Wheat in Indo-Gangetic Plains 被引量:5
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作者 M. L. Jat Raj Gupta +1 位作者 Y. S. Saharawat Raj Khosla 《American Journal of Plant Sciences》 2011年第4期578-588,共11页
Stagnating yield and declining input use efficiency in irrigated wheat of the Indo-Gangetic Plain (IGP) coupled with diminishing availability of water for agriculture is a major concern of food security in South Asia.... Stagnating yield and declining input use efficiency in irrigated wheat of the Indo-Gangetic Plain (IGP) coupled with diminishing availability of water for agriculture is a major concern of food security in South Asia. The objective of our study was to establish an understanding of how wheat yield and input use efficiency can be improved and how land leveling and crop establishment practices can be modified to be more efficient in water use through layering of precision-conservation crop management techniques. The “precision land leveling with raised bed” planting can be used to improve crop yield, water and nutrient use efficiency over the existing “traditional land leveling with flat” planting practices. We conducted a field experiment during 2002-2004 at Modipuram, India to quantify the benefits of alternate land leveling (precision land leveling) and crop establishment (furrow irrigated raised bed planting) techniques alone or in combination (layering precision-conservation) in terms of crop yield, water savings, and nutrient use efficiency of wheat production in IGP. The wheat yield was about 16.6% higher with nearly 50% less irrigation water with layering precision land leveling and raised bed planting compared to traditional practices (traditional land leveling with flat planting). The agronomic (AE) and uptake efficiency (UE) of N, P and K were significantly improved under precision land leveling with raised bed planting technique compared to other practices. 展开更多
关键词 Precision Land Leveling FURROW IRRIGATED Raised BED PLANTING Input Use efficiency IRRIGATED Bread Wheat Water PRODUCTIVITY Uptake efficiency Agronomic efficiency
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Economic Benefit Estimating of Polydimensional Efficiency Measurement Model Implementation
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作者 Andrey Aleksandrovich Shishkin Olga Andreevna Tyugai 《Open Journal of Applied Sciences》 2015年第3期108-114,共7页
This paper is a revised and expanded version of a paper entitled “The static and dynamic criteria of building an investment asset portfolio” presented at International Conference on Applied Economics (ICOAE, 2014), ... This paper is a revised and expanded version of a paper entitled “The static and dynamic criteria of building an investment asset portfolio” presented at International Conference on Applied Economics (ICOAE, 2014), Chania, 3-5 July 2014 and published at Procedia Economics and Finance, Volume 14, Pages 575-584 (2014) [1]. At the previous research, it showed the significance to go beyond the scope of selecting one or another metric of static efficiency. And the attention was paid to the dynamic efficiency criteria. The ICOAE 2015 research gives brief results of that work, which is only one of applied areas of polydimensional efficiency measurement model (PEMM). Research work on PEMM conceptual and methodical elaboration has been started in the author’s dissertation study [2] and continued in the practical activity and materialized in Innovative LLC (limited liability company) creating project. The research is concentrating on the real economic benefit of 3D PEMM (thee criterial PEMM version) implementation. In the first part of ICOAE 2015 empirical study, the dynamic component of 3D PEMM on the industrial level was tested. Next, the company economic profit changes and dynamic-market 3D PEMM components correlation was estimated. Finally, the economic benefit of 3D PEMM functional operationalization in the framework of management systems development was calculated. 展开更多
关键词 Investment Portfolio Shareholder VALUE Economic VALUE Added Dynamic Performance CRITERION CRITERION VALUE BASED MANAGEMENT efficiency Evaluation MODEL 3D MODEL VALUE BASED MANAGEMENT Corporate Governance Balanced Scorecard
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有杆泵携砂采油井筒配套技术 被引量:4
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作者 韩规划 《石油机械》 北大核心 2005年第5期42-45,85,共4页
