Paper conservation, analysis

The measurement of acidity in paper documents with cold- and hot-water extraction frequently distorts and damages the paper fibers and printing inks. Many paper conservators and museum curators have long desired a reliable and rapid method for the detection of acidity of paper documents in a nondestructive manner so that they can determine the acidity routinely to screen out valuable book documents for deacidification or other necessary preservation treatments. The objective of this chapter is to introduce two spectroscopic techniques, namely, Fourier transform IR spectroscopy (FTIR) and electron spectroscopy for chemical analysis (ESCA), for chemical analysis of paper surfaces. The effectiveness of these techniques in analyzing and determining the presence of acidic functional groups on paper documents is demonstrated. 

HPLC allows a quantitative determination with relatively simple extractions. In many cases, extraction only involves a heating of the commodity with water, followed by filtration and injection onto an HPLC column. In the determination of caffeine, theobromine, and theophylline in cocoa, coffee, or tea, as well as in other foods, there is scarcely a month that passes without a new paper on this assay. Kreiser and Martin provide typical conditions for analysis.28 In their studies, samples were extracted in boiling water and filtered prior to injection onto the HPLC column. The HPLC conditions used a Bondapak reversed phase column and a mobile phase of water methanol acetic acid (74 25 1) with detection at 280 nm. This method is accurate, precise, and conserves time. It has also been adopted by the AOAC as an official method for the determination of theobromine and caffeine in cocoa beans and chocolate products.29... 

Along with the methods of similarity theory, Ya.B. extensively used and enriched the important concept of self-similarity. Ya.B. discovered the property of self-similarity in many problems which he studied, beginning with his hydrodynamic papers in 1937 and his first papers on nitrogen oxidation (25, 26). Let us mention his joint work with A. S. Kompaneets [7] on selfsimilar solutions of nonlinear thermal conduction problems. A remarkable property of strong thermal waves before whose front the thermal conduction is zero was discovered here for the first time their finite propagation velocity. Independently, but somewhat later, similar results were obtained by G. I. Barenblatt in another physical problem, the filtration of gas and underground water. But these were classical self-similarities the exponents in the self-similar variables were obtained in these problems from dimensional analysis and the conservation laws. 

Let us also note Ya.B. s analysis of how well the conservation of electric charge has been verified (his paper together with L. B. Okun on the stability of an electron [51]), and his paper investigating the possibility of gravitational annihilation of the baryon charge [52]. 

With the busy life style and the pressure to publish papers, the problem is becoming more acute. There are deadlines to meet, technical papers need to be produced, and there is no time to explore correlation limitations. Besides, who needs to look for limitations when a computerized regression analysis (performed, of course, by one of the best regression packages in the business) shows an excellent data fit Does it really matter if a handful of points do not fit the correlation— even if this handful includes all the points for systems above atmospheric pressures In real life, no one will know, unless the designer ends up with a column that does not work. And if the error is on the conservative side, no one will ever find out, because the column will work,... 

References in general entomology usually include insects specific to fabrics and paper, although the special concerns of museum or historic conservation, older materials and natural dyestuffs, usually are not considered. A comprehensive analysis of the complete insect-related problem, including fumigation and control of textile pests, is available in Ebeling (9), or in an earlier treatise by Mallis (10). 

In this paper we have drawn on analyses carried out as part of the Maya Jade and Ceramics Project, a collaborative program of the Museum of Fine Arts, Boston and Brookhaven National Laboratory during 1977-1983. Work at Brookhaven was conducted under the auspices of the U.S. Department of Energy. Exploration into the interface between archaeological objectives, compositional variation and statistical modeling is an endeavor of the Smithsonian Archaeometric Research Collections and Records (SARCAR) facility located at the Smithsonian s Conservation Analytical Laboratory. Neffs participation in this research is made possible by a Smithsonian Institution Materials Analysis Postdoctoral Fellowship. 

In the past, although FTIR and ESCA were known to offer a great deal of information on specific chemical functional groups of surfaces, little application was made of these analytical tools in the field of conservation and restoration science and technology. A survey of instrumental analysis citations since 1953 in the conservation literature showed that only one FTIR work was published in Studies in Conservation in 1977 and two ESCA papers were published in Archaeometry in 1976. None appeared in Arts and Archaeology Technical Abstracts (AATA). 

Because both the black and the green materials contain aluminum oxide or hydroxide, a cause for the black color must be found. The amorphous copper material that shows in the EDAX results but not on the XRD pattern may be this cause. A possible source of the black color in corroded bronze is suggested by Gettens (13) in his study of the corrosion of an ancient Chinese fragment. He attributes a black color in the corrosion layers to the presence of tenorite (CuO) and states that because it is so amorphous, it gives indistinct diffraction patterns or none at all. In a later paper Gettens (14) repeats his belief that the dark product in bronze corrosion is tenorite and stresses the need for further analysis. Plenderleith (15) agrees that the dark material in bronze corrosion is tenorite, but much debate continues as evidenced by a more recently published discussion between corrosion scientists and museum conservators (16). 

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