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Journal of Forestry Research 2014年第3期25卷 717-721页

作者： Namera c.Karun P.Vaast c.g.Kushalappa Department of Bioscience Mangalore University cIRAD UMR Eco&Sols Montpellier France IcRAF NairobiKenya college of Forestry (University of Agriculture Sciences) Ponnmpet Coorg 571216 India

Forty-five species of wild edible fruits were identified and traditional local knowledge of their usage was recorded in 40 villages of Kodagu district in central Western ghats, India one of the eight top hotspots of biodiversity in the world. We combined biodiversity inven-tory of trees with village interviews to record traditional ecological knowledge. Wild edible fruits were an opportunistic source of food for rural people. Wild edible fruits were rich in minerals, vitamins, carbohy-drates, proteins, fats and fiber. In recent years there has been a decline in numbers of wild fruit trees due to changes in land use from uncultivated private wooded area to cardamom and coffee cultivation. The availability of wild edible fruits that were once very common on private cultivated areas has declined and their distributions are now restricted more to jungles and wildlife sanctuaries. We propose methods for conservation and describe the need for sustainable utilization to provide supplemen-tary sources of nutritional and pharmaceutically useful edible wild fruits.

关键词： wild edible fruits nutraceutical biodiversity Kodagu,western ghats.

Fullwave Doppler reflectometry simulations for density turbulence spectra in ASDEX Upgrade using gENE and IPF-FD3D

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Plasma Science and Technology 2020年第6期22卷 41-48页

作者： c LEcHTE g D cONWAY TgÖRLER T HAPPEL the ASDEX Upgrade Team Institute of Interfacial Process Engineering and Plasma Technology IgVP Universität StuttgartD-70569 StuttgartGermany Max-Planck-Institute for Plasma Physics D-85748 GarchingGermany 不详

Doppler reflectometry is an important microwave diagnostic for turbulent fusion plasmas.A microwave beam is scattered off density fluctuations,with wavenumbers according to incident frequency and relative *** way,a density fluctuation spectrum is ***,the correspondence between fluctuation power and scattered microwave power is strongly *** these processes numerically therefore requires fullwave simulations(IPF-FD3 D),with density fluctuations supplied by a separate plasma turbulence code(gENE).Earlier such attempts suffered from the low number of data points in the‘interesting’part of the spectrum,where a power law had to be fitted to 4 or 5 *** has been overcome with recent simulations,which now show a much better agreement with experimental data.

关键词： plasma diagnostics Doppler reflectometry simulation microwaves

Damage detection on framed structures: modal curvature evaluation using Stockwell Transform under seismic excitation

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Earthquake Engineering and Engineering Vibration 2015年第2期14卷 265-274页

作者： R.Ditommaso F.c.Ponzo g.Auletta Department of Structures Geotechnics Engineering Geology University of Basilicata School of Engineering University of Basilicata

The key parameters for damage detection and localization are eigenfrequencies, related equivalent viscous damping factors and mode shapes. The classical approach is based on the evaluation of these structural parameters before and after a seismic event, but by using a modern approach based on time-frequency transformations it is possible to quantify these parameters throughout the ground shaking phase. In particular with the use of the S-Transform, it is possible to follow the temporal evolution of the structural dynamics parameters before, during and after an earthquake. In this paper, a methodology for damage localization on framed structures subjected to strong motion earthquakes is proposed based on monitoring the modal curvature variation in the natural frequency of a structure. Two examples of application are described to illustrate the technique: computer simulation of the nonlinear response of a model, and several laboratory(shaking table) tests performed at the University of Basilicata(Italy). Damage detected using the proposed approach and damage revealed via visual inspections in the tests are compared.

关键词： damage detection S-transform band-variable fi lter

cFD Simulation of a Hydrogen/Argon Plasma Jet Reactor for coal Pyrolysis

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chemical Research in chinese Universities 2004年第4期20卷 446-451页

作者： cHEN H. g. XIE K. c. Taiyuan University of Technology Taiyuan University of Technology Taiyuan 030024 P. R. China City University London EC1V 0HB UKand Taiyuan 030024 P. R. China

A computational Fluid Dynamics(cFD) model was formulated for Dc arc hydrogen/argon plasma jet reactors used in the process of the thermal H_2/Ar plasma pyrolysis of coal to acetylene. In this model, fluid flow, convective heat transfer and conjugate heat conductivity are considered simultaneously. The error caused by estimating the inner-wall temperature of a reactor is avoided. The thermodynamic and transport properties of the hydrogen/argon mixture plasma system, which are usually expressed by a set of discrete data, are fitted into expressions that can be easily implemented in the program. The effects of the turbulence are modeled by two standard k-εequations. The temperature field and velocity field in the plasma jet reactor were calculated by employing SIMPLEST algorithm. The knowledge and insight obtained are useful for the design improvement and scale-up of plasma reactors.

