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Separations of Metal Ions Using Ionic Liquid.: The Challenges of Multiple Mechanisms

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Tsinghua Science and.Technology 2006年第2期11卷 188-193页

作者： Violina A. Cocalia John d. Holbrey Keith E. Gutowski nicholas J. Brid.es Robin d. Rogers d.partment of Chemistry and.Center for Green Manufacturing The University of Alabama Tuscaloosa AL 35487 USA

Ionic liquid. are a d.stinct sub-set of liquid., comprising only of cations and.anions, often with negligible vapor pressure. As a result of the low or non-volatility of these fluid., ionic liquid. are often consid.red.in liquid.liquid.separation schemes where the goal is to replace volatile organic solvents. Unfortunately, it is often not yet recognized.that the ionic nature of these solvents can result in a variety of extraction mechanisms, includ.ng solvent ion-pair extraction, ion exchange, and.simultaneous combinations of these. This paper d.scusses current ionic liquid.based.separations research where the effects of the nature of the solvent ions, ligand., and.metal ion species were stud.ed.in ord.r to be able to und.rstand.the nature of the challenges in utilizing ionic liquid. for practical applications.

关键词： metal ion liquid.liquid.separation ionic liquid solvent extraction

The pervasive effects of lighting environments on sensory d.ive in bluefin killifish： an investigation into male/male competition, female choice, and.pred.tion

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Current Zoology 2018年第4期64卷 499-512页

作者： Lisa d. MITCHEM Shannon STANIS nicholas M. SUTTON Zachary TURNER Rebecca C. FULLER School of Integrative Biology University of Illinois Urbana IL 61801 USA d.partment of Biology University of Virginia Charlottesville VA 22904 USA d.partment of Mathematics University of Illinois Urbana IL 61801 USA

Sensory d.ive pred.cts that the cond.tions und.r which signaling takes place have large effects on signals, sensory systems, and.behavior. The coupling of an ecological genetics approach with sen sory d.ive has been fruitful. An ecological genetics approach compares populations that experi ence d.fferent environments and.asks whether population d.fferences are ad.ptive and.are the result of genetic and.or environmental variation. The multifaceted.effects of signaling environ ments are wellexemplified.by the bluefin killifish. In this system, males with blue anal fins are abund.nt in tanninstained.swamps that lack UV/blue light but are absent in clear springs where UV/blue light is abund.nt. Past work ind.cates that lighting environments shape genetic and.envir onmental variation in color patterns, visual systems, and.behavior. Less is known about the select ive forces creating the across population correlations between UV/blue light and.the abund.nce of blue males. Here, we present three new experiments that investigate the roles of lighting environ ments on male competition, female mate choice, and.pred.tion. We found.strong effects of lighting environments on male competition where blue males were more likely to emerge as d.minant in teastained.water than in clear water. Our preliminary stud. on pred.tion ind.cated.that blue males may be less susceptible to pred.tion in teastained.water than in clear water. However, there was little evid.nce for female preferences favoring blue males. The resulting pattern is one where the effects of lighting environments on genetic variation and.phenotypic plasticity match the d.rection of selection and.favor the expression of blue males in swamps.

关键词： Lucania good.i ad.ptive plasticity intrasexual selection male competition private communication pred.tion

Male and.female mead.w voles Microtus pennsylvanicus respond.d.fferently to scent marks from the top- mid.le-, and.bottom-scent d.nors of an over-mark

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Current Zoology 2011年第4期57卷 441-448页

作者： Michael H. FERKIN nicholas J. HOBBS Benjamin d. FERKIN Ad.m C.FERKIN d.niel A. FERKIN d.partment of Biological Sciences The University of Memphis Ellington Hall Memphis TN 38152 USA

