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Monitoring of the 2011 spring low ozone events in the Arctic region

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Chinese Science Bulletin 2011年第27期56卷 2893-2896页

作者： LIU NianQing 1,2 , HUANG FuXiang 1,2 WANG WeiHe 1,2 1 national Satellite Meteorological Center, Beijing 100081, china 2 key laboratory of Radiometric Calibration and Validation for environmental Satellites, china Meteorological Administration, Beijing 100081, china national Satellite Meteorological Center key laboratory of Radiometric Calibration and Validation for environmental Satellites China Meteorological Administration

Data from FY-3B SBUS and NOAA SBUV/2 were used to monitor ozone levels in the Arctic region from March 1 to April 5, 2011. Results revealed a significant ozone depletion in the area, with total ozone levels between 200-250 DU. The ozone levels recorded were 100-200 DU below normal, and in some parts the levels were as low as 200 DU, indicating a mini ozone-hole. During the sampling period, the ozone depletion area underwent identifiable expansion and detraction, a rotation around the North Pole from the west to the east, and a longitudinal movement from the Pole, spreading to the mid latitudes. The effects of these rare low ozone events were not only felt in the Arctic, but also extended to densely populated areas between Europe and the middle of Russia. In this region, rapidly increasing levels of ultraviolet radiation were detected at the Earth's surface. Given the significant risk that this poses to both the environment and people's health, this occurrence has significant global implications.

关键词：北极地区臭氧水监测事件人口稠密地区中纬度地区 NOAA 调查结果

Statistical study on the relationship between halo CME and coronal dimming

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Science china(Technological Sciences) 2010年第7期53卷 2020-2024页

作者： LIU Kai1, XIA LiDong2, CHEN Yao2 & SONG HongQiang2 1 School of Earth and Space Sciences, University of Science and Technology of china, Hefei 230026, china 2 Shandong Provincial key laboratory of Optical Astronomy and Solar-Terrestrial environment, School of Space Science and Physics, Shandong University at Weihai, Weihai 264209, china 1. School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China2. Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and Physics Shandong University at Weihai Weihai 264209 China

The data from SOHO/EIT and SOHO/LASCO observations are used to determine the relationship between coronal dimming and full halo CME (coronal mass ejection). The events of full halo CME examined in this study were observed by LASCO co-ronagraphs and taken from the CD AW CME catalog from 1996 to 2008. Dimming events are identified by using difference images taken by EIT at the 195 A passband. We found strong relationship between full halo CMEs and the coronal dimming events, with up to 93.3% of the front-side halo CMEs associated with the EIT 195 A dimming events. Full halo CMEs that show no clear signatures of dimming usually have lower sky plane velocities (<700 km/s) compared to the mean velocity of CMEs associated with dimming.

关键词： Sun coronal mass ejection coronal dimming extreme-ultraviolet

The fluxes and controlling factors of N_2O and CH_4 emissions from freshwater marsh in Northeast china

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Science china Earth Sciences 2010年第5期53卷 700-709页

作者： YU JunBao1,2, LIU JingShuang2, SUN ZhiGao1, SUN WeiDong3, WANG JinDa2, WANG GuoPing2 & CHEN XiaoBing1 1 key Lab of Coastal Envionment Processed, Yantai Institute of Coastal Zone Research for Sustainable Development, Chinese Academy of Sciences, Yantai 264003, china 2 key Lab of Wetland Ecology and environment, Northeast Institute of Geography and Agricultural Ecology, Chinese Academy of Sciences, Changchun 130012, china 3 key laboratory of Isotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, china 1. key Lab of Coastal Envionment Processed Yantai Institute of Coastal Zone Research for Sustainable Development Chinese Academy of Sciences Yantai 264003 China2. Key Lab of Wetland Ecology and Environment Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchun 130012 China3. Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

Nitrous oxide (N2O) and methane (CH4) emissions were measured using a static chamber method in two adjacent plots of freshwater marsh predominated by Calamagrostis angustifolia, one is seasonal waterlogged (SW) and the other without surface water accumulation (NW), in Sanjiang Plain wetland (47°35′N, 133°31′E), northeast china, during 2002-2004. The diurnal and seasonal flux variations of both gases were significantly correlated with 5-cm-soil temperature. The NW marsh is a source of N2O and sink of CH4, while the SW marsh is sink of N2O and source of CH4. Remarkably, we observed a N2O emission peak under Eh of +300 to +100 mV, and CH4 emission peak under Eh of +300 to +400 mV, which indicate additional sources of N2O and CH4 for the freeze-thaw induced emission peaks of N2O and CH4 observed between late July and early August. Further study shows that the additional N2O and CH4 were emitted under the frozen soil after thawing.

