Top PDF Gaseous elemental and reactive mercury in southern New Hampshire

Gaseous elemental and reactive mercury in southern New Hampshire

Gaseous elemental and reactive mercury in southern New Hampshire

shown in Fig. 9. These represent ∼14% of all observations at each site during 2007. High Hg ◦ events were observed under southerly to westerly flow patterns in spring and fall (Fig. 9b, d), while none in summer with all values <230 ppqv (Fig. 9c). This could suggest the dominant role of localized sinks at TF in warm seasons (Mao et al., 2008). PM exhibited a more pronounced directional dependence for each season with

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Oxidation of elemental Hg in anthropogenic and marine airmasses

Oxidation of elemental Hg in anthropogenic and marine airmasses

During the last decade the measurements of atmospheric mercury (Hg) have developed substantially. Speciated Hg measurements, including gaseous elemental mercury (GEM), reactive gaseous mercury (RGM), and particle bound mercury (PBM) (Landis et al., 2002), are providing important information about mercury sources, transforma- tion and subsequent deposition (e.g., Talbot et al., 2008; Peterson et al., 2009; Gustin and Jaffe, 2010; Sprovieri et al., 2010). Mercury is mainly emitted to the atmosphere in its elemental form, which has a long lifetime allowing global transport (Jaffe et al., 2005; NRC, 2010). Atmo- spheric oxidation of GEM generates gas- and particle-phase oxidized Hg compounds (thought to be primarily inorganic Hg(II) species) that deposit quickly as they are more reac- tive, more water-soluble, and less volatile (Schroeder and Munthe, 1998; Lin and Pehkonen, 1999; Holmes et al., 2009; NRC, 2010). The spatial distribution of mercury deposition in many instances might thus depend more on atmospheric conditions (e.g. wind direction, oxidant concentrations, tem- perature) than on proximity to mercury sources (Chand et al., 2008; Sprovieri et al., 2010; Holmes et al., 2010; Rothenberg et al., 2010).
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Deciphering potential chemical compounds of gaseous oxidized mercury in Florida, USA

Deciphering potential chemical compounds of gaseous oxidized mercury in Florida, USA

Abstract. The highest mercury (Hg) wet deposition in the United States of America (USA) occurs along the Gulf of Mexico, and in the southern and central Mississippi River Valley. Gaseous oxidized Hg (GOM) is thought to be a ma- jor contributor due to high water solubility and reactivity. Therefore, it is critical to understand concentrations, po- tential for wet and dry deposition, and GOM compounds present in the air. Concentrations and dry-deposition fluxes of GOM were measured and calculated for Naval Air Sta- tion Pensacola Outlying Landing Field (OLF) in Florida us- ing data collected by a Tekran ® 2537/1130/1135, the Univer- sity of Nevada Reno Reactive Mercury Active System (UN- RRMAS) with cation exchange and nylon membranes, and the Aerohead samplers that use cation-exchange membranes to determine dry deposition. Relationships with Tekran ® - derived data must be interpreted with caution, since the GOM concentrations measured are biased low depending on the chemical compounds in air and interferences with water va- por and ozone.
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Centralization And Decentralization In Planning

Centralization And Decentralization In Planning

The centralconcept ofmeanconcentration ofall decisionsand policies related tothe process ofplanning and developmentunder the control ofcertain partiesarebodiesplanningindifferent countries, andis embodiedministriesorplanningcouncilsin most countries, and itshall issue its decisionsto thespecialized committeesin order to betranslated intodevelopment plansturningtovarious international institutions,tobeing implementedinparticipation andthispushesresearcherstosay thatthe basicsfrom thehigh authorities ofplanning institutionstorankat leastasordersarenon-negotiable. (Khamis0.1999m) Theresearcheraddsthat the centralconceptconsists ofthree maindecisionsare:
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Gonçalo Jorge Dias do Vale

