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Ajouter le résultat dans votre panier Affiner la rechercheDetermination of dimethylfumarate in leather and footwear by solid-phase micro extraction and gas chromatography-mass spectrometry / Rosa M. Cuadros in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CV, N° 12 (12/2010)
Titre : Determination of dimethylfumarate in leather and footwear by solid-phase micro extraction and gas chromatography-mass spectrometry Type de document : texte imprimé Auteurs : Rosa M. Cuadros, Auteur ; Joaquim Font, Auteur ; M. Reyes, Auteur ; Lluis Ollé, Auteur ; Agusti Marsal, Auteur Année de publication : 2010 Article en page(s) : p. 395-400 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Antifongiques
Chaussures
Chromatographie en phase gazeuse
Extraction (chimie)
Fumarate de diméthyle
Spectrométrie de masseIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : In the last two years, Europe has experienced a rise in skin allergy and dermatitis due to goods of an Asian provenance that have been treated with dimethylfumarate (DMFU). Accordingly, laboratories in the leather and footwear sectors have been obliged to develop analytical methods to determine the presence of this substance given the absence of an official method. The ban on DMFU as laid down in Decision 2009/251 of the European Union establishes a maximum concentration of DMFU in products of 0.1 mg/kg. A simple non-destructive rapid method based on manual headspace solid-phase micro extraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) is proposed to detect DMFU in leather and footwear. Thereafter, the samples in which DMFU is detected are analysed by a solid-liquid extraction (SLE) with acetone after which DMFU is quantitatively determined by GC-MS. The quantitative method is validated in terms of linearity, precision, sensitivity and recovery; demonstrating its reliability. Quantification is performed using naphthalene-D8 as internal standard. The detection limits are 0.005 mg/kg and 0.03 mg/kg for the HS-SPME-GC-MS and SLE-GC-MS methods, respectively. Given that these limits are below the maximum limit of 0.1 mg/kg imposed by the European Union, the proposed methods are suitable for determining DMFU content in real samples. En ligne : https://drive.google.com/file/d/1eWiehT0YKU5tnSg5VmUDIAbw7NBWyiYC/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=10505
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CV, N° 12 (12/2010) . - p. 395-400[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 012693 - Périodique Bibliothèque principale Documentaires Disponible
Titre : Determination of fungicides in residual tanning floats using solid phase micro extraction Type de document : texte imprimé Auteurs : Joaquim Font, Auteur ; M. Reyes, Auteur ; Sara Cuadros, Auteur ; Anna Bacardit, Auteur ; Lluis Ollé, Auteur ; Agusti Marsal, Auteur Année de publication : 2013 Article en page(s) : p. 41-47 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Adsorption
Antifongiques
Chromatographie en phase liquide à hautes performances
Cuirs et peaux -- Conservation
Désorption
DivinylbenzèneLe divinylbenzène (ou diéthénylbenzène en nomenclature systématique) est un hydrocarbure aromatique de formule C10H10. Comme son nom l'indique, il est constitué d'un noyau de benzène substitué par deux groupements vinyle (–CH=CH2). Il existe trois isomères du divinylbenzène, en fonction des positions relatives des groupements vinyle sur le noyau benzénique : 1. le 1,2-divinylbenzène ou orthodivinylbenzène, 2. le 1,3-divinylbenzène ou métadivinylbenzène, 3. le 1,4-divinylbenzène ou paradivinylbenzène.
PROPRIETES : Les composés ortho et méta sont à température et pression normales des liquides incolores, inflammables, irritant pour les muqueuses et se polymérisant facilement. Le composé para, dû à sa configuration particulière, a une température de fusion bien plus haute que les autres isomères (31 °C contre −67 °C pour les deux autres) et est donc solide à température ambiante. Ces trois composés sont insolubles dans l'eau.
UTILISATION : Les divinylbenzènes sont utilisés comme agent de réticulation dans des copolymères du polystyrène, ce qui réduit leur solubilité dans les solvants organiques, augmente leur résistance physique, leur dureté, leur résistance à la chaleur, sans affecter leur aspect et leurs propriétés optiques ou électriques.
Extraction en phase solide
PolydiméthylsiloxaneLe polydiméthylsiloxane —[O-Si(CH3)2]n—, ou poly(diméthylsiloxane) selon la nomenclature systématique, communément appelé PDMS ou diméthicone, est un polymère organominéral de la famille des siloxanes souvent présent dans les shampoings. On l'y ajoute pour augmenter le volume des cheveux mais il peut également aller boucher les pores du cuir chevelu et rendre les cheveux gras. C'est une des raisons pour lesquelles se laver les cheveux tous les jours est très déconseillé avec un shampooing contenant des silicones.
