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Denitrification in Chongming east tidal flat sediment, Yangtze estuary, china

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Science china Earth Sciences 2006年第10期49卷 1090-1097页

作者： WANG Dongqi1,2, CHEN Zhenlou1,3, XU Shiyuan1,2, HU Lingzhen1 & WANG Jun1,2 1. college of resources & environment, East china normal university, Shanghai 200062, china 2. State Key Laboratory of Estuarine and Coastal Sediment Dynamics and Morphodynamics, East china normal university, Shanghai 200062, china 3. Key Laboratory of Geographical Information Science of Ministry of Education,East china normal university,Shanghai 200062, china 1. college of resources & environment East China Normal University Shanghai 200062 China 2. State Key Laboratory of Estuarine and Coastal Sediment Dynamics and Morphodynamics East China Normal University Shanghai 200062 China 3. Key Laboratory of Geographical Information Science of Ministry of Education East China Normal University Shanghai 200062 China

From July 2003 to July 2004, samples were collected on Chongming Island east tidal flat every two months. The research showed that the nitrous oxide (N2O) production rate was very low in the water, Chongming east tidal flat (CM) sediment was the N2O source of the water. Sediment N2O natural production rate was between -0.08 and 1.74 μmolN·m-2·h-1. N2O natural production rate was higher in the summer. The difference of the N2O natural production rate in the different tidal flats, the correlation between the N2O natural production rate and the denitrification rate, and those with the temperature and DO indicate that middle tidal flat sediment denitrification was the main process of the N2O production, while in the low tidal flat sediment, the production of the N2O came from several processes of the nitrogen cycling. Tidal flat sediment denitrification reaction was stronger in summer and winter but relatively lower in the late autumn and early spring. Seasonal change of the sediment denitrification rate was wide, from 1.12 to 33.34 μmolN·m-2·h-1. Temperature, DO and the coactions of them had the prominent effect on the tidal flat sediment denitrification.

关键词： Yangtze estuary, tidal flat sediment, denitrification, nitrous oxide, effect factor.

Singularity detection of the rabbit electrocardiogram:An evolutionary spectral method

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Progress in Natural Science:Materials International 2009年第10期19卷 1317-1326页

作者： Xinyuan Liua,Dingwu He a,Liuqing Pei b,Suming Zhanga a School of Electronics Engineering and Computer Science,Peking university,beijing 100871,china b college of Information Science and Engineering,beijing normal university,beijing 100875,china [a]School of Electronics Engineering and Computer Science Peking University Beijing 100871 China [b]college of Information Science and Engineering Beijing Normal University Beijing 100875 China

The time-frequency characteristics of the spectral density of non-stationary signals(NSS) in the neighborhood of an instant time point can be determined using the evolutionary spectral *** experimental rabbit model involving ligation of the left anterior descending coronary artery to simulate the physiology of early phase myocardial ischemia(EPMI) has been previously ***,EPMI derived from left coronary artery stenosis is the main symptom of coronary heart diseases including acute myocardial ***,we propose a new algorithm for estimating the evolutionary spectral density functions,which is an effective approach to determine the instantaneous frequency spectra(IFS) of NSS under the uncertainty principle in the time-frequency *** localization singularity information in the data recorded from a living system could be detected by means of the ***(ECG) data recorded from experimental rabbits were analyzed with the new *** showed that the Q’s value of the evolutionary spectral quality number of the QRS-complex data was the characteristic parameter of ECG,and there was a matched connection between the time-frequency characteristics of QRS-complex data and the myocardial ischemia symptoms of the *** results provide valuable information regarding features of the EPMI for use in clinical diagnoses.

关键词： Non-stationary signals Electrocardiogram(ECG) Evolutionary spectrum Instantaneous frequency spectrum(IFS) Myocardial ischemia

A Spatiotemporal Analysis of Urban Growth:A Case Study for Jinan Municipality,china

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Chinese Journal of Population,resources and environment 2006年第4期4卷 48-53页

