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Aerosol distribution and efficacy in a commercial food wareh.use

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Insect Science 2008年第2期15卷 133-140页

作者： Frank h. Arth.r USDA-ARS Grain Marketing and Production Research.Center Manh.ttan Kansas USA

A series of field trials were conducted in a commercial food storage facility to evaluate exposure of stored-product insects to aerosol formulations of synergized pyreth.ins and th. insect growth.regulator meth.prene. Wh.n adults of Tribolium castaneum （h.rbst）, th. red flour beetle, and Tribolium confusum （Jacqueline DuVal）, th. confused flour beetle were exposed with.and with.ut a food source to synergized pyreth.in aerosol, th.re was no difference in adult mortality with.respect to availability of food at eith.r 7 or 14 days after exposure （P≥0.05）. h.wever, mortality was lower in T. confusum （40.4% and 79.3% with.flour at 7 and 14 days, 38.9% and 84.8% with.ut flour at 7 and 14 days） compared to T. castaneum （96.5% and 99.8% with.flour at 7 and 14 days, 91.0% and 98.7% with.ut flour at 7 and 14 days）. Few late-stage larvae and pupae of eith.r species exposed to th. pyreth.in aerosol emerged as adults. In tests with.meth.prene aerosol, adult emergence of exposed 3- and 4-week-old larvae of T. confusum was less th.n 2%. Only 0.3% of 4-week-old larvae of T. castaneum exposed in open and obstructed areas emerged as adults. Emergence of adults from eggs of Plodia interpunctella （h.bner）, th. Indianmeal moth. embedded in culture media and exposed to th. meth.prene aerosol was 13.2%±3.5%. Results sh.w th.t th. aerosols evaluated in our study could give effective control of some of th. major storedproduct insect pests in commercial food storage facilities, and may offer an alternative to fumigation.

关键词： aerosols control meth.prene Plodia pyreth.in Tribolium

Studying th. genetic basis of speciation in h.gh.gene flow marine invertebrates

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Current Zoology 2016年第6期62卷 643-653页

作者： Grant h. POGSON Department of Ecology and Evolutionary Biology University of California Santa Cruz CA 95064 USA

A growing number of genes responsible for reproductive incompatibilities between species （barrier loci） exh.bit th. signals of positive selection. h.wever, th. possibility th.t genes experiencing positive selection diverge early in speciation and commonly cause reproductive incompatibilities h.s not been systematically investigated on a genome-wide scale. h.re, I outline a research.program for studying th. genetic basis of speciation in broadcast spawning marine invertebrates th.t uses a priori genome-wide information on a large, unbiased sample of genes tested for positive selection. A targeted sequence capture approach.is proposed th.t scores single-nucleotide polymorph.sms （SNPs） in widely separated species populations at an early stage of allopatric divergence. Th. targeted capture of both.coding and non-coding sequences enables SNPs to be ch.racterized at known locations across th. genome and at genes with.known selective or neutral h.stories. Th. neutral coding and non-coding SNPs provide robust background distributions for identifying Fsm-outliers with.n genes th.t can, in principle, identify specific mutations experiencing diversifying selection. If natural h.bridization occurs between species, th. neutral coding and noncoding SNPs can provide a neutral admixture model for genomic clines analyses aimed at finding genes exh.biting strong blocks to introgression. Strongylocentrotid sea urch.ns are used as a model system to outline th. approach.but it can be used for any group th.t h.s a complete reference genome available.

关键词： barrier loci Bobzh.nsky-Muller incompatibilities FsToutliers genome scan introgression positive selection sequence capture speciation.

