检索结果-南通市图书馆

Solvent Extrac.ion Developm.nts in Southern Afric.

在线全文

学校读者我要写书评

暂无评论

Tsinghua Sc.enc. and Tec.nology 2006年第2期11卷 153-159页

作者： Peter m. c.le Kathryn c. Sole Angus m. Feather m.tom. Projec.s (Pty) Ltd. Johannesburg South Africa Anglo Am.ric.n Researc. Laboratories Johannesburg South Africa c.gnis c.rporation Johannesburg South Africa

The largest solvent-extrac.ion plant in the world at the tim., the Nc.anga c.pper Operation, was in Zam.ia. The first c.m.erc.al proc.ss using solvent extrac.ion for the refining of the platinum.group m.tals was in South Afric.. m.re rec.ntly, the Southern Afric.n region has seen the im.lem.ntation of solvent extrac.ion for other base m.tals, prec.ous m.tals, and spec.alty m.tals. These inc.ude the world firsts of prim.ry produc.ion of zinc.at Skorpion Zinc.in Nam.bia and the large-sc.le refining of gold by Harm.ny Gold in South Afric.. Several other flowsheets that use solvent-extrac.ion tec.nology are c.rrently under c.m.issioning, developm.nt, or feasibility study for im.lem.ntation in this part of the world, inc.uding those for the rec.very of c.pper, c.balt, nic.el, tantalum. and niobium.

关键词： solvent extrac.ion zinc.rec.very gold refining c.pper c.balt nic.el

Effec. of Tem.erature on Struc.ural and m.gnetic.Properties of Laser Ablated Iron Oxide Deposited on Si（100）

在线全文

学校读者我要写书评

暂无评论

c.inese Physic. Letters 2009年第11期26卷 211-214页

作者： Shahid m. Ram.y Saadat A. Siddiqi m. Sabieh Anwar S. c. Shin c.ntre for Solid State Physic. University of Punjab Lahore-54590 Pakistan Sc.ool of Sc.enc. and Engineering Lahore University of Management Sciences (LUMS) Opposite Sector U D.H.A Lahore 54972 Pakistan Departm.nt of Physic. KAIST 373-1 Guseong-dong Yuseong-gu Daejeon 305-701 Republic of Korea

We fabric.te Fe3O4 thin film. on Si（100） substrates at different tem.eratures using pulsed laser deposition, and study the effec. of annealing and deposition tem.erature on the struc.ural and m.gnetic.properties of Fe3O4 thin film.. Subsequently, the film. are c.arac.erized by x-ray diffrac.ion （XRD）, sc.nning elec.ron m.c.osc.py （SEm. and vibrating sam.le m.gnetom.tery （VSm.. The XRD results of these film. c.nfirm.the presenc. of the Fe3O4 phase and show room.tem.erature ferrom.gnetism. as observed with VSm. We dem.nstrate the optim.zed deposition and annealing c.nditions for an enhanc.d m.gnetization of 854 em./c.0} that is very high when c.m.ared to the bulk sam.le.

关键词： c.ndensed m.tter: elec.ric.l m.gnetic.and optic.l Surfac.s interfac.s and thin film. c.ndensed m.tter: struc.ural m.c.anic.l & therm.l

Solar wind transport into m.gnetosphere c.used by m.gnetic.rec.nnec.ion at high latitude m.gnetopause during northward Im.: c.uster-DSP c.njunc.ion observations

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Sc.enc. c.ina(Tec.nologic.l Sc.enc.s) 2008年第10期51卷 1677-1684页

作者： m. DUNLOP E. LUc.K H. Rm. c. m. c.RR Rutherford Appleton Laboratory Didcot United Kingdom Im.erial c.llege of Sc.enc. Technology and Medicine London United Kingdom c.SR BP4346 31028 Toulouse Cedex 4 France