作者： Yu Bohua1,2,3,Lu Changhe1,Zheng Xinqi 4 1.Institute of Geographical Sciences and Natural resources Research,Chinese Academy Sciences,beijing 100101,china 2.college of resources Science&Technolgy,beijing normal university,beijing 100875,china 3.Graduate School of the Chinese Academy of Science(GUCAS),beijing 100039,china 4.Shandong normal university,Jinan,Shandong 250014,china Institute of Geographical Sciences and Natural resources Research Chinese Academy Sciences Beijing 100101 China college of resources Science & Technolgy Beijing Normal University Beijing 100875 China Graduate School of the Chinese Academy of Science(GUCAS) Beijing 100039China Institute of Geographical Sciences and Natural Resources Research Chinese Academy Sciences Beijing 100101 China Shandong Normal University Jinan Shandong 250014 China

china is experiencing a process of rapid industrialization and urbanization at the cost of agricultural land and environment, particularly in the costal *** study takes Jinan as a case presenting a time-series analysis of urban land expansion from 313 to *** results show that the urban expansion of Jinan city mainly took place in the last 100 years,especially after the economic reform in *** development and economic growth, urban population growth and migration policies were factors driving the urban land *** sprawl resulted in a disappearance of wetlands and a great loss of agricultural land,and over-pumping of ground water that led to disappearance of the city's feature, namely"the city of springs".

关键词： urban land expansion driving forces environmental effects Jinan

Biodegradation of polycyclic aromatic hydrocarbons in sediments from the Daliao River watershed, china

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Journal of environmental Sciences 2009年第7期21卷 865-871页

作者： QUAN Xiangchun, TANG Qian, HE Mengchang, YANG Zhifeng, LIN Chunye, GUO Wei State Key Joint Laboratory of environmental Simulation and Pollution Control, School of environment, beijing normal university, beijing 100875, china. [a]State Key Joint Laboratory of environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China

The Daliao River, as an important water system in Northeast china, was reported to be heavily polluted by polycyclic aromatic hydrocarbons （PAHs）. Aerobic biodegradations of four selected PAHs （naphthalene, phenanthrene, fluorene and anthracene） alone or in their mixture in river sediments from the Daliao River water systems were studied in microcosm systems. Effects of additional carbon source, inorganic nitrogen and phosphorus, temperature variation on PAHs degradation were also investigated. Results showed that the degradation of phenanthrene in water alone system was faster than that in water-sediment combined system. Degradation of phenanthrene in sediment was enhanced by adding yeast extract and ammonium, but retarded by adding sodium acetate and not significantly influenced by adding phosphate. Although PAHs could also be biodegraded in sediment under low temperature （5~C）, much lower degradation rate was observed. Sediments from the three main streams of the Daliao River water system （the Hun River, the Taizi River and the Daliao River） demonstrated different degradation capacities and patterns to four PAHs. Average removal rates （15 or 19 d） of naphthalene, phenanthrene, fluorene and anthracene by sediment were in the range of 0.062-0.087, 0.005-0.066, 0.008- 0.016 and 0-0.059 mg/（L.d）, respectively. As a result, naphthalene was most easily degraded compound, anthracene was the hardest one. In multiple PAHs systems, the interactions between PAHs influenced each PAH biodegradation.

关键词： biodegradation the Daliao River microcosm polycyclic aromatic hydrocarbon sediment

Synthesis and Structural Characterization of One-dimensional Polynuclear Complex [La(bipyN_2O_2)(TFA)_3]_n

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Chinese Chemical Letters 2000年第10期11卷 935-936页

作者： Wen Xiang ZHU, Yun HE (Department of Chemistry, beijing normal university, beijing 100875) (Department of Pharmacy, beijing Staff Medical college, beijing 100036) Department of Chemistry Beijing Normal University Beijing 100875 China Department of Pharmacy Beijing Staff Medical College Beijing 100036 China

A novel polymeric complex [La(bipyN2O2)(TFA)3]n(TFA= trifluoroacetylacetone) was prepared. The X-ray structure analysis revealed that the complex has an infinite one-dimensional supramolecule structure with the 4,4'-bipyridyl-N,N'-dioxide as a bridge. La(III) is coordinated to eight oxygen atoms, six from three trifluoroacetylacetonate anions, two from two 4,4'-bipyridyl-N,N'-dioxide molecules.

关键词： Lanthanum polynuclear complex trifluoroacetylacetone 4,4'-bipyridyl-N,N'-dioxide.

