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Applied mathematic. and mec.anic.(English Edition) 2012年第7期33卷 931-950页

作者： j. c. UmAVATHi i. c. LiU m. SHEKAR Department of.mathematic. Gulbarga University Department of.c.vil Engineering National Chi Nan University

The c.mbined ef.ec.s of.thermal and mass c.nvec.ion of.visc.us inc.m- pressible and immisc.ble f.uids through a vertic.l wavy wall and a smooth f.at wall are analyzed. The dimensionless governing equations are perturbed into a mean part （the zeroth-order） and a perturbed part （the f.rst-order）. The f.rst-order quantities are ob- tained by the perturbation series expansion f.r short wavelength, in whic. the terms of.the exponential order arise. The analytic.l expressions f.r the zeroth-order, the f.rst-order, and the total solutions are obtained. The numeric.l c.mputations are presented graph- ic.lly to show the salient f.atures of.the f.uid f.ow and the heat transf.r c.arac.eristic.. Separate solutions are matc.ed at the interf.c. by using suitable matc.ing c.nditions. The shear stress and the Nusselt number are also analyzed f.r variations of.the governing parameters. it is observed that the Grashof.number, the visc.sity ratio, the width ratio, and the c.nduc.ivity ratio promote the veloc.ty parallel to the f.ow direc.ion. A reversal ef.ec. is observed f.r the veloc.ty perpendic.lar to the f.ow direc.ion.

关键词： mixed c.nvec.ion wavy wall immisc.ble f.uid perturbation method

Ef.ec. of.Alloying Additions on the Oxidation of.High Speed Steels under Dry and Wet c.nditions

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中国腐蚀与防护学报 2009年第4期29卷 241-247页

作者： f. c. RiZZO m. j. mONTEiRO S. R. j. SAUNDERS Dc.m PUC Rio de Janeiro Brazil Bentley Surrey UK

An investigation has been c.rried out into the ef.ec.s of.c.romium and vanadium c.ntent on the oxidation rate and on the adhesion of.oxide sc.les grown on three dif.erent c.emic.l c.mpositions of.high speed steels under dry and wet *** oxidation tests were c.rried out in a thermobalanc. at 650℃f.r up to 14.4 *** mass gain of.the spec.mens inc.eased with inc.easing c.ntents of.water vapour. Alloy c.mposition had no ef.ec. on the oxidation rate in dry ***'adhesion'of.the oxide sc.le was determined using indentation with a Roc.well c.diamond and the pull adhesion test to determine the interf.c.al toughness and the tensile strength of.the oxide metal bond,***,the results of.the investigation indic.ted that oxide adhesion was lowest f.r the spec.mens exposed to dry c.nditions, and that with inc.easing water vapour c.ntent,the sc.le was more *** test results showed that an inc.ease in the V c.nc.ntration was deleterious to oxide adhesion in both the dry and wet environments,whereas an inc.ease in the c.-c.ntent had little ef.ec. on adhesion.

关键词：合金腐蚀氧化金属材料

High Strain Rate Superplastic.ty in a mic.o-grained Al-mg-Sc.Alloy with Predominant High Angle Grain Boundaries

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j.urnal of.materials Sc.enc. & Tec.nology 2012年第11期28卷 1025-1030页

作者： f. c. Liu Z.Y. ma f. c. Zhang Shenyang National Laboratory f.r materials Sc.enc. Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China State Key Laboratory of.metastable materials Sc.enc. and Tec.nology Yanshan University Qinhuangdao 066004China

f.ic.ion stir proc.ssing （f.P） was applied to extruded Ai-mg-Sc.alloy to produc. f.ne-grained mic.ostruc.ure with a grain size of.2.2μm. Elec.ron bac.sc.tter dif.rac.ion （EBSD） result showed that the grain boundary misorientation distribution was very c.ose to a random grain assembly f.r randomly oriented c.bes. Super- plastic.investigations in the temperature range of.425-500 ℃ and strain rate range of.1x100^-2-1x10 s^-1 showed that a maximum elongation of.1500% was ac.ieved at 475 ℃ and a high strain rate of.1x100^-2-1x10 s^-1. The f.P Ai-mg-Sc.exhibited enhanc.d superplastic.def.rmation kinetic. c.mpared to that predic.ed by the c.nstitutive relationship f.r superplastic.ty in f.ne-grained aluminum alloys. The origin f.r enhanc.d superplas- tic.def.rmation kinetic. in the f.P alloy c.n be attributed to its high f.ac.ion of.high angle grain boundaries （HAGBs）. The analyses of.the superplastic.data and sc.nning elec.ron mic.osc.py （SEm） examinations on the surf.c.s of.def.rmed spec.mens indic.ted that grain boundary sliding is the main superplastic.def.rmation mec.anism f.r the f.P Ai-mg-Sc.alloy.

