scholarly journals Innovative nanomaterials for bone remains consolidation: performance evaluation and impact on 14C dating and on palaeogenetic analysis

2022 ◽  
Author(s):  
Francesca Porpora ◽  
Valentina Zaro ◽  
Lucia Liccioli ◽  
Alessandra Modi ◽  
Arianna Meoli ◽  
...  
Keyword(s):  
Radiocarbon Dating ◽  
Multidisciplinary Approach ◽  
X Ray Diffraction ◽  
Mineral Density ◽  
14C Dating ◽  
Substantial Impact ◽  
X Ray ◽  
Ancient Bone ◽  
Set Up ◽  
Bone Remains

Abstract An innovative protocol for the consolidation of ancient bone remains based on the use of nanometric hydroxyapatite (HAP) was set up and tested through a multidisciplinary approach. A new protocol for the synthesis of HAP nanoparticles was developed, and the composition of the obtained nanomaterial were investigated through Fourier Transform Infrared Spectroscopy (FTIR) and X-Ray Diffraction (XRD); sizes, shape and morphology of the synthesized particles were studied by Scanning Electron Microscopy (SEM). The consolidation performance was evaluated by testing the new nanomaterial on degraded ancient bone findings. An increase of the mineral density and of the micro-hardness of the bone were observed. The new consolidation method was also tested to assess possible effects on the palaeogenetic analysis and radiocarbon dating on the treated bones. The consolidation treatment has no substantial impact on the genetic characterisation of the skeletal remains and does not introduce any contaminations that could affect radiocarbon dating. This consolidation procedure represents a more compatible conservation tool with respect to traditional procedures: it has been shown that the treatment is effective, easily-applicable and not detrimental for 14C dating and palaeogenetic analysis.

Evaluation of Freezing Methods by Low Temperature X-Ray Diffraction

1977 ◽  
Vol 35 ◽  
pp. 330-333
Author(s):  
T. Gulik-Krzywicki ◽  
M.J. Costello
Keyword(s):  
Biological Materials ◽  
Molecular Organization ◽  
X Ray Diffraction ◽  
Glass Capillary ◽  
X Ray ◽  
Rate Dependent ◽  
Before And After ◽  
Freeze Etching ◽  
Diffraction Patterns ◽  
Set Up

Freeze-etching electron microscopy is currently one of the best methods for studying molecular organization of biological materials. Its application, however, is still limited by our imprecise knowledge about the perturbations of the original organization which may occur during quenching and fracturing of the samples and during the replication of fractured surfaces. Although it is well known that the preservation of the molecular organization of biological materials is critically dependent on the rate of freezing of the samples, little information is presently available concerning the nature and the extent of freezing-rate dependent perturbations of the original organizations. In order to obtain this information, we have developed a method based on the comparison of x-ray diffraction patterns of samples before and after freezing, prior to fracturing and replication.Our experimental set-up is shown in Fig. 1. The sample to be quenched is placed on its holder which is then mounted on a small metal holder (O) fixed on a glass capillary (p), whose position is controlled by a micromanipulator.

Large-scale and facile fabrication of PbSe nanostructures by selenization of a Pb sheet

2015 ◽  
Vol 08 (05) ◽  
pp. 1550063 ◽  
Author(s):  
Sara Hoomi ◽  
Ramin Yousefi ◽  
Farid Jamali-Sheini ◽  
Abdolhossein Sáaedi ◽  
Mohsen Cheraghizade ◽  
...  
Keyword(s):  
Large Scale ◽  
Chemical Vapor ◽  
Infrared Region ◽  
Photoelectron Spectra ◽  
X Ray Diffraction ◽  
X Ray ◽  
Facile Fabrication ◽  
Higher Temperature ◽  
Set Up ◽  
Lower Temperature

PbSe nanostructures were synthesized by selenization of lead sheets in a chemical vapor deposition (CVD) set-up under a selenium ambiance. The lead sheets were placed in the different temperature zones, between 300°C and 450°C. Field emission scanning electron microscope (FESEM) images showed that, PbSe nanostructures grown on the lead sheets with different morphologies. PbSe nanostructures with flakes shape were grown on the lead sheets that were placed in the lower temperature, while PbSe nanocubes and nanorods, which were grown on the nanocubes, were grown on the lead sheets in the higher temperature. The phase and composition of the product were identified by X-ray diffraction (XRD) pattern and X-ray photoelectron spectra (XPS). The XRD and XPS results showed that, the PbSe phase was started to form after 350°C and completed at 450°C. However, the XPS results showed that the Se concentration was different in the samples. In addition, Raman measurements confirmed the XRD and XPS results and indicated three Raman active modes, which belonged to PbSe phase for the nanostructures. The optical properties of the products were characterized by UV–Vis. The optical characterization results showed a band gap for the PbSe nanostructures in the infrared region.

