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减振器生热机理仿真分析

四川大学学报（工程科学版） 2011年第S1期43卷 240-245页

作者：么鸣涛顾亮蒙洋北京理工大学机械与车辆学院北京100081 北京航空航天大学软件学院北京100083

为了准确获知车辆减振器内部温度分布状况,进而为其可靠性设计奠定基础,以某车辆减振器对称性结构特点为依据,建立了具有较高精度的节流阀系流体网格模型。应用计算流体动力学(CFD)数值方法建模,并采用CFX仿真软件对其进行谐波激励下的... 详细信息

为了准确获知车辆减振器内部温度分布状况,进而为其可靠性设计奠定基础,以某车辆减振器对称性结构特点为依据,建立了具有较高精度的节流阀系流体网格模型。应用计算流体动力学(CFD)数值方法建模,并采用CFX仿真软件对其进行谐波激励下的模拟,计算出工作缸管内强迫对流换热的传热过程,进而得出此减振器油液的热量产生过程和温度场分布情况。研究结果表明:外界激励推动油液流经节流阀系过程中产生的摩擦和通过节流阀系之后的涡旋运动导致油液分子间的强烈碰撞,使流经此区域的油液温升迅速。随着热量的传递,减振器内部流场温度逐渐均匀。应用此仿真方法,可明确车辆减振器的温升过程和生热机理,分析结论能为完善减振器温升理论的研究提供参考。

关键词：减振器温度分布强迫对流传热生热机理

Theorem of turbulent intensity and macroscopic mechanism of the turbulence development

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science china Earth sciences 2007年第5期50卷 789-800页

作者： HU YinQiao1,2, CHEN JinBei3,4 & ZUO HongChao2 1 Gansu Province Key laboratory of Arid Climatic Change and Reducing Disaster, Cold and Arid Regions Environment and Engi- neering Institute, Chinese Academy of sciences, Lanzhou 730000, china 2 State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC), beijing 100029, china 3 Atmospheric science college, Lanzhou university, Lanzhou 730000, china 4 Resource Environment Department, Lanzhou Agriculture university, Lanzhou 730060, china Gansu Province Key laboratory of Arid Climatic Change and Reducing Disaster Cold and Arid Regions Environment and Engineering Institute Chinese Academy of Sciences Lanzhou 730000 China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Beijing 100029China Atmospheric science college Lanzhou University Lanzhou 730000 China Resource Environment Department Lanzhou Agriculture University Lanzhou 730060 China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry LAPC Beijing 100029 China

Turbulence is one of the most common nature phenomena in everyday experience, but that is not adequately understood yet. This article reviews the history and present state of development of the turbulence theory and indicates the necessity to probe into the turbulent features and mechanism with the different methods at different levels. Therefore this article proves a theorem of turbulent transpor- tation and a theorem of turbulent intensity by using the theory of the nonequilibrium thermodynamics, and that the Reynolds turbulence and the Rayleigh-Bénard turbulence are united in the theorems of the turbulent intensity and the turbulent transportation. The macroscopic cause of the development of fluid turbulence is a result from shearing effect of the velocity together with the temperature, which is also the macroscopic cause of the stretch and fold of trajectory in the phase space of turbulent field. And it is proved by the observed data of atmosphere that the phenomenological coefficient of turbulent in- tensity is not only a function of the velocity shear but also a function of temperature shear, viz the sta- bility of temperature stratification, in the atmosphere. Accordingly, authenticity of the theorem, which is proved by the theory of nonequilibrium thermodynamics, of turbulent intensity is testified by the facts of observational experiment.

关键词： turbulence nonequilibrium thermodynamics linear thermodynamics atmosphere boundary layer Reynolds turbulence Rayleigh-Bénard turbulence

The Effect of Pre-Deformation at Elevated Temperatures on the Microstructure and Hardness of Boron Steel 22MnB5

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Journal of Iron and Steel Research International 2011年第S1期18卷 600-604页

作者： MIN Jun-ying,LIN Jian-ping,XIN Li-jiu,LI Jia-yue,DING Lei,FENG Qi (college of Mechanical Engineering,Tongji university,Shanghai 201804,china) Tongji Univ Coll Mech Engn Shanghai 201804 Peoples R China

To investigate the effects of the pre-deformation and deformation temperature on the microstructure and hardness of boron steel 22MnB5,isothermal tensile tests were carried out on the Gleeble 3800 system when the temperatures are 700℃,750℃,800℃,*** specimens were employed to obtain different deformation levels at each *** cooling rate before and after deformation was 30℃/*** the microstructures of the specimens were observed and the harness of each specimen was *** results show the martensitic fraction decreases and the ferrite fraction increases with decreasing the deformation temperature or increasing the deformation *** specimens deformed at higher temperature have greater *** hot plastic deformation of austenite shortens the incubation period of ferrite transformation and accelerates the transformation *** addition,the isothermally holding time is longer in the case of a larger deformation amount,more austenite will transform to ***,the specimen deformed at 700℃ and with large deformation has almost full massive ferrite microstructure with larger size.

