Combining Atomistic Simulation and X-ray Diffraction for the Characterization of Nanostructures: A Case Study on Fivefold Twinned Nanowires

ACS Nano ◽  
2014 ◽  
Vol 8 (2) ◽  
pp. 1629-1638 ◽  
Author(s):  
Florian Niekiel ◽  
Erik Bitzek ◽  
Erdmann Spiecker
Heritage ◽  
2018 ◽  
Vol 1 (2) ◽  
pp. 468-478 ◽  
Author(s):  
Fernanda Carvalho ◽  
Andreia Lopes ◽  
Antonella Curulli ◽  
Teresa da Silva ◽  
Maria Lima ◽  
...  

Good conservation and restoration practices of cultural heritage assets rely on the knowledge of original materials. In the framework of the HERACLES Project (HERACLES—HEritage Resilience Against CLimate Events on Site, H2020 Grant Agreement 700395), dealing with the effects of climatic actions and natural hazards on built heritage, a set of important heritage sites are currently under study to improve their resilience against climate events. Among these are the medieval Gubbio Town Walls in Italy. The present work focuses on the mortars and binders of this monument and collected samples related to different parts of the Walls, corresponding to various historical periods of construction and interventions. They were characterized to determine their minerochemical composition, thermal behavior, and morphology. For that purpose, ex-situ laboratory techniques, such as X-ray diffraction (XRD), wavelength dispersive X-ray fluorescence (WDXRF), optical microscopy (OM), polarized light microscopy (PLM), scanning electron microscopy (SEM), and simultaneous differential thermal analysis and thermogravimetry (TG-DTA) were used to discern trends in different sampling areas due to construction/reconstruction periods and building techniques.


2014 ◽  
Vol 979 ◽  
pp. 440-443
Author(s):  
W. Siriprom ◽  
K. Teanchai ◽  
S. Kongsriprapan ◽  
J. Kaewkhao ◽  
N. Sangwaranatee

The chemical and physical properties of topsoil and subsoil which collected from the cassava cropping area in Chonburi Province have been investigated. The characterization of both soil sample were used X-Ray Diffraction (XRD), Energy Dispersive X-Ray Fluorescence (EDXRF) while FTIR used to confirmed the formation of intermolecular bonding and Thermo-Gravimetric Analysis (TGA) used for investigated the crystalline. It was found that, the XRD pattern indicated quartz phase. The chemical composition by XRF reported that the soils samples consist of Si, Al, Ca, Fe, K, Mn, Ti, Cr, Zn, Ag and Cu. and TGA results, noticed that the removal of moisture and organics material.


Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3908
Author(s):  
Laura Teodorescu ◽  
Ayed Ben Amara ◽  
Nadia Cantin ◽  
Rémy Chapoulie ◽  
Cătălin Ducu ◽  
...  

Combined analysis methods such as optical microscopy (OM), cathodoluminescence (CL) microscopy, X-ray diffraction (XRD), and scanning electron microscopy–energy dispersive X-ray spectrometry (SEM–EDX) have made it possible to obtain the first physico-chemical data of Dacian potsherds, exhumed at the archeological site of Ocnița-Buridava, Romania; the samples were provided by the “Aurelian Sacerdoțeanu” County Museum Vâlcea, dating from the 2nd century BC to the 1st century AD. The mineralogical and petrographic analyses revealed two types of ceramic pastes, taking into account the granulometry of the inclusions and highlighting the choice of the potter for fabricating the ceramic either by wheel or by hand. All samples showed an abundance in quartz, mica (muscovite and biotite), and feldspars. These observations were confirmed by cathodoluminescence imagery, revealing heterogeneous pastes with varied granulometric distributions. The XRD patterns indicated the presence of the mineral phases, indicating a firing temperature below 900 °C. The wheel-made ceramics have a fine, compact matrix with very fine inclusions (<40 µm). On the other hand, the hand-made ceramics present a coarse matrix, with inclusions whose granulometry reaches approximately 2 mm. The difference between these two types of ceramics is also confirmed by the mineralogical and chemical analysis. The wheel-made potsherds are more abundant in MgO, Al2O3, and CaO contents.


2018 ◽  
Vol 15 (30) ◽  
pp. 290
Author(s):  
Guadalupe Do Nascimento Campos ◽  
Marcus Granato ◽  
Antonieta Middea ◽  
Ricardo Tadeu Lopes

