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北极岩石圈综述

海洋地质 2015年第2期31卷 52-81页

作者： V. Pease S. Dr.chev r. stephenson 祝嵩李学杰杨丽娟范广慧不详广州海洋地质调查局海洋区域地质调查所 510760

本文综述了北极地区岩石圈的性质及主要构造事件。当前对地壳、地壳尺度的不整合及其年龄的认识，以及通过地球物理数据对岩石圈的认识，可以对北极岩石圈进行分区。北极大陆岩石圈的年龄、成分和结构不同，至少受两期大规模岩浆作用的... 详细信息

本文综述了北极地区岩石圈的性质及主要构造事件。当前对地壳、地壳尺度的不整合及其年龄的认识，以及通过地球物理数据对岩石圈的认识，可以对北极岩石圈进行分区。北极大陆岩石圈的年龄、成分和结构不同，至少受两期大规模岩浆作用的叠加影响，一次是二叠纪-三叠纪，另一次是阿普特期。此外，大陆岩石圈的减薄至少是五期裂谷作用的结果（晚泥盆世-早石炭世、二叠纪-三叠纪、侏罗纪、早白垩世、晚白垩世-新生代）。老阶段的拼合与大陆岩石圈和古生代一系列陆陆碰撞有关。侏罗纪和白垩纪伸展阶段与泛大陆和欧亚大陆的裂解有关，并且主要集中在挪威-格陵兰和加拿大-阿拉斯加北极地区。美亚海盆发育大面积超伸展大陆（？）岩石圈。在大陆解体和新大洋岩石圈增生后，欧亚海盆和加拿大海盆形成。

关键词：北极陆壳岩石圈洋壳岩石圈构造

E-Tender.ng Pr.cess Within Constr.ction:A UK Per.pective

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Tsinghua Science and Technology 2008年第S1期13卷 273-278页

作者： Geoff Tindsley Paul stephenson Division of Built Envir.nment Faculty of Development and Society Sheffield Hallam University

E-tender.ng can be defined as the issue and r.ceipt of tender.documentation thr.ugh electr.nic means which facilitates the pr.cur.ment of constr.ction wor. and the awar. of contr.cts. The cur.ent paper.based method of tender.ng has been commonplace within the industr. for.a significant number.of year., but with r.cent technological advancements, this tr.ditional pr.cess is r.pidly becoming outdated. Sever.l major.pr.jects within the UK ar. now being pr.cur.d thr.ugh the e-tender.ng pr.cess which includes the multibillion pound development for.the Olympic Games in London 2012. However. while these pr.stigious pr.jects ar. embr.cing e-tender.ng technology, it is not cer.ain as to what extent e-tender.ng is used acr.ss the constr.ction sector.gener.lly. This r.sear.h is pr.mar.ly concer.ed with establishing the cur.ent status, pr.cticalities and r.sour.e effectiveness of e-tender.ng within UK constr.ction. r.sults ar. pr.vided fr.m an in-dustr. sur.ey which includes both quantitative and qualitative data. A case study implementation is also in-cluded which assesses the utilisation of e-tender.ng softwar. in pr.ctice. The r.sear.h findings indicated that e-tender.ng can pr.vide substantial r.sour.e savings to a major.par. of the supply chain, with the key benefits being enhanced communication, time savings and r.duced costs. However. a consider.ble pr.por.ion of the industr. r.mains uncer.ain about embr.cing new technologies, with r.luctance to change being per.eived as the gr.atest bar.ier. The findings suggest that many pr.fessionals within the UK constr.ction industr. r.cognise a r.quir.ment for.incr.ased implementation of e-tender.ng, but feel that tr.ining, education and suppor. fr.m senior.management ar. essential r.quir.ments for.e-tender.ng to become widely accepted in the futur..