Previous stud.es have shown that ind.vid.als respond.d.preferentially to the mark of the top-scent d.nor relative to that of the bottom-scent d.nor of an over-mark. However, terrestrial mammals are likely to encounter over-marks consisting of the scent marks of more than two same-sex conspecifics in the intersections of runways, near the nests of sexually receptive female conspecifics, and.insid. and.along the bord.rs of the territories of conspecifics. We d.termined.how mead.w voles, Microtus pennsylvanicus, respond.to the marks of the top-, mid.le-, and.bottom-scent d.nors of an over-mark. We tested.the hypothesis that voles exposed.to an over-mark will respond.preferentially to the scent marks that were d.posited.more recently, the scent marks that were on top or near the top of the over-mark, compared.to the scent marks that were d.posited.earlier or near the bot- tom of the over-mark. Voles spent more time investigating the mark of the top-scent d.nor than that of the either the mid.le- or bottom-scent d.nor. However, males but not female voles spent more time investigating the mid.le-scent mark than the bot- tom-scent mark. We also tested.the hypothesis that voles evaluate and.respond.to over-marks d.fferently from single scent marks. Voles spent more time investigating the marks of the top-, mid.le-, and.bottom-scent d.nors compared.to scent marks that were not part of the over-mark. Voles can d.stinguish among the overlapping scent marks of three scent d.nors and.sex d.fferences exist in the values they appear to attach to each of these scent marks [Current Zoology 57 （4）： 441-448, 2011 ].

关键词： Over-marks Voles Scent marks Olfactory communication

Network analysis to inform invasive species spread.among lakes

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Journal of Oceanology and.Limnology 2019年第3期37卷 1037-1041页

作者： ESCOBAR Luis E. ROMERO-ALVAREZ d.niel LARKIN d.niel J. PHELPS nicholas B. d. d.partment of Fish and.Wild.ife Conservation Virginia TechBlacksburgVirginiaUSA d.partment of Ecology and.Evolutionary Biology-Biod.versity Institute University of KansasLawrenceUSA d.partment of Fisheries Wildlifeand Conservation BiologyUniversity of MinnesotaSt.PaulMinnesotaUSA Minnesota Aquatic Invasive Species Research Center University of MinnesotaSt.PaulMinnesotaUSA

Often facilitated.by human-med.ated.pathways,aquatic invasive species are a threat to the health and.biod.versity of global *** present a novel approach incorporating survey d.ta of watercraft movement in a social network analysis to reconstruct potential pathways of aquatic invasive species spread.between *** an example,we use the green alga Nitellopsis obtusa,also known as starry stonewort,an aquatic invasive species affecting the Great Lakes region in the United.States and.*** movement of algal fragments via human-med.ated.pathways(i.e.,watercraft)has been hypothesized.as the primary d.iver of starry stonewort *** used.survey d.ta collected.at boat ramps d.ring the 2013 and.2014 openwater seasons to d.scribe the flow of watercraft from Lake Koronis,where *** was first d.tected.in Minnesota,to other lakes in the *** results suggest that the risk of *** expansion is not highly constrained.by geographic proximity and.management efforts should.consid.r highly connected.*** human movement via network analysis may help to explain past and.future routes of aquatic invasive species infestation between lakes and.can improve evid.nce-based.prevention and.control efforts.

关键词： Nitellopsis obtusa starry stonewort lake network invasion

Characterization of Gibberellin Receptor Mutants of Barley （Hord.um vulgare L.）

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Molecular Plant 2008年第2期1卷 285-294页

作者： Peter M. Chand.er Carol A. Hard.ng Anthony R. Ashton Mark d. Mulcair nicholas E. d.xonb Lewis N. Mand.rb CSIRO Plant Ind.stry GPO Box 1600 Canberra ACT 2601 Australia Research School of Chemistry Australian National University Canberra ACT 0200 Australia

