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Numerical study of aerosol effect on three types of clouds and precipitation in Beijing area

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Research in Cold and Arid Regions 2012年第4期4卷 342-350页

作者： ZhiGuo Yue XiaoDong Liu ShuYan Liu SKLLQG Institute of Earth EnvironmentChinese Academy of SciencesXi'anShaanxi 710075China weather modification office of Shaanxi province Xi'anShaanxi 710015China Earth System Science and Interdisciplinary Center University of MarylandCollege ParkMaryland 20740USA

Three types of rainfall （storm, moderate and slight rainfall） in the Beijing area were simulated by the weather Research and Fore- cast （WRF3.2） model coupled with Milbrandt-two-moment cloud microphysics scheme, to explore the effect of aerosols on clouds and precipitation under continental and maritime aerosol scenarios. Results indicate that an increase of aerosols has various effects on clouds and precipitation. （1） The amount of surface precipitation is obviously affected. With an increase of aerosol con- centration, the 48-hr total precipitation of storm and moderate rainfall decreased by 23% and 16.6%, respectively, and the 24-hr total precipitation of slight rainfall decreased by 14.0%. （2） The distribution of surface precipitation is also clearly affected. The average precipitation for a rain storm increases in most parts of western Beijing and decreases by more than 20 mm in most parts of eastern Beijing with increasing aerosol concentration. The average precipitation of moderate rainfall decreases by 0.1-5 mm in most parts of the Beijing area. The effect of increased aerosol concentration is weak for slight rainfall distribution in the study area. （3） With an increase of aerosol concentration, a narrower width and lower precipitation peak value are found in the storm rainfall, and its duration is prolonged for the high aerosol concentration. An earlier precipitation termination of moderate rainfall is found with increasing aerosol concentration. （4） The upper-air hydrometeors vary with aerosol concentration, For storm and moderate rainfall, significantly higher cloud water concentration and lower rain water were found under the continental aerosol scenario.

关键词： aerosol Beijing area clouds and precipitation indirect effect numerical simulation

An investigation on the dosimetric impact of hip prosthesis in radiotherapy

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Nuclear Science and Techniques 2016年第1期27卷 29-36页

作者： Wen-Cheng Shao Yan-Ling Bai Wen-Bo Zhao Pu-Nan Sun Feng-Li Liu Department of Radiation Physics Harbin Medical University Cancer Hospital Beijing Xiao Qing Environmental Engineering Co. LtdHarbin office School of physical science and technology Heilongjiang University

The objectives of this study are to evaluate the dosimetric impact of hip prosthesis using ELEKTA linac X-rays and compare the dose perturbations of metallic and nonmetallic hip prostheses. The local dose distributions of typical hip prostheses were calculated for 4, 8, and 15 MV beams by Geant4. Three prosthesis materials were selected in calculation to reveal the relation between material type and local dose perturbations of prostheses. Furthermore,the effect of nominal energy on prosthesis perturbation was also discussed and analyzed. Taking the calculated dose to the hip joint as reference, considerable differences were observed between prostheses and hip joints. In the prosthesis shadow region, the relative dose decreasing was up to 36, 21, and 16 % for the Co–Cr–Mo alloy, titanium alloy, and ceramic prostheses, respectively. In backscattering region, the relative dose increasing was about1–7 %. Overall, the results show that the dose perturbation effect of prostheses was mainly determined by material type, nominal energy, and density. Among these typical hip prostheses, ceramic prosthesis introduces the lowest dose perturbations.

关键词：髋关节剂量学假体放射治疗扰动效应 Geant4 X射线剂量直线加速器

Application of New Type of Detection Data in a Heavy Rainfall Process in Changsha

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Meteorological and Environmental Research 2019年第4期10卷 37-38,41页

作者： Huo Tao Shan Nan Tang Xiaonan Fan Yu Liu Daxin Changsha Meteorological Bureau Changsha 410205 China Changsha Comprehensive Meteorological Observation and Experiment Base of CMA Changsha 410205 China weather modification office in Liaoning province Shenyang 110016 China Meteorological Observation Center of CMA Beijing 100081 China

Using detection data with high space-time resolution from the wind profile radar and millimeter wave cloud radar of Changsha station, and combining observation data of ground automatic station, heavy precipitation process in Changsha area from June 29 to July 1, 2017 was analyzed. The results showed that the atmospheric temperature advection was calculated by inversion of wind profile radar data of boundary layer, and it could intuitively analyze changes of atmospheric temperature advection before and after precipitation process. The variation characteristics of intensity, thickness and height of warm and cold advection in the upper and lower levels were highly related to the evolution of the precipitation process. The millimeter wave cloud radar can better reflect the vertical structure and evolution of the cloud over the observatory, and had certain indications for the structure characteristics of cloud before the starting of precipitation. When the strong reflectivity started to approach the ground, it also meant that heavy precipitation began to appear.