关键词： constr.ction pr.ject data electr.nic communications e-tender.ng

Development of a br.wnfield inventor. for.pr.or.tizing funding outr.ach in Tucson,Ar.zona

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Geo-Spatial Infor.ation Science 2021年第4期24卷 742-754页

作者： Ther.sa Foley Ann Mar.e Wolf Chloe Jackson r.an stephenson Sonor. Envir.nmental r.sear.h Institute Inc.(SERI)TucsonAZUSA Pima County ITD/GIS TucsonAZUSA Pima County Community Development&Neighbor.ood Conser.ation TucsonAZUS

Fear.of liability fr.m the 1980 Compr.hensive Envir.nmental r.sponse,Compensation,and Liability Act(CEr.LA or.Super.und)has pr.mpted developer. to build pr.fer.ntially upon undeveloped gr.en space r.ther.than potentially contaminated for.er.industr.al sites,leading to ur.an spr.wl in the subur.an ar.as while blighted pr.per.ies in the ur.an cor. r.main vacant.A br.wnfield is defined as a pr.per.y in which the pr.sence or.potential pr.sence of a hazar.ous substance or.contaminant poses a bar.ier.to *** often cr.ate br.wnfield inventor.es by per.or.ing a site suitability analysis,using distinguishing featur.s such as ecolo-gically and cultur.lly significant ar.as or.neighbor.oods that need *** County,Ar.zona and the Sonor. Envir.nmental r.sear.h Institute,Inc.(SEr.)developed a br.wnfield inventor. of the lar.e,industr.al ar.a dir.ctly to the west of Davis-Monthan Air.For.e *** the br.wnfield tar.et ar.a has few r.sidential neighbor.oods and lacks the distinguish-ing featur.s usually used in a br.wnfield site suitability analysis,the county and SEr. used the official tax assessor.database and 11 feder.l,state and county envir.nmental databases to develop a br.wnfield *** goal of the pr.ject was to pr.or.tize pr.per.ies that stood to benefit fr.m the gr.nt *** final br.wnfield inventor. contained 531 par.els.

关键词： GIS site suitability analysis br.wnfield ur.an planning br.wnfield inventor.

Effect of for.st distur.ance on myxomycete assemblages in the southwester. Per.vian Amazon

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Fungal Diver.ity 2013年第2期59卷 45-53页

作者： Car.os r.jas Steven L.stephenson Instituto de Investigaciones en Ingenier.a and Escuela de Biología Universidad de Costa RicaSan Pedro de Montes de Oca 11501-2060Costa Rica Depar.ment of Biological Sciences University of ArkansasFayettevilleAR 72701-1201USA

Although the effects of micr.envir.nmental factor. on distr.bution patter.s in myxomycetes have been investigated,studies of the r.sponses of this gr.up of or.anisms to differ.nt r.gimes of for.st distur.ance ar. r.latively few in *** an effor. to under.tand the implications of for.st fr.gmentation and habitat loss on myxomycetes,the pr.ject descr.bed her.in was car.ied out at the Los Amigos Biological Station in southeaster. *** str.ctur. and composition of assemblages of myxomycetes wer. investigated in r.lation to thr.e differ.nt for.st types and climatic per.ods in the ar.a of *** analysis of the most commonly r.cor.ed substr.tes was car.ied out as *** r.sults suggested that habitat loss,thr.ugh differ.nces in for.st str.ctur.,was the factor.deter.ining most of the differ.nces in fr.iting body abundance of myxomycetes among for.st *** addition,a switch in the ecological str.tegy of disper.al seemed to be an impor.ant factor.accounting for.differ.nces in the fr.iting body abundance and str.ctur. of assemblages of myxomycetes between collecting *** study pr.vides evidence indicating that for.micr.bial assemblages to maintain the balance of functional inter.ctions within a par.icular.for.st ecosystem,the conser.ation of the for.sts themselves should be consider.d.

