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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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GaInP/GaInAs/GaInNAs/Ge Four-Junction Solar Cell Grown by Metal Organic Chemical Vapor Deposition with High Efficiency
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作者 张杨 王青 +5 位作者 张小宾 刘振奇 陈丙振 黄珊珊 彭娜 王智勇 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第10期167-171,共5页
We directly grow a lattice matched GalnP/GalnAs/GalnNAs/Ge (1.88 eVil .42 eVil .05 eV/0.67eV) four-junction (4J) solar cell on a Ge substrate by the metal organic chemical vapor deposition technology. To solve the... We directly grow a lattice matched GalnP/GalnAs/GalnNAs/Ge (1.88 eVil .42 eVil .05 eV/0.67eV) four-junction (4J) solar cell on a Ge substrate by the metal organic chemical vapor deposition technology. To solve the current limit of the GalnNAs sub cell, we design three kinds of anti-reflection coatings and adjust the base region thickness of the GalnNAs sub cell. Developed by a series of experiments, the external quantum efficiency of the GalnNAs sub cell exceeds 80%, and its current density reaches 11.24 mA/cm2. Therefore the current limit of the 4J solar cell is significantly improved. Moreover, we discuss the difference of test results between 4J and GalnP/GalnAs/Ge solar cells under the 1 sun AMO spectrum. 展开更多
关键词 by on it of GaInP/GaInAs/GaInNAs/Ge Four-Junction Solar Cell Grown by Metal Organic Chemical Vapor Deposition with high efficiency is THAN Ge GaAs with cell that
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HOW TO ENLARGE YOUR VOCABULARY WITH HIGH EFFICIENCY
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作者 Chen Chuan-li 《曲靖师范学院学报》 1998年第Z1期64-67,共4页
This article states the importance and hardship of memorising English words, propose some effective specific examples to solve them and sum up some memory techniques.
关键词 efficiency VOCABULARY association ANTONYM SYNONYM HOMOPHONE word formation classification ETYMOLOGY simple drawing.
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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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The Implementation of a High Efficiency Full-Bridge Converter
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作者 Joy Iong-Zong Chen 《Engineering(科研)》 2011年第4期331-339,共9页
A high efficiency full-bridge converter is investigated and implemented in this paper. The measured data result from the other converter implemented by IC UCC3895 is to compare with that of the previous converter. Thi... A high efficiency full-bridge converter is investigated and implemented in this paper. The measured data result from the other converter implemented by IC UCC3895 is to compare with that of the previous converter. This full-bridge converter proposed and implemented converter can obtain about 96% power efficiency in conversion procedure when compared with that of 90%, which were ever published by the conventional techniques. Apart from, the L-C resonance circuits were developed and embedded into the popular PWM (pulse width modulation) power converter, which is referred as the soft-switching, so as to down sizing the volume of the IC which can totally reduces the power losses caused in the duration of a semi-con- ductor switching. 展开更多
关键词 high efficiency FULL-BRIDGE CONVERTER SWITCHING LOSSES SYNCHRONIZATION FILTER
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Hierarchical microstructures with high spatial frequency laser induced periodic surface structures possessing different orientations created by femtosecond laser ablation of silicon in liquids 被引量:17
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作者 Dongshi Zhang Koji Sugioka 《Opto-Electronic Advances》 2019年第3期1-18,共18页
