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Correlation between Temperature and Velocity Fluctuations in the Near-Wall Region of Rotating Turbulent Channel Flow

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Chinese Physics Letters 2012年第5期29卷 161-164页

作者： ANG Zi-xuan CUI Gui-Xiang xu chun-xiao ZHANG Zhao-Shun SHAO Liang Department of Engineering Mechanics Tsinghua UniversityBeijing 100084 Laboratory of Fluid Mechanics and Acoustics Ecole Centrale de LyonFrance

The correlation between the temperature and streamwise velocity fluctuations in rotating turbulent channel flow is *** the previously found analogous property between the statistics of the temperature and streamwise velocity fluctuations,the correlation can more appropriately reveal the similarity between two random processes. The analysis of the correlation coefficient obtained from the database of direct numerical simulation indicates that the rotation weakens the correlation in most regions of the flow,especially on the suction ***,the correlation is slightly enhanced by the rotation in some regions of the rotating channel,which challenges the general understanding that rotation undoubtedly weakens the *** discuss the mechanism of the rotating effect on the correlation,the transport equations of the variance of temperature and streamwise velocity fluctuations are considered. The Coriolis force is found to have an indirect effect on the correlation.

关键词： rotating rotation analogous

Precipitates and Hydrogen Permeation Behavior in Vanadium-Bearing Microalloyed Low Carbon Steel

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Journal of Iron and Steel Research International 2011年第S1期18卷 290-295页

作者： xu chun,LI xiao-jie,SHEN Da-guang (Material Engineering Department,Shanghai Institute of Technology,Shanghai 200233,China) Shanghai Inst Technol Dept Mat Engn Shanghai 200233 Peoples R China

The precipitates and hydrogen permeation behavior were studied in the low carbon steel for *** the preparation of samples,Ti containing and Ti free in vanadium-bearing microalloyed low carbon steel heating at 750℃ for 3 h,were adopted after *** was found that the a large number of fine VC,TiC,TiN and Ti 4 C 2 S 2 precipitates were in samples of Vanadium-bearing microalloyed low carbon steel with Ti *** fine VC,Fe 3 C and MnS precipitates were in steels without Ti *** the numbers of precipitates in the former is more bigger than the *** activation energies for hydrogen diffusion in both samples are 26.5 and 23.7 kJ/mol,*** at 25℃,the effective diffusion coefficients in the samples for Ti containing and Ti free in Vanadium-bearing microalloyed low carbon steel were measured as 2.71×10-6 and 4.22×10-6 cm 2 /s,*** fishscaling defect occurred in the former and heavy fishscaling defect in the later.

关键词： precipitate hydrogen permeability enameling vanadium-bearing microalloyed low carbon steel

MODELLING THE POLYALANINE BACKBONE STARTING FROM ALPHA-CARBON GUIDE POSITIONS

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Chinese Chemical Letters 1990年第1期1卷 87-90页

作者： Yu LUO xu Liang JIANG Lu Hua LAI chun xu QU xiao Jie xu You Qi TANG Institute of Physical Chemistry,Peking University,Beijing 100871

An automatic procedure for building a protein polyalanine backbone from guiding alpha-carbon positions is presented here,which is different from a previously developed'spare parts'approach(Jones and Thirup,1986;Claessens et al.,1989). In our procedure,the geometric restraint of angle N-CA-C is used to generate a list of polypeptide chains,and several filters are used later to select the best *** most important filter is based upon the Ramachandran scatter plot of mainchain dihedral angles PHI and *** for all test cases are satisfactory,with more than 95%of peptide planes correctly reconstructed and the overall root-mean-square deviation less than 0.5 angstrom compared with the refined X-ray coordinates.

关键词： Bank MODELLING THE POLYALANINE BACKBONE STARTING FROM ALPHA-CARBON GUIDE POSITIONS length maps

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红色旅游的业态群落发育研究

商业经济与管理 2014年第5期 51-59页

作者：许春晓湖南师范大学旅游学院湖南长沙410081

新时期红色旅游与相关产业共生发展,业态群落不断成长,对经济社会发展促进意义显著。文章用思辨方法,界定旅游业态的概念并确定其类、型、种的类型体系,归纳红色旅游业态发育的动力因素和动力机制。依据旅游业态类型在业态群落中的地位... 详细信息

