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Laminar Flow in the Gap between Two Rotating Parallel Frictional Plates in Hydro-viscous Drive

Chinese Journal of Mechanical Engineering 2012年第1期25卷 144-152页

作者： HUANG Jiahai wei jianhua QIU Minxiu The State Key Lab of Fluid Power Transmission and Control Zhejiang UniversityHangzhou 310027China

The velocity, pressure and temperature distributions of the flow in the gap between hydro-viscous drive friction disks are the key parameters in the design of hydro-viscous drive and angular velocity controller. In the previous works dealing with the flow in the gap between disks in hydro-viscous drive, few authors considered the effect of Coriolis force on the flow. The object of this work is to investigate the flow with consideration of the effects of centrifugal force, Coriolis force and variable viscosity. A simplified mathematical model based on steady and laminar flow is presented. An approximate solution to the simplified mathematical model is obtained by using the iteration method assuming that the fluid viscosity remains constant. Then the model considering the effect of variable viscosity is solved by means of computational fluid dynamics code FLUENT. Numerical results of the flow are obtained. It is found that radial velocity profile diverges from the ideal parabolic curve due to inertial forces and tangential velocity profile is nonlinear due to Coriolis force, and pressure has two possible solution branches. In addition, it is found that variable viscosity plays an important role on pressure profiles which are significantly different from those of fluid with constant viscosity. The experimental device designed for this work consists of two disks, and one of them is fixed. Experimental pressure and temperature of the flow within test rig are obtained. It is shown that the trend of numerical results is in agreement with that of experimental ones. The research provides a theoretical foundation for hydro-viscous drive design.

关键词： hydro-viscous drive rotating disks flow inertial force viscosity-temperature characteristics

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姜黄素天然高分子智能活性包装膜研究进展

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食品与发酵工业 2024年第9期50卷 348-355页

作者：黄星海韦建华钟海艺广西中医药大学药学院广西南宁530200

随着人民大众对食品安全和质量的要求不断提高,食品保鲜技术得到了迅速地发展,其中食品智能活性包装膜成为研究的重点。姜黄素是从姜黄根茎中提取分离得到的黄色多酚类化合物,是一种具有抗菌、抗氧化、pH响应性等特点的中药化学成分,研... 详细信息

随着人民大众对食品安全和质量的要求不断提高,食品保鲜技术得到了迅速地发展,其中食品智能活性包装膜成为研究的重点。姜黄素是从姜黄根茎中提取分离得到的黄色多酚类化合物,是一种具有抗菌、抗氧化、pH响应性等特点的中药化学成分,研究人员根据姜黄素的特性研发了一系列负载姜黄素的智能活性包装膜。高分子材料因良好的力学性能、可降解性和生物相容性越来越受到研究者的关注,已被广泛作为智能活性包装膜的基材。该文对负载姜黄素的天然高分子智能包装膜或活性包装膜在食品保鲜领域中的应用进行综述,为中药化学成分姜黄素在食品保鲜领域中的进一步开发和应用提供一定的参考。

关键词：姜黄素智能包装膜活性包装膜天然高分子食品保鲜

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Dynamic Per-flow Queuing to Reduce Competitions Among Large Number of Flows

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Chinese Journal of Electronics 2014年第4期23卷 783-789页

作者： wei jianhua ZHU Lei ZHANG weichuan FENG Zhi GUO Peng Electronics and Information College Xi'an Polytechnic University

Per-flow queuing is believed to be able to guarantee advanced Quality of service(Qo S) for each flow at high speed routers. With the dramatic increase for both link speed and number of traffic flows, per-flow queuing confronts a great challenge, since millions of queues need to be maintained for implementation in a traditional sense. In this paper, setting only a small number of physical queues,we propose a Dynamic per-flow queuing(DPFQ) mechanism that achievesthe same performance as per-flow queuing at a cost of an additional Binary content addressable memory(BCAM). The proposed mechanism works due to the fact that the number of simultaneous active flows at a mini-time scale in the router buffer is much smaller than that of in-progress flows. In DPFQ, a physical queue is created on demand when a new flow comes, and released when the flow temporarily pauses or finishes. A small BCAM is occupied to map flows to queues, so as to guarantee that only the packets from the same flow are buffered in any assigned queue. Through analysis and simulation we show that using a small number of physical queues,DPFQ achieves both low operation delay and power consumption.

