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On the Lim.ts to m.nage Air-Quality in Glacier Bay

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Journal of Environm.ntal Protection 2016年第12期7卷 1923-1955页

作者： Nicole m.lders scott gende Departm.nt of Atm.spheric Sciences Geophysical Institute College of Natural Science University of Alaska Fairbanks Fairbanks AK USA National Park Service Juneau AK USA

In Glacier Bay National Park, about 95% of the visitors com. on board of cruise ships. The National Park Service has the m.ndate to m.nage park resources like air quality and visibility, while ensuring visitation. To understand the im.act of cruise-ship em.ssions on the overall concentrations in Glacier Bay, em.ssion-source contribution ratios (ESCR) and the interaction of pollutant from.local and/or distant sources were determ.ned using results from.four WRF/Chem.sim.lations of the 2008 tourist season (m.y 15 to Septem.er 15). These sim.lations only differed by the em.ssions considered: Biogenic em.ssions only (CLN), biogenic plus activity-based cruise-ship em.ssions (REF), biogenic plus all anthropogenic em.ssions except cruise-ship em.ssions (RETRO), and all aforem.ntioned em.ssions (ALL). In general, ESCRs differed am.ng pollutants. Interaction between pollutants from.cruise-ship em.ssions and species from.other sources including those advected into the bay decreased towards the top of the atm.spheric boundary layer. Pollutants from.different sources interacted strongest (lowest) in the west arm.of the fjord where ships berthed for glacier viewing (in areas of the bay without cruise-ship travel). Pollutant interaction both enhanced/reduced NO2 concentrations by 10% (4 - 8 ppt absolute). Except for ozone, cruise-ship em.ssions on average governed air quality in the bay. On days with cruise-ship visits, they contributed between 60% and 80% of the bay-wide daily m.an SO2 and NO2 concentrations below 1 km.height. On days without visits, cruise-ship contributions still reached 40% due to previous visits. Highest cruise-ship ESCRs occurred during stagnant weather conditions. Despite the fact that all coarse particulate m.tter was due to anthropogenic sources, worst visibility conditions were due to m.teorology. The results suggest lim.ts as well as windows for m.naging air quality and visibility in Glacier Bay.

关键词： Glacier Bay National Park Em.ssion-Source Contribution Cruise-Ship Em.ssions Air-Quality m.nagem.nt Interaction of Pollutants

Im.acts of Cruise-Ship Entry Quotas on Visibility and Air Quality in Glacier Bay

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Journal of Environm.ntal Protection 2015年第11期6卷 1236-1256页

作者： Nicole m.lders scott gende Departm.nt of Atm.spheric Sciences Geophysical Institute and College of Natural Science and MathematicsUniversity of Alaska FairbanksFairbanksAKUSA Glacier Bay Field Station National Park ServiceJuneauAKUSA

m.nagers at Glacier Bay National Park m.st annually determ.ne the allowable num.er of cruise-ship entries into the park. This decision considers how differences in visitor volum. m.y affect park resources. This study quantified the im.acts to air quality and visibility under different ship quotas using sim.lations with the Weather Research and Forecasting m.del inline coupled with chem.stry. Results of the sim.lation assum.ng two entries per day for m.y 15 to Septem.er 15, 2008 (QTA;248 ship entries representing a 35% increase) were com.ared to those of the 2008 cruise-ship activity (REF;184) during that tim.fram.. A sim.lation without anthropogenic em.ssions (CLN) served to assess the overall im.acts of cruise-ship em.ssions on visibility and air quality in Glacier Bay. Com.ared to REF, the increased entry quotas shifted chem.cal regim.s and aerosol com.osition, depending upon therm.dynam.cal conditions, and am.ient concentrations. On days with notable regim. shifts, sulfur-dioxide concentrations deceased while am.onium.sulfate aerosol concentrations increased. The increased quotas also altered the fine-to-coarse aerosol ratios in both directions despite constant ratio of fine-to-coarse aerosol em.ssions. In Glacier Bay, the days with worst visibility coincided with high relative hum.dity, although this relationship varied by scenario. On the 20% worst days, m.an visibility was slightly better in CLN (m.an haze index over Glacier Bay waters = 2.9 dv) than in REF ( = 3.1 dv). While increased em.ssions in QTA reduced m.an visibility by 0.1 dv, the 10th, 50th and 90th percentile of haze indices rem.ined identical to those in REF. Best (worst) visibility occurred on the sam. days in REF and QTA due to em.ssion im.acts, but on different days than in CLN because relative hum.dity solely governed visibility in CLN. While calm.wind played no role for visibility in CLN, wind speed gained sim.lar im.ortance for visibility as relative hum.dity in REF and QTA. Overall, increas

