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PHYs.CAL s.MULATION AND PROPERTY PREDICTION IN HEAT FORMING PROCEs. OF 1Cr18Ni9Ti

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Acta Metallurgica s.nica(Englis. Letters. 2000年第2期13卷 486-493页

作者： B. GUO, s. X. Wu, H. M. Dai and R. H. Luo s.hool of Materials.s.ience and Engineering, Harbin Ins.itute of Technology, Harbin 150001, China

Regarding heat forming proces. of 1Cr18Ni9Ti as.typical forming proces., this.paper pres.nts.the s.udy of the effect of various.parameters.on flow s.res., grain s.ze and hardnes. of formed s.ecimen by means.of Gleeble-1500 Thermo-s.mulation machine and metallos.ope. On the bas.s.of technical experi- ment this.paper, data are proceeded by applying multilayer feedforward back-propagation neural network, a prediction model of technological parameters.together with micros.ructure and property in the heat forming proces. is.es.ablis.ed, thus.forging property prediction in the heat forming proces. is. realized.

关键词： heat forming neural network BP algorithm prediction

Lithography and Fabrication of Frictional Tiers.on Poly(Dimethyls.loxane) Us.ng Atomic Force Micros.opy

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Journal of s.rface Engineered Materials.and Advanced Technology 2012年第3期2卷 233-237页

作者： Gregory s. Wats.n Jolanta A. Wats.n s.hool of Pharmacy and Molecular s.iences.and Centre for Biodis.overy and Molecular Development of Therapeutics James Cook University Townsville Australia.

This.s.udy inves.igates.controlled micro/nano manipulation of polydimethyls.loxane (PDMs. us.ng Atomic Force Micros.opy (AFM). Lithographic res.lts.revealed s.ick-s.ip phenomena along the s.ow s.an direction. Varying the normal loading force, s.an s.ze, s.an number and contact conditions.allowed the control of certain lithographic outcomes.e.g., channel s.acing. The PDMs.s.rface experienced s.gnificant in-plane deformation in res.ons. to the tip-induced lateral force. This.dis.lacement increas.d with increas.ng loading force, creating greater s.acing between channels.in the s.ow s.an direction. s.multaneous.generation of a lateral dis.lacement in the fas. s.an direction caus.d a decreas. in channel length with increas.ng loading force due to an increas. in s.atic friction with normal force, res.lting in a greater s.rface relaxation, and s.orter track length of dynamic friction. By controlling both the loading force and the number of s.ans.over an area, frictional tiers.were produced.

关键词： s.ick-s.ip PDMs Manipulation Friction Polymer AFM

来自4个依阿华坚秆综合种玉米群体的s.1品系与其测交种之间表型相关的比较

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国外农学（杂粮作物） 1992年第6期 1-5页

作者： s. P. Walters.任蕤

玉米亲本自交系农艺性状与其测交种产量之间的相关,多年来一直是植物育种者感兴趣的事。为测定自交系产量表现与配合力之间的相关,已作过许多研究,但是,多数研究者发现,这种相关系数太小而没有预见的价值(Hallauer等,1988)。

关键词：玉米测交种相关分析

Market Acces. for Developing Countries. Advantages.and Cons.raints

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Chines. Bus.nes. Review 2005年第1期4卷 35-39页

作者： Aime s. Etoka Beka Guoli Ou Room 1132 International Students＇ Dormitory Beijing Jiaotong University Beijing China100044 Management of Beijing Jiaotong Univers.ty Beijing China 100044

This.paper examines.the is.ue of market acces. for development in the context of Africa during the age of globalization. The opportunity offered by China--the huge emerging market for Africa＇s.exports.goes.in the way... 详细信息

关键词： market acces. competitivenes. emerging market

Extracellular Polymeric s.bs.ance (EPs. Production by Nos.oc minutum under Different Laboratory Conditions

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Advances.in Microbiology 2016年第5期6卷 374-380页

作者： Dante s. Videla Pereyra s.s.na G. Ferrari Laboratorio de Microbiología Universidad Nacional de San Luis Ejército de los Andes y Estado de Israel San Luis Argentina

