Gas chromatographic analysis of aliphatic and aromatic hydrocarbons with 2,4,5,7-tetranitrofluorenone-modified graphitized carbon black

Aqueous Suspensions of Poly(ethylene Glycol)/Pyrocarbon/Fumed Silica

“…The FG equation was used as a local isotherm l in the overall adsorption isotherm in the form of a Fredholm integral equation of the first kind [9] where f (y) is the unknown distribution function of a given parameter y over the y min − y max range, to calculate the adsorption energy distribution f (E). For this purpose, a regularization method can be used (22, 26), as solution of Eq.…”

“…For this purpose, a regularization method can be used (22, 26), as solution of Eq. [9] (which has no general solution) is a well known ill-posed problem due to a strong influence of noise components in the experimental data (a small variation in the experimental data can cause a large variation in f(y)), which do not allow us to utilize exact inversion formulas or iterative algorithms. The CONTIN program package (22) was modified to utilize different adsorption isotherm equations (27).…”

“…Changes in the surface properties of carbon-mineral adsorbents can occur due to immobilization of polar polymers (e.g., poly(ethylene glycol), PEG). Colloidal dispersions with solid adsorbents, polymers, and low-molecular compounds are applied, e.g., in high-selective chromatographic columns (9,10). The characteristics of such dispersions depend on the state of the solvate shells (electrical double layer, EDL) of solid particles 1 To whom correspondence should be addressed.…”

The Column in Gas Chromatography

“…Polar adsorption sites are few in number but they can establish specific, strong interactions with polar solutes. At high liquid phase loadings the adsorbent behaves as a support for the bulk liquid [463,464]. For example, heating to 1000°C in a stream of hydrogen has been used to minimize those active sites associated with the presence of surface oxygen complexes [435,436,459] while washing with perchloric or phosphoric acid eliminates basic carbonium-oxygen complexes and sulfur present as sulfide [460].…”

A bonded polyoxyethylene phase for gas and liquid chromatography

“…In a-wider context, layers oriented within the range of surface forces are fascinating though complex objects of study. The interests involved range from basic investigations in physical chemistry (55,56) and chromatography (57)(58)(59)(60)(61)(62)(63)(64)(65), over biological interfaces, adhesive joints, and the oceans' top layer, to dishwashing (66,67). Some physicochemical aspects of thin layers, as seen by gas chromatography, have been reviewed (68).…”