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Competition for shelter between four invasive gobiids and two native benthic fish species

Current Zoology 2011年第6期57卷 844-851页

作者： n. VAn KESSEL M. DOrEnBOSCH M.r.M. DE BOEr r.S.E.W. LEUVEn g. VAn DEr VELDE radboud University nijmegen Institute for Water and Wetland Research Department of Animal Ecology and Ecophysiology EO. Box 9010 6500 GL Nijmegen The Netherlands radboud University nijmegen Institute for Water and Wetland Research Department of Environmental Science P.O. Box 9010 6500 GL Nijmegen The Netherlands natuurbalans - Limes Divergens P.O. Box 31070 6503 CB Nijmegen The Netherlands netherlands Institute of Ecology （nIOO - KnAW） EO. Box 50 6700 AB Wageningen The Netherlands netherlands Centre for Biodiversity naturalis EO. Box 9517 2300 RA Leiden The Netherlands

recent invasions by non-native gobiid fish species that are ongoing in the Western European rivers rhine and Meuse, will lead to interactions with native benthic fish species. Since both non-native gobiids and native benthic species are bottom dwelling species with a preference for shelter during at least part of their life cycle, it is likely that competition for shelter will occur between these non-native and native species when shelter is a limiting factor. To investigate the importance of this mecha- nism for species replacements, various habitat choice experiments were conducted between two common native benthic fish spe- cies （Cottus perifretum and Barbatula barbatula） and four invasive non-native gobiid species （Proterorhinus semilunaris, neogo- bius melanostomus, n. kessleri and n. fluviatilis）. The first series of single specimen experiments determined the habitat choice of each individual fish species. In a second series of competition experiments, shifts in habitat choice in comparison with the previ- ously observed habitat choice, were determined when a native benthic fish species co-occurred with non-native gobiid species. native C. perifretum displayed a significant shift in habitat choice in co-occurrence with the gobiids n. kessleri or P. semilunaris. C. perifretum was outcompeted and moved from the available shelter place to less preferred habitat types. During the competition experiments no change in habitat choice of B. barbatula was shown. Our study therefore suggests that competition for shelter is likely to occur in rivers invaded by n. kessleri and P. semilunaris at sites where shelter is limiting

关键词： Bullhead Exotic species Habitat choice Invasive gobies rivers rhine and Meuse Stone loach

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Exclusive semileptonic decays of D and Ds mesons in the covariant confining quark model

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Frontiers of physics 2019年第6期14卷 103-132页

作者： M.A.Ivanov J.g.Korner J.n.Pandya P.Santorelli n.r.Soni C.T.Tran Bogoliubov Laboratory of Theoretical Physics Joint Institute for Nuclear Research141980 DubnaRussia PrISMA Cluster of Excellence Institut für PhysikJohannes Gutenberg-UniversitatD-55099 MainzGermany Applied Physics Department Faculty of Technology and EngineeringThe Maharaja Sayajirao University of BarodaVadodara 390001GujaratIndia Dipartimento di Fisica"E.Pancini" Universitàdi Napoli FedericoⅡComplesso Universitario di Monte S.AngeloVia CintiaEdificio 680126 NapoliItaly Istituto nazionale di Fisica nucleare Sezione di Napoli80126 NapoliItaly

recently,the BESⅢcollaboration has reported numerous measurements of various D(s)meson semileptonic decays with significantly improved *** with similar studies carried out at BABAr,Belle,and CLEO,new windows to a better understanding of weak and strong interactions in the charm sector have been *** light of new experimental data,we review the theoretical description and predictions for the semileptonic decays of D(s)to a pseudoscalar or a vector *** review is essentially an extended discussion of our recently published results obtained in the framework of the covariant confining quark model.

关键词： covariant quark model semileptonic decay charmed meson form factor angular distribution

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Artificial neural network approach for prediction of stress–strain curve of near b titanium alloy

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rare Metals 2014年第3期33卷 249-257页

作者： Srinivasu gangi Setti r.n.rao Mechanical Engineering National Institute of Technology

In the present study, artificial neural network（Ann） approach was used to predict the stress-strain curve of near beta titanium alloy as a function of volume fractions of a and b. This approach is to develop the best possible combination or neural network（nn） to predict the stress-strain curve. In order to achieve this, three different nn architectures（feed-forward back-propagation network,cascade-forward back-propagation network, and layer recurrent network）, three different transfer functions（purelin, Log-Sigmoid, and Tan-Sigmoid）, number of hidden layers（1 and 2）, number of neurons in the hidden layer（s）,and different training algorithms were employed. Ann training modules, the load in terms of strain, and volume fraction of a are the inputs and the stress as an *** system was trained using the prepared training set（a,16 % a, 40 % a, and b stress-strain curves）. After training process, test data were used to check system accuracy. It is observed that feed-forward back-propagation network is the fastest, and Log-Sigmoid transfer function is giving the best results. Finally, layer recurrent nn with a single hidden layer consists of 11 neurons, and Log-Sigmoid transfer function using trainlm as training algorithm is giving good result, and average relative error is1.27 ± 1.45 %. In two hidden layers, layer recurrent nn consists of 7 neurons in each hidden layer with trainrp as the training algorithm having the transfer function of LogSigmoid which gives better results. As a result, the nn is founded successful for the prediction of stress-strain curve of near b titanium alloy.

