scholarly journals Microscopical Methods for the In Situ Investigation of Biodegradation on Cultural Heritage

Author(s):  
Verginica Schröder ◽  
Daniela Turcanu Carutiu ◽  
Adina Honcea ◽  
Rodica-Mariana Ion
2010 ◽  
Vol 133-134 ◽  
pp. 1165-1169
Author(s):  
Amina Abdessemed-Foufa ◽  
Abdelwahab Zekagh ◽  
Houria Merouani

In Algeria, several old urban nuclei are decayed or severely damaged. Numerous are the factors related to these damages: the age of constructions (many centuries), the bad or absence of maintenance, the natural disaster (earthquake, landslide, and floods) and sometimes the abandonment. Since 2003, the law 98-03 related to the preservation of cultural heritage and its application decree was implemented. In fact the first safeguard sector plan in Algeria was applied to the Casbah of Algiers which is classified as a World Heritage. This old urban nucleus presents an important decay. The different problems related to its aspect are principally the age of constructions; some of them date from the 10th century and the majority of the 16th; the absence of maintenance and recently in 2003 the impact of the earthquake. The project is still under investigation and is established by the CNERU Group (National Center in Urban Research and Studies). Furthermore the work on these areas was done under constraints. The Casbah of Algiers is a World Cultural Heritage, what induced us the installation of emergency measures (propping up), then in parallel an in situ investigation in order to determine the vulnerability of constructions was done (minor and major inheritance, houses and buildings) in order to elaborate the manual of rehabilitation and the safeguard plan and its regulation. This paper presents the adopted methodologies in this area and the different actions as the emergency measures, the constructions propping up and the manual of rehabilitation.


Author(s):  
Bernd Jürgen Fitzner

Abstract: Stone monuments represent an important part of our world´s cultural heritage. The awareness of increasing stone damage on monuments and the danger of irretrievable loss of cultural heritage have resulted in great efforts worldwide for sustainable monument preservation. A precise damage diagnosis with the comprehensive characterization, interpretation and rating of stone damage represents the basis for effective and economic monument preservation measures. The experienced methodological approach to the assessment of stone damage combines in situ investigation and laboratory studies. The monument mapping method is presented as an established non-destructive procedure for in situ studies on stone damage. It can be applied to all stone types and to all kinds of stone monuments. The use of weathering forms, damage categories and damage indices for the registration, documentation, quantitative evaluation and rating of stone damage is explained. Furthermore, complementary in situ measurements are discussed. A wide range of analytical procedures and weathering simulation tests contribute to modern damage diagnosis on stone monuments.Keywords: damage, stone, monumentsResumo: INVESTIGAÇÃO SOBRE DANOS DO INTEMPERISMO PARA MONUMENTOS EM PEDRA. Os monumentos em pedra representam uma parte importante do patrimônio cultural do mundo. A consciência do aumento dos danos causados ao material pétreo nesses monumentos e o perigo de perda irrecuperável desse património resultaram em grandes esforços a nível mundial para a preservação sustentável desses monumentos. Um diagnóstico preciso de danos com a caracterização, interpretação e avaliação abrangentes desses danos causados às pedras representa a base para a adoção de medidas de conservação eficazes e econômicas. A abordagem metodológica a ser adotada para a avaliação desses danos deve combinar a investigação in situ e estudos laboratoriais. Nessa abordagem o mapeamento de monumentos é apresentado como um procedimento não destrutivo estabelecido para os estudos in situ sobre danos causados às pedras, podendo ser aplicado a todos os tipos de pedra e a todos os tipos de monumentos construídos com a pedra. Nesse trabalho, o uso de formas de intemperismo, categorias de danos e índices de danos para o registro, documentação, avaliação quantitativa e classificação de danos para a pedra é explicado. Além disso, discutem-se medidas complementares a serem adotadas in situ. Uma ampla gama de procedimentos analíticos e testes de simulação de meteorização contribuem para o diagnóstico de danos modernos em monumentos construídos em pedra.Palavras Chave: dano, pedra, monumentos


2021 ◽  
pp. 000370282199877
Author(s):  
Eva Mariasole Angelin ◽  
Susana França de Sá ◽  
Inês Soares ◽  
Maria Elvira Callapez ◽  
Joana Lia Ferreira ◽  
...  