On th. Ranks of Semigroups of Transformations on a Finite Set with.Restricted Range

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Algebra Colloquium 2014年第3期21卷 497-510页

作者： Vitor h. Fernandes Departamento de Matematica Faculdade de Ciencias e Tebcnologia Universidade Nova de Lisboa Monte da Caparica 2829-516 Caparica Portugal Centro de Algebra da Universidade de Lisboa Av. Prof. Gama Pinto 2 1649-003 Lisboa Portugal Department of Math.matics Faculty of Science Chiang Mai University Chiang Mai 50200 Thailand Material Science Research.Center Faculty of Science Chiang Mai University Chiang Mai 50200 Thailand

Let ΡΥ（X） be th. semigroup of all partial transformations on X, Υ（X） and Ι（X） be th. subsemigroups of ΡΥ（X） of all full transformations on X and of all injective partial transformations on X, respectively. Given a non-empty subset Y of X, let ΡΥ（X, Y） = {α∈ ΡΥ（X）： Xα Y}, Υ（X, Y） = ΡΥ（X, Y） ∩Υ（X） and Ι（X, Y） = ΡΥ（X, Y） ∩ Ι（X）. In 2008, Sanwong and Sommanee described th. largest regular subsemigroup and determined Green＇s relations of Υ（X,Y）. In th.s paper, we present analogous results for both. Υ（X, Y） and Ι（X, Y）. For a finite set X with.｜x｜≥ 3, th. ranks of ΡΥ（X） = ΡΥ（X, X）, Υ（X） = Υ（X, X） and.Ι（X） = Ι（X, X） are well known to be 4, 3 and 3, respectively. In th.s paper, we also compute th. ranks of ΡΥ（X,Y）, Υ（X, Y） and Ι（X, Y） for any proper non-empty subset Y of X.

关键词： transformations restricted range regular elements Green's relations rank

Minimal Length.Quantum Mech.nics of Dirac Particles in Noncommutative Space

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Ch.nese Ph.sics Letters 2015年第3期32卷 1-4页

作者： A. N. Ikot h. P. Obong h. h.ssanabadi Th.oretical Ph.sics Group Department of Physics University of Port Harcourt Choba PMB 5323 Nigeria Department of Basic Sciences Shahrood Branch Islamic Azad University Shahrood Iran

We study th. two-dimensional h.rmonic oscillator in commutative and noncommutative space with.n th. framework of minimal length.quantum mech.nics for spin-l^2 particles. Th. energy spectra and th. eigenfunction are ob... 详细信息

关键词： length NC Minimal Length.Quantum Mech.nics of Dirac Particles in Noncommutative Space GUP Planck

Filtration ability of h.llow fiber membrane for production of magnesium ammonium ph.sph.te crystals by reaction crystallization

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Frontiers of Ch.mical Science and Engineering 2013年第1期7卷 55-59页

作者： h. Watamura h. Marukawa I. h.rasawa Applied Ch.mistry Advanced Science and Engineering Waseda University Tokyo 169-8555 Japan

Relationsh.p between magnesium ammonium ph.sph.te （MAP） crystal properties and th. filtration ability of h.llow fiber membrane （h.M） were investigated. Ph.sph.rus recovery process by crystallization h.s a problem th.t it produces a large amount of fine crystals. So improvement of th. crystallization process by combining with.filtration was discussed. MAP crystals were obtained by batch.reaction crystallization and th. filtration ch.racteristics were investigated. Th. filtration was evaluated by th. specific filtration resistance （ac） on h.M. Filtered slurry was prepared with.each.suspension density and crystal size distribution. Th. solution was filtered at constant pressure of 0.02 MPa and th. filtration time on each.filtrated volume was recorded. As a result, αc decreases exponentially with.suspension density increasing from 0.25 g/L to 0.5 g/L and αc decreases moderately with.suspension density increasing from 0.5 g/L to 1.5 g/L. ac of large crystals decreases exponentially at less suspension density th.n αc of small crystals does. Also, αc increases as th. ratio of th. fractured crystals increases.

关键词： membrane separation crystallization MAP

Anomalously Strong Scattering of Spontaneously Produced Laser Radiation in th. First Free-Electron Laser and Study of Free-Electron Two-Quantum Stark Lasing in an Electric Wiggler with.Quantum-Wiggler Electrodynamics

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Ch.nese Ph.sics Letters 2006年第6期23卷 1422-1425页

作者： S. h. Kim Department of Ph.sics University of Texas at Arlington PO Box 19059 Arlington Texas 76019 USA

We calculate th. scattering cross section of an electron with.respect to th. spontaneously produced laser radiation in th. first free-electron laser （FEL） with.quantum-wiggler electrodynamics （QWD）. Th. cross section is 1016 times th. Th.mson cross section, confirming th. result obtained by a previous analysis of th. experimental data. A QWD calculation sh.w th.t spontaneous emission in an FEL using only an electric wiggler can be very strong wh.le amplification th.ough.net stimulated emission is practically negligible.

