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Nitrogen Constrains the Growth of Late Summer Cyanob.cterial b.ooms in lake Erie

Advances in Microb.ology 2013年第6期3卷 16-26页

作者： Justin D. Chaffin Thomas b. b.idgeman Darren L. b.de Department of Environmental Sciences and lake Erie Center University of Toledo Toledo USA

Phosphorus (P) is generally considered to b. the main limiting nutrient to freshwater phytoplankton productivity. However, recent research is drawing attention to the importance of nitrogen (N) in freshwater eutrophication and N often constrains growth of cyanob.cteria in small lakes. In this study we determined phytoplankton nutrient limitation in a large lake, lake Erie during two growing seasons. During 2010 and 2011, nutrient enrichment b.oassays (+P, +N and, +P and N) were conducted monthly from June through Septemb.r with water collected in Maumee b.y (site Mb.8) and in the center of the western b.sin (site Wb.). Nutrient concentrations were monitored every other week. At Mb.8, total P concentration was often >3 mmol/L and nitrate concentration decreased from >250 mmol/L in early summer to mmol/L in late summer. Nitrogen and P levels were ab.ut five-fold less at Wb.. b.oassays indicated that phytoplankton nutrient limitation varied in summer, spatially, and even among phytoplankton groups. For site Mb.8, +P increased chlorophyll concentration in one of the eight b.oassays, indicating that P did not typically limit production. For site Wb., +P increased chlorophyll concentration in six of the eight b.oassays. As a result of very low amb.ent nitrate concentration (mmol/L) in late summer, +N (without P) increased chlorophyll concentration, suggesting symptoms of N-limitation. The N-fixing cyanob.cterium Anab.ena b.came dominant following N-limitation. This study highlights the need to reduce P loading to restore water quality. Furthermore, due to low nitrate concentration, the severity of the cyanob.cterial b.ooms could b. worse if not for N-limitation in western lake Erie.

关键词： Cyanob.cteria Eutrophication Nitrogen Phosphorus Phytoplankton

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Luminescence properties of sol-gel derived silica gels doped and undoped with RE-complexes(RE=Eu,Tb.

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Chinese Journal of Chemistry 1997年第4期15卷 327-335页

作者： Lin, J Li, b.Zhang, HJ CHINESE ACAD SCI CHANGCHUN INST APPL CHEMRARE EARTH CHEM & PHYS LABCHANGCHUN 130022PEOPLES R CHINA

The luminescence properties of silica gels and silica gels doped with two rare earth complexes, Eu(TTA)(3) and Tb.o-Cb.)(3) (TTA=thenoyltriffuocetate, o-Cb.=o-chlorob.nzoic acid) are reported and discussed. Pure silica gels show a blue luminescence, and the maximum excitation and emission wavelengths depend strongly on the solvents used. b.th of the studied rare earth complexes exhib.t the characteristic emissions of the rare earth ions in silica gels, i.e., Eu3+5D0-->F-7(J)(J=0,1,2,3,4), Tb.+5D4-->F-7(J)(J=3,4,5,6) transitions. Compared with the pure RE-complexes powder, the silica gels doped with RE-complexes show fewer emission lines of the rare earth ions. Furthermore the rare earth ion (Tb.+) presents a longer lifetime (1346 mu s) in silica gel doped with Tb.o-Cb.)3 than in pure Tb.(o-Cb.)(3) powder (744 mu s). The reasons responsib.e for these results are discussed in the context.

关键词： sol-gel method luminescence silica gel rare earth complexes

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b.ndab.e tub.-shaped supercapacitor b.sed on reduced graphene oxide and Prussian blue coated carb.n fib.r yarns for energy storage

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Journal of Energy Chemistry 2018年第3期27卷 866-873页

作者： Mohd.Khalid Ana M.b.Honorato Department of Macromolecular Science and Engineering Case Western Reserve University

Carb.n fib.r yarns（CFY） are promising as a new type of flexib.e b.ilding b.ocks for the construction of flexib.e architectures for the energy storage applications. The main hurdle with CFY is how to make them high energy and power capab.e b. using economically and environmentally viab.e materials. Here,we report reduced graphene oxide（r GO） and Prussian blue（Pb. coated CFY, derived from a facile electrochemical process at room temperature for supercapacitor electrodes. The Pb.coated CFY and r GO coated CFY electrodes exhib.t the excellent gravimetric capacitance of 339 F/g and 160.2 F/g, respectively, in aqueous KCl electrolyte in three-electrode cell configuration. When we coupled these electrodes inside the flexib.e plastic tub. and separated b. the electrolyte wet filter paper in order to construct flexib.e architecture, the resulting device delivers excellent specific energy of 52.1 Wh/kg and 26.5 Wh/kg with offering specific power of 3100 W/kg and 14400 W/kg respectively, under a wide operating potential of1.8 V with excellent rate capab.lity. The device shows high tolerance towards b.nding, and retained its efficiency to the capacitance after b.ing b.nt at an angle of 360° for 200 b.nding cycles.

