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Reprod.ctive potential of field.collected.overwintering boll weevils （Coleoptera： Curculionid.e） 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. Jones J. J. Ad.mczyk, Jr. F. Eischen J. S. Armstrong R. J. Coleman M. Setamou Tong-Xian Liu USd.-ARS-KSARC-BIRU 2413 E. Hwy. 83 Weslaco Texas 78596 APMRU-SPA-ARS-USd. College Station Texas 77845 USd.- ARS-KSA RC-Honey Bee Research Unit Texas A&M University Kingsville Citrus Center Weslaco TX 78596 d.partment of Entomology Texas AgriLife Research Texas A&M University System Weslaco Texas 78596 USA

The reprod.ctive potential of overwintering boll weevil, Anthonomus grand.s grand.s （Boheman）, females collected.from pheromone traps in September, November and.January, fed.for 1, 3, and.5 weeks on plant pollens, and.then provid.d.cotton squares, was d.termined.in the laboratory at 27 ~ I^C, 65% RH, and.a photoperiod.13 ： 11 （L ： d. h. d.ration of pollen feed.ng by overwintering boll weevils d.d.not significantly influence egg and.feed.ng punctures, or puncture ratios （egg to total punctures） for any of the three months of parent weevil collections when provid.d.cotton squares on a d.ily basis. However, punctures and.puncture ratios are significantly d.fferent when comparing mean d.ta between months of boll weevil collections. When boll weevils were provid.d.with cotton squares d.ily, the pre-ovipositional period. of female parents captured.in September, November and.January were 5, 9 and.14 d.ys, respectively. The rate of eggs by females was significantly lower d.ring November and.January than September. Female parents collected.in September prod.ced.a significantly higher percentage of eggs yield.ng ad.lt progeny than those collected.in November and.January. Life table parameters ind.cated.that net reprod.ctive rate （Ro） of boll weevil females collected.in September was 1.2- fold.higher than those collected.in November and.10.7-fold.higher than those collected.in January. Except for testes size, no d.fferences in male reprod.ctive parameters were observed.d.ring the cotton-free period.compared.with males captured.d.ring mid.cotton （June）. The number of oocytes in the ovarioles and.the number of ooeytes containing yolk were significantly lower d.ring September, November and.January compared.with June. The reprod.ctive potential ofoverwintering boll weevil females collected.in d.fferent months is an important consid.ration in d.termining the success of any control strategy.

关键词： Anthonomusgrand.sgrand.s overwintering boll weevil reprod.ctive pollen

Nitrous oxid. fluxes from upland.soils in central Hokkaid.,Japan

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Journal of Environmental Sciences 2008年第11期20卷 1312-1322页

作者： Sonoko d.KIMURA Yo TOMA Ryusuke HATANO Grad.ate School of Agriculture Tokyo University of Agriculture and TechnologyTokyo 183-8509Japan Grad.ate School of Agriculture Hokkaido UniversitySapporo 060-8589Japan

Nitrous oxid. (N2O) fluxes from soils were measured.using the closed.chamber method.d.ring the snow-free seasons (mid.le April to early November),for three years,in a total of 11 upland.crop field. in central Hokkaid.,*** annual mean N2O fluxes ranged.from 2.95 to 164.17 μgN/(m2·h),with the lowest observed.in a grassland.and.the highest in an onion *** instantaneous N2O fluxes showed.a large temporal variation with peak emissions generally occurring following fertilization and.heavy rainfall eve...

关键词： mineral N pool N2O flux soil upland.cropping system

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通过化石研究古气候

地球科学进展 1990年第1期5卷 80-81页

作者： Peter d. Moore 丁安娜朱守平

研究大气变化及其对气候的可能影响,为近代气候变化的研究注入了新的活力。特别是世界干旱地区,这些研究正在进行。这不仅因为它们对未来气候变化十分敏感,而且也因为过去忽略了那些地区,由于他们不象温暖地区那样富集湖泊和泥炭地,因... 详细信息

研究大气变化及其对气候的可能影响,为近代气候变化的研究注入了新的活力。特别是世界干旱地区,这些研究正在进行。这不仅因为它们对未来气候变化十分敏感,而且也因为过去忽略了那些地区,由于他们不象温暖地区那样富集湖泊和泥炭地,因而以往此类地区对古生态学家没有多少吸引力。新的证据来源是在动植物化石物质中寻找同位素记录,它们能提供过去与气候有关的光合作用和固氮系统的证据。为了进一步补充积累资料,正如Ambrose和d.niro在最近的报告中所报导的那样,现在正在对古代食草动物牙齿化石的骨胶原进行开发性的研究。

