Nanotechnologies and Nanomaterials for Diagnostic, Conservation and Restoration of Cultural Heritage

Giuseppe Lazzara,Rawil F. Fakhrullin

• Éditeur: Elsevier
• Année: 2018
• ISBN:
  9780128139110
• Sujet: Scienze fisiche
• Sous-sujet: Nanoscienze

Nanotechnologies and Nanomaterials for Diagnostic, Conservation and Restoration of Cultural Heritage explores how advanced nanoscale techniques can help preserve artworks. The book covers lab-scale available techniques as well as advanced methods from neutron sources and X-ray spectroscopy. Other sections highlight a variety of nanomaterials with potential uses in treatments for restoration and conservation, with conservation, consolidation and long-term protection protocols analyzed in each case. The final chapter presents case studies, demonstrates how nanoscale techniques are used to conserve art, and shows what happens when misinterpretation of data sources leads to misdiagnosis.

The book is intended for scientists from academic and professional conservators, restorers who are involved in the conservation of artistic and historical artifacts, and those who want to learn how nanotechnology can increase the efficiency of conservation and protection techniques.

• Cogently explains how nanotechnology is used in the preservation, protection and restoration of artworks
• Explores the best nanomaterials for a variety of situations
• Shows how nanomaterials can be used in restoration, for cleaning and in conservation treatments
• Includes guidelines to prevent the misinterpretation of diagnostic data to help avoid misdiagnosis

Chapter 1

Advanced Microscopy Techniques for Nanoscale Diagnostic of Cultural Heritage

Scanning Electron Microscopy for Investigation of Medieval Coins and Frescos From the Republic of Tatarstan

Rezida Khramchenkova^1,2, Ilvina Safina³, Sergey Drobyshev³, Svetlana Batasheva⁴, Evgeny Nuzhdin³, and Rawil Fakhrullin^{4 1}Analytical and Restoration Department, Institute of Archaeology, Academy of Sciences of the Republic of Tatarstan, Kazan, Republic of Tatarstan, Russian Federation ²Archeotechnologies and Archeological Material Sciences Laboratory, Institute of International Relations, History and Oriental Studies, Kazan Federal University, Kazan, Republic of Tatarstan, Russian Federation ³Centre for collective use “Applied nanotechnologies”, Kazan National Research Technical University named after A.N. Tupolev, Kazan, Republic of Tatarstan, Russian Federation ⁴Bionanotechnology Lab, Institute of fundamental medicine and biology, Kazan Federal University, Kazan, Republic of Tatarstan, Russian Federation

Abstract

Microscopic methods make it possible to investigate the surface structure of objects in varying detail, but being integrated with other physical methods of analysis, they also allow study of the chemical composition of the object, eventually drawing conclusions about the origin of the object or its initial components, method or time of its creation, author(s), purpose, authenticity, mechanisms of degradation, and ways of further conservation. At present, different kinds of microscopy can be applied to such a wide range of cultural heritage objects as paintings, murals and frescoes, manuscripts and books, statues, precious stone products as well as various objects made of leather, fabric, stone, ceramics, glass, wood, or metal. One of the tendencies for future development in the area is associated with the desire for greater portability of research microscopic equipment, since many subjects of research cannot be moved to the laboratory, either because of their size, inseparability (for example, cave and mural paintings), or the threat to their preservation. In this chapter we will try to briefly overview the main microscopic methods used for the study of cultural heritage objects, indicating the scope of their application as well as the degree of portability, and to demonstrate the application of microscopic methods for investigation of a series of artifacts from the Volga region. The first are medieval silver coins once passed on the territory of the Middle Volga Region. The second is the fresco base (levcas in Russian) and the paint layer of a unique mural dating from the 16th century, miraculously preserved in the Assumption Cathedral of the town of Sviyazhsk in the Republic of Tatarstan.

