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Resistin might not be a risk factor for carotid artery atherosclerosis in elderly Chinese males

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Journal of Geriatric Cardiology 2014年第3期11卷 222-228页

作者： Hao WANG Yu-Tang WANG Li FAN Yu-tao GUO Yang shi tao tao yue-Xiang ZHAO First Geriatric Cardiology Division Chinese PLA General Hospital 28 Fuxing Rd. Beijing 100853 China

Objective To investigate the correlation between the serum resistin level and carotid artery atherosclerosis in elderly Chinese males. Methods The study enrolled 235 elderly Chinese males [median age 76 （range 60-97） years] scheduled for ultrasound examination of carotid artery plaque and determination of carotid artery intima-media thickness （CIMT）. They were divided into carotid atherosclerotic plaque （CAP） and carotid atherosclerotic plaque-free （CAP-free） groups according to the ultrasound results. Their clinical profiles were col-lected, and the serum resistin and other blood biochemistry levels were *** The CAP group was older and had a thicker mean CIMT than the CAP-free group. However, there was no difference in the serum resistin level between the groups. CIMT was positively correlated with age （r = 0.299,P〈 0.001）. The serum resistin level was not correlated with CIMT, even after controlling for age. Multiple linear regression analysis revealed that age （β = 0.001,P〈 0.001） and body mass index （β = 0.002,P= 0.015） were significantly and posi-tively correlated with the mean CIMT. Only age [odds ratio （OR）： 1.159; 95% confidence interval （CI）： 1.078-1.183,P〈 0.001] was associ-ated with the presence of carotid artery atherosclerotic plaque. The serum resistin level was not correlated with the mean CIMT or associated with the presence of carotid artery atherosclerotic *** The results suggest that resistin might not be a risk factor for atherosclerosis in elderly Chinese males.

关键词： Resistin Intima-media thickness Atherosclerosis The elderly

THREE-DIMENSIONAL REGULARITIES OF DISTRIBUTION OF AIR-INLET CHARACTERISTIC VELOCITY IN NATURAL-DRAFT WET COOLING TOWER

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Journal of Hydrodynamics 2008年第3期20卷 323-330页

作者： WANG Kai SUN Feng-zhong ZHAO Yuan-bin GAO Ming shi yue-tao School of Energy and Power Engineering Shandong University Jinan 250061 China

A model for heat and mass transfer in a natural-draft wet cooling tower was established. Numerical simulation with the κ-ε turbulent model was conducted. Distribution rules of air inlet aerodynamic field were studied. Field experiments were done in a cooling tower in power plant, and the test data was compared with the related results. The definition of characteristic air velocity was proposed and its influencing factors, such as the cross-wind velocity and circumferential angle, were quantitatively studied. It can be used to evaluate the performance of cooling tower and to calculate the ventilation quantity and resistance of air inlet. It is also a theoretical basis for cooling tower design and performance optimization.

关键词： cooling tower flow field numerical simulation air inlet

NUMERICAL SIMULATION OF FLOW FIELDS IN A NATURAL DRAFT WET-COOLING TOWER

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Journal of Hydrodynamics 2007年第6期19卷 762-768页

作者： YANG Xiang-liang SUN Feng-zhong WANG Kai shi yue-tao WANG Nai-hua Heze Power Plant China Guodian Coporation Heze 274000 China School of Power and Energy Engineering Shandong University Jinan 250061 China

The flow field in the hyperbolic natural draft wet-cooling tower, which has great effects on the economy and security of power plant, was studied through numerical simulation. The mathematical model was established and analyzed in order to optimize the cooling-tower and to evaluate its efficiency. Various working conditions were considered and compared with each other, such as the circulating water flux, air temperature and tower resistance. It is concluded that when the cooling-tower runs without wind, there is a vacuum region inside the tower and the pressure rises with the increase of the tower height. Meanwhile, the inner flow field is axisymmetrical. The air velocity achieves its climax at the axis. It is also found that the effect of circulating water temperature is equivalent to that of the water flux.