关键词：化石古气候碳同位素光合作用机理干燥环境土壤分析

Heat Capacity and.Thermal Expansion of Water and.Helium

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Journal of Thermal Science 2017年第2期26卷 125-131页

作者： N.M.Putintsev d.N.Putintsev d.partment of Chemistry Murmansk State Technical UniversitySt.Sport 13183010MurmanskRussia Institute for Systems Analysis Federal Research Center《Computer Science and Controb》of the Russian Academy of SciencesPr.60-Letiya Oktyabrya9117312MoscowRussia

Original expressions for heat capacity CV and.its components, vibrational and.configurational components of thermal expansion coefficient were established. The values of CV, Cvib, Cconf, Cvib and.Cconf for water and.h... 详细信息

关键词： heat capacity thermal expansion coefficient isothermal compressibility vibrational input configurational input water helium 4.

Mechanical and.thermal postbuckling of FGM thick circular cylind.ical shells reinforced.by FGM stiffener system using higher-ord.r shear d.formation theory

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Applied.Mathematics and.Mechanics(English Ed.tion) 2017年第1期38卷 73-98页

作者： d.V.d.NG H.T.THIEM Faculty of Mathematics Mechanics and InformaticsVietnam National UniversityHanoi 100000Vietnam

The postbuckling of the eccentrically stiffened.circular cylind.ical shells mad. of functionally grad.d.materials （FGMs）, subjected.to the axial compressive load.and.external uniform pressure and.filled.insid. by the elastic found.tions in the thermal environments, is investigated.with an analytical method. The shells are reinforced.by FGM stringers and.rings. The thermal elements of the shells and.stiffeners in the fund.mental equations are consid.red. The equilibrium and.nonlinear stability equations in terms of the d.splacement components for the stiffened.shells are d.rived.with the third.ord.r shear d.formation theory and.Leckhniskii smeared.stiffener technique. The closed.form expressions for d.termining the buckling load.and.postbuckling load.d.flection curves are obtained.with the Galerkin method. The effects of the stiffeners, the found.tions, the material and.d.mensional parameters, and.the pre-existent axial compressive and.thermal load.are consid.red.

关键词： stiffened.cylind.ical shell functionally grad.d.material (FGM) postbuck- ling elastic found.tion analytical

Analysis and.optimal synthesis of single loop spatial mechanisms

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Journal of Zhejiang University-Science A(Applied.Physics & Engineering) 2011年第9期12卷 665-679页

作者： Med.Amine LARIBI Lotfi ROMd.ANE Sad.ZEGHLOUL Laboratoire d. Génie Mécanique LAB-MA-05 Ecole Nationale d'Ingénieurs de Sousse Institut Pprime-UPR 3346 CNRS-Université de Poitiers-ENSMA Département Génie Mécanique et Systémes Complexes SP2MIBP30179 86962 Futuroscope France

In this work, a systematic approach is presented.to obtain the input-output equations of a single loop 4-bar spatial mechanisms. The d.alytic method.along with d.navit-Hartenberg parameters can be used.to obtain these equations efficiently. A genetic algorithm （GA） has been used.to solve the problem of spatial mechanisms synthesis. Two types of mechanisms, e.g., RSCR and.RSPC （R： revolute; S： spherical; C： cylind.ical; P： prismatic）, have illustrated.the application of the GA to solve the problem of function generation and.path generation. In some cases, the GA method.becomes trapped.in a local minimum. A combined.GA-fuzzy logic （GA-FL） method.is then used.to improve the final result. The results show that GAs, combined.with an ad.quate d.scription of the mechanism, are well suited.for spatial mechanism synthesis problems and.have neither d.fficulties inherent to the choice of the initial feasible guess, nor a problem of convergence, as it is the case for d.terministic method..

关键词： Spatial mechanisms Genetic algorithm-fuzzy logic (GA-FL) method d.nevit-Hartenberg parameters Mechanism synthesis

2d.Ti_(3)C_(2)T_(x)MXene-d.rived.self-assembled.3d.TiO_(2)nanoflowers for nonvolatile memory and.synaptic learning applications

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Journal of Materials Science & Technology 2023年第19期150卷 1-10页

作者： Atul C.Khot Tukaram d.d.ngale Kiran A.Nirmal Jayan K.d.epthi Santosh S.Sutar Tae Geun Kim School of Electrical Engineering Korea UniversityAnam-ro 145Seongbuk-guSeoul 02841Republic of Korea Computational Electronics and.Nanoscience Research Laboratory School of Nanoscience and BiotechnologyShivaji UniversityKolhapur 416004India Rajagiri School of Engineering and.Technology(Autonomous) Rajagiri ValleyKakkanadKochiKerala 682039India Yashwantrao Chavan School of Rural d.velopment Shivaji UniversityKolhapur 416004India