Il existe également de l'amodiméthicone, qui est un dérivé du diméthicone.
Le polydiméthylsiloxane est un additif alimentaire (E900), utilisé comme antimoussant dans les boissons (Coca-Cola BlāK).
La chaîne de poly(diméthylsiloxane) forme également la structure de base des huiles et des caoutchoucs silicones.Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Solid-phase microextraction (SPME) was optimized for extraction of the leather preservative agents 2-(thiocyanomethylthio)-benzothiazole (TCMTB), 4-chloro-3-methylphenol (PCMC), 2-phenylphenol (OPP), 2-Octyl-3(2H)-isothiazolone (OIT), 2-mercaptobenzothiazol (MBT) and 3-iodo-2-propynyl-butylcarbamate (IPBC) in spent tanning floats. Determination was carried out by high performance liquid chromatography (HPLC) with photo diode array detection (PDA). The following parameters were studied to achieve the maximum efficiency in extraction: fiber type, adsorption conditions (extraction time, ionic strength, temperature) and desorption parameters (time, temperature and composition of the desorption solvent). Results indicate that SPME using a 60µm polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber is appropriate for the extraction of these types of compounds. Recoveries ranged from 82% to 116% with RSDs between ±8% and ±12% and limits of detection below 1 mg/L except for IPBC. The optimized procedure was successfully applied for the determination of leather preservatives in eleven residual tanning floats taken from different companies. This method enables us to determine quantitatively the fungicides contained in the residual floats. Consequently, it will constitute a very useful tool to improve the preservative uptake in leather manufacturing processes. Note de contenu : - EXPERIMENTAL : Materials - Instrumentation - Samples - Procedure
- RESULTS AND DISCUSSION : Fiber choice and development of desorption conditions - Adsorption conditions - Validation (linearity - Recovery and precision - Limits of detection and limits of quantification - Robustness of calibration) - Analyses of real samplesEn ligne : https://drive.google.com/file/d/1wku4fCcOK1qCDxOmZpiH6SqkzGjpSOCP/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=17368
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CVIII, N° 2 (02/2013) . - p. 41-47[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 14610 - Périodique Bibliothèque principale Documentaires Disponible
Titre : Determination of TCMTB and other fungicides in leather Type de document : texte imprimé Auteurs : Joaquim Font, Auteur ; M. Reyes, Auteur ; Sara Cuadros, Auteur ; Anna Bacardit, Auteur ; Agusti Marsal, Auteur Année de publication : 2011 Article en page(s) : p. 341-348 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Antifongiques
Cuir
Thiocyano-méthylthiobenzotiazoleIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : The new ISO 13365:2011 develops a test method for the determination of the content of the preservative agents 2-(thiocyanomethylthio)-benzothiazole (TCMTB), 4-chloro-3-methylphenol (PCMC), 2-phenylphenol (OPP) and 2-Octyl-3(2H)-isothiazolone (OIT) in leather by liquid chromatography. The simultaneous determination of the fungicides TCMTB, PCMC, OPP, OIT, and also 2-mercaptobenzothiazol (MBT) and 3-iodo-2-propynyl-butylcarbamate (IPBC) in leather samples was carried out by liquid chromatography (HPLC) with diode array ultraviolet detection. The sample preparation and extraction step was performed following the new ISO 13365 Standard. The mobile phase was 0.1% formic acid in water (A) : 0.1% formic acid in acetonitrile (B). Gradient: 60% B, 6 min isocratic, then linear to 95% B in 9 min. The chromatographic detection introduced only a minor change with respect to the Standard: a photo diode array detector was used instead of a single wavelength ultraviolet one, thereby improving the reliability of the identifications and the sensitivity of the quantification. It has been ensured that 2,4,6-trichlorophenol (TCP) and pentachlorophenol (PCP) not interfere in the determination. The leather fortifications of 30 and 300 mg/kg yielded average TCMTB recoveries of 94% and 99%, respectively. The recoveries of the other fungicides were similar. The targeted fungicides were determined in 40 samples of commercial leather. Residues of TCMTB were found in 90% of samples. In summary, the new ISO 13365:2011 Standard provides a quick and reliable method not only for the determination of the four molecules that are within the scope of the Standard but also for other fungicides such as IPBC and MBT. Note de contenu : - EXPERIMENTAL : Instrumentation - Materials - Samples - Procedures
- RESULTS AND DISCUSSION : Limits of detection and quantification - Linearity, recovery and precision - Selection of wavelength of detection - Analysis of commercial samplesEn ligne : https://drive.google.com/file/d/19XjQ5s3y5T5kEoC4Y9iPRhX1M6Hvfu-4/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=12523
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CVI, N° 11 (11/2011) . - p. 341-348[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 13434 - Périodique Bibliothèque principale Documentaires Disponible
