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The integrated use of chemical insecticides and the entomopathogenic nematode, steinemema carpocapsae （Nematoda： steinernematidae）, for the control of sweetpotato whitefly, 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 james j. Mathers Phil Northing Anthony j. Prickett Keith f. A. Waiters Central science Laboratory Sand Hutton York YO41 1LZ UK

The integration of chemical insecticides and infective juveniles of the entomopathogenic nematode steinernema carpocapsae （Wesier）（Nematoda： steinernematidae）, to control second instars of the sweetpotato whitefly, Bemisia tabaci Gennadius （Hemiptera： Aleyrodidae） was investigated. Using a sand bioassay, the effects of direct exposure of s. carpocapsae for 24 h to field rate dilutions of four insecticides （spiromesifen, thiacloprid, imidacloprid and pymetrozine） on infectivity to Galleria mellonella larvae were tested. Although all chemicals tested, except spiromesifen, produced acceptable nematode infectivity rates, they were all significantly less than the water control. The effect of insecticide treatment （dry residues of spiromesifen, thiacloprid and pymetrozine and soil drench of imidacloprid） on the efficacy of the nematode against B. tabaci was also investigated. Nematodes in combination with thiacloprid and spiromesifen gave higher B. tabaci mortality （86.5% and 94.3% respectively） compared to using nematodes alone （75.2%） on tomato plants. There was no significant difference in B. tabaci mortality when using the chemicals imidacloprid, pymetrozine and spiromesifen in conjunction with nematodes compared to using the chemicals alone. However, using thiacloprid in combination with the nematodes produced significantly higher B. tabaci mortality than using the chemical alone. The integration of s. carpocapsae and these chemical agents into current integrated pest management programmes for the control of B. tabaci is discussed.

关键词： entomopathogenic nematode infectivity insecticide residue pest management

MICROsTRUCTURAL CHARACTERIsTICs AND MECHANICAL PROPERTIEs Of sPRAY fORMED HIGH sPEED sTEEL fOR WORK ROLL

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Acta Metallurgica sinica(English Letters) 2004年第4期17卷 548-553页

作者： C.D.Zhou j.f.fan H.R.Le Y.j.Lin D.s.sun j.G.Zhang Baosteel Technical Centre Shanghai 201900 ChinaBaosteel Technical Centre Shanghai 201900 ChinaBaosteel Technical Centre Shanghai 201900 ChinaBaosteel Technical Centre Shanghai 201900 ChinaBaosteel Technical Centre Shanghai 201900 ChinaBaosteel Technical Centre Shanghai 201900 China

The mechanical properties and microstructure characteristics of a high speed steel (Hss) for roll has been studied. As compared with the as-cast Hss, the spray-formed Hss have fine grain and segregation free microstructures. Carbides distribute uniformly. The morphology and types of the carbides in spray-formed Hss are different from those in as-cast Hss. The results of the high temperature tensile experiment show that, as to spray-formed Hss, there is a possibility of superplastic deformation in the range of 780-810℃.

关键词： spray forming high speed steel microstructure mechanical properties

si-Al COATING ON PURE MOLYBDENUM sUBsTRATE AND ITs CYCLIC OXIDATION BEHAVIOR

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Acta Metallurgica sinica(English Letters) 2004年第5期17卷 672-676页

作者： f.s.Liu j.L.Xu C.G.Zhou s.K.Gong H.B.Xu schoolofMaterialsscienceandEngineering BeijingUniversityofAeronauticsandAstronauticsBeijing100083China

The halide-activated pack cementation method is utilized to codeposit aluminum and silicon on Mo substrate. Emphasis is placed on the microstructure and elevated-temperature oxidation resistance of coatings. The results show that hexagonal Mo(si, Al)2 as a main phase and a little amount of the lower disilicide Mo5si3 was formed on Mo substrate through the halide-activated pack cementation method. The resultant si-Al coating on Mo substrate exhibits excellent cyclic oxidation resistance. The excellent cyclic oxidation resistance of the coatings is attributed to the formation of alumina on the coatings during the oxidation.

关键词： Mo(si Al)2 coating co-deposition cyclic oxidation resistance

Optimal use of mobile cooling units in a deep-level gold mine

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International journal of Mining science and Technology 2020年第4期30卷 547-553页

作者： H.j.van staden j.f.van Rensburg H.j.Groenewald Centre for Research and Continued Engineering Development North-West UniversityPretoria 0081South Africa

The south African gold mining sector remains a significant contributor to the country’s *** several challenges that hinder the realisation of south Africa’s full mineral potential,the sector’s sustainability and profitability can be enhanced through implementing operational improvement *** cooling units(MCUs)were identified as a potential focus area for operational *** are used as tertiary or in-stope cooling in hot underground *** this paper,a method was presented to characterise the performance of existing MCUs based on three key performance indicators(KPIs),namely,the wet-bulb temperature ratio(WTR),efficiency and *** strategies were then elected and implemented based on these *** implementation of this method in a south African gold mine attained a reduction in pumped water volumes,reduced operating costs through electricity cost savings and improvements in underground ventilation air temperatures.