关键词： Biogeogr.phy Micr.bial ecology Mycetozoans Myxogastr.ds r.stor.tion ecology

The r.le of Ca,Al and Zn on r.om temper.tur. ductility and gr.in boundar. cohesion of magnesium

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Jour.al of Magnesium and Alloys 2021年第5期9卷 1536-1551页

作者： Supr.ya Nandy Shao-Pu Tsai Leigh stephenson Dier. r.abe Stefan Zaeffer.r Max-Planck Institut für.Eisenfor.chung Düsseldorf 40237Germany

It is know fr.m liter.tur. that small additions(<1 wt%)of Ca,Al and Zn significantly impr.ve the intr.nsic ductility of *** exact r.le of each element,both qualitatively and quantitatively,and their.combined effects,h... 详细信息

It is know fr.m liter.tur. that small additions(r.ve the intr.nsic ductility of *** exact r.le of each element,both qualitatively and quantitatively,and their.combined effects,however.ar. poor.y *** we achieved a much clear.r.view on the quantitative r.le of each element with r.spect to ductility impr.vement and on the collabor.tive effect,par.icular.y of Ca and Zn in *** of our.findings and conclusions ar. in disagr.ement with data and inter.r.tation found in *** differ.nt alloys,namely,Mg-0.1 Ca,Mg-0.1 Ca-1 Al,Mg-0.05 Ca-1 Al,Mg-0.1 Ca-2 Al-1 Zn(all ar. in wt%)wer. selected for.this *** alloys wer. tr.ated such that *** gr.in sizes and textur.s wer. *** lar.ely excludes the effect of extr.nsic factor. on ***-guided slip tr.ce analyses r.veal that the addition of Ca eases activation of pr.smatic and pyr.midal II slip *** in-situ defor.ation exper.ments in SEM and atom pr.be tomogr.phy obser.ations of gr.in boundar.es dir.ct evidence is given for.the individual and syner.etic effects of Ca and Zn on gr.in boundar. cohesion as an impor.ant contr.bution to impr.ve the ductility of these *** conclude that Ca r.duces the slip anisotr.py and amelior.tes ductility,however.the weak gr.in boundar. cohesion in the Mg-0.1 wt%Ca alloy limits the mater.al’s tensile *** addition of Zn alter. the Ca segr.gation at the gr.in boundar.es and helps to r.tain their.cohesive str.ngth,an effect which thus enables higher.ductility and *** fur.her.addition of Al pr.mar.ly impr.ves the *** r.sults show that the balanced influence of r.duced slip anisotr.py on the one hand and incr.ased gr.in boundar. cohesion on the other.hand allow to design a high str.ngth high ductility r.r.-ear.h fr.e Mg alloy.

关键词： Magnesium–Calcium–Zinc alloys Ductility Slip system deter.ination gr.in boundar. cohesion

Myxomycetes associated with gr.sslands of the wester. centr.l United States

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Fungal Diver.ity 2013年第2期59卷 147-158页

作者： Adam W.r.llins Steven L.stephenson Depar.ment of Biology Lincoln Memorial UniversityHarrogateTN 37752USA Depar.ment of Biological Sciences University of ArkansasFayettevilleAR 72701USA

The assemblages of myxomycetes associated with the thr.e types of temper.te gr.sslands(tall gr.ss,mixed gr.ss and shor. gr.ss)found acr.ss the wester. centr.l United States wer. examined by collecting samples for.isolation of these or.anisms fr.m nine study *** consisted of two types of gr.und litter.two types of aer.al litter.dead but still attached plant par.s)and *** wer. br.ught back to the labor.tor. and used to pr.par. a ser.es of moist chamber.*** cultur.s yielded 1,301 collections of myxomycetes r.pr.senting 59 species in 18 *** collections could be identified only to genus and one in par.icular.Lepidoder.a sp.)appear. to be an undescr.bed *** spectabile was r.cor.ed for.the fir.t time in Nor.h ***,only eight species(Badhamia melanospor.,Didymium anellus,***,***,Per.chaena depr.ssa,Physar.m ciner.um,***,and Stemonitis fusca)wer. r.cover.d fr.m all nine study sites and thus ar. consider.d to r.pr.sent a cor. component of the myxomycete biota of temper.te gr.sslands.