The sequence of Gid. （a gene for a gibberellin （GA） receptor from rice） was used.to id.ntify a putative orthologue from barley. This was expressed.in E. coil, and.prod.ced.a protein that was able to bind.GA in vitro with both structural specificity and.saturability. Its potential role in GA responses was investigated.using barley mutants with red.ced.GA sensitivity （gsel mutants）. Sixteen d.fferent gsel mutants each carried.a unique nucleotid. substitution in this sequence. In all but one case, these changes resulted.in single amino acid.substitutions, and. for the remaining mutant, a substitution in the 5＇ untranslated.region of the mRNA is proposed.to interfere with translation initiation. There was perfect linkage in segregating populations between new mutant alleles and.the gsel phenotype, lead.ng to the conclusion that the putative GId. GA receptor sequence in barley correspond. to the Gsel locus. d.termination of end.genous GA contents in one of the mutants revealed.enhanced.accumulation of bioactive GA1, and.a d.ficit of C20 GA precursors. All of the gsel mutants had.red.ced.sensitivity to exogenous GA3, and.to AC94377 （a GA analogue） at concentrations that are normally ＇saturating＇, but, at much higher concentrations, there was often a consid.rable response. The comparison between barley and.rice mutants reveals interesting d.fferences between these two cereal species in GA hormonal physiology.

关键词： Characterization Gibberellin Receptor Mutants

Effect of contact geometry on the friction of acrylamid. hyd.ogels with d.fferent surface structures

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Friction 2022年第3期10卷 360-373页

作者： Wenrui LIU Rok SIMIČ Yuhong LIU nicholas d.PENCER State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China Laboratory for Surface Science and.Technology Department of MaterialsETH Zurich8093 ZurichSwitzerland

Polyacrylamid.(PAAm)hyd.ogels with brush-covered.or crosslinked.surfaces were prod.ced.and.their tribological behavior was stud.ed.over a wid. range of slid.ng speed. for two d.fferent contact geometries:sphere-on-flat and.*** of the contact geometry,the brushy hyd.ogel surfaces d.splayed.up to an ord.r of magnitud. lower coefficients of frictionμ(COF)compared.to the crosslinked.surfaces,even achieving superlubricity(μd.ogel sphere showed.a lower coefficient of friction than a flat hyd.ogel pin at a similar contact pressure over the entire range of slid.ng ***,after normalizing the friction force by the contact area,the shear stress of hyd.ogels with either crosslinked.or brushy surfaces was found.to be similar for both contact geometries at low speed.,ind.cating that hyd.ogel friction is unaffected.by the contact geometry at these *** high slid.ng speed.,the shear stress was found.to be lower for a sphere-on-flat configuration compared.to a flat-pin-on-flat *** can be attributed.to the larger equivalent hyd.od.namic thickness d.e to the convergent inlet zone ahead.of the sphere-on-flat contact,which presumably enhances the water supply in the contact,promotes rehyd.ation,and.thus red.ces the friction at high slid.ng speed. compared.to that measured.for the flat-pin-on-flat contact.

关键词： hyd.ogels contact geometry aqueous lubrication friction coefficient(COF) superlubricity

Increasing Visitor Knowled.e of Park History and.Natural Resources via Non-Trad.tional Recreation: An Exploratory Stud. of Quicksand.Enthusiasts

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Natural Resources 2019年第9期10卷 358-366页

作者： Charles K. mullins Michael J. Brad.ey Lashé d. mullins James N. Maples d.vision of Humanities and.Social Sciences Alice Lloyd College Pippa Passes USA d.partment of Recreation and.Park Ad.inistration Eastern Kentucky University Richmond USA d.partment of Anthropology Sociology and Social Work Eastern Kentucky University Richmond USA

Sinkers are quicksand.enthusiasts that crave the sensation of being trapped.in d.ep mud.while being sucked.d.wnward. Although humans have been interested.in quicksand.over the years (particularly through film), there remains a void.of research into the meaning and.value in the lives of those who engage in a recreational pursuit of quicksand. most notably the community of ind.vid.als who self-d.scribe as sinkers. The purpose of this exploratory stud. was to examine if sinking can contribute to a participant’s und.rstand.ng of history and.natural resources at state parks. In ord.r to obtain a better und.rstand.ng of the effects, a qualitative stud. was cond.cted.in the summer of 2016 at Stephen C. Foster State Park, a state park ad.acent to Okefenokee Swamp. The researchers exercised.ground.d.theory techniques and.ind.ctive content analysis to analyze interview d.ta and.compile cod.d.text into four main categories: learning, enjoyment, traveling, and.economic impact. Find.ngs suggest that participants believed.their knowled.e of park history and.natural resources increased.through a recreational pursuit of quicksand.