关键词： Packet buffers Memory management Per-flow queuing

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Virus-induced silencing of a tobacco deoxyhypusine synthase gene

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Chinese Science Bulletin 2005年第23期50卷 2707-2713页

作者： WANG Hongzhi MA Rongcai LI Ruifen WANG Guoying wei jianhua State Key Laboratory for Agrobiotechnology China Agricultural University Beijng 100094 China Beijing Agro-Biotechnology Research Center Beijing Academy of Agriculture and Forestry Science Beijing 100089 China

A cDNA fragment corresponding to deoxyhy-pusine synthase gene NbDHS was isolated and cloned into potato virus X (PVX) vector for functional analysis in Nico-tiana benthamiana by using virus-induced gene silencing (VIGS). Plants agroinfected with recombinant virus vector PVX-NbDHS exhibited an increase in leaf biomass, delay in natural leaf senescence and flowering time, and decrease in leaf chlorophyll content. Semi-quantitative RT-PCR and Northern analysis showed that the transcript level of DHS was significantly lower in PVX-NbDHS infected plants. At the same time, the expression for eIF-5A, the target proteins of DHS in N. benthamiana, was concomitantly suppressed by semi-quantitative RT-PCR and Western analysis. From the phenotypic feature of the infected plants and the reduced expression abundance of DHS and eIF-5A, we concluded that NbDHS plays important roles in plant growth, development and senescence. The possible application of DHS gene in ge-netic modification of crops and horticultural plants was dis-cussed.

关键词：烟草脱氧羟腐胺缩赖氨酸合酶基因基因克隆生长促进作用

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下咽-食道同时性多原发癌伴Ⅲ度喉梗阻患者围手术期护理

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中华急危重症护理杂志 2024年第2期5卷 156-158页

作者：孙春蓉张萍卫建华浙江大学医学院附属第一医院耳鼻咽喉科杭州市310003 浙江大学医学院附属第一医院外科监护室杭州市310003

总结1例下咽-食道同时性多原发癌伴Ⅲ度喉梗阻患者围手术期护理体会。针对患者气道高风险、病情进展迅速、肺部感染、全身营养状态差、运动功能衰弱等问题,采取气道梗阻风险预警及应急处理,阶段化实施肺保护性策略,以目标为导向的术前... 详细信息

总结1例下咽-食道同时性多原发癌伴Ⅲ度喉梗阻患者围手术期护理体会。针对患者气道高风险、病情进展迅速、肺部感染、全身营养状态差、运动功能衰弱等问题,采取气道梗阻风险预警及应急处理,阶段化实施肺保护性策略,以目标为导向的术前预康复营养管理,低负荷小强度个体化抗阻运动改善虚弱促进患者康复等措施。经过34 d的积极治疗与护理,患者病情稳定出院,出院后随访1个月,患者状态良好。

关键词：下咽肿瘤食管肿瘤肿瘤多原发性围手术期护理

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Lignin biosynthesis by suppression of two O-methyl-transferases

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Chinese Science Bulletin 2002年第13期47卷 1092-1095,1145页

作者： ZHAO Huayan wei jianhua ZHANG Jinyu LIU Huirong WANG Tai SONG Yanru Institute of Botany Chinese Academy of SciencesBeijing 100093China Beijing Center of Agro-Biotechnology Beijing Institute of Agriculture and ForestryBeijing 100089China 不详

Caffeic acid O-methyltransferase (COMT) and caffeoyl-CoA-3-O-methyltransferase (CCoAOMT) genes encode two methyltransferases at different substrate levels in lignin biosynthesis. We constructed two single antisense expression vectors containing the cDNA of COMT or CCoAOMT genes and one dual antisense expression vector containing cDNAs of both OMTs genes. The antisense constructs were transferred into tobacco mediated by Agrobac-terium tumefacience. PCR-Southern analysis indicated that antisense cDNAs had been integrated into the genome of the transgenic tobacco. The antisense genes were also expressed at transcriptional level displayed by Northern dot analysis. Klason lignin assay of 3-month-old transgenic tobaccos showed that repression in COMT or CCoAOMT alone could result in reduction of lignin content, more reduction was caused by suppression in CCoAOMT than in COMT. Furthermore, simultaneous suppression of both COMT and CCoAOMT resulted in more reduction than that of single gene, which indicated

关键词： COMT CCoAOMT antisense RNA lignin histochemi-cal staining.

