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Progress in Natural Science:Materials International 2002年第6期 47-50页

作者： ZHANG Xin , wang Bin, JI Zhongzhen and LIN Wantao(lasg,{2., chinese academy of sciences, Beijing 10002., china) lasg Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

On July 2.-2., 1998, a torrential rain with 2.-hour rainfall of 2.6mm occurred in Wuhan, Hubei Province of china. In this study, a three-dimensional variational data assimilation system developed at the Fifth-Generation Pennsylvania State University/National Center for atmospheric Research Mesoscale Model ( MM5 ) along with conventional rawinsonde sounding and surface observation is used for modeling the heavy rain. It successfully incorporates observational data of temperature, humidity and wind, and provides an optimal analysis being in favor of the formation of heavy rain. The 2.-hour rainfall predicted by the new scheme is 109 mm rather tban 2.5 mm forecasted by control experiment. Furthermore, the forecasted accuracy of location and time-variation of hourly rainfall reproduced by this model is also improved.

关键词： variational data assimilation torrential rain numerical modeling.

Low-frequency fluctuations in the magnetosheath: Double Star TC-1 and Cluster observations

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Science china(Technological sciences) 2008年第10期51卷 1626-1638页

作者： DU Jian1,2.wang Chi1, SONG Pu3,4 & ZHANG TieLong5 1 State Key Laboratory of Space Weather, Center for Space Science and Applied Research, chinese academy of sciences, Beijing 100190,{2. 2.Graduate School, chinese academy of sciences, Beijing 100049,{2. 3 Earth, Environmental and atmospheric sciences Department, University of Massachusetts, Lowell, Mas-sachusetts MA 01854, USA 4 Center for atmospheric Research, University of Massachusetts, Lowell, Massachusetts MA 01854, USA 5 Space Research institute, Austrian academy of sciences, Graz A-8010, Austria State Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China Graduate School Chinese Academy of Sciences Beijing 100049 China Earth Environmental and Atmospheric Sciences Department University of Massachusetts Lowell Massachusetts MA 01854 USA Center for atmospheric Research University of Massachusetts Lowell Massachusetts MA 01854 USA Space Research institute Austrian Academy of Sciences Graz A-8010 Austria

The magnetic field variations are analyzed in the range of time periods from 4 s to 2.0 s in the magnetosheath observed by the Double Star TC-1 and Cluster in 2.04. The characteristics of the magnetic field fluctuations are strongly controlled by the angle between the upstream interplanetary magnetic field (IMF) and the normal of the bow shock. Generally speaking, the magnetic field fluctuations in the quasi- parallel magnetosheath are more intense than those in the quasi-perpendicular ones. Almost purely compressional waves are found in the quasi-perpendicular magnetosheath. With the increase of the local plasma β, both the magnitude and direction of the magnetic field fluctuate more intensely. There exists an inverse correlation between the local temperature anisotropy T⊥/T|| and the plasma β.

关键词： low-frequency fluctuations magnetosheath MHD instabilities

A new method to prepare clean cuticular membrane from fossil leaves with thin and fragile cuticles

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Science china Earth sciences 2011年第2期54卷 223-227页

作者： wang Li1,2.& LENG Qin1,3 1 State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing institute of Geology and Palaeontology,{2. academy of sciences,Nanjing 2.0008,china 2.Graduate School of chinese academy of sciences,Beijing 100049,china 3 Department of Science and Technology,Bryant University,Smithfield RI 02.17,USA 1. State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China2. Graduate School of Chinese Academy of Sciences Beijing 100049 China3. Department of Science and Technology Bryant University Smithfield RI 02917 USA

Leaf cuticle analysis has long been a powerful tool for fossil plant identification, systematics, and palaeoclimatological recon- struction. In recent decades the application of stomatal frequency data that are relied on precise calculation of stomata on plant fossil cuticles to reconstruct ancient atmospheric CO2.concentration made the preparation of cuticular membrane with sufficient size a critical technique in palaeoclimatological research. However, for plants with originally thin and fragile cuticles, e.g., most deciduous plants, conventional techniques sometimes fail to obtain cuticular membranes with sufficient size, or sometimes unable to recover any. This has largely hampered the usage of fossil cuticle analysis in palaeobotanical and palaeo- climatological research. Here, we describe a new method using clear nail polish as a medium to ＂strengthen＂ the originally thin and fragile cuticles prior to maceration procedures. We demonstrate the method by using middle Eocene Metasequoia fossils that were notorious for the difficulty of recovering large-sized clean cuticular membranes due to their thin and fragile nature. Metasequoia, with well-documented and widely-distributed fossil records since the Late Cretaceous and with a living repre- sentative, 114. glyptostroboides, as a comparative reference, bas been widely used as a model genus for the study of evolution of plants, palaeoclimatological reconstruction, and plant adaptation to climate changes. But its deciduous habit produces thin cuticles and makes the preparation of clean cuticular membranes a tedious process. The new method successfully allows us to recover its delicate cuticular membranes with sufficient sizes for SEM observation and stomatal frequency analysis.