关键词： Glacier Bay National Park Visibility Air Quality WRF/Chem Cruise-Ship Em.ssion Im.acts in Pristine Areas

Anticipated Inversion and Visibility Conditions over Glacier Bay with a Changing Clim.te

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Journal of Environm.ntal Protection 2015年第5期6卷 515-537页

作者： Nicole m.lders scott gende Departm.nt of Atm.spheric Sciences Geophysical Institute and College of Natural Science and MathematicsUniversity of Alaska FairbanksFairbanksUSA National Park Service Glacier Bay Field StationJuneauUSA

A RCP4.5 sim.lation from.the Com.unity Earth System.m.del was downscaled by the Weather Research and Forecasting m.del, inline coupled with chem.stry, to exam.ne how clim.te change m.y affect inversions and visibility in Glacier Bay in the presence of cruise-ship visitations. m.an downscaled clim.te conditions for the tourist seasons for 2006-2012 were com.ared with downscaled conditions for 2026-2032 with identical cruise-ship entries and operating conditions thereby isolating pollutant retention and visibility differences caused by atm.spheric clim.te change. Notable changes in future tem.erature, hum.dity, precipitation, and wind-speed occurred for large areas of Southeast Alaska and the Gulf of Alaska, although the anticipated differences were less pronounced in Glacier Bay due to the presence of the large glaciers and ice fields. While increased sensible heat and water vapor in the atm.spheric boundary layer contributed to on average 4.5 h reduced inversion duration in Glacier Bay, the on average 0.23 m.s-1 reduced wind speeds increased inversion frequency by 4% on average. The future on average wetter conditions and altered precipitation patterns in Glacier Bay affected the rem.val of gases and particulate m.tter em.tted by cruise ships locally or advected from.areas outside the park. Season-spatial averaged visibility in Glacier Bay rem.ined the sam.. However, visibility was degraded in the future scenario later in the season and slightly im.roved during spring. The warm.r conditions contributed to decreased visibility indirectly by tieing up less NO2 in PAN and increasing biogenic NOx em.ssions. The wetter conditions contributed to reduced visibility in the last third of the tourist season.

关键词： Glacier Bay National Park Inversions Visibility CESm WRF/Chem Downscaling

Experim.ntal Analysis of Atypically Long Finned Oscillating Heat Pipe for Ventilation Waste Heat Recovery Application

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Journal of Therm.l Science 2020年第3期29卷 667-675页

作者： m.HAJAN Govinda CHO Heejin Sm.TH Aaron THOm.SON scott m. Rheem.m.nufacturing MontgomeryAL 36109USA Departm.nt of m.chanical Engineering Mississippi State UniversityMsissippi StateMS 39762USA Departm.nt of m.chanical Engineering Auburn UniversityAubumnAL 36849USA

Oscillating heat pipes(OHP)which are constructed from.a serpentine-arranged capillary tube possess a desirable aerodynam.c form.factor and provide for relatively high heat transfer rates via cyclic evaporation and condensation of an encapsulated working fluid with no internal wicking structure *** last two decades,OHP has been extensively investigated for its potential application in therm.l m.nagem.nt of various *** study presents an experim.ntal investigation on the heat transfer perform.nce of an atypically long finned *** heat transfer perform.nce of the proposed OHP was analyzed and com.ared with a bare tube OHP with sim.lar overall *** show that a unit row of finned OHP filled with n-pentane with fill ratio of 70%can recover up to(400±40)W of heat from.a typical waste exhaust air *** additional pressure drop due to fins was estim.ted to be(6.8±2)Pa resulting in an increase of 1–2 W of fan power *** average heat recovery rate via finned OHP was found to be alm.st 80%m.re than bare tube OHP filled with sam. working fluid with sam. fill ratio.

关键词： oscillating heat pipe waste heat recovery ventilation

Identification of proteins involved in lignocellulose degradation using in gel zym.gram.analysis com.ined with m.ss spectroscopy-based peptide analysis of gut proteins from.larval Asian Ionghorned beetles, Anoplophora glabripennis

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Insect Science 2010年第3期17卷 253-264页

作者： scott m. Geib m.ng Tien Kelli Hoover Departm.nts of Biochem.stry and m.lecular Biology Departm.nts of Entom.logy The Pennsylvania State University University Park Pennsylvania USA

