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Crystalli.ati.n and i.pact hi.tory of a meteori.i. sample of early lunar crust(NWA 3163)refi.ed by atom probe geochronology

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Geosci.nce Fronti.rs 2019年第5期10卷 1841-1848页

作者： L.F. Whi.e D.E. Moser K.T. Tai. B. Langeli.r i. barker J.R. Darli.g Centre for Appli.d Planetary Mi.eralogy Department of Natural HistoryRoyal Ontario MuseumTorontoOntarioM5S 2C6Canada Department of Earth Sci.nces University of TorontoTorontoOntarioM5S 3B1Canada Department of Earth Sci.nces University of Western OntarioLondonN6A 5B7Canada Canadi.n Centre for Electron Mi.roscopy McMaster UniversityHamiltonOntarioCanada School of Earth and Envi.onmental Sci.nce University of PortsmouthPortsmouthUK

Granuli.i. lunar meteori.es offer rare i.si.hts i.to the ti.i.g and nature of i.neous,metamorphi. and i.pact processes i. the lunar *** dati.g the di.ferent events recorded by these materi.ls i. very challengi.g,however,due to low trace element abundances (***,Nd,Lu,Hf),rare mi.rometerscale U-Th-beari.g accessory mi.erals,and di.turbed Ar-Ar systemati.s followi.g a multi.stage hi.tory of shock and thermal *** we report on mi.ro-baddeleyi.e grai.s i. granuli.i. mafi. brecci. NWA 3163 for the fi.st ti.e and show that targeted mi.rostructural analysi. (electron backscatter di.fracti.n) and nanoscale geochronology (atom probe tomography) can overcome these barri.rs to lunar chronology.A twi.ned (-90°/) baddeleyi.e domai. yi.lds a 232Th/208Pb age of 4328 ± 309 Ma,whi.h overlaps wi.h a robust secondary i.n mass spectrometry (Si.S) 207Pb/206Pb age of 4308± 18.6 Ma and i. i.terpreted here as the crystalli.ati.n age for the i.neous protoli.h of NWA 3163.A second mi.rostructural domai.,i. wi.th,contai.s patchy overpri.ti.g baddeleyi.e and yi.lds a Th-Pb age of 2175± 143 Ma,i.terpreted as dati.g the last substanti.l i.pact event to affect the *** fi.di.g demonstrates the potenti.l of combi.i.g mi.rostructural characteri.ati.n wi.h nanoscale geochronology when resolvi.g complex P-T-t hi.tori.s i. planetary materi.ls,here yi.ldi.g the oldest measured crystalli.ati.n age for components of lunar granuli.e NWA 3163 and placi.g further constrai.ts on the formati.n and evoluti.n of lunar crust.

关键词： Baddeleyi.e U-Th-Pb i.otopes EBSD Atom probe tomography Geochronology Northwest Afri.a 3163

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Sampli.g-Based Approaches to Esti.ati.g Two-Di.ensi.nal Large Wood Area from UAS i.agery

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Journal of Geographi. i.formati.n System 2022年第6期14卷 571-588页

作者： Matthew i. barker Jonathan D. Burnett Franci.co Mauro Guti.rrez Steven M. Wondzell Mi.hael G. Wi.g Forest Engi.eeri.g Resources and Management Department College of Forestry Oregon State University Corvallis OR USA USDA Forest Servi.e Pacific Northwest Research Station Corvallis OR USA Ei.AB—i.FOR Campus Duques de Soria s/n Universidad de Valladolid Soria Spain

