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Rare Metals 2003年第1期22卷 14-18页

作者： ZOUMingqiang JIANGTiansu WANGDaning ZHAIQingzhou chinaImport－ExportCommodityInspectionTechnologyInstitute Beijing100025China JilinEntry－ExitInspectionandQuarantineBureau Changchun130062China ResearchCenterforNanotechnology ChangchunUniversityofSci

Various experimental conditions were described for the vanadium determinationby graphite furnace atomic absorption spectroscopy (GFAAS). The experiments showed that whenatomization took place under the conditions where the combination of a pyrolytic coating graphitetube and fast raising temperature were used and the temperature was stable, the signal peak shapescould be improved, the sensitivity was enhanced, and the memory effect was removed. The vanadium infood and traditional Chinese medicinal herbs can be accurately determined using the standard curvemethod.

关键词： vanadium determination graphite furnace atomic absorption spectroscopy(GFAAS) food traditional Chinese medicinal herb

Effects of Snow Cover on Ground Thermal Regime： A Case Study in Heilongjiang Province of china

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Chinese Geographical Science 2016年第4期26卷 527-538页

作者： LI Xiaofeng ZHENG Xingming WU Lili ZHAO Kai JIANG Tao GU Lingjia Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130102 China changchun Jingyuetan Remote Sensing Test Station Chinese Academy of Sciences Changchun 130117 China University of Chinese Academy of Sciences Beijing 100049 China College of Electronic Science & Engineering Jilin University Changchun 130012 China

The important effects of snow cover to ground thermal decades. In the most of previous research, the effects were usually regime has received much attention of scholars during the past few evaluated through the numerical models and many important results are found. However, less examples and insufficient data based on field measurements are available to show natural cases. In the present work, a typical case study in Mohe and Beijicun meteorological stations, which both are located in the most northern tip of china, is given to show the effects of snow cover on the ground thermal regime. The spatial （the ground profile） and time series analysis in the extremely snowy winter of 2012-2013 in Heilongjiang Province are also performed by contrast with those in the winter of 2011-2012 based on the measured data collected by 63 meteorological stations, Our results illustrate the positive （warmer） effect of snow cover on the ground temperature （GT） on the daily basis, the highest difference between GT and daily mean air temperature （DGAT） is as high as 32.35℃. Moreover, by the lag time analysis method it is found that the response time of GT from 0 cm to 20 cm ground depth to the alternate change of snow depth has 10 days lag, while at 40 cm depth the response of DGAT is not significant. This result is different from the previous research by modeling, in which the resnonse denth of ground to the alteration of snow depth is far more than 40 cm.

关键词： snow cover ground temperature lag time analysis spline mean difference between ground temperature and air temperature(DGAT)

Characteristics and Cause Analysis of Heavy Haze in changchun City in Northeast china

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Chinese Geographical Science 2017年第6期27卷 989-1002页

作者： MA Siqi CHEN Weiwei ZHANG Shichun TONG Quansong BAO Qiuyang GAO Zongting Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130 102 China Jilin Provincial Academy of Environmental Sciences Changehun 130012 China Laboratory of Research for Middle-High Latitude Circulation and East Asian Monsoon Institute of Meteorological Science of Jilin Province Changehun 130062 China Jilin Province Key Laboratory for Changbai Mountain Meteorology and Climate Change Institute of Meteoro- logical Science of Jilin Province Changehun 130062 China

