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Several kinds of paper (Bond, Amate, Rice, Press, and Whatman#1) were studied in their original condition and were then exposed to gamma radiation between 3 and 15 kGy (0.9 kGy/h) with intervals of 3 kGy. The length and width of fibers (SEM) as well as pH were measured, and the chemical composition was determined by EDS. Pyrolysis characteristics (TGA and DTC), transmittance spectra by IR and X-ray diffraction patterns were studied as well. Whatman#1 contains only cellulose; whereas Bond, Press and Rice papers also contain calcite and Amate whewellite. All X-ray diffraction patterns showed Type I semicrystalline cellulose, but a slight presence of Type II was noted in the artisan papers (Amate and Rice). These results were confirmed by IR spectra and thermogravimetric analyses. Due to gamma irradiation no acidification nor change of fiber sizes or alteration of other studied parameters were observed. Therefore, these conditions may be recommended for the treatment of some deteriorated documents. [ABSTRACT FROM AUTHOR]

The Ottoman Archives have one of the richest archive collections in the world. However, not all the archived documents are well preserved and some undergo biodeterioration. Therefore, a rapid and promising treatment method is necessary to preserve the collection for following generations as heritage. Radiation presents as an alternative for the treatment of archival materials for this purpose. In this study, we conducted a survey to determine the contamination species and the D 10 values of the samples obtained from the shelves of the Ottoman Archives. The samples also included several insect pests collected at using a pheromone trap placed in the archive storage room. With the exception of few localized problems, no active pest presence was observed. The D 10 values of mold contamination and reference mold ( A. niger ) were found to be 1.0 and 0.68 kGy, respectively. Based on these results, it can be concluded that an absorbed dose of 6 kGy is required to remove the contamination from the materials stored in the Ottoman Archives. [ABSTRACT FROM AUTHOR]

The effectiveness of ionizing radiations for the preservation of cultural heritage (CH) has been recently demonstrated. Although these processes present many advantages with respect to the traditional methods, physico-chemical modifications induced by radiation (namely side effects) represent a concern for CH restorers, archivists and librarians. The present work is focused on the study of the effect of gamma irradiation parameters on the main features of paper. In particular, total absorbed doses up to 10 kGy (commonly suggested for preservation treatments) have been applied, with dose rates ranging from 3 to 10 kGy/h. Different experimental techniques (FTIR, EPR, viscosity and colorimetric analysis) have been used to study the side effects occurrence. The results indicate that the fine-tuning of irradiation condition allow to minimize the unwanted changes, induced by radiation in the treated paper samples. • Gamma radiation at absorbed doses common for preservation of cultural heritage (up to 10 kGy). • Side effects evaluation with several experimental techniques (FTIR, EPR, DP, colorimetric analysis). • Studies were performed at different dose rate values. • Irradiation parameters optimization to minimize the side effects. • Gamma rays represent a suitable and reliable tool for bio-deteriogens elimination purpose. [ABSTRACT FROM AUTHOR]

The identification of forged and genuine historical banknotes is an important problem for private collectors and researchers responsible for the care of numismatic collections. This paper presents a research approach for detecting material differences in historical banknotes through the use of microfading spectrometry along with other techniques such as hyperspectral image analysis, Fourier-transform infrared spectroscopy, and X-ray fluorescence spectrometry. Microfading spectrometry results showed higher sensitivity to light irradiation for an overprint ink used on a suspicious banknote relative to its counterparts. In addition, the spectrocolorimetric changes experienced by the paper substrates during microfade testing also provided a way for discriminating between two groups of banknotes. These variations have been confirmed after analyzing the spectral and physico-chemical data obtained using the abovementioned complementary techniques. [ABSTRACT FROM AUTHOR]

AbstractSamples of two historical papers from the late 17th and early 18th centuries were irradiated with a 350-nm ?maxlight source. Atomic force microscopy examination of untreated samples of these laid paper sheets revealed notable surface inhomogeneity. Diffuse brightness values show that irradiation resulted in an initial decrease followed by a rapid increase in brightness with increasing irradiation time from 0.5 to 28 h. The bleaching effect then slowed, following a logarithmic path that did not plateau within 197 h of irradiation time. Irradiated sheets stored for 3 months exhibited brightness reversion of 7%. Fluorescence also decreased with irradiation time if excitation wavelengths of 320, 350, and 400 nm were applied for samples exposed to narrow-band irradiation at 350 nm. The fold endurance decreased by 34–72% after 197 h of irradiation. Changes in tear and tensile values were less dramatic. The Z-direction ultrasonic velocity decreased after 197 h of irradiation; however, the ultrasonic conductivity partially recovered during 9 months of storage. [ABSTRACT FROM AUTHOR]

Fabriano paper was aged by irradiation with ultraviolet light (λ=310) in a veterometer for 300 hours. At fixed time intervals, samples of the paper under test were analysed by titanium dioxide photosensor to determine electrochemically the ‘environmental persistence’ index, by a suitable conductimeter method, to determine the specific conductivity variation and by thermogravimetry to determine the moisture content, the onset temperature of the cellulose degradation process and the value of the activation energy of the same process. The behaviour of these different types of indicators displayed approximately monotonous trends as a function of time. [ABSTRACT FROM AUTHOR]

The article focuses on a research conducted in order to examine the effects of post-radiation on various kinds of paper. This effect was examined on the basis of changes in relative humidity, the type of the light source and the change on secondary irradiation. The research revealed that post-radiation effect (PRE) is more intense for materials irradiated by a source of daylight as compared to a high ultraviolet source. Following irradiation by daylight, there is a rapid increase on the dependence of PRE on the relative humidity between values of 53 percent and 62 percent.

Features a study that examined the susceptibility of printed paper to attack of chewing insects after gamma irradiation and ageing. Effects of irradiation on the mechanical and chemical characteristics of paper; Types of paper used in the experiment; Relationship between the gamma dose absorbed by the paper and the erosion caused on it by the chewing insect.

The long-term effect of gamma irradiation on paper was studied. Three types of paper (pure rag, mixed rag and mechanically prepared woodpulp) were subjected to three treatments: gamma irradiation, accelerated dry aging, and radiation followed by aging. The effects of these treatments on the physical properties of the paper samples were assessed by measuring alterations in mechanical strength as determined by changes in folding endurance and tear resistance when compared to the untreated control samples. It was found that gamma irradiation caused a decrease in the mechanical strength of the papers similar to that resulting from accelerated dry aging. A synergistic effect was found when both irradiation and accelerated aging were performed on the paper samples, demonstrated by an even greater decrease in both fold endurance and tear resistance than that resulting from either gamma irradiation or accelerated dry aging alone. [ABSTRACT FROM AUTHOR]