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Science China(Life Sciences) 2005年第Z1期48卷 136-141页

作者： ZHAO Tianhong, SHI Yi, HUANG Guohong, WANG Yan & SUN Bei Key Laboratory of Terrestrial Ecological Process, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China Shenyang Agricultural University, Shenyang 110161, China Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang China Shenyang Agricultural University Shenyang China

Effects of doubled CO2 and O3 concentration on Soybean were studied in open-top chambers (OTC). Under doubled CO2 concentration, grain yield and biomass increased, the SOD activity, vitamin C (Vc) and carotenoid (Car) content also increased; Superoxide (O2-.) generating rate decreased, relative conductivity and malondialdehyde (MDA) content significantly *** under doubled O3 concentration, the SOD activity, Vc and Car contents declined, resulting in imbalance of activated-oxygen production, enhanced O2-. generating rate and accelerated process of lipid peroxidation and increase in MDA content and ion leakage of leaves. The final result was decreased grain yield and plant biomass. Interactive effects of doubled CO2 and O3 concentrations on soybean were mostly counteractive. However, the beneficial effects of concentration-doubled CO2 are more than compensate the negative effects imposed by doubled O3, and the latter in its turn partly counteracted the positive effects of the former.

关键词： doubled CO2 concentration, doubled O3 concentration, interaction, membrane lipid peroxidation, antioxidative ability, soybean.

Measurement of cytoplasmic Ca^(2+) concentration in Saccharomyces cerevisiae induced by air cold plasma

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Plasma Science and Technology 2018年第4期20卷 2-7页

作者：董晓宇 School of Life Science and Biotechnology Dalian University

In this study, a novel approach to measure the absolute cytoplasmic Caconcentration([Ca]cyt) using the Caindicator fluo-3 AM was established. The parameters associated with the probe fluo-3 AM were optimized to accurately determine fluorescence intensity from the Ca-bound probe. Using three optimized parameters(final concentration of 6 m M probe,incubation time of 135 min, loading probe before plasma treatment), the maximum fluorescence intensity(F?=?527.8 a.u.) and the minimum fluorescence intensity(F?=?63.8 a.u.) were obtained in a saturated Casolution or a solution of lacking Ca. Correspondingly, the maximum [Ca]cytinduced by cold plasma was 1232.5 n M. Therefore, the Caindicator fluo-3 AM was successfully applied to measure the absolute [Ca]cytin Saccharomyces cerevisiae stimulated by cold plasma at atmospheric air pressure.

关键词： cytoplasmic Ca2+ concentration, Saccharomyces cerevisiae, air cold plasma,parameter optimization

Vertical dynamic and thermodynamic characteristics of urban lower boundary layer and its relationship with aerosol concentration over Beijing

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Science China Earth Sciences 2005年第Z2期48卷 25-37页

作者： ZHOU Mingyu, YAO Wenqing, XU Xiangde & YU Haiqing State Key Laboratory on Severe Weather, Chinese Academy of Meteorological Sciences, Beijing 100081, China National Marine Environment Forecasting Center, Beijing 100081, China National Meteorological Center, Beijing 100081, China State Key Laboratory on Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China National Marine Environment Forecasting Center Beijing 100081 China State Key Laboratory on Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China National Meteorological Center Beijing 100081 China

By utilizing observational data from a 325 m tower of the Institute of Atmospheric Physics (IAP), Chinese Academy of Sciences (CAS) on March 19-29, 2001 and August 11-25, 2003, a comprehensive study was conducted on the vertical dynamical and thermodynamic characteristics of the urban lower boundary layer (ULBL) and its relationship with aerosol concentration over Beijing. Firstly, a comparative analysis was made on the gradient data (wind, temperature and humidity), ultrasonic data (atmospheric turbulences) and air-quality observations at different tower heights (47, 120 and 280 m). Secondly, a diagnosis was made to reveal the major features of normalized variances of velocity and temperature, turbulence kinetic energy as well as their relationship with aerosol concentrations. Furthermore, the characteristics of the ULBL vertical structure and the TSP concentration/distribution variations during a sand/dust weather process were also analyzed. The outcome of the study showed that under unstable stratification, the normalized variances of velocity (σu/u*, σv/u*, σw/u*) and temperature (σT/T*) at 47 and 120 m heights fit the Monin-Obukhov similarity (MOS) framework and the fitting formulas were given out accordingly. According to the stratification parameter (z′/L), the stable ULBL could be divided into 2 zones. With z′/L0.1 and the normalized velocity variances tended to increase along with higher stability, but it remained constant for normalized temperature variances. At daytime, the near-surface layer includes two heights of 47 and 120 m, while 280 m has been above it. The ULBL analysis in conjunction with a sand/dust weather process in Beijing in March 2001 indicated that the maximum concentration of Total Suspended Particulates (TSP) at 320 m reached 913.3 μg/m3 and the particles were transported from the upper to lower ULBL, which was apparently rela

关键词： urban boundary layer, turbulence, aerosol concentration, sand/dust weather.

