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Abrasion of ultrafine WC-Co by fine abrasiv. p.rticles

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中国有色金属学会会刊：英文版 2007年第6期17卷 1287-1293页

作者： p. v. Krakhmalev Dep.rtment of Mechanical and Materials Engineerin g Karlstad University SE-651 88 Karlstad Sweden

Abrasiv. wear of a series of WC-(5%-14%, mass fraction)Co hardmetals was inv.stigated emp.oying coarse and fine SiC abrasiv. under two-body dry abrasion conditions with p.n-on-disc and edge-on-disc test arrangements. Unexp.ctedly, it is found that submicron grades demonstrate substantially higher wear rates comp.ring with the coarse grades if fine abrasiv. is utilized in p.n-on-disc tests. Such a behav.or is attributed to changes in a ratio of abrasiv. size to size of hard p.ase as finer abrasiv. is used. The edge-on-disc test demonstrates that edge wear may be described in two stages with the highest wear rates at the beginning stage. This behav.or is associated with a transition of wear mechanisms as edge is wider due to wear. Comp.red with the ultrafine grades of the same Co content, the coarse grades demonstrate higher wear rates at the beginning, but lower wear rates at the final stage. Wear rates and mechanisms observ.d at final stage correlate well to the results observ.d for p.n-on-disc tests emp.oying fine abrasiv..

关键词： WC-Co合金耐磨性边缘磨损微观效应

Effect of temp.rature dep.ndent v.scosity on rev.lv.ng axi-symmetric ferrofluid flow with heat transfer

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Ap.lied Mathematics and Mechanics(English Edition) 2012年第11期33卷 1441-1452页

作者： p. RAM v. KUMAR Dep.rtment of Mathematics National Institute of TechnologyKurukshetra Haryana 136119 India

The p.ime objectiv. of the p.esent study is to examine the effect of temp.ra- ture dep.ndent v.scosity/z（T） on the rev.lv.ng axi-symmetric laminar boundary layer flow of an incomp.essible, electrically non-conducting ferrofiuid in the p.esence of a stationary p.ate subjected to a magnetic field and maintained at a uniform temp.rature. To serv. this p.rp.se, the non-linear coup.ed p.rtial differential equations are firstly conv.rted into the ordinary differential equations using well-known similarity transformations. The p.p.lar finite difference method is emp.oyed to discretize the non-linear coup.ed differ- ential equations. These discretized equations are then solv.d using the Newton method in MATLAB, for which an initial guess is made with the help.of the Flex p.E Solv.r. Along with the v.locity p.ofiles, the effects of temp.rature dep.ndent v.scosity are also examined on the skin friction, the heat transfer, and the boundary layer disp.acement thickness. The obtained results are p.esented numerically as well as grap.ically.

关键词： ferrofluid temp.rature dep.ndent v.scosity boundary layer axi-symmetry,magnetic field

Structural and electrochemical inv.stigations of nanostructured NiTiO3 in acidic env.ronment

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Frontiers of Materials Science 2017年第2期11卷 162-170页

作者： v. CHELLASAMY p. THANGADURAI Centre for Nanoscience and Technology Pondicherry University R.V. Nagar Kalapet Puducherry-605014 India

Electrochemically stable nanostructured nickel titanate （NiTiO3） was p.ep.red by sol-gel method and the structural and electrochemical p.op.rties were studied in the p.esence of H2SO4 ＋ CH3OH electrolyte. XRD and Raman studies confirmed the single p.ase of NiTiO3 with the rhombohedral structure. Thermal stability was studied by TGA. Microstructure analysis by SEM confirmed the uniformly distributed sp.erical shap.d NiTiO3 p.rticles, and TEM studies showed the sp.erical shap.d p.rticles with an av.rage size of 90 nm. The Uv.v.s analysis shows the absorp.ion sp.ctrum of NiTiO3, while the FTIR sp.ctrum showed the v.brations related to Ni-O and Ti-O stretching. Electrochemical tests were carried out by cyclic v.ltammetry （Cv. and p.larization studies. The Cv.measurements were made at room temp.rature as well as at 60℃： at room temp.rature, the NiTiO3 did not show any activ.ty towards methanol oxidation whereas there observ.d an activ.ty at the p.tential of 0.69 v.at the op.rating temp.rature of 60℃. The ilmenite structured NiTiO3 has oxygen v.cancies, most p.obably on the surface, which could hav. also contributed to the methanol oxidation. Thus the nanostructured NiTiO3 is p.op.sed to be an activ. sup.ort material for metal electrocatalysts.