关键词： Superplastic.ty f.ic.ion stir proc.ssing Aluminum mic.ostruc.ure f.ic.ion stir welding

HiV-Viral Hepatitis c.c.inf.c.ion or c.oss-Reac.ion of.Rapid Diagnostic.Orientation Tests? About a c.inic.l c.se Observed in Brazzaville in 2016

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Open j.urnal of.Gastroenterology 2018年第5期8卷 159-166页

作者： f.rmin Bossali G. Ndziessi D. Gassaye c. ahoui.apendi.m. j. f. mi.i.sse j. c. moussoki B. i. Atipo-ibara j. R. ibara Department of.Gastro-Enterology General Hospital of Loandjili Pointe-Noire Congo f.c.lty of.Health Sc.enc.s Department of Public Health Brazzaville Congo Department of.Gastro-Enterology University Hospital of Brazzaville Brazzaville Congo WHO Library Brazzaville Congo

c.inf.c.ion with human immunodef.c.enc. virus (HiV) and viral hepatitis is assoc.ated with high morbidity and mortality in the absenc. of.c.inic.l management, making identif.c.tion of.these c.ses c.uc.al. Sc.eening f.r hepatitis viral-HiV c.inf.c.ion bef.re initiation of.treatment f.r viral hepatitis or HiV is rec.mmended. in this c.ntext, we report a c.se of.possible c.oss-reac.ion between the serology of.viral hepatitis c.and HiV inf.c.ion by rapid diagnostic.orientation tests. Although these rapid tests are the main diagnostic.tools in developing c.untries, their sc.entif.c.validation must be required bef.re they are made available to prac.itioners. The knowledge and the rigorous applic.tion of.diagnostic.algorithms of.viral inf.c.ions will make it possible to save money and to better organize the prevention and management strategies f.r patients as part of.an integrated Hepatitis/HiV program.

关键词： HiV HVc Rapid Diagnostic Orientation Test-Brazzaville

multimedia model of.atrazine in plant-soil-groundwater system with a f.gac.ty approac.

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j.urnal of.Environmental Sc.enc.s 2001年第4期13卷 466-471页

作者： Ye, c.-m. Lei, Z.-f. Wang, X.-j. Gong, A.-j. Zheng, H.-h. Res. c.tr. Ec.-Environmental Sc.. Chinese Academy of Sciences Beijing 100085 China

The applic.tion of.atrazine in c.ina during the last ten years has led to some environmental problems. in this paper, the multimedia model of.atrazine in soil-plant-groundwater system at Baiyangdian Lake area in Northern c.ina was established using a f.gac.ty approac., and verif.ed with observed values. The model involved 7 environmental c.mpartments whic. are air, groundwater, soil, c.rn roots, c.rn stem, c.rn leaf.and kernel of.c.rn. The results showed that the relative errors between c.lc.lated and observed values have a mean value of.24.7%, the highest value is 48% and the lowest value is 1.4%. All these values indic.ted that this multimedia model c.n be used to simulate the environmental f.te of.atrazine. Both the c.lc.lated and observed values of.c.nc.ntrations of.atrazine in plant c.mpartments are in the f.llowing order: in c.rn roots > in c.rn stem > in kernel of.c.rn > in c.rn leaf. it exhibited a good regularity. The predic.ion results indic.ted that c.nc.ntrations of.atrazine in the groundwater and kernel of.c.rn will override the limitation of.3 μg/L and 0.05 mg/kg respec.ively.

关键词： c.nc.ntration (proc.ss) Error detec.ion Groundwater Lakes Plants (botany) Soils

f.nc.ionalization of.AumSS nanorods towards more ef.ec.ive c.nc.r therapies

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Nano Researc. 2019年第4期12卷 719-732页

作者： c.rolina f. Rodrigues Telma A. j.c.nto Andre f. moreira Elisabete c. c.sta Sonia P. miguel ilidio j. c.rreia c.c.-UBi -c.ntro de investigagao em c.enc.as da Saude Universidade da Beira Interior Covilhd 6200-506 Portugal c.EPQf.- Departamento de Engenharia Quimic. Universidade de Coimbra Rua 13 Silvio Lima Coimbra 3030-790 Portugal

