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Quality control of the parasitoid wasp Trichogramma brassicae (Hymenoptera: Trichogrammatidae) over 45 generations of rearing on Sitotroga cerealella

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Insect Science 2021年第1期28卷 180-190页

作者： Ehsan ghaemmaghami Yaghoub Fathipour Abdoolnabi Bagheri Ali Asghar Talebi gadi v.P.reddy Department of Entomology Faculty of AgricultureTarbiat Modares UniversityTehranIran Plant Protection Research Department Hormozgan Agricultural and Natural Resources Research and Education CenterAgricultural Research Education and Extension Organization(AREEO)Bandar AbbasIran USDA-ARS-Southern Insect Pest Management Research Unit StonevilleMississippiUSA

Trichogramma brassicae(Bezdenko)is an important biological control agent that has been used widely against many lepidopteran ***,colonies of Trichogramma are mass reared on factitious hosts such as Sitotroga cerealella(Olivier)over many *** this study,we evaluated the quality and performance of a colony of *** that had been reared for over 45 generations(g)using two-sex life table parameters and parasitism *** found that female adult longevity was significantly different among sequential generations,ranging from 5.58±2.5 d(at g5)to 3.75±1.42 d(at g45).However,no significant difference was found in male adult longevity among different *** female wasps survived longer until the 15th gener・ation,they allocated more days for egg laying at g5 and *** highest values of gross reproductive rate(gRR),net reproductive rate(7.),intrinsic rate of increase(r),finite rate of increase(λ)and mean generation time(T)were found in g5 and gIO,which also showed significantly higher *** significant difference in the finite parasitism rate(co)was found among generations up to *** results suggest that *** wasps held under continuous laboratory rearing can be used successfully in biological control programs until the 15th generation without any loss of quality or ***,laboratory mass rearing colonies declined in quality after 15 generations and we suggest that they should be rejuvenated regularly by adding field-collected parasitoids periodically.

关键词： biological control generation-dependent demography mass rearing parasitism rate Trichogramma brassicae

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Improvement of Microstructure and Mechanical Behavior of gas Tungsten Arc Weldments of Alloy C-276 by Current Pulsing

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Acta Metallurgica Sinica(English Letters) 2015年第2期28卷 208-215页

作者： M.Manikandan N.Arivazhagan M.Nageswara Rao g.Madhusudhan reddy School of Mechanical and Building Sciences VIT University Defence Metallurgical and Research Laboratory

Superalloy C-276 is known to be prone to hot cracking during fusion welding by gas Tungsten Arc method. Microsegregation occurring during cooling of fusion zone with consequent appearance of topologically close-packed phases P and IX has been held responsible for the observed hot cracking. The present work investigated the possibility of suppressing the microsegregation in weldments by resorting to current pulse. Weldments were made by continuous current gas tungsten arc welding and pulsed current gas tungsten arc welding using ERNiCrMo-4 filler wire. The weld joints were studied with respect to microstructure, microsegregation, and mechanical properties. Optical microscopy and scanning electron microscopy were employed to study the microstructure. Energy-Dispersive X-ray Spectroscopy was carried out to evaluate the extent of microsegregation. Tensile testing was carried out to determine the strength and ductility. The results show that the joints fabricated with pulsed current gave rise to narrower welds with practically no heat affected zone, a refined microstructure in the fusion zone, reduced microsegregation, and superior combination of mechanical properties.

关键词： Alloy C-276 Pulsed current gas tungsten arc welding Microsegregation

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Microstructure and corrosion behaviour of gas tungsten arc welds of maraging steel

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Defence Technology（防务技术） 2015年第1期11卷 48-55页

作者： g.MADHUSUDHAN reddy K.SRINIvASA RAO Defence Metallurgical Research Laboratory Department of Metallurgical Engineering Andhra University

Superior properties of maraging steels make them suitable for the fabrication of components used for military applications like missile covering, rocket motor casing and ship hulls. Welding is the main process for fabrication of these components, while the maraging steels can be fusion welded using gas tungsten arc welding(gTAW) process. All these fabricated components require longer storage life and a major problem in welds is susceptible to stress corrosion cracking(SCC). The present study is aimed at studying the SCC behaviour of MDN 250(18% Ni) steel and its welds with respect to microstructural changes. In the present study, 5.2 mm thick sheets made of MDN 250 steel in the solution annealed condition was welded using gTAW process. Post-weld heat treatments of direct ageing(480 C for 3 h), solutionizing(815 C for 1 h) followed by ageing and homogenizing(1150 C for 1 h) followed by ageing were carried out. A mixture of martensite and austenite was observed in the microstructure of the fusion zone of solutionized and direct aged welds and only martensite in as-welded condition. Homogenization and ageing treatment have eliminated reverted austenite and elemental segregation. Homogenized welds also exhibited a marginal improvement in the corrosion resistance compared to those in the as-welded, solutionized and aged condition. Constant load SCC test data clearly revealed that the failure time of homogenized weld is much longer compared to other post weld treatments, and the homogenization treatment is recommended to improve the SCC life of gTA welds of MDN 250 Maraging steel.