新时期红色旅游与相关产业共生发展,业态群落不断成长,对经济社会发展促进意义显著。文章用思辨方法,界定旅游业态的概念并确定其类、型、种的类型体系,归纳红色旅游业态发育的动力因素和动力机制。依据旅游业态类型在业态群落中的地位,其表现出园区场群落、生活馆群落、实体超市群落和流量平台群落依次演进的特征。以韶山红色旅游区的业态群落发育历程做了印证性研究。

关键词：红色旅游业态业态类型动力因素动力机制业态群落

Effects of eukaryotic expression plasmid encoding human tumstatin gene on endothelial cells in vitro

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Chinese Medical Journal 2010年第16期123卷 2269-2273页

作者： YANG Ya-pei xu chun-xiao HOU Guo-sheng XIN Jia-xuan WANG Wei LIU Xian-xi Institute of Biochemistry and Molecular Biology School of Medicine Shandong University Jinan Shandong 250012 China Shandong Center for Disease Control and Prevention JinanShandong 250014 China QUANGANG PHARMACEUTICAL SD CO. LTD. JinanShandong 250014 China

Background Tumstatin is a novel endogenous angiogenesis inhibitor which is widely studied using purified *** current study evaluates the antiangiogenic effects of tumstatin-overexpression plasmid in vitro, reveals the mechanism underlying the vascular endothelial cell growth inhibition and searches for a novel method administering tumstatin *** The eukaryotic expression plasmid pcDNA-tumstatin encoding tumstatin gene was constructed and transfected to human umbilical vein endothelial cell ECV304 and human renal carcinoma cell *** of tumstatin in the two cell lines was determined by RT-PCR and Western *** endothelial cell proliferation was assessed by CCK-8 assay and cell cycle was analyzed by flow *** investigate the mechanism by which pcDNA-tumstatin inhibited vascular endothelial cell proliferation in vitro, cyclin D1 protein was detected by Western *** DNA sequence confirmed that pcDNA-tumstatin was successfully ***-PCR and Western blotting indicated that tumstatin could express in the two cell lines *** tumstatin gene transfer, ECV304 cell growth was significantly inhibited and the cell cycle was arrested in G1 *** Western blotting showed that pcDNA-tumstatin decreased the level of cyclin D1 *** Overexpression of tumstatin mediated by pcDNA 3.1 （＋） specially inhibited vascular endothelial cells by arresting vascular endothelial cell in G1 phase resulting from downregulation of cyclin D1 and administration of tumstatin using a gene therapy might be a novel strategy for cancer therapy.

关键词： tumstatin angiogeniesis gene therapy

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旅游资源非优区“依附式开发”论

旅游学刊 2005年第1期20卷 76-79页

作者：许春晓湖南师范大学旅游学院湖南长沙410081

旅游资源非优区的依附式开发是一种客观现象 ,存在着功能互补、时间补足和综合补足 3个类型。总结其开发机理 ,表现出资源优势互补为必要条件 ,合作与竞争融合为基本属性 ,功能差异为表现形式 ,等级—规模配比为基本规律 ,适者生存为基... 详细信息

旅游资源非优区的依附式开发是一种客观现象 ,存在着功能互补、时间补足和综合补足 3个类型。总结其开发机理 ,表现出资源优势互补为必要条件 ,合作与竞争融合为基本属性 ,功能差异为表现形式 ,等级—规模配比为基本规律 ,适者生存为基本归宿。本文以湖南省武冈市旅游业的依附式发展为案例。

关键词：旅游资源旅游开发旅游区

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国际政治中的道德困境

陕西师范大学学报（哲学社会科学版） 2006年第6期35卷 122-126页

作者：许晓春陕西师范大学政治经济学院陕西西安710062

关于国际政治中的道德问题,西方话语长期占据强势地位。现实主义从权力概念出发,或者持道德虚无态度,或者将道德置于权力的支配之下,为强权政治制造理论依据。而理想主义所宣扬的道德的“普世价值”则意在实现西方价值观的全球传播,其... 详细信息

