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1.
Esther Domínguez Concepción Laborra Aranzazu Linaza Ana Madoz Issa A. Katime 《Monatshefte für Chemie / Chemical Monthly》1989,120(8-9):743-748
Summary A series of mono and diesters of itaconic acid containing alkoxy and sulfide side chains of variable lengths has been synthesized. Their structures have been established on the basis of their spectral data.
Eine Serie von Mono- und Diestern von Itaconsäure: Synthese und Strukturbestimmung
Zusammenfassung Es wurde eine Serie von Mono- und Diestern von Itaconsäure mit Alkoxy- und Sulfidseitenketten variabler Länge synthetisiert. Die Strukturaufklärung erfolgte mittels spektroskopischer Daten.相似文献
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Silvia Millán M. Carmen Sampedro Patricia Gallejones Ander Castellón Maria L. Ibargoitia M. Aranzazu Goicolea Ramón J. Barrio 《Analytical and bioanalytical chemistry》2009,394(6):1661-1669
A rapid and sensitive method for the speciation and quantification of glucosinolates in rapeseed is described. The method
combines liquid chromatography (LC) with ion trap mass spectrometry (ITMS) detection. Electrospray ionization (ESI) has been
chosen as the ionization technique for the on-line coupling of LC with ITMS. Glucosinolates are extracted from different rapeseeds
with MeOH and the extracts are cleaned-up by solid phase extraction with Florisil cartridges. Aqueous extracts are injected
into LC system coupled to an ITMS, leading to accurately quantify eight of the most important glucosinolates in rapeseed,
by MS2 mode and confirming their structure by MS3 acquisition. All the glucosinolates found in rapeseeds provide good signals corresponding to the deprotonated precursor ion
[M-H]−. The method is reliable and reproducible, and detection limits range from 0.5 nmol g−1 to 3.7 nmol g−1 when 200 mg of dried seeds of certified reference material are analyzed. Within-day and between-day RSD percentages range
between 2.4–14.1% and 3.9–16.9%, respectively. The LC-ESI-ITMS-MS method described here allows for a rapid assessment of these
metabolites in rapeseed without a desulfatation step. The overall process has been successfully applied to identify and quantify
glucosinolates in rapeseed samples. 相似文献
3.
Sánchez A Millán S Sampedro MC Unceta N Rodríguez E Goicolea MA Barrio RJ 《Journal of chromatography. A》2008,1177(1):170-174
A sensitive and specific method for determining fenitrothion and its main metabolites, 3-methyl-4-nitrophenol and fenitrooxon, in poplar leaves using deuterated isotopes as the internal standard is described. The analytes and the labeled isotopes were extracted from leaves by solid-phase microextraction and subsequently analysed by gas chromatography coupled with mass spectrometry. The method had a chromatographic run time of 17.0 min and good linearity over the range 0.01-10 mg kg(-1). The detection limits ranged between 2.5 and 0.6 microg kg(-1). The isotopic dilution technique allowed improving significantly the repetitivity even using different fibers with the same coating (RSD<5.1%). The method was applied successfully to study the persistence of fenitrothion in forestal matrices in a poplar forest after cannon spray application of the insecticide. 相似文献
4.
A rapid liquid chromatographic-electrospray ionisation ion trap mass spectrometry (LC-ESI-ITMS) method has been developed for the routine analysis of eight of the most oenologically important biogenic amines in wine without any sample pre-treatment. The method involves addition of heptylamine as an internal standard (IS) and the direct injection of filtered wine samples previously diluted with ultra high purity (UHP) water. The full-scan MS-MS spectra and the identical retention times to those of reference standards were used for unequivocal identification of the analytes. For most amines, the most abundant ions were derived from the loss of an ammonia group, while in the case of spermine and the I.S. the major product ions arose from the loss of 1,3-propyldiamine and the production of adduct with water, respectively. Detection was achieved in positive ionisation with an ion trap mass spectrometer operating in multiple-reaction monitoring (MRM) mode. The method allowed accurate determination of the analytes in the range 0.5-40 ng mL−1. Within-day and between-day relative standard deviation percentages were <8% and <12%, respectively. The overall process was successfully applied to identify and quantify biogenic amines in Rioja red wines. The new method is sensitive, rapid, cheap and less labour intensive. 相似文献
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Ana Erica Paramo Susana Palmero Aranzazu Heras Alvaro Colina David Ibañez 《Electroanalysis》2016,28(4):890-897
The purpose of this work is to develop simple and reproducible ways to fabricate carbon nanofibers (CNFs) electrodes. Disposable CNFs electrodes were fabricated after filtering CNFs through polytetrafluoroethylene filters (PTFE), using directly as electrodes these filters with the CNFs film. The electrochemical behaviour of CNFs/PTFE electrodes were tested with ferrocenemethanol and tris(2,2′‐bypyridyl)dichlororuthenium(II) (Ru(bipy)32+). As a proof of concept of the analytical usefulness of the CNFs/PFTE electrodes, the study of vitamin B12 was carried out. Multivariate calibrate has been successfully used to determine vitamin B12 in a complex medium with vitamins B1 and B6 as interferents. 相似文献
8.
de la Riva H Pintado-Alba A Nieuwenhuyzen M Hardacre C Lagunas MC 《Chemical communications (Cambridge, England)》2005,(39):4970-4972
EXAFS has been used to directly show the existence of Au...Au interactions in dissolved Au(I) complexes for the first time; the information has been used to understand the optical properties of these materials. 相似文献
9.
Olatz Baroja M. Aranzazu Goicolea M. Carmen Sampedro Esther Rodríguez Zuriñe Gómez De Balugera Andrés Alonso 《International journal of environmental analytical chemistry》2013,93(5):341-353
Three solid adsorbents (Carbotrap, Carbotrap C, and Carbosieve III) were evaluated for sampling trace non-methane hydrocarbons in urban atmospheres. The sampled atmosphere was pumped through a multisorbent tube containing the three sorbents separated by a small amount of silanized glass wool. The trapped compounds were recovered by thermal desorption and analysed by combining cryogenic enrichment with gas chromatography and mass spectrometry. Adsorption/thermal desorption and breakthrough experiments were performed to test their ability to quantitatively trap the light hydrocarbons. The technique was suitable for determination of low ppbv concentrations of these compounds. Ambient atmospheric sampling was conducted in Vitoria-Gasteiz (Basque Country, Spain), and the measurements cover a period of one year (2001–2002). Fifteen C2–C6 hydrocarbons are identified and quantified, and seasonal trends are discussed. 相似文献
10.
M. Carmen Sampedro M. Aranzazu Goicolea Nora Unceta Alicia Sánchez‐Ortega Ramón J. Barrio 《Journal of separation science》2009,32(20):3449-3456
A method based on sequential stir bar sorptive extraction followed by automated thermal desorption–GC–MS for the determination of pesticides in underground and superficial water samples has been developed. Retention time locked GC–MS and deconvolution Automated Mass Spectral Deconvolution and Identification System software allows the use of pesticide databases for identification and quantification in routine applications. Quantitation limits and repetitivity using full scan mass spectrometric determination guarantee the applicability of the method, which enables considerable savings to be made in total analysis time, with data processing times of around 2 min/sample. 相似文献