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Nanoparticle mig.ation ef.ects on f.lly developed f.rced convection of.TiO2-water nanof.uid in a parallel plate microchannel

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Particuolog. 2016年第1期14卷 96-107页

作者： f. Hedayati g. Domairry Young.Researchers and Elite Club Neyshabur Branch Islamic Azad University Neyshabur Iran Mechanical Eng.neering.Department Babol University of Technology Babol lran

This study considers the f.rced convection of.laminar TiO2-water nanof.uid f.ow in a parallel plate microchannel. The small leng.h scale associated with microchannels dictates the use of.slip condition at the f.id-solid interf.ce. The modif.ed Buong.orno model was employed f.r the nanof.uid to f.lly account f.r the ef.ects of.non-unif.rm viscosity and thermal conductivity. The partial dif.erential equa- tions associated with conservation laws were reduced to two-point ordinary boundary value dif.erential equations bef.re being.numerically solved. Considering.Brownian motion and thermophoresis, the ef.ects of.nanoparticle transport on concentration, velocity, and temperature prof.les were analyzed f.r three dif.erent values of.wall heat f.ux. To assess the ef.iciency of.adding.nanoparticles, the ratios of.the pres- sure drop and the heat transf.r coef.icient of.the nanof.uid to that of.the base f.uid were studied in detail. f.om analyzing.dif.erent heat f.ux ratios, one-sided heating.was f.und to be most ef.icient at enhancing.the heat transf.r rate in the microchannel. Additionally, in the presence of.the slip velocity, the increase in the value of.the heat transf.r coef.icient f.r the nanof.uid was smaller than that f.r the base f.uid.

关键词： Nanof.uid Microchannel Nanoparticles mig.ation Slip velocity Brownian motion Thermophoresis

The integ.ated use of.chemical insecticides and the entomopathog.nic nematode, Steinemema carpocapsae （Nematoda： Steinernematidae）, f.r the control of.sweetpotato whitef.y, Bemisia tabaci （Hemiptera： Aleyrodidae）

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Insect Science 2008年第5期15卷 447-453页

作者： Andrew g. S. Cuthbertson j.mes j. Mathers Phil Northing.Anthony j. Prickett Keith f. A. Waiters Central Science Laboratory Sand Hutton York YO41 1LZ UK

The integ.ation of.chemical insecticides and inf.ctive j.veniles of.the entomopathog.nic nematode Steinernema carpocapsae （Wesier）（Nematoda： Steinernematidae）, to control second instars of.the sweetpotato whitef.y, Bemisia tabaci g.nnadius （Hemiptera： Aleyrodidae） was investig.ted. Using.a sand bioassay, the ef.ects of.direct exposure of.S. carpocapsae f.r 24 h to f.eld rate dilutions of.f.ur insecticides （spiromesif.n, thiacloprid, imidacloprid and pymetrozine） on inf.ctivity to g.lleria mellonella larvae were tested. Althoug. all chemicals tested, except spiromesif.n, produced acceptable nematode inf.ctivity rates, they were all sig.if.cantly less than the water control. The ef.ect of.insecticide treatment （dry residues of.spiromesif.n, thiacloprid and pymetrozine and soil drench of.imidacloprid） on the ef.icacy of.the nematode ag.inst B. tabaci was also investig.ted. Nematodes in combination with thiacloprid and spiromesif.n g.ve hig.er B. tabaci mortality （86.5% and 94.3% respectively） compared to using.nematodes alone （75.2%） on tomato plants. There was no sig.if.cant dif.erence in B. tabaci mortality when using.the chemicals imidacloprid, pymetrozine and spiromesif.n in conj.nction with nematodes compared to using.the chemicals alone. However, using.thiacloprid in combination with the nematodes produced sig.if.cantly hig.er B. tabaci mortality than using.the chemical alone. The integ.ation of.S. carpocapsae and these chemical ag.nts into current integ.ated pest manag.ment prog.ammes f.r the control of.B. tabaci is discussed.

关键词： entomopathog.nic nematode inf.ctivity insecticide residue pest manag.ment

f.rther compatibility tests of.the entomopathog.nic f.ng.s Lecanicillium muscarium with conventional insecticide products f.r control of.sweetpotato whitef.y, Bemisia tabaci on poinsettia plants

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Insect Science 2008年第4期15卷 355-360页

作者： Andrew g. S. Cuthbertson Lisa f. Blackburn Phil Northing.Weiqi Luo Raymond j. C. Cannon Keith f. A. Waiters Central Science Laboratory Sand Hutton York Y041 1LZ UK

The ef.ect on spore g.rmination of.the entomopathog.nic f.ng.s Lecanicillium muscarium f.llowing.direct exposure f.r 24 h to the insecticides Maj.stik, Spray Oil, Ag.i- 50E, Savona and Oberon f.r the control of.both eg. and second instar stag.s of.the sweetpotato whitef.y, Bemisia tabaci, was determined. Exposure to both Ag.i-50E and Oberon was f.llowed by acceptable spore g.rmination. Inf.ctivity rates of.. muscarium on poinsettia f.liag. in the presence of.dry residues of.the insecticides were also investig.ted. No sig.if.cant detrimental ef.ects on the levels of.control of.B. tabaci were recorded compared with f.ng.s applied to residue-f.ee f.liag.. Sequential application of.the chemicals Savona, Spray Oil and Maj.stik with the f.ng.s all produced mortalities of.second instar B. tabaci above 90%. Incorporation of.these chemicals with L. muscarium into integ.ated control prog.ams f.r B. tabaci is discussed.

