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Validation of MODIS aerosol products by CSHNET over China

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Chinese Science Bulletin 2007年第12期52卷 1708-1718页

作者： WANG LiLi XIN JinYuan WANG YueSi LI ZhanQing WANG PuCai liu guangren WEN TianXue Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Department of Meteorology University of Maryland College Park MD 20782 USA

The Chinese Sun Hazemeter Network (CSHNET) provides the necessary ground-based observation to validate and assess the applicability of MODIS aerosol optical depth (AOD) products over different ecological and geographic regions in China for the first time. The validation results show that the comprehensive utilization ratio and applicability of MODIS products varied very much over different regions and seasons from August 2004 to July 2005. On the Tibetan Plateau, the comprehensive utili- zation ratio of MODIS data was low: MODIS products only accounted for 16% of the ground-based observation; on average, 31% to 45% of MODIS products fell within the retrieval errors issued by NASA. A similar result was found in northern desert areas with the ratio of MODIS to observation ranging from 15% to 55%, with 7% to 39% of MODIS products within errors. In the remote northeast corner of China, low ratios of MODIS to observation were also found ranging from 14% to 46%, with 49% to 69% of MODIS within errors. The forested sites exhibited moderate ratios of MODIS to observation ranging from 46% to 65%, with 30% to 59% of MODIS within errors. This was similar to numbers observed at sites along eastern seashore of China and inland urban sites with the ratio of MODIS to observation between 63% to 75%, with 25% to 67% of MODIS within errors for sites along eastern seashore of China and 43% to 78%, with 35% to 75% of MODIS within errors for inland urban sites. The ratio of MODIS to observation over agricultural areas ranged from 61% to 89%; 59%-88% of MODIS fell within the retrieval errors. At homogeneous and well vegetated areas, the comprehensive utilization ratio of MODIS products was over 80% and above 70% of MODIS products fell within the retrieval errors in growing season.

关键词：中国地区太阳分光观测网气溶胶光学厚度中分辨率成像光谱辐射计大气科学

Fluxes of CH4 and N_2O from soil under a tropical seasonal rain forest in Xishuangbanna, Southwest China

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Journal of Environmental Sciences 2008年第2期20卷 207-215页

作者： YAN Yuping SHA Liqing CAO Min ZHENG Zheng TANG Jianwei WANG Yinghong ZHANG Yiping WANG Rui liu guangren WANG Yuesi SUN Yang Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Kunming 650223 China Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduated School of the Chinese Academy of Sciences Beijing 100049 China

CH4 and N2O fluxes from soil under a tropical seasonal rain forest in Xishuangbanna, Southwest China were measured for one year using closed static chamber technique and gas chromatography method. Three treatments were set in the studied field：（A） litter-free, （B） with litter, and （C） with litter and seedling. The results showed that the soil in our study was a sink of atmospheric CH4 and source of atmospheric N2O. The observed mean CH4 fluxes from treatments A, B, and C were -50.0 ± 4.0, -35.9 ± 2.8, -31.6 ± 2.8 μgC/（m^2·h）, respectively, and calculated annual fluxes in 2003 were -4.1, -3.1, and -2.9 kgC/hm^2, respectively. The observed mean N2O fluxes from treatments A, B, and C were 30.9 ± 3.1, 28.2 ± 3.5, 50.2±3.7 μgN/（m^2·h）, respectively, and calculated annual fluxes in 2003 were 2.8, 2.6, and 3.7 kgN/hm^2, respectively. Seasonal variations in CH4 and N2O fluxes were significant among all the three treatments. The presence of litter decreased CH4 uptake during wet season （P 〈 0.05）, but not during dry season. There was a similar increase in seedlings-mediated N2O emissions during wet and dry seasons, indicating that seedlings increased N2O emission in both seasons. A strong positive relationship existed between CH4 fluxes and soil moisture for all the three treatments, and weak relationship between CH4 fluxes and soil temperature for treatment B and treatment C. The N2O fluxes correlated with soil temperature for all the three treatments.

关键词： global warming greenhouse gases rain forest seasonal variability soil moisture soil temperature

Long-Term Trends in Photosynthetically Active Radiation in Beijing

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Advances in Atmospheric Sciences 2010年第6期27卷 1380-1388页

作者：胡波王跃思刘广仁 State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of Sciences

A long-term dataset of photosynthetically active radiation （Qp） is reconstructed from a broadband global solar radiation （Rs） dataset through an all-weather reconstruction model. This method is based on four years＇ worth of data collected in Beijing. Observation data of Rs and Qp from 2005-2008 are used to investigate the temporal variability of Qp and its dependence on the clearness index and solar zenith angle. A simple and effcient all-weather empirically derived reconstruction model is proposed to reconstruct Qp from Rs. This reconstruction method is found to estimate instantaneous Qp with high accuracy. The annual mean of the daily values of Qp during the period 1958-2005 period is 25.06 mol m-2 d-1. The magnitude of the long-term trend for the annual averaged Qp is presented （-0.19 mol m-2 yr-1 from 1958-1997 and -0.12 mol m-2 yr-1 from 1958-2005）. The trend in Qp exhibits sharp decreases in the spring and summer and more gentle decreases in the autumn and winter.

