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New homotopy analysis transform method for solving the discontinued problems arising in nanotechnology

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Chinese Physics B 2013年第11期22卷 135-139页

作者： m.m.Khader Sunil Kumar S.Abbasbandy Department of mathematics and Statistics College of Science Al-Imam Mohammed Ibn Saud Islamic University (IMSIU) Department of mathematics Faculty of Science Benha University Department of mathematics National Institute of Technology Department of mathematics Imam Khomeini International University

We present a new reliable analytical study for solving the discontinued problems arising in nanotechnology. Such problems are presented as nonlinear differential-difference equations. The proposed method is based on the Laplace trans- form with the homotopy analysis method （HAm）. This method is a powerful tool for solving a large amount of problems. This technique provides a series of functions which may converge to the exact solution of the problem. A good agreement between the obtained solution and some well-known results is obtained.

关键词： discretized mKdV lattice equation nonlinear differential-difference equations Laplace transform,homotopy analysis transform method

Immediate and long-term effects of invasive plant species on soil characteristics

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Soil Ecology Letters 2022年第3期4卷 276-288页

作者： Irene m.Unger Robert j.Kremer Kristen S.Veum Keith W.Goyne Department of Biology and Chemistry Baker UniversityP.O.Box 65Baldwin CityKS 66006USA School of Natural Resources University of missouri 302 ABNR Bldg.ColumbiaMO 65211USA USDA-ARS Cropping Systems and Water Quality UnitUniversity of Missouri302 ABNR Bldg.ColumbiaMO 65211USA Department of Forest Resources and Environmental Conservation Virginia Tech324 Cheatham HallBlacksburgVA 24061USA

Invasive plant species may alter soil characteristics or interact with the soil microbial community resulting in a competitive *** objectives were to determine:i)if invasive plant species alter soil properties;and ii)the long-term effects of invasive plant species on soil properties and subsequent implications on ecological restoration *** focused on Lespedeza cuneata,a plant that may be *** samples were collected from four locations in Central missouri,USA:an old-field with abundant ***,two reconstructed sites,and a remnant prairie that has never been *** health indictors were used to characterize soil properties at these *** every soil property differed significantly between the unplowed prairie reference site and the other three *** reconstructed sites,however,generally did not differ from the invaded *** results indicate that the reconstructed prairies are not fully *** above-ground traits,such as the plant community structure,appear similar to the prairie,the soil microbial community structure still resembles that of an invaded old-field *** results indicate that more time may be needed before soil microbial populations fully recover after invasive plant removal.

关键词： Sericea lespedeza Legacy effects Soil microorganisms

Anisotropic NdFeB magnet Fabricated by Single Stroke Hot Deformation

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journal of materials Science & Technology 2000年第2期16卷 129-130页

作者： Y.Li (Chungnam National University, Taejon, Korea) Y.B.Kim (Korea Research Institute of Standards and Science, Taejon, Korea) m.j.Kim, m.S.Song, j.H.Yang, T.K.Kim and C.O.Kim (Chungnam National University, Taejon, Korea) Chungnam National University Taejon South Korea Korea Research Institute of Standards and Science Taejon South Korea

The general hot deformation process consists of two steps, hot pressing and die-upsetting in order to obtain the anisotropic NdFeB magnet. This is the first report that the high anisotropy NdFeB magnets can be fabricated by single stroke hot deforming the isotropic magnet. The magnetic properties of those materials are: coercivity iHc ～11 kOe, remanence Br ～12 kG, and the maximum energy product (BH)max ～28 ***.

