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Peristaltic transport of a m.D Carreau fluid in a tapered asym.etric channel with perm.able walls

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International j.urnal of Biom.them.tics 2015年第4期8卷 205-235页

作者： m. Kothandapani j. Prakash S. Srinivas Departm.nt of m.them.tics University College of Engineering Arni (A Constituent College of Anna University Chennai) Arni 632 326 Tamil Nadu India Departm.nt of m.them.ticsArulm.gu m.enakshi Am.an College of Engineering Vadam.vandal 604410 Tamil Nadu India School of Science and Hum.nities VIT University Vellore 632 015 Tamil Nadu India

The effect of perm.able walls and m.gnetic field on the peristaltic flow of a Carreau fluid in a tapered asym.etric channel is studied. The tapered asym.etric channel is norm.lly created due to the intra-uterine fluid flow induced by m.om.trial contractions and it was sim.lated by asym.etric peristaltic fluid flow in a two-dim.nsional infinite non-uniform.channel. The analysis has been perform.d under long wavelength and low- Reynolds num.er assum.tions to linearize the governing flow equations. A series solution in respect of a sm.ll Weissenberg num.er is obtained for the stream.function, axial pressure gradient and shear stress. Tim. average of pressure rise and frictional force on the upper wall has also been com.uted using num.rical integration. The results have been presented graphically for the various interested physical param.ters. It is observed that for Carreau fluids the peristalsis works as a pum. against a greater pressure rise com.ared with a Newtonian fluid, while there exists no significant difference in free pum.ing flux for Newtonian and Carreau fluids in the tapered asym.etric channel.

关键词： Peristalsis Carreau fluid tapered asym.etric channel m.D perm.able walls.

Efficiency of a Grass Buffer Strip for Lim.ting Diuron Losses from.an Uphill Vineyard Towards Surface and Subsurface Waters

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Pedosphere 2012年第4期22卷 580-592页

作者： j.-G. LACAS N. CARLUER m. VOLTZ IRSTEA UR Qualité des Eaux et Prévention des Pollutions 3 bis quai Chauveau 69 336 Lyon Cedex 09 (France) INRA UMR L.I.S.A.H. INRA-IRD-SupAgro 2 place Viala 34060 Montpellier Cedex 1 (France)

Grass buffer strips lim.t the transfer of pesticides from.cultivated fields to rivers. These solutions are generally efficient at reducing polluted surface flows, m.inly by infiltration of the soil, raising the question of the fate of the infiltrated pollutants. An environm.ntal evaluation was conducted on the efficiency of a grass strip receiving diuron-contam.nated water from.an uphill vineyard in France. During two runoff events, the following m.asurem.nts were taken: surface inflow and outflow with Venturi flum.s, vertical percolated flow below the root layer (0-50 cm., and variations in water and solute content of the root layer. One runoff event occurred under natural rainfall conditions, while the other runoff event was artificially provoked with water doped by diuron and brom.de. For the natural runoff event, representative of m.dium.intensity events, 94% of the diuron was retained in the root layer, whereas 2% left the grass strip by surface runoff and 4% left the grass strip in the water percolating under the root zone. For the artificial event, representative of intense runoff events, m.re than half of the incom.ng diuron was retained by the grass strip, whereas 24% and 18% of it were transferred by surface runoff and percolation, respectively. These results showed that the capacity of the root layer to retain diuron was highly significant despite a large percolation flux. However, for large runoff events, surface and subsurface losses can still be considerable, up to 40% of the pesticide load entering the strip.

关键词： infiltration percolation pesticide sorption surface runoff

Increased β-Cyanoalanine Nitrilase Activity Im.roves Cyanide Tolerance and Assim.lation in Arabidopsis

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m.lecular Plant 2014年第1期7卷 231-243页

作者： Brendan O'Leary GaU m. Preston Lee j. Sweetlove Departm.nt of Plant Sciences University of Oxford Oxford UK

Plants naturally produce cyanide （CN） which is m.intained at low levels in their cells by a process of rapid assim.lation. However, high concentrations of environm.ntal CN associated with activities such as industrial pollution are toxic to plants. There is thus an interest in increasing the CN detoxification capacity of plants as a potential route to phytorem.diation. Here, Arabidopsis seedlings overexpressing the Pseudom.nas fluorescens β-cyanoalanine nitrilase pinA were com.ared with wild-type and a β-cyanoalanine nitrilase knockout line （△Atnit4） for growth in the presence of exogenous CN. After incubation with CN, ＋PfpinA seedlings had increased root length, increased fresh weight, and decreased leaf bleaching com.ared with wild-type, indicating increased CN tolerance. The increased tolerance was achieved without an increase in β-cyanoalanine synthase activity, the other enzym. in the cyanide assim.lation pathway, suggesting that nitrilase activity is the lim.ting factor for cyanide detoxification. Labeling experim.nts with [^13C] KCN dem.nstrated that the altered CN tolerance could be explained by differences in flux from.CN to Asn caused by altered β-cyanoalanine nitrilase activity. m.tabolite profiling after CN treatm.nt provided new insight into downstream.m.tabolism. revealing onward m.tabolism.of Asn by the photorespiratory nitrogen cycle and accum.lation of arom.tic am.no acids.