关键词： Wind profile radar Millimeter wave cloud radar Temperature advection

Effect of farmland expansion on drought over the past century in Songnen Plain,Northeast China

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Journal of Geographical Sciences 2020年第3期30卷 439-454页

作者： YU Wanhui ZHANG Lijuan ZHANG Hongwen JIANG Lanqi ZHANG Ankang Pan Tao Key Laboratory of Remote Sensing Monitoring of Geographic Environment College of Heilongjiang ProvinceHarbin Normal UniversityHarbin 150025China Key Laboratory of Land Surface Process and Climate Change in Northwest Institute of Eco-Environment and Resources CASLanzhou 730000China heilongjiang province Institute of Meteorological Sciences Innovation and Opening Laboratory of Regional Eco-Meteorology in NortheastChina Meteorological AdministrationHarbin 150030China

The effects of human activities on climate change are a significant area of research in the field of global environmental *** use and land cover change(LUCC)has a greater effect on climate than greenhouse gases,and the effect of farmland expansion on regional drought is particularly *** the 1910s to the 2010s,cultivated land in Songnen Plain increased by 2.67 times,the area of cultivated land increased from 4.92×10^4 km^2 to 13.14×10^4 km^2,and its percentage of all land increased from 25%to 70%.This provides an opportunity to study the effects of the conversion of natural grassland to farmland on *** this study,the drought indices in Songnen Plain were evaluated from the 1910s to the 2010s,and the effect of farmland expansion on drought was investigated using statistical methods and the weather Research and Forecasting Model based on UK’s Climatic Research Unit *** resulting dryness index,Palmer drought severity index,and standardized precipitation index values indicated a significant drying trend in the study area from 1981 to *** trend can be attributed to increases in maximum temperature and diurnal temperature range,which increased the degree of *** on statistical analysis and simulation,the maximum temperature,diurnal temperature range,and sensible heat flux increased during the growing season in Songnen Plain over the past 100 years,while the minimum temperature and latent heat flux *** findings indicate that farmland expansion caused a drying trend in Songnen Plain during the study period.

关键词： drought effect farmland expansion centennial-scale changes Songnen Plain

Microbial fermentation of blue honeysuckle(Lonicera caerulea L.) polyphenol promotes insulin secretion and intervenes in obesity by promoting short-chain fatty acids production

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Food Science and Human Wellness 2023年

作者： Fangyi Pei Xinbo Cao Yanxin Ren Liangyang Mao Yueyi Liu Jingping Ge Wenxiang Ping Hebei University of Environmental Engineering， Hebei Key Laboratory of Agroecological Safety heilongjiang Provincial Key Laboratory of Plant Genetic Engineering and Biological Fermentation Engineering for Cold Region & Key Laboratory of Microbiology， College of heilongjiang province， heilongjiang University office of Academic Research， Qiqihar Medical University Engineering Research Center of Agricultural Microbiology Technology， Ministry of Education & heilongjiang Provincial Key Laboratory of Ecological Restoration and Resource Utilization for Cold Region & School of Life Sciences， heilongjiang University

During obesity treatment， clinicians have been burdened by the ever-increasing number of patients and the side effects of drug treatment. Finding new plant-derived active ingredients as an intervention for obesity has become a research focus. In this study， Plackett–Burman and Central Composite Design experiments， plant-wide target metabolomics technology， simulated human colon fermentation test， and cell experiment in vitro were successively used to investigate the effects of fermented and unfermented polyphenols (FP and UP， respectively) of blue honeysuckle on obesity. After the optimization of the response surface method， polyphenol content (1878.08 ±14.53) mg/100 g increased by 2.63 times after Lactobacillus rhamnosus 6224 and Saccharomyces cerevisiae W5 mixed fermentation. Twenty-three significantly different metabolites were observed in FP and UP. Of them， 7 different metabolites were significantly and positively correlated with short-chain fatty acids (SCFAs)， whereas negatively correlated with lipopolysaccharides (LPS). The contents of these 7 metabolites were significantly increased in FP. Furthermore， the effects of FP and UP on the SCFA biosynthesis pathway were different. Cell experiments revealed that polyphenols can significantly promote the secretion of gastrointestinal endogenous hormones and insulin and inhibit interleukin-6 levels. Linear regression analysis revealed SCFAs had a positive regulatory effect on glycolipid metabolism， whereas LPS had a negative effect. Overall， these crucial findings provide an economical and simple method for obtaining blue honeysuckle polyphenols and laying a theoretical foundation for its application in the therapeutic intervention against obesity.