High spatial frequency laser induced periodic surface structures(HSFLs)on silicon substrates are often developed on flat surfaces at low fluences near ablation threshold of 0.1 J/cm2,seldom on microstructures or micro... High spatial frequency laser induced periodic surface structures(HSFLs)on silicon substrates are often developed on flat surfaces at low fluences near ablation threshold of 0.1 J/cm2,seldom on microstructures or microgrooves at relatively higher fluences above 1 J/cm^2.This work aims to enrich the variety of HSFLs-containing hierarchical microstructures,by femtosecond laser(pulse duration:457 fs,wavelength:1045 nm,and repetition rate:100 kHz)in liquids(water and acetone)at laser fluence of 1.7 J/cm^2.The period of Si-HSFLs in the range of 110–200 nm is independent of the scanning speeds(0.1,0.5,1 and 2 mm/s),line intervals(5,15 and 20μm)of scanning lines and scanning directions(perpendicular or parallel to light polarization direction).It is interestingly found that besides normal HSFLs whose orientations are perpendicular to the direction of light polarization,both clockwise or anticlockwise randomly tilted HSFLs with a maximal deviation angle of 50°as compared to those of normal HSFLSs are found on the microstructures with height gradients.Raman spectra and SEM characterization jointly clarify that surface melting and nanocapillary waves play important roles in the formation of Si-HSFLs.The fact that no HSFLs are produced by laser ablation in air indicates that moderate melting facilitated with ultrafast liquid cooling is beneficial for the formation of HSFLs by LALs.On the basis of our findings and previous reports,a synergistic formation mechanism for HSFLs at high fluence was proposed and discussed,including thermal melting with the concomitance of ultrafast cooling in liquids,transformation of the molten layers into ripples and nanotips by surface plasmon polaritons(SPP)and second-harmonic generation(SHG),and modulation of Si-HSFLs direction by both nanocapillary waves and the localized electric field coming from the excited large Si particles. 展开更多
关键词 high spatial frequency LASER induced periodic SURFACE structures SILICON LASER ablation in liquids HIERARCHICAL MICROSTRUCTURES femtosecond LASER high fluence formation mechanism SURFACE melting nanocapillary wave SURFACE plasmon polaritons second-harmonic generation
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A High Efficiency Doherty Power Amplifier for TV Band Applications
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作者 Mohamad Y. Abou-Shahine Youssef Nasser Karim Y. Kabalan 《Journal of Electromagnetic Analysis and Applications》 2015年第12期291-301,共11页
This paper presents a high efficiency Doherty power amplifier suitable for TV band applications. A class AB power amplifier is firstly implemented using a commercial GaN HEMT from Cree Incorporation, achieving a high ... This paper presents a high efficiency Doherty power amplifier suitable for TV band applications. A class AB power amplifier is firstly implemented using a commercial GaN HEMT from Cree Incorporation, achieving a high power-added-efficiency of 77.78% and a 40.593 dBm output power with an associated gain of 21.65 dB. The Doherty amplifier has then been designed following the previous class AB scheme for the main amplifier and a class C scheme for the peak one. This amplifier attained a high power-added-efficiency of 81.94%, a 42.77 dBm output power, an associated gain of 21.32 dB, and an operating frequency bandwidth between 550 and 1000 MHz (58.06% fractional bandwidth) which made it suitable for TV band applications. 展开更多
关键词 POWER AMPLIFIER Class AB DOHERTY POWER AMPLIFIER efficiency TV BAND
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SINAMICS—the high efficiency drive technology for rolling mills
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作者 Prabhuraj BHOOPLAPUR Harald WIECHMANN 《Baosteel Technical Research》 CAS 2010年第S1期101-,共1页
In the Metals Industry,interruption-free processes to produce high-quality end products are a prerequisite. The main drives together with the mill stands play a key role in the success of rolling mills.The crucial dem... In the Metals Industry,interruption-free processes to produce high-quality end products are a prerequisite. The main drives together with the mill stands play a key role in the success of rolling mills.The crucial demands placed on the drive system are:high-dynamic performance of drive and its control system,ability to handle the process related overloads,smooth running,high availability,high efficiency,easy serviceability and ability to integrate seamlessly with the automation systems.With numerous reference installations and many years of experience Siemens VAI has the wider expertise and the portfolio to provide the right drive for every application. This paper examines the latest innovation,SINAMICS drive technology,for both new drive applications as well as for modernizing the existing drives in rolling mill applications like hot strips mills,plate mills,cold rolling mills,and long rolling mills. 展开更多
