Search results for " radical"
showing 10 items of 757 documents
The effect of chlorine substituent(s) on the primary loss of a methyl radical from chlorinated veratroles (1,2-dimethoxybenzenes)
1989
Versuche zum Vorgang der Wasserstoffübertragung, XI. Isomerisierung Definiert Deuterierter Alkylbenzole an Raney-Nickel
1964
α-Deutero-toluol. o-, m- und p-Deutero-toluol sowie β-Deutero-athylbenzol isomerisieren schon bei 20° in Beruhrung mit wasserfreiem Raney-Nickel. Der Deuterium-Gehalt des Substrates bleibt dabei annahernd konstant. Beim α-Deutero-toluol wandern mehr als 50% des Deuteriums aus der Seitenkette in den Kern, wobei es sich weitgehend auf die gleichen Positionen verteilt wie beim Austausch von leichtem Toluol mit Deuterium-Gas an Raney-Nickel. Der aromatische Kern wird unter diesen Bedingungen nicht abgesattigt. Mit Hilfe der Massenspektrographie kann gezeigt werden, das Deuterium auch zwischenmolekular ausgetauscht wird. — Im Toluol kernstandiges Deuterium verteilt sich an Raney-Nickel auf samtl…
[39] DNA damage induced by ultraviolet and visible light and its wavelength dependence
2000
Publisher Summary DNA damage induced by solar radiation in mammalian cells consists largely of two types of modification: pyrimidine dimers and oxidative modifications. Pyrimidine dimmers that can be subdivided into cyclobutane pyrimidine dimmers, (CPDs) and (6-4) photoproducts are the characteristic and most abundant modifications after direct excitation of DNA, although they can also be formed indirectly by energy transfer from other excited molecules such as carbonyl compounds. Oxidative DNA damage, which includes various pyrimidine and purine modifications, sites of base loss (AP sites), and strand breaks, is generated in only low yield after direct excitation of DNA (except at very sho…
Hydroxyl Radical Addition to Thymine and Cytosine and Photochemistry of the Adducts at the C6 Position
2019
Modellazione eco-idrologica del ruolo delle radici nell'analisi di stabilità di un versante
2014
Inappropriabilità, improprietà, produzione. Il comune, un'introduzione
2021
Si tratta di una ricostruzione del modo in cui il concetto di "comune" è stato usato nel pensiero radicale degli ultimi anni. The essay reconstructs the way in wich the concept of common has been used in radical thinking in recent years.
Increased conformational rigidity of humic substances by oxidative biomimetic catalysis
2005
A synthetic water-soluble meso-tetra(2,6-dichloro-3-sulfonatophenyl)porphyrinate of iron(III) chloride, Fe(TDCPPS)Cl, was employed as a biomimetic catalyst in the oxidative coupling of terrestrial humic materials. High-performance size-exclusion chromatography (HPSEC), solid-state nuclear magnetic resonance (CPMAS-(13)C NMR), electron paramagnetic resonance (EPR), and diffuse reflectance infrared spectroscopy (DRIFT) were used to follow conformational and structural changes brought about in different humic materials by the oxidative coupling. Increase in apparent weight-average molecular weight (Mw(a)) occurred invariably for all humic substances with the oxidative polymerization catalyzed …
Synthesis of 3-alkyl-4-(cholomethyl)-1-RSO2-1-H-pyrrol-2-(5H)ones, using a sequential ATCR/[1,2] elimination, from 2,2-dichloro-N-(2-chloroallyl)-N-R…
2011
Gas phase behavior of radical cations of perfluoroalkyl-1,2,4-triazines: an experimental and theoretical study
2009
Electron ionization mass spectrometry and low-energy collision-induced decomposition reactions occurring in a tridimensional ion trap, together with density functional theory (DFT) calculations on neutrals, even- and odd-electron cations, have been used to study the gas-phase ion chemistry of a series of perfluoroalkyl-1,2,4-triazines. Loss of oxygen, due to thermal degradation occurring before ionization, likely involving the hydroxylamino group, has been observed. Compounds having a carbonyl group at position 6 of the triazine ring fragment in the source by elimination of NO followed by HF or CO. The decomposition pathways occurring due to CID experiments have shown interesting features d…
The Importance of Electronic Dimensionality in Multiorbital Radical Conductors
2019
The exceptional performance of oxobenzene-bridged bis-1,2,3-dithiazolyls 6 as single-component neutral radical conductors arises from the presence of a low-lying π-lowest unoccupied molecular orbital, which reduces the potential barrier to charge transport and increases the kinetic stabilization energy of the metallic state. As part of ongoing efforts to modify the solid-state structures and transport properties of these so-called multiorbital materials, we report the preparation and characterization of the acetoxy, methoxy, and thiomethyl derivatives 6 (R = OAc, OMe, SMe). The crystal structures are based on ribbonlike arrays of radicals laced together by S···N′ and S···O′ secondary bondin…