Search results for "Bromine"
showing 10 items of 102 documents
Role of Hydroxyl, Superoxide, and Nitrate Radicals on the Fate of Bromide Ions in Photocatalytic TiO2 Suspensions
2020
The influence of bromide ions on systems containing highly reactive radical species is of great interest for environmental remediation, atmospheric chemistry, and the synthesis of high-added-value ...
Isomeric Yield Ratios of 134I and 136I and Independent Fractional Yields of some Halogen Isotopes in the Fission of 232Th with Reactor Neutrons
1990
Polyphenols, methylxanthines, fatty acids and minerals in cocoa beans and cocoa products
2019
In this study, the nutritional profile and some health benefit of three cocoa bean samples of different origins, including Perù, Ecuador (Criollo) and Ghana (Hybrid) and five samples of cocoa products from Criollo variety at different percentage of cocoa solids (from 70 to 100%), are investigated. The Ecuadorian beans were of the same batch used to obtain the chocolate samples (70% cocoa solids) by processing without conching. All samples were analyzed for their proximate composition, mineral content, fatty acids, total polyphenols, catechin, epicathechin theobromine and caffeine. Fatty acid profiles of the cocoa products were quite similar to those obtained in cocoa beans. The atherogenici…
Evaluation of the environmental impact of volcanic emissions from the chemistry of rainwater: Mount Etna area (Sicily)
2001
Abstract The S, halogen and NO 3 contents of rainwater samples from the Etnean area were studied in order to define the environmental impact of plume emissions on the local environment. Samples, collected on a network of 11 bulk rain gauges, show significant variability in anion content, which can be ascribed to different meteorological and environmental conditions at each sampling site and to a variable distance from the different source areas. Data analysis suggests that S, F, Cl and Br are mainly magma-derived, whereas NO 3 mainly originates from anthropogenic sources. Samples collected from sites close to craters display considerable temporal variability, with increased anion concentrat…
Nucleophilic reactions in the indole series: displacement of bromine under phase transfer catalysis
2008
A novel synthetic approach for the synthesis of 3-substituted indoles by nucleophilic substitution of 3-bromo derivatives under phase transfer catalysis (PTC) was reported.
Green synthesis of bromine by TiO2 heterogeneous photocatalysis and/or ozone: A kinetic study
2018
Abstract Elemental bromine is an industrially relevant compound traditionally produced from bromide ions by using chlorine as the oxidizing agent. Problems related to transportation and handling of the corrosive, expensive and toxic chlorine make green synthetic alternatives highly desirable. In this paper the green synthesis of bromine from bromide in aqueous solutions under mild conditions by means of TiO2 photocatalysis and/or ozonation has been investigated from a kinetic point of view. The ozonation in the absence of the photocatalyst follows a first order kinetic with respect to both ozone and bromide. The kinetics of the reactions in the presence of the photocatalyst has been describ…
Phosphoraneiminato complexes of manganese and cobalt with heterocubane structure
1999
The phosphoraneiminato complexes [MnBr(NPEt3)]4 (1) and [M4Br5{NP(NMe2)3}3] with M = Mn (2) and M = Co (3) are prepared by melting reactions from the anhydrous metal dibromides with the silylated phosphaneimines Me3SiNPR3 (R = Et, NMe2) in the presence of potassium fluoride. All complexes are characterized by crystal structure analyses. 1 forms an only slightly distorted Mn4N4 heterocubane skeleton with an approximate Td symmetry and short Mn…Mn distances of average 295.7 pm. In the structures of 2 and 3 one μ3-NPEt3 ligand of 1 is replaced by one bromine atom with μ3-function. This leads to the novel heterocubane type M4N3Br with approximate C3 symmetry. The deformation of the cubic skelet…
Inhibitory responses to exogenous adenosine in murine proximal and distal colon”
2006
The aims of the present study were firstly, to characterize pharmacologically the subtypes of P(1) purinoreceptors involved in the inhibitory effects induced by exogenous adenosine in longitudinal smooth muscle of mouse colon, and secondly, to examine differences in the function and distribution of these receptors between proximal and distal colon. Adenosine (100 microM-3 mM) caused a concentration-dependent reduction of the amplitude of spontaneous contractions in the proximal colon, and muscular relaxation in the distal colon. In the proximal colon, adenosine effects were antagonized by a selective A(1) receptor antagonist, 1,3-dipropyl-8-cyclopentylxanthine (DPCPX, 10 nM), but were not m…
The potential link between episodes of diverticulitis or hemorrhoidal proctitis and diets with selected plant foods : a case-control study
2021
Diverticulitis and hemorrhoidal proctitis in the population are significant public health problems. We studied the potential association between the intake of certain plant foods and diverticulitis or hemorrhoidal episodes through a case–control study including 410 cases and 401 controls. We used a semiquantitative food frequency questionnaire. The intake was additionally quantified according to a 24 h recall. The plant foods or derived food products were categorized by their main chemical components into ethanol, caffeine/theine/theobromine, capsaicin, alliin, acids, eugenol, and miscellaneous foods such as curcumin. The mean score for overall intake of plant foods under consideration was …
A metabolomics-driven approach to predict cocoa product consumption by designing a multimetabolite biomarker model in free-living subjects from the P…
2014
Scope The aim of the current study was to apply an untargeted metabolomics strategy to characterize a model of cocoa intake biomarkers in a free-living population. Methods and results An untargeted HPLC-q-ToF-MS based metabolomics approach was applied to human urine from 32 consumers of cocoa or derived products (CC) and 32 matched control subjects with no consumption of cocoa products (NC). The multivariate statistical analysis (OSC-PLS-DA) showed clear differences between CC and NC groups. The discriminant biomarkers identified were mainly related to the metabolic pathways of theobromine and polyphenols, as well as to cocoa processing. Consumption of cocoa products was also associated wit…