Study on patterns and chemical features of NO effect on marine phytoplankton growth

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Science China Chemistry 2005年第4期48卷 376-384页

作者： ZHANG Zhengbin LIN Cai LIU Chunying XING Lei WU Zhenzhen SUN Feng Institute of Marine Chemistry Ocean University of ChinaQingdao 266003China Institute of Marine ChemistryOcean University of ChinaQingdao 266003China Institute of Marine ChemistryOcean University of ChinaQingdao 266003China Institute of Marine ChemistryOcean University of ChinaQingdao 266003China Institute of Marine ChemistryOcean University of ChinaQingdao 266003China Institute of Marine ChemistryOcean University of ChinaQingdao 266003China

This article discusses the patterns of NO effect on marine phytoplankton growth from chemical *** experimental results of four algae,which are Platymonas hal-golandica ***,Platymonas subcordiformis,Skeletonema costatum and Nitzschia closterium farma minutissima,are as follows:(i) In f/2 medium or f/50 medium,the growth of these four algae was obviously promoted or inhibited when nitric oxide of different concentrations was added once or twice each day during the cultivation;(ii) The NO effects on the growth of marine phytoplankton are in normal *** phytoplankton has different optimum NO concentration,which is consistent with the influence of NO on the growth of high plants;(iii) The effect of NO on Platymonas halgolandica ***,which is a food alga,is different from that on the red tide algae Skeletonema costatum and Nitzschia closterium farma *** authors put forward a new opinion that every alga has its own NO threshold *** the above results may provide new clues to understand the formation of red tide.

关键词： nitric oxide (NO), marine phytoplankton (red tide algae and food algae), optimum NO concentration, NO threshold concentration, influencing patterns.

Water exchange between the subpolar and subtropical North Pacific in an OGCM

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Science China Earth Sciences 2004年第1期47卷 37-48页

作者： Van Scoy Kim University of Wisconsin-Madison 1225 Dayton St. Madison Wl-53706 USA

The water exchange between the subpolar and subtropical gyres of the North Pacific is demonstrated by the simulation of chlorofluorocarbon (CFC) using an ocean general circulation model. The simulated CFC concentration in the North Pacific is in good agreement with observations. The water exchange is clearly illustrated by the tongues of CFC concentration. The subpolar waters with high CFC are transported southward into the eastern subtropical gyre, whereas the subtropical waters with low CFC are transported northward into the western subpolar gyre. The simulated exchange transport along 42°N in the layer of σθ < 26.8 indicates that the northward mass transport is about 15 Sv (1 Sv = 106 m3 ? s ) west of 165°E, and about 5 Sv between 175°W and 150°W. The southward mass transport is about 5 Sv between 165°E and 175°W, and about 2 Sv east of 150°W.

关键词： water exchange, CFC concentration, North Pacific.

Pollution characteristics of atmospheric fine particles and their secondary components in the atmosphere of Shenzhen in summer and in winter

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Science China Chemistry 2006年第5期49卷 466-474页

作者： NIU Yuwen1,2,HE Lingyan1,2,HU Min2,ZHANG Jing2 & ZHAO Yunliang2 1. Shenzhen Graduate School of Peking University,Shenzhen 518055,China 2. State Joint Key Laboratory of Environmental Simulation and Pollution Control,College of Environmental Sciences,Peking University,Beijing 100871,China Shenzhen Graduate School of Peking University Shenzhen China State Joint Key Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences Peking University Beijing China

Two field measurements for atmospheric fine particles were conducted in Baoan district of Shenzhen during the summer and winter in 2004. Totally 30 sets of 24 h samples were collected, and then the mass concentrations and chemical compositions were determined. The seasonal varia- tions and secondary pollution characteristics of fine particles during the sampling periods were dis-cussed with meteorological factors. The results show that seasonal variations of atmospheric particles are significant in Shenzhen. The average mass concentrations of PM2.5 and PM10 in summer were 35 μg·m-3 and 57 μg·m-3, respectively, and those in winter were 99 μg·m-3 and 135 μg·m-3, respec-tively. The concentrations of both PM2.5 and PM10 in winter increased 184% and 137%, respectively, compared to those in summer. PM2.5 accounted for 61% and 75% of PM10 in summer and in winter, respectively, indicating severe fine particle pollution in Shenzhen. During the summer and winter sampling periods, the mean OC/EC ratios were 3.4 and 1.6, respectively. The estimated secondary organic carbon (SOC) averagely accounted for 56% and 6% of the total OC in summer and in winter, respectively, which implies a major contribution of SOC to OC in summer. During the continuous high temperature period in summer, both the concentrations and fractions of secondary aerosol compo-nents in PM2.5 were highly elevated, suggesting severe secondary pollution again. The prevailing wind was from South China Sea in summer, and the air quality was good. The prevailing wind in winter was from China's Mainland to the north, and the polluted air mass led to poor air quality.

关键词： PM2.5, mass concentration, secondary pollution, seasonal variation, Shenzhen.

