7 results match your criteria: "National and University Library[Affiliation]"

Non-destructive, fast, and accurate methods of dating are highly desirable for many heritage objects. Here, we present and critically evaluate the use of near-infrared (NIR) spectroscopic data combined with three supervised machine learning methods to predict the publication year of paper books dated between 1851 and 2000. These methods provide different accuracies; however, we demonstrate that the underlying processes refer to common spectral features.

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Determination of Cellulose Degree of Polymerization in Historical Papers with High Lignin Content.

Polymers (Basel)

June 2021

Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna Pot 113, 1001 Ljubljana, Slovenia.

Determination of cellulose degree of polymerization (DP) is one of the most commonly used methods in paper degradation studies, performed either by a standardized method using viscometry (as average degree of polymerization (DP)) or size-exclusion chromatography (SEC) (as weight average molecular mass (M)). Due to the insolubility of papers with high lignin content in cupriethylenediamine (CED), such as groundwood papers, viscometric determination is not possible; therefore, pretreatment is required to allow subsequent dissolution of the papers. In this study, the pretreatment of historical papers containing groundwood with sodium chlorite in acetic acid was investigated, which enables dissolution of the paper samples in CED and determination of the cellulose average degree of polymerization by viscometry (DP).

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Herein, colloidal dispersions of alkaline nanoparticles (NPs: CaCO and Mg(OH)) are stabilized by trimethylsilyl cellulose (TMSC) in hexamethyldisiloxane and employed to treat historical wood pulp paper by an effortless dip-coating technique. Both alkaline NPs exhibit high stability and no size and shape changes upon stabilization with the polymer, as shown by UV-vis spectroscopy and transmission electron microscopy. The long-term effect of NP/TMSC coatings is investigated in detail using accelerated aging.

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Volatile organic compounds (VOCs) emitted from materials during degradationcan be a valuable source of information. In this work, the emissions of furfural and aceticacid from cellulose were studied using solid-phase micro-extraction (SPME) incombination with gas chromatography-mass spectrometry. Two sampling techniques wereemployed: static headspace sampling using SPME for 1 h at 40 C after 18-h samplepreparation at 80 C in a closed glass vial, and contact SPME in a stack of paper (or abook).

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Two myo-inositol phosphates, myo-inositol 1,2,3-tris(dihydrogen phosphate) and myo-inositol 1,2,3,5-tetrakis(dihydrogen phosphate), have been synthesised in several steps from myo-inositol (in Chem. Abstr.: d-myo-inositol) in the form of their sodium salts.

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Some new medical manuscripts from Moscow.

Korot

June 1995

Institute of Microfilmed Hebrew Manuscripts, Jewish National and University Library, Jerusalem.

Among the approximately two thousand manuscripts of the Guenzburg collection at Moscow which have recently been filmed on behalf of the Institute of Microfilmed Hebrew Manuscripts, about three dozen contain medical treatises. Of these, six display works of singular importance whose existence and contents have not yet been brought to the attention of scholars. The purpose of this article is to describe these new materials in some detail.

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