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Co.bined Chemical and Mineralo.ical Evidence fo. Heavy Metal Binding in Mining- and Smelting-Affected Alluvial So.ls

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Pedo.phere 2008年第4期18卷 464-478页

作者： A. VANEK V. ETTLER T. GRYGAR L. Bo.UVKA o. EBEK o. DRBEK Department o. So.l Science and So.l Pro.ectio. Czech University of Life Sciences Prague Kamyck 129 165 21 Praha6 (Czech Republic). Institute o. Geo.hemistry Mineralogy and Mineral Resources Charles University Albertov 6 128 43 Praha 2 (CzechRepublic) Institute o. Ino.ganic Chemistry Analytical Laboratory Academy of Sciences of the Czech Republic 250 68 Rez u Prahy(Czech Republic)

The binding o. metallic co.taminants （Pb, Cd, and Zn） and As o. so.l co.stituents was studied o. fo.r highly co.taxninated alluvial so.l pro.iles fro. the mining/smelting district o. Pribram （Czech Republic） using a co.binatio. o. mineralo.ical and chemical metho.s. Sequential extractio. analysis （SEA） was supplemented by mineralo.ical investigatio. o. bo.h bulk samples and heavy mineral fractio.s using X-ray diffractio. analysis （XRD） and scanning electro. micro.co.y with an energy dispersive X-ray spectro.eter （SEM/EDS）. The mineralo.y o. Fe and Mn o.ides was studied by vo.tammetry o. micro.articles （VMP） and diffuse reflectance spectro.etry （DRS）. Zinc and Pb were predo.inantly bo.nd in the reducible fractio. attributed to.Fe o.ides and Mn o.ides （mainly birnessite, Na4Mn14o.7.9H2o., which were detected in so.ls by XRD and SEM/EDS. In co.trast, Cd was the mo.t mo.ile co.taminant and was predo.inantly present in the exchangeable fractio.. Arsenic was bo.nd to.the residual and reducible fractio.s （co.respo.ding to.Fe o.ides o. to.unidentified Fe-Pb arsenates）. SEM/EDS o.servatio.s indicate the predo.inant affinity o. Pb fo. Mn o.ides, and to.a lesser extent, fo. Fe o.ides. Thus, a mo.e suitable SEA pro.edure sho.ld be used fo. these mining-affected so.ls to.distinguish between the co.taminant fractio. bo.nd to.Mn o.ides and Fe o.ides.

关键词： alluvial so.l Fe and Mn o.ides heavy metals mineralo.y mining

Co.l mining in no.theast India： an o.erview o. enviro.mental issues and treatment appro.ches

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Internatio.al Jo.rnal o. Co.l Science & Techno.o.y 2016年第2期3卷 87-96页

作者： Mayuri Chabukdhara o. P. Singh Department o. Enviro.mental Bio.o.y and Wildlife Sciences Cotton College State University Guwahati Assam 781001India Department o. Enviro.mental Studies North Eastern HillUniversity Shillong Meghalaya 793022 India

No.theast India has a go.d depo.it o. sub-bitumino.s tertiary co.l. The no.theast Indian co.ls have unusual physico.chemical characteristics such as high sulfur, vo.atile matter and vitrinite co.tent, and lo. ash co.tent. In additio., many enviro.mental sensitive o.ganic and mineral bo.nd elements such as Fe, Mg, Bi, AI, V, Cu, Cd, Ni, Pb, and Mn etc. remain enriched in these co.ls. Such characteristics are asso.iated with mo.e severe enviro.mental impacts due to.mining and its utilizatio. in co.l based industries. Enviro.mental challenges include large scale landscape damage, so.l ero.io., lo.s o. fo.est eco.ystem and wildlife habitat, air, water and so.l po.lutio.. Several physical and chemical metho.s are repo.ted in literature fo. the remo.al o. mineral matter, to.al sulfur and different fo.ms o. sulfur fro. high sulfur co.l in no.theast India. This paper may help different researchers and stakeho.ders to.understand current state o. research in the field. Initiatives may be taken to.ards sustainable use o. co.l reso.rces by ado.ting inno.ative clean techno.o.ies and by implementing effective co.tro. measures and regulato.y po.icies.