Monitoring Dynamic Change of Land Cover Based on SVM and Satellite Images in Hanoi,Vietnam

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Wuhan university Journal of Natural Sciences 2010年第4期15卷 355-362页

作者： ZHAO Jinling1,2, LIU Chuang1, 3 1. Institute of Geographic Sciences and Natural resources Research, Chinese Academy of Sciences, beijing 100101, china 2. Graduate university of Chinese Academy of Sciences, beijing 100049, china 3. college of resources Science and Technology, beijing normal university, beijing 100875, china Institute of Geographic Sciences and Natural resources Research Chinese Academy of Sciences Beijing China Graduate university of Chinese Academy of Sciences Beijing China college of resources Science and Technology Beijing Normal University Beijing China

An integral method,combining support vector ma-chine (SVM) with remote-sensing analysis techniques,was ex-plored to monitor Hanoi’s dynamic change of land cover. The landsat thematic mapper (TM) image in 1993,the enhanced the-matic mapper plus (ETM+) image in 2000,and the image with the charge-coupled device camera (CCD) on the china-Brazil earth resources satellite (CBERS) in 2008 were used. Six land-cover types,including built-up areas,woodland,cropland,sand,water body and unused land,were identified. The detected results showed visually the rapid urban expansion as well as land-cover change of Hanoi from 1993 to 2008. There were 12 637.54 hm2 cropland de-creased between 1993 and 2000,and 8 227.6 hm2 cropland de-creased between 2000 and 2008. Compared with cropland,wood-land firstly decreased and then increased,and the other types did not change significantly. The results indicate that CBERS dataset has the application potential in world resources researches.

关键词： land cover the china-Brazil earth resources satellite (CBERS) support vector machine (SVM) change detection

Simulating Hydrologic Changes with Climate Change Scenarios in the Haihe River Basin

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Pedosphere 2005年第5期15卷 53-58页

作者： YUAN Fei 1,2, XIE Zheng-Hui1,* 2, LIU Qian1 and XIA Jun 3 1LASG, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029 (china). 2 college of Water resources and environment, Hohai university, Nanjing 210098 (china)3 Institute of Geographical Science & Natural resources, Chinese Academy of Sciences, beijing 100101 (china) Institute of Atmospheric Physics Chinese Academy of Sciences beijing 100029 （china）. 2 college of Water resources and environment Hohai university Nanjing 210098 （china）3 Institute of Geographical Science & Natural resources beijing 100101 （china）

Climate change scenarios, predicted using the regional climate modeling system of PRECIS (providing regional cli-mates for impacts studies), were used to derive three-layer variable infiltration capacity (VIC-3L) land surface model forthe simulation of hydrologic processes at a spatial resolution of 0.25° × 0.25° in the Haihe River Basin. Three climatescenarios were considered in this study: recent climate (1961-1990), future climate A2 (1991-2100) and future climateB2 (1991-2100) with A2 and B2 being two storylines of future emissions developed with the Intergovernmental Panel onClimate Change (IPCC) special report on emissions scenarios. Overall, under future climate scenarios A2 and B2, theHaihe River Basin would experience warmer climate with increased precipitation, evaporation and runoff production ascompared with recent climate, but would be still likely prone to water shortages in the period of 2031-2070. In addition,under future climate A2 and B2, an increase in runoff during the wet season was noticed, indicating a future rise in theflood occurrence possibility in the Haihe River Basin.

关键词： climate change regional climate modeling system runoff VIC-3L model

Non-invasive scanning ion-selective electrode technique and its applications to the research of higher plants

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Progress in Natural Science:Materials International 2007年第6期17卷 625-629页

作者： Sun Tong1, Xu Yue2, Li Peng1, Yu Shangguan2 and Yin Liping1(1. college of Life Science, capital normal university, beijing 100037, china 2. Younger USA Science & Technology Corporation, 7 Dayton Lane, Amherst MA 01002, USA) [a]college of Life Science Capital Normal University Beijing China [b]Younger USA Science & Technology Corporation Amherst MA USA

The process of various ions and molecules getting into and out of cells is critical for plant survival. The non-invasive scanning ion-selective electrode technique (SIET) is a non-invasive method to obtain the information of ions/molecules across membranes in plant. This technique can measure the absolute concentration of ions and molecules, and also their fluxes and directions of movement. The samples to be analyzed can be a single cell, a piece of tissue, a whole organ and even an intact seedling. This article reviews the recent progress made in plant physiology by using this technique and discusses its potentials in future studies on plant physiology.

关键词： non-invasive electrophysiology technique ion-selective electrode ion transport across membrane SIET.

An Analytical Model Used in Formation Evaluation

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石油学报 1998年第4期 145-150页

作者： Funded by National Science Foundation Huang JunqiHuang Junqi, Professor, School of resources and environment, beijing normal university, beijing, china, 100875, Tel:62207656(o), E-mail:jqhuang@*** (Open Research Laboratory of Envir

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关键词： analytical model formation evaluation tracer equation Laplace transform