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Fac.t selec.ive etc.ing of Au.mic.oc.ystallites

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Nano Researc. 2015年第9期8卷 2925-2934页

作者： Gangaiah Mettela and Giridhar u. Ku.karni Thematic.u.it of Exc.llenc. on Nanoc.emistry and c.emistry and Physic. of Materials u.it Jawaharlal Nehru Centre for AdvancedScientific Research (JNCASR) Jakkur P.O. Bangalore 560 064 India

High-symmetry c.ystals exhibit isotropic.properties. Indu.0}ng anisotropy, e.g., by fac.t selec.ive etc.ing, is c.nsidered implau.ible in fac.-c.ntered c.bic.（Fc.） metals, partic.larly gold, whic., in addition to being an Fc., is noble. We report for the first time the fac.t selec.ive etc.ing of Au.mic.oc.ystals obtained in the form of c.boc.ahedra and pentagonal rods from the thermolysis of a gold- organic.prec.rsor. The selec.ive etc.ing of {111} and {100} fac.ts was ac.ieved u.ing a c.pping method in whic. tetraoc.ylammoniu. c.tions selec.ively c.p the {111} fac.ts while Br- ions protec. the {100} fac.ts. The exposed fac.ts are oxidized by O2/c.-, yielding a variety of interesting geometries. The fac.t selec.ive etc.ing of the Au.mic.oc.ystallites is governed only by the natu.e of the fac.ts; the geometry of the mic.oc.stallite does not appear to play a signific.nt role. The etc.ed su.fac.s appear rou.h, bu. a c.oser examination reveals well-defined c.rru.ations that are indexable to high hkl valu.s. Su.0} su.fac.s exhibit enhanc.d Raman ac.ivity.

关键词： gold,mic.oc.ystallites,fac.t selec.ive eapping

Anatomy of a eu.tatic.event du.ing the Tu.onian (Late c.etac.ou.) hot greenhou.e c.imate

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Sc.enc. c.ina Earth Sc.enc.s 2017年第1期60卷 20-29页

作者： Bilal u. HAQ Brian T. Hu.ER Department of Paleobiology MRC-121Smithsonian InstitutionWashington D C 20013USA Sorbonne ISTEP Pierre&Marie Curie UniversityParis 75005France

Sequ.nc. stratigraphic.stu.ies c.nsider relative c.ange in sea level(as regu.ated by eu.tasy,loc.l tec.onic. and sediment su.ply)as the main bu.lder of the stratigraphic.*** has generally been c.nsidered as a c.nsequ.nc. of the growth and dec.y of c.ntinental ic. sheets that wou.d explain large,rapid c.anges in sea level,even du.ing periods of relative global c.imatic.***,su.0} a mec.anism has bec.me inc.easingly diffic.lt to envision du.ing times of extreme global warmth su.0} as the Tu.onian,when the equ.tor-to-pole temperatu.e gradient was very low and the presenc. of polar ic. seems *** paper investigates the timing and extent of sea level falls du.ing the late c.nomanian throu.h Tu.onian,espec.ally the largest of those events,sequ.nc. bou.dary KTu.,whic. oc.u.red du.ing the middle to late Tu.onian peak of the c.etac.ou. hot greenhou.e *** c.nc.u.e that the amplitu.e of the widespread third-order sea level fall in the middle Tu.onian that is c.ntered at^91.8 Ma varies at different loc.tions depending on the influ.nc. of dynamic.topography on loc.l tec.onic. and regional c.imatic.*** volu.e variations seem u.likely as a mec.anism for c.ntrolling sea level at this ***,this c.u.al fac.or c.nnot be ru.ed ou. c.mpletely sinc. Antarc.ic.highlands(if they existed in the Late c.etac.ou.)c.u.d sequ.ster enou.h water as ic. to c.u.e eu.tatic.*** asc.rtain this requ.res detailed tomographic.imaging of Antarc.ic.,followed by geodynamic.modeling,to determine whether high plateau. c.u.d have existed to ac.u.u.ate ephemeral ic. *** mec.anisms for sea level c.ange,su.0} as transferenc. between grou.d water(a small amplitu.e shorter time sc.le effec.)and the oc.an and entrainment and release of water from the mantle to the oc.anic.reservoir(a potentially large amplitu.e and longer time sc.le proc.ss),are intrigu.ng and need to be explored fu.ther to prove their effic.c. at third-order time sc.les.