Northeast china has been reported as having serious air pollution in china with increasing occurrences of severe haze epi- sodes. changchun City, as the center of Northeast china, has longstanding industry and is an important agricultural base. Additionally, changchun City has a long winter requiring heating of buildings emitting pollution into the air. These factors contribute to the complex- ity of haze pollution in this area. In order to analyze the causes of heavy haze, surface air quality has been monitored from 2013 to 2015. By using satellite and meteorological data, atmospheric pollution status, spatio-temporal variations and formation have been analyzed. Results indicated that the air quality in 88.9% of days exceeding air quality index （AQI） level-1 standard （AQI 〉50） according to the National Ambient Air Quality Standard （NAAQS） of china. Conversely, 33.7% of the days showed a higher level with AQI 〉 100. Ex- treme haze events （AQI 〉 300） occurred frequently during agricultural harvesting period （from October 10 to November 10）, intensive winter heating period （from Late-December to February） and period of spring windblown dust （April and May）. Most daily concentra- tions of gaseous pollutants, i.e., NO2 （43.8 gg/m3）, CO （0.9 mg/m3）, SO2 （37.9 gg/m3）, and 03 （74.9 gg/m3） were evaluated within level-1 concentration limits of NAAQS standards. However, particulate matter （PM2.5 and PMI0） concentrations （67.3 ~tg/m3and 115.2 ~g/m3, respectively） were significantly higher than their level-1 limits. Severe haze in spring was caused by offsite transported dust and windblown surface soil. Heavy haze periods during fall and winter were mainly formed by intensive emissions of atmospheric pollutants and steady weather conditions （i.e., low wind speed and inversion layer）. The overlay emissions of widespread straw burning and coal combustion for heating were the dominant factors contributing to haze in autumn, while intensive coal burning during the coldest time was

关键词： air quality air quality index (AQI) air pollutant heavy haze event changchun City

Numerical simulation on drag reduction of revolution body through bionic riblet surface

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Science china(Technological Sciences) 2010年第11期53卷 2954-2959页

作者： ZHANG ChengChun WANG Jing SHANG YanGeng Key Laboratory of Bionics Engineering Ministry of EducationJilin UniversityChangchun 130022China College of Agriculture Department of PhysicsJilin UniversityChangchun 130062China

Numerical simulations of flow fields on the bionic riblet and the smooth revolution bodies were performed based on the SST k-ω turbulence model in order to explain the mechanisms of the skin friction drag reduction, base drag reduction on the riblet surface, and flow control behaviors of riblet surface near the wall. The simulation results show that the riblet surface arranged on the rearward of the revolution body can reduce the skin friction drag by 8.27%, the base drag by 9.91% and the total drag by 8.59% at Ma number 0.8. The riblet surface reduces the skin friction drag by reducing the velocity gradient and turbulent intensity, and reduces the base drag by weakening the pumping action on the dead water region which behind the body of revolution caused by the external flow. The flow control behavior on boundary layer shows that the riblet surface can cut the low-speed flow near the wall effectively, and restrain the low-speed flow concentrating in span direction, thus weaken the instability of the low speed steaks produced by turbulent flow bursting.

关键词： bionic engineering riblet surface drag reduction numerical simulation revolution body

A STUDY ON THE RELATIONSHIP BETWEEN THE SUMMER PRECIPITATION IN NORTHEAST china AND THE GLOBAL SEA SURFACE TEMPERATURE ANOMALY (SSTA) IN PRECEDING SEASONS

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Journal of Tropical Meteorology 2004年第1期10卷 43-52页

作者：孙力沈柏竹安刚唐晓玲 Institute of Meteorological Science of Jilin Province Changchun 130062 China

Based on the NCEP/NCAR reanalysis global SST, 500-hPa geopotential height, 850-hPa wind monthly mean data and summer precipitation from 80 observation stations of Northeast china for the period 1961-2000, the summer precipitation field of Northeast china was decomposed by using the principal component analysis method, then the relationships between the first three precipitation leading modes and the global SSTA in preceding seasons were studied, and the responses of the 500-hPa atmospheric circulation in East Asia to the preceding winter SSTA in north Pacific and its influence on the summer precipitation in Northeast china were probed. The results show that the SSTA, especially the ENSO event in preceding seasons has really very important influence on the occurrence of the whole coincident precipitation episode in Northeast china, and relates to the precipitation episodes of the reverse variation in south-north and in west-east direction closely. The north Pacific SST anomalies in preceding winters are associated with the summer precipitation in Northeast china through its influence on the western Pacific subtropical high and the East Asia subtropical monsoon in summer. Therefore, taking the global SSTA distribution in preceding seasons, especially the ENSO event, as the precursor signal to predict the precipitation anomaly in Northeast china has good reliability and definite indicative significance.

