Search results for "Bromide"

Heat capacities, volumes and solubilities of pentanol in aqueous surfactant solutions

1989

Apparent molar heat capacities and volumes of pentanol (PentOH) 0.05m in dodecyltrimethylammonium chloride (DTAC), dodecyldimethylammonium chloride (DDAC) and dodecylamine hydrochloride (DAC) micellar solutions were measured at 25°C. They were assumed to approach the standard infinite dilution values and rationalized by means of previously reported equations. The distribution constant between the aqueous and the micellar phase and heat capacity and volume of pentanol in both phases were thus derived. The results show that the presence of methyl groups on the surfactant head group does not appreciably influence the apparent molar volume and heat capacity of pentanol in micellar phase and the…

1995

About 340 g of a cycloaliphatic ionene (see formula given in the introduction) were fractionated by a continuous countercurrent extraction method (CPF). The efficiency of the separation was checked by viscometry and gel permeation chromatography (GPC). Ten different fractions with number average molecular masses between 16 000 and 29 000 D were obtained and their glass transition temperatures T g determined by differential scanning calorimetry (DSC) for their bromide and tetrafluoroborate salts. No molecular weight dependence of T g was found, in contrast to recently reported results with aliphatic ionenes, where - in case of the bromide - T g increases with rising molecular weight.

On the origin of controlled anisotropic growth of monodisperse gold nanobipyramids

2021

We elucidate the crucial role of the cetyl trimethylammonium bromide (CTAB) surfactant in the anisotropic growth mechanism of gold nano-bipyramids, nano-objects with remarkable optical properties and high tunability. Atomistic molecular dynamics simulations predict different surface coverages of the CTAB (positively charged) heads and their (bromide) counterions as function of the gold exposed surfaces. High concentration of CTAB surfactant promotes formation of gold nanograins in solution that work as precursors for the smooth anisotropic growth of more elongated nano-bipyramidal objects. Nanobipyramids feature higher index facets with respect to nanorods, allowing higher CTAB coverages th…

CCDC 1005277: Experimental Crystal Structure Determination

2014

Related Article: Michael Giese, Markus Albrecht, Arto Valkonen, Kari Rissanen|2015|Chemical Science|6|354|doi:10.1039/C4SC02762K

CCDC 745349: Experimental Crystal Structure Determination

2011

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

CCDC 1005272: Experimental Crystal Structure Determination

2014

Related Article: Michael Giese, Markus Albrecht, Arto Valkonen, Kari Rissanen|2015|Chemical Science|6|354|doi:10.1039/C4SC02762K

CCDC 1005271: Experimental Crystal Structure Determination

2014

Related Article: Michael Giese, Markus Albrecht, Arto Valkonen, Kari Rissanen|2015|Chemical Science|6|354|doi:10.1039/C4SC02762K

Nanohydrogel Formation within the Halloysite Lumen for Triggered and Sustained Release

2018

An easy strategy to obtain nanohydrogels within the halloysite nanotube (HNTs) lumen was investigated. Inorganic reverse micelles based on HNTs and hexadecyltrimethylammonium bromides were dispersed in chloroform, and the hydrophilic cavity was used as a nanoreactor to confine the gel formation based on alginate cross-linked by calcium ions. Spectroscopy and electron microscopy experiments proved the confinement of the polymer into the HNT lumen and the formation of calcium-mediated networks. Biological tests proved the biocompatibility of the hybrid hydrogel. The nanogel in HNTs was suitable for drug loading and sustained release with the opportunity of triggered burst release by chemical …

4,5-Disubstituted 1-Methylimidazoles via Cyclization of Defined α-Aminoketones: Synthesis of Fungerin and Analogues I

2016

A protocol for the chemoselective synthesis of the fungal metabolite fungerin has been developed. First the required N-methyl α-aminoketone was generated starting from sarcosine, propiolic acid, and prenyl bromide. Marckwald thioimidazole cyclization and subsequent sulfur removal delivered the target fungerin as well as an analogue, respectively, displaying defined substitution patterns.

Predictive Toxicology of Cobalt Nanoparticles and Ions: Comparative In Vitro Study of Different Cellular Models Using Methods of Knowledge Discovery …

2011

The toxicological effects of cobalt nanoparticles (Co-NPs) aggregates were examined and compared with those of cobalt ions (Co-ions) using six different cell lines representing lung, liver, kidney, intestine, and the immune system. Dose-response curves were studied in the concentration range of 0.05-1.0 mM, employing 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide test, neutral red, and Alamar blue as end point assays following exposures for 48 and 72 h. Data analysis and predictive modeling of the obtained data sets were executed by employing a decision tree model (J48), where training and validation were carried out by an iterative process. It was established, as expected, th…