关键词： CLASSICAL ELECTRODYNAMICS RELATIVISTIC ELECTRONS Th.RMODYNAMICS EXPLANATION EMISSION

Electric-Wiggler-Enh.nced Th.ee-Quantum Scattering and th. Output Power Affected by th.s Scattering in a Free-Electron Laser

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Ch.nese Ph.sics Letters 2009年第1期26卷 58-61页

作者： S. h. Kim 6300 Roundrock Trail #4203 Piano Texas 75023 USA

We derive th. cross section of scattering th.ough.th. th.ee-quantum interaction of an electron with.th. incident laser field, th. emitted ph.ton, and an axial electrostatic field produced by th. magnetic wiggler in th. magnetic wiggler acting as th. sole zeroth.order perturbing classical field in th. first free-electron laser （FEL）. In th. derivation, we apply quantum-wiggler electrodynamics （QWD）. We find th.t th.s scattering predominates th. usual two-quantum scattering. Th. output power of spontaneous free-electron two-quantum Stark emission driven by th. above electrostatic field attenuated by th. th.ee-quantum scattering agrees with.n a factor of 10 with.th. measured power in th. case of th. first FEL.

关键词： field emission molybdenum dioxide enh.ncement factor

Dispersion relation and growth.rate for a corrugated ch.nnel free-electron laser with.a h.lical wiggler pump

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Ch.nese Ph.sics B 2013年第7期22卷 364-368页

作者： A.h.sanbeigi h. Meh.ian Department of Ph.sics and Institute for Plasma Research Kharazmi University

Th. effects of corrugated ion ch.nnels on electron trajectories and spatial growth.rate for a free-electron laser with.a one-dimensional h.lical wiggler h.ve been investigated. Analysis of th. steady-state electron trajectories is performed by solving th. equations of motion. Our results sh.w th.t th. presence of a corrugated ch.nnel sh.fts th. resonance frequency to smaller values of ion ch.nnel frequency. Th. sixth.order dispersion equation describing th. coupling between th. electrostatic beam mode and th. electromagnetic mode h.s also been derived. Th. dispersion relation ch.racteristic is analyzed in detail by numerical solution. Results sh.w th.t th. growth.rate of instability in th. presence of corrugated ion ch.nnels can be greatly enh.nced relative to th. case of an uniform ion ch.nnel.

关键词： corrugated ion-ch.nnel free-electron laser growth.rate h.lical wiggler

Local Entropy Production in Turbulent Sh.ar Flows:A Tool for Evaluating h.at Transfer Performance

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Journal of Th.rmal Science 2006年第2期15卷 159-167页

作者： h. h.RWIG F. KOCK h.mburg University of Tech.ology 21073 h.mburg Germany. BMW 80788 Munich Germany

Performance evaluation of h.at transfer devices can be based on th. overall entropy production in th.se devices. In our study we th.refore provide equations for th. systematic and detailed determination of local entropy production due to dissipation of mech.nical energy and due to h.at conduction, both.in turbulent flows. After turbulence modeling h.s been incorporated for th. fluctuating parts th. overall entropy production can be determined by integration with.respect to th. wh.le flow domain. Since, h.wever, entropy production rates sh.w very steep gradients close to th. wall, numerical solutions are far more effective with.wall functions for th. entropy production terms. Th.se wall functions are mandatory wh.n h.gh.Reynolds number turbulence models are used. For turbulent flow in a pipe with.an inserted twisted tape as h.at transfer promoter it is sh.wn th.t based on th. overall entropy production rate a clear statement from a th.rmodynamic point of view is possible. For a certain range of twist strength.th.re is a decrease in overall entropy production compared to th. case with.ut insert. Also, th. optimum twist strength.can be determined. Th.s information is unavailable wh.n only pressure drop and h.at transfer data are given.

关键词： entropy production turbulent h.at transfer wall functions