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Observational Characteristics of Cloud Radiative Effects over Three Arid Regions in the Northern Hemisphere

Journal of Meteorological Research 2017年第4期31卷 654-664页

作者： Jiandong LI tianhe wang Ammara HABIB State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of Sciences State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of Sciences Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric SciencesLanzhou University

Cloud–radiation processes play an important role in regional energy budgets and surface temperature changes over arid regions. Cloud radiative effects（CREs） are used to quantitatively measure the aforementioned climatic role. This study investigates the characteristics of CREs and their temporal variations over three arid regions in central Asia（CA）, East Asia（EA）, and North America（NA）, based on recent satellite datasets. Our results show that the annual mean shortwave（SW） and net CREs（SWCRE and NCRE） over the three arid regions are weaker than those in the same latitudinal zone of the Northern Hemisphere. In most cold months（November–March）, the longwave（LW）CRE is stronger than the SWCRE over the three arid regions, leading to a positive NCRE and radiative warming in the regional atmosphere–land surface system. The cold-season mean NCRE at the top of the atmosphere（TOA） averaged over EA is 4.1 W m^-2, with a positive NCRE from November to March, and the intensity and duration of the positive NCRE is larger than that over CA and NA. The CREs over the arid regions of EA exhibit remarkable annual cycles due to the influence of the monsoon in the south. The TOA LWCRE over arid regions is closely related to the high-cloud fraction, and the SWCRE relates well to the total cloud fraction. In addition, the relationship between the SWCRE and the low-cloud fraction is good over NA because of the considerable occurrence of low cloud. Further results show that the interannual variation of TOA CREs is small over the arid regions of CA and EA, but their surface LWCREs show certain decreasing trends that correspond well to their decreasing total cloud fraction. It is suggested that combined studies of more observational cloud properties and meteorological elements are needed for indepth understanding of cloud–radiation processes over arid regions of the Northern Hemisphere.

关键词： arid region cloud fraction cloud radiative effects

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Synthesis of MgO-Modified Mesoporous Silica and Its Adsorption Performance toward CO_2

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Wuhan University Journal of Natural Sciences 2014年第2期19卷 111-116页

作者： LIU Qiming MA Juanjuan ZHOU Yuan wang tianhe Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education/School of Physics and Technology Wuhan University State Key Laboratory of Silicate Materials for Architectures Wuhan University of Technology GuoDian Science and Technology Research Institute

The mesoporous silica modifed with magnesium ox- ide （MgO） was syntbesized by one step method and impregnating method, respectively. The samples were characterized by small angle X-Ray diffraction （XRD）, N2 adsorption-desorption and transmission electron microscopy （TEM）, and the carbon dioxide adsorption capacity was analyzed by thermal gravimetric analysis （TGA）. Compared with the original mesoporous silica （20.7 mg/g）, the CO2 adsorption capacity of MgO-modified mesoporous silica processed by one step method increases to 32.9 mg/g. Although its surface area greatly decreases compared with that of the original mesoporous silica, the MgO-modified mesoporous silica prepared by impregnating reaches an adsorptive value of 31.1 mg/g because the number of basic sites increases on the surface of the mesoporous silica.

关键词： magnesium oxide CO2 adsorption mesoporous silica

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Dusty cloud radiative forcing derived from satellite data for middle latitude regions of East Asia

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Progress in Natural Science:Materials International 2006年第10期16卷 1084-1089页

作者： HUANG Jianping , wang Yujie, wang tianhe and YI Yuhong ( College of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, China Gansu Provincial Meteorological Bureau, Lanzhou 730020, China) College of Atmospheric Sciences Lanzhou University Lanzhou 730000 China Gansu Provincial Meteorological Bureau Lanzhou 730020 China