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四氯乙烯中毒患者行中西医结合促进毒物排泄的急救护理

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中华急危重症护理杂志 2024年第1期5卷 55-57页

作者：林振华卫建华邹吉涛浙江省立同德医院急诊科杭州市310010 浙江大学附属第一医院外科监护室

总结1例口服四氯乙烯中毒继发多脏器功能不全患者的急救护理体会。针对患者所服毒物具有多通道吸收、病情进展迅速,需快速、彻底清除毒物的同时保护脏腑功能的特点,采取消化道-呼吸道-皮肤-脏腑序贯式清除毒物策略、大潮气量机械通气策... 详细信息

总结1例口服四氯乙烯中毒继发多脏器功能不全患者的急救护理体会。针对患者所服毒物具有多通道吸收、病情进展迅速,需快速、彻底清除毒物的同时保护脏腑功能的特点,采取消化道-呼吸道-皮肤-脏腑序贯式清除毒物策略、大潮气量机械通气策略促进毒物清除、肺部超声动态评估预防气压伤,以及可视化中药洗胃预防误吸等针对性护理措施。经过中西医结合全面、高效的急救和护理,患者病情好转,于入院6 d后出院,出院1个月随访无异常。

关键词：四氯乙烯中毒超声检查多普勒洗胃中西医结合疗法急症护理

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ICU感控护士在医院感染防控中的专业价值及启示

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中国护理管理 2024年第1期24卷 18-23页

作者：王华芬翁峰霞桑明卫建华李志茹浙江大学医学院附属第一医院护理部杭州市310003 浙江大学医学院附属第一医院外科监护室杭州市310003

通过对ICU感控护士的发展现状、5种专业价值角色(教育者、管理者、联络者、监测者、研究者)进行综述,提出发展我国ICU感控护士的思考与启示,包括重视其临床价值,明确其角色及职能,完善其培训和考核体系,从而为未来我国的感控护理人才队... 详细信息

通过对ICU感控护士的发展现状、5种专业价值角色(教育者、管理者、联络者、监测者、研究者)进行综述,提出发展我国ICU感控护士的思考与启示,包括重视其临床价值,明确其角色及职能,完善其培训和考核体系,从而为未来我国的感控护理人才队伍建设提供借鉴,更好地发挥ICU感控护士在医院感染防控中的作用,以期为有效降低ICU感染的发生率,改善ICU患者生存结局提供依据,进一步引领我国医院感染防控走向专业化的发展轨道。

关键词：重症监护室感控护士医院感染专业价值综述

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Pulping performance of transgenic poplar with depressed Caffeoyl-CoA O-methyltransferase

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Chinese Science Bulletin 2008年第22期53卷 3553-3558页

作者： wei jianhua WANG YanZhen WANG HongZhi LI RuiFen LIN Nan MA RongCai QU LeQing SONG YanRu Beijing Agro-Biotechnology Research Center Beijing Academy of Agriculture and Forestry Sciences Beijing 100097 China Institute of Botany Chinese Academy of Sciences Beijing 100093 China

This paper evaluated pulping performance of 3-year-old field-grown transgenic poplar (Populus tremula × Populus alba). The transgenic poplar with anti-sense CCoAOMT had an about 13% decreased lignin content, in which a slight increment was found in S/G ratio. Chemical analysis showed that the transgenic poplar had significantly less benezene-ethanol extractive than that of control wood, but no significant differences were found in contents of ash, cold water extractive, hot water extractive, 1% NaOH extractive, holocellulose, pentosans and cellulose. Fiber assay demonstrated that down-regulation of CCoAOMT expression improved the fiber quality in transgenic poplar. Kraft pulping showed that lower lignin in transgenic poplar led to remarkable improved pulp quality and increased pulp yield.

关键词：白杨 CCoAOMT 制浆过程甲基转化酶

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前撑注浆钢管在某超大软土基坑中的应用

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工程勘察 2024年第3期52卷 24-28页

作者：海明雷魏建华上海勘察设计研究院(集团)有限公司上海200093

前撑注浆钢管是上海及周边软土地区近年来应用的一种新型基坑支撑形式,与常规的内支撑体系相比,具有施工便捷、挖土方便和造价经济等优点,应用在大面积基坑中具有明显的优势。本文以上海某超大基坑项目为背景,详细介绍了前撑注浆钢管在... 详细信息

前撑注浆钢管是上海及周边软土地区近年来应用的一种新型基坑支撑形式,与常规的内支撑体系相比,具有施工便捷、挖土方便和造价经济等优点,应用在大面积基坑中具有明显的优势。本文以上海某超大基坑项目为背景,详细介绍了前撑注浆钢管在具体工程项目中的应用情况。项目的成功实施,对于软土地区类似的超大基坑工程具有较高的参考意义。

关键词：软土基坑围护前撑注浆钢管内支撑

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