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Emil Ghiocel Ioanid Aurelia Ioanid Dorina Emilia Rusu Carmen-Mihaela Popescu Iuliana Stoica 《Journal of Cultural Heritage》2011,12(4):399
Recent research, concerning the application of high-frequency cold plasma in restoration and preservation of the cultural heritage, has included the objects derived from organic materials, which are highly sensitive to microclimate factors. Historical photographs made on paper base and covered with various emulsions belong to this category of heritage objects, and make the purpose of the present study. Plasma treatment was used to enhance the aesthetic aspect of the photographs by a cleaning treatment involving either physical and/or chemical etching, which did not cause major physicochemical changes on the plasma-treated surface. The photographs before and after plasma treatments were analysed by optical and atomic force microscopy, scanning electron microscopy with energy-dispersive X-ray microanalysis, Fourier transform infrared spectroscopy, colour, gloss and contact angle measurements. 相似文献
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Tomasz Sawoszczuk Andrzej Baraski Janusz Marek agan Tomasz ojewski Katarzyna Ziba 《Journal of Cultural Heritage》2008,9(4):401-411
The ASTM D6819-02e3 standard for testing the accelerated ageing of paper, published in 2002, recommends using closed glass vials in order to keep the degradation products in contact with the paper and thus permitting a better simulation of the natural ageing conditions inside closed books. In the present study, the actual conditions and their stability inside closed vessels have been evaluated. The necessity of assuring a very high sealing performance (tightness) of the systems in order to avoid leakage of water vapour is the main drawback of this ageing method. Systematic studies presented in this publication tried to monitor this tightness and have provided data that helped to answer the question of what circumstances could lead to achieving its improvement. Both gravimetric monitoring of water content in vials and “in situ” IR measurements of the aged paper humidity have been applied for this purpose. As a result, better sealing materials (gaskets and caps) than those recommended by the ASTM standard, have been found. Additionally, application of a dynamometric spanner for closing the vials is recommended, as this is a guarantee of reasonably high and recurring tightness of the systems used in tests. Nevertheless, the systematic, linear with time, loss of moisture for all used vials was observed. A 9% loss of the initial moisture content in samples of the aged paper was observed for the tested conditions (14 days at 90 °C). Therefore, it seems that including some kind of gravimetric control for ageing tests performed in closed vessels is of essential importance.Kinetic studies of accelerated ageing in both closed and open systems, as monitored by DP and breaking length measurements, unexpectedly show that no statistically meaningful difference of degradation rates can be observed. On the other hand, the pH and whiteness index values reveal a meaningful difference between the rates of ageing in these systems, thus confirming the basic assumption of the ASTM test concerning the interaction of paper degradation products with the paper itself. 相似文献
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Katarzyna Polak Jerzy Stanisław Gielecki Anna Żurada 《Anatomical sciences education》2022,15(6):1060-1073
The affordances of technology-based assessments, like the objectively structured practical examination, have become an integral part of gross anatomy courses. The Department of Anatomy Faculty of Medicine at the University of Warmia and Mazury developed and introduced an application for tablet devices which has been implemented in student examinations and assessments, called the tablet-assisted objective structured spotter practical examination. It was created to simplify the educational process and to build a rich learning environment, facilitating deep learning for students through examination and feedback data. The method consists of cadaver stations with traditional corresponding pin spotters in an expanded tablet application. It not only provides instant feedback on various observations of teaching–learning skills but has also positively affected the entire process of education. The method provides an unbiased evaluation of knowledge and understanding of the anatomy course, ensuring objectivity and standardization. The current study was performed on a total of 608 first-year medical students in Polish and English divisions and focused on the observed advantages since the new method was introduced. Outcomes indicate that after the implementation of the method for both the Polish and English divisions' first-year medical students, the mean score of examinations significantly increased compared to other teaching–learning methods. The study highlights that students were excited about the implementation of the new method and identified its many benefits. It is recognized that technological development and the digital environment offer a range of opportunities and added value versus traditional assessment activities, methods, and processes. 相似文献