Health detection techniques for historic structures

2021 ◽  
Vol 63 (9) ◽  
pp. 855-864
Author(s):  
Dong Luo ◽  
Shangwei Wang ◽  
Xiaohong Du ◽  
Peng Zhao ◽  
Tian Lu ◽  
...  

Abstract The protection of historic buildings has drawn increasing attention and usually requires a sound nondestructive testing (NDT) technique. This paper first describes the significance of and the status on the protection of historic structures followed by a summary of common damage and repair measures for such structures. Lastly, the principles, characteristics, and applications of NDT techniques for historic wooden and masonry structures, including ultra-CT testing, stress wave testing, micro-drilling resistance meter, radar detection, and X-ray diffraction, are described and compared. This study concludes by providing a guide for studying the structural damage of historic structures and for the selection of a detection technique.

2005 ◽  
Vol 876 ◽  
Author(s):  
Patrick Huber ◽  
Klaus Knorr

AbstractWe present a selection of x-ray diffraction patterns of spherical (He, Ar), dumbbell- (N2, CO), and chain-like molecules (n-C9H20, n-C19H40) solidified in nanopores of silica glass (mean pore diameter 7nm). These patterns allow us to demonstrate how key principles governing crystallization have to be adapted in order to accomplish solidification in restricted geometries. 4He, Ar, and the spherical close packed phases of CO and N2 adjust to the pore geometry by introducing a sizeable amount of stacking faults. For the pore solidified, medium-length chainlike n-C19H40 we observe a close packed structure without lamellar ordering, whereas for the short-chain C9H20 the layering principle survives, albeit in a modified fashion compared to the bulk phase.


Minerals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 311 ◽  
Author(s):  
Graciela Ponce-Antón ◽  
Maria Cruz Zuluaga ◽  
Luis Angel Ortega ◽  
Juantxo Agirre Mauleon

Mortars from the cistern in Amaiur Castle (Navarre, Spain) were analysed to assess the mortar manufacturing process and application techniques. To this end, optical microscopy, scanning electron microscopy (SEM), thermogravimetric analysis, X-ray fluorescence (XRF), X-ray diffraction (XRD), Raman microspectroscopy, and Fourier transform infrared spectroscopy (FTIR) were performed. The study of both structural and plaster mortars from Amaiur Castle cistern show patterns/rules in the mortar manufacture according to the specific construction requirements. A multilayer application technique was used for the construction of the cistern tank. Deliberate selection of the aggregate nature and grading contributed to mortar impermeability. Ceramic and silico-aluminous rock fragments were used as aggregates in the cistern tank to confer hydraulicity to the mortars, instead of carbonated aggregates as used in the vault. Aluminosilicated phases present in the aggregates led to the formation of amesite, which is a magnesium aluminosilicate hydrate (M-A-S-H) phase conferring hydraulicity to the mortar. Two types of additives were identified in the outer pigmented layer of plaster. Beeswax was the identified organic additive used to improve the impermeability of mortar, while hematite was the identified inorganic additive giving rise to the reddish colour of the layer.


2002 ◽  
Vol 743 ◽  
Author(s):  
A. Usikov ◽  
O. V. Kovalenkov ◽  
M. M. Mastro ◽  
D. V. Tsvetkov ◽  
A. I. Pechnikov ◽  
...  

ABSTRACTThe structural, optical, and electrical properties of HVPE-grown GaN-on-sapphire templates were studied. The c and a lattice constants of the GaN layers were measured by x-ray diffraction. It was observed that the c and a lattice constants vary non-monotonically with Si-doping. The proper selection of Si-doping level and growth conditions resulted in controllable strain relaxation, and thus, influenced defect formation in GaN-on-sapphire templates. It was also observed that HVPE homoepitaxial GaN layers grown on the templates have better crystal quality and surface morphology than the initial templates.


