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Survival of boll weevil （coleoptera： curculionidae） adults after feeding on pollens from various sources

Insect Science 2007年第6期14卷 503-510页

作者： SHOIL M. GREENBERG GRETcHEN d. jones FRANK EIScHEN RANdY j. cOLEMAN jOHN j. AdAMcZYK, jR. TONG-XIAN LIU MAMOUdOU SETAMOU USdA-ARS KSARC-BIRU Weslaco USdA-ARS APMRU College Station USdA-ARS KSARC-Honey Bee Research Unit department of Entomology Texas AgriLife Research Texas A&M University System Texas A&M University Kingsville citrus center Weslaco Texas USA

The survival of overwintering boll weevil, Anthonomus grandis grandis （Boheman）, adults on non-cotton hosts in the Lower Rio Grande Valley （LRGV） of Texas was examined from 2001 to 2006. The success of the Boll Weevil Eradication Program, which was reintroduced into the LRGV in 2005, depends on controlling overwintering boll weevil populations. Laboratory studies were conducted using boll weevil adults that were captured in pheromone traps from September through March. The number of adults captured per trap declined significantly in the field from fall to the beginning of spring （3.5-7.0-fold）. The proportion of trapped males and females did not differ significantly. The mean weight of boll weevil adults captured in September was 13.3 mg, while those of captured adults from November to February were significantly lower and ranged from 6.7 to 7.8 mg. Our results show that boll weevil adults can feed on different plant pollens. The highest longevity occurred when adults were fed almond pollen or mixed pollens （72.6 days and 69.2 days, respectively） and the lowest when they fed on citrus pollen or a non-food source （9.7 days or 7.4 days, respectively）. The highest adult survival occurred on almond and mixed pollens [88.0%-97. 6% after 1st feeding period （10 days）, 78.0%-90.8% after 3rd feeding period （10 days）, 55. 0%-83.6% after 5th feeding period （10 days）, and 15.2%-32.4% after lOth feeding period （10 days）]. The lowest adult survival occurred on citrus pollen [52.0%-56.0% after 1st feeding period （10 days）, 13.3% after 3rd and 5th feeding periods （10 days）, and 0 after 6th feeding period （10 days）]. Pollen feeding is not a behavior restricted to adult boll weevils of a specific sex or physiological state. Understanding how boll weevil adults survive in the absence of cotton is important to ensure ultimate success of eradicating this pest in the subtropics.

关键词： boll weevil Anthonomus grandis grandis curculionidae subtropics pollen

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A Novel Melt Processing for Mg Matrix composites Reinforced by Multiwalled carbon Nanotubes

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journal of Materials Science & Technology 2016年第12期32卷 1303-1308页

作者： H.L.Shi X.j.Wang c.L.Zhang c.d.Li c.ding K.Wu X.S.Hu School of Materials Science and Engineering Harbin Institute of Technology

carbon nanotubes（cNTs） reinforced Mg matrix composites were fabricated by a novel melt *** novel processing consisted of two courses：cNTs pre-dispersion and ultrasonic melt *** ball-milling was employed to pre-disperse cNTs on Zinc（Zn） *** cNT entanglements were well dispersed to single cNT or tiny clusters on Zn *** ultrasonic melt processing further dispersed cNTs in the Mg melt,especially tiny cNT ***,a uniform dispersion of cNTs was achieved in the as-cast *** extrusion further improved the distribution of *** increased both the strength and elongation of the matrix ***,the elongation of the matrix alloy was enhanced by 40%.Grain refinement and the pulling-out of cNTs resulted in the evident improvement of ductility for the composites.

关键词： Pre-dispersion carbon nanotubes Magnesium matrix composites Ultrasonic

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A high specific Young's modulus steel reinforced by spheroidal kappa-carbide

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journal of Materials Science & Technology 2021年第28期87卷 54-59页

作者： P.chen j.Fu X.Xu c.Lin j.c.Pang X.W.Li R.d.K.Misra G.d.Wang H.L.Yi department of Materials Physics and chemistry School of Materials Science and Engineeringand Key Laboratory for Anisotropy and Texture of MaterialsNortheastern UniversityShenyang 110819China The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China Angang Steel company Limited Technology centre Anshan 114009China Laboratory for Excellence in Advanced Steel Research Department of MetallurgicalMaterials and Biomedical EngineeringUniversity of Texas at El Paso500 W.University AvenueEl PasoTX 79968USA

*** High strength steels continue to be developed for automotive applications to increase safety and reduce lightweight by downgauging[1,2].In addition,reducing density is another solution for the lightweight of automotive components[3,4].Aluminum addition could effectively reduce the density of steels,since it has a low atomic mass and invokes a lattice expansion[5].

