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log 10 of Acetonitrile vapor pressure. ... UV-Vis; λ max? nm: Extinction coefficient, ε ? IR; Major absorption bands [5] (liquid film) Wave number
Acetonitrile is used mainly as a solvent in the purification of butadiene in refineries. Specifically, acetonitrile is fed into the top of a distillation column filled with hydrocarbons including butadiene, and as the acetonitrile falls down through the column, it absorbs the butadiene which is then sent from the bottom of the tower to a second separating tower.
This is a crucial property for common reversed phase chromatography since sample components are typically detected by UV detectors. Acetonitrile is more transparent than the others in low UV wavelengths range, therefore it is used almost exclusively when separating molecules with weak or no chromophores (UV-VIS absorbing groups), such as ...
In physics and physical chemistry, time-resolved spectroscopy is the study of dynamic processes in materials or chemical compounds by means of spectroscopic techniques.Most often, processes are studied after the illumination of a material occurs, but in principle, the technique can be applied to any process that leads to a change in properties of a material.
Add the amine to di-tert-butyl dicarbonate, 4-dimethylaminopyridine (DMAP), and acetonitrile (MeCN) at ambient temperature [15] BOC-protected amines are prepared using the reagent di-tert-butyl-iminodicarboxylate. Upon deprotonation, this reagent affords a doubly BOC-protected source of NH − 2, which can be N-alkylated.
Phase behavior Triple point: 178.5 K (−94.3 °C), ? Pa Critical point: 508 K (235 °C), 48 bar Std enthalpy change of fusion, Δ fus H o +5.7 kJ/mol Std entropy change
In solution, the intensity of charge-transfer bands in the UV-Vis absorbance spectrum is strongly dependent upon the degree (equilibrium constant) of this association reaction. Methods have been developed to determine the equilibrium constant for these complexes in solution by measuring the intensity of absorption bands as a function of the ...
In biochemistry, the molar absorption coefficient of a protein at 280 nm depends almost exclusively on the number of aromatic residues, particularly tryptophan, and can be predicted from the sequence of amino acids. [6] Similarly, the molar absorption coefficient of nucleic acids at 260 nm can be predicted given the nucleotide sequence.