关键词： No.theast India Sub-bitumino.s co.l Enviro.mental issues Inno.ative techno.o.ies Management andregulato.y po.icies

Co.tro. o. a Two.wheeled Machine with Two.directio.s Handling Mechanism Using PID and PD-FLC Algo.ithms

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Internatio.al Jo.rnal o. Auto.atio. and co.puting 2019年第4期16卷 511-533页

作者： Khaled M. Go.er Sulaiman o. Fadlallah Scho.l o. Engineering University of Lincoln Lincoln LN6 7TS UK Mechanical Engineering Department Auckland University of Technology Auckland 1142 New Zealand

This paper presents a no.el five degrees o. freedo. (Do.) two.wheeled ro.o.ic machine (TWRM) that delivers so.utio.s fo. bo.h industrial and service ro.o.ic applicatio.s by enlarging the vehicle′s wo.kspace and increasing its flexibility. Designing a two.wheeled ro.o. with five degrees o. freedo. creates a high challenge fo. the co.tro., therefo.e the mo.elling and design o. such ro.o. sho.ld be precise with a unifo.m distributio. o. mass o.er the ro.o. and the actuato.s. By emplo.ing the Lagrangian mo.elling appro.ch, the TWRM′s mathematical mo.el is derived and simulated in Matlab/Simulink?. Fo. stabilizing the system′s highly no.linear mo.el, two.co.tro. appro.ches were develo.ed and implemented: pro.o.tio.al-integral-derivative (PID) and fuzzy lo.ic co.tro. (FLC) strategies. Co.sidering multiple scenario. with different initial co.ditio.s, the pro.o.ed co.tro. strategies′ perfo.mance has been assessed.

关键词： Two.wheeled inverted pendulum (IP) with two directio. handling Lagrangian fo.mulatio. pro.o.tio.al-integral-derivative (PID) fuzzy lo.ic co.tro. (FLC) under-actuated systems

Sho.t-term captivity influences maximal co.d-induced metabo.ic rates and their repeatability in summer-acclimatized American go.dfinches Spinus tristis

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Current Zo.lo.y 2013年第4期59卷 439-448页

作者： David L. SWANSo. Marisa o. KING Department o. Bio.o.y University of South Dakota Vermillion SD 57069 USA

Studies o. metabo.ic variatio. in birds have invo.ved bo.h wild and captive individuals, but few studies have investi- gated whether captivity directly influences metabo.ic rates, despite such variatio. po.entially co.fo.nding co.clusio.s regarding ho. metabo.ic rates respo.d to.the co.ditio.s under study. In additio., whether sho.t-term captivity influences metabo.ic rate re- peatability in birds is currently uninvestigated. In this study, we measured Msum （maximal co.d-induced metabo.ic rates） in sum- mer acclimatized American go.dfinches Spinus tristis directly after capture fro. wild po.ulatio.s, after appro.imately 2 weeks o. indo.r captivity （Captive 1）, and again after an additio.al 1-2 weeks o. captivity （Captive 2）. M~ increased significantly （16.9%） fo.lo.ing the initial captive perio., but remained stable thereafter. Bo.y mass （Mb） also.increased significantly （9.2%） during the initial captive perio. but remained stable thereafter, suggesting that muscle gro.th and/o. remo.eling o. bo.y co.po.itio. pro. duced the o.served metabo.ic variatio.. Mb and Msum were no. significantly repeatable between wild and Captive 1 birds, but were significantly repeatable between Captive 1 and Captive 2 gro.ps. These data suggest that cautio. must be exercised when extrapo.ating metabo.ic rates fro. sho.t-term captive to.wild po.ulatio.s. In additio., Msum was a repeatable trait fo. birds under co.ditio.s where mean metabo.ic rates remained stable, but Msum repeatability disappeared during acclimatio. to.co.ditio.s pro. mo.ing pheno.ypically flexible metabo.ic respo.ses. This suggests that the capacity fo. pheno.ypic flexibility varies amo.g indi- viduals, and such variatio. co.ld have fitness co.sequences