Gonçalo Jorge Dias do Vale

More than three years have passed since I have started my PhD project. Three years enriched with experiences and adventures where in some moments I had the privilege of travelling and meet new people. Some of these persons have become friends with whom throughout these years I have shared joys and sadness, victories and frustrations. It is to all these persons whom, directly or indirectly where involved in my PhD project that I dedicate these paragraphs. First of all I would like to thank my family which was, at many times, left behind into second line because of my work, but they were always there in all the moments, supporting me. To my parents for always supporting me and helping me in the hardest decisions I needed to take with wise advices. To my other parents, my grandparents: Vitória and Francisco, for the trust and support even though not having the slightest idea of what I was doing during this period of time. To Sara, because she always was there for me and for be simply the best person I have ever met- thank you for be as you are. To the memory of my grandmother Gracinda, to my aunt Elisabete for all the scientifically argues we had where I unsuccessfully tried to convince her that I was not working on Bioterrorism. To my uncle “Tó Zé”, Maria João and Beatriz, for all the love and support. And to all the other members of my family and friends for stand by and hearing me in the good and bad times, specially to Joana, Cristina, Margarida and Tiago, who suffered greatly – a big thank to you.
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Environmental Conditions Associated with Elevated Vibrio parahaemolyticus Concentrations in Great Bay Estuary, New Hampshire.

Environmental Conditions Associated with Elevated Vibrio parahaemolyticus Concentrations in Great Bay Estuary, New Hampshire.

Reports from state health departments and the Centers for Disease Control and Prevention indicate that the annual number of reported human vibriosis cases in New England has increased in the past decade. Concurrently, there has been a shift in both the spatial distri- bution and seasonal detection of Vibrio spp. throughout the region based on limited monitor- ing data. To determine environmental factors that may underlie these emerging conditions, this study focuses on a long-term database of Vibrio parahaemolyticus concentrations in oyster samples generated from data collected from the Great Bay Estuary, New Hampshire over a period of seven consecutive years. Oyster samples from two distinct sites were ana- lyzed for V. parahaemolyticus abundance, noting significant relationships with various biotic and abiotic factors measured during the same period of study. We developed a predictive modeling tool capable of estimating the likelihood of V. parahaemolyticus presence in coastal New Hampshire oysters. Results show that the inclusion of chlorophyll a concentra- tion to an empirical model otherwise employing only temperature and salinity variables, offers improved predictive capability for modeling the likelihood of V. parahaemolyticus in the Great Bay Estuary.
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J. Braz. Chem. Soc.  vol.16 número5

J. Braz. Chem. Soc. vol.16 número5

spectrophotometric methods are prone to interferences which arise from concomitants (mainly other metal ions) that could affect the accuracy of the determination by promoting a side reaction with the chromogenic agent and/ or by competing with mercury in the pre-concentration step. On the other hand, the spectrophotometric method is less expensive and can be developed to employ portable, low cost equipment. The overall cost per analysis can be reduced and in-field determinations can be implemented without the constraints imposed by the use of atomic absorption (CVAA or GFAAS) or atomic fluorescence, that require more sophisticated, expensive instrumentation with high power requirements.
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Overview of mercury measurements in the Antarctic troposphere

Overview of mercury measurements in the Antarctic troposphere

Simpson, W. R., von Glasow, R., Riedel, K., Anderson, P., Ariya, P., Bottenheim, J., Bur- rows, J., Carpenter, L. J., Frieß, U., Goodsite, M. E., Heard, D., Hutterli, M., Jacobi, H.-W., Kaleschke, L., Neff, B., Plane, J., Platt, U., Richter, A., Roscoe, H., Sander, R., Shepson, P., Sodeau, J., Steffen, A., Wagner, T., and Wolff, E.: Halogens and their role in polar boundary- layer ozone depletion, Atmos. Chem. Phys., 7, 4375–4418, 2007,

