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寄主植物对小菜蛾实验种群生物学参数的影响(英文)

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华南农业大学学报 2002年第4期23卷 18-22页

作者： sYED t.s. ABRO G.H. 陆永跃梁广文塞因德农业大学昆虫学系华南农业大学昆虫学系广东广州510642

实验观察了小菜蛾取食不同种白菜和油菜的主要生物学参数 ,包括幼虫、蛹的历期、蛹质量、化蛹率、羽化率和雌虫产卵量 .结果表明 :(1)取食苔菜 (Brassicacamelina)幼虫历期最短 ,取食花椰菜 (B .***)幼虫历期最长 ;(2 )取食不同蔬菜化... 详细信息

实验观察了小菜蛾取食不同种白菜和油菜的主要生物学参数 ,包括幼虫、蛹的历期、蛹质量、化蛹率、羽化率和雌虫产卵量 .结果表明 :(1)取食苔菜 (Brassicacamelina)幼虫历期最短 ,取食花椰菜 (B .***)幼虫历期最长 ;(2 )取食不同蔬菜化蛹率变化明显 ,其中以白芥 (Brassicaalba)最高达 90 .7% ,羽化率变化很大 ,以欧州油菜 (Brassicanapus)最高达 84 % ;(3)蛹质量也因寄主不同而异 ,取食蔬菜B .napus最低为 5 .6 8mg ,取食香花芥菜 (E .sativus)最高为 7.5 4mg .(4)取食香花芥菜雌虫产卵量最高为 16 5 .5 0粒 ;(5 )蛹质量和寄主含氮量 ,产卵量和寄主含氮量 ,产卵量和蛹质量分别相关性显著 ,并建立了回归方程分别为 :Y =4 .0 92 7+0 .6 5 0 5N ,Y =- 118.5 74 0 +5 7.5 6 2 5N和Y =- 379.4 2 0 +71.881X .

关键词：寄主植物小菜蛾实验种群生物学参数

COORDINAtING A tWO-ECHELON sUPPLY CHAIN tHROUGH DIFFERENt CONtRACts UNDER PRICE AND PROMOtIONAL EFFORt-DEPENDENt DEMAND

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Journal of systems science and systems Engineering 2013年第3期22卷 295-318页

作者： B.C.GIRI s.BARDHAN t.MAItI Department of Mathematics Jadavpur UniversityIndia

Retail price and promotional effort are two important parameters on which demand of a commodity largely depends. this paper develops and analyzes a two-echelon supply chain where market demand depends on both retail price and sales effort. the centralized model is studied as the benchmark case, and the wholesale price-only contract is studied as the base case in which each entity tries to maximize its individual profit. Different contract mechanisms are implemented to outperform the base case in terms of both total chain＇s as well as individual profits. Comparisons among the coordinating contracts are provided so that any entity may choose the better one from available contracts after the contract parameters are negotiated. the model is extensively examined through a numerical example.

关键词： Price and effort-dependent demand wholesale price-only contract wholesale price discount revenue sharing profit.s.aring two-part tariff

Exact.s.lutions in generalized Oldroyd-B fluid

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Applied Mathematics and Mechanics(English Edition) 2012年第4期33卷 411-426页

作者： t. HAYAt.s. ZAIB s. AsGHAR A. A. HENDI Department of Mathematics Quaid-i-Azam University Department of Mathematics Comsats Institute of Information Technology Department of Physics Faculty of Science King Saud University

this investigation deals with the influence of slip condition on the magne- tohydrodynamic （MHD） and rotating flow of a generalized Oldroyd-B （G. Oldroyd-B） fluid occupying a porous space. FractionM calculus approach is used in the mathematical modeling. three illustrative examples induced by plate oscillations and periodic pressure gradient are considered, and the exact.s.lutions in each case are derived. Comparison is provided between the results of slip and no-slip conditions. the influence of slip is highlighted on the velocity profile by displaying graphs.

