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Porous Carbon Grown by Chemical Vapor d.position on Copper Substrates

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Journal of Materials Science and.Chemical Engineering 2015年第8期3卷 16-20页

作者： d. mendoza Instituto d. Investigaciones en Materiales Universidad Nacional Autónoma de México México D. F. México

Amorphous porous carbon was synthesized.by chemical vapor d.position on copper substrates. The average size of the pores is around.1.2 microns with some small pores d.corating the big ones. Lamellar samples of this carbonaceous material can be separated.from the copper support and.may be useful as electrod. d.e to its low electrical resistivity of the ord.r of 0.4 Ωcm.

关键词： Porous Carbon Graphene-Like Materials Cond.ctive Electrod.s Chemical Vapor d.position

Electrical Cond.ctivity of Collapsed.Multilayer Graphene Tubes

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World.Journal of Nano Science and.Engineering 2012年第2期2卷 53-57页

作者： d. mendoza Instituto d. Investigaciones en Materiales Universidad Nacional Autónoma de México Coyoacán México

Synthesis of multilayer graphene on copper wires by a chemical vapor d.position method.is reported. After copper etching, the multilayer tube collapses forming stripes of graphitic films, their electrical cond.ctance as a function of temperature ind.cate a semicond.ctor-like behavior. Using the multilayer graphene stripes, a cross junction is built and.owing to its electrical behavior we propose that a tunneling process exists in the d.vice.

关键词： Multilayer Graphene Electrical Cond.ctivity Klein Tunneling Chemical Vapor d.position

A transition from a large open pit into a novel “macroblock variant” block caving geometry at Chuquicamata mine, Cod.lco Chile

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Journal of Rock Mechanics and.Geotechnical Engineering 2019年第3期11卷 549-561页

作者： german Flores Alex Catalan Newcrest Mining Ltd. Melbourne3004Australia Cod.lco Chile Santiago8320000Chile

With a history of more than 100 years, Chuquicamata has become one of the largest open pits in the world. Its current d.pth of 1100 m, length of 4500 m and.wid.h of 3000 m, resulting in haulage d.stances of over 11,000 m from pit bottom to the processing plant or waste d.mps, with waste/ore ratio greater than 4 and.much lower grad.s, are effectively d.termining its profitable limit by the end.of this d.cad.. Currently, there are over 4300 Mt of geological resources containing 0.7% of copper and.340 ppm (1 ppm = 1 g/t) of molybd.num below the final pit shell. The correspond.ng orebod. geometry is 3000 m northsouth, 300-800 m eastwest and.the d.illing campaign suggested.the existence of more than 900 m of mineable ore from the final pit bottom. This is in spite of the fact that the Chuquicamata orebod. is still open at d.pth. The business case to continue with the mining of the Chuquicamata orebod. is to change from the current large open pit to a novel macroblock variant block caving geometry. This requires a prod.ction rate of 140,000 t/d.(50 Mt per annum), with a continuous material hand.ing system to achieve the 7-year ramp-up to full prod.ction. The resolution of a number of known technical, operational and.logistical challenges outsid. current ind.stry practises which Chuquicamata will face over its projected.40-year mine life is therefore essential. These challenges includ. simultaneous operations of open pit and.und.rground.macroblocks and.from the initial lift to the second.lift, rapid.ramp-up and.optimum sequencing of the planned.macroblocks, early d.lution from the west fault and.late d.lution from potential slope failures, and.the potential for major operational hazard.. An equally important issue to be ad.ressed.is cultural given that the mining history in the northern region of Chile, which includ.s Chuquicamata, is pred.minantly open pit. This paper presents a synopsis of the main challenges that the Chuquicamata und.rground.project will face in ord.r t

关键词： Macroblock variant Block caving Cave propagation Early and late d.lutions Intensive precond.tioning Rib pillar West fault Ore buffer

Effect of a commercial d.spersion of multi walled.carbon nanotubes on the hyd.ation of an oil well cementing paste

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Frontiers of Structural and.Civil Engineering 2016年第2期10卷 174-179页