关键词： NdFeB Anisotropic NdFeB magnet Fabricated by Single Stroke Hot Deformation

Identification of Iron Oxides Qualitatively/Quantitatively Formed during the High Temperature Oxidation of Superalloys in Air and Steam Environments

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journal of materials Science & Technology 2009年第4期25卷 479-482页

作者： m. Siddique N. Hussain m. Shafi Physics Division PINSTECH materials Division PINSTECH

mossbauer spectroscopy has been used to study the morphology of iron oxides formed during the oxidation of superalloys, such as SS-304L （1.4306S）, Incoloy-800H, Incoloy-825, UBHA-25L, Sanicro-28 and Inconel-690, at 1200℃ exposed in air and steam environments for 400 h. The basic aim was to identify and compare the iron oxides qualitatively and quantitatively, formed during the oxidation of these alloys in two environments. The behaviour of alloy UBHA-25L in high temperature oxidation in both environments indicates that it has good oxidation resistance especially in steam, whereas Sanicro-28 has excellent corrosion resistance in steam environment. In air oxidation of Inconel-690 no iron oxide, with established mossbauer parameters, was detected.

关键词： Superalloys mossbauer spectroscopy Oxidation Corrosion products

Six novel species of Fusarium from natural ecosystems in Australia

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Fungal Diversity 2016年第2期77卷 349-366页

作者： m.H.Laurence j.L.Walsh L.A.Shuttleworth D.m.Robinson R.m.johansen T.Petrovic T.T.H.Vu L.W.Burgess B.A.Summerell E.C.Y.Liew The Royal Botanic Gardens and Domain Trust Mrs Macquaries RdSydneyNSW 2000Australia Faculty of Agriculture and Environment The University of SydneyEveleighNSW 2015Australia

Six new species of Fusarium associated with soil and plant hosts from ecosystems of minimal anthropogenic disturbance in Australia are *** coicis from Coix gasteenii,*** from Xanthorrhoea glauca,*** from soil and mangifera indica,*** from soil,*** from Sorghum interjectum and *** from soil,Triodia microstachya,Sorghum interjectum and Sorghum *** and phylogenetic analysis of EF-1α,RPB1 and RPB2 sequence data were used to delineate species *** new species were phylogenetically distributed in the Fusarium sambucinum,***,and *** species complexes,and two novel species *** six new species have particular phylogeographic significance as not only do they provide further insight into the geographic patterns of Fusarium evolution but also challenge current phylogeographic hypotheses.

关键词： Species diversity Endophyte Phylogenetics mycoflora Phylogeography

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深海环境海洋生态系统监测与修复新技术

Engineering 2024年第3期34卷 195-211页

作者： jacopo Aguzzi Laurenz Thomsen Sascha Flögel Nathan j.Robinson Giacomo Picardi Damianos Chatzievangelou Nixon Bahamon Sergio Stefanni jordi Grinyó Emanuela Fanelli Cinzia Corinaldesi joaquin Del Rio Fernandez marcello Calisti Furu mienis Elias Chatzidouros Corrado Costa Simona Violino michael Tangherlini Roberto Danovaro Instituto de Ciencias del mar(ICm-CSIC) Barcelona 08003Spain Stazione Zoologica Anton Dohrn Naples 80121Italy University of Gothenburg Göteborg 40530Sweden GEOmAR Helmholtz Centre for Ocean Research Kiel 24148Germany Fundación Oceanogràfic de la Comunitat Valenciana Valencia 46013Spain Royal Netherlands Institute for Sea Research(NIOZ) Den Burg Texel 1790 ABNetherlands Polytechnic University of marche(UNIVPm) Ancona 60131Italy SARTI-mAR of the Universitat Politecnica de Catalunya(UPC) Vilanova i la Geltrú08800Spain Lincoln Institute for Agri-food Technology University of LincolnLincoln LN22LGUK Engitec Systems International Limited Limassol 3083Cyprus Consiglio per la Ricerca in Agricoltura e L’analisi Dell’economia Agraria(CREA) Centro di Ricerca Ingegneria e Trasformazioni AgroalimentariMonterotondo 00015Italy