关键词： summer precipitation in northeast china SST anomaly subtropical high climate prediction

Landscape Dynamics and Driving Factors in Da’an County of Jilin Province in Northeast china During 1956-2000

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Chinese Geographical Science 2008年第2期18卷 137-145页

作者： WANG Zongming ZHANG Yubo ZHANG Bai SONG Kaishan GUO Zhixing LIU Dianwei LI Fang Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 China Software College of Jilin University Changchun 130026 China

The landscape pattern of Da’an County, Northeast china has undergone significant changes since the 1950s as a result of climatic change and human activities. The aim of this paper is to quantitatively study landscape pattern and its spatial dynamics of Da’an County at the landscape level over the nearly 50-year span. Patch dynamics were examined ac-cording to land use and land cover change processes built from a series of images, as well as topographic maps, and tem-poral patterns built from landscape pattern metrics. The transition matrix of landscape patch types and changes of various landscape metrics were applied. The results showed that, from 1956 to 2000, the landscape within the study area had un-dertaken a complicated evolution in landscape structure and composition. The outstanding characteristic is that sa-line-alkali land increased and grassland decreased. As some smaller patches amalgamated, the heterogeneity of patch de-creased. All those changes were the synthetic result of both climatic and anthropogenic influences, but the predominant factor was different in different parts. In the southern part of the study area, the landscape pattern changes resulted from the modification of climate obviously, while in the northern part, the landscape pattern changes were mainly caused by human activities, such as the conversion between farmland and saline-alkali land. This phenomenon showed that human activities played more important role in the north than in the south of Da’an County.

关键词： landscape evolution land use change saline-alkali land Da'an County Northeast china

Immunogenicity of recombinant fowl-pox virus co-expressing structural protein precursor P1-2A and proteinase 3C of FMDV

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Chinese Science Bulletin 2004年第8期49卷 823-827页

作者： JINNingyi ZHANGHongyong YINGefeng ZHENGMin LIUTong JIANGWenzheng LIZijian KeyLabofGeneEngineering QuartermasterUniversityofPLAChangchun130062China MedicalCollege FudanUniversityShanghai200032China NormanBethuneUniversityofMedicalSciences Changchun130001China

Two recombinant plasmids, pUTA2P1 and pUTAL3CP1, were constructed by inserting structural pro-tein precursor P1-2A and proteinase 3C of foot-and-mouth disease virus (FMDV) into fowl-pox virus (FPV) recombi-nant vectors pUTA-2 and pUTA-16-LacZ respectively, and two recombinant FPVs (vUTA2P1 and vUTAL3CP1) screened by the RT-PCR, IFA assay and Western blotting assay were obtained successfully. Mice injected respectively with rFPVs were induced high level specific anti-FMDV an-tibodies, increasing of T subtypes, and higher cytotoxicities of splenocytes than those of control groups. These results indicated that a new method was used to construct a poten-tial candidate vaccine of FMDV.

关键词：免疫原性 FMDV P1-2A 口蹄疫重组禽痘病毒蛋白酶 rFPV 疫苗

Interannual Variability of Summer Rainfall over the Northern Part of china and the Related Circulation Features

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Journal of Meteorological Research 2016年第5期30卷 615-630页

作者： BUEH Cholaw LI Yan LIN Dawei LIAN Yi International Center for Climate and Environment Sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 College of Atmosphere Science Chengdu University of Information Technology Chengdu 610225 University of Chinese Academy of Sciences Beijing 100049 Laboratory of Research for Middle High Latitude Circulation and East Asian Monsoon Changchun 130062 Institute of Meteorological Sciences of Jilin Province Changchun 130062