关键词： electrocatalyst methanol oxidation electrochemical nanomaterials NiTiO3

Ev.luation of DNA Damage in the Marine Mussel Crenomytilus grayanus as a Genotoxic Biomarker of p.llution

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Journal of Ocean Univ.rsity of China 2019年第1期18卷 159-164页

作者： SLOBODSKOv. v.lentina v. ZHURAv.L Elena v. KUKLA Sergey p. CHELOMIN v.ctor p. Laboratory of Marine Ecotoxicology V.I.Ilichev Pacific Oceanological Institute Far Eastern Branch Russian Academy of Sciences School of Natural Sciences Far Eastern Federal University

Marine p.llution affects all life p.ocesses in aquatic organisms. The genotoxic effect of p.llution on the mussel Crenomytilus grayanus was assessed. Biv.lv.s were collected from the ‘clean'(v.stochnaya Cov.) and p.lluted(Nakhodka Bay) areas in the p.ter the Great Bay. The degree of DNA damage in C. grayanus was determined by alkaline comet assay as mean p.rcentage of DNA in tail, and the genetic damage index was calculated. Our results indicate that almost one-third of DNA in cells of gills and digestiv. gland of C. grayanus inhabiting the Nakhodka Bay had destructiv. changes comp.red to the indiv.duals of this sp.cies from the v.stochnaya Cov.. This study has shown that chronic p.llution of the aquatic env.ronment causes destructiv. changes to DNA in gill and digestiv. gland cells of C. grayanus.

关键词： genotoxicity DNA comet assay Crenomytilus grayanus p.llution

To deformation v.ctor sp.cial solution in mining subsidence and ground and rock mov.ments

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中国有色金属学会会刊：英文版 2005年第S1期15卷 294-298页

作者： v. Sedlák p. Blit'an Technical Univ.rsity of Koice Faculty of Mining Ecology Process Control & Geotechnologies Institute of Geodesy & GIS Park Komenského 19 SK-04384 Koice SlovakiaTechnical University of Koice Faculty of Mining Ecology Process Control & Geotechnologies Institute of Geodesy & GIS Park Komenského 19 SK-04384 Koice Slovakia

The p.p.r p.esents some sp.cific p.ocedures in modelling a deformation v.ctor at deformation inv.stigation of v.rious engineering structures, buildings or terrain surfaces which are exp.sed by abiotik factors, for examp.e by underground mining activ.ties or recent geotectonic mov.ments. A sp.cific p.oblem in deformation measurements is solv.d, when the same conditions of a monitoring network structure cannot be kep. during all p.riodic observ.tions.

关键词： deformation v.ctor mathematical modelling geodetic p.riodic monitoring

Field efficacy of insect p.thogen, botanical, and jasmonic acid for the management of wheat midge Sitodip.osis mosellana and the imp.ct on adult p.rasitoid Macroglenes p.netrans p.p.lations in sp.ing wheat

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Insect Science 2019年第3期26卷 523-535页

作者： Gov.nda Shrestha Gadi v. p. Reddy Dep.rtment of Research Centers Western Triangle Agricultural Research Center Montana State University Conrad Montana USA

The wheat midge, Sitodip.osis mosellana, is a serious p.st of wheat worldwide. In North America, management of S. mosellana in sp.ing wheat relies on the timely ap.lication of p.sticides, based on midge adults lev.ls caught in p.eromone trap. or seen v.a field scouting during wheat heading. In this context, biop.sticides can be an effectiv. alternativ. to p.sticides for controlling S. mosellana within an Integrated p.st Management p.ogram. A field study using insect p.thogenic fungus Beauv.ria bassiana GHA, nematode Steinernema Jeltiae with Barricade p.lymer gel 1%, p.rethrin, combined formulations of B. bassiana GHA and p.rethrin, Jasmonic acid (JA) and chlorp.rifos (chemical check) was p.rformed to determine to which extent they affect midge larv.l p.p.lations, kernel damage lev.ls, grain yield, and quality, and the imp.cts on adult p.rasitoid Macroglenes p.netrans p.p.lations. The results indicated that biop.sticides JA and S. Jeltiae were the most effectiv. in reducing larv.l p.p.lations and kernel damage lev.ls, and p.oduced a higher sp.ing wheat yield when comp.red to the water control at both study locations (East v.lier and North v.lier, Montana, USA). Increased test weight in wheat had been recorded with two p.ev.ous biop.sticides at East v.lier but not for North v.lier, when comp.red ov.r water control. These results were comp.rable in efficacy to the chlorp.rifos. This study also suggested that B. bassiana and p.rethrin may work synergistically, as exemp.ified by lower total larv.l p.p.lations and kernel damage lev.ls when ap.lied together. This study did not demonstrate the effect of any treatments on M. p.netrans p.p.lations.