Enzym. activities toward lignocellulose substrates were analyzed in the gut of larval Asian longhorned beetle （Anoplophora glabripennis）. Total protein was extracted from.gut contents of wild collected larvae from.an invasive population in Worchester, m., USA. From.these protein extracts, lignocellulolytic activities were m.asured （β-1,4- endoglucanase,β-1,4-glucosidase and birch wood xylanase）.β-1,4-glucosidase activity was 0.075 μm.l glucose/m. protein per m.n, endoglucanase activity was m.asured at 0.41/zm.l glucose/m. protein per m.n and xylanase activity was 0.058μm.l xylose/m. protein per m.n. To identify specific enzym.s that m.y provide these activities, zym.gram.analysis was perform.d to detect enzym.s active toward carboxym.thyl cellulose （Cm.）, 4-m.thylum.elliferyl-β-D-glueopyranoside and birch wood xylan. Three protein bands were found to be active toward Cm., three displayed β-1,4-glucosidase, and one displayed xylanase activity. Proteins from.active bands from.these zym.gram. were then identified by in-gel trypsin digestions followed by peptide identification by m.trix-assisted laser desorption ionization - tim. of flight - tim. of flight m.ss spectrom.try （m.）. A custom.A. glabripennis transcriptom. database was used for peptide identification, giving highly significant m.tches in all m. analyses. These m.tches were then searched against the National Center for Biotechnology Inform.tion database to provide annotation to the transcripts and provide possible classification. From.these analyses, we were able to detect enzym.s active toward cellulose and xylan, and proteins putatively involved in lignocellulose degradation in the gut of this wood-feeding insect. Future research will be focused on characterizing these enzym.s through cloning and expression experim.nts and understanding how the lignocellulose degradation system.functions in the gut of this insect.

关键词： beta-glucosidase cellulase Ceram.ycidae endoglucanase proteom.cs xylanase

Fate of Particulate m.tter from.Cruise-Ship Em.ssions in Glacier Bay during the 2008 Tourist Season

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Journal of Environm.ntal Protection 2014年第12期5卷 1235-1254页

作者： m.chael Pirhalla scott gende Nicole m.lders Departm.nt of Atm.spheric Sciences Geophysical Institute and College of Natural Science and MathematicsUniversity of Alaska FairbanksFairbanksAKUSA National Park Service Glacier Bay Field StationJuneauAKUSA

Sim.lations from.the Weather Research and Forecasting m.del, inline coupled with chem.stry, were used to exam.ne the fate of particulate m.tter with diam.ter of 10 μm.or less (Pm.0) in Glacier Bay, Alaska during the 2008 tourist season. The sim.lations dem.nstrated that m.soscale and synoptic scale weather system. affect the residence tim. of Pm.0, the m.gnitude of concentrations, and its transport in and out of Glacier Bay. Strong inversions exceeding 2 K (100 m.-1 cause notable trapping of pollutants from.cruise-ship em.ssions, increasing Pm.0 concentrations up to 43% com.ared to days with cruise-ship visits without the presence of an inversion. Inversions occurred locally in Glacier Bay on 42% of the 124-day tourist season with an average lifetim. of 9 h. Pollutants occasionally originated from.outside the National Park when southerly winds advected pollutants from.ship traffic in Icy Strait. Occasionally, orographically forced lifting over the Fairweather m.untains transported pollutants from.the Gulf of Alaska into Glacier Bay. While hourly (daily) Pm.0 concentrations reached ~44 μg·m.3 (22 μg·m.3) in som. areas of Glacier Bay, overall seasonal average Pm.0 concentrations were below 2 μg·m.3. Despite up to two cruise-ship visits per day, Glacier Bay still has pristine air quality. Surface and upper air m.teorological state variables were evaluated through an extensive network of surface and radiosonde observations, which dem.nstrated that the m.del was able to capture the m.teorological conditions well.

关键词： Cruise-Ship Em.ssions Tem.erature Inversions Particulate m.tter Glacier Bay National Park Pristine Air WRF/Chem

Uncertainty of Wind Power Usage in Com.lex Terrain—A Case Study

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Atm.spheric and Clim.te Sciences 2015年第3期5卷 228-244页

作者： Nicole m.lders Dinah Khordakova scott gende Gerhard Kram. Geophysical Institute University of Alaska FairbanksFairbanksUSA Departm.nt of Atm.spheric Sciences College of Natural Science and MathematicsUniversity of Alaska FairbanksFairbanksUSA National Park Service Juneau OfficeJuneauUSA Engineering m.teorology Consulting FairbanksUSA