关键词 rolling mill drives synchronous motors induction motors voltage source converter CYCLOCONVERTER multi-level voltage source converters energy efficient drives SINAMICS
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DEVELOPMENT AND EXPERIMENT OF NEW AlTiN COATED DRILLS FOR HIGH EFFICIENCY DRY DRILLING OF 40Cr 被引量:4
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作者 沈中 刘钢 陈明 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第2期106-111,共6页
Two new AlTiN coated cemented carbide drills with Al content of 40% and 55% in weight are developed for high efficiency dry drilling of 40Cr. By studying tool durability, machined hole quality, tool wear mechanism, ch... Two new AlTiN coated cemented carbide drills with Al content of 40% and 55% in weight are developed for high efficiency dry drilling of 40Cr. By studying tool durability, machined hole quality, tool wear mechanism, chip deformation, and lubrication, the dry drilling performance of the two kinds of coated drills is analyzed. Experimental results show that the AlTiN coated drills are suitable for high efficiency dry drilling and can obtain higher quality of machined holes. The tool durability of the drill with 55% Al content is 1. 3 times of that of the drill with 40% Al content at the cutting speed of 90 m/min. The wear mechanism of two AlTiN coatings are studied in experiments. During dry drilling process, oxidative wear appears in both two kinds of drills. The oxide film is formed on the top of the coated drill containing Al content of 55%. And the oxide film helps to increase its high temperature resistance and decrease the coating flaking, thus the drill is failed because of coating subsidence. The drill with less Al content is failed due to peeling and breakage. The lubricated condition in dry drilling is improved by the high Al content coating. It helps to reduce the cutting deformation and benefits to improve the quality of machined holes. The AlTiN coating with higher Al content shows longer tool life and higher quality of machined holes in high efficiency dry drilling. Its tool life increases by 30% compared with that of the coating with less Al content. 展开更多
关键词 high efficiency machining COATING AlTiN dry drilling 40Cr
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Electrodeposition of Gold to Conformally Fill High-Aspect-Ratio Nanometric Silicon Grating Trenches: A Comparison of Pulsed and Direct Current Protocols 被引量:2
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作者 Sami Znati Nicholas Chedid +3 位作者 Houxun Miao Lei Chen Eric E. Bennett Han Wen 《Journal of Surface Engineered Materials and Advanced Technology》 2015年第4期207-213,共7页
Filling high-aspect-ratio trenches with gold is a frequent requirement in the fabrication of X-ray optics as well as micro-electronic components and other fabrication processes. Conformal electrodeposition of gold in ... Filling high-aspect-ratio trenches with gold is a frequent requirement in the fabrication of X-ray optics as well as micro-electronic components and other fabrication processes. Conformal electrodeposition of gold in sub-micron-width silicon trenches with an aspect ratio greater than 35 over a grating area of several square centimeters is challenging and has not been described in the literature previously. A comparison of pulsed plating and constant current plating led to a gold electroplating protocol that reliably filled trenches for such structures. 展开更多
关键词 PULSED ELECTROPLATING Gold ELECTROPLATING high Aspect Ratio TRENCHES Gold Electrodepostion Di-rect Current Electrodeposition PULSED vs. Direct Current ELECTROPLATING Atomic LAYER Deposition Platinum Seed LAYER Silicon TRENCH Gratings TRENCH FILLING Grating FILLING ALD Adhesive LAYER