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Quím. Nova  vol.35 número5

Quím. Nova vol.35 número5

ether (5+1 by volume, 21 mL) and stirred in order to dissolve the precipitate formed. The phases were separated and extractions with diethyl ether were performed (2 x 10 mL). The combined organic phases were washed with sodium chloride saturated solution (15 mL), dried over magnesium sulphate and concentrated under redu- ced pressure. To the yellow oil thus obtained it was added a mixture previously prepared of sodium acetate (106, 125 and 114 mg for 7a, 7b and 7c, respectively), acetic acid (4.5 mL), formalin (3.3 mL) and diethylamine (1.2 mL). The reaction mixture was vigorously shaken for one minute and then heated on a stream bath for 5 min, cooled and poured into water (45 mL) and ether (30 mL). The organic phase was washed with water (15 mL), saturated NaHCO 3 aqueous solution (15 mL), dried over MgSO 4 and concentrated under
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SYSTEMATIC ACCOUNT Family Philosciidae Kinahan, 1857 Genus Benthana Budde‑Lund, 1908

SYSTEMATIC ACCOUNT Family Philosciidae Kinahan, 1857 Genus Benthana Budde‑Lund, 1908

Remarks: The male pleopod 1 exopod of Benthana carijos sp.  nov. is similar to that of B.  bocainensis Lemos de Castro, 1958, B. santosi Lemos de Castro, 1958 and B. schubarti Lemos de Castro, 1958, by the not prominent dentiform protrusion and low inden- tation, but can be distinguished by the absence of lobe on the inner margin (vs. present in B.  bocainensis), and presence of setae on outer margin (vs. absent in B. santosi and B. schubarti). Benthana carijos sp. nov. can also be distinguished by the number of aesthetascs on the antennule (16+2 vs. 8+2 in B. bocainenis, 9+2 in B. santosi, and 6+2 in B. schubarti), uropod exopod slightly longer than endopod (vs. exopod twice as long as endopod in all three species), and the shape of the male pleopod 1 exopod with narrow distal third, an unique characteristic of this species.
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Temporal variability, sources, and sinks of C<sub>1</sub>-C<sub>5</sub> alkyl nitrates in coastal New England

Temporal variability, sources, and sinks of C<sub>1</sub>-C<sub>5</sub> alkyl nitrates in coastal New England

samples collected throughout 12 January 2004 to 8 Febru- ary 2008 are also presented. The ambient air samples were collected at approximately noon (local time) from the top of the 12 m tower at TF. The four year data set was sep- arated into four seasons which are defined as winter: De- cember, January, February; spring: March, April, May; sum- mer: June, July, August; fall: September, October, Novem- ber. Note that the data includes five winter seasons (2004– 2008) and four spring, summer, and fall seasons (2004– 2007). The samples were analyzed in the lab at UNH every 1–3 months for a large suite of volatile organic compounds (C 2 -C 10 NMHCs, C 1 -C 5 alkyl nitrates, C 1 -C 2 halocarbons,
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CD7.R17: Report of the permanent subcommittee on buildings and installations

CD7.R17: Report of the permanent subcommittee on buildings and installations

Committee, to the effect that the construction work for the fourth floor of the building located at. 1501 New Hampshire Avenue, N[r]

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Ângelo Parise Pinto 1,2 Carlos José Einicker Lamas

Ângelo Parise Pinto 1,2 Carlos José Einicker Lamas

The current rate of the species descriptions of South American corduliids is impressive; half of the 43 species was described in the last twenty years and almost one-third within the current decade (based on data from Garrison 2009). All recently described species are from the Neotropical portion of the continent (sensu Morrone 2006), while the corduliids from Andean region / South American transition zone seem near to be completely discovered, although there is at least one undescribed species of Gomphomacromia from Colombia (R. Garrison pers. comm.). One would relate the data to the recent increase in field surveys, but after checking the collecting dates in respective type series we were able to realize that just the smaller part (40%) of the descriptions was based on specimens collected in the last two decades. This scenery is accentuated in Navicordulia, since from the total of eight species described in the last twenty years; seven of them were based on specimens collected at maximum in the decade of 1980. It can demonstrate a trend of reduction of collection expeditions and it becomes critical to increment actions for promote future field surveys. The Neotropical region is largely considered to be the richest dragonfly biota of the World and also the least studied (Kalkman et al. 2008; von Ellenrieder 2009). Corduliids are poorly represented in this region, however they have been shown to be richer than previously expected and probably several new taxa will be discovered. Furthermore, there is a gap in biological and ecological knowledge of South American ‘Corduliidae’ facing the current biodiversity crisis (see Clausnitzer et al. 2009), field surveys must be the priority effort for assessment of the diverse dragonfly fauna of tropical South America (von Ellenrieder 2009; Pinto & Carvalho 2010).
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Speciated mercury at marine, coastal, and inland sites in New England – Part 1: Temporal variability