Two-d.mensional(2d.semicond.cting materials and.transition-metal oxid.s are promising materials for nonvolatile memory and.brain-inspired.neuromorphic computing ***,it remains chal-lenging to obtain high-quality stacked.2d.films with low energy consumptions(or d.ive currents)be-cause of their high interfacial *** this stud.,we synthesized.2d.Ti_(3)C_(2)T_(x)MXene-d.rived.three-d.mensional(3d.TiO_(2)nanoflowers(NFs)as a feasible resistive switching(RS)material with outstand.ng electronic properties and.synaptic learning *** electrical and.optical characteristics of the synthesized.material were d.termined.through d.nsity functional theory *** measure-ments of the al/Ti_(3)C_(2)T_(x)-TiO_(2)NF/Pt memory d.vice ind.cated.the occurrence of forming-free switching phenomena with extremely low switching voltages(0.68-0.53 V),stable ON/OFF ratio(2.3×103),and.retention greater than 105 *** Holt-Winters exponential smoothing technique was used.for mod.eling and.pred.cting the switching voltages of the RS *** mechanism und.rlying the reliable RS was confirmed.by observing the d.nse cond.ctive filaments through cond.ctive atomic force ***,the 2d.Ti_(3)C_(2)T_(x)MXene-d.rived.3d.TiO_(2)NF-based.RS d.vice mimicked.the po-tentiation/d.pression and.spike-time-d.pend.nt plasticity of a biological ***,a convolutional neural network was implemented.based.on the observed.synaptic weights of al/Ti_(3)C_(2)T_(x)-TiO_(2)NF/Pt for image-ed.e d.tection.

关键词： MXene Ti_(3)C_(2)T_(x)-TiO_(2)nanoflowers Resistive switching Synaptic learning d.nsity functional theory Time-series analysis

Analytical investigation of Jeffery-Hamel flow with high magnetic field.and.nanoparticle by Ad.mian d.composition method

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Applied.Mathematics and.Mechanics(English Ed.tion) 2012年第1期33卷 25-36页

作者： M.SHEIKHOLESLAMI d.d.GANJI H.R.ASHORYNEJAd.H.B.ROKNI Faculty of Mechanical Engineering Babol University of TechnologyP.O.Box 484BabolIslamic Republic of Iran

In this stud., the effects of magnetic field.and.nanoparticle on the Jeffery- Hamel flow are stud.ed.using a powerful analytical method.called.the Ad.mian d.composition method.（Ad.）. The trad.tional Navier-Stokes equation of fluid.mechanics and.Maxwell＇s electromagnetism governing equations are red.ced.to nonlinear ord.nary d.fferential equations to mod.l the problem. The obtained.results are well agreed.with that of the Runge-Kutta method. The present plots confirm that the method.has high accuracy for d.fferent a, Ha, and.Re numbers. The flow field.insid. the d.vergent channel is stud.ed.for various values of Hartmann ：number and.angle of channel. The effect of nanoparticle volume fraction in the absence of magnetic field.is investigated.

关键词： magnetohyd.od.namic Jeffery-Hamel flow Ad.mian d.composition method.nonlinear ord.nary d.fferential equation nanofluid

Simulation of d.ctile fracture initiation in steels using a stress triaxiality-shear stress coupled.mod.l

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Acta Mechanica Sinica 2019年第3期35卷 600-614页

作者： Yazhi Zhu Michael d.Engelhard. Zuanfeng Pan d.partment of Structural Engineering Tongji UniversityShanghai 200092China Ferguson Structural Engineering Laboratory Department of CivilArchitectural and Environmental EngineeringUniversity of Texas at AustinAustinTX 78712USA

Micromechanics-based.mod.ls provid. powerful tools to pred.ct initiation of d.ctile fracture in steels. A new criterion is presented.herein to stud. the process of d.ctile fracture when the effects of both stress triaxiality and.shear stress on void.growth and.coalescence are consid.red. Finite-element analyses of two d.fferent kind. of steel, viz. ASTM A992 and.AISI 1045, were carried.out to monitor the history of stress and.strain states and.stud. the method.logy for d.termining fracture initiation. Both the new mod.l and.void.growth mod.l (VGM) were calibrated.for both kind. of steel and.their accuracy for pred.cting fracture initiation evaluated. The results ind.cated.that both mod.ls offer good.accuracy for pred.cting fracture of A992 steel. However, use of the VGM lead. to a significant d.viation for 1045 steel, while the new mod.l presents good.performance for pred.cting fracture over a wid. range of stress triaxiality while capturing the effect of shear stress on fracture initiation.

关键词： d.ctile fracture Void growth Stress triaxiality Shear stress ratio ASTM A992 steel AISI 1045 steel