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贯流式斜向空间导叶全三维密合设计 被引量:1
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作者 李凤超 樊红刚 +1 位作者 王正伟 陈乃祥 《清华大学学报(自然科学版)》 EI CAS CSCD 北大核心 2010年第2期266-269,共4页
为实现贯流式机组斜向空间导叶的密合设计,提出了一种基于最优化技术的设计方法。利用全三维反问题模型设计导叶叶型,保证它具有良好的绕流性能,并为转轮提供必需的环量。以出口边和进口边附近叶片表面上的准正交网格线构成密合基线为目... 为实现贯流式机组斜向空间导叶的密合设计,提出了一种基于最优化技术的设计方法。利用全三维反问题模型设计导叶叶型,保证它具有良好的绕流性能,并为转轮提供必需的环量。以出口边和进口边附近叶片表面上的准正交网格线构成密合基线为目标,采用单纯形加速法控制速度矩参数的变化,使得叶型逐步满足密合要求。导叶和桨叶进行联合数值模拟,结果表明,设计的导叶绕流水力损失小,并且设计计算具有足够的精度。 展开更多
关键词 贯流式水轮机 锥形导叶 密合设计 全三维 单纯形加速法
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面具密合框设计 被引量:8
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作者 李小银 《中国劳动防护用品》 1997年第4期11-21,共11页
一、概述 防毒面具密合框位于罩体内侧的周边,是面罩与佩带者面部贴合的部分或部件,由橡胶材料制成。在传统结构的面具中,密合框与罩体主体是一个整体部件,如常见的我国59型、64型及87型防毒面具等;在新结构的全脸式面具如意大利SGE100... 一、概述 防毒面具密合框位于罩体内侧的周边,是面罩与佩带者面部贴合的部分或部件,由橡胶材料制成。在传统结构的面具中,密合框与罩体主体是一个整体部件,如常见的我国59型、64型及87型防毒面具等;在新结构的全脸式面具如意大利SGE1000型面具和德国Draser futura面罩中,这两部分为两个独立的部件,罩体主体用聚碳酸酯。 展开更多
关键词 防毒面具 密合设计 防护服
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Ultra-fast Maize (Zea mays L.) Hybrid Growth Response to Plant Population Density
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作者 Gobeze Loha Yada Gert Michael Ceronio Leon Daniel Van Rensburg 《Journal of Agricultural Science and Technology(B)》 2013年第5期334-343,共10页
Current arable land and increasing food demand necessitates the practice of double and multiple cropping systems with inclusion of ultra-fast maize hybrids, which are characterized by smaller size, fewer leaves per pl... Current arable land and increasing food demand necessitates the practice of double and multiple cropping systems with inclusion of ultra-fast maize hybrids, which are characterized by smaller size, fewer leaves per plant, lower leaf area and fewer self-shading problems, under irrigation. In this context, a field experiment was conducted for two successive cropping seasons 2008/2009 to 2009/2010 at Kenilworth Experimental Station to evaluate the effect of row spacings and plant density on growth. Three row spacing (0.225, 0.45 and 0.90 m) and five plant densities (5, 7.5, 10, 12.5 and 15 plants m^-2) were used. Treatments were combined in a factorial combination and laid out in a completely randomized design with replications consisting of five single plants randomly selected from each treatment for destructive sampling. Growth factors reacted differently to row spacing by plant density. At crop establishment, growth indicators were not significantly affected by either main effects or a combination thereof. However, at the end of the vegetative phase, almost all growth indicators reached a maximum and were significantly affected by treatment interactions. Growth analysis showed that there was an interaction effect of row spacing by plant density on plant height, dry matter (DM) accumulation, leaf area index (LAI), crop growth rate (CGR) and net assimilation rate (NAR) of maize. Therefore, the current investigation demonstrated that a row spacing of 0.45 m or 0.90 m with a plant density of 10 plants m^-2 was optimum for the selected ultra-fast maize hybrid under irrigation. 展开更多
关键词 MAIZE IRRIGATION plant population YIELD row spacing
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Design Details of Low-Energy and Passive Houses Using Composites from Waste Raw Materials
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作者 Libor Matejka Jan Pencik 《Journal of Civil Engineering and Architecture》 2011年第5期440-453,共14页
The article deals with potential use of waste materials in construction industry, specifically use of high density polyethylene (HDPE). The article is focused in particular on recycled polyethylene application in pr... The article deals with potential use of waste materials in construction industry, specifically use of high density polyethylene (HDPE). The article is focused in particular on recycled polyethylene application in products designed for construction industry, especially for passive houses. Currently certain building details of passive houses are not perfect or their solution results in higher economic demands related to house purchase and its further use. For the purpose of this thesis details of windows installation in external walls and elimination of thermal bridges in wall footing have been chosen. Products were subject to mathematic modelling of thermal technique and statics. The executed mathematic models documented that products are fully functional and that the suggested product successfully eliminate insufficiencies of some currently applied solutions. 展开更多
关键词 Recycling of materials energy savings ECOLOGY WASTE POLYMER composite thermal bridges.