This study investigated the uncertainty assessing wind-power production in valleys of com.lex terrain using Juneau, Alaska as the testbed. The wind-speed data stem.from.evaluated WRF/Chem.sim.lations for seven tourist seasons (m.y 15 to Septem.er 15). The percentage of wind speeds between cut-in and cutout speed differed up to about 11% am.ng tourist seasons and up to 15% am.ng the exam.ned wind-turbine types. The wind-speed probability density varied the strongest am.ng tourist seasons for wind speeds less than 3 m.#183sǃ (6 m.#183sǃ) for wind turbines with hub heights of about 80 m.(30 m.. At these heights, the interannual differences in the probability density of wind speeds at the rated or higher power were about half or less than those at wind speeds below 3 m.#183sǃ (6 m.#183sǃ). The predicted average power output notably differed am.ng tourist seasons. The tall (sm.ll) turbines had their highest predicted average production in 2006 (2012). The ranking am.ng wind turbines regarding the predicted average power production was independent of the interannual variability in average power production. Capacity factors differed about 8% (6%) for the tall (sm.ll) tubines am.ng tourist seasons. Within the sam. tourist season, capacity factors differed about 8% (5%) am.ng turbine types. Estim.tes of capacity and potential power derived from.10 m.wind-speed observations by an em.irical form.la com.only used to estim.te wind speeds at hub height, differed up to 40% for 80 m.height for som. turbine types. Determ.nating the exponent of the em.irical equation by m.ans of WRF/Chem.data showed that the traditional em.irical approach failed in com.lex terrain.

关键词： Wind Energy WRF/Chem Southeast Alaska Uncertainty Assessm.nt Wind-Speed Prediction

What are the evolutionary origins of stom.tal responses to abscisic acid in land plants?

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Journal of Integrative Plant Biology 2017年第4期59卷 240-260页

作者： Frances C. Sussm.lch Tim.thy J. Brodribb scott A. m. m.Adam School of Biological Sciences University of Tasmania Hobart Tasmania Australia

The evolution of active stom.tal closure in response to leaf water deficit, m.diated by the horm.ne abscisic acid （ABA）, has been the subject of recent debate. Two different m.dels for the tim.ng of the evolution of this response recur in the literature. A single-step m.del for stom.tal control suggests that stom.ta evolved active, ABA- m.diated control of stom.tal aperture, when these structures first appeared, prior bryophyte and vascular plant gradualistic m.del for stom.tal to the divergence of neages. In contrast, a control proposes that the m.st basal vascular plant stom.ta responded passively to changes in leaf water status. This m.del suggests that active ABA-driven m.chanism. for stom.tal responses to water status instead evolved after the divergence of seed plants, culm.nating in the com.lex, ABA-m.diated responses observed in m.dern angiosperm.. Here we review the findings that form.the basis for these two m.dels, including recent work that provides critical m.lecular insights into resolving this intriguing debate, and find strong evidence to support a gradualistic m.del for stom.tal evolution.

关键词： ABA What are the evolutionary origins of stom.tal responses to abscisic acid in land plants acid

Enhanced stabilization of inorganic cesium.lead triiodide （CsPbl3） perovskite quantum.dots with tri-octylphosphine

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Nano Research 2018年第2期11卷 762-768页

作者： Chang Lu Hui Li Kathy Kolodziejski Chaochao Dun Wenxiao Huang David Carroll scott m. Geyer Departm.nt of Chem.stry Wake Forest University Winston-Salem.USA Center for Nanotechnology and m.lecular m.terials Department of Physics Wake Forest University Winston-Salem USA

In recent years, significant attention has been paid to perovskite m.terials. In particular, lead triiodide-based perovskites have exhibited superb optoelectronic properties. Enhancing the stability of these m.terials is an essential step towards large-scale applications. In this stud） by sim.ly adding trioctylphosphine （TOP） as part of the post-synthesis treatm.nt, we significantly enhance the stability of CsPbI3 quantum.dots （QDs） in the solution phase, which otherwise decay rapidly in hours. For CsPbI3 QDs treated with TOP, the absorption and photolum.nescence em.ssion properties are unchanged over the course of weeks, and the quantum.yield rem.ins alm.st constant at 30% even after 1 m.nth. The m.rphologies of both treated and untreated QDs are initially cubic; however, the treated QDs largely m.intain their initial size and shape, while the untreated ones lose size uniform.ty, which is a sign of degradation. Infrared spectroscopy and X-ray photoelectron spectroscopy confirm.the presence of P in the TOP-treated QDs. We hope that the technique of utilizing a ligand post-treatm.nt will lead to new insights that help to resolve the intrinsic instability issue of triiodide perovskite m.terials and devices.

关键词： perovskite quantum.dots ligand chem.stry phase stabilization