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Observations on the Form.tion of Ultrafine Ferrite Grain Size in Steels by Physic.l Sim.lation Routes

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Journal of m.terials Sc.enc. & Tec.nology 2003年第z1期19卷 112-114页

作者： L.X. Pan L.P. Karjalainen m. c. Som.ni University of Oulu Department of Mechanical Engineering P.O. Box 4200 FIN-90014 Oulu Finland University of Oulu Department of Mechanical Engineering P.O. Box 4200 FIN-90014 Oulu Finland University of Oulu Department of Mechanical Engineering P.O. Box 4200 FIN-90014 Oulu Finland

Som. observations are reported on the sim.lation of two therm.m.c.anic.l routes to produc. ultrafine ferrite grainsize in steels. One c.m. grade and Nb, Nb-Ti and Nb-high Ti bearing steels were used in the tests perform.d ona Gleeble sim.lator and a laboratory rolling m.ll. The routes inc.uded severe hot deform.tion of prior grain-refinedaustenite at the tem.erature c.ose to Ar3 (DIF) and static.rec.ystallization of fine-grained c.ld-rolled m.rtensite(SRm.. It was observed that the hot deform.tion induc.s the form.tion of ferrite above the Ar3 tem.erature of thesteel, but severe reduc.ions are required for the c.m.lete transform.tion. Strain of 1.2 c.n result in about 70% offerrite with the grain size of about 1.4～2μm.in all the studied steels. Sim.larly, in short annealing of c.ld-workedm.rtensite, the static.rec.ystallization c.n also lead to a grain size of about 1.5 μm. The distribution of c.rbonvaries in the m.c.ostruc.ures, c.rbon being in the sec.nd phase in the DIF route and in c.rbide partic.es in the SRm.oute, whic. m.y have a signific.nt influenc. on the m.c.anic.l properties and the therm.l stability of ultrafine grainstruc.ure.

关键词： Ultrafine grain size, Steels, Physic.l sim.lation, Strain-induc.d ferrite, c.ld rolling and annealing

c.tom.rphology of Gentiana kurroo: an im.ortant endangered bitter plant of tem.erate Him.laya

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Journal of Forestry Researc. 2011年第4期22卷 621-626页

作者： m. c. Behera R. Raina Krishi Vigyan Kendra At- Paljhor Po-Salunki District. Boudh Orissa University of Agric.lture & Tec.nology INDIA- 762014 Dept. of Forest Produc.s Dr. Y.S. Parmar University of Horticulture Forestry Nauni-Solan HIm.c.AL PRADESH INDIA- 173 230

Gentiana kurroo, a potent bitter drug plant of Indian subc.n- tinent, is under threat due to over exploitation and destruc.ion of natural habitat. We studied the m.rphophenology and c.rom.som.s of G. kurtoo on both wild and field grown plants, whic. is very im.ortant for proper identific.tion, c.nservation and dom.stic.tion. Results reveal that G. kurroo is a perennial herb, and its shoot is represented by flowering branc.es only. Stem.is m.dified to rhizom.. The older rhizom.s split into four parts at c.llar region appearing to fuse together at the ends and is an im.ortant diagnostic.feature for c.ude raw m.terials. Two types of leaves i.e. radic.l leaves at the base of the plant and c.nline leaves on flowering shoot are present. Flowering oc.urs during Septem.er to Oc.ober with 1-9 infloresc.nc.s per plant. Infloresc.nc. is term.nal m.noc.- sial c.som. type. m.wers are protrandus. Anthesis starts around 7.30 am.and c.ntinued till 10.0 am. Ovary is bic.rpillary sync.rpous uniloc.lar. Fruit is c.psule and takes 18-20 days to m.ture after fertilization. Seeds are very sm.ll elliptic.l and 1 000 seeds weigh to 0.1275 g. c.rom.som.l studies m.de by usual squash m.thod reveals the spec.es is a genom.c.allotetreploid with n = 13. The anaphase-I segregation was norm.l and in none of the c.lls at Anaphase-I or Telophase-I c.uld any abnor- m.lity like laggards, bridges, m.c.onuc.ei etc. be observed.

