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Journal of Thermal Science 2019年第3期28卷 494-504页

作者： liu Peng shu Gequn tian Hua State Key Laboratory of Engines Tianjin University

In consideration of the high-temperature characteristic of engine's waste heat and stricter environmental regulations, natural substance, including CO_2 and hydrocarbons, have been treated as promising working fluid for diesel engine waste heat recovery due to its environment friendly and excellent physical and chemical properties. This paper presented a comprehensive performance analysis on transcritical Rankine cycles for diesel engine multiple waste heat recovery using hydrocarbons and CO_2 as working fluid. The optimal turbine inlet pressures corresponding to maximum net power output, maximum exergy efficiency and minimum electricity production cost(EPC) were obtained. The effect of working fluid on these optimal pressures has been discussed. For fluids with low critical temperature, the optimal pressure corresponding to maximum net power output is lower than the one for maximum exergy efficiency, while the opposite results can be found for fluid with high critical temperature. Then, the effect of various working fluid properties in transcritical cycle performance is discussed. Comparison results show that CO_2 obtains only more power output than Ethane, Propane and Propene, but CO_2 is capable of absorbing more energy from engine coolant and regeneration heat with comparable total heat transfer areas and has an advantage in turbine size, particularly for hydrocarbons with high critical temperature.

关键词： transcritical Rankine cycle natural working fluid multiple waste heat performance comparison

多学科协作模式对结肠癌患者住院费用、平均住院日、并发症发生率的影响

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中国现代医学杂志 2016年第13期26卷 138-140页

作者：刘清安肖泽民郭敏刘书田杨利民陈新文刘海军湖南省常德市第一人民医院湖南常德415000

目的探讨多学科协作(MDT)对结肠癌患者住院费用、住院时间及并发症发生率的影响。方法选取该院收治的124例结肠癌患者为研究对象,分为MDT组和非MDT组,分析比较两组患者的住院费用、住院日期及并发症的发生情况。结果 MDT组患者的住院费... 详细信息

目的探讨多学科协作(MDT)对结肠癌患者住院费用、住院时间及并发症发生率的影响。方法选取该院收治的124例结肠癌患者为研究对象,分为MDT组和非MDT组,分析比较两组患者的住院费用、住院日期及并发症的发生情况。结果 MDT组患者的住院费用和住院时间均少于非MDT组(P<0.05);MDT组患者治疗过程中呼吸衰竭、肺部感染及切口感染的发生率低于非MDT组患者(P<0.05)。结论多学科协作治疗模式能够有效优化治疗过程,促进患者恢复,减少住院费用及住院日期,同时减少并发症的发生。

关键词：多学科协作结肠癌住院费用住院时间并发症

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干细胞的趋电性迁移及机制

中国组织工程研究 2025年第23期29卷 4984-4992页

作者：韩芳舒晴贾绍辉田峻武汉体育学院运动医学院湖北省武汉市430079 武汉大学中南医院骨科康复科湖北省武汉市430071

背景:随着对干细胞技术研究的深入,如何使其准确归巢成为临床应用中的一大难题。除药物和趋化因子等信号的诱导外,电场也被广泛应用于指导干细胞的定向迁移,并可增强其迁移速度和定向性。目的:旨在分析总结电场对干细胞迁移特性的影响,... 详细信息

背景:随着对干细胞技术研究的深入,如何使其准确归巢成为临床应用中的一大难题。除药物和趋化因子等信号的诱导外,电场也被广泛应用于指导干细胞的定向迁移,并可增强其迁移速度和定向性。目的:旨在分析总结电场对干细胞迁移特性的影响,同时综述可能的作用机制。方法:通过检索Pub Med和中国知网数据库,收集截至2024年3月的相关文献,英文检索词:“stem cells,direct current electric field,pulsed electric field,migration,electric field device,mechanism”;中文检索词:“干细胞,直流电场,脉冲电场,迁移,电场装置,机制”。排除不能获取全文和与主题无关的文献。结果与结论:根据筛选要求共纳入58篇文献,包括中文文献15篇及英文文献43篇。文献以脂肪间充质干细胞、骨髓间充质干细胞、神经干细胞、表皮干细胞、人胚胎干细胞和人诱导性多功能干细胞为研究对象,在迁移装置中研究电场的不同参数对上述干细胞迁移的影响及其机制。(1)电场作为一种简单、无创且稳定的干预方式在指导干细胞定向迁移的过程中起着积极作用;(2)不同类型的干细胞发生趋电性迁移的方向不同,同时大部分干细胞的迁移速度和定向性是随着电场强度增加而增加的;(3)不同的电场装置在观测干细胞迁移时的侧重点不同,可根据实验目的而择优选择相关装置;(4)不同干细胞趋电性迁移的机制不完全相同,多数干细胞迁移过程中有MAPK通路、ROCK活化以及PI3K功能的参与,同时还有其他蛋白质复合物与信号通路参与调控该过程;(5)除电场参数不同之外,细胞本身的衰老情况和培养环境也会对趋电性迁移的结果产生影响。总而言之,电场作为一种影响干细胞迁移特性的重要信号,与其他新兴材料结合在组织工程应用中展现出了一定的潜力,有望在指导干细胞归巢方面发挥更加重要的作用,促进骨组织再生和修复以及神经系统、自身免疫系统以及肿瘤等疾病的研究取得更大的突破。

