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The Role of the Halted Baroclinic Mode at the Central Equatorial Pacific in El nifn Event

Advances in Atmospheric Sciences 2006年第1期23卷 45-53页

作者：孙即霖 peter CHU 刘秦玉 Physical Oceanography Laboratory and Ocean-Atmosphere Interaction and Climate Laboratory Ocean University of ChinaQingdao 266003 Department of Oceanography Naval Postgraduate SchoolMontereyU.S.A.

The role of halted ＂baroclinic modes＂ in the central equatorial Pacific is analyzed. It is found that dominant anomaly signals corresponding to ＂baroclinic modes＂ occur in the upper layer of the equatorial Pacific, in a two-and-a-half layer oceanic model, in assimilated results of a simple OGCM and in the ADCP observation of TAO. A second ＂baroclinic mode＂ is halted in the central equatorial Pacific corresponding to a positive SST anomaly while the first ＂baroclinic mode＂ propagates eastwards in the eastern equatorial Pacific. The role of the halted second ＂baroclinic mode＂ in the central equatorial Pacific is explained by a staged ocean-atmosphere interaction mechanism in the formation of El nifio： the westerly bursts in boreal winter over the western equatorial Pacific generate the halted second ＂baroclinic mode＂ in the central equatorial Pacific, leading to the increase of heat content and temperature in the upper layer of the central Pacific which induces the shift of convection from over the western equatorial Pacific to the central equatorial Pacific; another wider, westerly anomaly burst is induced over the western region of convection above the central equatorial Pacific and the westerly anomaly burst generates the first ＂baroclinic mode＂ propagating to the eastern equatorial Pacific, resulting in a warm event in the eastern equatorial Pacific. The mechanism presented in this paper reveals that the central equatorial Pacific is a key region in detecting the possibility of EnSO and, by analyzing TAO observation data of ocean currents and temperature in the central equatorial Pacific, in predicting the coming of an El nino several months ahead.

关键词： halted baroclinic mode central equatorial Pacific staged atmosphere-ocean interaction mechanism El nino

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Obstruction Theory and Coincidences in Positive Codimension

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Acta Mathematica Sinica,English Series 2006年第5期22卷 1591-1602页

作者： Daciberg GOnCALVES Jerzy JEZIERSKI peter WOnG Departamento de Matemática-Instituto de Matemdtica e Estatística-Universidade de Sǎo Paulo Caixa Postal 66.281-CEP 05311-970 Sǎo Paulo-SP Brasil Department of Mathematics University of Agriculture Nowoursynowska 166 02766 Warszawa Poland Department of Mathematics Bates College Lewiston ME 04240 USA

Let f, g ： X→Y be two maps between closed manifolds with dim X ≥ dim Y = n ≥ 3. We study the primary obstruction on（f, g） to deforming f and g to be coincidence free on the n-th skeleton of X. We give examples f... 详细信息

关键词： nielsen number Reidemeister number coincidence theory obstruction theory

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Constraints on Camel Meat and Milk Marketing and Strategies for Its Improvement in northern Kenya

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Journal of Agricultural Science and Technology(A) 2011年第5期1卷 703-712页

作者： S. G. Kuria A. Omore I. n. Thendiu D. M. mwangi A. B. ngaanga S. Kaitibie Kenya Agricultural Research Institute P.O. Box 147-60500 Marsabit Kenya International Livestock Research Institute Nairobi Campus Kenya Ministry of Livestock Development Headquarters HillPlaza Nairobi Kenya Kenya Agricultural Research Institute P.O. Box 57811-00200 Nairobi Kenya Kenya CamelAssociation HillPlaza Nairobi Kenya

A survey to identify constraints and design strategies to improve the camel milk and meat value chains was conducted in northern Kenya using Participatory Integrated Community Development （PICD）, Focus Group Discussions （FGD）, among other methods. In a second step, field testing of an intervention on milk and meat hygiene was carried out at household level. Survey results indicated that about 50% of marketable camel milk was not sold, 30% of marketed camel milk per annum was sold in sour state at US$ 0.13 lower that the price of a litre of fresh milk while processed meat got spoiled along the chain. Annual economic losses associated with milk spoilage were estimated at US$ 961,538.5. Preliminary findings of the field testing indicated that an additional 3 million litres of camel milk was sold in fresh state, giving an annual saving of US$ 384,615.4. Increased profitability of up to 60% compared to 30% before the intervention was reported among nyirinyiri processors. In conclusion, economic potential of the camel could be fully exploited by facilitating adoption of interventions such as hygiene, among others at all levels of the camel milk and meat value chains.