关键词： Plasma Reactor computational fluid dynamics coal pyrolysis

Determination of slug permeability factor for pressure drop prediction of slug flow pneumatic conveying

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Particuology 2008年第5期6卷 307-315页

作者： Kenneth c.Williams Mark g.Jones Tobias Krull centre for Bulk Solids and Particulate Technology The University of NewcastleCallaghanNSW 2308Australia

current models for pressure drop prediction of slug flow pneumatic conveying in a horizontal pipeline system assume some type of steady state conditions for prediction, which limits their capability for increased predictive accuracy relative to experimental data. This is partly because of the nature of slug flow pneumatic conveying system, which, as a dynamic system, never becomes stable. By utilising conservation of mass （airflow）, a dynamic pressure analysis model is proposed on the basis of the derivative of the upstream pressure behaviour. The rate of air permeation through slug, one of the important factors in the conservation model, is expressed as a function of a slug permeability factor. Other factors such as slug velocity, slug length and the fraction of stationary layer were also considered. Several test materials were conveyed in single-slug tests to verify the proposed pressure drop model, showing good agreement between the model and experimental results.

关键词： Slug flow pneumatic conveying Pressure drop Air mass conversation Slug permeability factor

Low symmetry aspects in spectroscopic and magnetic susceptibility studies of Tb^(3+)(4f^8) in TbAlO_3

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Journal of Rare Earths 2009年第4期27卷 627-632页

作者： c.Rudowicz P.gnutek M.g.Brik Modeling in Spectroscopy group Institute of Physics West Pomeranian University of Technology Institute of Physics University of Tartu

The three sets of crystal field parameters （cFPs） obtained from spectroscopic and magnetic susceptibility studies of Tb3＋（4f^8） ions in TbAlO3 by gruber et al. （J. Lumin. 128 （2008） 1271） were reanalyzed. These sets, fitted from experimental energy levels, are physically equivalent and correspond to specific choices of the axis system. Proper interpretation of experimental data for Tb3＋ ions at monoclinic c8 symmetry sites in TbAlO3 crystal requires clarification of several intricate low syrmnetry aspects, namely, （a） three equivalent forms of monoclinic cF Hamiltouian, （b） relative orientation of the crystallographic axis system w.r.t, the symmetry-adapted axis system, （c） monoclinic standardization of cFPs, （d） distinction between the actual and apparent low symmetry effects exhibited by cFPs, and （e） nominal nature of all fitted cFP sets. For this purpose, modeling of cFPs for Tb3＋ in TbAlO3 was carried out using at the first stage only the coulomb, i.e. point charge, eonlribntions in the exchange charge model. The point charge model calculated cFPs disagree with the experimental cFPs, especially the rank k=6 cFPs. To explain this discrepancy and to verify the correcmess of the theoretical cFP calculations additionally the superposition model was employed. The methods of analysis and modeling of cFP sets for monoclinic symmetry cases proposed here proved useful for the studied case as well as might be used for other ion-host systems exhibiting monoclinic or triclinic local site symmetry. Partial results for Tb3＋ ions in TbAlO3 were presented here, whereas detailed results were given in a follow-up paper.

关键词： Tb3+ ions TbAlO3 spectroscopy crystal-field magnetic susceptibility low symmetry aspects rare earths

Effects of second diffusing component and cross diffusion on primary and secondary thermoconvective instabilities in couple stress liquids

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Applied Mathematics and Mechanics(English Edition) 2017年第11期38卷 1579-1600页

作者： R.RAVI c.KANcHANA P.g.SIDDHESHWAR Department of Humanities and Sciences National Institute of Technology GoaGoa 403401India Department of Mathematics Jnana Bharathi CampusBangalore UniversityBangalore 560056India

Linear and weakly nonlinear analyses are made for the Rayleigh-Benard convection in two-component couple-stress liquids with the Soret effect. conditions for pitchfork, Hopf, Takens-Bogdanov, and codimension-two bifurcations are presented. The Lorenz model is used to study the inverted bifurcation. Positive values of the Soret coefficient favor a pitchfork bifurcation, whereas negative values favor a Hopf bifurcation. Takens-Bogdanov and codimension-two bifurcations are not as much influenced by the Soret coefficient as pitchfork and Hopf bifurcations. The influence of the Soret coefficient on the inverted bifurcation is similar to the influence on the pitchfork bifurcation. The in- fluence of other parameters on the aforementioned bifurcations is also similar as reported earlier in the literature. Using the Newell-Whitehead-Segel equation, the condition for occurrence of Eckhaus and zigzag secondary instabilities is obtained. The domain of ap- pearance of Eckhaus and zigzag instabilities expands due to the presence of the Soret coefficient for positive values. The Soret coefficient with negative values enhances heat transport, while positive values diminish it in comparison with heat transport for the case without the Soret effect. The dual nature of other parameters in influencing heat and mass transport is shown by considering positive and negative values of the Soret coefficient.

