scholarly journals Composition of Amphiboles in the Tremolite–Ferro–Actinolite Series by Raman Spectroscopy

Minerals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 491 ◽  
Author(s):  
Bersani ◽  
Andò ◽  
Scrocco ◽  
Gentile ◽  
Salvioli-Mariani ◽  
...  

Amphiboles are an important family of rock forming minerals, whose identification is crucial in provenance studies as well as in many other fields of geology, archaeology and environmental sciences. This study is aimed to find a quick way to characterize Ca-amphiboles in the tremolite (Ca2Mg5Si8O22(OH)2)–ferro–actinolite (Ca2Fe5Si8O22(OH)2) series. Raman spectroscopy is established as technique to perform non-destructive and quick analysis, with micrometric resolution, able to give the composition in terms of Mg/(Mg + Fe2+) ratio. To exploit the method, a preliminary characterization is performed by Scanning Electron Microscopy coupled with Energy-dispersed X-ray Spectroscopy (SEM-EDS). Two independent methods to evaluate the composition from the Raman data (aiming to an accuracy of about 5%), using the low-wavenumbers part of the spectrum and the OH stretching bands, are developed. The application of the proposed method to micro-Raman mappings and the possible use of handheld Raman spectroscopy to have compositional information on Ca-amphiboles are discussed.

2014 ◽  
Vol 10 ◽  
pp. 1613-1619 ◽  
Author(s):  
Simon Rondeau-Gagné ◽  
Jules Roméo Néabo ◽  
Maxime Daigle ◽  
Katy Cantin ◽  
Jean-François Morin

The synthesis and self-assembly of two new phenylacetylene macrocycle (PAM) organogelators were performed. Polar 2-hydroxyethoxy side chains were incorporated in the inner part of the macrocycles to modify the assembly mode in the gel state. With this modification, it was possible to increase the reactivity of the macrocycles in the xerogel state to form polydiacetylenes (PDAs), leading to a significant enhancement of the polymerization yields. The organogels and the PDAs were characterized using Raman spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM).


2004 ◽  
Vol 836 ◽  
Author(s):  
S. L. Wang ◽  
S. H. Lee ◽  
A. Gupta ◽  
A. D. Compaan

ABSTRACTCd1-xMnxTe alloy films with band gaps of 1.6 ∼ 1.8 eV have been deposited by RF magnetron sputtering for solar-cell applications. The films have been treated by chloride vapors to improve the photovoltaic performance. These as-deposited and chloride-treated CdMnTe films have been investigated by Raman spectroscopy, x-ray diffraction (XRD) and scanning electron microscopy (SEM). Raman results indicate that Te and/or TeO2 exists in the annealed samples depending on anneal conditions.


2012 ◽  
Vol 27 (2) ◽  
pp. 131-136
Author(s):  
Bozidar Cekic ◽  
Valentin Ivanovski ◽  
Aleksandar Djordjevic ◽  
Velimir Aleksic ◽  
Zorica Tomic ◽  
...  

The paper addresses the issue of health risk associated with the presence of chrysotile in the soil type ranker formed on massive serpentines occurring in the area of Bubanj Potok, a settlement located in the southern Belgrade environs, Serbia. Characterization of the ranker soil was conducted by scanning electron microscopy, X-ray diffraction, micro-Raman spectroscopy and transmission 57Fe M?ssbauer spectroscopy. Scanning electron microscopy figures showed regular shaped smectite (montmorillonite) particles, aggregates of chlorite, and elongated sheets of serpentines minerals antigorite. X-ray diffraction analysis confirmed the presence of detrital mineral quartz polymorph as well as minor amounts of other mineral species. Micro-Raman spectroscopy identified the presence of dominant minerals, such as montmorillonite, kaolinite, muscovite, gypsum, calcite, albite, amphiboles (hornblende/kaersutite) and orthoclase. Important polymorph silica modifications of quartz, olivine (forsterite), pyroxene (enstatite/ferrosilite, diopside/hedenbergite), and serpentine (antigorite/lizardite/chrysotile) were identified.


Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7585
Author(s):  
Maya Musa ◽  
Riccardo Rossini ◽  
Daniela Di Martino ◽  
Maria Pia Riccardi ◽  
Massimiliano Clemenza ◽  
...  

Meteorite characterisation represents a privileged and unique opportunity to increase our knowledge about the materials composing the Universe and, particularly, the Proto Solar System. Moreover, meteorites studies evolve contextually with the development of analytical technologies. In the present paper, the results from an unclassified stony meteorite (chondrite) characterisation have been reported on the basis of the innovative analytical protocol presented here. Advanced Mapping by micro-Raman Spectroscopy and Scanning Electron Microscopy equipped with Energy Dispersive Spectroscopy have been combined to disclose molecular and elemental features on the same regions sample at a micrometric resolution. Thanks to their non-destructive properties, the mapping tools of both instruments have been applied to single chondrules analysis and the best match between the mineralogical information and the chemical composition has been obtained. This combined approach proved to be highly suitable in disclosing the crystallinity features of the phases, with in-depth spatial and morphological details too.