关于国际政治中的道德问题,西方话语长期占据强势地位。现实主义从权力概念出发,或者持道德虚无态度,或者将道德置于权力的支配之下,为强权政治制造理论依据。而理想主义所宣扬的道德的“普世价值”则意在实现西方价值观的全球传播,其迷人的道德措辞往往成为强权国家干涉行动的借口。随着全球国际社会的日渐形成,道德因素在协调国际关系、维系国际社会的和谐与稳定方面的作用日益重要,但由于缺乏强制性和共同认可的理论支持,国际政治中的道德原则仍然是脆弱的,国际道德与国家利益间的矛盾仍是建构国际道德体系所面临的最大困难。

关键词：国际社会国际道德国际政治

中国红色旅游经典景区网络关注度时空演变及影响因素

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自然资源学报 2021年第7期36卷 1792-1810页

作者：唐鸿许春晓湖南师范大学旅游学院长沙410081 铜仁学院经济与管理学院铜仁554300

借助"百度指数",获取2011—2019年中国31个省(市、自治区)对红色旅游经典景区的网络关注度,结合区域差异分析法、景区偏好系数分析红色旅游经典景区网络关注度的时空演变特征,利用面板数据回归模型和地理探测器揭示其影响机理。研究发现... 详细信息

借助"百度指数",获取2011—2019年中国31个省(市、自治区)对红色旅游经典景区的网络关注度,结合区域差异分析法、景区偏好系数分析红色旅游经典景区网络关注度的时空演变特征,利用面板数据回归模型和地理探测器揭示其影响机理。研究发现:(1)从时序上看,2011—2019年红色旅游经典景区的网络关注度持续上升,具有明显的季节性差异,呈"M"型变化形态。(2)从区域上看,东—中—西部具有明显的梯度递减特征,区域差异呈东—西—中部依次递减态势,空间结构比较均衡,东部地区多位于热点区,中部地区多处于一般区,西部地区则属于冷点区,各省(市、自治区)存在一定季节性差异。(3)景区角度方面,景区的月际变化分为单峰型、双峰型和多峰型三种,单峰型季节差异显著,双峰型和多峰型的季节差异较小,景区偏好类型呈"金字塔"结构,具有"多中心"分布特征,整体格局相对稳定。(4)影响因素方面,客源地网络发展水平的贡献>人口规模>教育水平>经济发展水平,而旅游恩格尔系数的影响不显著,目的地的星级酒店数量、旅游化水平、市外交通可达性是重要影响因素,信息化水平、空气质量、旅行社及公共管理能力是主要影响因素,其他因素影响力较小。

关键词：红色旅游经典景区网络关注度时空演变影响因素

Study of cochlear hydrops analysis masking procedure in patients with Meniere＇s disease and otologically normal adults

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Chinese Medical Journal 2012年第24期125卷 4449-4453页

作者： SHANG Ying-ying DIAO Wen-wen NI Dao-feng GAO Zhi-qiang xu chun-xiao LI Feng-rong Department of Otorhinolaryngology Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100730 China

Background The cochlear hydrops analysis masking procedure （CHAMP） is a new diagnostic technique for Meniere＇s disease （MD）. But its value has not been well proven. This study aimed to evaluate the diagnostic value of CHAMP for MD. Methods CHAMP test was taken in three populations using the Auditory Evoked Potential system delivered by Bio-logic Systems Corporation：（1） otologically normal subjects; （2） patients clinically diagnosed with definite MD; （3） patients clinically diagnosed with probable and possible MD. Results According to the comparison between the normal and definite MD group, if the abnormal criterion of CHAMP was defined as latency delay less than 0.3 ms, then the corresponding sensitivity was only 52%. However, if the abnormal criterion was defined as latency delay between 0.6 and 3.8 ms, then a sensitivity of 93% and a specificity of 100% can be achieved. The complex amplitude ratio showed a significant overlap between normal and definite MD group. If the abnormal criterion was defined as a complex amplitude ratio less than 0.95, the corresponding specificity was only 50%. However, if the abnormal cdtedon was defined as less than 0.80, the corresponding sensitivity was 60%, and the specificity was 97%. If the abnormal criterion of CHAMP was defined as latency delay less than 0.6 ms or the complex amplitude ratio less than 0.80, CHAMP result can be obtained in all subjects with good sensitivity and specificity. Conclusions CHAMP can differentiate patients with Meniere＇s disease from otologically normal subjects with high sensitivity and specificity. The recommended cdterion of abnormal CHAMP was a latency delay less than 0.6 ms or a complex amplitude ratio less than 0.80.

关键词： auditory evoked potentials diagnostic techniques Meniere's disease