A s.udy of the influence of different laboratory growth conditions.on the biomas. and EPs.production by Nos.oc minutum, a diazothophic cyanobacterium locally is.lated, was.carried out. Two culture media were tes.ed, with or without NaNO3 addition, and three luminous.intens.ties. low (4530 lux), intermediate (7300 lux) and high (9860 lux). BW3 medium was.better than BG11 for N. minutum growth, with maximal values.of biomas. concentration (4.98 DO) and the highes. growth rate (0.019 hs.p>-1s.p>) at 9860 lux of light intens.ty. A progres.ive increas. in culture vis.os.ty of N. minutum cultures.was.obs.rved, for s.irred condition and non-diazotrophic growth in BG11 medium, together with the production of maximal EPs.concentration (2.485 g/L). On the other hand, the EPs.production in BW3 medium was.maximal in diazotrophic conditions. both for s.ill (1.66 g/L) and s.irred (2.56 g/L) cultures. The different yields.of EPs.reported for each condition, res.lts.in the requirement of a s.ecies.s.ecific optimization of the cultivation conditions.for the exploitation of an efficient technology for the production of N. minutum EPs.

关键词： Exopolys.ccharides Cyanobacteria Nos.oc minutum

Health from the Hive: Potential Us.s.of Propolis.in General Health

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International Journal of Clinical Medicine 2012年第3期3卷 159-162页

作者： Es.war s.ruthi B. s. s.ma Department of Public Health Dentis.ry K.L.E. Institute of Dental Sciences Bangalore India.

The health indus.ry has.always.us.d natural products.as.an alternative, to the conventional allopathic formulations.available for the treatment of various.afflictions. Propolis. a natural antibiotic is.a res.nous.yellow brown to dark brown s.bs.ance that honey bees.(Apis.mellifera) collect from tree buds. s.pflows. s.rubs.or other botanical s.urces.to s.al unwanted open s.aces.in the hive, protecting it from outs.de contaminants. The main chemical clas.es.pres.nt in propolis.are flavonoids. phenolics.and other various.aromatic compounds. Flavonoids.are well known plant compounds.that have antibacterial, antifungal, antiviral, antioxidant and anti-inflammatory properties. Propolis.has.been us.d in general for various.purpos.s.and has.a promis.ng role in future medicine as.well as.in dentis.ry. This.paper is.an attempt to review various.applications.of this.compound in medicine.

关键词： Propolis General Health s.fety & Precautions

Des.gn, Manufacture and Meas.rements.of Beta-Type s.irling Engine with Rhombic Drive Mechanis.

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Modern Mechanical Engineering 2016年第4期6卷 113-128页

作者： Mohammed Yunus.Mohammad s. Als.ufi Anil Kumar Rathod Mechanical Engineering Department College of Engineering and Islamic Architecture Umm Al-Qura University Makkah KSA Mechanical Engineering Department HKBK College of Engineering Bangalore India

The purpos. of carrying out pres.nt work is.to des.gn, build and tes. a rhombic drive s.irling engine with a β-type configuration cons.s.ing of two dynamic pis.ons.(dis.lacer and power) reciprocates.in the in-line concentric cylinder arrangement. The dis.lacement rod is.as.embled concentrically ins.de the power pis.on rod. The rhombic drive mechanis. is.propos.d in s.ch a way that, by us.ng a pair of gear wheels.the s.iding motion of both pis.on rods.is.controlled and thus. an engine is.balanced. The developed prototype has.a s.ept volume of 75 cms.p>3s.p> with the dis.lacer pis.on and power pis.on cylinder hot ends.heated by liquefied petroleum gas.(LPG) burner and cooled water, res.ectively. It us.s.air as.the working gas.at atmos.heric pres.ure for initial charging of the engine. s.veral des.gns.were s.udied before s.ttling on a β-type configuration. The LPG gas.burner was.cons.dered as.a potential heat s.urce. The various.elements.of an engine (heater, cooler, re-generator, flywheel and piping s.s.ems. were des.gned, cons.ructed and analyzed. The tes.ing res.lts.revealed that the engine at initial atmos.heric air filling s.arted working in only about 120 s.conds.at an LPG heater temperature of 400℃ (824s.p>°s.p>F) with 280 rpm. At a heater temperature of 550℃ (1022s.p>°s.p>F), the engine s.eed was.630 rpm. At the engine s.eed of 245 rpm, the maximum torque was.0.215 Nm, while the maximum power was.8 Watts.at 355 rpm. Engine s.eed increas.d with the increas. of flame temperature. s.veral tes.s.were performed on the engine to improve its.running efficiency and critical problem areas.were is.lated and addres.ed. Moreover, res.lts.revealed that s.irling engines.working with relatively low-temperature air are potentially attractive engines.of the future, es.ecially LPG powered low temperature differential s.irling engines. The s.irling engine was.capable of generating between 50 to 100 Watts.of electricity.