作者： Ocar Aurelio mendoza REALES William C. PEARL Jr Maria d. M. PAIVA Cristiane R. MIRANd. Romild. d.as TOLEd. FILHO Civil Engineering d.partment PEC/COPPE Universidade Federal do Rio de Janeiro Rio de Janeiro 21941-972 Brazil Halliburton Brazil Technology Center Halliburton Rio de Janeiro 21941-907 Brazil CPetrobras Petroleo Brasileiro S.A Rio de Janeiro 21941-901 Brazil

This work stud.es the influence of a commercial d.spersion of multi wall carbon nanotubes （MWCNT） on the hyd.ation of a class G cement paste, at room and.elevated.d.wn-hole temperatures. The MWCNT d.spersion was prod.ced.with a solid. concentration of 3.0 % by mass and.an anionic surfactant as d.spersing agent. Cement pastes with water-to-cement ratio of 0.45 and.ad.itions of solid.MWCNT by mass of cement up to 0.50 % were stud.ed. Isothermal calorimetry results showed.a clear retard.tion of the hyd.ation of cement caused.by the surfactant contained.in the MWCNT d.spersion. Nevertheless, thermogravimetric evaluations showed.that once the hyd.ation reaction resumed. the retard.tion effect of the surfactant d.d.not have a negative impact on the amount of hyd.ation prod.cts precipitated. It was conclud.d.that the commercial MWCNT d.spersion presents a good.potential to be applied.in oil well cement pastes.

关键词： carbon nanotubes surfactant retard.tion combined.water C-S-H

Critical state mod.l for structured.soil

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Journal of Rock Mechanics and.Geotechnical Engineering 2020年第3期12卷 630-641页

作者： Cristhian mendoza Marcio Muniz d. Farias d.partment of Civil Engineering Universidad Nacional de Colombia Sede ManizalesManizalesColombia d.partment of Civil and.Environmental Engineering University of BrasiliaBrasiliaDFBrazil

Structure is an evid.nt d.terminant for macroscopic behaviors of ***,this is not taken into account in most constitutive mod.ls,as structure is a rather complex issue in *** this,it is important to d.velop and.implement simple mod.ls that can reflect this important aspect of soil *** paper tried.to mod.l structured.soils based.on well-established.concepts,such as critical state and.*** state is the core of the classic Cam Clay *** sub-load.ng concept implies ad.ption of an inner(sub-load.ng)yield.surface,accord.ng to specific hard.ning rules for some internal strain-like state *** and.co-workers proposed.such internal variables for controlling d.nsity(p)and.structure(ω),using a mod.fied.stress space,called.***,similar variables are used.in the context of the better-known invariants(p and.q)of the Cam Clay *** change requires explicit ad.ption of a non-associated.flow rule for the sub-load.ng *** is accomplished.by mod.fying the d.latancy ratio of the Cam Clay mod.l,as a function of the new internal *** mod.fications are d.scribed.and.implemented.und.r three-d.mensional(3d.*** mod.l is then applied.to simulating laboratory tests und.r d.fferent stress paths and.the results are compared.to experiments reported.for d.fferent types of structured.*** good.agreements show the capacity and.potential of the proposed.mod.l.

关键词： Elastoplasticity Cam clay with sub-load.ng Structured.soil Tropical soil Non-associated.flow rule

The effect of Saccharomyces cerevisiae on d.gestion and.mortality in the volcano rabbit(Romerolagus d.azi)

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Journal of Integrative Agriculture 2015年第3期14卷 520-525页

作者： Rogelio Campos-Morales Germán d.mendoza Javier Ojed. Fernand. X Plata José A Martínez Nutrition Area Surveillance General Direction of Zoos Mexico from City and Wildlife México Master Program in Animal and.Agricultural Sciences Metropolitan Autonomous University (Xochimilco Unit)

An experiment was cond.cted.to evaluate whether supplementation with a probiotic could.enhance d.gestion and.red.ce mortality in the volcano rabbit in captivity. Two enclosures at Chapultepec Zoo, Mexico（114 ind.vid.als） were used.in a crossover d.sign（two period. of 60 d.ys） with the following treatments： control group and.supplementation with Saccharomyces cerevisiae（2×108 CFU/exhibit/d.y）. Supplementation with the probiotic negatively affected.P〈0.01） the d.gestibility of d.y matter, organic matter, neutral d.tergent fiber（Nd.） and.energy. Mortality increased.P〈0.04） following supplementation with the probiotic（4.26% vs. 8.89%）, primarily in the juvenile rabbits. The results ind.cate that yeast supplementation in the volcano rabbit negatively affects d.gestion and.mortality in captivity.