关键词：干细胞电场趋电性迁移机制归巢效应物理因子电场装置细胞衰老培养环境

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运用知识经济观念发展水电事业

西北水电 2001年第4期 60-62页

作者：田树棠刘国锋国家电力公司西北勘测设计研究院西安710065

知识经济是以知识为基础的经济。知识经济是指区别于以往的以传统工业为产业结构 ,以稀缺自然资源为主要依托的新型经济。水电事业虽是传统的工业经济 ,但其开发利用的不是稀缺自然资源而是水 ,从能源配置上来看 ,水电事业带有知识经济... 详细信息

知识经济是以知识为基础的经济。知识经济是指区别于以往的以传统工业为产业结构 ,以稀缺自然资源为主要依托的新型经济。水电事业虽是传统的工业经济 ,但其开发利用的不是稀缺自然资源而是水 ,从能源配置上来看 ,水电事业带有知识经济成分。要利用科技知识、管理科学与行为科学知识 ,来更好地开发水电事业 ,尤其是黄河上游水电资源。

关键词：知识经济水电事业水电资源水电开发黄河上游

MANAGING REDISTRIBUTION OF TOLL REVENUE WITH USER HETEROGENEITY

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Journal of Systems Science and Systems Engineering 2014年第3期23卷 330-342页

作者： shu-Xian Xu tian-Liang liu Hai-Jun Huang School of Economics and Management Beihang University

With the explicit consideration of user heterogeneity, i.e., each user has a different value of time （VOT）, this paper examines the system efficiency and social equity of toll revenue redistribution in a bi-mode transportation system. Three schemes of distributing the road toll revenue are proposed, which respectively consider efficiency, equity, as well as efficiency and equity together. With mild assumptions, we prove that the number of auto-motorists decreases and the total social cost increases with transit subsidy share when only marginal operating cost of the transit is covered by its fare. However, when average fixed cost of the transit is further covered, the total social cost is a ＂U＂ shape curve against the transit subsidy share. Numerical results show that the well designed toll revenue redistribution schemes can make the system more equitable while keeping high efficiency. With the increase of user heterogeneity, the Gini coefficient becomes larger while the total social cost goes down.

关键词： Mode choice value of time toll revenue redistribution efficiency equity

Analysis of an electricity-cooling cogeneration system for waste heat recovery of gaseous fuel engines

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Science China(Technological Sciences) 2015年第1期58卷 37-46页

作者： shu GeQun WANG Xuan tian Hua LIANG YouCai liu Yu liu Peng State Key Laboratory of Engines Tianjin University

Waste heat recovery(WHR)is one of the most useful ways to improve the efficiency of internal combustion engines,and an electricity-cooling cogeneration system(ECCS)based on Rankin-absorption refrigeration combined cycle for the WHR of gaseous fuel engines is proposed in the *** system can avoid wasting the heat in condenser so that the efficiency of the whole WHR system improves,but the condensing temperature of Rankin cycle(RC)must increase in order to use absorption refrigeration system,which leads to the decrease of RC output ***,the relationship between the profit of absorption refrigeration system and the loss of RC in this combined system is the mainly studied content in the *** the energy quality of cooling and electricity are different,cooling power in absorption refrigeration is converted to corresponding electrical power consumed by electric cooling system,which is defined as equivalent electrical *** this method,the effects of some important operation parameters on the performance of the ECCS are researched,and the equivalent efficiency,exergy efficiency and primary energy rate are compared in the paper.

关键词： gaseous fuel engines waste heat recovery electricity-cooling cogeneration Rankin cycle absorption refrigeration

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长江靖江段沿岸似鳊生长及种群参数估算

长江流域资源与环境 2017年第9期26卷 1369-1377页

作者：郭弘艺魏凯唐文乔张旭光周天舒刘东李辉华沈林宏上海海洋大学海洋动物系统分类与进化上海高校重点实验室上海201306 北京市水生野生动植物救护中心北京102100 江苏省靖江市渔政管理站江苏靖江214500

2012年1月~2013年12月连续24个月在长江靖江段沿岸收集似鳊标本2 334尾,采用基于体长频率数据的ELEFAN I技术估算长江近口段沿岸似鳊的生长参数与种群参数。结果表明:似鳊体长(L,cm)与体质量(W,g)幂函数关系为:W=0.0182×L^(2.948)(r=0.... 详细信息