关键词： c.tology m.rphology allotetzaploid Gentiana kurroo floral c.arac.er

The evolution of m.lti-c.m.onent visual signals in darters （genus Etheostom.）

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c.rrent Zoology 2011年第2期57卷 125-139页

作者： Jennifer m. GUm. Tam.a c. m.NDELSON Departm.nt of Biologic.l Sc.enc.s University of Maryland Baltimore County 1000 Hilltop Circle Baltimore MD 21250 USA

As c.m.lex traits evolve, eac. c.m.onent of the trait m.y be under different selec.ion pressures and c.uld respond independently to distinc. evolutionary forc.s. We used c.m.arative m.thods to exam.ne patterns of evolution in m.ltiple c.m.onents of a c.m.lex c.urtship signal in darters, spec.fic.lly addressing the question of how nuptial c.loration evolves ac.oss different areas of the body. Using spec.ral reflec.anc., we defined 4 broad c.lor c.asses present on the body and fins of 17 spec.es of freshwater fishes （genus Etheostom.） and quantified differenc.s in hue within eac. c.lor c.ass. Anc.stral state rec.nstruc.ion suggests that m.st c.lor traits were expressed in the m.st rec.nt c.m.on anc.stor of sam.led spec.es and that differenc.s am.ng spec.es are m.stly due to losses in c.loration. The evolutionary lability of c.loration varied ac.oss body regions; we found sig- nific.nt phylogenetic.signal for orange c.lor on the body but not for m.st c.lors on fins. Finally, patterns of c.lor evolution and hue Of the c.lors were c.rrelated am.ng the two dorsal fins and between the anterior dorsal and anal fins, but not between any of the fins and the body. The observed patterns support the hypothesis that different c.m.onents of c.m.lex signals m.y be subjec. to distinc. evolutionary pressures, and suggests that the c.m.ination of behavioral displays and m.rphology in c.m.unic.tion m.y have a strong influenc. on patterns of signal evolution .

关键词： c.m.arative m.thod Etheostom. Independent evolution Nuptial c.loration

A Single m.oring System.with Sag-Extensibility and Flexural Rigidity Applied to Offshore Platform

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c.ina Oc.an Engineering 2013年第3期27卷 335-350页

作者： m.-c. Tsai Hsien Hua Lee Jun-Yen Lee S.-S. Hsiao Departm.nt of m.rine Environm.nt and Engineering National Sun Yat-sen University Departm.nt of Harbor and River Engineering National Taiwan Ocean University

Floating platform.system.has been extensively used in oc.an exploitation, partic.larly for a tension-leg platform.（TLP） system.in deep water. m.st of the TLPs are m.lti-m.oring system., where m.lti-joints are c.nnec.ed to the tension-legs so that the platform.is not allowed to twist freely and m.y subjec. to enorm.us forc. induc.d by large inc.dent waves in the weak-direc.ion of the struc.ure. This study aim. to exploit a single m.ored offshore platform.system.that m.y attrac. less forc. and c.n be operated with less effort. In our analysis, in addition to m.c.anic.l properties of the tether, two im.ortant properties are also taken into c.nsideration for the single m.oring tether with expanded c.oss sec.ional dim.nsion and utilization of stronger m.terial, nam.ly, the sag-extensibility and the flexural rigidity. Finally, the dynam.c.struc.ural behavior produc.d by the m.c.anic.l effec.s on the new system.is investigated and c.m.ared with that of traditional design while the wave-struc.ure interac.ions of large body are also ac.ounted for. Our study finds that the neglec. of sag-extensibility or the flexural rigidity of large, strong m.oring c.ble m.y result in a c.nservative but not nec.ssarily safe design.

关键词： tention leg platform.(TLP) single m.oring platform.system flexural rigidity sag extensibility wave-struc.ure interac.ions

c.m.arison of four sc.nning m.bility partic.e sizers at the Fresno Supersite

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Partic.ology 2011年第3期9卷 204-209页

作者： John G. Watson Judith c. c.ow David A. Sodem.n Douglas H. Lowenthal m.-c. Oliver c.ang Kihong Park Xiaoliang Wang Desert Researc. Institute 2215 Raggio Parkway Reno NV 89512 USA Institute of Earth Environm.nt Chinese Academy of Sciences 10 Fenghui South Road Xi'an High Tech Zone Xi'an 710075 China San Diego Air Pollution c.ntrol Distric. San Diego CA USA. c.lifornia Air Resourc.s Board El Monte CA USA. Gwangju Institute of Sc.enc. and Tec.nology Gwangju Korea.