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Pt-Al<sub>2</sub>OM<sub>3</sub>Composite Material Designed for Cyclic Production of Optical Glasses under High Temperature Conditions
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作者 Aleksandr Bochegov Aleksandr Ermakov Irina Vandysheva 《Journal of Materials Science and Chemical Engineering》 2014年第3期30-36,共7页
The article considers one of the possible approaches to the solution of an urgent issue of metal consumption reduction, increase of operating life and maximum operating temperature as well as reduction of irrecoverabl... The article considers one of the possible approaches to the solution of an urgent issue of metal consumption reduction, increase of operating life and maximum operating temperature as well as reduction of irrecoverable losses of platinum products and alloys when operating under high temperature conditions, particularly for glassblowing and single crystal growing crucibles. A two-layered composite material based on platinum-group metals and corundum plasma ceramics is thoroughly investigated. A successful experience of crucibles exploitation, designed for production of high temperature optical glasses from the composite and results of the research on composite material specimens are described. 展开更多
关键词 Sandwich-Structured Composite Material Plasmaceramics Platinum-Group Metals Reduction of Metal Consumption Crucibles for Glassblowing and Single Crystal Growing high TEMPERATURE Creep high TEMPERATURE Strength and Heat Resistance Irrecoverable Losses
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High mobility group box 1 in the central nervous system:regeneration hidden beneath inflammation
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作者 Hanki Kim Bum Jun Kim +4 位作者 Seungyon Koh Hyo Jin Cho Xuelian Jin Byung Gon Kim Jun Young Choi 《Neural Regeneration Research》 SCIE CAS 2025年第1期107-115,共9页
High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and neuroscience.High-mobility group box 1 in the ex... High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and neuroscience.High-mobility group box 1 in the extracellular space functions as a pro-inflammatory damage-associated molecular pattern,which has been proven to play an important role in a wide variety of central nervous system disorders such as ischemic stroke,Alzheimer’s disease,frontotemporal dementia,Parkinson’s disease,multiple sclerosis,epilepsy,and traumatic brain injury.Several drugs that inhibit high-mobility group box 1 as a damage-associated molecular pattern,such as glycyrrhizin,ethyl pyruvate,and neutralizing anti-high-mobility group box 1 antibodies,are commonly used to target high-mobility group box 1 activity in central nervous system disorders.Although it is commonly known for its detrimental inflammatory effect,high-mobility group box 1 has also been shown to have beneficial pro-regenerative roles in central nervous system disorders.In this narrative review,we provide a brief summary of the history of high-mobility group box 1 research and its characterization as a damage-associated molecular pattern,its downstream receptors,and intracellular signaling pathways,how high-mobility group box 1 exerts the repair-favoring roles in general and in the central nervous system,and clues on how to differentiate the pro-regenerative from the pro-inflammatory role.Research targeting high-mobility group box 1 in the central nervous system may benefit from differentiating between the two functions rather than overall suppression of high-mobility group box 1. 展开更多
关键词 central nervous system damage-associated molecular pattern ethyl pyruvate glycyrhizzin high mobility group box 1 INFLAMMATION neural stem cells NEURODEVELOPMENT oligodendrocyte progenitor cells redox status REGENERATION
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Breeding of National Authorized New Wheat Variety Shannong 116 and Supporting Cultivation Technical Measures for High Yield, High Quality and High Efficiency
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作者 Yanxun WANG Jichun TIAN +1 位作者 Ming YANG Li PENG 《Plant Diseases and Pests》 CAS 2023年第3期19-21,26,共4页