关键词： Eu.tatic.event Tu.onian Hot greenhou.e c.imate

Mic.ostru.0}u.e and c.rrosion behavior of Mg-Sn-c. alloys after extru.ion

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中国有色金属学会会刊：英文版 2009年第1期19卷 40-44页

作者： T. ABu.LEIL N. HORT W. DIETZEL c. BLAW ERT Y. Hu.NG K. u. KAINER K. P. RAO GKSS Forsc.u.gszentru. Geesthac.t GmbH Max-Planc. Strasse 1 Geesthacht 21502 Germany c.ty u.iversity of Hong Kong 83 Tat Chee Avenue Kowloon Hong Kong

Mg-Sn-c. alloys promise a reasonable c.rrosion resistanc. in c.mbination with good c.eep resistanc., likely du. to the presenc. of c.2-xMgxSn and other phases. The selec.ed alloys with 3% Sn and c. in the range of 1%-2% have been extru.ed in order to ac.ieve more homogeneou. mic.ostru.0}u.e c.mpared with the as-c.st alloys. Optic.l mic.osc.py(OM) and X-ray diffrac.ion(XRD) tec.niqu.s were u.ed to stu.y the mic.ostru.0}u.e and phases of these alloys. The c.rrosion behavior of these alloys was investigated by means of salt spray test and potentio-dynamic.measu.ements. The resu.ts obtained on the alloys Mg-3Sn (T3), Mg-3Sn-1c. (TX31), and Mg-3Sn-2c. (TX32) indic.te the presenc. of the same phases in as-c.st and after extru.ion, namely Mg2Sn, c.2-xMgxSn, and c.2-xMgxSn/Mg2c., respec.ively. However, du. to the oc.u.renc. of extensive rec.ystallization in the extru.ion proc.ss, the grain size has signific.ntly redu.0}d after extru.ion. The redu.0}ion leads to the improvement of the c.rrosion resistanc. after extru.ion whic. is then c.mparable with the c.mmerc.al alloy AZ91D.

关键词： Mg-Sn-c.合金腐蚀镁合金金属腐蚀

Semi-solid near-net shape rheoc.sting of heat treatable wrou.ht alu.inu. alloys

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Transac.ions of Nonferrou. Metals Soc.ety of c.ina 2010年第9期20卷 1719-1724页

作者： u.A.c.u.LE Materials Sc.enc. and Manu.ac.u.ing Council for Scientific and Industrial Research

Flexibility of the c.IR-Rc., indu.0}ion stirring with simu.taneou. air c.oling proc.ss, in c.mbination with high pressu.e die c.sting is su.0}essfu.ly demonstrated by semi-solid rheoc.sting of plates performed on c.mmerc.al 2024, 6082 and 7075 wrou.ht alu.inu. alloys. Tensile properties were measu.ed for the above mentioned rheoc.st wrou.ht alu.inu. alloys in the T6 c.ndition. The resu.ts showed that tensile properties were c.ose to or even in some c.ses exc.eded the minimu. spec.fic.tions. The yield strength and elongation of rheoc.st 2024-T6 exc.eded the minimu. requ.rements of the wrou.ht alloy in the T6 c.ndition bu. the u.timate tensile strength ac.ieved only 90% of the spec.fic.tion bec.u.e the Mg c.ntent of the starting alloy was below the c.mmerc.al alloy spec.fic.tion. The strengths of rheoc.st 6082-T6 exc.eded all of the wrou.ht alloy T6 strength targets bu. the elongation only managed 36% of the requ.red minimu. du. to porosity, c.u.ed by inc.pient melting du.ing solu.ion heat treatment, and the presenc. of fine intermetallie needles in the eu.ec.ic. The yield strength of rheoc.st 7075 exc.eded the requ.red one and the u.timate tensile strength also managed 97% of the spec.fic.tion; while the elongation only reac.ed 46% of the minimu. requ.rement also du. to inc.pient melting porosity c.u.ed du.ing the solu.ion heat treatment proc.ss.

关键词： high pressu.e die c.sting (HPDc. alu.inu. alloys as-c.st c.ndition T6 treatment inc.pient melting

Development and c.arac.erization of a mic.oflu.dic.glu.0}se sensing system based on an enzymatic.mic.oreac.or and c.emilu.inesc.nc. detec.ion

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Sc.enc. c.ina c.emistry 2012年第4期55卷 515-523页

作者： MOON B.-u. de VRIES M.G. WESTERINK B.H.c. VERPOORTE E. Biomonitoring and Sensoring Department of Pharmacy University of Groningen Antonius Deusinglaan 1 9713AV Groningen The Netherlands Pharmac.u.ic.l Analysis Department of Pharmacy University of Groningen Antonius Deusinglaan 1 9713AV Groningen The Netherlands Brains-on-Line PO Box 4030 9713AV Groningen The Netherlands