关键词： 18% Ni maraging steel gas tungsten arc welding Post weld heat treatment Solutionising Ageing treatment Pitting corrosion Stress corrosioncracking (SCC)

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Friction welding of AA6061 to AISI 4340 using silver interlayer

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Defence Technology（防务技术） 2015年第3期11卷 292-298页

作者： SURESH D.MESHRAM g.MADHUSUDHAN reddy Defence Metallurgical Research Laboratory

The present work pertains to the study on joining of AA6061 and AISI 4340 through continuous drive friction welding. The welds were evaluated by metallographic examination, X-ray diffraction, electron probe microanalysis, tensile test and microhardness. The study reveals that the presence of an intermetallic compound layer at the bonded interface exhibits poor tensile strength and elongation. Mg in AA6061 near to the interface is found to be favourable for the formation and growth of Fe2Al5 intermetallics. Introduction of silver as an interlayer through electroplating on AISI 4340 resulted in accumulation of Si at weld interface, replacing Mg at AA6061 side, thereby reducing the width of intermetallic compound layer and correspondingly increasing the tensile strength. Presence of silver at the interface results in partial replacement of Fe-Al based intermetallic compounds with Ag-Al based compounds. The presence of these intermetallics was confirmed by X-ray diffraction technique. Since Ag-Al phases are ductile in nature, tensile strength is not deteriorated and the silicon segregation at weld interface on AA6061 in the joints with silver interlayer acts as diffusion barrier for Fe and further avoids formation of Fe-Al based intermetallics. A maximum tensile strength of 240 MPa along with 4.9% elongation was obtained for the silver interlayer dissimilar metal welds. The observed trends in tensile properties and hardness were explained in relation to the microstructure.

关键词： AISI 摩擦焊接金属间化合物层 X-射线衍射技术银焊接界面博士夹层

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Transient analysis of diffusive chemical reactive species for couple stress fluid flow over vertical cylinder

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Applied Mathematics and Mechanics(English Edition) 2013年第8期34卷 985-1000页

作者： H.P.RANI g.J.reddy C.N.KIM Department of Mathematics National Institute of Technology Department of Mechanical Engineering College of Advanced Technology (Industrial Liaison Research Institute) Kyung Hee University

The unsteady natural convective couple stress fluid flow over a semi-infinite vertical cylinder is analyzed for the homogeneous first-order chemical reaction effect. The couple stress fluid flow model introduces the length dependent effect based on the material constant and dynamic viscosity. Also, it introduces the biharmonic operator in the Navier-Stokes equations, which is absent in the case of Newtonian fluids. The solution to the time-dependent non-linear and coupled governing equations is carried out with an unconditionally stable Crank-Nicolson type of numerical schemes. Numerical results for the transient flow variables, the average wall shear stress, the Nusselt number, and the Sherwood number are shown graphically for both generative and destructive reactions. The time to reach the temporal maximum increases as the reaction constant K increases. The average values of the wall shear stress and the heat transfer rate decrease as K increases, while increase with the increase in the Sherwood number.

关键词： couple stress fluid chemical reaction natural convection vertical cylinder,finite difference method

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Mechanical properties of Ni_(0.83)Co_(0.15)Cu_(0.02)Fe_(1.9)O_(4-δ)+PbZr_(0.52)Ti_(0.48)O_(3)particulate composites by composite oscillator technique and the correlation with the results of magnetoelectric properties

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Journal of Advanced Ceramics 2012年第4期1卷 317-326页

作者： M.venkata RAMANA M.Penchal reddy N.Ramamanohar reddy B.S.MURTY K.v.SIvA KUMAR Shenhua SONg Shenzhen Key Laboratory of Advanced Materials Department of Materials Science and EngineeringShenzhen Graduate SchoolHarbin Institute of TechnologyShenzhen 518055China Department of Physics Changwon National UniversityChangwonRepublic of Korea Ceramic Composite Materials Laboratory Department of PhysicsSri Krishnadevaraya UniversityAnantapur 515003India Nanotechnology Laboratory Department of Metallurgical and Materials EngineeringIndian Institute of TechnologyChennai 600036India