关键词： 22MnB5 hot pre-deformation microstructure hardness

Molecular Genetic Characterization Of MC4R Coding Region In Chinese Cattle Breeds

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Molecular Genetic Characterization Of MC4R Coding Region In ...

第十次全国畜禽遗传标记研讨会

作者： ZHANG Chun-lei, CHEN Hong, LAN Xian-yong, ZHANG Li, ZHANG Ai-ling (college of Animal science and technology, Northwest A&F university, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Yangling, Shaanxi 712100, china Institute of Cellular and Molecular Biology, Xuzhou normal university, Xuzhou, Jiangsu 221116, china)

Source/description Melanocortin-4 receptor (MC4R) is one of five protein-coupled receptors binding melanocortins that is implicated in the control of ingestive behavior and energy homeostasis. Mutations have been described in the human and mouse MC4R genes which are associated with obesity. Moreover, a mutation in porcine MC4R is associated with economically important traits in the pig. The SNPs reported in bovine MC4R coding region were specific to breeds. In present experiment over 95% of the coding region of MC4R was screened to detect the SNPs in predominantly cattle breeds of *** conditions The 3 primers of PI(275-764), P2 (485-959) and P3 (804-1126) were designed based upon the bovine MC4R sequence (GenBank accession no. AF265221). The 15 μl polymerase chain reaction (PCR) contained 100 ng of genomic bovine DNA, 10 pmol of each primer, dNTPs (200 μM), Tris-HCl pH 8.8 (20 mM), (NH4)2SO4 (50 mM), MgC12 (1.5 mM), and 0.50 U Taq DNA polymerase (TaKaRa, Dalian, china).The cycling protocol was 4 min at 95℃, 35 cycles of 94℃ for 45 min, Annealing 55-63℃ for 45 s, 72 ℃ for 1 min, with a final extension at 72℃ for 4 min. Single stranded conformation polymorphism (SSCP) Aliquots of 5μl of the PCR products were mixed with 5 μl of the denaturing solution (95% formamide, 25 mM EDTA, 0.025% xylene-cyanole and 0.025% bromophenol blue), heated for 10 min at 98℃ and chilled on ice. Denatured DNA was subjected to PAGE (80×73×0.75 mm) in TBE buffer (89 mM Tris-Borate;2 mM EDTA;pH 8.3) and constant voltage (200V) for 2.5 h. The gel was stained with silver nitrate as previous described *** nucleotide polymorphism (SNP) The PCR fragments from different SSCP patterns were cloned and sequenced. Only two SNPs 927C>T and 1069C>G (GenBank #AF265221) were detected in 509 unrelated cattle from five breeds. The mutations 647T>A, 727G>A, 747G>A were not detected in present populations. This confirmed that these SNPs were specific to breeds. Interestingly, the frequency (Table 1)

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一类非正规Cayley有向图

数学学报（中文版） 2003年第1期46卷 103-108页

作者：冯衍全王殿军陈景林北方交通大学数学系北京100044 清华大学数学系北京100084 唐山师范学院数学系唐山063000

本文研究了2p2(p奇素数)阶非交换群上两度Cayley有向图的正规性,发现了一无限族非正规的Cayley有向图.

关键词： Cayley图正轨Cayley有向图有限群

马克思主义早期中国化的一个视角——李大钊劳工教育思想对国际工人运动理论的探索与发展

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高校社科动态 2008年第5期 28-34页

作者：田海林徐文杰山东师范大学历史文化与社会发展学院北京师范大学政治学与国际关系学院

20世纪20年代,伴随着马克思主义在中国的广泛传播和中国共产党的成立,工人运动也在中国兴起。李大钊结合中国的实际,对国际工人运动理论进行了有益的探索,形成了独特的劳工教育思想。这一思想具有深厚的社会背景和独特的思想渊源,是一... 详细信息