关键词： Community ecology Ecological distr.bution Gr.sslands Micr.habitat Myxogastr.ds

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The Ser.ent Column

The Serpent Column

A Sur.ey of Genetic Diver.ity of the Weedy Species <i>Ipomoea lacunosa</i>L. in the USA Mid-South

作者： stephenson Paul

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Amer.can Jour.al of Plant Sciences 2011年第3期2卷 396-407页

作者： Nilda r. Bur.os Daniel O. stephenson Hesham A. Agr.ma Lawr.nce r. Oliver.Jason A. Bond 不详

Mor.ingglor.es (Ipomoea spp.) ar. among the most tr.ublesome weedy species in agr.ecological envir.nments. Ipomoea lacunosa is one of the most pr.valent of these species. Localized adaptations r.sulted in the evolution of sever.l I. lacunosa ecotypes in Nor.h Amer.ca, which could potentially impact its r.sponse to cr.p management pr.ctices. To evaluate the genetic diver.ity and population str.ctur. of I. lacunosa populations, we amplified inter.simple sequence r.peats loci by polymer.se chain r.action (ISSr.PCr. of 64 accessions using 14 ISSr.pr.mer. for.Ipomoea. Of these, 64 polymor.hic fr.gments wer. scor.d. Analysis of Nei’s genetic distance (GD) values placed the accessions into four.genotypic cluster., two of which wer. composed pr.mar.ly of accessions fr.m Ar.ansas and Mississippi with GD between cluster. of 0.318. The over.ll GD was 0.238, indicating a nar.ow genetic base. Population str.ctur. analysis deter.ined thr.e ancestr.l subgr.ups, with the major.ty of Ar.ansas and Mississippi accessions separ.ted into two subgr.ups. The existence of var.ous genotypes and ecotypes of I. lacunosa demonstr.tes the evolutionar. diver.ification of this weedy species as it adapts to new colonized envir.nments and agr.cultur.l activities.

关键词： DNA Finger.r.nting Genetic Diver.ity Ipomoea ISSr Mor.ingglor. Species Mor.ingglor. Genotypes Population Str.ctur.

Myxomycete colonization on tr.nslocated and non-tr.nslocated dead leaves fr.m temper.te and tr.pical for.sts

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Studies in Fungi 2020年第1期5卷 462-470页

作者： r.jas C stephenson SL r.jas PA Finca Exper.mental Inter.isciplinar.a de Modelos Agr.ecológicos University of Costa RicaTurrialba30502-Costa Rica Engineer.ng r.sear.h Institute University of Costa RicaSan Pedro de Montes de Oca11501-Costa Rica Depar.ment of Biological Sciences University of ArkansasFayettevilleAR 72701USA

Samples of dead leaves on the for.st floor.wer. collected fr.m a locality in centr.l Costa r.ca and another.locality in nor.hwest Ar.ansas in the United States and then wer. placed in fine-mesh nylon bags,autoclaved and left out in the field for.four.*** of the bags pr.par.d with ster.le mater.al fr.m each countr. wer. placed out in the countr. wher. they wer. collected,and the other.half wer. placed in the other.countr..A char.cter.zation of for.st str.ctur. and gr.und leaf chemistr. was car.ied out for.both localities and both leaf *** r.collected,all samples wer. pr.cessed for.myxomycetes with the use of the moist chamber.cultur. *** cultur.s yielded a total of 156 r.cor.s of myxomycetes r.pr.senting 16 species,but only 13 r.cor.s and six species wer. isolated fr.m the samples left out in Costa *** hundr.d per.ent of cultur.s placed out in Ar.ansas pr.duced myxomycetes,wher.as only 68%of those placed out in Costa r.ca wer. positive for.these *** in species r.chness and number.of r.cor.s wer. obser.ed acr.ss for.sts wher. the samples wer. placed out,and no differ.nces wer. obser.ed based on the or.gin of the *** suggested that myxomycete colonization in the studied ar.as is pr.mar.ly affected by the dynamics of the for.st type and secondar.ly by substr.te *** myxomycete species r.cor.ed on leaves with poor.r.chemical values ar. also consistent with field *** the pr.sent study,the mor. open char.cter.of the temper.te for.st in Ar.ansas without a film of water.layer.cover.ng the leaves on the gr.und seemed to have played a r.le in the establishment of myxomycete pr.pagules in the ster.le mater.al dur.ng the time of the investigation.

关键词： Ar.ansas Costa r.ca myxogastr.ds Pea r.dge slime molds Tur.ialba