The xNi_(0.83)Co_(0.15)Cu_(0.02)Fe_(1.9)O_(4-δ)+PbZr_(0.52)Ti_(0.48)O_(3)(PZT)particulate magneto ferroelectric composites with x=0,0.1,0.2,0.3,0.4,0.5 and 0.6 mole fraction were prepared by conventional ceramic double sintering *** presence of two phases(perovskite structure of ferroelectric phase and spinal structure of ferromagnetic phase)was confirmed by X-ray *** magnetoelectric(ME)property of the particulate composites was determined at room temperature as a function of intensity of magnetic *** temperature variation of the longitudinal modulus(L)and the internal friction(Q−1)of these particulate composites at 104.3 kHz was studied in the wide temperature range 30-420℃.The temperature variation of the longitudinal modulus in each composition of these particulate composites showed two abrupt *** minimum coincided with the ferroelectric-paraelectric Curie transition temperature(θE)and the other with the ferromagnetic-paramagnetic Curie transition temperature(θM).The internal friction measurement also showed two sharp peaks in each composition corresponding to those temperatures where the minima were noticed in the temperature variation of the longitudinal modulus behaviour.

关键词： X-ray diffraction magnetoelectric effect piezoelectric coefficient internal friction Curie transition temperature

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Joining of AZ91 Mg alloy and Al6063 alloy sheets by friction stir welding

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Journal of Magnesium and Alloys 2018年第1期6卷 71-76页

作者： B.Lakshmana Prasad g.Neelaiah M.gopi Krishna S.v.v.Ramana K.Sai Prakash g.Sarika g.Pradeep Kumar reddy Ravikumar Dumpala B.Ratna Sunil Department of Mechanical Engineering Rajiv Gandhi University of Knowledge Technologies(AP-IIIT)Nuzvid 520201India Department of Mechanical Engineering Vignana Bharathi Institute of TechnologyHyderabad 501301India Department of Mechanical Engineering Visvesvaraya National Institute of TechnologyNagpur 440010India

In the present work,the effect of process parameters on joining of AZ91 Mg alloy and Al6063 aluminum alloy sheets during friction stir welding(FSP)was studied.A successful joint was achieved at 1100 *** rotational speed and 25 mm/min tool travel *** of tool rotational speed and tool travel speed has observed a profound effect on the material flow mechanisms at the nugget *** the microstructural studies,the joint formation was observed as mainly due to mechanical mixing of the *** level of metallurgical continuity at the nugget zone was observed as poor and a sharp interface at the joint was *** microhardness measurements across the weld joint also revealed the lack of establishment of a perfect metallurgical bonding.X-ray diffraction analysis of weld zone showed presence of both magnesium and *** from the preliminary observations,it can be understood that the joining of AZ91 Mg alloy and Al6063 alloy can be achieved by FSP;however,complex issues in material mixing still need further investigations.

关键词： Friction stir welding Dissimilar joints Magnesium Aluminum Nugget zone

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Bemisia tabaci Phylogenetic groups in India and the Relative Transmission Efficacy of Tomato leaf curl Bangalore virus by an Indigenous and an Exotic Population

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Journal of Integrative Agriculture 2012年第2期11卷 235-248页

作者： R v Chowda-reddy M Kirankumar Susan E Seal v Muniyappa girish B valand M R govindappa John Colvin Agriculture Health and Environment GroupNatural Resources InstituteUniversity of Greenwich at MedwayChatham MaritimeKentME4 4TBUnited Kingdom Southern Crop Protection and Food Research Centre London-N5V 4T3Canada Department of Plant Pathology University of Agricultural SciencesBangalore-560 065India Department of Plant Pathology Gujarat Agricultural UniversityAnand 388110GujaratIndia