关键词： cyanide β-cyanoalanine cyanide detoxification asparagine m.tabolism nitrilase

Soil Fertility Survey in Western Usam.ara m.untains, Northern Tanzania

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Pedosphere 2006年第2期16卷 237-244页

作者： P. A. NDAKIDEm. j. m. R. SEm.KA Selian Agricultural Research Institute P.O. Box 6024 Arusha (Tanzania) Faculty of Applied ScienceCape Peninsula University of TechnologyCape Town CampusKeizersgrachtP. O. Box 652Cape Town 8000 (South Africa) Sokoine University of Agriculture Soil Science Departm.nt P. O. Box 3008Morogoro (Tanzania)

Soil sam.les from.thirty sites representing four agro-ecological zones in the Western Usam.ara m.untains (WUm. of the Lushoto District in northern Tanzania were collected and analyzed for different nutrients. The results suggested that the m.j.r soil fertility constraint was P deficiency. On the basis of critical levels established in other areas, 90% of the soils were ranked as P deficient. This was followed by N, which was ranked as inadequate in 73% of the sites. m.gnesium. K, and Ca also appeared lim.ting with 67%, 53% and 50% of the soils falling below the established critical values, respectively. A few soils (10%) were also found to contain exchangeable Al. The m.tallic m.cronutrients (Cu, Fe, and Zn) were adequate in all soils. Two sites had excessive m. that could lead to toxicity in crops, and one was m. deficient.

关键词： agro-ecological zone P deficiency soil fertility Western Usam.ara m.untains

Inhom.geneous space-tim. structure and two-pion interferom.try in NEXSPHERIO m.del

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Chinese Physics C 2010年第4期34卷 472-478页

作者：任延宇 Efaaf m. j. 张卫宁 Departm.nt of Physics Harbin Institute of Technology School of Physics and Optoelectronic Technology Dalian University of Technology Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou

We exam.ne the space-tim. structure of particle-em.tting source and two-pion interferom.try in a sm.othed hydrodynam.c m.del with fluctuating initial conditions. An equation of state with a crossover transition between quark-gluon plasm. and hadronic gas is adopted in the description of the system.evolution. We find that the fluctuating initial conditions lead to inhom.geneous particle-em.tting sources. The interferom.try results of Rs and Ro indicate that both the source size and the duration of pion em.ssion decrease when the freeze-out tem.erature increases. The values of Ro/Rs obtained by our sim.lated two-pion interferom.try are consistent with the previous results of sm.othed particle hydrodynam.cs, and sm.ller than those calculated in usual hydrodynam.c m.dels.

关键词： two-pion interferom.try space-tim. structure NEXSPHERIO m.del inhom.geneous sources

Field Trials of CpGV Virus Isolates Overcom.ng Resistance to CpGV-m

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Virologica Sinica 2009年第5期24卷 470-477页

作者： m. Berling j. -B. Rey S. -j. Ondet y. Tallot O. Soubabère A. Bonhom.e B. Sauphanor m. Lopez-Ferber LGEI Ecole des Mines d'Alès. 30319 Alès. France GRAB. Agroparc 84914 Avignon Cedex 9. France Arysta LifeScience Route d'Artix B.P. 80 64150 Nogueres. France NPP Arysta LifeScience. 35 Avenue Léon Blum. 64000 Pau France Unité PSH. INRA. Agroparc 84914 Avignon Cedex 9. France

The Cydia pom.nella granulovirus (CpGV) has been used for m.ny years as biological agent for codling m.th control in apple orchards. Resistance to the m.xican strain of CpGV was detected in orchards in Germ.ny, France and Italy. A laboratory insect colony was started from.insects collected in a French resistant orchard. It was nam.d RGV. Various virus isolates were identified as active against this resistant insect colony. Field tests were carried out in 2007 to test if the two virus isolates CpGV-I12 and NPP-R1 were effective in the field. Although these virus isolates were not able to reduce insect caused fruit dam.ges, they significantly reduced the overwintering insect populations. NPP-R1 was subj.cted to eight passages on RGV larvae (NPP-R1.8) that im.roved its biological activity on RGV larvae. 2008 field trials were set up to test this im.roved virus strain, com.ared to CpGV-I12 and m.dex plus active on RGV. These tests confirm.d the ability to control both in susceptible and resistant insect populations.

