Mineralogical characterization of diamonds from Roosevelt Indigenous Reserve, Brazil, using non-destructive methods

Lithos ◽  
2016 ◽  
Vol 265 ◽  
pp. 182-198 ◽  
Author(s):  
M.P.A.C. Borges ◽  
M.A. Moura ◽  
S.L.R. Lenharo ◽  
C.B. Smith ◽  
D.P. Araujo
1985 ◽  
Vol 29 ◽  
pp. 345-352 ◽  
Author(s):  
D. K. Bowen ◽  
S.T. Davies ◽  
S. Swaminathan

An extensive programme of characterization of optoelectronic device material has been performed at the Synchrotron Radiation Source, Baresbury Laboratory, in collaboration with Plessey Research, Caswell. The material was grown by Plessey Research by liquid phase epitaxy on InP substrates and had quaternary active layers with, usually, four epilayers in total. Some specimens had graded epilayers. This paper reports use of the methods of double crystal topography, rocking curve analysis and simulation, selective etching and Talysurf measurement in order to develop and assess non-destructive methods of evaluation. The destructive methods above were therefore used in order to test and verify the non-destructive X-ray techniques.


Crystals ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 708
Author(s):  
Auxiliadora Gómez-Morón ◽  
Pilar Ortiz ◽  
Rocio Ortiz ◽  
Francesco Colao ◽  
Roberta Fantoni ◽  
...  

A multi-approach study has been designed to evaluate the mannerist-style masterpiece of the Christ of the Expiration (Museum Brotherhood, Seville, Spain), a polychrome wooden paste sculpture of the 16th Century that was restored in the Andalusian Historical Heritage Institute (IAPH). During its intervention, a combination of two non-destructive prototypes were used to evaluate the different color in its feet regarding its legs and torso and its cause. A portable equipment that combined X-ray diffraction (XRD) and X-ray fluorescence (XRF) was employed to analyze chemical composition and mineralogical characterization of pigments. This equipment allowed obtaining simultaneously XRF and XRD at the same point without sampling. X-ray techniques identified cerussite, hydrocerussite and barite in different layers. The presence of zinc oxide from a recent restoration was also detected. Additionally, laser induced fluorescence (LIF) was employed to assess the presence of different fluorescent compounds on the surface. This technique showed the use of acrylic products in the feet, loincloth and torso of Christ from previous restoration and allowed to detect spectral difference on the feet and a high ration of the acrylic product on feet, both could be the cause of the differential degradation between the feet and torso. This multi-approach study based on portable and non-destructive techniques allowed restoration monitoring and helped restorers to take decisions without sampling.


2016 ◽  
Author(s):  
Yan Liu ◽  
Junliang Tao ◽  
Xinbao Yu ◽  
Zhen Liu ◽  
Xiong (Bill) Yu

Author(s):  
Khial Nassima ◽  
Rachid Mehaddene

The durability of reinforced concrete structures is reduced by the chloride penetration and susceptibility of the reinforcement to chloride induced corrosion which is considered a critical physic-chemical case. As the financial impact of the phenomena is very important, it seems essential to determine it influence on strength of reinforced concrete elements subjected to aggressive environnement such us the presence of chlorides when exposed to marine environnement. As such, the determination of the ion concentrations of chlorides profile within the cement matrix is of major importance, it tool to estimate the time required by the chlorides to reach the reinforcements in sufficient quantity to depassivate the steel.


2014 ◽  
Vol 624 ◽  
pp. 379-386 ◽  
Author(s):  
Elisa Galli ◽  
Marco Savoia ◽  
Camilla Colla ◽  
Daniele Ferretti

The aim of the work is to characterize mechanical and chemical properties of the mortar, and thus the masonry, of historical buildings damaged by the Emilia May 20-29th 2012 earthquakes. The attention was focused on historical strategic buildings, located in Modena district. The experimental campaign here reported was carried out for each building through four steps: first, a mechanical characterization of masonry was performed in situ using non-destructive and semi-destructive methods (step 1); then, some materials were collected in order to obtain standard specimens of mortar joint and brick (step 2). In laboratory, those samples were properly prepared for testing (step 3) with compression and flexural test setups; finally, a limited number of those mortar samples were tested in order to obtain their chemical properties (step 4). The in-situ and laboratory test results were separately elaborated for mortar and brick, to characterize the single masonry components. The results were then used to estimate the characteristic masonry parameters. Criteria to obtain the masonry behavior were reviewed in order to give the average masonry parameters. The characteristic and average values of compression strength were compared with ranges provided in the codes for the same masonry typology.


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