Large i.-stream wood (LW) i. a cri.i.al component of ri.ari.n systems that i.creases heterogenei.y of flow regi.es and provi.es hi.h quali.y habi.at for salmoni.s and other fi.hes. We present four sampli.g-based methods to esti.ate two-di.ensi.nal LW for a 61-hectare ri.er restorati.n project on the South Fork McKenzi. Ri.er near Rai.bow, OR (USA). We manually deli.eated LW area, from unoccupi.d ai.craft systems (UAS) multi.pectral i.agery for 40 randomly selected 51.46 m2 hexagonal plots. Seven auxi.i.ry vari.bles were extracted from the i.agery and i.agery deri.ati.es to be i.corporated i. four esti.ators by summari.i.g spectral stati.ti.s for each plot i.cludi.g Random forest (RF) classi.i.ati.n of segmented i.agery (Cohen’s kappa = 0.75, balanced accuracy = 0.86). The four esti.ators were: di.ference esti.ator, si.ple li.ear regressi.n esti.ator wi.h one auxi.i.ry vari.ble, general regressi.n esti.ator wi.h seven auxi.i.ry vari.bles, and si.ple random sample wi.hout replacement. We assessed vari.nce of the esti.ators and found that the si.ple random sample wi.hout replacement produced the largest esti.ate for LW area and wi.est confi.ence i.terval (17,283 m2, 95% Ci.10,613 - 23,952 m2) whi.e the generali.ed regressi.n approach resulted i. the smallest esti.ate and narrowest confi.ence i.terval (16,593 m2, 95% Ci.13,054 - 20,133 m2). These methods faci.i.ate effi.i.nt esti.ates of cri.i.al habi.at components, that are especi.lly sui.ed to efforts that seek to quanti.y large amounts of these components through ti.e. When combi.ed wi.h tradi.i.nal sampli.g methods, classi.i.d i.agery acqui.ed vi. UAS promi.es to enhance the temporal resoluti.n of the data products associ.ted wi.h restorati.n efforts whi.e mi.i.i.i.g the necessi.y for potenti.lly hazardous fi.ld work.

关键词： UAS Large i.-Stream Wood Sampli.g i.age Classi.i.ati.n Ri.er Restorati.n

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埋弧电炉用的电极控制装置

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铁合金 1981年第3期 43-49页

作者： i. J. barker 李大达南非冶金研究院

为了解决大型埋弧电炉生产问题所需的某些设备,南非冶金研究院研制出一种新型的埋弧电炉用的电极控制装置。本文论述了这一原型装置运算方法的发展,阐述了传统的电极控制中问题的实质,描述了这一原型装置的操作。

关键词：埋弧电炉冶金研究院还原电炉电弧炉电极控制原型装置

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Moni.ori.g the 2008 cold surge and frozen di.asters snowstorm i. South Chi.a based on regi.nal ATOVS data assi.i.ati.n

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Sci.nce Chi.a Earth Sci.nces 2010年第8期53卷 1216-1228页

作者： DALE M.barker Nati.nal Center for Atmospheri. Research BoulderColoradoUSA

i. January 2008, South Chi.a experi.nced extremely low temperatures, heavy snowstorms, and severe frosts (2008 Frost Di.aster, for short), whi.h led to (parti.l) fai.ures of observati.ns from ground stati.ns and ground radars resulti.g i. a lack of necessary emergency i.formati.n. To compensate for the fai.ure of ground observati.ns and to provi.e ti.ely di.aster i.formati.n, the Nati.nal Satelli.e Meteorologi.al Center of Chi.a (NSMC) establi.hed a snow storm moni.ori.g system for the 2008 Frost Di.aster, whi.h was based on the WRF Three Di.ensi.n Vari.ti.nal Assi.i.ati.n and Forecast system (wi.h NOAH as the land surface sub-process model) cooperati.ely developed by NSMC and the Nati.nal Center for Atmospheri. Research (NCAR), US. Thi. system made full use of ATOVS and NCEP data to provi.e esti.ates of snow water equi.alent every 6 hours duri.g the storm. i. thi. study, the ATOVS assi.i.ati.n based snowstorm moni.ori.g scheme was explored i. detai., whi.e the modeled results wi.h and wi.hout ATOVS assi.i.ati.n were compared agai.st related observati.ns. Results showed that the coupli.g of ATOVS assi.i.ati.n i.to the proposed moni.ori.g system evi.ently deli.eates weather characteri.ti.s of the snowstorm process more accurately, and demonstrated the feasi.i.i.y of the system for snowstorm moni.ori.g and forecasti.g. Through theoreti.al analyses and case di.cussi.n, thi. study proposes a reli.ble and practi.able scheme to provi.e ti.ely and accurate i.formati.n on snow spati.l di.tri.uti.n and temporal development for di.aster mi.i.ati.n, and i.lustrates a new appli.ati.n of ATOVS data.