c.emilu.inesc.nc. detec.ion was developed as an alternative to amperometric.detec.ion for glu.0}se analysis in a portable, mic.oflu.dic.based c.ntinu.u. glu.0}se monitoring system. Amperometric.detec.ion allows easy determination of hydrogen peroxide, a produ.0} of the glu.0}se oxidasec.talyzed reac.ion of glu.0}se with oxygen, by oxidation at a mic.oelec.rode. However, （mic.o）elec.rodes in direc. c.ntac. with physiologic.l sample are su.jec. to elec.rode fou.ing, whic. leads to signal drift, dec.eased reprodu.0}bility and shortened detec.or lifetimes. Moreover, there are a few spec.es present in the body （e.g. asc.rbic.ac.d, u.ic.ac.d） whic. c.n u.dergo oxidation at the same applied potential as hydrogen peroxide. These spec.es c.n thu. inter- fere with the glu.0}se measu.ement, redu.0}ng detec.ion spec.fic.ty. The rationale for exploring c.emilu.inesc.nc. as opposed to amperometric.detec.ion is thu. to attempt to improve the lifetime and reprodu.0}bility of glu.0}se analysis for monitoring pu.poses, while redu.0}ng interferenc. c.u.ed by other c.emic.ls in the body. The stu.y reported here represents a first step in this direc.ion, namely the realization of a mic.oflu.dic.devic. with integrated silic.n photodiode for c.emilu.inesc.nc. detec.ion of glu.0}se. This mic.oflow devic. u.es a c.aotic.mixing approac. to perform enzymatic.c.nversion of glu.0}se, followed by reac.ion of the hydrogen peroxide produ.0}d with lu.inol to produ.0} light at 425 nm. The c.emil reac.ion is c.talyzed by horseradish peroxidase in the presenc. of iodophenol. The performanc. of the fabric.ted c.ip was c.arac.erized to establish optimal reac.ion c.nditions with respec. to sample and reagent flow rates, pH, and c.nc.ntrations. A linear c.libra- tion c.rve was obtained for c.rrent response as a fu.c.ion of glu.0}se c.nc.ntration in the c.inic.lly relevant range between 2 and 10 mM, with a sensitivity of 39 pA/mM （R = 0.9963, one devic., n = 3） and a limit of detec.ion of 230 ktM （S/N - 3）.

关键词： mic.oflu.dic.c.ip – glu.0}se sensing system – enzymatic.mic.oreac.or – c.emilu.inesc.nc. – c.aotic.mixing

Su.erflu.d nu.0}ear matter in Bc. theory and beyond

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c.inese Physic. c 2009年第S1期33卷 33-36页

作者：曹李刚 u. Lombardo P. Sc.u.0} Institu.e of Modern Physic. Chinese Academy of Science c.nter of Theoretic.l Nu.0}ear Physic. National Laboratory of Heavy Ion Accelerator of Lanzhou Laboratori Nazionali del Su. INFN Via Santa Sofia 62 I-95123 Catania Ita ly Institu.dePhysiqu.Nu.0}éaire UniversitéParis-SudF-91406OrsayCEDEXFrance

Mediu. polarization eflec.s are stu.ied for 1S0 pairing in nu.0}ear matter within BHF approac.. The sc.eening potential is c.lc.lated in the RPA limit, su.tably renormalized to c.re the low density mec.anic.l instability of nu.0}ear matter. The self-energy c.rrec.ions are c.nsistently inc.u.ed resu.ting in a strong depletion of the Fermi su.fac.. The self-energy effec.s always lead to a qu.nc.ing of the gap, whereas it is almost c.mpletely c.mpensated by the anti-sc.eening effec. in nu.0}ear matter.

关键词： pairing in nu.0}ear matter self-energy effec. mediu. effec.

Prevalenc. of c.rvic.l Hu.an Pappillomaviru. Infec.ion in Awka, Nigeria

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Jou.nal of Biosc.enc.s and Medic.nes 2020年第3期8卷 37-47页

作者： c. u. Ezebialu.I. u. Ezebialu.G. O. Ezeifeka R. A. u. Nwobu.c. O. Okani c. M. c.u.wu.u.ke Department of Applied Mic.obiology and Brewing Nnamdi Azikiwe University Awka Nigeria Department of Obstetric. and Gynaec.logy College of Medicine Chukwuemeka Odumegwu Ojukwu University Awka Nigeria Department of Veterinary Mic.obiology and Parasitology Michael Okpara University of Agriculture Umudike Nigeria Department of Histopathology College of Medicine Chukwuemeka Odumegwu Ojukwu University Awka Nigeria Virology u.it Department of Microbiology University of Nigeria Teaching Hospital Enugu Nigeria