关键词： Value chains camel products economic potential pastoralists arid Kenya.

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Phase stability and mechanical properties of wire+arc additively manufactured H13 tool steel at elevated temperatures

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Journal of Materials Science & Technology 2021年第8期67卷 80-94页

作者： A.n.M.Tanvir Md.R.U.A hsan Gijeong Seo Brian Bates Chanho Lee peter K.Liaw Mark noakese Andrzej nycz Changwook Ji Duck Bong Kim Department of Mechanical Engineering Tennessee Technological UniversityCookevilleTN 38505USA Department of Manufacturing and Engineering Technology Tennessee Technological UniversityCookevilleTN 38505USA Center for Manufacturing Research Tennessee Technological UniversityCookevilleTN 38505USA Department of Materials Science and Engineering University of TennesseeKnoxvilleTN 37996USA Manufacturing Demonstration Facility Oak Ridge National LaboratoryOak RidgeTN 37830USA Advanced Forming Process R&D Group Korea Institute of Industrial TechnologyUlsan 44413Republic of Korea

Wire+arc additive manufacturing(WAAM)is considered an innovative technology that can change the manufacturing landscape in the near *** offers the benefits of inexpensive initial system setup and a high deposition rate for fabricating medium-and large-sized parts such as die-casting *** this study,AISI H13 tool steel,a popular die-casting tool metal,is manufactured by cold metal transfer(CMT)-based WAAM and is then comprehensively analyzed for its microstructural and mechanical ***-dependent phase combinations are observed,which could be explained by nonequilibrium thermal cycles that resulted from the layer-by-layer stacking mechanism used in *** addition,remelting and reheating of the layers reduces welding anomalies(e.g.,pores and voids).The metallurgical characteristics of the H13 strongly correlate with the mechanical *** combinations of phases at different locations of the additively manufactured part exhibit a periodic microhardness ***,Retained Austenite,Ferrite,and Carbide phases are found in combination at different locations of the part based on the part’s temperature distribution during additive ***,the tensile properties at elevated temperatures(23℃,300℃,and 600℃)are comparable to those from other WAAM and additive manufacturing(AM)*** X-ray diffraction results verify that the microstructural stability of the fabricated parts at high temperatures would allow them to be used in high temperatures.

关键词： Tool steel Martensitic steel Wire+arc additive manufacturing(WAAM) High temperature tensile test High temperature XRD

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Reductive dechlorination of polychlorinated biphenyls is coupled to nitrogen fixation by a legume-rhizobium symbiosis

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Science China Earth Sciences 2018年第3期61卷 285-291页

作者： Chen TU Yongming LUO Ying TEnG peter CHRISTIE Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone ResearchChinese Academy of Sciences Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of Sciences

Chlorinated persistent organic pollutants, including polychlorinated biphenyls （PCBs）, represent a particularly serious environmental problem and human health risk worldwide. Leguminous plants and their symbiotic bacteria （rhizobia） are important components of the biogeochemical cycling of nitrogen in both agricultural and natural ecosystems. However, there have been relatively few detailed studies of the remediation of PCB-contaminated soils by legume-rhizobia symbionts. Here we report for the first time evidence of the reductive dechlorination of 2,4,4＇-trichlorobiphenyl （PCB 28） by an alfalfa-rhizobium nitrogen fixing symbiont. Alfalfa （Medicago sativa L.） inoculated with wild-type Sinorhizobiurn meliloti had significantly larger biomass and PCB 28 accumulation than alfalfa inoculated with the nitrogenase negative mutant rhizobium SmY. Dechlorination products of PCB 28, 2,4＇-dichlorobiphenyl （PCB 8）, and the emission of chloride ion （C1-） were also found to decrease significantly in the ineffective nodules infected by the mutant strain SmY. We therefore hypothesize that n2-fixation by the legume-rhizobium symbiont is coupled with the reductive dechlorination of PCBs within the nodules. The combination of these two processes is of great importance to the biogeochemical cycling and bioremediation of organochlorine pollutants in terrestrial ecosystems.