Speciated mercury at marine, coastal, and inland sites in New England – Part 1: Temporal variability

and 119 km north of PM, respectively. This is consistent with observations from other geographic locations, such as the site on the eastern slope of Mt. Gongga in China (Fu et al., 2008) with two industrial areas located 50–60 km south and southeast of the sampling site, where RGM is lost relatively fast via dry deposition after leaving its sources. Third, larger median and 90th percentile mixing ratios were observed in the

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Redescription and new distributional records of Matuta planipes (Fabricius, 1798) (Crustacea; Decapoda; Matutidae) from Chennai Coast, Tamil Nadu

Redescription and new distributional records of Matuta planipes (Fabricius, 1798) (Crustacea; Decapoda; Matutidae) from Chennai Coast, Tamil Nadu

During the survey of brachyuran fauna of Matuta planipes (Fabricius, 1798) has four adult female and two male species were collected in Chennai coast using trawl net. Trawl net hauled from depth of 40 m to 60 m. The specimen was preserved in 10% formalin and its taxonomy was confirmed to species level using various literatures (Sethuramalingam and Ajmalkhan, 1991; Jayabaskaran et al., 2000). The specimen was deposited in the Department of Zoology, Sir Theagaraya College, Chennai, Tamil Nadu, India.

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Two years of measurements of atmospheric total gaseous mercury (TGM) at a remote site in Mt. Changbai area, Northeastern China

Two years of measurements of atmospheric total gaseous mercury (TGM) at a remote site in Mt. Changbai area, Northeastern China

From 24 October 2008 to 31 October 2010, TGM concen- tration in ambient air was continuously monitored using an automated Hg vapor analyzer (Tekran 2537A). The opera- tion of the instrument relying on pre-concentration of TGM onto gold traps, followed by thermal desorption, and detec- tion of Hg 0 by cold vapor atomic fluorescence spectrometry. The instrument features two gold cartridges working in par- allel. While one cartridge is collecting TGM, the other one is performing analysis of the collected TGM. The function of the cartridges is then reversed, allowing continuous sam- pling of ambient air. The sampling inlet was mounted at a height of 2∼3 m above the forest canopy by using a 25 m Teflon tube and a 15 m heated Teflon tube. Particulate matter in ambient air was removed using a 45-mm diameter Teflon filter (pore size 0.2 µm) upstream of the analyzer, which was replaced every two week. It should be noted that an unknown fraction of GOM in the TGM was likely lost during passing the 25-m un-heated Teflon tube due to its adsorption to tube inner surface and particles. However, it is not well known that how much percent of GOM was stuck by the sampling Teflon tube, and whether the stuck GOM could be transformed to GEM and sequentially determined by the Hg vapor analyzer. Since GOM generally constitutes a small fraction (<1 %) of TGM in ambient air and the loss of GOM only had very limited effect on measured atmospheric Hg, we referred at- mospheric Hg as TGM throughout the paper and just aimed to have a good accordance with TGM measurements in other literatures. The analyzer was programmed to measure atmo- spheric TGM at a time resolution of 5 min and at a sampling flow rate of 1.0 L min −1 (Sampling flow rate and volume are referenced to 0 ◦
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A new species of Bryconamericus (Characidae: Stevardiinae: Diapomini) from the upper rio Paraná basin, Brazil