The dusty cloud radiative forcing over the middle latitude regions of East Asia was estimated by using the 2-year (July 2002-June 2004) data of collocated clouds and the Earth's radiant energy system (CERES) scanner and moderate resolution imaging spectroradiometer (MODIS) from Aqua Edition IB SSF (single scanner footprint). The dusty cloud is defined as the cloud in dust storm environment or dust contaminated clouds. For clouds growing in the presence of dust, the instantaneous short-wave (SW) forcing at the top of the atmosphere (TOA) is about - 275. 7 W/m for cloud over dust (COD) region. The clouds developing in no-dust cloud (CLD) regions yield the most negative short-wave (SW) forcing ( - 311.0 W/m2), which is about 12.8% stronger than those in COD regions. For long-wave (LW) radiative forcing, the no-dust cloud (CLD) is around 102.8 W/m2 , which is 20% less than the LW forcing from COD regions. The instantaneous TOA net radiative forcing for the CLD region is about - 208.2 W/m2, which is 42.1 % larger than the values of COD regions. The existence of dust aerosols under clouds significantly reduces the cooling effect of clouds.

关键词： dust storm cloud radiative forcing global warming dust aerosol-cloud-climate interaction.

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An Overview of Mineral Dust Modeling over East Asia

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Journal of Meteorological Research 2017年第4期31卷 633-653页

作者： Siyu CHEN Jianping HUANG Yun QIAN Chun ZHAO Litai KANG Ben YANG Yong wang Yuzhi LIU Tiangang YUAN tianhe wang Xiaojun MA Guolong ZHANG Key Laboratory for Semi-Arid Climate Change of the Ministry of Education Lanzhou University Atmospheric Science and Global Change Division Pacific Northwest National Laboratory School of Atmospheric Sciences Nanjing University Department of Earth System Science Tsinghua University

East Asian dust（EAD） exerts considerable impacts on the energy balance and climate/climate change of the earth system through its influence on solar and terrestrial radiation, cloud properties, and precipitation efficiency. Providing an accurate description of the life cycle and climate effects of EAD is therefore critical to better understanding of climate change and socioeconomic development in East Asia and even worldwide. Dust modeling has undergone substantial development since the late 1990 s, associated with improved understanding of the role of EAD in the earth system. Here, we review the achievements and progress made in recent decades in terms of dust modeling research,including dust emissions, long-range transport, radiative forcing（RF）, and climate effects of dust particles over East Asia. Numerous efforts in dust/EAD modeling have been directed towards furnishing more sophisticated physical and chemical processes into the models on higher spatial resolutions. Meanwhile, more systematic observations and more advanced retrieval methods for instruments that address EAD related science issues have made it possible to evaluate model results and quantify the role of EAD in the earth system, and to further reduce the uncertainties in EAD simulations. Though much progress has been made, large discrepancies and knowledge gaps still exist among EAD simulations. The deficiencies and limitations that pertain to the performance of the EAD simulations referred to in the present study are also discussed.

关键词： East Asia dust aerosol dust modeling dust emissions long-range dust transport dust radiative forcing

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Thermal evolution effects on the properties of converting Cs-polluted soil into pollucite-base glass-ceramics for radioactive cesium immobilization

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Journal of Materiomics 2021年第6期7卷 1335-1343页

作者： Yong Yang Xin Cao Lifen Shi Zhengyi Zhang Pingping wang Jinwei Li Yangshan Sun Shuyong Chen tianhe wang Liyun Ma Shou Peng State Key Laboratory of Advanced Technology for Float Glass Bengbu233000China Silica-based Materials Laboratory of Anhui Province Bengbu233000China (CNBM)Bengbu Design&Research Institute for Glass Industry Co. LtdBengbu233000China School of Mechanical Engineering Hefei University of TechnologyHefei230009China

The Fukushima nuclear accident in Japan on March 11,2011,produced large amounts of Cs-polluted soil which must be controlled to prevent the spread of hazardous Cs into the *** this paper,the effects of heat treatment on the structure and properties of Cs-containing glass-ceramics,as a simulated nuclear waste form,were systematically *** atoms are chemically bonded in the pollucite structure,and the amorphous phase further encapsulates the pollucite crystals in the glassceramics,thus providing an extra protective layer for the immobilized *** analysis,Raman and FT-IR studies on the glass-ceramics synergistically indicated that the optimum crystallization temperature for pollucite is around 1000℃.The pollucite is predominantly the main crystalline phase with a narrow crystal size distribution between 0.5 and 2 *** leaching test results show that the leaching rate of Cs was very low(3.0×10^(-3) g/(m^(2)·d)).The study offers a practical method for immobilizing Cs in pollucite-base ***,the experimentally obtained data may provide some important references for converting Cs-polluted soil into pollucite-base glass-ceramics waste form.

