Chemical reaction, absorption

Chemical reaction, absorption. Here the much higher liquid holdup on trays provides greater residence time for absorption or chemical reaction than does packing. 

Stage 8 Knowing the number of moles of acid formed by chemical reaction/absorption, the moles of acid and water required from the... 

Dyes n. Substances that add color to textiles. They are incorporated into the fiber by chemical reaction, absorption, or dispersion. Dyes differ in their resistance to sunlight, perspiration, washing, gas, alkalies, and other agents their affinity for different fibers their reaction to cleaning agents and methods and their solubility and method of application. Various classes and types are listed below. 

Kohl, A. L., 1956, Plate Efficiency with Chemical Reaction— Absorption of Carbon Dioxide in Mononethanolamine Solutions, , 4/CA 7., Vol. 2, June, p. 264. 

Gases which are high in FIjS are subject to a de-sulphurisation process in which H2S is converted into elemental sulphur or a metal sulphide. There are a number of processes based on absorption in contactors, adsorption (to a surface) in molecular sieves or chemical reaction (e.g. with zinc oxide). 

So far we have exclusively discussed time-resolved absorption spectroscopy with visible femtosecond pulses. It has become recently feasible to perfomi time-resolved spectroscopy with femtosecond IR pulses. Flochstrasser and co-workers [M, 150. 151. 152. 153. 154. 155. 156 and 157] have worked out methods to employ IR pulses to monitor chemical reactions following electronic excitation by visible pump pulses these methods were applied in work on the light-initiated charge-transfer reactions that occur in the photosynthetic reaction centre [156. 157] and on the excited-state isomerization of tlie retinal pigment in bacteriorhodopsin [155]. Walker and co-workers [158] have recently used femtosecond IR spectroscopy to study vibrational dynamics associated with intramolecular charge transfer these studies are complementary to those perfomied by Barbara and co-workers [159. 160], in which ground-state RISRS wavepackets were monitored using a dynamic-absorption technique with visible pulses. 

Raksi F, Wilson K R, Jiang Z, Iklef A, Cote C Y and Kieffer J-C 1996 Ultrafast x-ray absorption probing of a chemical reaction J. Chem. Phys. 104 6066-99... 

Wynne K and Hochstrasser R M 1995 Anisotropy as an ultrafast probe of electronic coherence in degenerate systems exhibiting Raman scattering, fluorescence, transient absorption and chemical reactions J. Raman Spectrosc. 26 561-9... 

Selectivity Selectivity is rarely a problem in molecular absorption spectrophotometry. In many cases it is possible to find a wavelength at which only the analyte absorbs or to use chemical reactions in a manner such that the analyte is the only species that absorbs at the chosen wavelength. When two or more species contribute to the measured absorbance, a multicomponent analysis is still possible, as shown in Example 10.6. 

Discussion of the concepts and procedures involved in designing packed gas absorption systems shall first be confined to simple gas absorption processes without compHcations isothermal absorption of a solute from a mixture containing an inert gas into a nonvolatile solvent without chemical reaction. Gas and Hquid are assumed to move through the packing in a plug-flow fashion. Deviations such as nonisotherma1 operation, multicomponent mass transfer effects, and departure from plug flow are treated in later sections. 

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