关键词： Artificial neural network (Ann) Stressstrain curve Titanium alloys

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Borescopic particle image velocimetry in bubbling gas-solid fluidized beds

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Particuology 2019年第2期17卷 66-75页

作者： M. Banaei r. Dellaert n.g. Deen J.A.M. Kuipers M. van Sint Annaland Multiphase reactors group Department of Chemical Engineering & Chemistry Eindhoven University of Technology P.O. Box 513 5600 MB Eindhoven The Netherlands Dutch Polymer Institute (DPI) P.O. Box 902 5600 AX Eindhoven The Netherlands Multiphase and reactive Flows group. Department of Mechanical Engineering Eindhoven University of Technology P.O. Box 513 5600 MB Eindhoven The Netherlands

In this work, the borescopic particle image velocimetry (BPIV) technique was applied to a bubbling gas-solid fluidized bed, and the results were compared with published positron emission particle tracking (PEPT) measurement data. Before performing the experiments, the sensitivity of the BPIV results to the illumination power, light reflectivity of the particles, and location of the borescope was also investigated. The BPIV and PEPT results were in fair agreement;however, some discrepancies were *** difference between the two sets of results were mainly caused by the intrusiveness of BPIV, the fact that the local solids volume fraction was not accounted for in the BPIV analysis, and the intrinsic differences of these two methods. Therefore, measurement of the local solids volume fraction with the borescope is highly recommended for further development of the BPIV method, which will also enable measureme nt of the local solids mass fluxes in side dense gas-solid fluidized beds.

关键词： Borescopic particle image velocimetry gas-solid bubbling fluidized bed Solid velocity profile Experimental investigation Hydrodynamics

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Texture Evolution and Ultrafine grain Formation in Cross-Cryo-rolled Zircaloy-2

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Acta Metallurgica Sinica(English Letters) 2015年第7期28卷 837-846页

作者： Sunkulp goel r.Jayaganthan I.V.Singh D.Srivastava g.K.Dey n.Saibaba Department of Metallurgical and Materials Engineering Centre of Nanotechnology Department of Mechanical and Industrial Engineering Materials Science Division Bhabha Atomic Research Center nuclear Fuel Complex Limited

The texture and mechanical properties of cross-rolled zircaloy-2 at 77 and 300 K were *** at 77 K was performed to impart different thickness reductions of 25% and 50%,while at 300 K with 25%,50%,75% and 85% reductions to the *** analysis of deformed sample showed that near-basal orientation is not deformed completely after 50% rolling *** activation of prismatic silp,{1122} contraction twin and {1012} extension twin were evident from the deformed microstructure at 77 *** propensity for activation of basal slip〈a〉 at77 K was also *** deformation of the sample at 300 K occurs by prismatic,basal 〈a〉 and pyramidal 〈c＋a〉slips,which were predicted by pole *** annealing,the tensile strengths（735 and 710 MPa） are almost the same for 50% cryo-cross-rolled and room-temperature cross-rolled zircaloy-2 with almost 2.7% difference in their *** analysis of the deformed samples was made to estimate the stored strain energy and dislocation *** of deformed sample at 673 K for 30 min results in recrystallization,which leads to the formation of ultrafine grains.

关键词： Cross-rolling EBSD TEM Ultrafine grains Texture

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Fabrication and characterization of rugate structures composed of SiO_(2) and nb_(2)O_(5)

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光学精密工程 2005年第4期13卷 505-511页

作者： r.Leitel O.Stenzel S.Wilbrandt D.gäbler V.Janicki n.Kaiser Institut für Angewandte Physik Friedrich Schiller University JenaMax-Wien-Platz 107743 JenaGermany Optical Coatings Department Fraunhofer Institut für Angewandte Optik und FeinmechanikAlbert-Einstein-Str.7D-07745 JenaGermany Institute ruder Boskovic Bijenicka 5410000 ZagrebCroatia

gradient index layers and rugate structures were fabricated on a Leybold Syrus pro deposition system by plasma-assisted coevaporation of the low index material silica and the high index material niobium *** obtain information about the compositional profiles of the produced layers,cross sectional transmission electron microscopy was used in assistance to deposition rate data recorded by two independent crystal monitors during the film *** depth dependent concentration profiles were transformed to refractive index gradients by means of effective medium *** on the refractive index gradients the corresponding samples`transmission and reflection spectra could be calculated by utilizing matrix *** relevance of the established refractive index profiles could be verified by comparison of the calculated spectra with the measured ones.