针对采油井大范围出砂, 砂埋油层, 砂堵井筒, 频繁冲砂检泵致使有效采油时间缩短,油层污染加速, 常规采油工艺和“三抽”设备不能满足采油井在复杂地质条件下的生产需要等问题, 研发了有杆泵携砂采油井筒配套技术。该技术以提高系统采... 针对采油井大范围出砂, 砂埋油层, 砂堵井筒, 频繁冲砂检泵致使有效采油时间缩短,油层污染加速, 常规采油工艺和“三抽”设备不能满足采油井在复杂地质条件下的生产需要等问题, 研发了有杆泵携砂采油井筒配套技术。该技术以提高系统采油时效为目标, 在井筒内配置双柱塞抽油泵, 液力冲砂器和管柱沉砂器等机具, 通过与抽油机和抽油杆等杆管附件进行合理匹配,集冲搅砂和携砂为一体, 提高采油井有效生产时间, 达到增油和降低系统总体生产成本的目的。系统性能型式试验和工业生产试验说明, 该井筒配套技术通过在泵上实现存、携砂, 泵下冲搅砂等有效措施, 能使油井延长正常采油时间, 降低检泵作业次数, 减少油层污染并提高采油时效。 展开更多
关键词
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Efficiency of the Adaptive Cluster Sampling Designs in Estimation of Rare Populations
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作者 Charles Mwangi Ali Islam Luke Orawo 《Open Journal of Statistics》 2014年第5期412-418,共7页
Adaptive cluster sampling (ACS) has been a very important tool in estimation of population parameters of rare and clustered population. The fundamental idea behind this sampling plan is to decide on an initial sample ... Adaptive cluster sampling (ACS) has been a very important tool in estimation of population parameters of rare and clustered population. The fundamental idea behind this sampling plan is to decide on an initial sample from a defined population and to keep on sampling within the vicinity of the units that satisfy the condition that at least one characteristic of interest exists in a unit selected in the initial sample. Despite being an important tool for sampling rare and clustered population, adaptive cluster sampling design is unable to control the final sample size when no prior knowledge of the population is available. Thus adaptive cluster sampling with data-driven stopping rule (ACS’) was proposed to control the final sample size when prior knowledge of population structure is not available. This study examined the behavior of the HT, and HH estimator under the ACS design and ACS’ design using artificial population that is designed to have all the characteristics of a rare and clustered population. The efficiencies of the HT and HH estimator were used to determine the most efficient design in estimation of population mean in rare and clustered population. Results of both the simulated data and the real data show that the adaptive cluster sampling with stopping rule is more efficient for estimation of rare and clustered population than ordinary adaptive cluster sampling. 展开更多
关键词 ADAPTIVE CLUSTER Sampling with STOPPING Rule (ACS) Ordinary ADAPTIVE CLUSTER Sampling (ACS) Horvitz Thompson ESTIMATOR (HT) Hansen-Hurwitz ESTIMATOR (HH) Relative efficiency
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Highly stable carbon-based perovskite solar cell with a record efficiency of over 18% via hole transport engineering 被引量:7
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作者 Qian-Qian Chu Bin Ding +8 位作者 Jun Peng Heping Shen Xiaolei Li Yan Liu Cheng-Xin Li Chang-Jiu Li Guan-Jun Yang Thomas P. White Kylie R. Catchpole 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2019年第6期987-993,共7页
Carbon-based perovskite solar cells show great potential owing to their low-cost production and superior stability in air, compared to their counterparts using metal contacts. The photovoltaic performance of carbon-ba... Carbon-based perovskite solar cells show great potential owing to their low-cost production and superior stability in air, compared to their counterparts using metal contacts. The photovoltaic performance of carbon-based PSCs, however, has been progressing slowly in spite of an impressive efficiency when they were first reported. One of the major obstacles is that the hole transport materials developed for stateof-the-art Au-based PSCs are not suitable for carbon-based PSCs. Here, we develop a low-temperature,solution-processed Poly(3-hexylthiophene-2,5-diyl)(P3 HT)/graphene composite hole transport layer(HTL), that is compatible with paintable carbon-electrodes to produce state-of-the-art perovskite devices. Space-charge-limited-current measurements reveal that the as-prepared P3 HT/graphene composite exhibits outstanding charge mobility and thermal tolerance, with hole mobility increasing from8.3 × 10^-3 cm^2 V-1 s-1(as-deposited) to 1.2 × 10^-2 cm2 V^-1 s^-1(after annealing at 100°C)-two orders of magnitude larger than pure P3 HT. The improved charge transport and extraction provided by the composite HTL provides a significant efficiency improvement compared to cells with a pure P3 HT HTL. As a result, we report carbon-based solar cells with a record efficiency of 17.8%(certified by Newport);and the first perovskite cells to be certified under the stabilized testing protocol. The outstanding device stability is demonstrated by only 3% drop after storage in ambient conditions(humidity: ca. 50%) for 1680 h(nonencapsulated), and retention of ca. 89% of their original output under continuous 1-Sun illumination at room-temperature for 600 h(encapsulated) in a nitrogen environment. 展开更多