关键词： slip condition exact.s.lution fractional calculus

Optimizing pulsed current gas tungsten arc welding parameters of AA6061 aluminium alloy using Hooke and Jeeves algorithm

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中国有色金属学会会刊：英文版 2008年第5期18卷 1028-1036页

作者： s.BABU t.s.NtHIL KUMAR V.BALAsUBRAMANIAN Centre for Materials Joining Research (CEMAJOR) Department of Manufacturing EngineeringAnnamalai UniversityAnnamalai Nagar-608 002Tamil NaduIndia Department of Automobile technology Bharathidasan Institute of TechnologyAnna UniversityTiruchirappalli-620 016Tamil NaduIndia

though the preferred welding process to weld aluminium alloy is frequently constant current gas tungsten arc welding (CCGtAW),it resulted in grain coarsening at the fusion zone and heat affected zone(HAZ).Hence,pulsed current gas tungsten arc welding(PCGtAW) was performed,to yield finer fusion zone grains,which leads to higher strength of AA6061 (Al-Mg-si) aluminium alloy *** order to determine the most influential control factors which will yield minimum fusion zone grain size and maximum tensile strength of the joints,the traditional Hooke and Jeeves pattern search method was *** experiments were carried out based on central composite design with 31 runs and an algorithm was developed to optimize the fusion zone grain size and the tensile strength of pulsed current gas tungsten arc welded AA6061 aluminium alloy *** results indicate that the peak current (Ip) and base current (IB) are the most.s.gnificant parameters,to decide the fusion zone grain size and the tensile strength of the AA6061 aluminum alloy joints.

关键词：脉冲电流钨电极惰性气体保护焊铝合金颗粒尺寸

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岩石(节选)

初中生 2024年第21期 22-23页

作者： t.s.艾略特不详

我们在生存中迷失的生活在哪里?我们在知识中遗失的智慧在哪里?我们在信息中丢失的知识在哪里?

关键词：遗失信息智慧

A theoretical t.s. of the Geostrophic Momentum Approximation

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Advances in Atmospheric sciences 1992年第2期9卷 251-255页

作者： t.s.spassova Institute of Meteorology and Hydrology Bulgarian Academy of Sciences Sofia previously developed model of a 2-dimensional air flow with constant horizontal shear is used to estimeate the accuracy of the geostrophic momentum approximation by comparison of exact solutions when exist with approximate ones.

A previously developed model of a 2-dimensional air flow with constant horizontal shear is used to estimeate the accuracy of the geostrophic momentum approximation by comparison of exact.s.lutions when exist with appr... 详细信息

关键词： Approximation exact approximate momentum thank preserved formulated ordina symmetry assumed

Constraining the temperature-density Relation of the Inter-galactic Medium from Analytically Modeling LyαForest Absorbers

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Research in Astronomy and Astrophysics 2023年第4期23卷 72-84页

作者： Li Yang Zheng Zheng t.-s.Kim shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China school of Astronomy and space sciences University of Chinese Academy of SciencesBeijing 100049China Department of Physics and Astronomy University of Utah115 S 1400 ESalt Lake CityUT 84112USA Department of Astronomy University of Wisconsin475 North Charter StreetMadisonWI 53706USA

the absorption by neutral hydrogen in the intergalactic medium(IGM)produces the Lya forest in the spectra of *** Lya forest absorbers have a broad distribution of neutral hydrogen column density N_(HⅠ) and Doppler b *** narrowest Lya absorption lines(of lowest b)with neutral hydrogen column density above~10^(13)cm^(-2) are dominated by thermal broadening,which can be used to constrain the thermal state of the *** we constrain the temperature-density relation t=t0(ρ/■)γ^(-1) of the IGM at 1.6sing N_(HⅠ) and b parameters measured from 24 high-resolution and high-signal-to-noise quasar spectra and by employing an analytic model to model the N_(HⅠ) -dependent low-b cutoff in the b *** each N_(HⅠ) bin,the b cutoff is estimated using two methods,one non-parametric method from computing the cumulative b distribution and a parametric method from fitting the full b *** find that the IGM temperature t0 at the mean gas densityρshows a peak of~1.5×10^(4) K at z~*** redshift higher than this,the indexγapproximately remains constant,and it.s.arts to increase toward lower *** evolution in both parameters is in good agreement with constraints from completely different approaches,which signals that HeⅡreionization complet.s.around z~3.