Keywords

Correlative microscopy; Cultural heritage; Optical microscopy; Scanning electron microscopy, Chemical composition, Nanoscale characterization

Chapter Outline

1. 1.1 Introduction
2. 1.2 Optical Microscopy and Confocal Optical Microscopy
3. 1.3 Raman Microscopy
4. 1.4 Fourier Transform Infrared Microscopy
5. 1.5 Electron Microscopy
   1. 1.5.1 Transmission Electron Microscopy
   2. 1.5.2 Scanning Electron Microscopy
6. 1.6 Atomic Force Microscopy
7. 1.7 Correlative Optical and Scanning Electron Microscopy: A Case Study
   1. 1.7.1 SEM\EDS Characterization of Islamic Coins Found in Excavation Sites of Volga Bulgary (Republic of Tatarstan)
   2. 1.7.2 SEM\EDS Characterization of Fresco Base From the Assumption Cathedral of Sviyazhsk (Republic of Tatarstan)
8. 1.8 Conclusions
9. Acknowledgments
10. References

1.1. Introduction

The study of objects of cultural heritage as particularly valuable products of human civilization development has been regarded as a matter of great importance. Once a prehistoric human discovered the first unusual artifact, a collecting phenomenon arose and the process of accumulating values created by skilled craftsmen of different eras began. Initially, scientific research in the area was stimulated by the need for restoration and understanding the degradation processes occurring in the objects of cultural heritage. As any human creation, whether ancient ceramics, jewelry, artwork, or architectural masterpiece, tends to deteriorate in course of time, the issue of scientific restoration becomes increasingly important. For successful restoration it is necessary to characterize the quantitative and qualitative changes that occurred in the material structure of the artifact under the influence of physical, chemical, biological, and other factors that determine the degree of its preservation or destruction. The researcher also needs to answer the questions related to the processes of the object creation and describe the substance from which the monument was made, determining its composition and mechanical properties, as well as the technical and technological methods used to create the artifact. The urgency of these tasks determines the growing need for analytical studies of cultural heritage objects.

Most of the objects of cultural heritage are unique and invaluable; therefore one of the main requirements for the study of such artifacts is the minimal destruction during sample preparation; ideally the sample preparation should be nondestructive. It is not surprising then, that sooner or later a microscope becomes one of the necessary elements of almost any system of research of cultural artifacts. It is not an absolutely nondestructive technique because usually it also requires sampling, but the sample in many cases is not completely destroyed during microscopic investigation and can be thoroughly studied by sequential application of different methods (Trentelman, 2017).

Basically, any optical microscope contains a source of illumination, a condenser system, an objective lens, an eyepiece, and an image recording system. The main characteristic of the microscope is its resolving power—the ability to give a separate image of two closely located points. The theoretical resolution of the light microscope is 0.2–0.3 μm when using the visible spectral region, and 0.13–0.14 μm when using light in the UV range (the resolution of the human eye is only 0.1 mm). The development of an electron microscope increased the possible resolving power to fractions of a nanometer. Another high-resolution microscopy system with a completely different principle of operation is atomic force microscopy; there the sample surface is scanned by a thin-tip probe, providing topographical information reaching incredible, up-to-atomic resolution. In addition, atomic force microscopy, as a sample-touching technique, provides nanomechanical data from the samples. There are other types of microscopy systems, but not all of them are currently used to study cultural artifacts.

In general, microscopic methods enable investigation of the structure of objects at various magnifications, but being integrated with other physical methods of analysis, they also allow study of the chemical composition of the objects, eventually drawing conclusions about the origin of the object or its initial components, method or time of its creation, author(s), purpose, authenticity, mechanisms of degradation, and ways of further conservation. At present, different kinds of microscopy can be applied to investigate a wide range of cultural heritage objects such as paintings, murals and frescoes, manuscripts and books, statues, precious stone products as well as various objects made of leather, fabric, stone, ceramics, glass, wood, or metal. One of the tendencies for future development in this area is associated with the desire for greater portability of research microscopic equipment, since many subjects of research cannot be moved to the laboratory, either because of their size or inseparability (for example, cave and mural paintings), or threat to their preservation. In this chapter we briefly overview the main microscopic methods used to study cultural heritage objects, indicating the scope of their application as well as the degree of portability. Here we omit detailed technical information on the functioning and manipulation with microscopes, which can be found elsewhere in numerous publications devoted to each particular microscopy technique. Instead, we try to introduce the reader to the application in cultural heritage nanoscale studies based on the use of various microscopic techniques, including the combinations of several techniques. Also, here we demonstrate several case studies for the application of microscopic methods for investigation of a series of cultural heritage objects found in the Republic of Tatarstan. We have successfully utilized correlated optical and scanning electron microscopies to investigate and characterize the following artifacts: the first case is Islamic medieval silver coins circulating in Volga Bulgary and Golden Horde during the 9th to 15th centuries AD. The second case is the fresco base (plaster substrate) and paint layer of a mural dating from the 16th century, preserved in the Orthodox ...