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Effects of transport on aerosols over the eastern slope of the Tibetan Plateau:synergistic contribution of Southeast Asia and the Sichuan Basin

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Atmospheric and Oceanic Science Letters 2018年第5期11卷 425-431页

作者： SU Hong-Juan XIN Jin-Yuan MA Yong-Jing LIU Zirui WEN Tian-Xue WANG Shi-Gong FAN Guang-Zhou LI Wei WANG Lu HE Zhi-Ming WANG Yue-Si Plateau Atmosphere and Environment Key Laboratory of Sichuan province Chengdu University of Information TechnologyChengduChina State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjingChina Chinese Academy of Sciences Institute of Mountain Hazards and Environment(IMHE)ChengduChina Jiangxi weather modification office NanchangJiangxi Meteorological BureauChina

The aerosol optical properties and chemical components of PM2.1(particulate matter with a diameter of 2.1μm or less)were investigated at Mount Gongga on the eastern slope of the Tibetan Plateau from April 2012 to December *** annual mean aerosol optical depth(AOD)was 0.35±0.23,and the?ngstr?m exponent was 1.0±*** AOD exhibited higher values in summer and winter,but lower values in spring and *** the observational periods into dry and wet seasons,the authors found that the concentrations of K^+,elemental carbon,secondary inorganic aerosols,and primary and secondary organic carbon in the dry(wet)season were 0.29(0.21),0.88(0.60),7.4(4.5),7.5(5.1),and 3.9(12)μg m?3,*** with trajectory analysis,the authors found that higher concentrations of K^+,elemental carbon,and primary organic carbon indicated the effects of biomass burning from Southeast Asia during the dry ***,the oxidation of volatile organic compounds was the main source of aerosols during the wet season,which originated from the Sichuan Basin.

关键词： Tibetan Plateau aerosol optical depth aerosol components biomass burning regional transport

Impacts of climate warming on heating energy consumption and southern boundaries of severe cold and cold regions in China

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Chinese Science Bulletin 2007年第20期52卷 2854-2858页

作者： CHEN Li FANG XiuQi LI Shuai School of Geography Beijing Normal University Beijing 100875 China Harbin Meteorological Bureau Harbin 150080 China Meteorological Bureau of heilongjiang province Harbin 150001 China

Impacts of climate warming on heating energy consumption and southern boundaries of severe cold and cold regions of China in the past 20 years are analyzed by using daily and monthly average tem- perature data from 590 weather stations in China and based on regulations of Heating Ventilation and Air Conditioning Design Rules (GB50019-2003) and Thermal Design Rules for Civil Building (GB50175-93) (China National Standard). The contribution of climate warming to coal saving for heating during cold seasons in major cities is calculated according to indices of coal consumption for heating in major cities during cold seasons defined in Energy Conservation Design Standard for New Heating Residential Buildings (JCJ26-95). Comparing with the period before 1980, southern boundaries of se- vere cold and cold regions shift toward north up to 2 degrees in latitude since the mid-1980s. Theo- retically, climate warming could contribute to 5%―10% coal savings for heating since the mid-1980s in major cities, and even more since the mid-1990s.

关键词：气候变暖中国寒冷地区能源消耗

Trigger mechanism of a snow burst event in Northeast China

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Atmospheric and Oceanic Science Letters 2021年第2期14卷 13-20页

作者： Baofeng Jiao Lingkun Ran Xinyong Shen Yanbin Qi Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and TechnologyNanjingChina Institute of Atmospheric Physics Chinese Academy of SciencesBeijingChina Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) ZhuhaiChina Jilin weather modification office ChangchunChina

A snow burst event characterized by brief heavy snowfall affected Northeast China and caused serious social impact on 26 January 2017,with the snowband generally aligned with a northeast–southwest-oriented cold *** reanalysis data were used to diagnose the possible trigger *** showed there were two stages:(a)an initial stage far away from the Changbai Mountains,and(b)an enhancement stage under the influence of high *** the initial stage,the coupling of low-level frontogenesis and a favorable convergence pattern caused strong upward motion,contributing to the release of *** the snowband approached the high terrain during the enhancement stage,the various instabilities were triggered by the low-level frontogenesis,terrain circulation,and strong wind shear associated with the low-level ***,a modified Q-vector divergence including generalized potential temperature was calculated to diagnose the vertical *** showed that the frontogenesis terms contributed greatly to the negative Q-vector divergence along the moist isentropes,while the pseudo-vorticity terms played a role in the regions with strong wind shear associated with the low-level jet in the warm section,suggesting both were important in stimulating the ascending *** regions with negative Q-vector divergence had a close relationship with the vertical structure of convection,indicating the potential to track the development of the snowband in the next few hours.

关键词： Snow burst Frontogenesis Q-vector

heilongjiang Silk Road Economic Belt Facilitates Growth, Diplomacy

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China Today 2015年第12期64卷 48-49页

作者： SHA YUCHAO heilongjiang provincial government heilongjiang provincial government’s Information office

DURING his visit to Kazakhstan and Indonesia in September and October 2013, Chinese President Xi Jinping proposed creating the Silk Road Economic Belt and the 21st Century Maritime Silk Road to promote regional connectivity and development. The heilongjiang Land and Maritime Silk Road Economic Belt, part of the Belt and Road Initiative＇s China-Mongolia-Russia Economic Corridor, is also expected to boost development in Northeast China.

关键词：海上丝绸之路经济增长经济带黑龙江印度尼西亚哈萨克斯坦习近平中国