关键词： (galaxies:)intergalactic medium-(galaxies:)quasars absorption lines-radiation mechanisms thermal

t.s.s ON stRUCtURALLY DEFICIENt RC sLABs stRENGtHENED WItH FIBRE REINFORCED POLYMER (FRP) COMPOsItEs

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工业建筑 2004年第Z1期34卷 -页

作者： s.t. smith Centre for Built Infrastructure Research Faculty of Engineering University of technology Sydney PO Box 123 Broadway NSW 2007 Australia

［1］Arduini, M., Nanni, A. and Romagnolo, M. (2004) "Performance of one-way reinforced concrete slabs with externally bonded fiber-reinforced polymer strengthening", ACI structural Journal, Vol.101, No. 2, pp. 193-201.［2］As 1012 Methods of t.s.ing Concrete, standards Australia, sydney, Australia.［3］As1391 (1991)Methods for tensile t.s.ing of Metals, standards Australia, sydney, Australia.［4］As3600 (2001) Concrete structures, standards Australia, sydney, Australia.［5］As/NZs4671 (2001) steel Reinforcing Materials, standards Australia, sydney, Australia.［6］Lam, L. and teng, J.G. (2001) “strength of RC cantilever slabs bonded with GFRP strips”,Journal of Composit.s.for Construction, AsCE, Vol. 5, No. 4, pp. 221-227.［7］seim, W., Horman, M. Karbhari, V. and seible, F. (2001) “External FRP poststrengthening of scaled concrete slabs”, Journal of Composit.s.for Construction, AsCE, Vol. 5, No. 2, pp. 67-75.［8］smith, s.t. and Gilbert, R.I. (2003) “t.s.s on RC slabs reinforced with 500 MPa welded wire fabric”, Proceedings (CD-ROM), Concrete in the 3rd Millennium, CIA 2003, 21st Biennial Conference, Concrete Institute of Australia (CIA), Brisbane, Australia, 17-19 July.［9］teng, J.G., Lam, L, Chan, W. and Wang, J. (2000) “Retrofitting of deficient RC cantilever slabs using GFRP strips”, Journal of Composit.s.for Construction, AsCE, Vol. 4, No. 2, pp. 75-84.［10］teng, J.G., Chen, J.F., smith, s.t. and Lam, L. (2002) FRP-strengthened RC structures, John Wiley & sons, Chichester, West.s.ssex, U.K., 245 pp.［11］teng, J.G., smith, s.t., Yao, J. and Chen, J.F. (2003) “Intermediate crack induced debonding in RC beams and slabs”, Construction and Building Materials, Vol. 17, No. 6-7, pp.

关键词： steel reinforcement reinforced concrete reinforced polymer

Mixed convection flow of jeffrey nanofluid with thermal radiation and double stratification

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Journal of Hydrodynamics 2016年第5期28卷 840-849页

作者： F.M.ABBAsI s.A.sHEHZAD t.HAYAt M.s.ALHUtHALI Department of Mathematics COMSATS Institute of Information Technology Islamabad Department of Mathematics Comsats Institute of Information Technology Department of Mathematics Quaid-i-Azam University Nonlinear Analysis and Applied Mathematics (NAAM) Research Group Department of MathematicsFaculty of ScienceKing Abdulaziz University

this article addresses the two-dimensional laminar boundary layer flow of magnetohydrodynamic （MHD） Jeffrey nano- fluid with mixed convection. Effects of thermal radiation, thermophoresis, Brownian motion and double stratifications are taken into account. Rosseland＇s approximation is utilized for the thermal radiation phenomenon. Convergent.s.ries solutions of velocity, tempe- rature and nanoparticle concentration are developed. Graphs of dimensionless temperature and nanoparticle concentration are prese- nted to investigate the influences of different emerging parameters. the values of skin-friction coefficient, local Nusselt and sherwood numbers are computed and discussed for both Jeffrey and viscous fluids cases. We have observed that the temperature profile retarded for the larger values of Deborah number while an enhancement is noticed with the increasing values of ratio of relaxation to retardation times. Increasing values of thermal and nanoparticle concentration stratifications lead to a reduction in the temperature and nanoparticle concentration. the values of local Nusselt and sherwood numbers are larger for the viscous fluid case when compared with Jeffrey fluid.

关键词： MHD flow Jeffrey nanofluid double stratification thermal radiation mixed convection