关键词： Mobile cooling units Optimisation Mine cooling performance Electricity cost savings spot cooling

Experimental study on the wear evolution of different PVD coated tools under milling operations of LDX2101 duplex stainless steel

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Advances in Manufacturing 2023年第1期11卷 158-179页

作者： Vitor f.C.sousa francisco j.G.silva Ricardo Alexandre jose s.fecheira Gustavo Pinto Andresa Baptista IsEP-school of Engineering Polytechnic of PortoRua Dr.António Bernardino de Almeida4314200–072PortoPortugal INEGI-Driving science and Innovation Rua Dr.Roberto Frias4004200–465PortoPortugal TEandM-Technology Engineering and MaterialsS.A.Parque Industrial do TaveiroLotes 41-423045–504TaveiroPortugal

Duplex stainless steels are being used on applications that require,especially,high corrosion resistance and overall good mechanical properties,such as the naval and oil-gas exploration *** components employed in these industries are usually obtained by machining,however,these alloys have low machinability when compared to conventional stainless *** this work,a study of the wear developed when milling duplex stainless-steel,LDX 2101,is going to be presented and evaluated,employing four types of milling tools with different geometries and coatings,while studying the influence of feed rate and cutting length in the wear of these *** used have been provided with two and four flutes,as well as three different coatings,namely:TiAlN,TiAlsiN and *** cutting behavior of these tools was analyzed;data relative to the cutting forces developed during the process were obtained;and roughness measurements of the machined surfaces were *** tools were then submitted to scanning electron microscope(sEM)analysis,enabling the identification of the wear mechanisms that tools were subjected to when machining this material,furthermore,the early stages of these mechanisms were also *** this work was done with the goal of relating the machining parameters and cutting force values obtained,identifying,and discussing the wear patterns that were observed in the coating and tools after the milling tests,providing further information on the machining of these alloys.

关键词： Duplex stainless-steel Milling Tool coatings surface roughness Wear mechanisms

small Zeros of Additive forms in several Variables

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Acta Mathematica sinica,English series 1998年第1期14卷 57-66页

作者： j. s. Hwang Institute of Mathematics Academia Sinica Taipei Taiwan 11529 China

Let f（X） be an additive form defined by f（X）=f（x1. x2,…,xs）=σ1α1x1k+σα2x2k+…+σsαsxsk, where αo≠0 is integer, i=1, 2,…, s. In 1979, schmidt proved that if ε>0 then there is a large constant C（k, ε）... 详细信息

Let f（X） be an additive form defined by f（X）=f（xsub>1sub>. xsub>2sub>,…,xsub>ssub>）=σsub>1sub>αsub>1sub>xsub>1sub>sup>ksup>+σsub>αsub>sub>2sub>xsub>2sub>sup>ksup>+…+σsub>ssub>αsub>ssub>xsub>ssub>sup>ksup>, where αsub>osub>≠0 is integer, i=1, 2,…, s. In 1979, schmidt proved that if ε>0 then there is a large constant C（k, ε） such that for s≥C（k, ε） the equation f（X）=0 has a nontrivial integer solution in σsub>1sub>. σsub>2sub>,…σsub>ssub>, xsub>1sub>, xsub>2sub>…,xsub>ssub> satisfying σsub>isub>=±1 and |xsub>isub>|≤Asup>εsup>, i=1, 2.…,s where A=max|ai|. schmidt did not estimate this constant C（k. ε） since it would be extremely large. In this paper, we prove the following result: Theorem 1 If log A≤1/ε,then C（k,ε）≤max （2/ε,20）; if log A>1/ε,A is sufficiently larye and 1/2A≤5≤|asub>isub>|≤A,i=1. 2,…, s, then C（k,ε）≤csub>1sub>csub>2sub>sup>psup> and if the last condition is omitted, then C（k. ε）≤[4/ε]csub>1sub>csub>2sub>,where csub>1sub>={2k+1 for≤k≤11 [5ksup>2sup>log k] for k≥12, csub>2sub>=100csub>1sub>ksup>2sup>2sup>ksup>+csub>1sub>sup>2sup> and p=2[log 2csub>1sub>/ε]. We note that the inequality in the first case is sharp but not in the second case.

关键词： Additive form subset sums small zeros

ADVANCED OPTICAL TECHNIQUEs TO EXPLORE BRAIN sTRUCTURE AND fUNCTION

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journal of Innovative Optical Health sciences 2013年第1期6卷 1-15页

作者： L.sILVEsTRI A.L.ALLEGRA MAsCARO j.LOTTI L.sACCONI f.s.PAVONE European Laboratory for Nonlinear spectroscopy(LENs)University of florence Italy National Institute of Optics(INO-CNR) Sesto FiorentinoItaly Department of Physics University of FlorenceItaly International Center for Computational Neurophotonics-ICON foundation FlorenceItaly

Understanding brain structure and function,and the complex relationships bet ween them,is one of the grand challenges of contemporary *** to their fexiblity,optical techniques could be the key to explore this complex *** this manuscript,we briefly review recent adv ancements in optical methods applied to three main issues:anatomy,plasticity and *** describe novel implement ations of light-sheet microscopy to resolve neuronal anat-omy in whole fixed brains with cellular *** to liv ing samples,we show how real-time dynamics of brain rewiring can be visualized through two-photon microscopy with the spatial resolution of single synaptic *** plasticity of the injured brain can also be dissected through cut ting edge optical methods that specifically ablate single neuronal ***,we report how nonlinear microscopy in combination with novel voltage sensitive dyes allow optical registrations of action potential across a population of neurons opening promising prospective in understanding brain *** knowledge acquired from these complementary optical methods may provide a deeper comprehension of the brain and of its unique features.