1988 ◽  
Vol 3 (1) ◽  
pp. 32-38 ◽  
Author(s):  
David G. Cameron ◽  
Ernest E. Armstrong

AbstractFourier transform methods of smoothing and interpolation are applied to X-ray diffraction data. It is shown that, frequently, too small a step size is used. Major gains are to be expected by selection of the optimum step size and use of these methods.A comparison of Fourier transforms of diffractograms of quartz measured between 67 and 69° 2θ, collected at varying step intervals (0.1 to 0.01° 2θ) was used to illustrate these applications. By examining the Fourier transform of the diffractogram and noting where it decays to die baseline, a reasonable estimate of the optimal step interval can be obtained. In addition, Fourier interpolation can be used to enhance the appearance of the diffractogram, approximating a continuous plot.


2013 ◽  
Vol 634-638 ◽  
pp. 3498-3501
Author(s):  
Zheng Yao Li ◽  
Xiao Fan Guo ◽  
Jun Liu ◽  
Li Li Wang ◽  
Heng Qian Li

The characteristics of process mineralogy of the some lead-zinc mine were studied with scanning electron microscope, optics microscopes,and x-ray diffraction. The species of lead minerals and zinc minerals and the chemical composition of the minerals were analyzed. The liberations at different grinding finenesses and the particle sizes of the minerals had been also determined. The phase shape of lead and zinc in the ore was also analyzed. The behaviors of various minerals and mineralogical factors affecting the flotation had been explained clearly. The investigation results were favorable to reasonable selection of flotation parameters and would provide theoretical guidance to lead-zinc separation.


2010 ◽  
Vol 62 ◽  
pp. 70-75
Author(s):  
Nathalie Poirot ◽  
Philippe Boy ◽  
Philippe Belleville ◽  
Luc Bianchi

Scandium oxides nanopowders have been synthesized using a sol-gel route. ScOOH nanoparticles have been first prepared in solution using ScCl3, xH2O as precursor. Influence of pH and reflux time on particles size and shape has been studied. Sc2O3 nanoparticles were then obtained after ScOOH sol drying. Sols were characterized by laser granulometry, thermogravimetry and differential analysis (TGA- DSC). Depending on pH, 40 to 1000 nm size ScOOH particles can be obtained. At a given pH, the reflux time duration also influences the ScOOH particles size. The ScOOH sol can be used to prepare highly pure Sc2O3 nanopowders. X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Transmission Electron Microcopy (TEM), were used to characterize Sc203 nanopowders obtained from the various ScOOH solutions. The DSC and laser granulometry data indicate a strong relation between the nanoparticles size and the temperature of transformation of g-ScOOH to Sc2O3. Depending on the sol preparation various particles Sc2O3 size can then be obtained allowing the selection of the more suitable powder for transparent ceramic preparation.


2002 ◽  
Vol 57 (1-2) ◽  
pp. 129-134 ◽  
Author(s):  
Mario Faculty of Chemical Sciences, Unive ◽  
Paulina Hidalgo ◽  
Kazimierz Strzalka ◽  
Anna Kostecka-Gugala

The interaction of structurally different carotenoids with a membrane molecular model was examined by X-ray diffraction. The selected compounds were β-carotene, lycopene, lutein, violaxanthin, zeaxanthin, and additionally carotane, a fully saturated derivative of β-carotene. They present similarities and differences in their rigidity, the presence of terminal ionone rings and hydroxy and epoxy groups bound to the rings. The membrane models were multibilayers of dipalmitoylphosphatidylcholine (DPPC), chosen for this investigation because the 3 nm thickness of the hydrophobic core of its bilayer coincides with the thickness of the hydrophobic core of thylakoid membranes and the length of the carotenoid molecules. Results indicate that the six compounds induced different types and degrees of structural perturbations to DPPC bilayers in aqueous media. They were interpreted in terms of the molecular characteristics of DPPC and the carotenoids. Lycopene and violaxanthin induced the highest structural damage to the acyl chain and polar headgroup regions of DPPC bilayers, respectively.


2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
C. Marutoiu ◽  
S. P. Grapini ◽  
A. Baciu ◽  
M. Miclaus ◽  
V. C. Marutoiu ◽  
...  