关键词： 2008 cold surge and frozen di.aster i. South Chi.a ATOVS data assi.i.ati.n snow depth snowstorm moni.ori.g

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Compari.ons of corrosi.n behavi.ur for X65 and low Cr steels i. hi.h pressure CO2-saturated bri.e

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Journal of Materi.ls Sci.nce & Technology 2020年第6期41卷 21-32页

作者： Yong Hua Si.i.u Mohammed Ri.hard barker Anne Nevi.le i.sti.ute of Functi.nal Surfaces School of Mechanical Engineering University of Leeds Leeds LS2 9JT United Kingdom

Appropri.te materi.ls for i.jecti.n pi.eli.es and tubi.g for carbon di.xi.e geologi. storage i. fundamental to ensure asset i.tegri.y and save *** paper evaluates the corrosi.n behavi.ur of X65,1Cr,3Cr and 5Cr,whi.h have the potenti.l to be i.jecti.n pi.eli.e/tubi.g *** i.fluence of steel Cr content on the general and locali.ed corrosi.n behavi.ur was i.vesti.ated at ti.e peri.ds from 6 to 192 h at 60℃and 100 *** evoluti.n,morphology and chemi.try of corrosi.n products on the surface of each materi.l were evaluated usi.g a combi.ati.n of scanni.g electron mi.roscopy,energy di.persi.e X-ray spectroscopy and X-ray di.fracti.n and related to thei. overall corrosi.n *** i.di.ate that pri.r to the formati.n of protecti.e fi.ms on the steel surfaces,the resi.tance of the materi.ls to corrosi.n i.crease wi.h i.creasi.g Cr content(Corrosi.n resi.tance:X65i.n products evolve,the protecti.n afforded to the di.ferent steels si.ni.i.antly vari.s and decreases wi.h i.creasi.g Cr content.×65 becomes the materi.l wi.h the lowest general corrosi.n rate by the end of the 192 h experi.ents and 5Cr exhi.i.s the hi.hest corrosi.n rate(ranki.g of corrosi.n resi.tance:X65>1Cr>3Cr>5Cr).i. terms of the corrosi.n products on X65,both i.ner amorphous and outer crystalli.e corrosi.n layers consi.t of *** the Cr-contai.i.g steels,the outer layer also compri.es FeCO3,but the i.ner layer i. enri.hed wi.h Cr,and i. predomi.antly amorphous Cr(OH)*** extent of locali.ed corrosi.n(determi.ed usi.g surface profi.ometry)i. noti.eably less for X65 compared to the Cr-contai.i.g *** paper rai.es questi.ns about the benefi.s that low Cr steels offer towards extendi.g component desi.n li.e compared to carbon steel under the test condi.i.ns consi.ered here.

关键词： Carbon di.xi.e Corrosi.n X65 Low-Cr steels i.on carbonate Chromi.m hydroxi.e

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EXi.TENCE AND STABi.i.Y OF Vi.COUS SHOCK PROFi.ES FOR 2-D i.ENTROPi. MHD Wi.H i.Fi.i.E ELECTRi.AL RESi.Ti.i.Y

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Acta Mathemati.a Sci.nti. 2010年第2期30卷 447-498页

作者： Blake barker Oli.i.r Lafi.te Kevi. Zumbrun Department of Mathemati.s Indiana University LAGA Institut GalileeUniversite Paris 1393 430 Villetaneuse and CEA SaclayDM2S/DIR91 191 Gif sur Yvette CedexFrance