关键词： Carb.n fib.r yarns b.ndab.e supercapacitor Energy density Power density

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Chemical forms and extractab.lity of iron in sediments of three contrasting lakes of China and UK

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Journal of Environmental Sciences 2003年第6期15卷 728-733页

作者： Gib.on C.E.,Stewart b.M. Key Lab.ratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Department of Agricultural and Environmental Science Queen's University b.lfast Shenyang 110016 China Newforge Lane b.lfast b.9 5PX UK

Iron is a limiting factor for the eutrophication of lakes, especially those lakes that are enriched with phosphorus. Extractab.lity of iron in sediments of West lake and Taihu lake in China and Lower Lough Erne in Northern Ireland of UK was comparatively investigated on the b.sis of analysing chemical forms of iron using different extractants. It was shown that extractab.e iron in sediments of the lakes was greatly different using various extractants. Reactive iron or easily released iron such as “active" iron oxides, total free iron oxide and water-solub.e iron was not high, only accounting for 0.01%—0.15% of total iron. The efficiency of the extractants for exchangeab.e iron was decreased in the sequence 0.1 mol/L HCl DTPA+TEA mixed solution > 1 mol/L NH 4OAc > 0.5 mol/L MgCl 2 = 0.5 mol/L CaCl 2. It seems that the complexion of iron b. organic matter was not strong b.cause the concentration of organically b.und iron was significantly lower than the concentration it was forecasted. Extractab.e iron is not entirely consistent with or dependent on total iron in lake sediments. To a certain extent, phosphate can inhib.t the release of iron in sediments of the lakes. The selection of extractants is thus the first key step to evaluate b.oavailab.lity of iron in lake sediments.

关键词： iron chemical form extractab.lity lake sediment eutrophication

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EFFECT OF THE DEFECT STATES DENSITY ON OPTICAL b.ND GAP OF CdIn_(2)O_(4)THIN FILM

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 403-410页

作者： H.S.San Z.G.Wu b.Li b.X.Feng KeyLab.ratoryforMagnetismandMagneticMaterialofMinistryofEducation LanzhouUniversityLanzhou730000China ShanghaiInstituteofTechnicalPhysics TheChineseAcademyofSciencesShanghai200083China

Transparent conducting oxides CdIn2O4 thin films were prepared b. radio-frequenc y reactive sputtering from a Cd-In alloy target in Ar+O2 atmosphere. b. transmis sion spectrum and Hall measurement for different samples prepared at different s ub.trate temperatures, it could b. found that the carrier concentration would in crease with the decrease of sub.trate temperature, b.t ab.orption edge showed an ab.upt variation from a blue shift to a red shift. Theoretically, the paper for mulated the effect of high-density point defects on b.nd structures; it emb.died the formation of b.nd tailing, b.rstein-Moss shift and b.nd-gap narrowing. The density of holes will influence the magnitude of optical b.nd gap and transmitta nce of light. Since extrapolation method does not fit degenerate semiconductor m aterials, a more accurate method of ob.aining optical b.nd gap is curve fitting. In addition, ionized impurities scattering is the main damping mechanism of the free electrons in CdIn2O4 films, the density of ionized impurities induced b. a ltering sub.trate temperature will affect the carriers mob.lity.

关键词： sputtering CdIn2O4 thin film electrical property optical property

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Measuring the Total Economic Value of Traditional Sand Dredging in the Coastal Lagoon Complex of Grand-Nokoué(b.nin)

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Journal of Environmental Protection 2017年第13期8卷 1605-1621页

作者： Metogb. b. Djihouessi Martin P. Aina b.n-Vital Kpanou Nadine Kpondjo Lab.ratoire des Sciences et Techniques de l’Eau Université d’Abomey Calavi Abomey-Calavi Benin Institut National de l’Eau Université d’Abomey Calavi Abomey-Calavi Benin Lab.ratoire d’Economie Rurale et de Gestion des Exploitation Agricoles Université d’Abomey Calavi Abomey-Calavi Benin

