Search results for "bromi"

Short X···N Halogen Bonds With Hexamethylenetetraamine as the Acceptor

2021

Hexamethylenetetramine (HMTA) and N-haloimides form two types of short (imide)X···N and X–X···N (X = Br, I) halogen bonds. Nucleophilic substitution or ligand-exchange reaction on the peripheral X of X–X···N with the chloride of N-chlorosuccinimide lead to Cl–X···N halogen-bonded complexes. The 1:1 complexation of HMTA and ICl manifests the shortest I···N halogen bond [2.272(5) Å] yet reported for an HMTA acceptor. Two halogen-bonded organic frameworks are prepared using 1:4 molar ratio of HMTA and N-bromosuccinimide, each with a distinct channel shape, one possessing oval and the other square grid. The variations in channel shapes are due to tridentate and tetradentate (imide)Br···N coordi…

CCDC 177642: Experimental Crystal Structure Determination

2002

Related Article: M.I.Burguete, M.Bolte, J.C.Frias, E.Garcia-Espana, S.V.Luis, J.F.Miravet|2002|Tetrahedron|58|4179|doi:10.1016/S0040-4020(02)00381-2

CCDC 1481997: Experimental Crystal Structure Determination

2016

Related Article: Fangfang Pan, Ngong Kodiah Beyeh, Robin H. A. Ras, Kari Rissanen|2016|CrystEngComm|18|5724|doi:10.1039/C6CE01229A

Fibromialgia: relación entre el estrés crónico, depresión, procesos inflamatorios y dolor.

2015

Por el término Fibromialgia (FM), asumimos un trastorno de etiología no conocida hasta el momento, aparentemente crónico, que se caracteriza por dolor muscular y articular generalizado incluyendo hipersensibilidad a numerosos estímulos como la presión, el frio o el calor. En la actualidad, la propia definición del cuadro, sus criterios diagnósticos y su etiopatogenia siguen siendo causa de debate. En los últimos años han ido apareciendo en la literatura numerosas hipótesis sobre el proceso de desarrollo de la FM que, aunque siguen aparentemente un patrón opuesto no se puede descartar que sean complementarias y se retroalimenten. En nuestro estudio nos hemos centrado en las hipótesis basadas…

CCDC 745351: Experimental Crystal Structure Determination

2011

Related Article: M.Albrecht, M.Muller, A.Valkonen, K.Rissanen|2010|CrystEngComm|12|3698|doi:10.1039/c003636f

Halogen activation in the plume of Masaya volcano: field observations and box model investigations

2020

Volcanic emissions are a source of halogens in the atmosphere. Rapid reactions convert the initially emitted hydrogen halides (HCl, HBr, and HI) into reactive species such as BrO, Br2, BrCl, ClO, OClO, and IO. The activation reaction mechanisms in the plume consume ozone (O3), which is entrained by ambient air that is mixed into the plume. In this study, we present observations of the oxidation of bromine, chlorine, and iodine during the first 11 min following emission, examining the plume from Santiago crater of the Masaya volcano in Nicaragua. Two field campaigns were conducted: one in July 2016 and one in September 2016. The sum of the reactive species of each halogen was determined by g…

FTIR quantitative analysis of calcium carbonate (calcite) and silica (quartz) mixtures using the constant ratio method. Application to geological sam…

2002

A methodology for quantifying calcium carbonate (875 and 712 cm(-1)) and silica (798 and 779 cm(-1)) by FTIR spectroscopy applying the constant ratio method is proposed. The studied method is applied for quantitative analysis of calcite and quartz in geological samples. The suggested method uses potassium ferricyanide (2115 cm(-1)) as standard and samples are prepared as potassium bromide pellets, with statistically satisfactory results (relative standard deviation less than 5%). The influence of particle size (pulverised samples) on the accuracy of the results found by FTIR spectroscopy applying the constant ratio method has been studied. The granulometric study suggests that the homogenei…

Functional Profile Of Aclidinium Bromide In Isolated Human Bronchi And Left Atria

2011

Multi-Arm Star Polyglycerol-block-poly(tert-butyl acrylate) and the Respective Multi-Arm Poly(acrylic acid) Stars

2006

Well-defined multi-arm star block copolymers, polyglycerol-block-poly(tert-butyl acrylate) (PG-b-PtBA), with average arm-numbers of 17, 27, 36, 66 and 90 arms, respectively, have been prepared by atom transfer radical polymerization (ATRP) of tBA in acetone, using a core-first strategy. After hydrolysis with excess concentrated HCl in refluxing dioxane, full hydrolysis of the tert-butyl ester groups was achieved, resulting in multi-arm star polyelectrolytes, polyglycerol-block-poly(acrylic acid) (PG-b-PAA). The hyperbranched macroinitiators employed were prepared on the basis of hyperbranched polyglycerols via esterification with 2-bromoisobutyryl bromide. Both CuBr/PMDETA and CuBr/Me 6 TRE…

Potential of phosphonium-based ionic liquids to purify 1-propanol from water by liquid–liquid extraction at mild conditions

2022

Abstract In order to reduce the environmental of the separation of 1-propanol from water in a residual industry stream for its reuse, the capability as solvents of two different trihexyl(tetradecyl)phosphonium ionic liquids (ILs) – trihexyl(tetradecyl)phosphonium chloride ([TDTHP][Cl]) and trihexyl(tetradecyl)phosphonium bromide ([TDTHP][Br])-, was studied. The liquid–liquid equilibria data for both ternary systems, {water + 1-propanol + [TDTHP][Cl]} and {water + 1-propanol + [TDTHP][Br]} at different mild work temperatures, (283.2, 303.2 and 323.2) K, and atmospheric pressure were measured. The thermodynamic parameters for both ternary systems at different work conditions were obtained by …