关键词： entomopathog.nic f.ng.s integ.ated pest manag.ment insecticidecompatibility Lecanicillium muscarium

Topsoil as Af.ected by Dung.Deposition Under Resting.Places of.Red Howler Monkey (Alouatta seniculus)

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Pedosphere 2008年第6期18卷 691-698页

作者： S. POUVELLE f. f.ER j. f. PONg. Musum National d'Histoire Naturelle CNRS UMR 7179 4 avenue du Petit-Chateau

The short-term inf.uence of.dung.deposition and the f.rther redistribution of.dung.by dung.beetles were studied under a resting.place of.the red howler monkey （Alouatta seniculus） living.in tropical ralnf.rests of.South America. Monkey dung.was experimentally clumped on the f.eld in a place used by troops of.howler monkeys f.r resting.in the Nourag.es Reserve Station, f.ench g.iana. Dung.treated plots were sampled serially over three weeks and compared with controls located in their immediate vicinity. The composition of.the soil matrix （top 10 cm） was studied in successive microlayers using.an optical method. Under the inf.uence of.dung.beetle activity, the topsoil became more homog.neous by losing.its litter, its content in earthworm f.eces increased in the course of.time, and surf.ce mineral deposits were penetrated by roots. The results were interpreted in the lig.t of.present knowledg. on the ef.ects of.soil animal activity on plant g.owth and survival of.seedling..

关键词： dung.beetle activity earthworm f.eces roots tropical ralnf.rests

Issues in the Mining.of.Heart f.ilure Datasets

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International j.urnal of.Automation and computing 2014年第2期11卷 162-179页

作者： Nong.uch Poolsawad Lisa Moore Chandrasekhar Kambhampati j.hn g.f.cleland Intellig.nt Systems Research g.oup(IS Department of Computer Science) University of Hull Hull York Medical School Department of CardiologyUniversity of Hull

This paper investig.tes the characteristics of.a clinical dataset using.a combination of.f.ature selection and classif.cation methods to handle missing.values and understand the underlying.statistical characteristics of.a typical clinical dataset. Typically, when a larg. clinical dataset is presented, it consists of.challeng.s such as missing.values, hig. dimensionality, and unbalanced classes. These pose an inherent problem when implementing.f.ature selection and classif.cation alg.rithms. With most clinical datasets, an initial exploration of.the dataset is carried out, and those attributes with more than a certain percentag. of.missing.values are eliminated f.om the dataset. Later, with the help of.missing.value imputation, f.ature selection and classif.cation alg.rithms, prog.ostic and diag.ostic models are developed. This paper has two main conclusions: 1) Despite the nature of.clinical datasets, and their larg. size, methods f.r missing.value imputation do not af.ect the f.nal perf.rmance. What is crucial is that the dataset is an accurate representation of.the clinical problem and those methods of.imputing.missing.values are not critical f.r developing.classif.ers and prog.ostic/diag.ostic models. 2) Supervised learning.has proven to be more suitable f.r mining.clinical data than unsupervised methods. It is also shown that non-parametric classif.ers such as decision trees g.ve better results when compared to parametric classif.ers such as radial basis f.nction networks(RBf.s).

关键词： Heart f.ilure clinical dataset classif.cation clustering missing.values f.ature selection.

Interf.cial ef.ects in electromag.etic coupling.within piezoelectric phononic crystals

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Acta Mechanica Sinica 2009年第1期25卷 95-99页

作者： f. j. Sabina A.B.Movchan Instituto de Investig.ciones en Matematicas Aplicadas yen Sistemas Universidad Nacional Autónoma de México Department of.Mathematical Sciences University of Liverpool

In this paper, we discuss waves in piezoelectric periodic composite, with the emphasis on the connection between the electromechanical coupling.and the ef.ects of.dispersion of.Bloch-f.oquet waves. A particular attention is g.ven to structures containing.interf.ces between dissimilar media and localization of.the electrical f.elds near such interf.ces.

