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991.
Claudia Conti Jana Striova Irene Aliatis Chiara Colombo Marinella Greco Elena Possenti Marco Realini Luigi Brambilla Giuseppe Zerbi 《Analytical and bioanalytical chemistry》2013,405(5):1733-1741
This study aims to evaluate the relevance of portable Raman and portable mid-Fourier transform infrared (FTIR) reflectance instruments in monitoring the synthetic treatments applied on plaster substrates, a crucial issue in a conservation work. Some polymeric consolidants and protectives have a relatively short life owing to their degradation, and after some years the surface should be retreated. It follows that any information about the presence and composition of the products applied, their chemical transformations and their distribution on the surfaces is essential. For these purposes, conservation scientists should seek and test new in situ methods, and this is of utmost importance especially in the case of buildings, considering their large dimensions and consequent extensive mapping. The effectiveness of portable Raman and portable mid-FTIR reflectance instruments has been compared by analysing a set of laboratory specimens prepared and treated with variable amounts of products belonging to three classes of polymers; the spectroscopic investigation highlighted, for the first time, the limits and the advantages of portable Raman and portable mid-FTIR reflectance instruments in the detection of small amounts of products commonly employed for the conservation of plasters. 相似文献
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Nicoletti Marcello Toniolo Chiara Gallo Francesca Romana Multari Giuseppina Palazzino Giovanna 《平面色谱法杂志一现代薄层色谱法》2013,26(3):243-247
JPC – Journal of Planar Chromatography – Modern TLC - A high-performance thin-layer chromatography (HPTLC) method was developed for simple and rapid chemical analyses of... 相似文献
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Tomas Drevinskas Rūta Mickienė Audrius Maruška Mantas Stankevičius Nicola Tiso Jurgita Mikašauskaitė Ona Ragažinskienė Donatas Levišauskas Violeta Bartkuvienė Vilija Snieškienė Antanina Stankevičienė Chiara Polcaro Emanuela Galli Enrica Donati Tomas Tekorius Olga Kornyšova Vilma Kaškonienė 《Analytical and bioanalytical chemistry》2016,408(4):1043-1053
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GC-MS analytical methods for the determination of personal-care products in water matrices 总被引:1,自引:0,他引:1
Maria Chiara Pietrogrande Giulia Basaglia 《Trends in analytical chemistry : TRAC》2007,26(11):1086-1094
This article discusses the more recent methods combining gas chromatography and mass spectrometry (GC-MS) for analysis of personal-care products (PCPs) in water matrices. We describe different procedures for sample extraction and preparation as well as different instrumental methods commonly used for these compounds. GC-MS and GC-tandem MS (GC-MS2), which are complementary to liquid chromatography combined with MS (LC-MS), allow identification and quantification of PCPs belonging to different classes with the sensitivity and the selectivity necessary for environmental monitoring. The compounds investigated include fragrances (e.g., nitro and polycyclic musks), antimicrobial compounds (e.g., triclosan), ultraviolet blockers (e.g., methylbenzylidene camphor), antioxidants and preservatives (e.g., phenols and p-hydroxybenzoic acid (parabens)) and insect repellents (e.g., N,N-diethyl-m-toluamide (DEET)). We critically review data in the literature by focusing attention on analytical methods devoted to simultaneous detection and quantification of structurally diverse pharmaceuticals and PCPs. 相似文献
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Vitamin C: an experimental and theoretical study on the gas‐phase structure and ion energetics of protonated ascorbic acid 下载免费PDF全文
Andreina Ricci Federico Pepi Paola Cimino Anna Troiani Stefania Garzoli Chiara Salvitti Brunella Di Rienzo Vincenzo Barone 《Journal of mass spectrometry : JMS》2016,51(12):1146-1151
In order to investigate the gas‐phase mechanisms of the acid catalyzed degradation of ascorbic acid (AA) to furan, we undertook a mass spectrometric (ESI/TQ/MS) and theoretical investigation at the B3LYP/6‐31 + G(d,p) level of theory. The gaseous reactant species, the protonated AA, [C6H8O6]H+, were generated by electrospray ionization of a 10?3 M H2O/CH3OH (1 : 1) AA solution. In order to structurally characterize the gaseous [C6H8O6]H+ ionic reactants, we estimated the proton affinity and the gas‐phase basicity of AA by the extended Cooks's kinetic method and by computational methods at the B3LYP/6‐31 + G(d,p) level of theory. As expected, computational results identify the carbonyl oxygen atom (O2) of AA as the preferred protonation site. From the experimental proton affinity of 875.0 ± 12 kJ mol?1 and protonation entropy ΔSp 108.9 ± 2 J mol?1 K?1, a gas‐phase basicity value of AA of 842.5 ± 12 kJ mol?1 at 298 K was obtained, which is in agreement with the value issuing from quantum mechanical computations. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献