The Evangelic Church in Bistriţa city is one of the important gothic monuments in Romania. Inside the church there have been preserved a series of furniture pieces from different centuries, and the stall that has been analysed in this study is one of them. The study presents the investigations that were made on the occasion of restoring the stall. The nature and the status of the wooden supports and also the composition of the painting layer which covers the front side of the stall were investigated by several methods: Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and differential scanning calorimetry (DSC) analyses. The back side of the stall was made of spruce fir wood and its status was also investigated. The nature of the component elements and the heritage value of the ensemble were also established.


2006 ◽  
Vol 981 ◽  
Author(s):  
Yann Leconte ◽  
Isabelle Monnet ◽  
Marc levalois ◽  
Magali Morales ◽  
Xavier Portier ◽  
...  

AbstractIn the context of research on new materials for next generation nuclear reactors, it becomes more and more interesting to know what can be the advantages of nanostructured materials for such applications. In this study, we performed irradiation experiments on microstructured and nanostructured â-SiC samples, with 95 MeV Xe and 4 MeV Au ions. The structure of the samples was characterized before and after irradiation by grazing incidence X ray diffraction and Raman spectroscopy. The results showed the occurrence of a synergy between electronic and nuclear energy loss in both samples with 95 MeV Xe ions, while the nanostructured pellet was found to have a better resistance to the irradiation with 4 MeV Au ions.


2016 ◽  
Author(s):  
Daniel Silva Barbutti ◽  
Roberto Carlos da Conceição Ribeiro

ResumoNeste estudo foram avaliadas as interações entre três representantes minerais constituintes das rochas ornamentais graníticas (quartzo, microclina e muscovita) e três protetivos comerciais com propriedades hidrorrepelentes. Os minerais foram caracterizados química e mineralogicamente por análises de fluorescência e difração de Raios-X (FRX e DRX, respectivamente), enquanto os protetivos foram caracterizados por meio de espectroscopia de infravermelho com transformada de Fourier (FTIR). Para avaliação da eficácia dos protetivos, foram realizados estudos de mobilidade eletroforética a partir da avaliação do potencial zeta dos minerais em função do pH, antes e após tratamento com cada produto. Os resultados indicaram melhor desempenho do protetivo a base de siloxano, reduzindo a eletronegatividade da superfície de todos os minerais, principalmente na faixa levemente ácida de pH entre 3 e 6, onde ocorrem os principais intemperismos capazes de alterar as propriedades físico-químicas de rochas expostas em centros urbanos. Foram visualizadas reduções médias de até 15mV para quartzo, 5 mV para muscovita e 20 mV para microclina. Análises prévias das rochas de um monumento e dos protetivos inicialmente elegidos para proteção são importantes para a correta conservação e restauro dos bens pétreos que resguardam seus valores artísticos e culturais. Palavras Chave: conservação e restauro, potencial zeta, mineral AbstractSURFACE CHEMISTRY STUDY FOR THE SELECTION OF HYDRORPEPEAL PROTEINS AND TECHNOLOGICAL SUPPORT FOR CONSERVATION AND RESTORATION OF STONE ASSETS. Interactions between the main minerals that compose the granitic dimension stones (quartz, microcline and muscovite) and three commercial hydrophobic protective coatings were investigated in this study. The minerals were characterized chemically and mineralogically through fluorescence X-ray analysis (XRF) and X-ray diffraction (XRD) respectively, while the protective coatings were characterized by Fourier transform infrared spectroscopy (FTIR). The interactions between minerals and protective coatings were evaluated by zeta potential measurements of the minerals as a function of pH before and after surface treatment with each product. The results showed that only one protective coating was able to reduce the electronegativity in all mineral samples, especially in mildly acidic pH range, where several outdoor weathering effects occur, modifying the physical and chemical properties of stone-built monuments in urban environment. Previous analysis of the stones that constitute the monument as well as preselected products for its treatment are considered important to guide the proper conservation and restoration of stone-built cultural heritages that enshrine their artistic and historical values. Keywords: conservation & restoration, zeta potential, mineral


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