2016 ◽  
Vol 16 (4) ◽  
pp. 3617-3621 ◽  
Author(s):  
Yuping Wang ◽  
Mingxia Li ◽  
Kai Pan ◽  
Rong Li ◽  
Naiying Fan ◽  
...  

Rhombic NaLa(MoO4)2:Ln3+ (Ln = Eu and Tb) nanocrystals were synthesized by a hydrothermal method. The structures and morphologies of the nanocrystals were characterized by X-ray diffraction, Raman spectroscopy, and scanning electron microscopy. The results indicated that the crystalline size increased with increasing Na2MoO4 content. The photoluminescence properties of NaLa(MoO4)2:Ln3+ nanocrystals were investigated in detail. In the emission spectra of NaLa(MoO4)2:Eu3+ nanocrystals, the 5D0 → 7F2 is dominant, and the peak positions and spectral shapes of emissions were independent of Eu3+ concentration. The luminescence intensity increased with increasing Eu3+ concentration, up to about 10 mol%, and then decreased. In the emission spectra of NaLa(MoO4)2:Tb3+ nanocrystals, the 5D4 → 7F5 is dominant. The sample with a dopant concentration of 20 mol% showed the highest emission intensity.


2002 ◽  
Vol 16 (14) ◽  
pp. 525-537
Author(s):  
SAADAT. A. SIDDIQI ◽  
NASIR A. KHAN ◽  
M. SABIEH ANWAR

Impedance spectroscopy (IS) is a non-destructive technique used for obtaining valuable information about bulk conductivities, dielectric constants, phase composition and grain boundaries of important ceramic materials, amongst many others. We obtained Nyquist plots for four different hot-pressed Si 3 N 4 samples in two different frequency regimes: 1 Hz to 30 MHz and 1 kHz to 100 kHz. The information obtained was compared against results from scanning electron microscopy (SEM) and X-ray diffraction (XRD). The limitations of the frequency response techniques are also discussed.


Zoosymposia ◽  
2016 ◽  
Vol 11 ◽  
pp. 101-120 ◽  
Author(s):  
JAVIER ALBA-TERCEDOR

Here I present the results obtained by scanning male adults of two mayfly (Ephemeroptera) species with a high resolution micro-tomographic scanner, allowing observation of external structures, with similar results to those obtained under scanning electron microscopy. Moreover, this non-destructive technique permits investigation of the internal structures, and to “navigate” inside them, in a way never before imagined. Moreover by using different transfer functions and in accordance with the X-ray transparency, it is possible to assign different colours to highlight different anatomical parts, and to obtain “aesthetic” images. Results are compared and discussed with previous findings. It is postulated that differences in the diameter sizes of the ommatidia, when comparing dorso-frontal and ventro-lateral parts of the compounds eyes, represent an evolutionary advantage enabling increased accuracy in movement displacement detection of competing males within the swarm.


Minerals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1063
Author(s):  
Ariadne Kostomitsopoulou Marketou ◽  
Fabrizio Andriulo ◽  
Calin Steindal ◽  
Søren Handberg

This paper aims to expand our understanding of the processes involved in the production of the artificial pigment Egyptian blue through the scientific examination of pigments found in the first century BCE workshop of the Greek island of Kos. There, 136 Egyptian blue pellets were brought to light, including successfully produced pellets, as well as partially successful and unsuccessful products. This study is based on the examination of eighteen samples obtained from pellets of various textures and tones of blue, including light and dark blue pigments, coarse and fine-grained materials, and one unsuccessful pellet of dark green/grey colour. The samples were examined by optical microscopy, scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS), and micro-Raman spectroscopy. These complementary microanalytical techniques provide localised information about the chemical and mineralogical composition of this multicomponent material, at a single-grain level. The results shed light on the firing procedure and indicate possible sources for raw materials (beach sand, copper alloys), as well as demonstrating the use of a low-alkali starting mixture. Moreover, two different process for the production of light blue pigments were identified: (a) decreased firing time and (b) grinding of the initially produced pellet and mixing with cobalt-containing material.


2014 ◽  
Vol 602-603 ◽  
pp. 463-466 ◽  
Author(s):  
Jin Jia ◽  
Yuan Yuan Zhu ◽  
Ya Fei Zhang ◽  
Ruo Yu Chen ◽  
Bao Lin Xing ◽  
...  

Carbide-derived carbons (CDCs) are produced from carbides by removing non-carbon elements in the process of selective etching. In this paper, CDC was prepared from TiC by chlorination at the temperature range of 600~1100°C. In the chlorinating process, carbide-derived carbon with different microstructure was obtained by controlling the reaction temperature. The structures of CDC were revealed with X-ray diffraction and Raman spectroscopy. The morphologies of CDC were analyzed by scanning electron microscope. From X-ray diffraction analysis, the CDC obtained from TiC in this experiment mainly consisted of amorphous carbon. Basing on scanning electron microscopy, carbide-derived carbon from TiC maintained the shape and size of TiC particles. Keywords: Carbide-derived carbons; chlorination; TiC


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