ELNio事件与我国月降水和温度的关系

用对比度分析方法,研究了ELNino事件对我国月降水和温度的影响,并进行了信度检验.结果表明:ELNino年,全国降水1～9月偏少,10～12月偏多.当5月降水异常少时,ELNino发生的概率达50%以上.当4月温度异常高时,ELNino发生的概率为零,而4月气温异常低时,ELNino发生的概率达50%～83%.这对ELNino的预测,提出了一个重要的信号依据.     

珠江三角洲地区边界层气象特征研究

根据珠江三角洲地区9个气象台站1995-2000年地面气象资料和部分地区的探空资料,分析研究区域气候与天气背景,风、温、混合层厚度、大气稳定度等大气边界层特征.结果表明:珠江三角洲地区受季风影响显著,还受海陆风、城市热岛环流、越南岭下沉气流等的复合影响;逆温频率很高,混合层高度较低,大气层结比较稳定;复杂的下垫面对珠江三角洲地区大气边界层有重要影响.     

Accurate prediction of the critical heat flux for pool boiling on the heater substrate

While the influence of liquid qualities, surface morphology, and operating circumstances on critical heat flux (CHF) in pool boiling has been extensively studied, the effect of the heater substrate has not. Based on the force balance analysis, a theoretical model has been developed to accurately predict the CHF in pool boiling on a heater substrate. An analytical expression for the CHF of a heater substrate is obtained in terms of the surface thermophysical property. It is indicated that the ratio of thermal conductivity (k) to the product of density (ρ) and specific heat (c_p) is an essential substrate property that influences the CHF. By modifying the well-known force-balance-based CHF model (Kandlikar model), the thermal characteristics of the substrate are taken into consideration. The bias of predicted CHF values are within 5% compared with the experimental results.     

秋季珠江口地区海风对城市群空气污染的影响

 根据2004年10月珠江三角洲大气边界层和空气污染物观测资料,分析了位于城市群下风向的珠江口地区的海风对珠江三角洲城市群空气污染的影响。结果表明,秋季珠江口地区海风将抑制城市群空气污染物向下风向输送,而导致城市群空气污染物在向下风向“迁移”过程中“减速”或在城市群短期“堆积”,使城市群空气污染物浓度随海风的出现显著上升,珠江口地区出现海风日城市群空气污染物日平均和日最高浓度与非海风日相比上升了2到4倍;而珠江口地区空气污染物浓度随海风的出现而降低。     

惠州市夏秋季臭氧污染特征和典型污染过程

利用广东省惠州市2013-2016年逐日和逐时的大气环境和气象观测资料,统计分析了惠州市夏秋季臭氧污染天气特征并分析了2013年7月12-13日臭氧污染过程。结果表明:(1)惠州市臭氧污染在一年四季均有出现,夏秋季(7-10月)年平均出现日数为12. 5d占年臭氧污染日的73. 5%,夏秋季臭氧污染日和臭氧中度污染日偏西风(WSW-W-WNW-NW)出现频率合计分别为44. 9%和74. 4%;气象条件分析表明惠州市夏秋季臭氧污染日大多出现在天气晴朗、日照充足、气温较高且为偏西风的天气下,夏秋季的天气气候特征使其成为臭氧污染的高发时段。(2)分析2013年7月12-13日惠州市臭氧中度污染过程发现,此次臭氧污染过程主要是受"苏力"外围下沉和偏西气流的共同影响,天气晴朗、日照充足、天气炎热非常有利于臭氧生成,地面和低空吹偏西风使惠州市处于珠三角城市群的下风向存在区域污染输送,同时垂直方向的下沉气流不利于污染物输送与扩散。     

An overview of thermoelectric films:Fabrication techniques,classification,and regulation methods

Thermoelectric materials have aroused widespread concern due to their unique ability to directly convert heat to electricity without any moving parts or noxious emissions.Taking advantages of two-dimensional structures of thermoelectric films,the potential applications of thermoelectric materials are diversified,particularly in microdevices.Well-controlled nanostructures in thermoelectric films are effective to optimize the electrical and thermal transport,which can significantly improve the performance of thermoelectric materials.In this paper,various physical and chemical approaches to fabricate thermoelectric films,including inorganic,organic,and inorganic–organic composites,are summarized,where more attentions are paid on the inorganic thermoelectric films for their excellent thermoelectric responses.Additionally,strategies for enhancing the performance of thermoelectric films are also discussed.     

2004年10月珠江口西岸海陆风特征观测研究

根据2004年10月在珠江口西岸新垦观测的大气边界层探测资料和自动气象站资料,研究了珠江口西岸海陆风特征。结果表明:珠江口西岸海风出现频率较高,20时出现频率为51.8%;海风出现和结束时间都较晚,一般在14-18时之间出现,23时-次日02时之间结束;海风环流高度随海风持续时间逐步升高,23时最高达到700 m左右;海风使珠江口西岸贴地逆温出现时间推迟,低空逆温出现频率增加。