关键词： cooling tower flow field circulation water flux circulation water temperature numerical simulation

EXPERIMENTAL STUDY ON ENHANCED HEAT TRANSFER WITH NI-BASED IMPLANTED SPIRAL FINNED TUBES

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Journal of Hydrodynamics 2003年第5期15卷 65-69页

作者： Sun Feng zhong, Huang Xin yuan, Wang Nai hua, shi yue tao, Ping Ya ming School of Energy and Power Engineering, Shandong University, Jinan 250061, China Sch. of Energy and Power Eng. Shandong Univ. Ji'nan 250061 China

The new type of heat exchanger elements-Ni-based Implanted Spiral FinnedTurbes (NISFT) was studied and tested, which can contribute to increase the efficiency andreliability. The relation of Nu, Eu and Re with different fin pitch, fin height, transverse pitchand longitudinal pitch were gained, which constituted the basic foundation for the engineeringapplication of NISFT.

关键词： enhanced heat transfer heat exchanger finned tube

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螺旋翅片管防磨和防积灰特性的试验研究

动力工程 2006年第1期26卷 145-148页

作者：史月涛韩志航孙奉仲陶文铨西安交通大学能源与动力工程学院西安710049 山东大学能源与动力工程学院济南250061

应用三维颗粒动态分析仪(PDA)对气固两相流绕流螺旋翅片管进行了防磨和防积灰的实验研究。实验结果表明在翅片之间,固相颗粒密度和主流速度呈抛物线规律分布。颗粒密度和速度的这种分布规律降低了固体颗粒对翅片壁面的撞击能量,从而减... 详细信息

应用三维颗粒动态分析仪(PDA)对气固两相流绕流螺旋翅片管进行了防磨和防积灰的实验研究。实验结果表明在翅片之间,固相颗粒密度和主流速度呈抛物线规律分布。颗粒密度和速度的这种分布规律降低了固体颗粒对翅片壁面的撞击能量,从而减轻了翅片和基管的磨损。随着来流速度和来流密度的提高,迎风面区域磨损加剧,其他区域基本不受影响。实验数据还表明,螺旋翅片的导流作用使得迎风面的滞点处产生一个轴向速度,这和光管有着本质的区别。此速度的存在有利于减轻积灰。

关键词：工程热物理锅炉螺旋翅片管磨损积灰

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真空状态下等离子注入铜管管束的换热特性

动力工程 2006年第4期26卷 531-534页

作者：高明孙奉仲史月涛王乃华平亚明山东大学能源与动力工程学院济南250061

进行了不同真空度下单管的凝结试验,研究了真空状态下等离子注入铜管管束的换热特性,以及其换热系数随Re数的变化情况,并与普通铜管管束的换热性能进行比较。研究表明:两种管束的凝结换热系数和总换热系数都随着真空度的提高而增大,而... 详细信息

进行了不同真空度下单管的凝结试验,研究了真空状态下等离子注入铜管管束的换热特性,以及其换热系数随Re数的变化情况,并与普通铜管管束的换热性能进行比较。研究表明:两种管束的凝结换热系数和总换热系数都随着真空度的提高而增大,而且真空状态下等离子注入铜管表面较普通铜管有更好的换热性能。在较高真空度(0.05 MPa)和较大Re数(34755)下,等离子管束的总换热系数约为普通铜管管束的1.43倍,凝结换热系数约为普通铜管管束的2倍。

关键词：工程热物理凝汽器离子注入管束传热特性真空度珠状凝结

基于现场数据确定凝汽器真空偏低治理方案的判据及分析

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汽轮机技术 2006年第3期48卷 190-192页

作者：王伟孙奉仲王凯史月涛山东大学能源与动力工程学院济南250061

凝汽器真空偏低一直是电厂机组运行中人们普遍关注的问题。为了使凝汽器真空降低得到显著的治理效果,分析了影响凝汽器真空的各因素及计算公式,得出了不同因素影响率间的相对关系。在此基础上,提出以Δt/δt作为凝汽器真空偏低治理方案... 详细信息

凝汽器真空偏低一直是电厂机组运行中人们普遍关注的问题。为了使凝汽器真空降低得到显著的治理效果,分析了影响凝汽器真空的各因素及计算公式,得出了不同因素影响率间的相对关系。在此基础上,提出以Δt/δt作为凝汽器真空偏低治理方案的判据。根据某600MW机组真空降低时的运行数据,利用上述判据确定了解决该机组真空偏低的方案,并给出了相应的措施。实践证明利用该判据确定的治理方案可使凝汽器真空得到显著提高。

关键词：凝汽器真空偏低治理方案运行数据判据