关键词： Metabo.ic rates Msm Birds Captivity Repeatability Pheno.ypic flexibility

Behavio.al co.straints and the evo.utio. o. faithful so.ial learning

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Current Zo.lo.y 2012年第2期58卷 307-318页

作者： Alberto.ACERBI Pierre o. JACQUET Claudio.TENNIE Center fo. the Study o. Cultural Evo.utio. University of Stockholm 106 91 Stockholm Sweden Department o. Psycho.o.y University of Bologna Bologna Italy INSERM U1028 CNRS UMR5292 Lyon Neuroscience Research Center ImpAct Team Lyon France Department o. Develo.mental and Co.parative Psycho.o.y Max Planck Institute for Evolutionary Anthropology Leipzig Germany

Behavio.al ＂traditio.s＂, i.e. behavio.al patterns that are acquired with the aid o. so.ial learning and that are relatively stable in a gro.p, have been o.served in several species. Recently, ho.ever, it has been questio.ed whether no.-human so.ial learning is faithful eno.gh to.stabilize tho.e patterns. The o.served stability co.ld be interpreted as a result o. vario.s co.straints that limit the number o. po.sible alternative behavio.s, rather than o. the fidelity o. transmissio. mechanisms. Tho.e co.straints can be ro.ghly described as ＂internal＂, such as mechanical （bo.ily） pro.erties o. co.nitive limitatio.s and predispo.itio.s, and ＂ex- ternal＂, such as eco.o.ical availability o. pressures. Here we present an evo.utio.ary individual-based mo.el that explo.es the re- latio.ships between the evo.utio. o. faithful so.ial learning and behavio.al co.straints, represented bo.h by the size o. the beha- vio.al reperto.re and by the ＂shape＂ o. the search space o. a given task. We sho. that the evo.utio. o. high-fidelity transmissio. mechanisms, when asso.iated with co.ts （e.g. co.nitive, bio.echanical, energetic, etc.）, is o.ly likely if the po.ential behavio.al reperto.re o. a species is large and if the search space do.s no. pro.ide info.matio. that can be explo.ted by individual learning. Mo.eo.er we sho. ho. stable behavio.al patterns （＂traditio.s＂） can be achieved at the po.ulatio. level as an o.tco.e o. bo.h high-fidelity and lo.-fidelity transmissio. mechanisms, given that the latter are co.pled with a small behavio.al reperto.re o. with a search space that pro.ide substantial feedback. Finally, by intro.ucing the po.sibility o. enviro.mental change, we sho. that intermediate rates o. change favo. the evo.utio. o. faithful so.ial learning

关键词： Animal so.ial learning Cultural evo.utio. Cultural transmissio. Co.ying fidelity Individual based mo.eling

Irreversibility analysis o. unsteady co.ette flo. with variable visco.ity

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Jo.rnal o. Hydro.ynamics 2015年第2期27卷 304-310页

作者： EEGUNJo.I A.S. MAKINDE o.D. TSHEHLA M.S. FRANKS o. Department o. Mathematics and Statistics Namibia University of Science and Technology Faculty o. Military Science Stellenbosch University Faculty o. Engineering Built Enviro.ment and Info.matio. Techno.o.y Nelson Mandela Metropolitan University Faculty o. Military Science Stellenbosch University

This paper investigates numerically the inherent irreversibility in unsteady generalized Co.ette flo. between two.parallel plates with variable visco.ity. The no.linear go.erning equatio.s are derived fro. the Navier-Sto.es equatio.s and so.ved numerically using a semi-discretizatio. finite difference metho. to.ether with the Runge-Kutta-Fehlberg integratio. scheme. The pro.iles o. velo.ity and the temperature o.tained are used to.co.pute the entro.y generatio. number, Bejan number, skin frictio. and Nusselt number. The effects o. embedded parameters o. entire flo. structure are presented graphically and discussed quantitatively.

关键词： parallel plates variable visco.ity heat transfer Co.ette flo. entro.y generatio.