关键词： Metakaolin Cesium Pollucite Glass-ceramics Thermal evolution

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Screening the effective components in treating dampness stagnancy due to spleen deficiency syndrome and elucidating the potential mechanism of Poria water extract

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Chinese Journal of Natural Medicines 2023年第2期21卷 83-98页

作者： LI Huijun ZHANG Dandan wang tianhe LUO Xinyao XIA Heyuan PAN Xiang HAN Sijie YOU Pengtao WEI Qiong LIU Dan ZOU Zhongmei YE Xiaochuan Hubei Key Laboratory of Resources and Chemistry of Chinese Medicine School of PharmacyHubei University of Chinese MedicineWuhan 430065China Institute of Medicinal Plant Development Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100193China

Poria is an important medicine for inducing diuresis to drain dampness from the middle ***,the specific effective components and the potential mechanism of Poria remain largely *** identify the effective components and the mechanism of Poria water extract(PWE)to treat dampness stagnancy due to spleen deficiency syndrome(DSSD),a rat model of DSSD was established through weight-loaded forced swimming,intragastric ice-water stimulation,humid living environment,and alternate-day fasting for 21 *** 14 days of treatment with PWE,the results indicated that PWE increased fecal moisture percentage,urine output,D-xylose level and weight;amylase,albumin,and total protein levels;and the swimming time of rats with DSSD to different *** highly related components were screened out using the spectrum-effect relationship and *** studies revealed that PWE significantly increased the expression of serum motilin(MTL),gastrin(GAS),ADCY5/6,p-PKAα/β/γcat,and phosphorylated cAMP-response element binding protein in the stomach,and AQP3 expression in the ***,it decreased the levels of serum ADH,the expression of AQP3 and AQP4 in the stomach,AQP1 and AQP3 in the duodenum,and AQP4 in the *** induced diuresis to drain dampness in rats with *** main effective components were identified in *** exerted therapeutic effect by regulating the AC-cAMP-AQP signaling pathway in the stomach,MTL and GAS levels in the serum,AQP1 and AQP3 expression in the duodenum,and AQP3 and AQP4 expression in the colon.

关键词： Poria water extract Dampness stagnancy due to spleen deficiency syndrome Spectrum-effect relationship Effective components Mechanisms

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UAV path planning based on Improved Rapidly-exploring Random Tree

UAV path planning based on Improved Rapidly-exploring Random...

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第30届中国控制与决策会议

作者： SUN-Qinpeng LI-Meng wang-tianhe ZHAO-Chenpeng College of Electrical Engineering University of Jinan School of Control Science and Engineering Shandong University

The RRT algorithm can be used for path planning of Unmanned Aerial Vehicle(UAV).However,the efficiency and success rate of the basic RRT algorithm for path planning need to be *** view of this problem,this paper proposed an improved RRT algorithm which based on the dynamic p value and the dynamic step length,and bidirectional RRT(Bi-RRT) is *** effectiveness and advance of the improved RRT algorithm are verified by simulation experiment.

关键词： Unmanned Aerial Vehicle Rapidly-exploring Random Tree Path planning

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Floating Escherichia coli by Expressing Cyanobacterial Gas Vesicle Genes

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Journal of Ocean University of China 2015年第1期14卷 84-88页

作者： wang tianhe KANG Li LI Jiaheng WU Wenjie ZHANG Peiran GONG Minghao LAI Weihong ZHANG Chunyan CHANG Lei PENG Yong YANG Zhongzhou LI Lian BAO Yingying XU Haowen ZHANG Xiaohua SUI Zhenghong YANG Guanpin wang Xianghong College of Marine Life Science Ocean University of China School of Medicine and Pharmacy Ocean University of China College of Fisheries Ocean University of China College of Information Science and Engineering Ocean University of China School of Mathematical Sciences Ocean University of China Experimental Teaching Center of Marine Life Sciences Ocean University of China