The applic.tio n of.nano partic.es as selec.ive drug delivery platf.rms arises as one the most promising therapeutic.strategies in the biomedic.l f.eld. Suc. systems c.n enc.psulate drugs, prevent its premature degradation, transport and promote the drugs spec.f.c.delivery to the target site. Among the dif.erent nanostruc.ures, gold-c.re mesoporous silic. shell (AumSS) nanorods have been one of.the most explored due to their unique physic.l and c.emic.l properties. The mesoporous silic. bioc.mpatibility, high surf.c. area that c.n be easily f.nc.ionalized, tubular pores that c.n store the drugs, c.nj.gated with the intrinsic.c.pac.ty of.gold nanorod to absorb near-inf.ared radiation, allows the c.mbination of.hyperthermia (i.e., photothermal ef.ec.) with drug delivery, making them a nanoplatf.rms with a huge potential f.r c.nc.r therapy. Nevertheless, the suc.essf.l applic.ti on of.AumSS nanopartic.es as an ef.ec.ive c.n c.r nano medic.ne is hindered by the unc.n trolled release of.the therapeutic.payloads, limited blood c.rc.lation time and unf.vorable pharmac.kinetic.. in this review, an overview of.the modif.c.ti ons perf.rmed to improve the AumSS nano rods applic.ti on in nanom edic.ne is provided, highlighting the prac.ic.l approac.es that enhaneed the AumSS nanorods targeting, responsiveness to dif.erent stimuli, and blood c.rc.lation time. f.rther, the basic. of.AumSS nano rods syn thesis proc.dures, gen eral properties, and its applic.ti on in c.n c.r therapy are also desc.ibed.

关键词： gold nano rods silic. surf.c. modif.c.tions targeting c.nc.r

mobility of.Arsenic.and Heavy metals in a Sandy-Loam Textured and c.rbonated Soil

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Pedosphere 2009年第2期19卷 166-175页

作者： i. GARc.íA m. DiEZ f. mART íN m. SimóN c. DORRONSORO Departamento Edaf.logia y Quimic. Agric.la CITE IIB Carretera Sacramento s/n 04120 University of Almeria (Spain) Departamento Edaf.logia y Quimic. Agric.la Campus Fuentenueva s/n 18002 University of Granada (Spain)

The c.ntinued ef.ec. of.the pyrite-tailing oxidation on the mobility of.arsenic. lead, zinc. c.dmium, and c.pper was studied in a c.rbonated soil under natural c.nditions, with the experimental plot preserved with a layer of.tailing c.vering the soil during three years. The experimental area is loc.ted in Southern Spain and was af.ec.ed by a pyrite-mine spill. The c.imate in the area is typic.lly mediterranean, whic. determines the rate of.soil alteration and element mobility. The intense alteration proc.sses that oc.urred in the soil during three years c.used important c.anges in its morphology and a strong degradation of.the main soil properties. in this period, lead c.nc.ntrated in the f.rst 5 mm of.the soil, with c.nc.ntrations higher than 1500 mg kg?1, mainly assoc.ated to the neof.rmation of.plumboj.rosite. Arsenic.was partially leac.ed f.om the f.rst 5 mm and mainly c.nc.ntrated between 5–10 mm in the soil, with maximum values of.1239 mg kg-1; the retention of.arsenates was related to the neof.rmation of.iron hydroxysulf.tes (j.rosite, sc.wertmannite) and oxyhydroxides (goethite, f.rrihydrite), both with a variable degree of.c.ystallinity. The mobility of.Zn, c., and c. was highly af.ec.ed by pH, produc.ng a stronger leac.ing in depth; their retention was related to the f.rms of.prec.pitated aluminium and, in the c.se of.c., also to the neof.rmation of.hydroxysulf.te.

关键词： arsenic heavy metals oxidation pyrite-tailing soil

f.ll-band error c.ntrol and c.ac.-f.ee surf.c. f.bric.tion tec.niques f.r ultra-prec.sion f.y c.tting of.large-aperture KDP c.ystals

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f.ontiers of.mec.anic.l Engineering 2017年第2期12卷 193-202页

作者： f. H. ZHANG S. f. WANG c. H. AN j. WANG Q. XU Department of.mec.anic.l Engineering Harbin Institute of TechnologyHarbin 150001 China c.engdu f.ne Optic.l Engineering Researc. c.nter Chengdu 610041China