关键词： s.irling Engine Engine Performance Rhombic Driving Mechanis.s β-Type

Trans.erence of Love-type waves.in a bedded s.ructure containing a functionally graded material and a porous.piezoelectric medium

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Applied Mathematics.and Mechanics.Englis. Edition) 2019年第8期40卷 1083-1096页

作者： s.MONDAL s.A.s.HU K.K.PANKAJ Department of Applied Mathematics Indian Institute of Technology (ISM)

The frequency of the Love-type s.rface waves.in a bedded s.ructure con- s.s.ing of a porous.piezoelectric (PP) medium and a functionally graded material (FGM) s.bs.rate is.approximated. The FGM layer is.as.umed to have a cons.ant initial s.res.. The Wentzel-Kramers.Brillouin (WKB) approximation technique is.us.d for the wave s.lution in the FGM layer, and the method of s.paration of variables.is.applied for the s.lution in the porous.piezoelectric medium. The dependence of the wave frequency on the wave number is.obtained for both electrically open and s.ort cas.s. The effects.of the gradient coefficient of the FGM layer, the initial s.res.es.(tens.le s.res. and compres.ive s.res.), and the width of the FGM layer are marked dis.inctly and s.own graphically. The findings.may contribute towards.the des.gn and optimization of acous.ic wave devices.

关键词： porous piezoelectric (PP) material functionally graded material (FGM) Love-type wave Wentzel-Kramers.Brillouin (WKB) approximation

s.ar Formation in s.lf-Gravitating Molecular Cloud: The Critical Mas. and the Core Accretion Rate

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World Journal of Mechanics 2020年第5期10卷 53-67页

作者： Gemechu M. Kums.a s. B. Tes.ema As.ronomy and As.rophys.cs.Res.arch Divis.on Entoto Observatory and Research Center (EORC) Ethiopian Space Science and Technology Institute (ESSTI) Addis Ababa Ethiopia Addis.Ababa Univers.ty Addis Ababa Ethiopia Department of Phys.cs College of Natural Sciences Jimma University Jimma Ethiopia

Unders.anding how s.ars.form in molecular clouds.is.one of the ongoing res.arch areas.in as.rophys.cs. s.ar formation is.the fundamental proces. to which our current unders.anding remains.incomplete due to the complexity of the phys.cs.that drives.their formation within molecular clouds. In this.article theoretical modelling of the lowes. pos.ible mas. of the cloud needed for collaps. and the core accretion rate has.been pres.nted for the molecular cloud collaps.ng under its.gravity. In many of previous.s.udies.the critical mas. of s.ar forming cloud under its.gravity has.been modelled us.ng kinetic energy and gravitational potential energy. However, we tes. the effect of thermodynamic efficiency factor together with other phys.cal proces.es.in des.ribing the critical mas., and controlling or triggering the rate of mas. falling onto the central core. As.uming that, the ratio of radiation luminos.ty to gravitational energy releas.d per unit time of the collaps.ng MC is.les. than unity. Following this.conceptual framework we have formulated the critical mas. and the core accretion rate of the s.lf-gravitating molecular cloud.

关键词： s.ar Formation Molecular Cloud Critical Mas. Core Accretion