Gas vesicles are hollow, air-filled polyprotein structures that provide the buoyancy to cells. They are found in a variety of prokaryotes. In this study, we isolated a partial gas vesicle protein gene cluster containing gvpA and gvpC20ψ from Planktothrix rubescens, and inserted it into an expression vector and expressed it in E. coli. The gas vesicle was developed in bacterial cells, which made bacterial cells to float on medium surface. We also amplified gvpA and gvpC20ψ separately and synthesized an artificial operon by fusing these two genes with the standardized gene expression controlling elements of E. coli. The artificial operon was expressed in E. coli, forming gas vesicles and floating bacteria cells. Our findings verified that the whole set of genes and the overall structure of gas vesicle gene cluster are not necessary for developing gas vesicles in bacteria cells. Two genes, gvpA and gvpC20ψ, of the gas vesicle gene cluster are sufficient for synthesizing an artificial operon that can develop gas vesicles in bacteria cells. Our findings provided a wide range of applications including easing the harvest of cultured microalgae and bacteria, as well as enriching and remediating aquatic pollutants by constructing gas vesicles in their ceils.

关键词： gas vesicle gene cluster gas vesicle gene buoyancy

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四波混频和级联四波混频效应产生的连续光频率梳（英文）

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红外与激光工程 2018年第7期47卷 83-89页

作者：郭树怀王天鹤郭煌乔斌王晓邢台医学高等专科学校河北邢台054000 天津津航技术物理研究所天津300308 邢台医专第三附属医院河北邢台054000

针对产生光频率梳需要锁模激光种子源的难题,创新性提出了用连续光源产生光频率梳,应用色散平坦高非线性光纤解决了宽光谱范围四波混频和级联四波混频效应的相位失配问题。通过实验展示了近40 nm带宽的光频率梳的形成,光频率梳由低功耗... 详细信息

针对产生光频率梳需要锁模激光种子源的难题,创新性提出了用连续光源产生光频率梳,应用色散平坦高非线性光纤解决了宽光谱范围四波混频和级联四波混频效应的相位失配问题。通过实验展示了近40 nm带宽的光频率梳的形成,光频率梳由低功耗,低成本,连续波种子(法布里-珀罗激光器)生成,无需脉冲激光源。连续光频率梳是由在420 m零色散色散平坦高非线性光纤中的四波混频和级联四波混频效应产生的,频谱带宽扩展了近10倍,频率梳的线宽为4.3 MHz。

关键词：四波混频连续光频率梳线宽MHz 色散平坦高非线性光纤

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基于扰动观测器的永磁直线同步电动机自适应反推互补滑模控制

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中国电机工程学报 2022年第6期42卷 2356-2364页

作者：金鸿雁赵希梅王天鹤沈阳工业大学电气工程学院辽宁省沈阳市110870

针对永磁直线同步电动机(permanent magnet linear synchronous motor,PMLSM)驱动的数控机床易受参数变化、负载扰动以及摩擦力等不确定性影响的问题,提出一种基于质量辨识扰动观测器(disturbance observer with mass identification,DOB-MI)的自适应反推互补滑模控制(adaptive backstepping complementary sliding mode control,ABCSMC)策略。设计ABCSMC方法抑制不确定对系统的影响。通过引入自适应律,ABCSMC的边界层能够实现动态变化,保证系统具有全局鲁棒性,且ABCSMC可对不确定性在线估计并调整,从而提高位置跟踪精度。由于在实际应用中,负载质量变化会对系统性能造成极大的影响,因此,利用离散模型参考自适应辨识理论,设计DOB-MI辨识动子质量并计算出补偿电流以补偿负载扰动对系统的影响。仿真与实验结果表明,该方法提高了系统的位置跟踪精度,对参数变化和负载扰动等不确定性具有极强的抑制能力。

关键词：永磁直线同步电动机质量辨识扰动观测器自适应反推互补滑模控制鲁棒性

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