Search results for "In situ analysis"
showing 7 items of 7 documents
A laboratory cave for the study of wall degradation in rock art caves : an implementation in the Vézère area
2013
The aim of this proposal is to present an original approach to the study and preservation of rock art caves. A multidisciplinary study of cave wall alteration will be performed to understand the impact of environmental context on the evolution of wall surfaces. The approach involves the choice of a cave with characteristics similar to painted caves in the studied area (Vézère Valley in Dordogne, France): e.g., cave wall alteration, lithology, morphology, etc. This selected cave is intended to become a laboratory cave, monitored for the acquisition of chemical, physical and biological environmental data on bedrock, air and fluids along with their characteristics. A cave without art or archae…
Reduced graphene oxide decorated with metals nanoparticles electrode as electrochemical sensor for dopamine
2019
Dopamine (DA) is one of the most important neurotransmitters that influences the processes that involve memory, sleep, mood, learning among others [1]. In fact, in the last years, dopamine concentration in human body fluids has been related to some neurodegenerative diseases, such as Parkinson and Alzheimer's diseases [2]. The possibility to have a bio-marker for these disease is of extreme importance because, disease related with dementia, are diagnosed when they are already developed and their management become almost impossible. The possibility to continuously monitor DA level in fluids, such as blood and urine, could accelerate the early diagnosis of these diseases. The principal analyt…
Application of field portable EDXRF spectrometry to analysis of pigments of Levantine rock art
2010
The results of the analyses of elemental composition of red and black pigments of Levantine rock art from La Saltadora rock shelters (Valltorta gorge, Castellon, Spain) are presented in this paper. Nondestructive analyses were carried out using a portable energy dispersive X-ray fluorescence (EDXRF) spectrometer developed for in situ analysis. The results revealed the strong presence of calcium in all the analyzed locations due to the contribution of the underlying calcareous bedrock and the overlying crust. Iron is the main element detected in red pigments and manganese in black pigments. Iron and calcium ratios have been found indicative of the degree of preservation of the pictorial laye…
Validity of NMR pore-size analysis of cultutal heritage ancient building materials containing magnetic impurities
2007
NMR relaxation time distributions, obtained with laboratory and portable devices, are utilized to characterize the pore-size distributions of building materials coming from the Roman remains of the Greek-Roman Theatre of Taormina. To validate the interpretation of relaxation data in terms of pore-size distribution, comparison of results from standard and in situ NMR experiments with results of the mercury intrusion porosimetry (MIP) has been made. Although the pore-size distributions can be obtained by NMR in terms of either longitudinal (T-1) or transverse (T-2) relaxation times distributions, the shorter duration of the T-2 measurement makes it, in principle, preferable, although the dete…
Double pulse laser induced breakdown spectroscopy applied to natural and artificial materials from cultural heritages
2009
Abstract The laser-induced breakdown spectroscopy (LIBS) is an applied physical technique that has shown in recent years its great potential for rapid qualitative analysis of materials. Thanks to the possibility to implement a portable instrument that perform LIBS analysis, this technique is revealed to be particularly useful for in situ analysis in the field of cultural heritages. The purpose of this work is to evaluate the potentiality of LIBS technique in the field of cultural heritages, with respect to the chemical characterization of complex matrix as calcareous and refractory materials for further quantitative analyses on cultural heritages. X-Ray Fluorescence (XRF) analyses were used…
Simultaneous detection of copper and mercury in water samples using in-situ pH control with electrochemical stripping techniques
2023
The performance of electrochemical sensors using an in situ pH control technique for detection of mercury and copper in neutral solutions is described herein. Sensors are comprised of two distinct parallel gold interdigitated microband electrodes each of which may be polarised separately. Biasing one interdigitated “protonator” electrode sufficiently positive to begin water electrolysis, resulted in the production of H+ ions, which, consequently droped the interfacial pH at the other second interdigitated “sensing” electrode. This decrease in pH permitted the electrodeposition (and consequent stripping) of metals at a sensing electrode without the need to acidify the whole test solution. In…
In situ analysis with portable Raman and ED-XRF spectrometers for the diagnosis of the formation of efflorescence on walls and wall paintings of the …
2014
This work presents the results of field Raman analyses, assisted by a hand-held energy dispersive X-ray fluorescence spectrometer, for the experimental determination of efflorescence from walls and wall paintings of two Pompeian houses, one with many luxurious decorative elements (House of Marcus Lucretius, Regio IX, Insula 3, House 5/24) and a more modest building (Regio IX, Insula 3, House 1-2). Both exposed and protected rooms were measured in different year seasons, spring (May 2010) and summer (September 2011 and 2012) and considering different orientations. Chemical attacks of acid gases (CO2, SO2 and NOx) on the original compounds of the mortars, biominerals formed by the biological …