关键词： photosynthetically active radiation historical data reconstruction long-term trends

Variability and reduction of atmospheric pollutants in Beijing and its surrounding area during the Beijing 2008 Olympic Games

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Chinese Science Bulletin 2010年第18期55卷 1937-1944页

作者： XIN JinYuan WANG YueSi TANG GuiQian WANG LiLi SUN Yang WANG YingHong HU Bo SONG Tao JI DongSheng WANG WeiFeng LI Liang liu guangren State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy ofSciences Beijing 100029 China

The Beijing-Tianjin-Hebei Atmospheric Environment Monitoring Network was established by the Institute of Atmospheric Physics,Chinese Academy of *** goals of the network were to monitor and provide warnings of the atmospheric quality in Beijing and its surrounding area during the Beijing 2008 Olympic *** results showed that the atmospheric complex pollution exhibited high concentrations of ozone and fine particles and oxidation in summer,with a ubiquitous regional *** regional mean concentrations of SO2,PM2.5,NO2,and O3_8h max(the maximum daily 8 h mean) and Ox were 22±11,90±40,25±5,136±35 and 112±21 μg/m3 in summer,*** the Olympic Games,the mean concentration of SO2,PM2.5,NO2,O3_8h max,and Ox were 12.5±4,56±28,23±4,114±29,95±17 μg/m3 in the region,respectively,and fell by 51.0%,43.7%,13%,20.2%,and 18.9%,respectively,compared to the prophase mean before the Olympic *** concentration of atmospheric pollutants declined significantly and achieved the "Green Olympics" control goal of air *** the Olympic Games,SO2,PM2.5 and NOx increased significantly as the temporary atmospheric pollution control measures were terminated.

关键词：北京2008年奥运会大气污染物周边地区 2008年北京奥运会环境监测网络 PM2.5 平均浓度二氧化硫

Trend,seasonal and diurnal variations of atmospheric CO_2 in Beijing

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Chinese Science Bulletin 2002年第24期47卷 2050-2055页

作者： WANG Yuesi, WANG Changke, GUO Xueqing, liu guangren & HUANG YaoLAPC, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100083, China Department of Chemistry, Capital Normal University, Beijing 100037, China LAPC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Department of Chemistry Capital Normal University Beijing China

The concentration of atmospheric CO2 in Beijing increased rapidly at a mean growth rate of 3.7%·a-1 from 1993 to 1995. After displaying a peak of (409.7±25.9) μmol·mol-1 in 1995, it decreased slowly. Both the almost stable anthropogenic CO2 source and increasing biotic CO2 sink contribute to the drop of CO2 concentration from 1995 to 2000. The seasonal variation of CO2 concentration exhibits a clear cycle with a maximum in winter, averaging (426.8± 20.6)μmol·mol-1, and a minimum in summer, averaging (369.1±6.1)μmol·mol-1. The seasonal variation of CO2 concentration is mainly controlled by phenology. The mean diurnal variation of atmospheric CO2 concentration for a year in Beijing is highly clear: daily maximum CO2 concentration usually occurs at night, but daily minimum CO2 concentration does in the daytime, with a mean diurnal difference more than 34.7μmol·mol-1. It has been revealed that the interannual variations of atmospheric CO2 concentration in winter and autumn regulated the

关键词： atmospheric CO2 annual variation seasonal variation diurnal variation urban environment.

国产紫外总日射表性能测试(Ⅱ):室外测试及与国外同类产品比较

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太阳能学报 2005年第3期26卷 313-320页

作者：汤洁王炳忠刘广仁中国气象科学研究院北京100081 中国科学院大气物理所北京100085

介绍了几种国产紫外总日射表与美国YankeeUVB-1型紫外总日射表和EppleyTUVR型紫外总日射表在室外进行半年对比试验的结果。发现:在几种国产紫外总日射表中,从性能上讲,无论是与TUVR型的相关性,还是余弦响应,均以UVB-2型总日射表为佳,另... 详细信息