Shannong 116 is a strong gluten,high yield and multi-resistance wheat variety bred by Shandong Agricultural University,which was approved by the State in 2021 and by Shandong Province in 2022.Shannong 116 combines the... Shannong 116 is a strong gluten,high yield and multi-resistance wheat variety bred by Shandong Agricultural University,which was approved by the State in 2021 and by Shandong Province in 2022.Shannong 116 combines the excellent characteristics of the female parent(strong gluten,disease resistance and early maturity)and the male parent(high yield,water saving and lodging resistance),with a plant height of 76.9 cm,compact plant type,orderly spike layer and good maturity performance,which is suitable for large-scale promotion and market order planting in Huanghuai wheat area.In this paper,the characteristics of Shannong 116 are analyzed,and cultivation technical measures for high yield,high quality and high efficiency are put forward,in order to provide a technical support for the popularization and application of the variety. 展开更多
关键词 National authorized wheat Shannong 116 BREEDING high yield high quality high efficiency Cultivation measures
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Distributed High Efficiency Renewable Power Systems With Modules in Series Connection 被引量:1
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作者 WU Hongfei SUN Kai XING Yan 《中国电机工程学报》 EI CSCD 北大核心 2012年第33期I0001-I0022,共22页
关键词
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Research and Development of New High-quality Short-season Cotton Varieties and the Industrial Application of High Efficiency Technologies in Shandong Province——Based on the Innovation of Building a Green and Efficient Farming System
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作者 Guifeng WANG Guofang HAO +4 位作者 Shaohong ZHANG Yongming LI Han GAO Kaichun LI Yong FANG 《Agricultural Biotechnology》 CAS 2021年第5期49-55,共7页
Through the analysis of the impact of changes in the cotton planting industry on cotton production structure and benefit in Shandong under the national cotton production pattern in past ten years,based on the guarante... Through the analysis of the impact of changes in the cotton planting industry on cotton production structure and benefit in Shandong under the national cotton production pattern in past ten years,based on the guarantee of food security and the overall ecological regional layout of Shandong s agricultural characteristic and advantageous industries,we proposed that through the development of high-quality short-season cotton and the industrial application of high-efficiency technologies,a green and high-efficiency farming system should be established to comprehensively reduce cotton planting costs,improve comparative benefits,and realize green and efficient optimization technologies that unify the stable production of cotton and high-quality cotton supply and the industrial path supported by the new industrial model.It is aimed to speed up the upgrading and transformation of the existing traditional cotton cropping system,reconstruct a ternary structure of grains,economic crops and fodder in the ecological suitable cotton areas and sub-suitable cotton areas in Shandong,and maintain a series of new green and ecological cotton rotation industrial models including the“double security”of the grain and cotton industries,the ecological“double superiority”of "cotton and fodder",and the high-efficiency"double increase"of cotton and garlic,providing a certain foundation for the research on technological integration innovation and industrial structure optimization of the green,efficient and high-quality development and transformation of the cotton industry in Shandong during the"14 th Five-Year Plan"period. 展开更多
关键词 Shandong Province Green high efficiency and high quality Cultivation system high-quality specially-purposed Short-season cotton INDUSTRIALIZATION
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Research on High-Efficiency Cyclone Separators and Their Optimum Design 被引量:1
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作者 Shi Mingxian, Jin Youhai, Wu Xiaolin, Chen Jianyi, Liu Junren (United Research Institute of Applied Chemistry and Chemical Engineering, University of Petroleum, Beijing 100083) 《石油学报(石油加工)》 EI CAS CSCD 北大核心 1997年第S1期19-27,共9页