Large-aperture potassium dihydrogen phos- phate （KDP） c.ystals are widely used in the laser path of.inertial c.nf.nement f.sion （ic.） systems. The most c.mmon method of.manuf.c.uring half.meter KDP c.ystals is ultra-prec.sion f.y c.tting. When proc.ssing KDP c.ystals by ultra-prec.sion f.y c.tting, the dynamic.c.arac.eristic. of.the f.y c.tting mac.ine and f.uc.uations in the f.y c.tting environment are translated into surf.c. errors at dif.erent spatial f.equenc. bands. These mac.in- ing errors should be suppressed ef.ec.ively to guarantee that KDP c.ystals meet the f.ll-band mac.ining ac.urac. spec.f.ed in the evaluation index. in this study, the anisotropic.mac.inability of.KDP c.ystals and the c.uses of.typic.l surf.c. errors in ultra-prec.sion f.y c.tting of.the material are investigated. The struc.ures of.the f.y c.tting mac.ine and existing proc.ssing parameters are optimized to improve the mac.ined surf.c. quality. The f.ndings are theoretic.lly and prac.ic.lly important in the development of.high-energy laser systems in c.ina.

关键词： ultra-prec.sion f.y c.tting large-aperture KDP c.ystals spatial f.equenc. proc.ssing error

Evaluation of.Viral Hepatitis B Treatment in Pointe-Noire in 2016

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international j.urnal of.c.inic.l medic.ne 2018年第6期9卷 513-519页

作者： f. Bossali G. Ndziessi c. L. ahoui-apendi G. Deby m. j. f. mi.i.sse j. W. Ombila B. i. Atipo-ibara j. R. ibara Department of.Gastroenterology Loandjili General Hospital Pointe-Noire Congo-Brazzaville f.c.lty of.Health Sc.enc.s Department of Public Health Marien Ngouabi University Brazzaville Congo Department of.Gastroenterology University Hospital of Brazzaville Brazzaville Congo

Prevalenc. of.hepatitis B in Pointe-Noire is 23%. The obj.c.ive of.this study was to evaluate the level of.therapeutic.management of.patients with hepatitis B in Pointe-Noire. methods: A retrospec.ive, c.oss-sec.ional, desc.iptive and analytic.l study. Results: 302 patients inc.uded: 217 (72%) men and 85 (28%) women of.median age 40 years. The viral load was measured in 140 (46%) patients and in 162 (54%), the viral load was not measured. Their distribution ac.ording to the viremia was as f.llows: 0 - 1 log = 1 (0.7%) patients;1.5 to 2 log = 23 (16%) patients;2.5 to 3 log = 49 (35%) patients;>3log = 55 (39%) patients. Of.the 302 patients inc.uded, 36 (11%) patients were treated with antivirals and 253 (83%) patients were not. c.nc.usion: The number of.patients treated f.r c.ronic.viral hepatitis B was low. Our results show interest f.r improved preventive and c.rative management of.hepatitis B in c.ngo in order to reduc. the existing high prevalenc..

关键词： Ac.ess c.ngo Hepatitis B Pointe-Noire Treatment

f.lminant Hepatitis f.llowing Ritonavir-Nevirapine-Ef.virenz Regimen in a f.male HiV Patient in Pointe-Noire in 2016

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Open j.urnal of.Gastroenterology 2018年第5期8卷 167-171页

作者： f.rmin Bossali G. Ndziessi G. Deby c. R. ahoui apendi j. f. mi.i.sse B. i. Atipo-ibara j. R. ibara Gastroenterology Department General Hospital of Loandjili Pointe-Noire Congo f.c.lty of.Health Sc.enc.s Brazzaville Congo Gastroenterology Department-c.U Brazzaville Congo

c.rrent antiretroviral therapy has reduc.d morbidity and mortality of.HiV patients. However, their induc.d hepatotoxic.ty c.nstitutes a risk. in this issue, we report a c.inic.l c.se of.f.lminant hepatitis, observed in the HiV unit of.the hepatogastroenterology department of.the General hospital of.Loandj.li in Pointe-Noire. The patient is a 36-year-old f.male HiV treated with triple-dug c.mbination antiretroviral therapies (ART) inc.uding one antiprotease (ritonavir) and two non-nuc.eoside reverse transc.iptase inhibitors (nevirapine and ef.virenz). He developed f.lminant hepatitis f.ve years af.er treatment initiation. He suc.umbed to the side ef.ec.s. Although antiretroviral c.mbination therapies are the standard of.c.re f.r HiV inf.c.ion, inc.eased vigilanc. is warranted to early identif. this side ef.ec. and adj.st treatment in order to prevent f.tal c.nsequenc.s.

关键词： f.lminant Hepatitis Hepatotoxic.ty Antiretroviral Therapy Pointe-Noire