关键词： fossil leaf cuticle Metasequoia new method thin and fragile cuticle SEM observation stomatal frequency CO2

Use of the advanced microwave sounding unit data to improve typhoon prediction

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Progress in Natural Science:Materials International 2009年第3期19卷 369-376页

作者： Guo Deng a,*, Dalin Zhang b, Tong Zhu c, Angsheng wang d a National Meteorological Center, Beijing 100081, china b Department of {2. and Oceanic Science, University of Maryland, Maryland 2.742. USA c Cooperative institute for Research in the Atmosphere, Colorado State University, Colorado 8052., USA d institute of atmospheric physics, chinese academy of sciences, Beijing 10002., china [a]National Meteorological Center Beijing 100081 China [b]Department of Atmospheric and Oceanic Science University of Maryland Maryland 20742 USA [c]Cooperative Institute for Research in the Atmosphere Colorado State University Colorado 80523 USA [d]Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The effects of incorporating the advanced microwave sounding unit (AMSU-A) data with a modified Zhu-Zhang-Weng vortex- bogussing algorithm on typhoon prediction are examined through the use of the PSU/NCAR Mesoscale Model version 5 (MM5). The AMSU-A data contain the vertical distribution of the retrieved temperature from satellite brightness temperature, with the geopo- tential height and wind fields derived through a series of statistical and diagnostic calculations. The advantages of the modified vortex- bogussing algorithm include the incorporation of realistic asymmetric typhoon structures, the balanced dynamics with the background field, the easiness to implement and the effcient computations. To test the effciency of this vortex-bogussing algorithm, the Typhoon Dan event in 1999 is simulated by incorporating the derived AMSU-A fields into the initial conditions of the MM5 modeling system. Results show significant improvements in the track and intensity of the storm, as compared to the simulation without the AMSU-A data. Therefore, this modified vortex-bogussing algorithm can be easily implemented on any typhoon modeling system, which will improve the real-time forecast of tropical cyclones.

关键词： AMSU Satellite retrieval Typhoon prediction

Relationship and its instability of ENSO--chinese variations in droughts and wet spells

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Science china Earth sciences 2007年第1期50卷 145-152页

作者： SU MingFeng1,2.& wang huijun1 1 Nansen-Zhu International Research Center,{2., chinese academy of sciences, Beijing 10002., china 2.Graduate University of chinese academy of sciences, Beijing 100039, china 1. Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Graduate University of chinese academy of sciences Beijing 100039 China

Monthly data of Self-Calibrated Palmer Drought Severity Index (PDSI) from 1951 to 2.00 are calculated using historical precipitation and temperature data for chinese 160 stations. Temporal and spatial pat-terns of the first empirical orthogonal function (EOF) of the PDSI reveals a fairly linear trend resulting from trends in precipitation and surface temperature, which is similar to the linear PDSI trend during 1951―2.00 calculated using all monthly data. The EOF analysis also reveals that the leading mode correlates significantly with ENSO events in time and space. The ENSO EOF shows that during the typical warm phase of ENSO, surface conditions are drier in most regions of china, especially North china, but wetter than normal in the southern regions of Changjiang River, and Northwest china. During the typical cold phase of ENSO, these anomalies reverse sign. From 1951 to 2.00, there are large multi-year to decadal variations in droughts and wet spells over china, which are all closely related to strong El Nio events. In other words, when one strong El Nio event happens, there is a possible big variability in droughts and wet spells over china on the multi-year or decadal scale. Studies also sug-gest that during the last 2.3 decades climate changes over china, especially North china's drying and northwest china's wetting, are closely related to the shift in ENSO towards warmer events and global warming since the late 1970s. The instability of the relationship is also studied. It is revealed that there is a good correlation between ENSO and chinese variations in droughts and wet spells in the 3―8-year band, but the correlation between ENSO and chinese variations in droughts and wet spells is instable. Studies suggest that there are decadal changes in the correlation: the wavelet coherency between ENSO and chinese variations in droughts and wet spells is high during 1951―1962.and 1976―1991, but low during 1963―1975 and 1992.2.00.