关键词： Piezoelectric periodic composites Interf.ces Dispersion of.Bloch-f.oquet waves

Oxidation and Coating. f.r Power g.neration： New Super Ultra Critical Steam Turbines

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中国腐蚀与防护学报 2009年第4期29卷 318-319页

作者： f. j. PEREZ g.upo de Investig.cion de Ing.nieria de Superf.cies y Materiales Nanoestructurados U. C. M. N°910627 f.cultad de Ciencias Quimicas Universidad Complutense de Madrid. 28040 Madrid Spain

The steels with chromium contents between 9%and 12%wt are used f.r power plants with advanced steam oxidation *** present g.od creep properties as 9%Cr steels and g.od oxidation resistance,at the temperatures rang. between 500℃～600℃.In the last years numerous investig.tion in development of.coating. has been realized with the aim the protected them ag.inst the oxidation in order to allow operation of.steam turbines at 650℃.In this study,Al-Hf.protective coating. were deposited by CVD-f.R on f.rritic steel HCM-12A f.llowed by a dif.usion heat treatment,have shown to be protective at 650℃under steam f.r at least 3000 hours of.laboratory steam exposure under atmospheric *** and composition of.coating. were characterized by dif.erent techniques, such as scanning.electron microscopy(SEM),electron probe microanalysis,and X-ray dif.raction(XRD). On the other hand,volatile species by mass spectrometry(MS) and thermog.avimetric measurements (Tg. during.the initial stag.s oxidation of.the P92 f.rritic steel without and of.Al and Al/Si coating.by chemical vapour deposition in f.uidized bed reactors(CVD-f.R) at 650℃in Ar+20%H_2O f.r 150 h were *** order to g. f.rward to coating. desig. the Thermocalc code is used as base f.r the MSdata. Tg.MS experiments were conducted in a closed steam loop in order to obtain inf.rmation about the oxyhydroxides f.rmation as reaction between coating. and *** those results the role of.the dif.erent coating.element could be established and optimized f.r the coating.*** oxidation mechanism based on the Tg.MS results is *** morpholog./composition and structure of.the oxidized samples were also studied using.SEM/EDS and XRD techniques.

关键词：氧化金属腐蚀防护

Analysis of.Heat Transf.r Phenomenon in Mag.etohydrodynamic Casson f.uid f.ow Throug. Cattaneo–Christov Heat Dif.usion Theory

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Communications in Theoretical Physics 2017年第7期67卷 91-95页

作者： g. K. Ramesh j. g.reesha, S. A. Shehzad, f. M. Abbasi Department of.Mathematics School of Engineering Presidency University Bengaluru-560089 Karnataka India Department of.Studies and Research in Mathematics Kuvempu University Shankaraghatta-577451 Shimoga Karnataka India Department of.Mathematics COMSATS Institute of Information Technology Sahiwal-57000 Pakistan Department of.Mathematics COMSATS Institute of Information Technology Islamabad-44000 Pakistan

Heat transport phenomenon of.two-dimensional mag.etohydrodynamie Casson f.uid f.ow by employing.Cattaneo-Christov heat dif.usion theory is described in this work. The term of.heat absorption/g.neration is incorporated in the mathematical modeling.of.present f.ow problem. The g.verning.mathematical expressions are solved f.r velocity and temperature prof.les using.RKf.45 method along.with shooting.technique. The importance of.arising.nonlinear quantities namely velocity, temperature, skin-f.iction and temperature g.adient are elaborated via plots. It is explored that the Casson parameter retarded the liquid velocity while it enhances the f.uid temperature. f.rther, we noted that temperature and thickness of.temperature boundary layer are weaker in case of.Cattaneo-Christov heat dif.usion model when matched with the prof.les obtained f.r f.urier＇s theory of.heat f.ux.

关键词： Hydromag.etic f.ow Casson f.uid heat transf.r Cattaneo-Christov heat dif.usion model numer-ical solution

Streng.hening.an in-service reinf.rcement concrete bridg. with prestressed Cf.P bars

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j.urnal of.Zhej.ang.University-Science A(Applied Physics & Eng.neering. 2009年第5期10卷 635-644页

作者： Hai-long.WANg.Wei-liang.j.N David j. cleland Ai-hui ZHANg Department of.Civil Eng.neering Zhejiang University Hangzhou 310027 China School of.Planning Architecture and Civil Engineering Queen's University Belfast Belfast BT9 5AG UK

Carbon f.ber reinf.rced polymer (Cf.P) bars were prestressed f.r the structural streng.hening.of.8 T-shaped rein-f.rced concrete (RC) beams of.a 21-year-old bridg. in China. The ultimate bearing.capacity of.the existing.bridg. af.er retrof.t was discussed on the basis of.concrete structures theory. The f.exural streng.hs of.RC beams streng.hened with Cf.P bars were controlled by the f.ilure of.concrete in compression and a prestressing.method was applied in the retrof.t. The f.eld construction processes of.streng.hening.with Cf.P bars-including.g.outing.cracks, cutting.g.oove, g.outing.epoxy and embedding.Cf.P bars, surf.ce treating. banding.with the U-type Cf.P sheets, releasing.external prestressed steel tendons-were introduced in detail. In order to evaluate the ef.ectiveness of.this streng.hening.method, f.eld tests using.vehicles as live load were applied bef.re and af.er the retrof.t. The test results of.def.ection and concrete strain of.the T-shaped beams with and without streng.hening.show that the capacity of.the repaired bridg., including.the bending.streng.h and stif.ness, is enhanced. The measurements of.crack width also indicate that this streng.hening.method can enhance the durability of.bridg.s. Theref.re, the proposed streng.hening.technolog. is f.asible and ef.ective.

关键词： Carbon f.ber reinf.rced polymer (Cf.P) bar Reinf.rced concrete (RC) bridg. Streng.hening Construction pro-cedure f.eld test T-shaped beam