介绍了几种国产紫外总日射表与美国YankeeUVB-1型紫外总日射表和EppleyTUVR型紫外总日射表在室外进行半年对比试验的结果。发现:在几种国产紫外总日射表中,从性能上讲,无论是与TUVR型的相关性,还是余弦响应,均以UVB-2型总日射表为佳,另外,该总日射表还具有自动恒温装置,从而可免受环境温度的干扰;原计划在对比中以YankeeUVB-1型紫外总日射表作为UVB波段总日射表的相对标准,通过试验发现,它与任何一种紫外总日射表之间的关系均呈非线性。通过对其余弦响应实际测量发现,由于该紫外总日射表并无余弦修正装置,余弦响应不良也就不足为奇了。YankeeUVB-1型总日射表虽与EppleyTUVR型总日射表在测量波段上并不一致,但通过理论计算发现,在太阳高度较高时(>40°),二者之间还是存在着较好的线性关系。可以借此判断仪器性能之优劣。

关键词： UVB辐射紫外总日射表

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光合光量子传感器校准的一些问题

太阳能学报 2008年第1期29卷 1-5页

作者：王炳忠胡波刘广仁中国气象科学研究院北京100081 中国科学院大气物理研究所北京100081

介绍了光合光量子传感器的校准方法,只要有符合国家标准的辐照度标准灯,并用标准灯对适当级别的光谱辐射计进行校准后,就可在日光下供此类仪器定期校准之用。并证明了所介绍方法的实际可行性。由于LI- COR公司随LI-190型仪器发放的使用... 详细信息

介绍了光合光量子传感器的校准方法,只要有符合国家标准的辐照度标准灯,并用标准灯对适当级别的光谱辐射计进行校准后,就可在日光下供此类仪器定期校准之用。并证明了所介绍方法的实际可行性。由于LI- COR公司随LI-190型仪器发放的使用说明书中有关量子传感器的光谱响应曲线图前后不相一致,且未加说明.文中对此进行了重点论证和讨论。当前并不存在真正意义上的光量子传感器,实际所用的也只有能量传感器.以光量子单位表示的测量结果是经公式计算得出的。此外,还证明了量子单位测量结果与能量单位测量结果关系的一致性.如有需要,在校准时就可同时得出量子的和能量的两种灵敏度,从而免除了由于单位互换带来的误差。

关键词：光合有效辐射光量子传感器校准

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复合地层纵向曲线顶管施工技术

地质科技情报 2016年第2期35卷 67-70页

作者：刘广仁常喜平王乐中国石油天然气管道局第四工程分公司河北廊坊065000

采用顶管法穿越江河一般均选择地质条件较好、水压较低的直线顶进方式施工,针对大坡度纵向曲线顶管穿江施工国内目前还没有先例。富春江顶管隧道全长658.05m,施工水压高、坡度大、穿越地层复杂。通过采用具有破岩能力的泥水加压平衡顶... 详细信息

采用顶管法穿越江河一般均选择地质条件较好、水压较低的直线顶进方式施工,针对大坡度纵向曲线顶管穿江施工国内目前还没有先例。富春江顶管隧道全长658.05m,施工水压高、坡度大、穿越地层复杂。通过采用具有破岩能力的泥水加压平衡顶管设备、配置有特殊密封的大行程组合式中继间、润滑效果良好的自动润滑注浆系统和可进行大落差曲线隧道测量的陀螺导向系统等相关技术实现了复合地层"V"字型纵向曲线穿江顶管隧道的贯通。该项目的顺利实施为我国在复杂条件下的顶管施工开拓了新的设计理念并积累了相关施工参数和经验。

关键词：纵向曲线复合地层大坡度穿江顶管

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两种提取系统对牙齿DNA检验效果比较

中国法医学杂志 2018年第5期33卷 516-517,515页

作者：刘光仁山东省寿光市公安局物证鉴定中心山东寿光262700

目的通过本次实验对比两种常用的DNA自动化提取系统对牙齿DNA纯化的效果。方法采用博坤微量生物物证DNA自动化提取系统(整合版)和Automate Express BTA自动化法医DNA提取系统分别对同一人的牙齿进行检验。结果经博坤微量生物物证DNA自... 详细信息

目的通过本次实验对比两种常用的DNA自动化提取系统对牙齿DNA纯化的效果。方法采用博坤微量生物物证DNA自动化提取系统(整合版)和Automate Express BTA自动化法医DNA提取系统分别对同一人的牙齿进行检验。结果经博坤微量生物物证DNA自动化提取系统(整合版)检验的牙齿DNA图谱峰高平均值约为Automate Express BTA自动化法医DNA提取系统的2倍;等位基因个数平均值约为1.5倍。结论博坤微量生物物证DNA自动化提取系统(整合版)代替传统手工提取方法检验牙齿,相较于Automate Express BTA自动化法医DNA提取系统提取效果更好,能满足实际检案的要求,可在法医学实践中选择使用。

关键词：法医物证学 STR分型自动化法医DNA提取系统牙齿