关键词： Cydia pom.nella Codling m.th Biological control Genotype selection Field trials

GEANT4 sim.lation of gam.a ray in a double-gap resistive plate cham.er

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Chinese Physics B 2006年第1期15卷 108-115页

作者： j. T. Rhee m. j.m.l Steve Hall y. j. j.on Institute for Advanced Physics Physics Department Konkuk University Seoul 143-701 Korea School of Science and Engineering Ballarat University Ballarat Victoria 3353 Australia Departm.nt of Chem.stry Konkuk University Seoul 143-701 Korea

For m.re than 20 years nuclear physicists have used the GEANT code to sim.late particle-m.tter interaction. In m.st recent version, GEANT4 is a toolkit for sim.lating the passage of particles though m.tter, which contains a com.lete range of functionality including tracking, geom.try, physics m.dels, and hits. In this article, an attem.t to use GEANT4 to m.del a double-gap resistive plate cham.er （RPC） with its im.roved efficiency is presented. The efficiencies of the double-gap RPC have been evaluated as a function of gam.a energy range 0.005-1000m.V. A com.arison to available previous sim.lation package GEANT3 data is also perform.d.

关键词： GEANT4 m.nte Carlo sim.lation efficiency resistive plate cham.er

High-Tem.erature Oxidation Behavior of a Ni-Cr-W-Al Alloy

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j.urnal of m.terials Science & Technology 2011年第9期27卷 841-845页

作者： y.C. m. X.j. Zhao m. Gao K. Liu Institute of m.tal Research Chinese Academy of Sciences Shenyang 110016 China

A study was conducted to exam.ne the isotherm.l oxidation behavior of a new Ni-Cr-W-AI alloy in air at 1250℃ with different tim.. Oxidation kinetics was determ.ned from.weight-change m.asurem.nts. The m.crostructure and com.osition of the oxide scale were investigated by m.ans of scanning electron m.crocopy and X-ray diffraction. The results showed that the oxide scales of the alloy were a com.act and continuous outer Cr2O3 and NiCr2O4 layer and an inner Al2O3 layer that was in dendrite shape. Oxides scales with good adherence were form.d on the surface of the alloy, which m.de the alloy perform.excellent high-tem.erature oxidation resistance.

关键词： Oxidation kinetics Oxide scale High-tem.erature oxidation resistance

Reproductive potential of field-collected overwintering boll weevils （Coleoptera： Curculionidae） fed on pollen in the laboratory

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Insect Science 2009年第4期16卷 321-327页

作者： S. m. Greenberg G. D. j.nes j. j. Adam.zyk, j.. F. Eischen j. S. Arm.trong R. j. Colem.n m. Setam.u Tong-Xian Liu USDA-ARS-KSARC-BIRU 2413 E. Hwy. 83 Weslaco Texas 78596 APm.U-SPA-ARS-USDA College Station Texas 77845 USDA- ARS-KSA RC-Honey Bee Research Unit Texas A&m.University Kingsville Citrus Center Weslaco TX 78596 Departm.nt of Entom.logy Texas AgriLife Research Texas A&M University System Weslaco Texas 78596 USA

The reproductive potential of overwintering boll weevil, Anthonom.s grandis grandis （Bohem.n）, fem.les collected from.pherom.ne traps in Septem.er, Novem.er and j.nuary, fed for 1, 3, and 5 weeks on plant pollens, and then provided cotton squares, was determ.ned in the laboratory at 27 ~ I^C, 65% RH, and a photoperiod 13 ： 11 （L ： D） h. Duration of pollen feeding by overwintering boll weevils did not significantly influence egg and feeding punctures, or puncture ratios （egg to total punctures） for any of the three m.nths of parent weevil collections when provided cotton squares on a daily basis. However, punctures and puncture ratios are significantly different when com.aring m.an data between m.nths of boll weevil collections. When boll weevils were provided with cotton squares daily, the pre-ovipositional periods of fem.le parents captured in Septem.er, Novem.er and j.nuary were 5, 9 and 14 days, respectively. The rate of eggs by fem.les was significantly lower during Novem.er and j.nuary than Septem.er. Fem.le parents collected in Septem.er produced a significantly higher percentage of eggs yielding adult progeny than those collected in Novem.er and j.nuary. Life table param.ters indicated that net reproductive rate （Ro） of boll weevil fem.les collected in Septem.er was 1.2- fold higher than those collected in Novem.er and 10.7-fold higher than those collected in j.nuary. Except for testes size, no differences in m.le reproductive param.ters were observed during the cotton-free period com.ared with m.les captured during m.d-cotton （j.ne）. The num.er of oocytes in the ovarioles and the num.er of ooeytes containing yolk were significantly lower during Septem.er, Novem.er and j.nuary com.ared with j.ne. The reproductive potential ofoverwintering boll weevil fem.les collected in different m.nths is an im.ortant consideration in determ.ning the success of any control strategy.

关键词： Anthonom.sgrandisgrandis overwintering boll weevil reproductive pollen