关键词： codimension-two Eckhaus inverted Lorenz Newell-Whitehead-Segel,Nusselt number Rayleigh-B^nard secondary instability Sherwood number Takens-Bogdanov zigzag

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Acta Mechanica Sinica 2020年第6期36卷 1294-1301,I0003页

作者： c.g.chai A.g.Pi Q.M.Li F.L.Huang Institute of chemical Materials China Academy of Engineering PhysicsMianyang621900China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China School of Mechanical Aerospace and Civil EngineeringUniversity of ManchesterManchesterM139PLUK

Similarity can reflect common laws in the mechanism of rigid-body *** this paper,the similarities in rigid-body penetration depth are demonstrated by three non-dimensional but physically meaningful quantities,i.e.,ρkinetic,I∗ln and N′*** three quantities represent the non-dimensional areal density of projectile kinetic energy,the effect of nose geometry,and the friction at the interactive cross section between projectile and target *** is shown that experimental data of rigid projectile penetration,from shallow to deep penetration,can be uniquely unified by these three similarity quantities and their ***,for ogival nose projectiles,their penetration capacities are dominated byρkinetic,which is consisted by non-dimensional effective length Leff and non-dimensional quantity Dpn=ρpv20AY which has the same form as Johnson’s damage *** the sacrifice of minor theoretical accuracy,the non-dimensional penetration depth P/d can be understood as directly controlled by Dpn,enhanced by projectile effective length Leff under a multiplication relation,and optimized by projectile nose geometry in the formation of I∗ln.

关键词： concrete target Deep penetration Similarity-Johnson's damage number

Variation in sexual dimorphism and assortative mating do not predict genetic divergence in the sexually dimorphic goodeid fish girardinichthys multiradiatus

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current Zoology 2012年第3期58卷 440-452页

作者： c. MAcIAS gARcIA g SMITH c. gONZALEZ ZUARTH J. A. gRAVES M. g. RITcHIE Departamento de Ecologia Evolutiva Instituto de Ecologia UNAM A. E 70-275 C. E 04510 M6xico DE M6xico School of Biology University of St Andrews St Andrews Fife KY16 9TH Scotland UK

Sexual dimorphism is often used as a proxy for the intensity of sexual selection in comparative studies of sexual selection and diversification. The Mexican goodeinae are a group of livebearing freshwater fishes with large variation between species in sexual dimorphism in body shape. Previously we found an association between variation in morphological sexual dimorphism between species and the amount of gene flow within populations in the goodeinae. Here we have examined if mor- phological differentiation within a single dimorphic species is related to assortative mating or gene flow between populations. In the Amarillo fish girardinichthys multiradiatus studies have shown that exaggerated male fins are targets of female preferences. We find that populations of the species differ in the level of sexual dimorphism displayed due to faster evolution of differences in male than female morphology. However, this does not predict variation in assortative mating tests in the laboratory; in fact dif- ferences in male morphology are negatively correlated with assortative mating. Microsatellite markers reveal significant genetic differences between populations. However, gene flow is not predicted by either morphological differences or assortative mating. Rather, it demonstrates a pattern of isolation by distance with greater differentiation between watersheds. We discuss the caveats of predicting behavioural and genetic divergence from so-called proxies of sexual selection [current Zoology 58 （3）： 440-452, 2012].

关键词： Sexual dimorphism Assortative mating genetic distance Speciation Viviparous fish

New insights into the hardening and pitting corrosion mechanisms of thermally aged duplex stainless steel at 475℃:A comparative study between 2205 and 2101 steels

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Journal of Materials Science & Technology 2022年第3期98卷 123-135页

作者： R.Silva g.S.Vacchi c.L.Kugelmeier I.g.R.Santos A.A.Mendes Filho D.c.c.Magalhães c.R.M.Afonso V.L.Sordi c.A.D.Rovere Munir Rachid corrosion Laboratory Department of Materials EngineeringFederal University of São CarlosRodovia Washington Luis Km 23513565-905 São CarlosSPBrazil Engineering Modeling and Applied Social Sciences Center(CECS)Federal University of ABCAvenida dos Estados 500109210580 Santo AndréSPBrazil Federal University of São carlos Graduate Program in Materials Science and EngineeringBrazil

In this study,the relationship between spinodal decomposition and the formation of Ni-rich clusters and g-phase in the ferrite on hardening and pitting corrosion of two thermally aged duplex stainless steels(DSSs)at 475℃was *** indicate that,for 2205 DSS,pitting corrosion behavior is influenced by the presence and size of g-phase precipitates for longer aging times,but this contribution is masked by the advanced stage of spinodal decomposition in the ferritic *** the other hand,for 2101 DSS,the formation of cr-richer nitrides impairs pitting corrosion resistance more than spinodal decomposition.

关键词： Duplex stainless steel Spinodal decomposition g-phase precipitation Pitting corrosion Hardening