ResearchonHighEficiencyCycloneSeparatorsandTheirOptimumDesignShiMingxian,JinYouhai,WuXiaolin,ChenJianyi,Liu... ResearchonHighEficiencyCycloneSeparatorsandTheirOptimumDesignShiMingxian,JinYouhai,WuXiaolin,ChenJianyi,LiuJunren(UnitedRese... 展开更多
关键词 CYCLONE SEPARATOR flow field distribution of particle concentration OPTIMUM DESIGN efficiency pressure DROP multicyclone SEPARATOR
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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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Evaluation of Vaporized Hydrogen Peroxide Fumigation as a Method for the Bio-decontamination of the High Efficiency Particulate Air Filter Unit 被引量:8
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作者 JIA Hai Quan LI Yan Ju +6 位作者 SUN Bei ZHAO Si Qing YI Ying ZHAO Ming ZHANG Zong Xing PAN Xin QI Jian Cheng 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第2期110-117,共8页
Objective To evaluate the performance of vaporized hydrogen peroxide (VHP) for the bio-decontamination of the high efficiency particulate air (HEPA) filter unit. Methods Self-made or commercially available bioindi... Objective To evaluate the performance of vaporized hydrogen peroxide (VHP) for the bio-decontamination of the high efficiency particulate air (HEPA) filter unit. Methods Self-made or commercially available bioindicators were placed at designated locations in the HEPA filter unit under VHP fumigation. The spores on coupons were then extracted by 0.5 h submergence in eluent followed by 200- time violent knocks. Results Due to the presence of HEPA filter in the box, spore recovery from coupons placed at the bottom of the filter downstream was significantly higher than that from coupons placed at the other locations. The gap of decontamination efficiency between the top and the bottom of the filter downstream became narrower with the exposure time extended. The decontamination efficiency of the bottom of the filter downstream only improved gently with the injection rate of H202 increased and the decontamination efficiency decreased instead when the injection rate exceeded 2.5 g/min. The commercially available bioindicators were competent to indicate the disinfection efficiency of VHP for the HEPA filter unit. Conclusion The HEPA filter unit is more difficult than common enclosure to decontaminate using VHP fumigation. Complete decontamination can be achieved by extending fumigation time. VHP fumigation can be applied for in-situ biodecontamination of the HEPA filter unit as an alternative method to formaldehyde fumigation. 展开更多
关键词 Vaporized hydrogen peroxide FUMIGATION Bio-decontamination high efficiency particulateair filter unit Spore killing
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Practical strategies for increasing efficiency and effectiveness in critical care education 被引量:4
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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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太行山南段符山高镁闪长岩的成因——拆沉陆壳物质熔融的熔体与地幔橄榄岩反应的结果 被引量:40
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作者 许文良 杨德彬 +1 位作者 裴福萍 于洋 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第8期1947-1961,共15页
本文对太行山南段符山高镁闪长岩进行了年代学与地球化学研究,结合其中地幔橄榄岩包体的研究,对符山高镁闪长岩的成因和中生代岩石圈地幔的性质进行了探讨。研究表明,符山闪长岩体是由一套含橄榄石角闪闪长岩-角闪闪长岩-闪长岩构成。... 本文对太行山南段符山高镁闪长岩进行了年代学与地球化学研究,结合其中地幔橄榄岩包体的研究,对符山高镁闪长岩的成因和中生代岩石圈地幔的性质进行了探讨。研究表明,符山闪长岩体是由一套含橄榄石角闪闪长岩-角闪闪长岩-闪长岩构成。含橄榄岩包体的寄主岩——角闪闪长岩中的锆石可划分为两种:一是代表寄主岩浆结晶的锆石:内部结构均匀、呈条带状吸收、自形-半自形晶形,具有较高的Th/U比值(1.10~4.08),其^(206)Pb/^(238)U年龄介于123~128Ma之间,12个点的加权平均值为125±1Ma,这表明岩体的形成时代为早白垩世;二是捕获或继承锆石:具有核边结构、吸收程度不均匀、呈浑圆状和自形-半自形两种,它们的Th/U比值介于0.32~2.03之间,构成了3组^(207)Pb/^(206)Pb加权平均年龄:2503±11Ma、2181±26Ma和1778±36Ma。该类岩石的SiO_2和MgO含量分别介于56.69%~59.21%和3.60%~6.33%之间;且以高Mg~#(0.51~0.64)、富Na(Na_2O/K_2O大于1)、高Cr(93.1×10^(-6)~420×10^(-6))、Ni(35.1×10^(-6)~137×10^(-6))为特征。该类岩石强烈富集轻稀土元素和大离子亲石元素、明显亏损高场强元素,(^(87)Sr/^(86)Sr)_i、ε_(Nd)(t)值和(^(206)Pb/^(204)Pb)_i分别变化于0.70581~0.70641、-8.30~-16.56和17.052~17.512之间。综合上述特征,同时结合地慢橄榄岩包体的特征和古元古代捕获锆石的大量存在,认为符山高镁闪长岩的原始岩浆起源于拆沉陆壳物质的部分熔融,其后经历了与地幔橄榄岩的反应过程。 展开更多
关键词 North China Craton central southern continental crust partial melting peridotite XENOLITHS high field strength rare earth elements crystallization time lithospheric mantle
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