20世纪20年代,伴随着马克思主义在中国的广泛传播和中国共产党的成立,工人运动也在中国兴起。李大钊结合中国的实际,对国际工人运动理论进行了有益的探索,形成了独特的劳工教育思想。这一思想具有深厚的社会背景和独特的思想渊源,是一个内容上熔知、情、义三种教育于一炉,目标上集政治革命、社会进步和人的完善于一体的思想体系。这既是其哲学思想、政治思想、教育思想和社会伦理思想综合作用的产物,也是其自觉运用马克思主义原理解决中国社会问题初步探索的成果之一,是马克思主义在中国实现民族化和具体化的开端。

关键词：李大钊劳工劳工教育

Study on Responsible college Tourism Education to Preserve Cultural Heritage in Xinjiang

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Study on Responsible College Tourism Education to Preserve C...

地理学核心问题与主线——中国地理学会2011年学术年会暨中国科学院新疆生态与地理研究所建所五十年庆典

作者： Guan Liping~(a,b,c) Yang Zhaoping~a (a Xinjiang Institute of Ecology and Geography,CAS, Urumqi,830011 b Graduate School of Chinese Academy of science,beijing 100049 c School of Geographic science and Tourism,Xinjiang normal university,Urumqi, 830014)

Xinjiang is an exclusive place in the world where the four ancient civilizations of china,Arab,India and Greek *** by mingle of four ancient civilizations,tangible and intangible cultural relics in Xinjiang created the special tourism settings and unique destination for *** arrivals particularly the outbound ones rushing into Xinjiang practice behaviours which bring seriously negative affluences on the cultural heritages in addition to the positive *** an industry, tourism is economically identified;however cultural heritage emphasizes conservation and *** between cultural heritage conservation and tourism development are outstanding obstacle for their sustainable *** key of peaceful solution to conflicts between cultural heritage conservation and tourism development is the cultivation of responsible stakeholders such as community, tour guide,tourists,administrative bodies,*** college education is a distinguished factor in the cultivation of responsible tourism stakeholders and *** paper reviewed some related literatures which stated the importance of college education in the preservation of heritage and their ***,it investigated the situation of college education of tourism in the preservation of cultural heritage in Xinjiang by *** found not a course immediately about relations between cultural heritage and tourism was listed in the curriculums;it failed to inculcate students with awareness of sustainable utilization of cultural heritage as tourism resources;and it did not keep up with the need of tourism development on cultural heritage with rapid expansion but low efficiency and limited improvement in educational *** paper suggested that universities in Xinjiang apply directly related discipline and not just change the existing curriculum structure to extend the channels to meet the needs of the students and society;universities take active part

关键词： responsible college tourism education cultural heritage Xinjiang

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摩擦市场的最优消费-投资组合选择

系统科学与数学 2004年第3期24卷 406-416页

作者：李仲飞汪寿阳中山大学岭南学院金融系广州510275 中国科学院数学与系统科学研究院系统科学研究所北京100080

本文研究摩擦市场中的最优消费-投资组合选择问题.当金融资产和自然状态个数为有限个以及摩擦局限于成比例的交易费时,可用原始市场或适当转换了的市场的无套利性来刻画最优消费-投资组合策略的存在性或充要条件.

关键词：摩擦市场最优消费-投资组合交易费无套利分析

夜鹭(Nycticorax nycticorax)的繁殖、生长和恒温能力发育的研究

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信阳师范学院学报（自然科学版） 1991年第4期4卷 92-104页

作者：文祯中孙儒泳

1990年2月——1991年7月在牌坊鸟岛观察了26窝87只雏夜鹭。该鸟三月下旬迁来营巢,产卵3——5枚(平均3.35),卵均重31.77g,k_w=0.500。孵化期21——26天(平均23.2),孵化率高达92.68％,孵化期卵失水率24.27％,育雏期30——35天。25日令雏... 详细信息

1990年2月——1991年7月在牌坊鸟岛观察了26窝87只雏夜鹭。该鸟三月下旬迁来营巢,产卵3——5枚(平均3.35),卵均重31.77g,k_w=0.500。孵化期21——26天(平均23.2),孵化率高达92.68％,孵化期卵失水率24.27％,育雏期30——35天。25日令雏鸟体重达成鸟的88.14％,其体重生长模型为w_t=516.8481/(1+e^(2.7555-0.2389t))。恒温发育分三期:①1——4天为迅速发育期,②4——19天为缓慢上升期,③19天后为恒温建立期,雏鸟食性为蛙(48％)、泥鳅(35％)和鱼(17％)。

关键词：夜鹭繁殖生长鹭科鸟类发育