For the two-di.ensi.nal Navi.r-Stokes equati.ns of i.entropi. magnetohydrodynami.s （MHD） wi.h γ-law gas equati.n of state, γ≥ 1, and i.fi.i.e electri.al resi.ti.i.y, we carry out a global analysi. categori.i.g all possi.le vi.cous shock profi.es. Preci.ely, we show that the phase portrai. of the traveli.g-wave ODE generi.ally consi.ts of ei.her two rest poi.ts connected by a vi.cous Lax profi.e, or else four rest poi.ts, two saddles and two nodes. i. the latter confi.urati.n, whi.h rest poi.ts are connected by profi.es depends on the rati. of vi.cosi.i.s, and can i.volve Lax, overcompressi.e, or undercompressi.e shock profi.es. Consi.ered as three-di.ensi.nal soluti.ns, undercompressi.e shocks axe Lax-type （Alfven） waves. For the monatomi. and di.tomi. cases γ= 5/3 and γ=7/5, wi.h standard vi.cosi.y rati. for a nonmagneti. gas, we fi.d numeri.ally that the the nodes are connected by a fami.y of overcompressi.e profi.es bounded by Lax profi.es connecti.g saddles to nodes, wi.h no undercompressi.e shocks occurri.g. We carry out a systemati. numeri.al Evans functi.n analysi. i.di.ati.g that all of these two-di.ensi.nal shock pro- fi.es are li.early and nonli.early stable, both wi.h respect to two- and three-di.ensi.nal perturbati.ns. For the same gas constants, but di.ferent vi.cosi.y rati.s, we i.vesti.ate also cases for whi.h undercompressi.e shocks appear; these are seen numeri.ally to be stable as well, both wi.h respect to two-di.ensi.nal and （i. the neutral sense of convergence to nearby Ri.mann soluti.ns） three-di.ensi.nal perturbati.ns.

关键词： stabi.i.y of vi.cous shock waves Evans functi.n magnetohydrodynami.s

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Physi.logy of medi.i.al and aromati. plants under drought stress

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The Crop Journal 2024年第2期12卷 330-339页

作者： Zohreh Emami.Bi.tgani.Allen V.barker Masoud Hashemi i.fahan Agri.ultural and Natural Resources Research and Educati.n Center Agricultural Research Education and Extension Organization(AREEO)Isfahan 81748-35117Iran Stockbri.ge School of Agri.ulture University of MassachusettsAmherstMA 01002USA

Drought poses a si.ni.i.ant challenge,restri.ti.g the producti.i.y of medi.i.al and aromati. *** strai. i.duced by drought can i.pede vi.al processes li.e respi.ati.n and photosynthesi.,affecti.g vari.us aspects of plants’growth and *** response to thi. adversi.y,medi.i.al plants employ mechani.ms such as morphologi.al and structural adjustments,modulati.n of drought-resi.tant genes,and augmented synthesi. of secondary metaboli.es and osmoti. regulatory substances to allevi.te the *** water scarci.y can lead to leaf wi.ti.g and may ulti.ately result i. plant *** culti.ati.n and management of medi.i.al plants under stress condi.i.ns often di.fer from those of other *** i. because the mai. goal wi.h medi.i.al plants i. not only to i.crease the yi.ld of the above-ground parts but also to enhance the producti.n of acti.e i.gredi.nts such as essenti.l *** eluci.ate these mechani.ms of drought resi.tance i. medi.i.al and aromati. plants,the current revi.w provi.es a summary of recent li.erature encompassi.g studi.s on the morphology,physi.logy,and bi.chemi.try of medi.i.al and aromati. plants under drought condi.i.ns.

关键词： Drought stress Medi.i.al and aromati. plants Phytochemi.try Physi.logy

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Conti.ued surpri.es i. the cytochrome c bi.genesi. story

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Protei. & Cell 2012年第6期3卷 405-409页

作者： Eli.abeth B.Sawyer Paul D.barker Nati.nal Laboratory of Bi.macromolecules Institute of BiophysicsChinese Academy of SciencesBeijing 100101China Uni.ersi.y Chemi.al Laboratory University of CambridgeCambridgeCB21EWUnited Kingdom

Cytochromes c covalently bi.d thei. heme prostheti. groups through thi.ether bonds between the vi.yl groups of the heme and the thi.ls of a CXXCH moti. wi.hi. the *** Gramnegati.e bacteri.,thi. process i. catalyzed by the Ccm(cytochrome c maturati.n)protei.s,also called System *** Ccm protei.s are found i. the bacteri.l i.ner membrane,but some(CcmE,CcmG,CcmH,and Ccmi.also have soluble functi.nal domai.s on the peri.lasmi. face of the *** of the mechani.ms i.volved i. the transport and relay of heme and the apo-cytochrome from the bacteri.l cytosol i.to the peri.lasm,and thei. subsequent reacti.n,has proved challengi.g due to the fact that most of the protei.s i.volved are membrane-associ.ted,but recent progress i. understandi.g some key components has thrown up some *** thi. Revi.w,we di.cuss advances i. our understandi.g of thi. process ari.i.g from a substrate’s poi.t of vi.w and from recent structural i.formati.n about i.di.i.ual components.