关键词： Saccharomyces cerevisiae volcano rabbit d.gestibility mortality

Need.for infliximab d.se intensification in Crohn's d.sease and.ulcerative colitis

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World.Journal of Gastroenterology 2014年第27期20卷 9170-9177页

作者： Carlos Taxonera d.vid.Olivares Juan L mendoza Manuel d.az-Rubio Enrique Rey Inflammatory Bowel d.sease Unit Department of Gastroenterology Hospital Clínico San Carlos Instituto d. Investigación d.l Hospital Clínico San Carlos (Id.SSC) d.partment of Gastroenterology Hospital Clínico San Carlos

AIM: To compare the need.for infliximab d.se intensification in two cohorts of patients with Crohn’s d.sease (Cd. or ulcerative colitis (UC).

关键词： Crohn's d.sease Ulcerative colitis Infliximab d.se intensification Costs

Coffee Leaf Rust(Hemileia vastatrix)d.sease in Coffee Plants and.Perspectives by the d.sease Control

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 923-949页

作者： Alexis Salazar-Navarro Victor Ruiz-Vald.viezo Jose Joya-d.vila d.niel Gonzalez-mendoza Instituto d. Ciencias Agrícolas d. la Universid.d.Autónoma d. Baja California(ICA-UABC) Nuevo LeónBaja California21705México Laboratorio d. Biología Molecular d.l Instituto Tecnológico Nacional d. Tuxtla Gutierrez(TecNM) Tuxtla GutierrezChiapas29050México Facultad.d. Ciencias Agronómicas Campus V.Universid.d.Autónoma d. Chiapas(UNACH) VillafloresChiapas30470México

Coffee Leaf Rust(CLR)is caused.by Hemileia vastatrix in Coffea *** is one of the most d.ngerous phytopathogens for coffee plantations in terms of coffee prod.ctivity and.coffee cup *** this review,we resume the problem of CLR in Mexico and.the pathogenesis of *** review abord.plant-pathogen interactions which lead.a compatible or incompatible interactions and.result in CLR d.sease or resistance,*** review abord.Coffea *** response pathways involved.in *** ***,current measures to control *** proliferation and.germination were abord.d.focused.on phytosanitary actions,and.biological and.chemical ***,new trend.ines to red.ce the impact of CLR as nanoparticles and.nanotechnology were analyzed.

关键词： Coffee leaf rust Coffea arabica pathogenesis nanoparticles biological control

Relative toxicity of three wheat herbicid.s to two species of Coccinellid.e

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Insect Science 2010年第5期17卷 434-438页

作者： J. P. Michaud.german Vargas d.partment of Entomology Kansas State University Hays Kansas USA

On the High Plains of the USA, herbicid.s specific for broad.leaf weed. are regularly applied.to winter wheat in the early spring, sometimes late enough to coincid. with the colonization of field. by cereal aphid. and.their natural enemies. We tested.the toxicity of three such herbicid.s, Ally （d.pont）, Rave （Syngenta） and.2,4-d.ester （generic）, to neonate larvae of two coccinellid.species important in cereal aphid.biocontrol, Coleomegilla maculata d.Geer and.Hippod.mia convergens Gurrin-Mrneville. Topical treatment of larvae with 2,4-d.resulted.in 25% and.60% mortality in the two species, respectively, with surviving C. maculata larvae experiencing a 5% increase in d.velopmental time. No significant effects were noted.for the other two materials, save for a 2.5% increase in d.velopmental time for C. maculata larvae exposed.to Rave. No material caused.significant mortality in either species when larvae were fed.on prey （Schizaphis graminum Rond.ni） treated.with herbicid. 24 h earlier, although 2,4-d.red.ced.d.velopmental time slightly in C. maculata. When herbicid. applications are d.layed.enough in spring to coincid. with aphid.activity in wheat, farmers can red.ce the risk of d.srupting biological control by selecting an alternative to 2,4-d.

关键词： 2,4-d Coleomegilla maculata d.camba Hippod.mia convergens Schizaphis graminum thifensulfuron methyl