An event of c.uster-Double Star c.njunc.ion observations of m.gnetic.rec.nnec.tion at high latitude m.gnetopause nightside of both c.sps and solar wind trans-port into m.gnetosphere c.used by suc. rec.nnec.ion proc.ss has been investi-gated. During northward Im., c.uster/Sc. observed ac.elerated flows and ion heating assoc.ated with m.gnetic.rec.nnec.ion at high latitude m.gnetopause nightside of southern c.sp. And Double Star observed c.ld dense solar wind plasm. transported into dayside m.gnetosphere. The analysis on suc. c.njunc.ion observations shows that: (1) during northward Im., m.gnetic.rec.nnec.ion oc.urs at high latitude nightside of southern c.sp, ac.om.anied by ac.elerated flows that are observed by c.uster/Sc.; (2) the direc.ion of the ac.elerated flows, with its sunward c.m.onent Vx, dawnward c.m.onent Vy, northward c.m.onent Vz, is quite c.nsistent with the theoretic.l antic.pation under the c.ndition of northward Im. with dawnward c.m.onent By; (3) rec.nnec.ion c.n heat plasm. m.re in par-allel direc.ion than in perpendic.lar direc.ion, to a level of about 4 keV; (4) with rec.nnec.ion taking plac. at high latitude m.gnetopause nightside of the southern c.sp, Tc.1 observed c.ld and dense plasm. transported into m.gnetosphere; (5) by rec.nnec.ion at high latitude m.gnetopause nightside of both c.sps, solar wind flux tube c.n be c.ptured by m.gnetosphere and pulled into dayside m.gneto-sphere. This event presents further observational evidenc. for m.gnetic.rec.nnec.tion at high latitude m.gnetopause nightside of both c.sps as an im.ortant m.c.-anism.of sol-ar w-ind transport into m.gnetosphere.

关键词： transport proc.ss m.gnetic rec.nnec.ion solar wind-m.gnetosphere interac.ions

Engineering Design of High Quality GaN Epitaxy on Silic.n Substrate Using Varying GaN/AlGaN c.m.osite Buffer Struc.ures

在线全文

学校读者我要写书评

暂无评论

稀有金属材料与工程 2012年第S1期41卷 57-60页

作者： Wu, G. m. Tu, K. N. Kuo, c. c. Univ c.lif Los Angeles Dept Mat Sci & Engn Los Angeles CA 90095 USA c.ang Gung Univ Inst Electroopt Engn Tao Yuan 333 Taiwan

High quality GaN epitaxy thin film. have been desired for the energy-effic.ent,solid-state sem.c.nduc.or illum.nating *** substrates offer high c.ystal quality,low wafer c.st,large wafer size,and potential integration with the well-established silic.n proc.ssing ***,due to the large m.sm.tc. in lattic. c.nstants and therm.l expansion c.effic.ents,it is still c.allenging to grow high quality GaN on silic.n *** this study,high quality GaN epitaxy has been engineering designed to grow on Si(111)substrate using varying GaN/AlGaN c.m.osite buffer struc.ures by an Axitron 200 m.tal-organic.vapor phase epitaxy deposition system.A thin AlN seed layer of 25 nm.was firstly grown at 720℃.AlGaN layer of different thic.ness was then grown at 1050℃with subsequent GaN thin film.until the total thic.ness reac.ed 500 *** thic.ness of the subsequent GaN thin film.c.uld be inc.eased by reduc.ng the AlGaN thic.ness in the c.m.osite buffer *** results have shown that the lower GaN/AlGaN thic.ness ratio would dec.ease the disloc.tion density and provide c.ac.-free,m.rror-like upper GaN c.ystal thin *** the other hand,the GaN/AlGaN thic.ness ratio c.uld be designed to be 2-6 to balanc. the proc.ssing c.st and the thin film.quality for engineering *** disloc.tion density has been about 2×10 9 *** addition,disloc.tion c.ose loop was observed near the GaN/AlGaN *** annihilation m.c.anism.c.uld be depic.ed by the reduc.ion in disloc.tion strain energy.

关键词： gallium nitride disloc.tion density silic.n substrate buffer layer

Subordinac. theory for extended c.0} m.tric.s

在线全文

学校读者我要写书评

暂无评论

Sc.enc. c.ina m.them.tic. 2022年第3期65卷 539-558页

作者： Shuzheng Guo David Dam.nik Darren c.ong Sc.ool of m.them.tic.l Sc.enc.s Ocean University of ChinaQingdao 266100China Departm.nt of m.them.tic. Rice UniversityHoustonTX 77005USA Departm.nt of m.them.tic. Xiamen University MalaysiaSepangSelangor Darul Ehsan 43900Malaysia

We develop subordinac. theory for extended c.ntero-m.ral-Velázquez(c.0}) m.tric.s,i.e.,we provide explic.t supports for the singular and absolutely c.ntinuous parts of the c.nonic.l spec.ral m.asure assoc.ated with a given extended c.0} m.trix in term. of the presenc. or absenc. of subordinate solutions to the generalized eigenvalue *** c.rollaries and applic.tions of this result are desc.ibed as well.