Variations of near-surface atmospheric CO_(2)and H_(2)O concentrations during summer on Muztagata

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Science China Earth Sciences 2006年第1期49卷 18-26页

作者： XU Baiqing1,2, YAO Tandong1,2, LU Anxin2, GUO Xuejun, LIU Xianqin2 & LI Zhen2 1. Laboratory of Environment and Process on Tibetan Plateau, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, China 2. Key Laboratory of Cryosphere and Environment, Jointly Established by Cold and Arid Regions Environmental and Engi-neering Research Institute and Institute of Tibetan Plateau Research, Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences, China Meteorological Administration, Lanzhou 730000, China Laboratory of Environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China Key Laboratory of Cryosphere and Environment Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou China

Expeditions during the summers of 2002 and 2003 implemented continuous monitoring of near-surface (2 m height) atmospheric CO2 and H2O concentrations at the 4500 m elevation on Muztagata. The resultant data sets reveal a slight decrease of CO2 concentrations (of about 5 μmol·mol?1) and changes in the diurnal variations from the end of June to the middle August. The daily maximum CO2 concentrations occur between 02:30―05:30 AM (local time) and the minimum levels occur between 12:00―15:30 PM. The atmospheric CO2 concentrations in the summer of 2002 were around 5 μmol·mol?1 lower than those during the same period of 2003, whereas the diurnal amplitude was higher. In contrast, we found that the daily mean atmospheric H2O content in 2003 was much lower than that in 2002 and there exists a striking negative correlation between CO2 and H2O con-centrations. We therefore suggest that the near-surface atmospheric CO2 concentration is affected not only by photosynthesis and respiration, but also by the air H2O content in the glaciated region around Muztagata.

关键词： atmospheric CO2 and H2O concentration, continuous monitoring, glaciation region, Muztagata.

Characteristics of Suspended Sediment concentrations over the Areas Adjacent to Changjiang River Estuary, the Summer of 1998

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Marine Science Bulletin 2000年第1期2卷 14-24页

作者：高抒程鹏汪亚平曹奇源 Institute of Oceanology Chinese Academy of Sciences Qingdao 266071

A major flood event occurred within the drainage basin of the Changjiang River in June-August, 1998. Survey over the East China Sea adjacent to the Changjiang River estuary shows that during the flood the turbid water (with a suspended sediment concentration of higher than 10 mg l-1) °°′reached 123E. Stratification of the concentration layers was present near 12215E, with the concentration in the bottom layer being 3 times that in the upper layer, in response to sediment °°settling processes. The concentration is the lowest in the area of 126E^127E, representing a characteristic of the Kuroshio water. Although there was some expansion of the turbid water extension compared with the winter situations with low freshwater discharges, the suspended sediment does not appear to disperse towards the northeast from the Changjiang River. Further, several secondary high suspended sediment concentration centers were present on the East China Sea continental shelf, which may result from resuspension of the seabed sediment or advection of seawater containing suspended matter. In order to understand the processes of fine-grained sediment transport/deposition and their impact on the flux of chemical constituents on the shelf, further studies on the hydrodynamics, temperature, salinity and nutrient characteristics are required.

关键词： Suspended sediments concentration, Material flux, Changjiang estuary, East China Sea

Vertical structures of PM_(10) and PM_(2.5) and their dynamical character in low atmosphere in Beijing urban areas

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Science China Earth Sciences 2005年第Z2期48卷 38-54页

作者： CHAN Chuenyu LI Yoksheung WONG Kamhang Department of Civil and Structural Engineering The Hongkong Polytechnic UniversityHongkongChina

The vertical structures and their dynamical character of PM2.5 and PM10 over Beijing urban areas are revealed using the 1 min mean continuous mass concentration data of PM2.5 and PM10 at 8, 100, and 320 m heights of the meteorological observation tower of 325 m at Institute of Atmospheric Physics, Chinese Academy of Sciences (IAP CAS tower hereafter) on 10―26 August, 2003, as well as the daily mean mass concentration data of PM2.5 and PM10 and the continuous data of CO and NO2 at 8, 100 (low layer), 200 (middle layer), and 320 m (high layer) heights, in combination with the same period meteorological field observation data of the meteorological tower. The vertical distributions of aerosols observed on IAP CAS tower in Beijing can be roughly divided into two patterns: gradually and rapidly decreasing patterns, I.e. The vertical distribution of aerosols in calm weather or on pollution day belongs to the gradually decreasing pattern, while one on clean day or weak cold air day belongs to the rapidly decreasing pattern. The vertical distributive characters of aerosols were closely related with the dynamical/thermal structure and turbulence character of the atmosphere boundary layer. On the clean day, the low layer PM2.5 and PM10 concentrations were close to those at 8 m height, while the concentrations rapidly decreased at the high layer, and their values were only one half of those at 8 m, especially, the concentration of PM2.5 dropped even more. On the clean day, there existed stronger turbulence below 150 m, aerosols were well mixed, but blocked by the more stronger inversion layer aloft, and meanwhile, at various heights, especially in the high layer, the horizontal wind speed was larger, resulting in the rapid decrease of aerosol concentration, I.e. Resulting in the obvious vertical difference of aerosol concentrations between the low and high layers. On the pollution day, the concentrations of PM2.5 and PM10 at the low, middle, and high layers dropped successively

关键词： PM10, PM2.5, mass concentration, vertical structure, dynamical character, footprint analysis.