关键词 Planar carbon-based PEROVSKITE solar cells Hole transport ENGINEERING RECORDED efficiency EXCELLENT moisture and light stability
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关中西部畦灌优化灌水技术要素组合的初步研究 被引量:25
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作者 史学斌 马孝义 《灌溉排水学报》 CSCD 北大核心 2005年第2期39-43,80,共6页
在杨凌区砂壤土、中壤土的冬小麦和果树地,进行了畦田规格和灌水技术要素对水流推进和消退过程、灌水效率与灌水均匀度影响的田间试验,利用地面灌溉水流运动数学模型对畦灌条件下的最佳灌水技术要素组合进行了模拟和分析。结果表明,零... 在杨凌区砂壤土、中壤土的冬小麦和果树地,进行了畦田规格和灌水技术要素对水流推进和消退过程、灌水效率与灌水均匀度影响的田间试验,利用地面灌溉水流运动数学模型对畦灌条件下的最佳灌水技术要素组合进行了模拟和分析。结果表明,零惯量模型可以很好的模拟畦灌灌水过程中水流运动规律;畦田规格和灌水技术要素对灌水效率和灌水均匀度具有明显影响,对所研究的砂壤土冬小麦地在1‰、3‰田面坡度条件下,单宽流量以7L/(s·m)为宜,最大畦长应分别以40m、90m;对中壤土果树地1‰、3‰、5‰坡度条件下的畦长和单宽流量组合为分别以50m和6.0L/(s·m)、90m和6.0L/(s·m)、90m和5.0L/(s·m)左右为宜。同时为达到较高的灌水效率和灌水均匀度,畦田坡度不宜过大。 展开更多
关键词 西 退
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Working-memory training improves developmental dyslexia in Chinese children 被引量:8
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作者 Yan Luo Jing Wang +2 位作者 Hanrong Wu Dongmei Zhu Yu Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第5期452-460,共9页
Although plasticity in the neural system underlies working memory, and working memory can be improved by training, there is thus far no evidence that children with developmental dyslexia can benefit from working-memor... Although plasticity in the neural system underlies working memory, and working memory can be improved by training, there is thus far no evidence that children with developmental dyslexia can benefit from working-memory training. In the present study, thirty dyslexic children aged 8-11 years were recruited from an elementary school in Wuhan, China. They received working-memory training including training in visuospatial memory, verbal memory, and central executive tasks. The difficulty of the tasks was adjusted based on the performance of each subject, and the training sessions lasted 40 minutes per day, for 5 weeks. The results showed that working-memory training significantly enhanced performance on the nontrained working memory tasks such as the visuospatial, the verbal domains, and central executive tasks in children with developmental dyslexia. More importantly, the visual rhyming task and reading fluency task were also significantly improved by training. Progress on working memory measures was related to changes in reading skills. These experimental findings indicate that working memory is a pivotal factor in reading development among children with developmental dyslexia, and interventions to improve working memory may help dyslexic children to become more proficient in reading. 展开更多
关键词 neural regeneration NEUROREHABILITATION developmental dyslexia working memory training visuospatial memory verbal memory central executive task visual rhyming task reading fluency task Chinese children brain function grants-supported paper photographs-containing paper neuroregeneration
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Cereal-forage crop rotations and irrigation treatment effect on water use efficiency and crops sustainability in Mediterranean environment
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作者 Pasquale Martiniello 《Agricultural Sciences》 2012年第1期44-57,共14页