O presente trabalho apresenta alguns dos resultados obtidos no âmbito do projeto de pesquisa Conservação e Caracterização Microanalítica de Objetos Arqueológicos Metálicos, desenvolvido no Museu de Astronomia e Ciências Afins - MAST. O projeto tem como objetivo principal estabelecer metodologias de caracterização e conservação do patrimônio arqueológico metálico. Os artefatos selecionados para o estudo de caso são provenientes do Sítio Funerário da Igreja São Gonçalo Garcia (região central do Rio de Janeiro), relacionados aos séculos XVIII e XIX. Para os exames arqueométricos, foram empregadas as seguintes técnicas de caracterização: radiografia digital e microtomografia computadorizada de raios X, microscopias estereoscópica e eletrônica de varredura, espectroscopia de energia dispersiva (MEV/EDS) e difratometria de raios X. Foram obtidas informações sobre a composição dos artefatos (fase metálica e alguns produtos de corrosão), detalhes da morfologia em 3D não visíveis a olho nu, extensão da mineralização, dentre outros aspectos.  Abstract: This paper presents some of the achieved results in the "Microanalytical Conservation and Characterization of Metallic Archaeological Objects" research project, developed at the Museum of Astronomy and Related Sciences - MAST. The project's main goal is to establish methodologies for characterization and conservation of the metallic archaeological heritage. The artifacts selected for the case study are from the Funeral Site at São Gonçalo Garcia's Church (Rio de Janeiro's central region), related to the 18th and 19th centuries. For the archaeometric examinations, the following characterization techniques were employed: digital radiography and X ray microtomography, stereoscopic and scanning electron microscopy, energy-dispersive X ray spectroscopy (SEM / EDS) and X ray diffraction. Results were obtained about the artifacts's composition (metallic phase and some corrosion products), 3D morphology details invisible to the naked eye, and the extent of the mineralization, among other aspects.


ACTA IMEKO ◽  
2017 ◽  
Vol 6 (3) ◽  
pp. 71 ◽  
Author(s):  
Jasper Rikkert Plaisier ◽  
Luca Nodari ◽  
Lara Gigli ◽  
Elena Paz Rebollo San Miguel ◽  
Renzo Bertoncello ◽  
...  

<p class="Abstract"><span lang="EN-US">The MCX beamline at the synchrotron Elettra is the general purpose diffraction beamline that is well suited for non-destructive and innovative X-ray diffraction (XRD) experiments in the field of cultural heritage. The experimental station houses a large number of instruments facilitating a range of different types of analysis. Recently, a comprehensive study of the alteration products in grisaille paints was performed at the beamline. This type of analysis is very important to understand the complex processes involved in the deterioration of this type of glass decoration. An exhaustive characterization of these products and so a full understanding of the mechanism of their formation may lead to the development of new protective materials for conservation and restoration. XRD experiments at the MCX beamline allowed us to recognize the alteration products on the grisailles surface and to propose a mechanism for the formation of alteration patina. Here we present the beamline, its instrumentation and its capabilities by showing an example of the study on grisaille paints. </span></p>


Author(s):  
R. E. Herfert

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.


Author(s):  
W. W. Barker ◽  
W. E. Rigsby ◽  
V. J. Hurst ◽  
W. J. Humphreys

Experimental clay mineral-organic molecule complexes long have been known and some of them have been extensively studied by X-ray diffraction methods. The organic molecules are adsorbed onto the surfaces of the clay minerals, or intercalated between the silicate layers. Natural organo-clays also are widely recognized but generally have not been well characterized. Widely used techniques for clay mineral identification involve treatment of the sample with H2 O2 or other oxidant to destroy any associated organics. This generally simplifies and intensifies the XRD pattern of the clay residue, but helps little with the characterization of the original organoclay. Adequate techniques for the direct observation of synthetic and naturally occurring organoclays are yet to be developed.


2018 ◽  
Vol 2 (1) ◽  
pp. 7
Author(s):  
S Chirino ◽  
Jaime Diaz ◽  
N Monteblanco ◽  
E Valderrama

The synthesis and characterization of Ti and TiN thin films of different thicknesses was carried out on a martensitic stainless steel AISI 410 substrate used for tool manufacturing. The mechanical parameters between the interacting surfaces such as thickness, adhesion and hardness were measured. By means of the scanning electron microscope (SEM) the superficial morphology of the Ti/TiN interface was observed, finding that the growth was of columnar grains and by means of EDAX the existence of titanium was verified.  Using X-ray diffraction (XRD) it was possible to observe the presence of residual stresses (~ -3.1 GPa) due to the different crystalline phases in the coating. Under X-ray photoemission spectroscopy (XPS) it was possible to observe the molecular chemical composition of the coating surface, being Ti-N, Ti-N-O and Ti-O the predominant ones.


Author(s):  
D. Nagasamy Venkatesh ◽  
S. Karthick ◽  
M. Umesh ◽  
G. Vivek ◽  
R.M. Valliappan ◽  
...  

Roxythromycin/ β-cyclodextrin (Roxy/ β-CD) dispersions were prepared with a view to study the influence of β-CD on the solubility and dissolution rate of this poorly soluble drug. Phase-solubility profile indicated that the solubility of roxythromycin was significantly increased in the presence of β-cyclodextrin and was classified as AL-type, indicating the 1:1 stoichiometric inclusion complexes. Physical characterization of the prepared systems was carried out by differential scanning calorimetry (DSC), X-ray diffraction studies (XRD) and IR studies. Solid state characterization of the drug β-CD binary system using XRD, FTIR and DSC revealed distinct loss of drug crystallinity in the formulation, ostensibly accounting for enhancement of dissolution rate.


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