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NMR relaxometry analysis of molecular degradation in internal combustion engine lubricants
(John Wiley & Sons Ltd, 2021-04)
A set of experimental techniques headed by proton fast field-cycling nuclear magnetic resonance (1HFFC-NMR) were used to analyze the effects of degradation of lubricant oil used in an internal combustion engine (ICE). Its ...
Trap-Door-Like irreversible photoinduced charge transfer in a Donor-Acceptor Complex
(American Chemical Society, 2018-06)
For efficient conversion of light into useful energy sources, it is very important to study and describe the first steps of primary charge-transfer process in natural structures and artificial devices. The time scale of ...
Intermolecular interactions, spectroscopic and theoretical investigation of 4-aminoacetophenone
(Science Publishing Corporation, 2019-05)
The molecular structure of 4-aminoacetophenone (PAAP) was determined by DFT calculations using different basis sets. The structural parameters, electronic properties and vibrational wavenumbrers of the optimized geometry ...
Synthesis of 6,19-sulfamidate bridged pregnanes
(American Chemical Society, 2005-10)
Conformationally restrained substituted pregnane-20-one derivatives were obtained by an intramolecular nitrene addition onto a C-5/C-6 double bond involving a tethered C-19 sulfamoyl moiety. The resulting aziridine underwent ...
Isomerism and decoherence
(Springer, 2016-03)
In the present paper we address the problem of optical isomerism embodied in the socalled "Hund´s paradox", which points to the difficulty to account for chirality by means of quantum mechanics. In particular, we explain ...
Picomolar inhibitors of HIV-1 reverse transcriptase: Design and crystallography of naphthyl phenyl ethers
(American Chemical Society, 2014-11)
Catechol diethers that incorporate a 6-cyano-1-naphthyl substituent have been explored as non-nucleoside inhibitors of HIV-1 reverse transcriptase (NNRTIs). Promising compounds are reported that show midpicomolar activity ...
Computational predictions on the interactions of parabens with a dipalmitoyl phosphatidylcholine lipid bilayer and the human serum albumin protein
(Open Access Text, 2016-09)
Parabens are esters of para-hydroxybenzoic acid extensively used as preservatives in cosmetics and pharmaceutics. In the recent years their safe use has been questioned, mainly due to their estrogenic activity, their ...
Electron Donor-Acceptor Complexes in Perfluoroalkylation Reactions
(Wiley VCH Verlag, 2018-12)
Electron-donor-acceptor complexes (EDA) can be established through halogen-bonding interactions between the N lone electron pair from organic bases (or N-/O-centered anions) and perfluoroalkyl iodides RF–I. These EDA ...
Geographical and botanical classification of honeys and apicultural products by chemometric methods. A review
(Bentham Science Publishers, 2012-07)
Evaluations of adulteration, geographical and botanical origin of bee-products are matters of great interest worldwide. These trends are principally related to the international market of food commodities. The chemometric ...
Ultrasensitive detection of nitrogen oxides over a nanoporous membrane
(American Chemical Society, 2010-12)
A nitrogen oxide (NOx; x = 1, 2) optical sensor with an extremely low detection limit in the range of fractions of ppbV (0.3 ppbV for 20 s sample injection) is presented. Phenylenediamine derivatives are utilized as molecular ...