关键词： PDSI variations droughts and wet Spells ENSO instability.

Dipole anomaly in the Arctic atmosphere and winter Arctic sea ice motion

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Science china Earth sciences 2005年第9期48卷 1529-1536页

作者： WU Bingyi1, ZHANG Renhe1 & wang Jia2.1. chinese {2. of Meteorological sciences, Beijing 100081, china 2. International Arctic Research Center, University of Alaska Fairbanks, AK 99775, USA 1. chinese academy of Meteorological {2. 100081 Beijing China 2. International Arctic Research Center University of Alaska Fairbanks 99775 AK USA

This paper investigates a previously-ignored atmospheric circulation anomaly-di- pole structure anomaly in the arctic atmosphere, and its relationship with the winter sea ice mo- tion, based on analyses of the International Arctic Buoy Programme Data (1979―1998) and datasets from the National Center for Environmental Prediction (NCEP) and the National Center for atmospheric Research (NCAR) for the period of 1960―2.02. The dipole structure anomaly is the second-leading mode of EOF of monthly mean SLP north of 70°N during the winter season (Oct.―Mar.), which accounts for 13% of the variance. One of its two anomaly centers is over the Canadian Archipelago; the other is situated over northern Eurasia and the Siberian marginal seas. Due to the dipole structure anomaly’s strong meridionality, it becomes an important mechanism to drive both anomalous sea ice export out of the Arctic Basin and cold air outbreaks into the Barents Sea, the Nordic Seas and northern Europe.

关键词： dipole anomaly, winter season, Arctic, sea ice motion, sea ice export.

Long term monitoring of urban subsidence by Permanent Scatterer DInSAR

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Progress in Natural Science:Materials International 2007年第1期17卷 107-111页

作者： TANG Yixian, ZHANG Hong and wang Chao ( The chinese Remote Sensing Satellite Ground Station,{2., Beijing 100086, china State Key Laboratory of Remote Sensing IRSA,{2., Beijing 100101, china) [a]The chinese Remote Sensing Satellite Ground Station Chinese Academy of Sciences Beijing China [b]State Key Laboratory of Remote Sensing IRSA Chinese Academy of Sciences Beijing China

When using differential SAR interferometry (DInSAR) to monitor the surface deformation over a long time scale, it is often strongly affected by the spatial and temporal decorrelations and atmospheric dishomogeneities. The recently developed Permanent Scatterers (PS) technique proposed by Fertti et al. can overcome these difficulties by interpreting time-series of interferometric phase only at coherent point scatterers. In this study, we apply this PS technique using 2. ERS-1/2.scenes from 1992.to 2.00 to monitor the subsidence in Suzhou. By using the linear deformation model, the deformation map in Suzhou urban area over the eight years is obtained. And the calculated results are in good agreement with the measurements of leveling.

关键词： Permanent Scatterer differential SAR interferometry urban subsidence.

A brief introduction to the Nonlinear atmospheric Dynamics Research Group in the State Key Laboratory of lasg

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Progress in Natural Science:Materials International 2002年第3期 81-82页

作者： MU Mu and wang Jiafeng(institute of {2. physics, chinese academy of sciences, Beijing 10002., china) institute of atmospheric {2. Chinese Academy of SciencesBeijing 100029China

Nonlinear atmospheric dynamics is an interdisciplinary branch of atmospheric {2., geophysical fluid dynamics and nonlinear {2.. As a basis for numerical weather prediction and short-term climate prediction, ... 详细信息

关键词： Ph A brief introduction to the Nonlinear atmospheric Dynamics Research Group in the State Key Laboratory of lasg

Distinct Effects of Three Tea Varieties Made Green Teas on Improving Diabetic Dyslipidemia Induced by High-Fat Diet in C57BL/6J Mice

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Food Science and Human Wellness 2024年

作者： Wei Gu Zhutong wang Guohuo Wu Huimin Guo huijun Cheng Cong Li Linbo Chen Daxiang Li Zhongwen Xie State Key Laboratory of Tea Plant Biology and Utilization， School of Tea and Food sciences & Technology， Anhui Agricultural University Center for Biotechnology， Anhui Agricultural University College of Life sciences， Anhui Agricultural University Tea Research institute， Yunnan academy of Agricultural {2.