A new species of Bryconamericus (Characidae: Stevardiinae: Diapomini) from the upper rio Paraná basin, Brazil

are listed as (GM) in the list of type-material and material examined. Individual photographs were taken with 10 Mpixels resolution digital camera. Photograph files were grouped and transformed in *.tps files using TPSUtil V. 1.86 program (Rohlf, 2015). Landmarks were traced with the assistance of TPSDig V.2.2 program (Rohlf, 2015). The landmarks were aligned with procrustes superimposition 2D option of the program PAST (Hammer et al., 2001), and the same program was used for the multivariate canonical variate analysis (MANOVA/CVA option) and principal components analysis (Principal Components option) (Hammer et al., 2001). The procrustes superimposition eliminates variations in position, scale, and orientation of landmarks (Klingenberg, 2002), superimposing all individuals, adjusting and centering each configuration between homologous landmarks, and generating a reference configuration. The following landmarks were traced on each specimen: 1) contacting point of anterior tip of dentary with premaxilla; 2) tip of snout; 3) anterior border of snout; 4) posterior tip of maxillary bone; 5) anterior margin of eye; 6) posterior margin of eye; 7) posterior tip of supraoccipital process; 8) contacting point between posterior margin of third and fourth infraorbitals; 9) posterior margin of opercle; 10) pectoral-fin base; 11) dorsal-fin origin; 12) posterior insertion of dorsal fin; 13) adipose-fin origin; 14) posterior insertion of adipose fin; 15) tip of penultimate dorsal procurrent ray; 16) tip of penultimate ventral procurrent ray; 17) posterior insertion of anal fin; 18) anal-fin origin; and 19) pelvic-fin origin.
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If there were a ‘Highly Skilled Red Octopus’? The Case of Italian Highly Skilled Mobility at Times of Crisis

If there were a ‘Highly Skilled Red Octopus’? The Case of Italian Highly Skilled Mobility at Times of Crisis

This paper has looked at the dynamics of highly skilled workers‟ mobility from Italy considering the phase of economic crisis that the country is still experiencing. Although the available literature on current highly skilled migration from Italy is still in its infancy, two recent empirical researches have been critically discussed. These two studies are relevant mainly because they provide evidence of the fact that a certain amount of talented Italians is headed in a range of countries, which are not part of the traditional „core‟, namely Southern and Eastern European countries. Thus, it is reasonably clear that reducing the mobility of highly skilled Italians today to a South-North movement represents an oversimplification of reality. Indeed, the „blue banana‟ – and, by extension, the migrations for economic reasons – can only partially explain the wide variety of movements that is taking place nowadays among the highly skilled Italians.
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Bimodal variation in mercury wet deposition to the coastal zone of the southern Baltic

Bimodal variation in mercury wet deposition to the coastal zone of the southern Baltic

Ebinghaus, R., Jennings, S. G., Schroeder, W. H., Berg ,T., Donaghy, T., Guentzel, J., Kenny, C., Kock, H. H., Kvietkus, K., Landing, W., M ¨uhleck, T., Munthe, J., Prestbo, E. M., Schnee- berger, D., Slemr, F., Sommar, J., Urba, A., Wallschl ¨ager, D., and Xiao, Z.: International field intercomparison measurements of atmospheric mercury species at Mace Head, Ireland, At- mos. Environ., 33, 3063–3073, 1999.

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J. Braz. Chem. Soc.  vol.10 número2

J. Braz. Chem. Soc. vol.10 número2

Efforts to develop flow systems for the determination of gaseous analytes in gaseous samples are critically reviewed. Although flow systems present a suitable alternative to management and processing of gaseous samples, relatively few papers dealing with this subject are found in the literature. The increased demand for determination of gaseous analytes, the advent of automated systems based on microcomputers and new devices, such as miniature solenoid valves, which facilitate manipulation of gaseous samples, and the easy access to gaseous standards has, along, driven some recent progress towards the use of flow systems. Flow systems constitute a versatile option capable to be applied to a wide concentration range, rapid, easy to operate with relatively low sample volume, becoming a low cost approach for determination of gaseous analytes.
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