关键词： physical vapor deposition effective medium approximation rugate structure

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Quantum dynamics of charge transfer on the one-dimensional lattice:Wave packet spreading and recurrence

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Chinese Physics B 2016年第1期25卷 817-830页

作者： V n Likhachev O I Shevaleevskii g A Vinogradov Emanuel Institute of Biochemical Physics Russian Academy of Sciences

The wave function temporal evolution on the one-dimensional （ID） lattice is considered in the tight-binding approxi- mation. The lattice consists of n equal sites and one impurity site （donor）. The donor differs from other lattice sites by the on-site electron energy E and the intersite coupling C. The moving wave packet is formed from the wave function initially localized on the donor. The exact solution for the wave packet velocity and the shape is derived at different values E and C. The velocity has the maximal possible group velocity v = 2. The wave packet width grows with time -t1/3 and its amplitude decreases ,- t-1/3. The wave packet reflects multiply from the lattice ends. Analytical expressions for the wave packet front propagation and recurrence are in good agreement with numeric simulations.

关键词： quantum dynamics tight-binding approximation charge transport

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Electro–optic response in thin smectic C* film with chevron structures

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Chinese Physics B 2016年第12期25卷 337-343页

作者： Aleksey A Kudreyko nail g Migranov Dana n Migranova Ufa State Petroleum Technological University Department of Physics Bashkir State Pedagogical University Department of General and Theoretical Physics

The effects in electrostatic models of chevron surface-stabilized ferroelectric liquid crystals are investigated through numerical modeling. To study smectic C＊ director distribution within the cell, we consider two nonlinear approaches： the chevron interface does not interplay with the electric field; the electric field interplays with the chevron interface. The obtained results of the director field distribution are compared with the earlier linearized studies. We find that whether or not the electric field interplays with the chevron interface, the electro-optic response requires a generalized approach for its description. The threshold electric field, which is necessary for switching between two stable director states in the chevron cell is evaluated. This study suggests that, in many cases of practical interest, electro-optic response to the electric field and the threshold electric field can be precisely estimated. We argue that, beside being numerically efficient, our approach provides a convenient and a novel standpoint for looking at the electro-optic response problem.

关键词： surface-stabilized ferroelectric liquid crystal chevron structure thin films bistability Euler'sequation

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gas pressure effect on plasma transport in a magnetic-filtered radio-frequency plasma source

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Plasma Science and Technology 2020年第6期22卷 103-109页

作者： n OUDInI M M ALIM r TADJInE A BEnDIB Laboratoire des Plasmas de Décharges Centre de Développement des Technologies AvancéesCitédu 20 Aout BP 17 Baba Hassen16081 AlgiersAlgeria Laboratoire d’Electronique Quantique Facultéde PhysiqueUSTHBEl Alia BP 32Bab Ezzouar 16111AlgiersAlgeria

Volume negative ion production relies on a magnetic filter(MF),where the plasma downstream of the MF is characterized by a strip-like pattern that consists of a bright and dense plasma *** this work,we study,in a radio-frequency plasma source,the effects of operating pressure on this *** investigation,conducted using a Langmuir probe,shows that the plasma uniformity might be controlled through the gas ***,the operating pressure determines on which hemi-cylinder(side of magnetic field lines)the strip *** side inversion of the high-density plasma hemi-cylinder is due to an inversion of an ambipolar electric field that changes the E?×?B drift direction.

关键词： magnetic filter radio-frequency plasma source Langmuir probe E×B drift ambipolar electric field

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Magnetically propelled Carreau fluid flow over penetrable sensor surface influenced by thermal radiation,Joule heating and heat generation

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Communications in Theoretical Physics 2022年第2期74卷 9-18页

作者： B J gireesha B nagaraja n Srikantha n g rudraswamy A Felicita Department of Studies and research in Mathematics Kuvempu UniversityShankaraghattaShivamoggaKarnatakaIndia Department of Mathematics MS Ramaiah Institute of TechnologyBangaloreIndia Department of Mathematics P.C.Jabin Science College(Autonomous)HubballiIndia

This examination emphasizes the analysis of thermal transmission of Carreau fluid flow on a permeable sensor surface equipped with radiation,Joule heating,an internal heat source,and a magnetic *** the above effects and assumptions,the equations that administer the flow are formulated.A configured system of equations is productively reduced to a system of ordinary differential *** reduced system is then dealt with using the runge–Kutta-Fehlberg fourth–fifth order tool equipped by the shooting *** numerical solutions are utilized to plot graphs and *** conclusion of the study outlines some important findings such as the power law index,the thermal radiation parameter and the heat source parameter enhance the thermal panel whereas the Weissenberg number deescalates the *** power law index and permeable velocity decrease the velocity panel *** representation of streamlines of the flow has been given to strengthen the study.A detailed description has been produced about the results obtained in the study.

关键词： sensor surface Carreau fluid squeezed flow thermal radiation heat generation

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