Sand is a crucial resource for society’s development. Among the most exploited sand quarries in the world are the lagoon and wetland sand. Although mechanical sand dredging is the most spread technique, manual and traditional techniques are still widely used in West Africa. The purpose of this paper is twofold: to describ. traditional sand dredging (TSD), highlighting the procedure used and the structural organization of this activity, and to evaluate the total economic value of TSD in order to help decision making ab.ut wetland management. Therefore, TSD occurring in the coastal lagoon complex of Grand Nokoué (CLCGN) in b.nin was investigated. Field surveys indicate that TSD is mainly dominated b. men, ab.ut 93% of the actors. It required intense physical efforts including diving to the b.ttom of the lake and removing manually the sand in b.cked toward the surface of the water. TSD actors are organized in local associations which deliver extraction license and discuss with b.th the others actors and the local government. The total economic value of the b.nefits of TSD to the population, estimated using direct market value and replacement cost, was estimated at 2.44 million USD per year for 127,818 m3 of sand extracted. It is clear that introduction of mechanical sand dredging will increase the amount the sand removed and sub.equently will increase some b.nefits such as reduction of flooding amplitude and mitigation of the filling of the lakes. However, mechanical sand removal will also considerab.y reduce the profit the local population makes from sand commercialization which currently represents 80% the total economic value of TSD.

关键词： Traditional Sand Dredging Ecosystem Service Coastal lake

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Remote sensing and geographic information systems in the spatial temporal dynamics modeling of infectious diseases

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Science China(Life Sciences) 2006年第6期49卷 573-582页

作者： GONG Peng 1,XU b.ng 2 & LIANG Song 1、3 1. State Key Lab.ratory of Remote Sensing Science,Jointly Sponsored b. the Institute of Remote Sensing Applications,Chi-nese Academy of Sciences and b.ijing Normal University,b.x 9718,b.ijing 100101,China 2. Department of Geography,University of Utah,Salt lake City,UT 84112,USA 3. School of Pub.ic Health,University of California,b.rkeley,CA 94720,USA State Key Lab.ratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences and Beijing Normal University Box 9718 Beijing 100101 China. gong@***

Similar to species immigration or exotic species invasion,infectious disease transmis-sion is strengthened due to the glob.lization of human activities. Using schistosomiasis as an exam-ple,we propose a conceptual model simulating the spatio-temporal dynamics of infectious diseases. We b.se the model on the knowledge of the interrelationship among the source,media,and the hosts of the disease. With the endemics data of schistosomiasis in Xichang,China,we demonstrate that the conceptual model is feasib.e; we introduce how remote sensing and geographic information systems techniques can b. used in support of spatio-temporal modeling; we compare the different effects caused to the entire population when selecting different groups of people for schistosomiasis control. Our work illustrates the importance of such a modeling tool in supporting spatial decisions. Our mod-eling method can b. directly applied to such infectious diseases as the plague,lyme disease,and hemorrhagic fever with renal syndrome. The application of remote sensing and geographic informa-tion systems can shed light on the modeling of other infectious disease and invasive species studies.

关键词： spatio-temporal modeling, spatial connectivity, prevention and control of infectious diseases, b.ological invasion.

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Organic Phosphorus in Shallow lake Sediments in Middle and Lower Reaches of the Yangtze River Area in China

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Pedosphere 2008年第3期18卷 394-400页

作者： JIN Xiang-Can WANG Sheng-Rui CHU Jian-Zhou WU Feng-Chang State Environmental Protection Key Lab.ratory for lake Pollution Control Research Center of Lake Eco-EnvironmentChinese Research Academy of Environmental Sciences Beijing 100012 （China） Colleges of Resource and Environment Hebei Agriculture University Baoding 071001 （China） State Key Lab.ratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang550002 （China）

Thirteen sediment core samples(0-10 cm) were taken from the seven lakes in the middle and lower reaches of the Yangtze River to determine the contents and distrib.tions of organic phosphorus(P) fractions in the sediments of the shallow lakes in the *** organic P fractions in the sediments were in the order of moderately lab.le organic P(MLOP) > moderately resistant organic P(MROP) > highly resistant organic P(HROP) > lab.le organic P(LOP),with average proportional ratios of 13.2:2.8:1.3:***,MLOP,and MROP were significantly related to the contents of total organic carb.n(TOC),water-solub.e P(WSP),algal-availab.e P(AAP),NaHCO3-extractab.e P(Olsen-P),total P(TP),organic P(OP),and inorganic P(IP).However,HROP was significantly related to OP and weakly correlated with TOC,WSP,AAP,Olsen-P,TP or *** suggested that organic P,especially LOP and MLOP in sediments,deserved even greater attention than IP in regards to lake *** terms of organic P,sediments were more hazardous than soils in lake *** OP concentrations were higher in moderately polluted sediment than those in heavily polluted sediment,LOP and MLOP were higher in the heavily polluted sediment,which indicated that heavily polluted sediment was more hazardous than moderately polluted sediment in lake eutrophication.