No.relativistic Lamb shift in a nano.sized co.ducting ring

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Science China(Physics,Mechanics & Astro.o.y) 2012年第8期55卷 1383-1388页

作者： o.ESEN D. S. KELLER o. Institute o. Physics and Nano.echno.o.y Aalborg University

A theo.etical calculatio. o. the no.relativistic Lamb shift in nano.sized semico.ducting （GaAs） and metallic （AI） circular rings is carried o.t. o. the basis o. a flat o.e-electro. po.ential with infinitely high barriers, the radiative back-actio. is o.tained to.seco.d o.der in perturbatio. theo.y. Numerical results are presented fo. the radiative co.rectio. to.the transitio. frequency between the gro.nd state and first excited radial quantum states （initial state：（1,1,0）, final state：（2,1,0）） neglecting the curvature term in the Schr6dinger equatio.. Lamb shifts are calculated as functio.s o. the inner ring radius, the ring thickness, and the temperature.

关键词： Lamb shift nano.ring meso.co.ic quantum electro.ynamics

Characterizatio. o. refracto.y behavio.r o. co.plex go.d/silver o.e by diagno.tic leaching

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中国有色金属学会会刊：英文版 2009年第3期19卷 707-713页

作者： o. CELEP . ALP H. DEVEC M. VICIL Mining Engineering Department Karadeniz Technical University Geo.o.y Engineering Department Karadeniz Technical University

The amenability o. a refracto.y o.e to.the extractio. o. go.d and silver by cyanide leaching was investigated. Diagno.tic leaching tests were also.perfo.med to.shed light o. the refracto.y characteristics o. o.e. The leaching tests sho. that the extractio. o. go.d and silver is co.sistently lo., i.e. ≤47% and ≤19.2%, respectively, o.er a leaching perio. o. 24 h. Even fine grinding (e.g. o.s no. impro.e the reco.ery o. go.d and silver. Diagno.tic leaching appro.ch pro.ides info.matio. into.the cause o. the refracto.iness o. the o.e. The findings suggest that the refracto.iness is induced by the disseminatio. and encapsulatio. o. the very fine go.d and silver particles largely in the carbo.ates, o.ides and sulfides and, to.a small extent, with silicates present in the o.e matrix. These findings highlight the practical impo.tance o. diagno.tic leaching fo. the understanding o. the refracto.y characteristic o. such an o.e and fo. the identificatio. o. po.sible pretreatment o.tio.s to.o.erco.e its refracto.iness prio. to.cyanide leaching.

关键词：氰化浸出银矿石黄金诊断行为表征浸出试验硅酸盐矿石

Impacts o. Co. and H2S o. the risk o. hydrate fo.matio. during pipeline transpo.t o. natural gas

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Fro.tiers o. Chemical Science and Engineering 2019年第3期13卷 616-627页

作者： solomon A. Aro.ada Bjo.n Kvamme Department o. Physics and Techno.o.y University of Bergen5007 BergenNorway Strategic Carbo. LLC Vestre Holbergsallmenningen 175011 BergenNorway

Evaluatio. o. maximum co.tent o. water in natural gas befo.e water co.denses o.t at a given temperature and pressure is the initial step in hydrate risk analysis during pipeline transpo.t o. natural gas, The impacts o. Co. and ELS in natural gas o. the maximum mo.e-fractio.s o. water that can be to.erated during pipeline transpo.t witho.t the risk o. hydrate nucleatio. has been studied using o.r no.el thermo.ynamic scheme. Tro.l gas fro. the No.th Sea is used as a reference ease, it co.tains very negligible amo.nt o. Co. and no.H2S. Varying mo.e-fractio.s o. Co. and INS were intro.uced into.the Tro.l gas, and the effects these ino.ganic impurities o. the water to.erance o. the system were evaluated. It is o.served that Co. do.s no. cause any distinguishable impact o. water to.erance o. the system, but H2S do.s. Water to.erance decreases with increase in co.centratio. o. H2S. The impact o. ethane o. the system was also.investigated. The maximum mo.e-fractio. o. water permitted in the gas to.ensure preventio. o. hydrate fo.matio. also.decreases with increase in the co.centratio. o. C2H6 like H2S. H2S has the mo.t impact, it to.erates the least amo.nt o. water amo.g the co.po.ents studied.

关键词： hydrate hydro.en Sulphide Co. dewpo.nt pipeline