关键词： cytochrome c heme Ccm post-transla-ti.nal modi.i.ati.n cytochrome b562 heme bi.di.g

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AFast Solver for an H_(1) Regulari.ed PDE-Constrai.ed Opti.i.ati.n Problem

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Communi.ati.ns i. Computati.nal Physi.s 2016年第1期19卷 143-167页

作者： Andrew T.barker Tyrone Rees Marti. Stoll Center for Appli.d Sci.nti.i. Computi.g Lawrence Livermore National LaboratoryMail Stop L-561LivermoreCA 94551USA Numeri.al Analysi. Group Scientific Computing DepartmentRutherford Appleton LaboratoryChiltonDidcotOxfordshireOX110QXUnited Kingdom Computati.nal Methods i. Systems and Control Theory Max Planck Institute for Dynamics of Complex Technical SystemsSandtorstr.139106MagdeburgGermany

i. thi. paperwe consi.er PDE-constrai.ed opti.i.ati.n problemswhi.h i.corporate an H_(1)regulari.ati.n control *** focus on a ti.e-dependent PDE,and consi.er both di.tri.uted and boundary *** problems we consi.er i.clude bound constrai.ts on the state,and we use a Moreau-Yosi.a penalty functi.n to handle *** propose Krylov solvers and Schur complement precondi.i.ni.g strategi.s for the di.ferent problems and i.lustrate thei. performance wi.h numeri.al examples.

关键词： Precondi.i.ni.g Krylov methods PDE-constrai.ed opti.i.ati.n opti.al control of PDEs

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Envi.onmental temperatures,physi.logy and behavi.r li.i. the range expansi.n of i.vasi.e Burmese pythons i. southeastern USA

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i.tegrati.e Zoology 2012年第3期7卷 271-285页

作者： Elli.tt R.JACOBSON Davi. G.barker Tracy M.barker Ri.hard MAULDi. Mi.hael L.AVERY Ri.hard ENGEMAN Stephen SECOR College of Veteri.ary Medi.i.e University of FloridaGainesvilleFlorida Vi.a Preci.sa i.ternati.nal(VPi. BoerneTexas US Department of Agri.ulture Wildlife ServicesNational Wildlife Research CenterFort CollinsColorado US Department of Agri.ulture Wildlife ServicesNational Wildlife Research CenterGainesvilleFlorida Department of Bi.logi.al Sci.nces University of AlabamaTuscaloosaAlabamaUSA

A well-establi.hed populati.n of Burmese pythons resi.es i. the Everglades of southern *** i. part by a report that i.enti.i.d much of southern USA as sui.able habi.at for expansi.n or establi.hment of the Burmese python,we exami.ed the plausi.i.i.y of thi. snake to survi.e wi.ters at si.es north of the *** i.tegrated dai.y low and hi.h temperatures recorded from October to February from 2005-2011 at Homestead,Orlando and Gai.esvi.le,Flori.a;and Ai.en,South Caroli.a,wi.h mi.i.um temperatures projected for python di.esti.n(16℃),acti.i.y(5℃)and survi.al(0℃).Mean low and hi.h temperatures decreased northward from Homestead to Ai.en and the number of days of freezi.g temperatures i.creased *** was i.pai.ed or i.hi.i.ed for 2 months i. the Everglades and up to at least 5 months i. Ai.en,and acti.i.y was i.creasi.gly li.i.ed northward duri.g these *** of overwi.ter survi.orshi. document that a si.gle bout of low and freezi.g temperatures results i. python *** capaci.y for Burmese pythons to successfully overwi.ter i. more temperate regi.ns of the USA i. seemi.gly prohi.i.ed because they lack the behavi.rs to seek refuge from,and the physi.logy to tolerate,cold *** tropi.al Southeast Asi. i. the source of the Everglades Burmese pythons,we predi.t i. i. unli.ely that they wi.l be able to successfully expand to or coloni.e more temperate areas of Flori.a and adjoi.i.g states due to thei. lack of behavi.ral and physi.logi.al trai.s to seek refuge from cold temperatures.

关键词： ambi.nt temperature Burmese python i.vasi.n snake thermal tolerance

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