Bemisia tabaci adults from various host-plant species were collected from 31 regions across India.266 *** samples were first screened by RAPD-PCR to examine molecular variability and to select individuals with different ***-plant and region of collection were then used to select 25 individuals for PCR amplification and sequencing of their partial mitochondrial cytochrome oxidase subunit one（mtCOI）*** comparisons with mtCOI consensus sequences showed that the majority of these samples had 〈3.5% sequence divergence from groups currently termed Asia I,Asia II-5,Asia II-7,and Asia *** biotype-B *** from India clustered into the Middle East-Asia Minor 1 group.A new group of *** from Coimbatore,collected from pumpkin,was related most closely to the Asia I group（6.2% sequence divergence from the consensus Asia I sequence）.To increase our understanding of the epidemiology of tomato leaf curl disease（ToLCD）and the key *** genetic groups involved in virus spread,the indigenous Asia I and the exotic biotype-B population from South India were used to carry out transmission experiments using Tomato leaf curl Bangalore virus（ToLCBv）.The acquisition access periods（AAP）,inoculation access periods（IAP）,latent periods（LP）,and ToLCBv transmission efficiencies of the two populations were compared and the biotype-B had the more efficient transmission *** results are discussed in relation to recent changes in the epidemiology of tomato leaf curl disease in South India.

关键词： begomoviruses mitochondrial cytochrome oxidase whitefly Bemisia tabaci virus-vector relationships epidemiology

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Schottky barrier parameters and structural properties of rapidly annealed Zr Schottky electrode on p-type gaN

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Journal of Semiconductors 2017年第6期38卷 44-51页

作者： v.Rajagopal reddy B.Asha Chel-Jong Choi Department of Physics Sri Venkateswara University School of Semiconductor and Chemical Engineering Semiconductor Physics Research Center (SPRC)Chonbuk National University

The Schottky barrier junction parameters and structural properties of Zr/p-gaN Schottky diode are explored at various annealing *** analysis showed that the barrier height（BH）of the Zr/pga N Schottky diode increases with annealing at 400°C（0.92 ev（I–v）/1.09 e v（C–v））compared to the asdeposited one（0.83 ev（I–v）/0.93 ev（C–v））.However,the BH decreases after annealing at 500°***,at different annealing temperatures,the series resistance and BH are assessed by Cheung’s functions and their values ***,the interface state density（NSS/of the diode decreases after annealing at 400°C and then somewhat rises upon annealing at 500°*** reveals that the maximum BH is obtained at 400°C,and thus the optimum annealing temperature is 400°C for the *** XPS and XRD analysis revealed that the increase in BH may be attributed to the creation of Zr–N phases with increasing annealing up to 400°*** BH reduces for the diode annealed at 500°C,which may be due to the formation of ga–Zr phases at the *** AFM measurements reveal that the overall surface roughness of the Zr film is quite smooth during rapid annealing process.

关键词： zirconium Schottky contacts p-type gaN electrical characteristics energy distribution curves X-ray photoelectron spectroscopy X-ray diffraction

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Breeding, introgression and inheritance of delayed gland morphogenesis trait from gosspium bickii into upland cotton germplasm

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Chinese Science Bulletin 2004年第23期49卷 2470-2476页

作者： reddy Naganagouda College of Agriculture and Biotechnology Zhejiang University Hang- zhou 310029 China

A tri-specific hybrid with delayed pigment gland morphogenesis was obtained by crossing the amphi- diploid of (g. arboreum×g. bickii) F1 and an upland cotton germplasm with pigment gland genotype of gl2gl2gl3gl3. The tri-specific hybrid was a typical interspecific hybrid with high sterile, and the chromosome configuration at meiosis MI of PMC was 2n = 52 = 41.04Ⅰ+ 4.54Ⅱ + 0.57Ⅲ + 0.04. The crossover value of bivalent was 1.19. Two fertile plants with objective character were obtained in BC8 population by continuously backcrossing with gl2gl2gl3gl3 as recurrent parent to the tri-specific hybrid, and a new upland cotton germplasm, named ABH-0318, with delayed pigment gland morphogenesis trait was developed through selfing and screening. The pigment gland trait of ABH-0318 was stable, and there were almost no pigment glands observed in the dormant seeds, although there were a few pigment glands confined to cotyledon edges, and the gossypol content in the dormant seeds was 0.017% only, being a typical low gossypol cotton type. However, a large quantity of pigment glands emerged in cotyledons and other main organs of plant after seed germination, and the gossypol contents in the upper parts of the plant were similar to that of ordinary glanded cotton types. genetic analysis demonstrated that the delayed pigment gland morphogenesis trait of this germplasm was controlled by the interaction of the genes located in two pig- ment gland loci, gl2 and gl3. Among them, the gene located in locus of gl2, derived from ***, was dominance to up- land cotton pigment gland alleles, gl2 and gl2 , but was reces- sive epistatic to another glanded gene gl3, which was named gl2 temporarily. While the gene located in the locus of gl3 b was a recessive gene come from upland cotton.

关键词：基因渗入现象 gosspium bickii 陆地棉色素腺棉子酚种间杂种

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