scholarly journals Archaeometric Characterisation of Decorated Pottery from the Archaeological Site of Villa dei Quintili (Rome, Italy): Preliminary Study

Geosciences ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 172 ◽  
Author(s):  
Michela Ricca ◽  
Giuseppe Paladini ◽  
Natalia Rovella ◽  
Silvestro Antonio Ruffolo ◽  
Luciana Randazzo ◽  
...  
Keyword(s):  
Multidisciplinary Approach ◽  
Raw Materials ◽  
Archaeological Site ◽  
Optical Microscope ◽  
X Ray Diffraction ◽  
X Ray ◽  
Geochemical Study ◽  
Renaissance Period ◽  
Preliminary Study ◽  
Materials Used

This work focused on the study of decorated pottery dated back to the 16th century from the Roman archaeological site of Villa dei Quintili, a monumental complex located in the south-eastern part of Rome (Italy). A minero-petrographic and geochemical study was undertaken to analyse five archaeological samples in order to define textural features and raw materials used for their production, along with the chemical and physical composition of the superficial decorative glazed coatings. For this purpose, different analytical methods were used, such as polarising optical microscope (POM), X-ray diffraction (XRD), micro-Raman spectroscopy, X-Ray fluorescence (XRF), and electron microprobe analysis coupled with energy dispersive spectrometry (EMPA-EDS). The results of such a multidisciplinary approach allowed us to achieve important results crucial to recognise the shards as majolica of the Renaissance period, improving knowledge about manufacturing processes of these renowned painted ceramic artefacts.

Synthesis and Structural Characterization of Ca14NbxIn1-xAs11 (x ≈ 0.85)

2016 ◽  
Vol 257 ◽  
pp. 147-151 ◽  
Author(s):  
Yi Wang ◽  
Svilen Bobev
Keyword(s):  
Physical Properties ◽  
Side Reaction ◽  
Structure Type ◽  
Major Product ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ongoing Work ◽  
Set Up

Single-crystals of the new compound Ca14NbxIn1–xAs11 have been obtained from a solid-state reaction in a sealed Nb ampoule. The initial experiment had been set up with the aim to investigate the effect of electron doping (via In) on the crystal structure and physical properties of Ca14MnAs11. Subsequent single-crystal X-ray diffraction and elemental analysis work suggested that instead of Ca14MnxIn1–xAs11, the major product of the reaction is the phase Ca14NbxIn1–xAs11. This supposition was corroborated when the title compound was synthesized from a reaction of Ca, In and As in a sealed Nb ampoule, proving that, 1) Mn metal is not included in the structure, and 2) that the inadvertent side reaction of As with the walls of the Nb container is the source of the niobium. The overall structure is isotypic with the tetragonal Ca14AlSb11 structure type (space group I41/acd), although some marked differences between the two must be noted. Current ongoing work is focused on the synthesis of phase pure polycrystalline samples and determination of the physical properties of this unusual transition metal Zintl phase.

scholarly journals High-Throughput Crystallization Pipeline at the Crystallography Core Facility of the Institut Pasteur

Molecules ◽  
2019 ◽  
Vol 24 (24) ◽  
pp. 4451 ◽  
Author(s):  
Patrick Weber ◽  
Cédric Pissis ◽  
Rafael Navaza ◽  
Ariel E. Mechaly ◽  
Frederick Saul ◽  
...  
Keyword(s):  
High Throughput ◽  
Sequence Data ◽  
Data Bank ◽  
Whole Genome Sequence ◽  
Whole Genome ◽  
X Ray Diffraction ◽  
Sequencing Technology ◽  
X Ray ◽  
Set Up ◽  
General User

The availability of whole-genome sequence data, made possible by significant advances in DNA sequencing technology, led to the emergence of structural genomics projects in the late 1990s. These projects not only significantly increased the number of 3D structures deposited in the Protein Data Bank in the last two decades, but also influenced present crystallographic strategies by introducing automation and high-throughput approaches in the structure-determination pipeline. Today, dedicated crystallization facilities, many of which are open to the general user community, routinely set up and track thousands of crystallization screening trials per day. Here, we review the current methods for high-throughput crystallization and procedures to obtain crystals suitable for X-ray diffraction studies, and we describe the crystallization pipeline implemented in the medium-scale crystallography platform at the Institut Pasteur (Paris) as an example.