关键词： carbide steel strength

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The Stochastic Regression Analysis as a Tool in Ecotoxicological QSAR Studies

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Biomedical and Environmental Sciences 1989年第4期2卷 385-393页

作者： j.dEVILLERS d.ZAKARYA M.cHASTRETTE j.c.dORE cTIS Laboratoire

correspondence factor analysis(cFA)was used in conjunction with linear regression analysis to examine the structure-activity relationships of 50 benzene derivatives tested on Pimephales *** nine molecular descriptors(numbers of c,H,O,N,Br,cl,NO_2,OH,and NH_2 included in the molecules),cFA made it possible to define five new independent variables which were introduced in a stepwise regression analysis procedure to describe the acute toxicity(96-h Lc_(50))of the aromatic *** model log 1/c=-0.727F_1+1.248F_3+4.052(r=0.918; s=0.270)is more relevant to describe the ecotoxicological behavior of the studied compounds on the fathead minnow than that obtained with principal components(log 1/c=0.151 Pc_1 -0.271 Pc_2+4.124;r=0.737;s=0.460).The heuristic potency of this particular statistical analysis,which is called stochastic regression analysis,is discussed in detail.1989 Academic Press,Inc.

关键词： QSAR The Stochastic Regression Analysis as a Tool in Ecotoxicological QSAR Studies

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Experimental Study and Numerical Simulation of the casting-Forging complex Near Net Forming of Alternator claw-pole

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上海交通大学学报 2004年第z2期38卷 79-82页

作者： j.L.Song d.j.Hu Q.c.Wang H.Q.chen H.G.Guo School of Mechanical and Power Engineering Shanghai Jiaotong University Shanghai200030 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China School of Mechanical and Power Engineering Shanghai Jiaotong University Shanghai200030 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China

As a newly developed precision technology, casting-forging complex near net forming process is utilized to produce complex components with a short lead time, low cost and high precision, thus to accelerate the response speed of the market and enhance the competitive power of products. In this paper, the casting-forging complex near net forming process of alternator claw pole was developed and investigated with a combination of experimental and numerical simulation method. Qualified near net workpiece was manufactured, mechanical parameter and relative field information during the forming process was also obtained. While the alternator claw-pole is processed with this technology, the forming force is small, the process is short and the quality of forgings is perfect. Therefore, the complex casting-forging near net forming process of claw-pole is an energy and material saving technology, which will have a vast developing and application prospect in the future.

关键词： alternator claw-pole casting-forging near net forming numerical simulation

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Influence of carrier Gas on Analysis of MgO Powders by Laser Ablation Inductively coupled Plasma Mass Spectrometry

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journal of Materials Science & Technology 2009年第3期25卷 333-335页

作者： j.S. Lee Y.S. Lee c.j. Park H.S. Lee d.S. Lee department of chemistry Yonsei University Material Analysis Team Korea Testing Laboratory Korea Research Institute of Standards and Science School of Material Science and Engineering Pusan National Univirsity

Laser ablation inductively coupled plasma mass spectrometry （LA-IcP-MS） has been widely adopted for the direct multi-elemental analysis with high sensitivity. Especially analysis of fine ceramics by LA-IcP-MS without time-consuming sample decomposition process has been one of the most expecting application field. Small additive elements in MgO powders were analyzed by LA-IcP-MS. For precise and accurate analysis influence of carrier gas （Ar or He） was presented by the signal intensities of IcP-MS, relative standard deviation of signal intensities and ablated particle size distribution. Ablated particles were collected and analyzed by scanning electron microscopy （SEM） to investigate the particle size distribution, and the ablated sample surface was examined by camscope. In He gas atmosphere, the signal was more stable than in Ar gas atmosphere. The signal intensity was higher in Ar than in He. Examination of ablated particles and sample surface reveals that more particles were generated in Ar atmosphere and the distribution of particle size was larger.

关键词： Laser ablation MgO powders carrier gas IcP-MS

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catalytic performance of zinc-supported copper and nickel catalysts in the glycerol hydrogenolysis

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journal of Energy chemistry 2020年第3期29卷 185-194页

作者： R.j.chimentao B.c.Miranda d.Ruiz F.Gispert-Guirado F.Medina j.Llorca j.B.O.Santos Physical chemistry department Faculty of Chemical SciencesUniversity of ConcepcionCasilla 160-CConcepcionChile chemical Engineering School Universidad de Costa Ric1San Jose 2060Costa Rica Scientific Resources Service Universitat Rovira i VirgiliTarragona 43007Spain department of chemical Engineering Universitat Rovira i VirgiliTarragona 43007Spain department of chemical Engineering Barcelona Research Center in Multiscale Science and EngineeringInstitute of Energy TechnologiesUniversitat Politècnica de Cataluny1EEBE08019 Barcelon1Spain department of chemical Engineering Universidade Federal de Sao Carlos(UFSCAR)Sao CarlosBrazil

Gas-phase catalytic conversion of glycerol to value added chemicals was investigated over zinc-supported copper and nickel *** addition of aluminum in the support was also investigated in glycerol conversion and the results indicate an increase in the acidity and adsorption capacity for both copper and nickel *** and XRd analysis revealed Ni Zn alloy formation in the Ni/ZnO *** XRd patterns of the prepared Zn Al mixed oxide catalysts show the presence of Gahanite phase(ZnAl2O4).In addition,H2 chemisorption and TPR results suggest a strong metal-support interactions(SMSI)effect between Ni and Zn O *** supports Zn O and ZnAl(Zn/Al=0.5)were investigated in the glycerol conversion and they did not present *** supported on ZnO and ZnAl mixed oxide(Zn/Al=0.5)was active towards hydroxyacetone *** was active in the hydrogenolysis of glycerol both for c–c and c–O bonds cleavage of glycerol producing *** metal-support interactions(SMSI)between Ni and ZnO has a remarkable suppression effect on the methanation activity during the glycerol conversion.