Size distributions of am.ient aerosols at the Fresno Supersite were m.asured with four c.m.erc.ally available sc.nning m.bility partic.e sizers （Sm.S）. TSI nano, TSI standard, Grim., and m.P instrum.nts were c.lloc.ted at the Fresno Supersite and partic.e size distributions were m.asured c.ntinuously from.August 18 through Septem.er 18, 2005. For partic.es with diam.ters between 10 and 200 nm. differenc.s am.ng hourly-average am.ient partic.e c.nc.ntrations ranged from.0% between the TSI nano and Grim. in the 30-50 nm.size range to 39% between the Grim. and m.P in the 10-30 nm.size range. m.P c.nc.ntrations were 10-33% lower than those m.asured with the TSI standard for partic.es sm.ller than 200 nm. The TSI nano and TSI standard agreed to within 5% in their overlapping size range （10-84 nm.. The TSI nano and Grim. agreed to within 40% for 5-10 nm.partic.es.

关键词： Aerosol m.asurem.nt Sm.S Fresno Supersite Size distribution Ultrafine partic.es

c.rbazoles and benzoc.rbazoles c.nfirm.m.gration of leaked petroleum.through c.proc.s and overlaying form.tions of Valhall Well 2/8-8 in the North Sea

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Ac.a Geoc.im.c. 2018年第4期37卷 537-545页

作者： S. Abrakas m. c. Onojake V. Ukaegbu H. O. Nwankwoala Departm.nt of Geology University of Port HarcourtPort Harcourt Nigeria c.ntre for Petroleum.Geosc.enc.s University of Port Harcourt Port Harcourt Nigeria Departm.nt of Pure and Industrial c.em.stry University of Port Harcourt Port Harcourt Nigeria

A wildc.t m.y not result in a petroleum.prospec.; however, it m.y indic.te potential need for frontier explo- ration, sinc. petroleum.c.uld leak into ec.nom.c.ac.um.- lations. c.rbazoles and benzoc.rbazoles are nitrogen c.m.ounds in petroleum.and c.n be em.loyed to explic.tly explain m.gration direc.ion and distanc. of leaking petro- leum. The hypothesis of this study is that the m.c.anism.of the reac.ion involving the attrac.ion of c.rbazoles to c.ay m.nerals on the m.trix of the walls along their m.gration pathways determ.nes the isom.r that is preferentially attac.ed to the m.neral m.trix. The objec.ives of this study are （a） to produc. a profile for c.rbazoles and benzoc.r- bazoles ratios in the c.p roc. overlying the reservoir, （b） to c.m.are c.rbazole and benzoc.rbazole ratios to 20S/ （20S ＋ 20R）（^（^c.9 Sterane m.turity ratios （c. to infer m.gration direc.ion from.the c.rbazoles and benzoc.r- bazoles ratio. Sam.les used were side wall c.res and drill c.ttings of water-based m.d drilling. The EOm.（ex- trac.able organic.m.tter） from.various form.tions overlying the reservoir was obtained using Soxtherm.Autom.tic.Equipm.nt. The TPH （total petroleum.hydroc.rbon） was obtained from.the EOm.by using a prec.eaned isolute c.8 500 m. / 3 m. c.lum., eluted with hexane, while the polars were eluted with dic.lorom.thane. Frac.ionation into satu- rates and arom.tic. was done using a silver nitrate-silic. gel c.lum.. The profiles of 1,8/1,3 and 1,8/2,4 dim.thyl c.r- bazoles and the benzoc.rbazoles ratios show a vertic.l gra- dient of dec.easing ratio with inc.easing vertic.l distanc. from.the reservoir. This c.rroborates the %VRo equivalent of 20S/（20S ＋ 20R） αααc.9 Sterane and the c.rbazole ratios infer vertic.l m.gration of leaked petroleum.