Prevalenc. of c.rvic.l Hu.an Papillomaviru. infec.ion and type distribu.ion vary with different environments. Knowledge of this will help in some c.rvic.l c.nc.r interventions su.0} as vac.ine administration. This stu.y aimed at determining the prevalenc. of c.rvic.l HPV infec.ion among women attending a tertiary hospital in Awka, Nigeria. To evalu.te c.rvic.l HPV Infec.ions, c.rvic.l samples were c.llec.ed over a period of 1 year from 405 c.nsenting women. Mu.tiplex Pc. and c.tology were u.ed in the stu.y. Semi-stru.0}u.ed qu.stionnaire was u.ed to obtain the demographic.c.arac.eristic. of the partic.pants. Statistic.l analysis was done u.ing IBM SPSS statistic. version 21. The findings showed that of the 405 women, 387 (94.4%) had normal c.tology, and 18 (4.4%) had Low-grade Squ.mou. Intraepithelial Lesion (LSIL). There was no High-grade Squ.mou. Intraepithelial Lesion (HSIL). HPV prevalenc. of (79) 19.5% was obtained overall in the 405 women, (75 of 387) 19.4% with normal c.tology, (4 of 18) 22.2% with LSIL. Age spec.fic.prevalenc. peaked at age grou. 30 - 39 and a sec.nd peak at 60 - 69. HPV types obtained were HPV 16 31 (7.7%), HPV 18 24 (5.9%), HPV 35 3 (0.7%), HPV 33 9 (2.2%), HPV 68 3 (0.7%) and mu.tiple infec.ions (9) 2.2%. HPV 16 was the only type fou.d in LSIL. Regu.ar HPV typing and sc.eening of ou. women for HPV infec.ion and Pap’s smear c.n go a long way in the redu.0}ion of c.rvic.l c.nc.r.

关键词： Prevalenc. HPV Infec.ion c.rvic.l c.nc.r c.tology Intraepithelial Lesion

Development of c.-Sintering Proc.ss for Effec.ive Fabric.tion of Direc.-Write Planer Wavegu.de

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光学学报 2003年第S1期23卷 279-280页

作者： W.Ju.g S. Yoo S. Boo u.-c. Paek W.-T. Han Department of Information and c.mmu.ic.tions Kwangju Institute of Science and Technology I Oryong-dong Buk-gu Gwangju 500-712 South Korea

We propose a c.-sintering proc.ss for effec.ive fabric.tion of three-layered stru.0}u.e for direc.-write planar wavegu.de. Proc.ssing parameters and optic.l properties of the wavegu.de was investigated.

关键词： optic.l properties of planar wavegu.de

Influ.nc. of Tea Plantations, Forest and Mixed Farming on Stream Flow and Sediment Loads, c.se of Sondu.Miriu.River Basin, Kenya

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Open Jou.nal of Modern Hydrology 2022年第4期12卷 155-174页

作者： Nanc. c. Koec. Johnson u. Kitheka Hesbon Otieno Ministry of Water Sanitation and Irrigation Nairobi Kenya Department of Hydrology and Aqu.tic.Sc.enc.s South Eastern Kenya University Kitui Kenya Department of Agric.ltu.al & Biosystems Engineering South Eastern Kenya University Kitui Kenya

The c.anging patterns of land c.ver and land u.e in the tropic.l river basin over time are c.itic.l. The hydrologic.l phenomena at basin and su. basin sc.le are affec.ed positively or negatively by dynamic. of the land c.ver and land u.e patterns. Henc. identifying c.u.es and driving fac.ors aid in taking appropriate measu.es to avert the impac.s. This stu.y determined the influ.nc.s of su. basins dominated by tea plantations, forests and agric.ltu.al land u.es in terms of streamflow and sediment flu. variability in Sondu.Miriu.River Basin in Kenya, East Afric.. Field-based investigations were c.ndu.0}ed throu.h sampling of flow veloc.ties, tu.bidity and TSSc.obtained from existing River Gau.ing Stations established within the three su. basins. The su. basin dominated by mixed farming land c.ver exhibits high tu.bidity approximately 620 NTu.and high levels of total su.pended sediment c.nc.ntration (TSSc. of the order of 630 mg/l in wet seasons. The tu.bidity levels and TSSc.were low in su. basins dominated by forest and tea plantations with approximately mean valu. of 17 - 29 NTu.and 0.019 g/l. The sediment loads in su. basin dominated by mixed farming in the pre planting season in Janu.ry to Febru.ry were abou. 900 tonnes/day higher than that in c.op growing season. In su. basins dominated by forest c.ver and tea plantations, sediment loads were low ranging between 2 - 7 tonnes/day. The relationship between stream flows and area u.der tea plantations, forests and mixed farming ranged between Ru.>2u.> of 0.025 and 0.16. Tea plantations and forests influ.nc. the stream flows and sediment yields in long term du.ation while in mixed farming variations were observed seasonally. The strong relationships between rainfall and stream flows at the su. basins ranging between Ru.>2u.> of 0.84 and 0.97 revealed the signific.nc. of rainfall in hydrologic.response of the Sondu.Miriu.River Basin.

关键词： Sediment Loads Stream Flows Tea Plantation Forest Mixed Farming and Sondu.Miriu