关键词： Biogeochemical cycling Legume-rhizobia symbiosis Microbe-assisted phytoremediation nitrogen fixation,Polychlorinated biphenyls Soil pollution and remediation Reductive dechlorination

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Proteomic response of wheat embryos to fosthiazate stress in a protected vegetable soil

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Journal of Environmental Sciences 2012年第10期24卷 1843-1853页

作者： Chunyan Yin Ying Teng Yongming Luo peter Christie Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Graduate University of Chinese Academy of Sciences Beijing 100049China Yantai Institute of Coastal Zone Research Chinese Academy of SciencesYantai 264003China Agri-Environment Branch Agri-Food and Biosciences InstituteNewforge LaneBelfast BT95PXUnited Kingdom

A proteomic analysis of wheat defense response induced by the widely used organophosphorus nematicide fosthiazate is reported. Seed germination and two-dimensional gel electrophoresis （2-DE） experiments were performed using a Chinese wheat cultivar, Zhenmai no. 5. Root and shoot elongation decreased but thiobarbituric acid reactive substances （TBARS） content in embryos increased with increasing pesticide concentration. More than 1000 protein spots were reprodueibly detected in each silver-stained gel. Thirty-seven protein spots with at least 2-fold changes were identified using MALDI-TOF MS/MS analysis. Of these, 24 spots were up-regulated and 13 were down-regulated. Proteins identified included some well-known classical stress responsive proteins under abiotic or biotic stresses as well as some unusual responsive proteins. Ten responsive proteins were reported for the first time at the proteomic level, including fatty acyl CoA reductase, dihydrodipicolinate synthase, DEAD-box ATPase-RnA-helicase, fimbriata-like protein, waxy B 1, rust resistance kinase Lrl0, putative In2.1 protein, retinoblastoma-related protein 1, pollen allergen-like protein and S-adenosyl-L- methionine：phosphoethanolamine n-methyltransferase. The proteins identified were involved in several processes such as metabolism, defense/detoxification, cell structure/ceU growth, signal transduction]transcription, photosynthesis and energy. Seven candidate proteins were further analyzed at the mRnA level by RT-PCR to compare transcript and protein accumulation patterns, revealing that not all the genes were correlated well with the protein level. Identification of these responsive proteins may provide new insight into the molecular basis of the fosthiazate-stress response in the early developmental stages of plants and may be useful in stress monitoring or stress-tolerant crop breeding for environmentally friendly agricultural production.

关键词： fosthiazate proteomic wheat embryo stress response biological indicator

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Magnesite and talc origin in the sequence of geodynamic events in Veporicum, Inner Western Carpathians, Slovakia

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岩石学报 2004年第4期20卷 837-854页

作者： Zoltán nMETH Walter PROCHASKA Martin RADVAnEC Martin KOV■IK Ján MADARAS peter KOD■RA L'ubomír HRA■KO Geological Survey of Slovak Republic Jesenskeho 8 SK-040 01 Kosice Slovak Republic Department of Geological Sciences University of Leoben A-8700 Leoben Austria Geological Survey of Slovak Republic Marku ovsk cesta 1 SK-052 01 Spisska Nova Ves Slovak Republic Geological Survey of Slovak Republic Mlynsk dolina 1 SK-817 04 Bratislava Slovak Republic

