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The identification of the constituents of inks can play an important part in the conservation and restoration of manuscripts. Capillary vapour phase chromatography was used to analyze old inks, following methanolysis and silylation. The technique was applied to two reference samples of old ink which weighed less than 100µg and several inks from various kinds of document were also analyzed. When the support of the documents was parchment, the nature of the ink was always identified: a more or less degraded gum was present in all the binding media, sometimes associated with other products. However, it was not possible to interpret the analysis of documents on paper. It is difficult to take samples of ink and they always contain a fragment of the support. The peaks from the paper overlap those of the ink, as can be seen by comparing the chromatograms of the support alone and the sample supposed to be only ink. [ABSTRACT FROM AUTHOR]

Abstract: We study in this paper the transport and deposition of suspended particles in saturated porous media. Some chromatographic short-pulse tests were performed in a laboratory column with a tracer and two types of suspended particles. A mathematical model was used to determine the hydrodispersive parameters and deposition rates from the breakthrough curves. The results show that the fitted parameters obtained vary with the flow rate and the characteristics of the suspended particles. We also observe, at high flow rates, that particles have a migration velocity higher than that of the conservative tracer. To cite this article: A. Benamar et al., C. R. Geoscience 337 (2005). [Copyright &y& Elsevier]

A spectrophotometric technique after paper chromatography was found adequate for quantitatively determining chlorogenic and caffeic acids in the vegetative apical buds of Pyrus communis L., variety ‘Passe‐Crassane’, de ľOrléanais. Using this method, significant changes in these polyphenols were shown to occur both in tissue concentration and total amount per bud, in samples collected during winter 1973–1974. A close relationship between chlorogenic acid concentration and state of dormancy of excised twigs was found. [ABSTRACT FROM AUTHOR]

Various methods of bleaching in common use have been studied. Three types of aged paper (rag, chemical and mechanical woodpulp) were washed, deacidified, bleached, deacidified again and artificially aged. The physico-chemical effects of bleaching were measured by the degree of overbleaching, yellowing and loss of mechanical resistance as well as by analysis by electron microprobe and gel permeation chromatography. Seven methods were finally retained and their application is described in detail. [ABSTRACT FROM AUTHOR]

Presents an investigation of the sequencing of 65 amino acid residues at the carboxyl-terminus. Use of methods such as enzymic or chemical cleavages of the peptide chain; Fractionation of peptides by Sephadex or Dowex column chromatography, paper elctrophoresis or chromatography.