Apparatus for the Determination of Particle Density of Porous Solids.

Abstract

unknowns are determined from the previously prepared calibration curve. RESULTS AND DISCUSSIONPrecision of the method at two carbonyl levels is shown in Table I. Data for this study, accumulated over a period of several weeks, can be compared with those of the manual method concurrently used in our laboratory. Long term precision, 2 , for the manual method, 40 analyses, is ±0.014 at a carbonyl number of 0.025. Samples A and B which were used in establishing the precision of the automated procedure were prepared from crude oxo alcohols which had been dissolved in pure decvl alcohol.Table II shows the results of a crosscheck program using the extractive method of Lohman (£) as referee. The samples used in the study were actual plant samples of oxo alcohols. Agreement between the two methods is excellent.Because the samples used in these studies all had specific gravities which varied within a few per cent of one another, no correction for changes in specific gravity was made in the analytical calculations. Where large changes in specific gravity of the samples are encountered, corrective measures should be taken.The automated procedure is being used in our analytical laboratories for routine analyses. On a single sample, elapsed time per analysis is less than 1 hour. For samples in groups of 10 or more, time per sample is about 0.1 hour. The system can handle as many as 70 to 80 samples per 8-hour day with a minimum of operator attention.

Solid Support Characteristics and Plate Height in Gas Chromatography.

“…Boyack and Giddings (6) and Knox and McLaren (27) were able to estimate C and T for packings with regular geometrical shapes in terms of the void fraction, so the contribution to 7 from the interand intraparticle paths should be a function, , of and e" respectively. Thus 7 = 7z> + 7» = <t>A*v) + 0v(e«) (7) where yp and 7,. are the interand intraparticle contributions to 7, respectively.…”

“…Packing Characteristics. The particle density (pv) was measured by using the method of Cartan and Curtis (7). One-atmosphere pressure was sufficient to outline the particles with negligible penetration of the mercury into the particle interior.…”

“…The interparticle void fraction, e", was measured by the equation = 1 -m/ppVc (4) where m is the mass of the packing, pp is the individual particle density measured by outlining the particle under mercury (7), and Vc is the total volume of the column. The intraparticle void fraction, e", was measured by using the equation…”

“…A brief communication (7) reported the use of packed capillary columns in gas chromatography. The columns should have an inner diameter of less than 1 mm.…”

Απομάκρυνση Βαρέων Μέταλλων Από Υδατικά Διαλύματα Με Χρήση Φυσικών Ορυκτών

“…Χζηφζν, είλαη δχζθνιν πεηξακαηηθά λα κεηξεζεί άκεζα ν φγθνο ησλ ζσκαηηδίσλ. πσο ζα αλαθεξζεί παξαθάησ έλαο απιφο ηξφπνο είλαη ν ππνινγηζκφο ηνπ φγθνπ ηνπ ζσκαηηδίνπ, απφ ηνλ φγθν ηνπ πγξνχ πνπ απμάλεηαη κε ηελ πξνζζήθε ηνπ ζσκαηηδίνπ εληφο ηνπ ξεπζηνχ (Gotoh et al, 1997;Rouquerol, 1994;Cartan and Curtis, 1963).…”