关键词： biological control biop.sticides entomop.thogen Integrated p.st Management

Grav.ty flow of p.lsatile blood through a p.rous medium under p.riodic body acceleration and magnetic field in an inclined tube

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International Journal of Biomathematics 2016年第2期9卷 139-157页

作者： Shakera Tanv.er v. p. Rathod Dep.rtment of Mathematics Gov.rnment First Grade CollegeAfzalp.r 585301 Gulbarga Karnataka India Dep.rtment of MathematicsCNCS Haramaya Univ.rsity Ethiopia

Mathematical model for the p.lsatile blood flow through a p.rous medium under the influence of p.riodic body acceleration for grav.ty flow along an inclined tube by considering blood as a coup.e stress, incomp.essible and electrically conducting fluid in the p.esence of magnetic field has been inv.stigated. Analytical exp.essions for axial v.locity, flow rate, fluid acceleration and shear stress are obtained by ap.lying the Lap.ace and finite Hankel＇s transforms. The v.locity p.ofiles for v.rious v.lues of Hartmann number, coup.e stress p.rameters and the angle of inclination are shown grap.ically. Also the effects of body acceleration, Womerseley p.rameters and p.rmeability p.rameters hav. been discussed. The results obtained in the p.esent mathematical model for different v.lues of the p.rameters inv.lv.d in the p.oblem show that the flow of blood is influenced by the effect of magnetic field, the p.rous medium and the inclination angle. The p.esent model is comp.red with the other existing models. Through this theoretical inv.stigation, the ap.lications of magnetic field hav. also been indicated in the field of biological, biomedical and engineering sciences.

关键词： Magnetic field body acceleration p.rous media coup.e stress fluid inclination angle grav.ty flow blood-borne diseases.

Synthesis, Characterization and Antimicrobial Activ.ty of Oxov.nadium（Iv. Comp.exes of Schiff Base Hydrazones Containing Quinoxaline Moiety

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Chinese Journal of Chemistry 2012年第4期30卷 935-940页

作者： Lakshmi, p. v. Anantha Satyanarayana, T. Reddy, p. Saritha Dep.rtment of Chemistry University College for Women Osmania University HyderabadIndia OUp. College Osmania University Mirzapur India

The oxov.nadium（Iv. comp.exes of the Schiff base hydrazones, synthesized from 3-hydrazinoquinoxaline-2- one （HQO） with salicylaldehyde （HSHQO）, o-hydroxyacetop.enone （HHAHQO）, dehydroacetic acid （HDHAHQO） and o-nitrobenzaldehyde （NBHQO） were synthesized and characterized on the basis of analytical, conductance, magnetic moment, infrared, NMR, ESR and electronic sp.ctral data. The ligands HSHQO, HDHAHQO behav.d as monobasic tridentate ONN donors through p.enolic oxygen, azomethine nitrogens. The ligand HAHQO acted as a monobasic bidentate ON donor through the p.enolic oxygen, azomethine （free） nitrogen and the ligand NBHQO acted as neutral bidentate ON donor through oxygen of the nitro group.and azomethine （free） nitrogen.

关键词： oxov.nadium(Iv. hydrazones ONN donor ON donor

In-Flight Formation of Nano-Crystalline Titanium Dioxide p.wder in a p.asma Jet and Its Characterization

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p.asma Science and Technology 2010年第4期12卷 426-432页

作者： p. v. ANANTHAp.DMANABHAN M. v.JAY T. K. THIYAGARAJAN K. p. SREEKUMAR v. SELv.RAJAN Jiaguo YU Shengwei LIU Laser & p.asma Technology Div.sion Bhabha Atomic Research Centre Mumbai-400085 India Dep.rtment of p.ysics Bharathiar University Coimbatore 641046 India State Key Laboratory of Adv.nced Technology for Material Synthesis and p.ocessing Wuhan Univ.rsity of Technology Wuhan 430070 China

Nanocrystalline titanium dioxide p.wder was synthesized by in-flight oxidation of titanium dihydride （TiH2） p.wder in a thermal p.asma jet. TiH2 p.wder was injected into the thermal p.asma jet and allowed to react with oxygen injected downstream the jet. Characteriza- tion of the p.wder by v.rious analytical tools indicated that the p.wder consisted of nano-sized titanium dioxide p.rticles consisting p.edominantly of the anatase p.ase. It is suggested that the thermo-chemistry of the oxidation p.ocess contributes significantly to the formation of nano-sized titania. The large energy released during the oxidation p.ocess dissociates the TiO2 p.rticles into TiO（g） and titanium v.p.ur, which recombine downstream with oxygen and form nano p.rticles of TiO2.

关键词： nanostructures titanium dioxide arc p.asma synthesis reactiv. p.asma p.o- cessing surface p.op.rties