In this study, interannual variability of summer rainfall over the northern part of china （NPC） and associated circulation patterns were investigated by using long-term （1961-2013） observational and reanalysis data. Two important NPC rainfall modes were identified by empirical orthogoual function analysis： the first is characterized by an almost uniformly distributed rainfall anomaly over most parts of the NPC, while the second shows rainfall variability in Northeast china （NEC） and its out-of-phase relationship with that in North china （NC） and the northern part of Northwest china. The results also suggest that the NPC summer rainfall anomalies are also closely associated with those in some other parts of china. It is revealed that the circumglobal teleconnection pattern associated with the anomalous Indian summer monsoon （ISM） and the Polar/Eurasia （PEA） pattern work in concert to constitute the typical circulation pattern of the first rainfall mode. The cooperative engagement of the anomalous ISM circulation and the PEA pattern is fundamental in transporting water vapor to the NPC. The study emphasizes that the PEA pattern is essential for the water vapor transport to the NPC through the anomalous midlatitude westerly. In the second NPC rainfall mode, the typical circulation pattern is characterized by the anomalous surface Okhotsk high and the attendant lower tropospheric circulation anomaly over NEC. The circulation anomaly over NEC leads to a redistribution of water vapor fluxes over the NPC and constitutes an out-of-phase relationship between the rainfall anomalies over NEC and NC.

关键词： summer rainfall northern part of china circumglobal teleconnection pattern Polar/Eurasia pattern water vapor transport

Changes in Atmospheric Circulation during the Winter Regional Extreme Cold Events over china since 1960

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Journal of Meteorological Research 2023年第5期37卷 589-603页

作者： Dongxue FU Yihui DING School of Atmospheric Sciences Nanjing University of Information Science&TechnologyNanjing 210044 Chinese Academy of Meteorological Sciences China Meteorological AdministrationBeijing 100081 Jilin Climate Center Changchun 130062 National Climate Centre China Meteorological AdministrationBeijing 100081

The number of days with occurrence of winter regional extreme cold events(RECEs) in china was found more during 1960/1961–1985/1986(period 1), less during 1986/1987–2005/2006(period 2), but more again during2006/2007–2017/2018(period 3). So far, the differences in the atmospheric circulation favoring RECEs among these three periods are unclear. In this paper, changes in atmospheric circulation during the RECEs over china are examined by using composite analysis based on the station observed temperature data and NCEP–NCAR reanalysis data in winters of 1960/1961–2017/2018. The results show:(1) the stratospheric polar vortex was more active and tended to split before the outbreak of RECEs in period 3 than that in other two periods. The shift of the stratospheric polar vortex to Eurasia helped the upper Arctic cold air to affect the lower latitudes.(2) The troposphere was characterized by a typical or significant three-wave pattern before the outbreak of RECEs in period 2, in contrast to a weakened three-wave pattern in period 1. Compared to periods 1 and 2, the Okhotsk blocking high was stronger in period 3, contributing to the inverted omega-shaped circulation pattern in East Asia–North Pacific section and a shift of global pattern from three-wave to two-wave. The weakened three-wave or two-wave circulation pattern was manifested by the stronger Ural/Okhotsk blocking high, conducive to the strengthening of the meridional circulation and the occurrence of RECEs in East Asia.(3) The Siberian high was the strongest in period 3, followed by period 1, and it was the weakest in period 2. Before the outbreak of RECEs, the Siberian high in period 3 began to intensify one week earlier than that in periods 1 and 2. Thus, the accumulation time of cold air mass in period 3 was the longest. In summary, the synergism of atmospheric circulation at high and low levels in periods 1 and 3 was more conducive to more and strong RECEs than that in period 2. Moreover, the split of the stra

关键词： regional extreme cold events interdecadal variation polar vortex blocking high East Asian trough

Influence of environment and substrate quality on the decomposition of wetland plant root in the Sanjiang Plain,Northeast china

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Journal of Environmental Sciences 2008年第12期20卷 1445-1452页

作者： GUO Xuelian LU Xianguo TONG Shouzheng DAI Guohua College of Urban and Environmental Sciences Northeast Normal University Changchun 130024 China Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchun 130012 China

The litterbag method was used to study the decomposition of wetland plant root in three wetlands along a water level gradient in the Sanjiang Plain,Northeast *** wetlands are Calamagrostis angustifolia(***),Carex meyeriana(***)and Carex lasiocarpa (***).The objective of our study is to evaluate the influence of environment and substrate quality on decomposition rates in the three *** material was used as a standard substrate to evaluate environmental *** native to each we...

关键词： wetland plant root decomposition environment quality substrate quality Sanjiang Plain