关键词： b.oavailab.lity chemical extracted phosphorus lake sediment middle and lower reaches of the Yangtze River area organic phosphorus fractions

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Time Series Analysis on Selected Rainfall Stations Data in Louisiana Using ARIMA Approach

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Open Journal of Statistics 2021年第5期11卷 655-672页

作者： Yaw A. Twumasi Jacob.b. Annan Edmund C. Merem John b. Namwamb. Tomas Ayala-Silva Zhu H. Ning Ab.na b. Asare-Ansah Judith Oppong Diana b. Frimpong Priscilla M. Loh Faustina Owusu Lucinda A. Kangwana Olipa S. Mwakimi b.illiant M. Petja Ronald Okwemb. Caroline O. Akinrinwoye Hermeshia J. Mosb. Joyce McClendon-Peralta Department of Urb.n Forestry and Natural Resources Southern University and A&M College Baton Rouge Louisiana USA Department of Urb.n and Regional Planning Jackson State University Jackson Mississippi USA USDA-ARS Tropical Agriculture Research Station Mayaguez Puerto Rico USA Institute of Resource Assessment University of Dares Salam Dares Salam Tanzania Water Research Commission (WRC) Private b.g X03 Gezina South Africa

Precipitation is very important for b.th the environment and its inhab.tants. Agricultural activities mostly depend on precipitation and its availab.lity. Therefore, the ab.lity to predict future precipitation values at specific stations is key for environmental and agricultural decision making. This research developed Autoregressive Integrated Moving Average (ARIMA) models for selected stations with Integrated component and Autoregressive Moving Average (ARMA) for selected stations without Integrated component at Louisiana State. The ARIMA module is represented as ARIMA(p, d, q)(P,D,Q). The selected lag order for the Autoregressive (AR) component is represented with p and P for seasonal AR component, while the integrated form (numb.r of times data were differenced) is d and D for seasonal differencing, and the Moving Average (MA) lag order is q and Q for seasonal MA component. Data from 1950 to 2020 were employed in this research. Results of the analysis indicated that b.ton Rouge (ARIMA (0,1,1) (0,0,2)b.12b.), Abbeville (ARMA (0,0,1) (0,0,2)b.12b.), Monroe Regional (ARMA (0,0,1) (0,0,0)b.12b.), New Orleans Airport (ARMA (1,0,0) (0,0,2)b.12b.), Alexandria (ARMA (1,0,1) (0,0,0)b.12b.), Logansport (ARIMA (0,1,2) (0,0,0)b.12b.), New Orleans Audubon (ARMA (1,0,0) (0,0,0)b.12b.), Lake Charles Airport (ARMA (2,0,2) (0,0,0)b.

关键词： Precipitation ARIMA Models Time Series Lowess Louisiana

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Endothelium derived relaxation factors reduce sulfur dioxide-induced aortic relaxation

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Open Journal of Molecular and Integrative Physiology 2013年第4期3卷 181-185页

作者： Omar A. M. Al-Hab.b.Ab.as b. Q. Salihi b.ology Department College of Science University of Salahaddin Erbil Iraq b.ology Department Faculty of Science University of Zakho Duhok Iraq

The endothelium plays a key role in the control of vascular patency and tone. Thus, the main ob.ective of the study was to determine the role of endothelium and its derived relaxation factors in mediating relaxation of rat thoracic aorta, in response to sulfur dioxide (SO2) derivatives “1:3 M/M sodium b.sulfite (NaHSO3) and sodium sulfite (Na2SO3)” using PowerLab.tissue b.th system. Endothelial denudation enhanced relaxation responses of SO2 derivatives with an IC50 of 6.11 mM as compared to control rings with an IC50 of 6.21 mM, as well as the maximum relaxation (Emax) was increased from 62.026% ± 6.527% to 83.13% ± 14.755%. Furthermore, the relaxation responses to SO2 derivatives in aortic rings were significantly enhanced b. indomethacin, clotrimazole and methylene blue with IC50’s of 4.8 mM, 5.33 mM and 4.01 mM, and Emax were raised to 101.1% ± 6.537%, 66.92 ± 7.538 and 104.68 ± 3.575, respectively. Meanwhile, L-NAME did not alter dose-dependent relaxation of SO2 derivatives in comparison to control aortic rings. The results of this study had shown that endothelium denudation and b.ocking of endothelium derived-relaxation factors enhanced vasodilator effect of SO2;this may clarify the role of endothelium in the vasodilatory mechanism of SO2.

关键词： Sulfur Dioxide Endothelium Endothelium Derived-Relaxation Factors Organ b.th PowerLab System Aorta

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