Über die Bestimmung von Porengrössen

Abstract

Volurnen XLII, Fasciculus VI (1959) -No. 226-227 2103 in which the structure of I1 was systematically modified, i. E. psilocin derivatives with other substitution at the w-nitrogen; derivatives of I1 substituted at the indole nitrogen; psilocin derivatives with one additional methylene group in the sidechain or with a methyl-substituted or hydroxylated side-chain ; phosphoric acid esters of some derivatives of 11; esters of I1 with organic carbonic and sulfonic acids, with methylcarbaminic and with sulfuric acid; position isomers of psilocin with the dimethylaminoethyl side-chain in position 1 or 2. Diese Beziehung gilt streng nur fur zylinderformige Poren. Bei kreisrunder Porenquerschnittsflache r % und dementsprechend einer Randlinie 2rx errechnet sich ein Formfaktor von 2/r. Vorausgesetzt, dass die Porenquerschnittsform unabhangig von

Pore-Size Distribution by a Rapid, Continous Flow Method.

“…White (16,17,18) has recently reviewed fluorometric methods. Several sensitive fluorometric methods utilize morin (3,5,7,2',4'-pentahydroxyflavone) (16), Pontachrome Blue Black R (sodium salt of 4-sulfo-2-hydroxy-l-naphthylazo-2'-naphthol) (14), 8-quinolinol (7), salicylaldehyde condensation products (9), and various hydroxyazo dyes. Colorimetric and fluorometric methods for the determination of beryllium have been reviewed by Sandell (11).…”

“…Another method, developed by Ritter and Drake (21), is based on the penetration of a nonwetting liquid, such as mercury, under pressure. An automatic mercury penetrometer was devised by Guyer (14) and commercialized. With this technique it is necessary to produce very high pressures; for pores of 150-A.…”

Adsorption and structural studies on activated carbons

“…Experiments are usually carried out with N 2 at 77 K, or with other simple gases adsorbed near their normal boiling point temperature. Since this technique covers the range of 2-50 rim, there is an interesting overlap with mercury porosimetry, providing a check for consistency [6]. In the case of carbon U, for example, it is found that there exists a significant mesoporosity in the range of 2.5 to 4.5 nm, which amounts to 0.45 cm3/g.…”

“…By using well-known experimental techniques and the equation of Kelvin [5], it is possible to characterize effectively the range of porosity (b). Macroporosity and the major part of mesoporosity can be investigated by mercury porosimetry [6], which covers approximately the range of 5-7500 nm, depending on the experimental conditions. This method is based on the relation which exists between the external pressure p and the radius rp of the smallest pores being filled by mercury, r, = (27/p) cos ~…”

Medidas de porosidad en mortero de cemento y en hormigón

“…El procedimiento del porosímetro de mercurio ha sido descrito por numerosos autores (2), ( 4), (7). El esquema del procedimiento así como el desarrollo de su utilización se halla descrito en la figura 1.…”