Shock Wave Compression of NaCl Single Crystals observed by Flash-X-Ray Diffraction

1978 ◽  
Vol 33 (8) ◽  
pp. 918-923 ◽  
Author(s):  
F. Müller ◽  
E. Schulte
Keyword(s):  
Shock Wave ◽  
Single Crystals ◽  
Observation Time ◽  
Plane Shock ◽  
X Ray Diffraction ◽  
X Ray ◽  
Wave Compression ◽  
Shock Wave Compression ◽  
Diffraction Patterns ◽  
Set Up

Flash-x-ray-diffraction patterns (FXD) with an exposure time of 4 ns of NaCl single crystals compressed by plane shock waves are obtained at pressures of about 30 kbar. From the diffraction patterns the compression is determined and compared with Hugoniot data. During shock load the lattice shows an uniaxial compression. While in case of measurements at the free surface an observation time of only a few nanoseconds is available, this experimental set-up allows an observation time of two microseconds.

A simple technique to control macromolecular crystal nucleation efficiently using a standard vapour-diffusion setup

2000 ◽  
Vol 33 (3) ◽  
pp. 988-989 ◽  
Author(s):  
Luca Jovine
Keyword(s):  
Data Collection ◽  
Diffraction Analysis ◽  
Vapour Pressure ◽  
Simple Technique ◽  
Crystal Nucleation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Vapour Diffusion ◽  
Discrete Amount ◽  
Set Up

Excessive nucleation often leads to a large number of small macromolecular crystals that are not useful for X-ray diffraction analysis. Crystals with dimensions suitable for data collection can be reproducibly obtained by releasing, for a discrete amount of time, the vapour pressure in both hanging- and sitting-drop experiments, set up at lower precipitant concentrations than those required for crystallization.

Kinetics of high-pressure mineral phase transformations using in situ time-resolved X-ray diffraction in the Paris-Edinburgh cell: a practical guide for data acquisition and treatment

2008 ◽  
Vol 72 (2) ◽  
pp. 683-695 ◽  
Author(s):  
J. P. Perrillat
Keyword(s):  
High Pressure ◽  
Phase Transformations ◽  
Kinetic Studies ◽  
X Ray Diffraction ◽  
Time Resolved ◽  
X Ray ◽  
Practical Guide ◽  
Set Up ◽  
Isothermal Kinetic

AbstractSynchrotron X-ray diffraction (XRD) is a powerful technique to study in situ and in real-time the structural and kinetic processes of pressure-induced phase transformations. This paper presents the experimental set-up developed at beamline ID27 of the ESRF to perform time-resolved angle dispersive XRD in the Paris-Edinburgh cell. It provides a practical guide for the acquisition of isobaric-isothermal kinetic data and the construction of transformation-time plots. The interpretation of experimental data in terms of reaction mechanisms and transformation rates is supported by an overview of the kinetic theory of solid-solid transformations, with each step of data processing illustrated by experimental results of relevance to the geosciences. Reaction kinetics may be affected by several factors such as the sample microstructure, impurities or differential stress. Further high-pressure kinetic studies should investigate the influence of such processes, in order to acquire kinetic information more akin to natural or technological processes.

Laboratory set-up for X-ray diffraction at high pressures

2011 ◽  
Vol 31 (4) ◽  
pp. 611-619 ◽  
Author(s):  
Catalin Popescu ◽  
Loreynne Pinsard-Gaudart ◽  
Nita Dragoe
Keyword(s):  
High Pressures ◽  
X Ray Diffraction ◽  
X Ray ◽  
Set Up

High Density Bulk Shape Rapid Consolidation of the Yba2Cu307-X Superconductor

1989 ◽  
Vol 169 ◽  
Author(s):  
S. V. Rele ◽  
R. V. Raman ◽  
H. S. Meeks ◽  
R. L. Anderson ◽  
R. N. Shelton ◽  
...  
Keyword(s):  
Volume Fraction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Superconducting Volume Fraction ◽  
One Step ◽  
Hollow Cylinders ◽  
Diffraction Patterns ◽  
Set Up ◽  
Cylinders And Spheres ◽  
High Processing

AbstractA novel rapid densification technique for fabrication of bulk shape YBa2Cu307–xsuperconductor is presented. The Ceracon process is a one‐step, quasi‐isostatic consolidation route utilizing conventional P/M equipment and set‐up. The Ceracon technology has enabled successful fabrication of bulk, shapes such as discs, cylinders, hollow cylinders and spheres along with significant increases in the density up to 95‐98% of the theorertical. The superconducting volume fraction is preserved due to short hold times at the operating temperatures and avoidance of high processing temperatures. Results based on densities, microstructure, susceptibility measurements, X‐ray diffraction patterns and TGA measurements are discussed.

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