2012年1月~2013年12月连续24个月在长江靖江段沿岸收集似鳊标本2 334尾,采用基于体长频率数据的ELEFAN I技术估算长江近口段沿岸似鳊的生长参数与种群参数。结果表明:似鳊体长(L,cm)与体质量(W,g)幂函数关系为:W=0.0182×L^(2.948)(r=0.9823,n=2334)。Von Bertalanffy生长方程描述的似鳊生长参数为:极限体长(L_∞)=19.25 cm,生长系数(K)=0.2/a,理论生长起点年龄(t_0)为-1.59 a,体质量的生长拐点年龄为3.55 a。采用Pauly的经验公式估算似鳊自然死亡系数(M)为0.556/a。由长度变换渔获曲线法估算出的似鳊总死亡系数(Z)为1.638/a,捕捞死亡系数(F)和开发率(E)分别为1.082/a和0.66/a。2012~2013年长江靖江段沿岸似鳊年均资源重量和资源数量分别为120.59 t和947.4万尾。经相关估算参数和相对单位补充渔获量分析得出,当前长江靖江段沿岸似鳊已处于过度捕捞状态。建议将沿岸水域禁渔期延长至9月(即4~9月),以实现似鳊资源的恢复和可持续发展。

关键词：长江靖江段似鳊生长参数死亡参数

SENP2 negatively regulates cellular antiviral response by deSUMOylating IRF3 and conditioning it for ubiquitination and degradation

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Journal of Molecular Cell Biology 2011年第5期3卷 283-292页

作者： Yong Ran tian-tian liu Qian Zhou shu Li Ai-Ping Mao Ying Li Li-Juan liu Jin-Ke Cheng Hong-Bing shu College of Life Sciences Wuhan UniversityWuhan 430072China Department of Biochemistry and Molecular Cell Biology School of MedicineShanghai Jiao Tong UniversityShanghai 200025China

Transcription factor IRF3-mediated type I interferon induction is essential for antiviral innate *** identified the deSUMOylating enzyme Sentrin/SUMO-specific protease(SENP)2 as a negative regulator of virus-triggered IFN-b *** of SENP2 caused IRF3 deSUMOylation,K48-linked ubiquitination,and degradation,whereas depletion of SENP2 had opposite *** the SUMOylation and K48-linked ubiquitination of IRF3 occurred at lysines 70 and 87,and these processes are *** level of virus-triggered IFN-b was markedly up-regulated and viral replication was reduced in SENP2-deficient cells comparing with wild-type *** findings suggest that SENP2 regulates antiviral innate immunity by deSUMOylating IRF3 and conditioning it for ubiquitination and degradation,and provide an example of cross-talk between the ubiquitin and SUMO pathways in innate immunity.

关键词： SENP2 IRF3 deSUMOylation ubiquitination innate immunity

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苓桂甘枣汤对家兔排尿作用实验研究

时珍国医国药 2002年第6期13卷 344-346页

作者：孙维敏胡邦仁田树革刘波刘浩刘新新疆医科大学中医学院新疆乌鲁木齐830054

目的 :实验观察苓桂甘枣汤对家兔排尿作用。方法 :家兔用生理盐水灌胃 (5 0 ml/只 ) ,10 min后以苓桂甘枣汤水煎液灌胃 (10 ml/kg体重 ) ,BL - 410生物机能实验系统记录排尿量。同样方法以生理盐水、呋塞米片为对照。结果 :4 h内平均每... 详细信息

目的 :实验观察苓桂甘枣汤对家兔排尿作用。方法 :家兔用生理盐水灌胃 (5 0 ml/只 ) ,10 min后以苓桂甘枣汤水煎液灌胃 (10 ml/kg体重 ) ,BL - 410生物机能实验系统记录排尿量。同样方法以生理盐水、呋塞米片为对照。结果 :4 h内平均每只家兔排尿量苓桂甘枣汤组 (10 78± 2 93)滴大于生理盐水组(5 78± 32 0 )滴 ,差异显著 (t=3.0 4 84 ) ,低于呋塞米片组 (135 1± 5 79)滴 (t=- 1.112 8) ,差异无显著意义。结论 :苓桂甘枣汤对家兔排尿作用近似于呋塞米片。

关键词：排尿作用实验研究苓桂甘枣汤家兔利尿

On a Generalized Extended F-Expansion Method

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Communications in Theoretical Physics 2006年第1期45卷 15-28页

作者： REN Yu-Jie liu shu-tian ZHANG Hong-Qing Department of Applied Mathematics Dalian University of Technology Dalian 116024 China Department of Mathematics and Physics Dalian Institute of Light Industry Dalian 116034 China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian 116024 China

Making use of a new generalized ansatz, we present a new generalized extended F-expansion method for constructing the exact solutions of nonlinear partial differential equations in a unified way. Applying the generalized method with the aid of Maple, we consider the （2＋1）-dimentional breaking soliton equation. As a result, we successfully obtain some new and more general solutions including Jacobi elliptic function solutions, soliton-like solutions, trigonometric function solutions, and so on. As an illustrative sampler the properties of some soliton solutions for the breaking soliton equation are shown by some figures. Our method can also be applied to other partial differential equations.

关键词： (2+1)-dimentional breaking soliton equation generalized extended F-expansion method Jacobi elliptic function solution generalized ansatz soliton-like solution