关键词： freeze-thaw region freshwater marsh methane nitrous oxide controlling factors

R-calculus without the cut rule

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Science china(Information Sciences) 2011年第12期54卷 2550-2563页

作者： LUO Jie & LI Wei State key laboratory of Software Development environment, School of Computer Science and Engineering, Beihang University, Beijing 100191, china 1. State key laboratory of Software Development environment School of Computer Science and Engineering Beihang University Beijing 100191 China

R-calculus is an inference system for deducing all possible changes when a theory is refuted by the facts. In this paper, we try to eliminate the cut rule in R-calculus by modifying the existing rules and by introducing new rules. The result is the R-calculus without the cut rule, which still preserves the reachability, soundness and completeness as R-calculus does. R-calculus without the cut rule is a formal inference system of logical connective symbols and quantifier symbols solely. It can serve as the theoretical foundation of the automation of revision calculus.

关键词： revision R-calculus cut rule

Effects of Cu^(2+) on characteristic of SV currents

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Science china Chemistry 2006年第6期49卷 560-564页

作者： ZHANG Liping1,2 & YANG Pin1 1. key laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Molecular Science, Shanxi University, Taiyuan 030006, china 2. Institute of environment Science, Taiyuan University of Science and Technology, Taiyuan 030024, china 1. key laboratory of Chemical Biology and Molecular Engineering of Ministry of Education Institute of Molecular Science Shanxi University Taiyuan 030006 China 2. Institute of environment Science Taiyuan University of Science and Technology Taiyuan 030024 China

Applying the patch-clamp technique to vacuoles from Radish we studied the effects of Cu2+ on Slow Vacuolar (SV) current’s characteristic. Our results show that Cu2+ in bath solution at higher concentration inhibits SV currents and the percentage of inhibition increases with increasing concentration and changes with different voltage. When at lower concentration, Cu2+ significantly promotes the SV currents and the promotion ratio decrease with increasing voltage. At the same time, the time constants of activation become lesser after adding Cu2+. These results show that there may be some Cu2+ binding sites on SV channels and binding to which can change SV current’s characteristic.

关键词： the patch-clamp technique, vacuolar, Cu2+, SV channel.

Relationships between δ ^(18)O in summer precipitation and temperature and moisture trajectories at Muztagata, western china

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Science china Earth Sciences 2006年第1期49卷 27-35页

作者： YU Wusheng1,2, YAO Tandong1,2, TIAN Lide1,2, LI Zhen2, SUN Weizhen2 & WANG Yu2 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, CAS, Lanzhou 730000, china 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 Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou 730000 China

Based on summer observations of stable isotope of precipitation at Muztagata, western china, during 2002―2003, this paper presents the relationship between δ 18O in precipitation and air temperature, and discusses the effect of moisture transport on δ 18O in precipitation. Results show that air temperature correlates positively with δ 18O in precipitation, and the temperature effect controls the δ 18O of precipitation in this area. The Muztagata region exhibits high δ 18O values in summer precipi-tation, similar to those shown at stations in adjacent regions. According to the results of our model set up to trace the moisture trajectories, the westerlies and local moisture circulation contribute to varia-tions of oxygen isotopes in precipitation. In addition, the impacts of the moisture transport distance, the moisture transport level, and the incursion of the polar air mass also influence the variations of δ 18O in precipitation. The moisture origins and transport mechanisms also contribute to the variation of δ 18O in precipitation at Muztagata.

关键词： Muztagata, δ18O, precipitation, temperature, moisture transport.

