1,721,011 research outputs found
Natural surface-film studies in shallow coastal waters of the Baltic and Mediterranean seas.
No full textAuthor to whom correspondence should be addressed at: Environmental Acoustics Laboratory, University of Gdansk, Wita Stwosza 57, 80–952 Gdansk, Poland
New molecularly-imprinted electrochemical sensors for perfluorooctansulfonate and analytical methods based thereon
No full textTrace Electroanalysis of Perfluorinated Alkyl Substances with Molecularly Imprinted Polymer Sensors
No full textPollution of natural and drinkable waters by perfluorinated alkyl substances (PFAS) is a problem of global concern [1]. [...
NUOVI SENSORI ELETTROCHIMICI A STAMPO MOLECOLARE PER PERFLUOROOTTANOSOLFONATO E SUOI DERIVATI
No full textSurfactant and particulate matter exchange at the air-water-interface in the antarctic environment.
No full textPublisher: SOC CHIMICA ITALIANA, VIALE LIEGI 48, I-00198 ROME, ITALY
Web of Science Category: Chemistry, Analytical; Environmental Sciences
Subject Category: Chemistry; Environmental Sciences & Ecolog
Formaldehyde determination in seawater. Preliminary applicationto coastal samples at Terra Nova Bay (Antarctica)
Full text linkA sensitive spectrofluorimetric-FIA (flow injection analysis) method for formaldehyde (HCHO)
determination was improved with the aim of analysing seawater samples.The fluorescence emission versus
HCHO concentration shows a linear pattern from sub mg L1 to about 1000 mg L1. The reproducibility at
15 ppb level is about 2%. Interferences from other aldehydes were checked; only glyoxal shows a
significative interference, but only when its concentration is about 6000 times higher than that of
formaldehyde. Superficial (microlayer, just sub-pack or sea-ice free sea surface) and deep (along the water
column, sub-pack or in sea-ice free areas) seawater samples were collected near the coast at Terra Nova Bay
(Ross Sea, Antarctica) during the 1998/1999 and 2001/2002 Italian Antarctic Expedition. We report here the
preliminary results of the spectrofluorimetric-FIA determination of the HCHO content. The mean seawater
superficial formaldehyde concentration was 15 mg L1; the concentration along the water column ranged
between 4.5 to over 40 mg L1 (20 mg L1 mean concentration), usually with a maximum value for the 30 m
depth, corresponding to a fluorescence maximum. The sampling was repeated 7 times in the austral summer
in order to evaluate seasonal changes in the formaldehyde concentration/seawater depth profiles. The results
show changes in the formaldehyde concentration at different depths
Fulvic-acids in the antarctic snow via marine aerosol
No full textPublisher: SOC CHIMICA ITALIANA, VIALE LIEGI 48, I-00198 ROME, ITALY\ud
Web of Science Category: Chemistry, Analytical; Environmental Sciences\ud
Subject Category: Chemistry; Environmental Sciences & Ecolog
Enrichment of organic pollutants in the sea surface microlayer (SML) at Terra Nova Bay, Antarctica: influence of SML on superficial snow composition.
Full text linkConcentrations of dissolved and particle-associated n-alkanes, phthalates and polycyclic aromatic
hydrocarbons (PAHs) were measured in sea surface microlayer (SML) and sub-surface water (SSL) samples
collected in the coastal area of Terra Nova Bay, Antarctica, during the Austral spring 1998/1999. SML
concentrations of the selected organic compounds were higher than SSL values and the enrichment factors
were greater in the particulate phase than in the dissolved phase. During the same campaign, ‘‘fresh’’ snow
samples, collected at different altitudes (from sea level up to 2670 m) near the coast on Mt Melbourne,
immediately after a snowy event, were analysed in order to provide more information on air/sea exchange
processes. The same classes of organic compounds found in sea water were also present in ‘‘fresh’’ snow
samples. The surfactant fluorescent organic matter (SFOM), adsorbed on the microdrop aerosol surface,
could be considered the main constituent of the enrichment and the carrier at higher altitudes of organic
compounds. In fact, hydrocarbons (n-alkanes and PAHs), which are not surfactants like phthalates, could
interact with SFOM and follow the same fate
PRELIMINARY ASSESSMENT ON THE ELECTROCHEMICAL SYNTHESIS OF 1-D JANUS PARTICLES FOR CHEMICAL SENSING PURPOSES
Full text linkThe dual nature of Janus particles (JPs) confers upon them fascinating properties. The name of this particles is referred to the Roman god of gates, having two opposite and distinct faces. In practice, the term Janus Particles defines all those particles displaying a dual anisotropic structure, in which two parts with distinct characteristics can be distinguished. Possible architecture for JPs are schematized in Fig. 1. \ud
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Figure 1. Different Janus Particles arrangements.\ud
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JPs have been prepared by a variety of methods, including: surface coating, biphasic electrified jetting, photo-polymerization in microfluidic channels, polymer self-assembly (1). Bipolar electrochemistry (2) have been applied to the goal of preparing JPs, with the advantages of requiring simple and cheap instrumentation as well as being potentially suitable for relatively\ud
large scale production. In this communication, we describe the\ud
electrochemical preparation of Janus like 1-D nanowires (J-NWs) in particular by bipolar electrochemistry and by membrane templated electrochemical deposition (3) exploiting the experimental set-up recently proposed (4). Advantages and limits of bipolar electrochemistry vs. template deposition are critically evaluated, taking into account that the final goal of this study is the synthesis of 1D JPs suitable for analytical applications, based on differentiated self-assembly of the J-NWS in response to changes of the chemical environment in which they are suspended.\ud
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(1) J. Hu, S. Zhou, Y. Sun, X. Fanga, L. Wu. Chemical Society Review, 41 (2012) 4356–4378.\ud
(2) G. Loget, V. Lapeyre, P. Garrigue,C. Warakulwit, J. Limtrakul, M.-H. Delville, A. Kuhn. Chemistry of Materials 23 (2011) 2595-2599.\ud
(3) P. Ugo, L.M. Moretto, Handbook of Electrochemistry, C. Zoski ed., chp. 16.2, Elsevier, 2007.\ud
(4) A. Gambirasi, S. Cattarin, M. Musiani, L. Vázquez-Gómeza, E. Verlato. Electrochimica Acta 56 (2011) 8582-8588
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