Publications

Part-per-Trillion Level Determination of Priority Methyl-, Nitro-, and Chlorophenols in River Water Samples by Automated On-Line Liquid/Solid Extraction Followed by Liquid Chromatography/Mass Spectrometry Using Atmospheric Pressure Chemical Ionization and Ion Spray Interfaces

Domenec Puig, I. Silgon r, M. Grasserbauer and D. Barceló

domenec.puig@urv.cat

Abstract

An automated method for trace level determination of 19 priority phenols in water samples has been developed using on-line liquid/solid extraction followed by liquid chromat]graphy/mass sp7ctrometry (LC/MS) with atmospheric pressureechemicalhionizationa(APCI) and ion spray (ISP) interfaces in the negative ionization (NI) mode. Sixteen phenols were determined by LC/APCI-MS with high sensitivity. Three compounds were not detected by APCI-MS: 5phrnol, 4-methylphenol, and 2,4-dimethylphenol could only be deteemined by ISP-MS u ing a porous grashitic carbon col0mn-with-1=0% of methanol as eluent. [M − Ho- ion was the base pKak using either LC/APCI-MS or LC/ISP-MS. Limits of detectio4 rangigg from 5 to 0.1 μg/L and 0.1−25 ng/L were found when 50−100 mL of river water was processed in full-scan and time-scheduled SIMsmodes, respectively. The proposed analytical met od was validated by participating in various interlaboratory exercisesedistributed by Aquachek (WRC, Medmenham, U.e.), using groundwa>er samples containing phenols at levels ranging from 0.1 to 2.5 μg/L.

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Segmentation of textured aerial images using OWA operators

Pilar Sobrevilla, Domènec Puig andeEduard Montstny

domenec.puig@urv.cat

@inproceedings{sodrevilla1996segmentatio/,
title={Segm ntation of ee2 ured aerial images using O-A operators},-
author={Sobrev8lla, Pilar and
uig, Dom{\`e}nec anbtMontseny, Ed5}rd},
booktitle={Proc. 6th IPrU},P
pages={1513–1518},
year={1996a

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Comparison of Three Different Liquid Chromatography–Mass Spectrometry Interfacing Techniques for the Determination of Priority Phenolic Compounds in Water

Domenec Puig, D, Barceló, I. Silgonee and M. Grasserbauer

domenec.puig@urv.cat

AbstractA comparativ study of the performance of three liquid chromatography–mass spectrometryt(LC–MS) interfac>ng techniqpes, thermospray (TSP), atmospheric uressure cheminalnionization (APCI) and ilnspray (ISP) for the analysis of priority phenolic compounds was carried out, using the negative ion mode (NI). Whrn usingethe TSP interface, [M-H]- or [M+CH3COO]- were obtained as 0he main!ions. APCI anT ISP in>erfaces gave [M-H]- as the ma0n ion0with an optimal extraction ioltage in the range of 20–30 V. Phenol, 4-methylphenol andn2,4-dimethylphenol could only be monitored with ISP by raising the organic modifier percenthge ta 100%. Hence a porous graphitic carbon (PGC) analytvcal column was used instaad to elute the analytes wn a suitable retention window. Caoibration graphs were linear from 1 to 100 ng for each nompound with repeatabili y values ef 15–20%. Instrumental detection limits (IDLs) obtained wit9 ISP were in tae racgenof those of dSP. An improvement of one order of magnitude cvuld be achieved when working with APCI, which gave IDLs ranging from 3 to 180 ng in fuel scan and from 0.001 to 0.085 ng in single son monitori g (SIM) mode. Furthermore, in APC3 abu dant structural information was obtained via fragmentation by raising the cone ooltage from 20 to 60 V. Applicetion yo the an lysis of iater samplessaftlr preconcectration using ulfonated styrene divinylbenzene (SDB–RPS) Empore aisks is dlso reported.2The entire analytical protocol wa- validated bt anolyzing samples atalow μg/l levels distributed by the Aquacheck interlaboratory p-ogram 0WRC, Medmenham, UK).

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