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New Approach to Ultracapacitor Technology: What it Can Offer to Electrified Vehicles
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作者 Yurii Maletin Natalia Stryzhakova +5 位作者 Sergii Zelinskyi Sergey Chemukhin Dmytro Tretyakov Hugo Mosqueda Natalia Davydenko Dmytro Drobnyi 《Journal of Energy and Power Engineering》 2015年第6期585-591,共7页
Novel carbon-carbon ultracapacitors and hybrid lithium-carbon devices are described. New approach to the design of electrode materials and electrochemical systems followed by the improved design of ultracapacitor cell... Novel carbon-carbon ultracapacitors and hybrid lithium-carbon devices are described. New approach to the design of electrode materials and electrochemical systems followed by the improved design of ultracapacitor cells and modules have resulted in prototypes of superior performance that was verified by independent tests in the Institute of Transportation Studies, UC (ultracapacitor) Davis, in JME Inc., in Wayne State University, and in some other labs. All the test results confirm the superlative performance of the devices developed: carbon-carbon ultracapacitors demonstrate the extremely low inner resistance resulting in the highest power capability and efficiency that also alleviates the cooling requirements and improves safety. Our "parallel" hybrid devices demonstrate substantially higher energy density than competing LIC (lithium ion capacitor) technologies keeping at the same time the high power density, comparable with the best carbon-carbon ultracapacitors available in the market. In order to make ultracapacitor technology even more attractive to automakers, new organic electrolytes (not ionic liquids) have been developed and are currently under testing at temperatures about 100 ℃ and voltages up to 3.0 V. 展开更多
关键词 ULTRACAPACITOR hybrid device high power large energy.
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Pyridinium salt-based covalent organic framework with well-defined nanochannels for efficient and selective capture of aqueous^(99)TcO_(4)^(-) 被引量:7
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作者 Mengjie Hao Zhongshan Chen +3 位作者 Hui Yang Geoffrey I.N.Waterhouse Shengqian Ma Xiangke Wang 《Science Bulletin》 SCIE EI CSCD 2022年第9期924-932,M0004,共10页
Ionic covalent organic framework(COF)materials with high specific surface areas and well-defined pore structures are desired for many applications yet seldom reported.Herein,we report a cationic pyridinium salt-based ... Ionic covalent organic framework(COF)materials with high specific surface areas and well-defined pore structures are desired for many applications yet seldom reported.Herein,we report a cationic pyridinium salt-based COF(PS-COF-1)with a Brunauer-Emmett-Teller(BET)surface area of 2703 m^(2) g^(-1),state-ofthe-art for an ionic COF.Aided by its ordered pore structure,chemical stability,and radiation resistance,PS-COF-1 showed exceptional adsorption properties toward aqueous ReO_(4)^(-)(1262 mg g^(-1))and ^(99)TcO_(4)^(-).Its adsorption performance surpassed its corresponding amorphous analogue.Importantly,PS-COF-1 exhibited fast adsorption kinetics,high adsorption capacities,and selectivity for ^(99)TcO_(4)^(-)and ReO_(4)^(-)at high ionic strengths,leading to the successful removal of ^(99)TcO_(4)^(-)under conditions relevant to low-activity waste streams at US legacy Hanford nuclear sites.In addition,PS-COF-1 can rapidly decontaminate ReO_(4)^(-)/^(99)TcO_(4)^(-)polluted potable water(~10 ppb)to drinking water level(0 ppb,part per billion)within 10 min.Density functional theory(DFT)calculations revealed PS-COF-1 has a strong affinity for ReO_(4)^(-)and ^(99)TcO_(4)^(-),thereby favoring adsorption of these low charge density anions over other common anions(e.g.,Cl^(-),NO_(3)^(-),SO_(4)^(2-),CO_(3)^(2-)).Our work demonstrates a novel cationic COF sorbent for selective radionuclide capture and legacy nuclear waste management. 展开更多
关键词 PERRHENATE PERTECHNETATE Covalent organic frameworks Environmental remediation Anion exchange
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