Titre : Inter-laboratory study on formaldehyde determination by HPLC Type de document : texte imprimé Auteurs : Joaquim Font, Auteur ; Agusti Marsal, Auteur ; Sara Cuadros, Auteur ; M. A. Juàrez, Auteur ; E. Verdù, Auteur ; M. Jorba, Auteur ; M. Reyes, Auteur ; T. Rius, Auteur ; S. Viera, Auteur Année de publication : 2008 Article en page(s) : p. 53 - 61 Note générale : Bibliogr. Langues : Américain (ame) Résumé : The colorimetric determination of formaldehyde in a water extract of a leather sample is a procedure that has been criticized because of possible interferences of other aldehydes and coloured substances that could interfere in the spectrophotometric detection. The measurement by liquid chromatography HPLC is an alternative method that was developed some years ago. This method is more sophisticated but more selective and free of the aforementioned interferences. It is not sensitive to coloured extracts. With the implementation of HPLC equipment in many laboratories, this choice has become feasible in our sector. The process is selective. Formaldehyde is separated and quantified as a derivative from other aldehydes and ketones by liquid chromatography. The free-formaldehyde and formaldehyde which is hydrolysed during extraction to yield free-formaldehyde are detected by this method. The sample is eluted with water at 40°C. The eluate is mixed with 2,4 dinitrophenylhydrazine, whereby aldehydes and ketones react to yield the respective hydrazones. These are separated by means of a reversed-phase HPLC method, detected at 350 nm and quantified. The aim of this work is to present a collaborative inter-laboratory study coordinated by the Igualada Leather Technology School and carried out with four other laboratories that had previously implemented the HPLC method or that were planning to do this. Determination of formaldehyde content in leather was carried out in each laboratory in accordance with prEN ISO 17226:2005 - HPLC Standard, developed by the Committee CEN/TC 289. Part 2 of the ISO 5725 Standard (Basic method for the determination of repeatability and reproducibility of a standard measurement method) was applied to examine the results. The study proved successful. The HPLC method achieved very reproducible results between laboratories. This work has also demonstrated that other aldehydes, glutaraldehyde included, do not interfere in the chromatographic method. The use of a PDA detector increases the confidence of the detection of formaldehyde in leather samples. En ligne : https://drive.google.com/file/d/1E16gTqYgL-Wrer6A0lzBSboae2jF1S61/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=2572
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CIII, N° 3 (02/2008) . - p. 53 - 61[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 009769 - Périodique Bibliothèque principale Documentaires Disponible
Titre : Recovery of organic nitrogen from beamhouse wastewater in a hair recovery process Type de document : texte imprimé Auteurs : Agusti Marsal, Auteur ; Joaquim Font, Auteur ; A. Rius, Auteur ; M. Reyes, Auteur ; Sara Cuadros, Auteur ; E. Bautista, Auteur Année de publication : 2009 Article en page(s) : p. 176-182 Note générale : Bibliogr. Langues : Anglais (eng) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : In the leather industry, in addition to the extrinsic contamination attribuable to chemical products not absorbed by the hides, there is intrinsic contamination produced by the hides themselves. from each 100 kgs of raw material, 15 kgs of solubilised protein will end up in wastewater in the early stages of the process of transforming hides into leather. These proteins contain nearly 18% of nitrogen. In this study it is proposed to recover organic nitrogen from the proteins present in the effluents of the beamhouse operations of hides and the subsequent revalorization of the protein fraction obtained.
This work seeks to characterize (the chemical oxigen demand (COD), total nitrogen, ammonium nitrogen, total soluble nitrogen, particulate nitrogen, organic nitrogen and protein) the wastewaters, individually or in groups, of the various beamhouse operations (soaking, unhairing-liming, washing, conditioning, deliming, bating, washing and pickling) with hair recovery.
The studies are presented of the determination of the pH value (adjusted by means of buffers of acetic acid/sodium acetate) at which the greatest precipitate of the protein fraction if produced. In addition, the following tests were performed to characterize these precipitates : determination of the quantitative composition of the main components of the protein fraction (humidity, proteins, free amino acids, fats and other matter soluble in dichloromethane and ash) ; heavy metals content, calcium, magnesium, potassium and sodium and the composition in total amino acids with prior acid hydrolysis of the protein fraction with 6N hydrochloric acid.En ligne : https://drive.google.com/file/d/15jtZl0drv7WDsFm3P8MYIps2ch5NYQcV/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=6276
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 93, N° 5 (09-10/2009) . - p. 176-182[article]Réservation
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