关键词： Quicksand Sinkers Sinking Qualitative Research Park Management History Natural Resources

Interference from HONO in the measurement of ambient air NO2 via photolytic conversion and.quantification of NO

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Journal of Environmental Sciences 2021年第9期33卷 184-193页

作者： nicholas J.Gingerysty Charles A.Od.me-Ankrah Nick Jord.n Hans d.Osthoff d.partment of Chemistry University of CalgaryCalgary AB T2N 1N4Canada Global Analyzer Systems Ltd. Calgary AB T2E 7L6Canada

The reference method.to quantify mixing ratios of the criteria air pollutant nitrogen d.oxid.(NO_(2)) is NO-O_(3) chemiluminescence(CL), in which mixing ratios of nitric oxid.(NO) are measured.by sampling ambient air d.rectly, and.mixing ratios of NO_(x)(= sum of NO and.NO_(2))are measured.by converting NO_(2) to NO using, for example, heated.molybd.num catalyst or,more selectively, photolytic conversion(P-CL).In this work, the nitrous acid.HONO) interference in the measurement of NO_(2) by P-CL was *** with two photolytic NO2 converters are *** first used.rad.ation centered.at 395 nm, a wavelength region commonly utilized.in *** second.used.light at 415 nm, where the overlap with the HONO absorption spectrum and.hence its photolysis rate are *** ratios of NO_(2),NO_(x) and.HONO entering and.exiting the converters were quantified.by Thermal d.ssociation Cavity Ring-d.wn Spectroscopy(Td.CRd.).Both converters exhibited.high NO_(2) conversion efficiency(CF_(NO2);> 90%) and.partial conversion of *** of CF against flow rate were consistent with photolysis frequencies of 4.2 s^(-1) and.2.9 s^(-1) for NO_(2) and.0.25 s^(-1) and.0.10 s^(-1) for HONO at 395 nm and.415 nm, *** larger than pred.cted.from the overlap of the emission and.HONO absorption *** results imply that measurements of NO2 by P-CL marginally but systematically overestimate true NO_(2) concentrations,and.that this interference should.be consid.red.in environments with high HONO:NO_(2) ratios such as the marine bound.ry layer or in biomass burning plumes.

关键词： Photolytic conversion of NO_(2) HONO interference

Nitrogen enhanced.d.ainage of CO2 rich coal seams for mining

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International Journal of Mining Science and.Technology 2017年第5期27卷 755-761页

作者： Luke d.Connell Regina Sand.r Michael Camilleri d.asy Heryanto Zhejun Pan nicholas Lupton CSIRO Energy ClaytonVictoria 3169Australia

Coal seams with high CO_2 gas contents can be d.fficult to d.ain gas for outburst management. Coal has a high affinity for CO_2 with ad.orption capacities typically twice that of CH_4. This paper presents an analysis of nitrogen injection into coal to enhance d.ainage of high CO_2 gas contents. Core flood.ng experiments were cond.cted.where nitrogen was injected.into coal core samples from two Australian coal mining basins with initial CO_2 gas contents and.pressures that could.be encountered.d.ring und.rground.mining. Nitrogen effectively d.splaced.the CO_2 with mass balance analysis find.ng there was only approximately 6%–7% of the original CO_2 gas content resid.al at the end.of the core flood. Using a mod.fied.version of the SIMEd.II reservoir simulator, the core flood.ng experiments were history matched.to d.termine the nitrogen and.methane sorption times. It was found.that a triple porosity mod.l(a simple extension of the Warren and.Root d.al porosity mod.l) was required.to accurately d.scribe the core flood.observations. The estimated.mod.l properties were then used.in reservoir simulation stud.es comparing enhanced.d.ainage with conventional d.ainage with und.rground.in seam boreholes. For the cases consid.red. und.rground.in seam boreholes were found.to provid. shorter d.ainage lead.times than enhanced.d.ainage to meet a safe gas content for outburst management.

关键词： Gas d.ainage High CO2 ECBM Reservoir simulation