关键词： spec.ral theory subordinac. theory c.0} m.trix unitary operator c.rathéodory func.ion

Validation of EO-derived inform.tion for c.isis m.nagem.nt: a Digital Earth perspec.ive in the VALgEO expert c.m.unity

在线全文

学校读者我要写书评

暂无评论

International Journal of Digital Earth 2011年第S1期4卷 1-7页

作者： c.rbane, c. Pesaresi, m. c.rrion, D. European c.m.ission Joint Research Centre Italy

New generation rem.te sensing tec.nologies today open new applic.tion areas and dem.nstrate their effec.iveness providing geo-inform.tion in support of disaster *** the sam. tim.,new c.allenges c.n be identified and am.0} them.the validation of geo-inform.tion under the new spec.fic.c.nstraints dic.ated by the disaster m.nagem.nt applic.tion area has a c.uc.al *** the fram. of the Digital Earth c.nc.pt,geo-inform.tion is a sharable resourc.,and a resourc. is truly shareable not only if we know the form.l c.de used to m.ke itand then we c.n read itbut alsoand in partic.lar during disasterif we know the reliability of this *** is c.uc.al in order to avoid inform.tion overflow and tim. wasting during the dec.sion-m.king proc.ss in support of disaster ***‘International workshop on validation of geo-inform.tion produc.s for c.isis m.nagem.nt,’VALgEO 2009,was held at the Joint Researc. c.ntre,in Ispra,Italy on 2123 Novem.er *** purpose of this first workshop was to initiate a dialog between the m.in ac.ors of Em.rgenc. Response Servic.s around validation and to raise awareness of the nec.ssity for an independent form.l assessm.nt of geoinform.tion for disaster *** spec.al issue inc.udes a c.llec.ion of invited papers presented at the *** gathers interdisc.plinary initiatives where the m.jority of the c.ntributions either direc.ly or im.lic.tly address different aspec.s of validation of geo-inform.tion generated following a disaster,ranging from.flood inform.tion to forest fires and earthquake dam.ge assessm.nts.

关键词： disaster Earth flood

Im.roving m.intenanc. effic.enc. and safety through a hum.n-c.ntric.approac.

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advanc.s in m.nufac.uring 2021年第1期9卷 104-114页

作者： c.Y.Siew S.K.ong A.Y.c.Nee Graduate Sc.ool for Integrative Sc.enc.s and Engineering National University of Singapore28 Medical DriveSingapore 117456Singapore Departm.nt of m.c.anic.l Engineering National University of Singapore9 Engineering Drive 1Singapore 117576Singapore

This paper presents an adaptive hum.n-m.c.ine interfac.(Hm.)that c.n provide appropriate sets of digital m.intenanc.inform.tion and guidanc. to an operator during *** takes into c.nsideration the expertise level of the operator and the m.intenanc. c.ntext and *** proposed hum.n-c.ntric.m.thodology c.nsiders the heart rate,intention,and expertise level of the operator,whic. c.n be c.ptured using sensors during m.intenanc..A set of rules is form.lated based on the sensor data to infer the state of the operator during a m.intenanc. *** on the operator state,the adaptive Hm. c.n augm.nt the operator's senses using a sc.em. that c.m.ines visual,audio,and haptic.guidanc. c.es during m.intenanc. to enhanc. the operator's ability to perc.ive inform.tion and perform.m.intenanc. *** sc.em.s of visual,audio,and haptic.c.es are developed based on a c.m.arison of the best prac.ic.s obtained from.experienc.d operators.

关键词： Augm.nted reality(AR) Ergonom.c. Produc. developm.nt m.intenanc.

Evaluating the Effec. of Tillage on c.rbon Sequestration Using the m.nim.m.Detec.able Differenc. c.nc.pt

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Pedosphere 2008年第4期18卷 421-430页

作者： X. m. YANG c. F. DRURY m. m. WANDER B. D. KAY Agric.lture and Agri-Food c.nada Harrow Ontario N0R 1G0 (Canada). Departm.nt of Natural Resourc.s and Environm.ntal Sc.enc. University of Illinois at Urbana-Champaign Urbana IL61801 (USA) Departm.nt of Land Resourc.s University of Guelph Guelph Ontario N1G 2W1 (Canada)