Arbuscular mycorrhizal fungi infection in desert riparian forest and its environmental implications: A case study in the lower reach of Tarim River

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Progress in Natural Science:Materials International 2008年第8期18卷 983-991页

作者： Yuhai Yang, Yaning Chen *, Weihong Li key laboratory of Oasis Ecology and Desert environment, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, china key laboratory of Oasis Ecology and Desert environment Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China

This study was conducted on the desert riparian forest along the lower reach of the inland Tarim River, which is located in the arid region of Northwest *** plant species in 10 families were collected from five monitoring sections,and examined for the infection of arbuscular mycorrhizal fungi (AMF). The impact of different soil factors on AMF infection rate and intensity was compared using the principal component analysis (PCA) method. The results indicate that 11 species are AM and only 4 are non-AM plants. The estimated capacity of AMF infection depends on families of plants and also the parameters (infection rate, infection intensity, fungal spore density) used. The density of fungal spores was relatively higher in Phragmites communis and Populus euphratica in Graminaceae and Salicaceae families, *** infection rate was above 50%in all the AM plants,except Calligonum *** highest infection rate appeared in Alhagi sparsifolia (97%) and Glycyrrhiza inflata (92%). However, when compared by AMF infection intensity, Tamarix spp. became the top one, followed by Alhagi sparsifolia, and Glycyrrhiza inflata was in the middle range of all the species. The PCA has identified that soil total salt, moisture, organic matter, total nitrogen, total P, available K and pH were closely associated with the AMF infection.

关键词： Arbuscular mycorrhiza Infection Ecological restoration Desert riparian forest Soil

A novel aminated polymeric adsorbent for removing refractory dissolved organic matter from landfill leachate treatment plant

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Journal of environmental Sciences 2009年第8期21卷 1089-1095页

作者： ZHANG Long, LI Aimin, WANG Jinnan, LU Yufei, ZHOU Youdong State key laboratory of Pollution Control and Resource Reuse, School of the environment, Nanjing University, Nanjing 210093, china. [a]State key laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing 210093 China

Refractory dissolved organic matter （DOM） from landfill leachate treatment plant was with high dissolved organic carbon （DOC） content. An aminated polymeric adsorbent NDA-8 with tertiary amino groups and sufficient mesopore was synthesized, which exhibited high adsorption capacity to the DOM （raw water after coagulation）. Resin NDA-8 performed better in the uptake of the DOM than resin DAX-8 and A100. Electrostatic attraction was considered as the decisive interaction between the adsorbent and adsorbate. Special attention was paid to the correlation between porous structure and adsorption capacity. The mesopore of NDA-8 played a crucial role during uptake of the DOM. In general, resin in chloride form performed a higher removal rate of DOC. According to the colunm adsorption test, total adsorption capacity of NDA-8 was calculated to 52.28 mg DOC/mL wet resin. 0.2 mol/L sodium hydroxide solution could regenerate the adsorbent efficiently.

关键词： electrostatic interactions chemically modified resin coagulation adsorption pore structure

WAVE-CURRENT INTERACTIONS WITH THREE-DIMENSIONAL FLOATING BODIES

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Journal of Hydrodynamics 2010年第2期22卷 229-240页

作者： LIU Zhen TENG Bin NING De-zhi GOU Ying State key laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024China State key laboratory of Satellite Ocean environment Dyamics Hangzhou 310012 China

A Time-domain Higher-Order Boundary Element Method（THOBEM） is developed for simulating wave-current interactions with 3-D floating *** a Taylor series expansion and a perturbation procedure,the model is formulated to the first-order in the wave steepness and in the current velocity,*** boundary value problem is decomposed into a steady double-body flow problem and an unsteady wave ***-order boundary integral equation methods are then used to solve the proposed problems with a fourth-order Runge-Kutta method for the time *** artificial damping layer is adopted to dissipate the scattering *** from the other time-domain numerical models,which are often focused on the wave-current interaction with restrained bodies,the present model deals with a floating *** numerical results of wave forces,wave run-up and body response are all in a close agreement with those obtained by frequency-domain *** proposed numerical model is further applied to investigate wave-current interactions with a floating body of complicated *** this work,the regular and focused wave combined with current interacting with a truss-spar platform is investigated.

关键词： wave-current interaction floating bodies time-domain simulation Time-domain Higher-Order Boundary Element Method(THOBEM)