This paper summarizes recent data about magnesite and talc genesis in Carboniferous host rocks of Western Carpathians (Slovakia) , which occur in two distinct belts in tectonic superunit Veporicum and its contact zone with Gemericum. The northern Sinec magnesite and talc belt (with main deposits Kokava, Sinec, Samo, Hnust'a-Mutnik) contains economic accummulation of magnesite and talc, while in the southern Ochtina belt ( main deposits in Dubrava massif-Dubrava, Mikova, Jedl'ovec; Lubenik, Ochtina, Kosice-Bankov, Banisko, Medvedia) the magnesite is *** magnesite genesis by successive replacement of Carboniferous calcite to dolomite and magnesite during metamorphic process Ml (northern belt 280-400℃; , southern belt 370-420℃: ; Radvanec & Prochaska, 2001; Kodera & Radvanec, 2002) , being supplied by Mg from Permoscythian evaporitic bittern brines, relates to Variscan post-collisional (post-VD) evolution. The extensional tectonics and the high heat flow facilitated the generation of a hydrothermal *** time-separated later metamorphic and sourcely different fluid flow event (M2; 1. c. ) produced talc. Tectonic, microtectonic, metamorphic and geochronological data relate the talc origin with the Alpine Upper Cretaceous (88-84 Ma; Maluski in Kovacik et al. , 1996) tectonothermal event AD2. This event, being the consequence of Alpine collisional ( AD1 ) crustal thickening and metamorphic core complex origin, meant regional extension and pervasive fluid flow of open system in crustal discontinuities. This process was prominent in the northern belt ( Sinec shear zone) located more closely to Veporic thermal dome, while towards its peripheral parts (southern Ochtina belt) the M2 metamorphic process and steatitization gradually *** from Sinec shear zone (being the prominent AD2 -AD3 structure of northern Sinec belt) , where the dolomite/magnesite lenses (replacement in M1) and their accompanying lithology were in AD1 sandwitched between more com

关键词： Magnesite and talc genesis Geodynamic evolution Shear zones Microstructures Fluid inclusions WesternCarpathians

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Application of Water Quality Model QUAL2K to Model the Dispersion of Pollutants in River ndarugu, Kenya

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Computational Water, Energy, and Environmental Engineering 2014年第4期3卷 162-169页

作者： Letensie Tseggai Hadgu Maurice Omondi nyadawa John Kimani mwangi Purity Muthoni Kibetu Beraki Bahre Mehari Department of Civil Construction and Environmental Engineering Jomo Kenyatta University of Agriculture and Technology Nairobi Kenya Jaramogi Oginga Odinga University of Science and Technology Bondo Kenya

ndarugu River, Kenya, during its course through the different agricultural and industrial areas of Gatundu, Gachororo and Juja farms, receives untreated industrial, domestic and agricultural waste of point source discharges from coffee and tea factories. During wet season the water is also polluted by non-point (diffuse) sources created by runoff carrying soil, fertilizer and pesticide residues from the catchment area. This study involved the calibration of water quality model QUAL2K to predict the water quality of this segment of the river. The model was calibrated and validated for flow discharge (Q), temperature (T°), flow velocity (V), biochemical oxygen demand (BOD5), dissolved oxygen (DO) and nitrate (nO3-n), using data collected and analyzed during field and laboratory measurements done in July and november-December 2013. The model was then used in simulation and its performance was evaluated using statistical criteria based on correlation coefficient (R2) and standard errors (SE) between the observed and simulated data. The model reflected the field data quite well with minor exceptions. In spite of these minor differences between the measured and simulated data set at some points, the calibration and validation results are acceptable especially for developing countries where the financial resources for frequent monitoring works and higher accuracy data analysis are very limited. The water is being polluted by the human activities in the catchment. There is need for proper control of wastewater by various techniques, and preliminary treatment of waste discharges prior to effluent disposal. Management of the watershed is necessary so as to protect the river from the adverse impacts of agricultural activities and save it from further deterioration.