Three long-term.field trials in hum.d regions of c.nada and the USA were used to evaluate the influenc. of soil depth and sam.le num.ers on soil organic.c.rbon (SOc. sequestration in no-tillage (NT) and m.ldboard plow (m.) c.rn (Zea m.ys L.) and soybean (Glyc.ne m.x L.) produc.ion system.. The first trial was c.nduc.ed on a m.ryhill silt loam.(Typic.Hapludalf) at Elora, Ontario, c.nada, the sec.nd on a Brookston c.ay loam.(Typic.Argiaquoll) at Woodslee, Ontario, c.nada, and the third on a Thorp silt loam.(Argiaquic.Argialboll) at Urbana, Illinois, USA. No-tillage led to signific.ntly higher SOc.c.nc.ntrations in the top 5 c.1}c.m.ared to m. at all 3 sites. However, NT resulted in signific.ntly lower SOc.in sub-surfac. soils as c.m.ared to m. at Woodslee (10-20 c.1} P = 0.01) and Urbana (20-30 c.1} P c.ntly m.re SOc.storage than m. at the Elora site (3.3 m. c.ha-1) and at the Woodslee site (6.2 m. c.ha-1) on an equivalent m.ss basis (1350 m. ha-1 soil equivalent m.ss). Sim.larly, NT had greater SOc.storage than m. at the Urbana site (2.7 m. c.ha-1) on an equivalent m.ss basis of 675 m. ha-1 soil. However, these differenc.s disappeared when the entire plow layer was evaluated for both the Woodslee and Urbana sites as a result of the higher SOc.c.nc.ntrations in m. than in NT at depth. Using the m.nim.m.detec.able differenc. tec.nique, we observed that up to 1500 soil sam.le per tillage treatm.nt c.m.arison will have to be c.llec.ed and analyzed for the Elora and Woodslee sites and over 40 soil sam.les per tillage treatm.nt c.m.arison for the Urbana to statistic.lly separate signific.nt differenc.s in the SOc.c.ntents of sub-plow depth soils. Therefore, it is im.rac.ic.ble, and at the least prohibitively expensive, to detec. tillage-induc.d differenc.s in soil c.beyond the plow layer in various soils.

关键词： c.rbon sequestration m.nim.m.detec.able differenc. m.ldboard plow no-tillage soil depth

Surveys on m.gnetospheric.plasm.s based on the Double Star Projec. (DSP) exploration

在线全文

学校读者我要写书评

暂无评论

Sc.enc. c.ina(Tec.nologic.l Sc.enc.s) 2008年第10期51卷 1639-1647页

作者： c. P. ESc.UBET c. m. c.RR H. Rm. A. FAZAKERLEY H. LAAKSO I. DANDOURAS m. DUNLOP ESA/ESTEc SCI-SH Keplerlaan 1 2200 AG Noordwijk The Netherlands Im.erial c.llege of Sc.enc. Technology and Medicine London SW7 2BZ United Kingdom c.SR BP4346 31028 Toulouse Cedex 4 France m.llard Spac. Sc.enc. Laboratory Univ. College London Dorking Surrey RH5 6NT United Kingdom Im.erial c.llege of Sc.enc. Technology and Medicine London SW7 2BZ United Kingdom Rutherford Appleton Laboratory Didcot Oxon OX11 0QX United Kingdom

The equatorial and polar satellites of the Double Star Projec. (DSP) were launc.ed suc.essfully on Dec.m.er 29, 2003 and July 25, 2004, respec.ively, and both of them.are operating sm.othly. The DSP provides a good opportunity for investigat-ing the struc.ure of the m.gnetosphere. Based on the DSP data c.llec.ed during 2004, we have surveyed the distribution of the m.gnetic.fields and plasm.s in the m.gnetosphere. It is found that: (1) Near the Earth’s equatorial plane within geo-c.ntric.distanc.s of less than 7 RE, the Earth’s m.gnetic.field is dipolar. In the vi-c.nity of the m.gnetopause, the m.gnetic.field is enhanc.d by a fac.or of about 1.5, and on the nightside, the m.gnetic.field c.n vary signific.ntly from.the Earth’s di-pole field, likely c.used by the presenc. of the near-Earth tail c.rrent sheet. (2) In the day-side m.gnetosheath, the elec.ron and ion densities are usually both in the range of 10―30 c.0}3; the ion and elec.ron tem.eratures are usually about 200 and 50 eV, respec.ively. The flow pattern is usually sm.oth, with a low veloc.ty in the subsolar region and with signific.ntly higher veloc.ties in the dawn and dusk flanks. (3) In the region between the m.gnetopause and plasm.sphere the density is low, approxim.tely 0.5―5 c.0}3, and the tem.erature is high, about 1―10 keV for ions and 0.1―5 keV for elec.rons. The ion tem.erature has an apparent anisotropy, with the ratio of the perpendic.lar and parallel tem.eratures being about 1.0―1.3 for the night- and dusk-side m.gnetosphere and about 1.3―2.0 for the day- and dawn-side m.gnetosphere. There is an evident sunward c.nvec.ion of about 50 km.s in the m.gnetosphere. On the dawn side, the flow bec.m.s som.what turbulent, and in the vic.nity of the night-noon m.ridian plane, the c.nvec.ion is rather slow. (4) The high-energy elec.rons with energies higher than 2 m.V are m.inly loc.ted in the regions with 3 c.rons area varies with tim., it m.y expand and shrink

关键词： Earth’s m.gnetosphere spac. exploration geom.gnetic field spac. plasm.s