Search results for "Lithium bromide"
showing 7 items of 7 documents
Deprotonation of Benzoxazole and Oxazole Using Lithium Magnesates
2005
International audience; The first deprotonations of oxazole and benzoxazole using lithium magnesates are described. The reactions occurred in tetrahydrofuran at room temperature using 1/3 equiv of lithium tributylmagnesate. As 2-lithiooxazole and 2-lithiobenzoxazole, lithium tri(2-oxazolyl)magnesate and lithium tri(2-benzoxazolyl)magnesate very rapidly and completely isomerized to the more stable 2-(isocyano)enolate and 2-(isocyano)phenolate type structures, respectively, a result shown by NMR analysis. The isolation of 2-substituted oxazoles and benzoxazoles in medium to good yields after electrophilic trapping was interpreted in two ways: (1) the equilibration between the open and closed…
Online Visualization of Corrosion Processes of Zinc and a Cu/Zn Galvanic Pair in Lithium Bromide Solutions
2003
Abstract A new method has been developed for online visualization of corrosion processes. The system allows surface images of the tested electrode to be captured simultaneously with the recorded electrochemical signal caused by corrosion processes without disturbing the electrochemical system. The experimental device consists of an electrochemical system with a horizontal electrochemical cell coupled to optical equipment. The horizontal position of the electrodes tested permitted the direct observation of surface modifications with time and of the experimental conditions by means of a triocular microscope stereoscope assembled to an image acquisition system. The new methodology was applied …
Water vapour pressure above saturated salt solutions at low temperatures
1999
Abstract The properties of water–salt systems in relation to their vapour pressure are studied especially at low temperature. The water vapour pressure of saturated salt solutions of strontium chloride, zinc chloride, nickel chloride, nickel nitrate, magnesium chloride, magnesium bromide, magnesium nitrate, calcium chloride, potassium nitrite, lithium chloride, lithium bromide, lithium iodide and sodium bromide are measured in a temperature range −40 to +10°C. The apparatus used in this study, is well adapted to measure very low pressure with an uncertainty of pressure measurement of 2% for a range between 10−3 and 10 mm Hg. The experimental values are fitted by Antoine equation with mean p…
Effect of alloying elements on the electronic properties of thin passive films formed on carbon steel, ferritic and austenitic stainless steels in a …
2014
The influence of alloying elements on the electrochemical and semiconducting properties of thin passive films formed on several steels (carbon steel, ferritic and austenitic stainless steels) has been studied in a highly concentrated lithium bromide (LiBr) solution at 25 °C, by means of potentiodynamic tests and Mott Schottky analysis. The addition of Cr to carbon steel promoted the formation of a p-type semiconducting region in the passive film. A high Ni contentmodified the electronic behaviour of highly alloyed austenitic stainless steels.Mo did notmodify the electronic structure of the passive films, but reduced the concentration of defects.
The glass transition behaviour of salted nylon 6
1981
Glass transition measurements of nylon-6/lithium halides mixtures have been carried out in wide range of frequency with the aid of different experimental techniques. The results show an increase of the glass transition temperature when the salt is present and prove the larger effectiveness of lithium chloride with respect of lithium bromide. This effect, in line with the large reduction of the specific volume caused by the salt, is due to the formation of a pseudo-cross-linking between lithium ions and the carbonyl-oxygen groups of the polyamide.
ChemInform Abstract: Remarkable Effect of Lithium Bromide in the Enantioselective Protonation with α-Sulfinyl Alcohols.
2010
Abstract The favourable effect of lithium bromide enhancing the facial enantioselectivity in the protonation of methyl tetralone enolate with α-sulfinyl alcohols is described. Theoretical calculations allow to propose a model to explain the stereochemical course of the protonation reaction.
Remarkable effect of lithium bromide in the enantioselective protonation with α-sulfinyl alcohols
1998
Abstract The favourable effect of lithium bromide enhancing the facial enantioselectivity in the protonation of methyl tetralone enolate with α-sulfinyl alcohols is described. Theoretical calculations allow to propose a model to explain the stereochemical course of the protonation reaction.