Publicaciones 2011-2020

@article{RN321,
title = {Protonation Sites, Tandem Mass Spectrometry and Computational Calculations of O-Carbonyl Carbazolequinone Derivatives},
author = { M. Martinez-Cifuentes and G. Clavijo-Allancan and P. Zuniga-Hormazabal and B. Aranda and A. Barriga and B. Weiss-Lopez and R. Araya-Maturana},
url = {/brokenurl#<Go to ISI>://WOS:000381500900086},
doi = {UNSP 1071, 10.3390/ijms17071071},
issn = {1422-0067},
year = {2016},
date = {2016-01-01},
journal = {International Journal of Molecular Sciences},
volume = {17},
number = {7},
abstract = {A series of a new type of tetracyclic carbazolequinones incorporating a carbonyl group at the ortho position relative to the quinone moiety was synthesized and analyzed by tandem electrospray ionization mass spectrometry (ESI/MS-MS), using Collision-Induced Dissociation (CID) to dissociate the protonated species. Theoretical parameters such as molecular electrostatic potential (MEP), local Fukui functions and local Parr function for electrophilic attack as well as proton affinity (PA) and gas phase basicity (GB), were used to explain the preferred protonation sites. Transition states of some main fragmentation routes were obtained and the energies calculated at density functional theory (DFT) B3LYP level were compared with the obtained by ab initio quadratic configuration interaction with single and double excitation (QCISD). The results are in accordance with the observed distribution of ions. The nature of the substituents in the aromatic ring has a notable impact on the fragmentation routes of the molecules.},
keywords = {antitumor assignment, basicities, c-13 carbazole, chemistry complete derivatives, dft, gas-phase hydroquinone ionization, mass molecules, nmr-spectra, qcisd, quinones, respiration, spectrometry, tumor-cell},
pubstate = {published},
tppubtype = {article}
}

@article{RN162,
title = {Comparative Measurements and Their Compliance with Standards of Total Mercury Analysis in Soil by Cold Vapour and Thermal Decomposition, Amalgamation and Atomic Absorption Spectrometry},
author = { M.A. Leiva and S. Morales and R. Segura},
url = {/brokenurl#<Go to ISI>://WOS:000315281300006},
doi = {10.1007/s11270-012-1390-3},
issn = {0049-6979},
year = {2013},
date = {2013-01-01},
journal = {Water Air and Soil Pollution},
volume = {224},
number = {2},
abstract = {Two methods to measure mercury concentration in soil are compared, and their compliance with international standards is determined: cold vapour atomic absorption spectrometry and thermal decomposition, amalgamation and atomic absorption spectrophotometry. The detection limit, quantification limit and uncertainty of these two analytical methods were evaluated and compared. The results indicated that thermal decomposition, amalgamation and atomic absorption spectrophotometry had a lower quantification limit and uncertainty than cold vapour atomic absorption spectrometry (quantification limit, 0.27 vs. 0.63 mg kg(-1); expanded uncertainty, 9.30 % vs. 10.8 %, respectively). Thermal decomposition, amalgamation and atomic absorption spectrophotometry allowed the determination of the base values for the concentration of mercury in soil recommended by international standards, achieving a lower detection limit than cold vapour atomic absorption spectrometry under the study conditions. In addition, thermal decomposition, amalgamation and atomic absorption spectrophotometry represent a more environmentally friendly alternative for mercury determination because this method uses fewer reagents and therefore generates less waste.},
keywords = {compliance, emissions, environmental chemistry, fish, fluorescence impact, in measurement mercury samples, sediments, soil, spectrometry, standards uncertainty, validation},
pubstate = {published},
tppubtype = {article}
}