关键词： Glycerol Hydrogenolysis dehydration Hydroxyacetone copper Nickel catalyst

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Modelling the biological performance of a side-stream membrane bioreactor using ASM1

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journal of Environmental Sciences 2004年第6期16卷 1020-1023页

作者： TIANKe-jun LIUXin-ai jIANGTao M.d.Kennedy j.c.Schippers P.A.Vanrolleghem MinistryofWaterResourcesofPRc Beijing100053China UNEScO-IHEInstituteforWaterEducation POBox30152601DADelftTheNetherlands BIOMATH GhentUniversityCoupureLinks653B-9000GentBelgium

Membrane bioreactors(MBRs) are attracting global interest but the mathematical modeling of the biological performance of MBRs remains very limited. This study focuses on the modelling of a side-stream MBR system using Activated Sludge Model No.1(ASM1), and comparing the results with the modelling of traditional activated sludge processes. ASM1 parameters relevant for the long-term biological behaviour in MBR systems were calibrated(i.e. Y H=0.72gcOd/gcOd, Y A=0.25gcOd/gN, b H=0.25 d -1, b A=0.080 d -1 and f P=0.06), and generally agreed with the parameters in traditional activated sludge processes, with the exception that a higher autotrophic biomass decay rate was observed in the MBR. A sensitivity analysis for steady state operation and dO dynamics suggested that the biological performance of the MBR system(the sludge concentration, effluent quality and the dO dynamics) are very sensitive to the parameters(i.e. Y H, Y A, b H, b A, μ maxH and μ maxA), and influent wastewater components(X I, S S, X S, S NH).

关键词： membrane bioreactor modelling parameter estimation

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IMPROVING THE SURFAcE PROPERTY OF Tc4 ALLOY BY LASER NITRIdING ANd ITS MEcHANISM

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Acta Metallurgica Sinica(English Letters) 2006年第2期19卷 151-156页

作者： Y.L. Yang G.j. Zhao d. Zhang c.S. Liu Gollege of Sdence Northeastern University Shenyang 110004 Ghina college of Material and Metallurgy Northeastern University Shenya g 110004 China

The mixing technology of laser and heated nitrogen was applied to improve the surface hardness of titanium alloy （ Tc4 ）. The samples were nitrided with laser power density of 6.S × 10^6SW. cm^-2, the scanning speed varioas from 100 to 500mm ·min^-1. The nitrogen gas was pre-heated to 300℃ to accelerate the nitriding process. Some interested samples were tested with XRd method （X-ray diffraction） to analyze the composition of nitrides, and the surface hardness of HV was measured. The results show that TiN and Ti2N were formed on the surface of Ti alloy with proper nitriding parameters, but TiN is the main composition. The surface hardness increased by three times, which is from the original value of 269to 794kg·mm^-2. The mechanism of the mixing technology is considered mainly of the activation of nitrogen by laser power and the pre-heated process which accelerated the nitriding process. The nitridation process can be considered as six steps given in detail. The result by analyzing the mechanism of improving the surface property of TiAl alloy shows the improvement of surface property due to two factors： the first reason is the result of laser annealing, and the second one is the formation of TiN.

关键词： laser nitridation surface property Ti alloy

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STUdY ON REdUcING THE cORE LOSS OF GRAIN ORIENTEd SILIcON STEEL ANd IMPROVING ITS AGING PROPERTY BY LASER NITRIdING TEcHNIQUE IN ATMOSPHERIc AMBIENT

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Acta Metallurgica Sinica(English Letters) 2005年第4期18卷 533-538页

作者： Y.L. Yang c.S. Liu F.j. Sun d. Zhang college of Science Northeastern University Shenyang 110004 China college of Material ＆ Metallurgy Northeastern University Shenyang 110004China

cW-cO2 laser nitriding technique was applied to improve the properties （such as aging property and the core loss） of grain oriented silicon steel. The samples were nitrided with regular space. Laser power density and scanning speed were chosen as 7.8×10^5W·cm^-2 and 100mm·min^-1. By some laser irradiation, Fe4N and Fe3N were formed in the nitrided zone. The nitrided samples were annealed at the temperatures ranged from 100 to 90℃. The core loss of some interested samples was tested. The results show that the core loss of the nitrided samples with different thickness of 0.23 and 0.30mm decreased by 14.9% and 9.4% respectively, and the aging property were improved up to 800℃. The mechanism of laser nitriding to improve the properties of grain oriented silicon steel is discussed.

关键词： laser nitriding grain oriented silicon steel sheet core loss aging property

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