关键词： Brain optical microscopy light sheet microscopy two-photon microscopy

A new oxidative pathway of nitric oxide production from oximes in plants

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Molecular Plant 2024年第1期17卷 178-198页

作者： Pedro Lopez-Gomez javier Buezo Marina Urra Alfonso Cornejo Raquel Esteban jorge fernandez de los Reyes Estibaliz Urarte Estefania Rodriguez-Dobreva Alejandro Chamizo-Ampudia Alejandro Eguaras sebastian Wolf Daniel Marino Victor Martinez-Merino jose f.Moran Institute for Multidisciplinary Research in Applied Biology(IMAB) Department of SciencesPublic University of Navarre(UPNA)Avda.de Pamplona 12331192 MutilvaSpain Institute for Advanced Materials and Mathematics(INAMAT2) Department of SciencesPublic University of Navarre(UPNA)Campus de Arosadia31006 PamplonaSpain Department of Plant Biology and Ecology University of the Basque Country(UPV/EHU)Sarriena s/nApdo.64448080 BilbaoSpain Center for Plant Molecular Biology(ZMBP) University of TubingenGeschwister-Scholl-Platz72074 TubingenGermany Institute of Natural Resources and Agrobiology of salamanca(IRNAsA) Department of Plant-Microorganism InteractionsSpanish National Research Council(CSIC)Cordel de Merinas40-5237008SalamancaSpain Department of Biochemistry Area of Molecular BiologyVeterinary FacultyUniversity of LeonCampus de Vegazanas/n.24071 LeonSpain

Nitric oxide(NO)is an essential reactive oxygen species and a signal molecule in *** several studies have proposed the occurrence of oxidative NO production,only reductive routes for NO production,such as the nitrate(NO_(3)^(-))-upper-reductase pathway,have been evidenced to date in land ***,plants grown axenically with ammonium as the sole source of nitrogen exhibit contents of nitrite and NO3−,evidencing the existence of a metabolic pathway for oxidative production of *** hypothesized that oximes,such as indole-3-acetaldoxime(IAOx),a precursor to indole-3-acetic acid,are intermediate oxidation products in NO *** detected the production of NO from IAOx and other oximes catalyzed by peroxidase(POD)enzyme using both 4-amino-5-methylamino-2′,7′-difluorescein fluorescence and *** stimulated the reaction,while superoxide dismutase inhibited ***,mouse NO synthase can also use IAOx to produce NO at a lower rate than *** provided a full mechanism for POD-dependent NO production from IAOx consistent with the experimental data and supported by density functional theory *** showed that the addition of IAOx to extracts from Medicago truncatula increased the in vitro production of NO,while in vivo supplementation of IAOx and other oximes increased the number of lateral roots,as shown for NO donors,and a more than 10-fold increase in IAOx dehydratase ***,we found that in vivo supplementation of IAOx increased NO production in Arabidopsis thaliana wild-type plants,while prx33-34 mutant plants,defective in POD33-34,had reduced *** data show that the release of NO by IAOx,as well as its auxinic effect,explain the superroot ***,our study reveals that plants produce NO utilizing diverse molecules such as oximes,POD,and flavins,which are widely distributed in the plant kingdom,thus introducing a long-awaited oxidative pathway to NO production in plants.T

关键词： ammonium oxidation auxin nitric oxide oxime peroxidase root phenotype

Boundary discontinuous fourier analysis of thick beams with clamped and simply supported edges via CUf

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Chinese journal of Aeronautics 2017年第5期30卷 1708-1718页

作者： f.G.CANALEs j.L.MANTARI faculty of Mechanical Engineering Universidad de Ingenieriay Tecnologia ( UTEC) Lima 15063 Peru Department of Mechanical Engineering University of New Mexieo Albuquerque 87131 USA

This paper presents an analytical solution for static analysis of thick rectangular beams with different boundary conditions. Carrera＇s Unified formulation（CUf） is used in order to consider shear deformation theories of arbitrary order. The novelty of the present work is that a boundary discontinuous fourier approach is used to consider clamped boundary conditions in the analytical solution, unlike Navier-type solutions which are restricted to simply supported *** equations are obtained by employing the principle of virtual work. The numerical accuracy of results is ascertained by studying the convergence of the solution and comparing the results to those of a 3D finite element solution. Beams subjected to bending due to a uniform pressure load and subjected to torsion due to opposite linear forces are considered. Overall, accurate results close to those of 3D finite element solutions are obtained, which can be used to validate finite element results or other approximate methods.

关键词： Analytical solution Beam Clamped fourier Unified formulation