Currently， cultivated tea plants are classified into three varieties， namely， C. sinensis var. sinensis， C. sinensis var. assamica， and C. sinensis var. kucha. Three tea varieties made green teas (TVGTs) are widely consumed worldwide. However， a comparative investigation of the beneficial effects， mechanism， and characteristic compounds of TVGTs has not been reported. Here， three representative tea plant varieties， namely， C. sinensis var. sinensis cv. Fuding (FD)， C. sinensis var. assamica cv. Yunkang 10 (YK)， and C. sinensis var. kucha (KC)， planted in the same garden， were used to make green teas utilizing the same standard procedure. Our findings show that the TVGTs effectively improved hyperglycemia， obesity， dyslipidemia， fatty liver， and mesenteric artery (MA) hypercontractility in mice with diabetes and obesity induced by a high-fat diet (HFD) after 11- and 2.-week interventions， with YK being the most effective at 2. weeks. Liver lipidomics indicated that the TVGTs restored the glycerophospholipid and sphingolipid balance and reduced triglycerides， with YK demonstrating superior effects. The TVGTs， particularly YK， suppressed triglyceride synthesis through the ARV1-FXR-SHP-SREBP-1c pathway. A chemical profile analysis revealed that YK green tea had enriched active compounds， including caffeine， quinic acid， L-theanine， gallic acid， and catechins， compared with FD and KC green teas， which may contribute to ameliorating diabetic dyslipidemia via synergistic action. As a representative tea variety of C. sinensis var. assamica， YK green tea was found to be superior to the other two green teas in preventing and treating diabetic dyslipidemia， especially with long-term consumption. These data provide important information for tea plant breeders and tea consumers.

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Local and non-local sources of airborne particulate pollution at Beijing——The ratio of Mg/Al as an element tracer for estimating the contributions of mineral aerosols from outside Beijing

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Science china Chemistry 2005年第3期48卷 253-264页

作者： HAN Lihui1, ZHUANG Guoshun1,2.3, SUN Yele1 & wang Zifa3 1. The Center for atmospheric Environmental Study, Department of Chemistry, Beijing Normal University, Beijing 100875,{2. 2. Center for atmospheric Chemistry Study, Department of Environmental Science & Engineering, Fudan University, Shanghai 2.0433,{2. 3. LAPC/NZC, institute of atmospheric physics, CAS, Beijing 10002.,{2. 1. The Center for atmospheric Environmental Study Department of Chemistry Beijing Normal University 100875 Beijing China 2. Center for atmospheric Chemistry Study Department of Environmental Science & Engineering Fudan University 200433 Shanghai China 3. institute of atmospheric physics CAS LAPC/NZC 100029 Beijing China

A new element tracer technique has firstly been established to estimate the contri-butions of mineral aerosols from both inside and outside Beijing. The ratio of Mg/Al in aerosol is a feasible element tracer to distinguish between the sources of inside and outside Beijing. Mineral aerosol, inorganic pollution aerosol mainly as sulfate and nitrate, and organic aerosol are the major components of airborne particulates in Beijing, of which mineral aerosol accounted for 32.―67% of total suspended particles （TSP）, 10%―70% of fine particles （PM2.5）, and as high as 74% and 90% of TSP and PM2.5, respectively, in dust storm. The sources from outside Beijing contributed 62. （38%―86%） of the total mineral aerosols in TSP, 69% （52.―90%） in PM10, and 76% （59%―93%） in PM2.5 in spring, and 69% （52.―83%）, 79% （52.―93%）, and 45% （7%―79%） in TSP, PM10, and PM2.5, respectively, in winter, while only2.% in summer and autumn. The sources from outside Beijing contributed as high as 97% during dust storm and were the dominant source of airborne particulates in Beijing. The contributions from outside Bei-jing in spring and winter are higher than those in summer, indicating clearly that it was related to the various meteorological factors.

关键词： mineral aerosol local sources non-local sources dust storm re-suspended dust element tracer technique.