关键词： BOD5 DO QUAL2K River Pollution Water Quality Modeling

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Effect of silver-nanoparticles generated in poly(vinyl alcohol)membranes on ethanol dehydration via pervaporation

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Chinese Journal of Chemical Engineering 2019年第7期27卷 1595-1607页

作者： Asmaa Selim Andras Jozsef Toth Daniel Fozer Eniko Haaz nóra Valentínyi Tibor nagy Orsolya Keri Lászlo Péter Bakos Imre Miklós Szilágyi peter Mizsey Department of Chemical and Environmental Process Engineering Budapest University of Technology and Economics1111 BudapestHungary Chemical Engineering Department National Research Centre12611 GizaEgypt Department of Inorganic and Analytical Chemistry Budapest University of Technology and Economics1111 BudapestHungary Department of Fine Chemicals and Environmental Technology University of Miskolc3515 MiskolcHungary

Pervaporation is an important membrane separation method of chemical *** this work,silver-nanoparticles-poly(vinyl alcohol)nanocomposite membranes(AgnPs-PVA)are produced for the sake of improving its potentials for pervaporation of ethanol–water mixture so that the usual opposite trend between membrane selectivity and permeation can be *** nanocomposite membranes are fabricated from an aqueous solution of poly(vinyl alcohol)with silver nanoparticles via the in-situ generation technique in the absence of any reducing *** generation of the nano size silver is measured by the UV–vis spectrum showing a single peak at 419 nm due to the plasmonic effect of silver *** nanocomposite AgnPs-PVA membranes are characterized using scanning electron microscope(SEM),Fourier-transform infrared(FT-IR)spectroscopy,X-ray diffraction and thermogravimetric analysis(TGA).The pervaporation tests of our new AgnPs-PVA membranes show good results since at a higher temperature and higher ethanol concentration in the feed,the prepared membranes are highly permeable for the water having stable selectivity values and therefore our membranes show better performance compared to that of the other PVA-based nanocomposite membranes.

关键词： Silver nanoparticle Poly(vinyl alcohol)nanocomposite membrane Hydrophilicity Swelling degree Pervaporation

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Phylogenetic Relationships of 3/3 and 2/2 Hemoglobins in Archaeplastida Genomes to Bacterial and Other Eukaryote Hemoglobins

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Molecular Plant 2011年第1期4卷 42-58页

作者： Serge n. Vinogradov Ivan Fernandez David Hoogewijs Rail Arredondo-peter Department of Biochemistry and Molecular Biology Wayne State University School of Medicine Detroit MI 48201 USA Laboratorio de Biofisica y Biologia Molecular Facultad de Ciencias Universidad Autonoma del Estado de Morelos 62210 Cuernavaca Morelos Mexico Institute of Physiology and Zurich Center for Integrative Human Physiology (ZIHP) University of Zurich Zurich Switzerland

Land plants and algae form a supergroup, the Archaeplastida, believed to be monophyletic. We report the results of an analysis of the phylogeny of putative globins in the currently available genomes to bacterial and other eu- karyote hemoglobins （Hbs）. Archaeplastida genomes have 3/3 and 2/2 Hbs, with the land plant genomes having group 2 2/ 2 Hbs, except for the unexpected occurrence of two group 1 2/2 Hbs in Ricinus communis. Bayesian analysis shows that plant 3/3 Hbs are related to vertebrate neuroglobins and bacterial flavohemoglobins （FHbs）. We sought to define the bacterial groups, whose ancestors shared the precursors of Archaeplastida Hbs, via Bayesian and neighbor-joining anal- yses based on COBALTalignment of representative sets of bacterial 3/3 FHb-like globins and group I and 2 2/2 Hbs with the corresponding Archaeplastida Hbs. The results suggest that the Archaeplastida 3/3 and group 1 2/2 Hbs could have orig- inated from the horizontal gene transfers （HGTs） that accompanied the two generally accepted endosymbioses of a pro- teobacterium and a cyanobacterium with a eukaryote ancestor. In contrast, the origin of the group 2 212 Hbs unexpectedly appears to involve HGT from a bacterium ancestral to Chloroflexi, Deinococcales, Bacilli, and Actinomycetes. Furthermore, although intron positions and phases are mostly conserved among the land plant 3/3 and 2/2 globin genes, introns are absent in the algal 3/3 genes and intron positions and phases are highly variable in their 2/2 genes. Thus, introns are irrelevant to globin evolution in Archaeplastida.

关键词： Algae Archaeplastida evolution hemoglobin land plants truncated Hbs

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