Plastics have been increasingly used to create modern and contemporary art and design, and nowadays, museum collections hold numerous objects completely or partially made of plastics. However, the preservation of these materials is still a challenging task in heritage conservation, especially because some plastics show signs of degradation shortly after their production. In addition, different degradation mechanisms can often take place depending on the plastic composition and appropriate environmental and packaging conditions should be adopted. Therefore, methods for in situ and rapid characterization of plastic artifacts’ composition are greatly needed to outline proper conservation strategies. Infrared (IR) spectroscopy, such as attenuated total reflection Fourier transform infrared spectroscopy (ATR–FTIR), is a well-established method for polymeric material analysis. However, ATR-FTIR requires an intimate contact with the object, which makes its application less appropriate for the in situ investigation of fragile or brittle degraded plastic objects. Mid-FTIR reflectance spectroscopy may represent a valid alternative as it allows in situ measurements with minimum or even no contact, and IR data can be acquired rapidly. On the other hand, spectral interpretation of reflectance spectra is usually difficult as IR bands may appear distorted with significant changes in band maximum, shape and relative intensity, depending on the optical properties and surface texture of the material analyzed. Presently, mid-FTIR reflection devices working in external reflection (ER-FTIR) and diffuse reflection (DRIFT) modes have been used in cultural heritage research studies. As the collected vibrational information depends on the optical layout of the measuring system, differences between ER-FTIR and DRIFT spectra are thus expected when the same polymer is analyzed. So far, ER-FTIR and DRIFT spectroscopy have been individually explored for the identification of plastic objects, but comparative studies between the application of two reflectance FTIR modes have not been presented yet. In this work, the use of two portable FTIR spectrometers equipped with ER-FTIR and DRIFT modes were compared for plastics identification purposes for the first time. Both references of polymeric materials and historical plastic objects (from a Portuguese private collection) were studied and the differences between ER-FTIR and DRIFT spectra were discussed. The spectra features were examined considering the two different optical geometries and analytes’ properties. This new insight can support a better understanding of both vibrational information acquired and practical aspects in the application of the ER-FTIR and DRIFT in plastic analysis.


2017 ◽  
Vol 32 (1) ◽  
pp. 117-129 ◽  
Author(s):  
R. Alberti ◽  
V. Crupi ◽  
R. Frontoni ◽  
G. Galli ◽  
M. F. La Russa ◽  
...  

A variety of fragments of frescoes coming from the Villa dei Quintili in Rome and dating back to the II century A.D. were subjected to, first of all, an X-ray fluorescence (XRF) analysis by optimizing a portable spectrometer for non-destructive investigation in the field of cultural heritage.


Author(s):  
S. Naka ◽  
R. Penelle ◽  
R. Valle

The in situ experimentation technique in HVEM seems to be particularly suitable to clarify the processes involved in recrystallization. The material under investigation was unidirectionally cold-rolled titanium of commercial purity. The problem was approached in two different ways. The three-dimensional analysis of textures was used to describe the texture evolution during the primary recrystallization. Observations of bulk-annealed specimens or thin foils annealed in the microscope were also made in order to provide information concerning the mechanisms involved in the formation of new grains. In contrast to the already published work on titanium, this investigation takes into consideration different values of the cold-work ratio, the temperature and the annealing time.Two different models are commonly used to explain the recrystallization textures i.e. the selective grain growth model (Beck) or the oriented nucleation model (Burgers). The three-dimensional analysis of both the rolling and recrystallization textures was performed to identify the mechanismsl involved in the recrystallization of titanium.


2017 ◽  
Vol 72 (6) ◽  
pp. 355-364
Author(s):  
A. Kopp ◽  
T. Bernthaler ◽  
D. Schmid ◽  
G. Ketzer-Raichle ◽  
G. Schneider

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