Agricultural systems based on crop rotations favour sustainability of cultivation and productivity of the crops. Wheat-forage crops rotations (annual winter binary mixture and perennial alfalfa meadow) combined with i... Agricultural systems based on crop rotations favour sustainability of cultivation and productivity of the crops. Wheat-forage crops rotations (annual winter binary mixture and perennial alfalfa meadow) combined with irrigation are the agronomical techniques able to better exploit the weather resources in Mediterranean environments. The experiment aimed to study the effect of 18 years of combined effect of irrigation and continuous durum wheat and wheat-forage rotations on productivities of crops and organic matter of topsoil. The experiments were established through 1991-2008 under rainfed and irrigated treatments and emphasized on the effect of irrigation and continuous wheat and wheat-forage crop rotations on water use efficiency and sustainability of organic matter. The effect of irrigation increased 49.1% and 66.9% the dry matter of mixture and meadow, respectively. Continuous wheat rotation reduced seed yield, stability of production, crude protein characteristics of kernel and soil organic matter. The yearly gain in wheat after forage crops was 0.04 t (ha·yr)-1 under rainfed and 0.07 t (ha·yr)-1 under irrigation treatments. The crude protein and soil organic matter of wheat rotations, compared to those of continuous wheat under rainfed and irrigated was increase in term of point percentage by 0.8 and 0.5 in crude protein and 5.1 and 4.4 in organic matter, respectively. The rotations of mixture and meadow under both irrigated treatments increased the point of percentage of organic matter over continuous wheat (9.3.and 8.5 in mixture and 12.5 and 9.5 meadow under rainfed and irrigation, respectively). Irrigation reduce the impact of weather on crop growing reducing water use efficiency (mean over rotations) for dry mater production (15.5 in meadow and 17.5 in mixture [L water (kg·dry·matter)-1 ]) and wheat seed yield. The effect of agronomic advantages achieved by forage crops in topsoil expire its effect after three years of continuous wheat rotation. 展开更多
关键词 Alfalfa Binary Mixture DURUM WHEAT IRRIGATION Mediterranean Environment Soil Organic Matter Water Use efficiency Wheat-Forage ROTATIONS
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Difference of Nitrogen Uptake and Use Efficiency in Conventional Indica Rice Cultivars with Different Nitrogen Use Efficiency for Grain Output 被引量:3
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作者 周娟 李进前 +4 位作者 张彪 张传胜 张岳芳 王余龙 董桂春 《Agricultural Science & Technology》 CAS 2008年第6期68-73,141,共7页
[Objective] The study aimed to confirm difference of nitrogen uptake and used efficiency with different nitrogen use efficiency for grain output (NUEg) types of indica rice.[Method] 88 and 122 conventional indica rice... [Objective] The study aimed to confirm difference of nitrogen uptake and used efficiency with different nitrogen use efficiency for grain output (NUEg) types of indica rice.[Method] 88 and 122 conventional indica rice cultivars were solution-cultured in 2001 and 2002, respectively. Dry matter weight (including root system, culm and sheath, leaves, panicle), nitrogen content of different organs, yield and its components were measured. The tested rice cultivars were classified into 6 types (i.e. A, B, C, D, E and F, A was the lowest, and F was the highest) based on their NUEg level by the MinSSw method.[Result](1)Difference of NUEg of the cultivars used in this study were very large; (2) No significant difference of N content at heading stage was observed among different NUEg types of indica rice. In the cultivars with higher NUEg, however, N content in leaf, stem-sheath and entire rice plant were lower at mature stage. (3)Cultivars with higher NUEg were characterized with lower N uptake before heading and at mature stage; (4) Cultivars with higher NUEg were characterized with higher N use efficiency in biomass production and harvest index. [Conclusion] The cultivars with higher NUEg showed lower N uptake and N content, while nitrogen use efficiency was higher. 展开更多
关键词 Conventional INDICA rice CULTIVARS NITROGEN content for grain output NITROGEN UPTAKE NITROGEN use efficiency
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快速城市化地区土地利用效益评价——以南京市江宁区为例 被引量:121
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作者 彭建 蒋依依 +3 位作者 李正国 张小飞 李卫锋 岳隽 《长江流域资源与环境》 CAS CSSCI CSCD 北大核心 2005年第3期304-309,共6页
作为衡量土地利用可持续性的重要标度,土地利用效益评价是近年来国内外城市土地研究的热点之一。从社会、经济、生态与环境等四方面建立了快速城市化地区土地利用效益评价的指标体系,利用层次分析法确定各指标权重,构建各效益子系统的... 作为衡量土地利用可持续性的重要标度,土地利用效益评价是近年来国内外城市土地研究的热点之一。从社会、经济、生态与环境等四方面建立了快速城市化地区土地利用效益评价的指标体系,利用层次分析法确定各指标权重,构建各效益子系统的协调度评价模型。并对南京市江宁区2003年的土地利用效益进行了综合评价,结果表明,全区总体土地利用效益适中且基本协调,但各乡镇间土地利用效益及其协调性的区域差异显著。依据各乡镇土地利用总效益及其协调度的聚类分级,可将全区划分为土地利用高效协调区、高效基本协调区、高效不协调区、中效协调区、中效基本协调区、中效不协调区与低效基本协调区等七大土地利用效益类型区,并分析了其区域差异的空间特征。 展开更多
关键词 2003
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