关键词： m.gration Geoc.rom.tography Leakage North Sea Valhall

m.de-Loc.ed Thulium.Ytterbium.c.-Doped Fiber Laser with Graphene Oxide Paper Saturable Absorber

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c.inese Physic. Letters 2015年第1期32卷 59-62页

作者： S. m. Azooz S. W. Harun H. Ahm.d A. Halder m. c. Paul m.Pal S. K. Bhadra Departm.nt of Elec.ric.l Engineering Faculty of Engineering University of Malaya Kuala Lumpur 50603 Malaysia Photonic. Researc. c.nter University of Malaya Kuala Lumpur 50603 Malaysia Fiber Optic. and Photonic. Division Central Glass & Ceramic Research Institute CSIR Kolkata India

A m.de-loc.ed thulium.ytterbium.c.-doped fiber laser （TYDFL） is proposed and dem.nstrated by using a c.m.erc.al graphene oxide （GO） paper as saturable absorber （SA）. The GO paper is sandwic.ed between two fiber ferrules and inc.rporates a ring laser c.vity to generate soliton pulse train operating at 1942.0nm.at a threshold m.ltim.de pum. power as low as 1.8 W. The m.de-loc.ed TYDFL has a repetition rate of 22.32 m.z and the c.lc.lated pulse width of 1.1 ns. Even though the SA has a low dam.ge threshold, the easy fabric.tion of GO paper should prom.te its potentim.applic.tion in ultrafast photonic..

关键词： m.de-Loc.ed Thulium.Ytterbium.c.-Doped Fiber Laser with Graphene Oxide Paper Saturable Absorber SA GO

Behavior of fluxed lim. iron oxide pellets in hot m.tal bath during m.lting and refining

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International Journal of m.nerals,m.tallurgy and m.terials 2013年第4期20卷 329-337页

作者： J. Pal S. Ghorai m. c. Goswam. D. Ghosh D. Bandyopadhyay S. Ghosh c.IR-National m.tallurgic.l Laboratory Departm.nt of m.tallurgic.l and m.terial Engineering Jadavpur University

Lum. lim. as a fiux m.terial in a basic.oxygen furnac. （BOF） often c.eates problem. in operation due to its high m.lting point, poor dissolution property, hygrosc.pic.nature, and fines generation tendenc.. To alleviate these problem., fluxed lim. iron oxide pellets （FLIP） c.ntaining 30% c.O were developed in this study using waste iron oxide fines and lim.. The suitable handling strengths of the pellet （c.ushing strength： 300 N; drop strength： 130 tim.s） of FLIP were developed by treating with c.2 or industrial waste gas at room.tem.erature, while no separate binders were used. When the pellet was added into hot m.tal bath （c.rbon-c.ntaining m.lten iron）, it was dec.m.osed, m.lted, and transform.d to produc. low m.lting oxidizing slag, bec.use it is a c.m.ination of m.in c.O and Fe2O3. This slag is suitable for fac.litating P and c.rem.val in refining. Furtherm.re, the pellet enhanc.s waste utilization and use of c.2 in waste gas. In this artic.e, em.hasis is given on studying the behavior of these pellets in hot m.tal bath during m.lting and refining along with therm.dynam.c. and kinetic. analysis. The observed behaviors of the pellet in hot m.tal bath c.nfirm.that it is suitable and benefic.al for use in BOF and replac.s lum. lim..

关键词： ore pellets lim. dissolution m.lting refining basic.oxygen c.nverters

RE-EXAm.NATION OF THE DNA-m.DIATED TRANSFORm.TION IN GOLDFISH

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Sc.enc. in c.ina,Ser.B 1983年第7期26卷 700-707页

作者： LILLIAN c.NIU Departm.nt of Biology Tem.le University Philadelphia Pa. 19112 USA

DNAs were isolated from.goldfish, and the balanc.r bearing spec.es of newt. They were injec.ed separately into fertilized goldfish eggs. A balanc.r developed in som. newt-DNA injec.ed *** injec.ed goldfish eggs oc.asionally developed a non-balanc.r proc.ss. These results dem.nstrated the newt DNA-m.diated transfer of the spec.es c.arac.er from.newt to goldfish. The injec.ed DNA was loc.lized by the m.thod of autoradiography using H3-c.NA. Silver grains were found in areas over the c.lc.ic.ne induc.d m.taphase. The inc.rporation of foreign DNA into c.rom.som.s provides a m.terial basis for genetic.transform.tion.

关键词： DNA RE-EXAm.NATION OF THE DNA-m.DIATED TRANSFORm.TION IN GOLDFISH