The United Nations(UN)’s call for a decade of“ecosystem restoration”was prompted by the need to address the extensive impact of anthropogenic activities on natural *** ecosystem restoration is increasingly necessary due to increasing habitat degredation in deep waters(>200 m depth).At these depths,which are far beyond those accessible by divers,only established and emerging robotic platforms such as remotely operated vehicles(ROVs),autonomous underwater vehicles(AUVs),landers,and crawlers can operate through manipulators and multiparametric sensor arrays(e.g.,optoacoustic imaging,omics,and environmental probes).The use of advanced technologies for deep-sea ecosystem restoration can provide:①high-resolution three-dimensional(3D)imaging and acoustic mapping of substrates and key taxa,②physical manipulation of substrates and key taxa,③real-time supervision of remote operations and long-term ecological monitoring,and④the potential to work ***,we describe how robotic platforms with in situ manipulation capabilities and payloads of innovative sensors could autonomously conduct active restoration and monitoring across large spatial *** expect that these devices will be particularly useful in deep-sea habitats,such as①reef-building cold-water corals,②soft-bottom bamboo corals,and③soft-bottom fishery resources that have already been damaged by offshore industries(i.e.,fishing and oil/gas).

关键词： Ecosystem restoration Robotic manipulation Acoustic tracking Fishery resources Artificial reefs

Environmental Characterization of Periphyton Community

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journal of Ocean University of China 2006年第4期5卷 305-310页

作者： Y. m. jo j. m. Oh j.G.Yoo Department of Environmental Science & Engineering Center for Environmental Studies Kyunghee University Kyunggido 449-701 Kore Department of Chemical Engineering Hanseo University Chungcheongnamdo Korea

The present paper deals with the behavior of the Attached microbial Community (AmC) for water self-purification at different riverbeds in a typical local river. The study quantitatively investigated the problem starting with in-situ sampling. It was found that more biomass of AmC was at riffles with wider distribution than in pools. High current velocity (HCV) plays a negative role at the initial stage of attachment on the riverbed, but HCV aids the community proliferation after stable attachment. External disturbances such as rainfalls and discharges from dams or reservoirs would detach the periphyton depending on the intensity of turbulence in water. However, it was discovered that the flock of periphyton could be restored very quickly because it was not completely removed. Thus, in order to enhance self-purification by periphyton, a suitable configuration of the riverbed must be constructed, and occasional appropriate repair along the channels would improve the decontamination of the river.

关键词： periphyton riffle pool riverbed self-purification

Estimation of drag forces caused by natural woody vegetation of different scales

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journal of Hydrodynamics 2014年第4期26卷 608-623页

作者： jALONEN johanna jRVEL juha Department of Civil and Environmental Engineering Aalto University

To reliably estimate water levels and velocities in vegetated rivers and floodplains, flow resistance models based on physical plant properties are advantageous. The purpose of this study is （1） to assess the suitable parameterization of woody riparian vegetation in estimating the drag forces, （2） to address the effect of plant scale on the drag estimates and reconfiguration, and （3） to evaluate the applicability of three recently developed flow resistance models. Experiments on four tree species in a towing tank together with detailed characterization of tree properties were carried out to establish a novel dataset. Despite the variability in the tree height （0.9 m-3.4 m）, the stem, leaf and total areas proved to be suitable characteristic dimensions for estimating the flow resistance at different scales. Evaluations with independent data revealed that the tested models produced reasonable results. The performance of the models was controlled by the parameter values used rather than the model structure or the plant scale.

关键词： drag force flow resistance woody vegetation modelling

On Noncommutative Sinh-Gordon Equation

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Chinese Physics Letters 2005年第5期22卷 1076-1078页

作者： U.Saleem m.Siddiq m.Hassan DepartmentofPhysics UniversityofthePunjabQuaid-e-AzamCampusLahore-54590Pakistan

We give a noncommutative extension of a sinh–Gordon equation. We generalize a linear system and Lax representation of the sinh–Gordon equation in noncommutative space. This generalization gives a noncommutative vers... 详细信息

关键词： Linear systems