Complex colour and chemical zoning of sodalite-group phases in a haüynophyre lava from Mt. Vulture, Italy

2004 ◽  
Vol 68 (4) ◽  
pp. 591-614 ◽  
Author(s):  
A. Di Muro ◽  
E. Bonaccorsi ◽  
C. Principe

AbstractThe haüynophyre emitted from a parasitic vent of the Vulture stratovolcano is a S- and Cl-rich, leucitemelilite- bearing lava flow containing an unusually large amount of sodalite-group minerals (>23 vol.%). Mineralogical and chemical study of phenocrysts has led to the identification of black haüynes, blue lazurites and of Cl-rich white or black noseans. X-ray diffraction (XRD) study confirms the occurrence of nosean having a low symmetry (P23). Raman spectra and XRD data show that S is fully oxidized to SO4 in black haüynes and in white noseans, while it is partly reduced to form S3– groups in blue lazurites, which also contain H2O molecules. Structural and chemical data strongly question the validity of the Hogarth and Griffin (1976) method widely used to resolve the ratio S6+/S2– in sodalite-group phases from EMPA data. Among euhedral phenocrysts, large lazurites are only faintly zoned. All other phases show variable core-rim chemical zoning and many phenocrysts are partially resorbed and/or colour-zoned. Black haüynes have highly variable S/Cl and slightly lower SiO2/Al2O3 ratios, larger FeTOT contents and more compatible trace elements than lazurites. Thin opaque noseansodalite rims surrounding all crystals are interpreted as a result of rapid crystallization driven by exsolution of a S-scavenging fluid phase. We suggest that the extreme complexity of the mineralogical assemblage reflects variable aSiO2 and aH2O of the silicate melts.

2003 ◽  
Vol 52 (10) ◽  
pp. 2095-2099 ◽  
Author(s):  
A. A. Korlyukov ◽  
A. M. Starosotnikov ◽  
K. A. Lyssenko ◽  
S. A. Shevelev ◽  
M. Yu. Antipin

Author(s):  
H. B. Gasimov ◽  
R. M. Rzayev

Cu2Te single crystal was grown by the Bridgman method. X-ray diffraction (XRD) study of Cu2Te single crystals in the temperature range of 293–893 K was performed and possible phase transitions in the mentioned range of temperature have been investigated. (Cu2Te)[Formula: see text](ZnTe)[Formula: see text] single crystals also were grown with [Formula: see text], 0.05, 0.10 concentrations and structural properties of the obtained single crystals were investigated by the XRD method in the temperature range 293–893 K. Lattice parameters and possible phase transitions in the mention temperature range were determined for (Cu2Te)[Formula: see text](ZnTe)[Formula: see text] single crystals for [Formula: see text], 0.05, 0.10 concentrations.


2000 ◽  
Vol 33 (6) ◽  
pp. 1351-1359 ◽  
Author(s):  
A. Ben Haj Amara ◽  
H. Ben Rhaiem ◽  
A. Plançon

Nacrite has been intercalated with two polar organic molecules: dimethyl sulfoxide (DMSO) andN-methylacetamide (NMA). The homogeneous nacrite complexes have been studied by X-ray diffraction (XRD) and infrared (IR) spectroscopy. The XRD study is based on a comparison between experimental and calculated patterns. The structures of the intercalated compounds have been determined, including the mutual positions of the layers after intercalation and the positions of the intercalated molecules in the interlayer space. It has been shown that the intercalation process causes not only a swelling of the interlayer space but also a shift in the mutual in-plane positions of the layers. This shift depends on the nature of the intercalated molecules and is related to their shape and the hydrogen bonds which are established with the surrounding surfaces. For a given molecule, the intercalation process is the same for the different polytypes of the kaolinite family. These XRD results are consistent with those of IR spectroscopy.


2021 ◽  
Vol 9 (8) ◽  
pp. 1637-1641
Author(s):  
Abhishek Abhishek

Introduction: Mrityunjaya Rasa is a Herbo-Mineral formulation, mentioned in Jwara Chikitsa along with various Anupana like Madhu, Aardraka Swarasa, and Jeeraka Kashaya with Guda. Ingredients like Shudha Hingula, Shudha Gandhaka, Shudha Vatsanabha, Shudha Tankana, Pippali and Maricha with properties of Tikta, Katu Rasa Teekshna Guna and Deepana-Pachana, Swedajanana, Yogavahi and Jwaraghna action show the significant result on various types of fever. To attain desired qualities in the finished product, it is much needed to check efficacy on modern parameters for standardization purposes. Thus, Mrityunjaya Rasa was subjected to X- ray diffraction spectroscopy to ensure SOPs followed for preparation. Aim: The study aimed to analyse the results of X-ray diffraction spectroscopy of Mrityunjaya Rasa. Materials and Methods: X-ray diffraction spectroscopy of Mrityunjaya Rasa was carried out at MIT–central instrumentation facility – innovation centre, Manipal, Udupi. Results: XRD study indicates that Mrityunjaya Rasa contains HgS (cinnabar), mercury sulphide in major phase and borax and elements Na, Ca, Mn, Mg, K, P, Zn, C, Cl2, Fe and B in minor phase. Conclusions: Mrityunjaya Rasa contains HgS (cinnabar), mercury sulphide in major phase and borax and other elements like Na, Ca, Mn, Mg, K, P, Zn, C, Cl2, Fe, and B are also present. Compounds and elements are present due to ingredients and Shodhana media which were used. This study can be a path for establishing the thumbprint of SOP for Mrityunjaya Rasa, a herbomineral compound formulation. Keywords: Mrityunjaya Rasa, XRD, HgS, S, Borax, Na, Ca, Mn etc.


Chemija ◽  
2020 ◽  
Vol 31 (3) ◽  
Author(s):  
Ehab AlShamaileh ◽  
Muayad Esaifan ◽  
Qusay Abu-Afifeh

The formation of metal oxide-based hydroxysodalite by alkali-activation of kaolinite is studied using X-ray diffraction (XRD) study and differential scanning calorimetry (DSC) analysis. Different metal oxides (CoO, MgO, FeO and SiO2) were used to form the metal oxide-based hydroxysodalite. The transformation from kaolinite into hydroxysodalite is confirmed by XRD. In the thermodynamic study, the maximum peak temperatures for DSC curves at various heating rates were used to determine the activation energy (Ea) of the hydroxysodalite formation. With magnesium oxide and cobalt oxide, the formation process was found to be exothermic while it was endothermic with iron oxide.


2005 ◽  
Vol 60 (5) ◽  
pp. 548-554 ◽  
Author(s):  
Hortensia Parra-Delgado ◽  
Rubén A. Toscano ◽  
Aída N. García-Argaez ◽  
Mariano Martínez-Vázquez

The known nor-diterpene (16R)-ent-17-hydroxy-19-nor-kaur-4-en-3-one and the new norditerpene (16R)-ent-19-nor-kaur-4-en-3-oxo-17-oic acid were obtained as a crystalline mixture from roots of C. ghiesbregthiana. Their structures were deduced by spectroscopic means and confirmed by a X-ray diffraction study of the crystalline mixture. Additionally, ursolic and betulinic acids, skimmin, and sucrose were isolated. This is the first chemical study of a member of the Coutaportla genus.


2019 ◽  
Vol 28 (1) ◽  
pp. 153-161 ◽  
Author(s):  
Subhasish Sarkar ◽  
Arghya Mukherjee ◽  
Rishav Kumar Baranwal ◽  
Jhumpa De ◽  
Chanchal Biswas ◽  
...  

AbstractThe current study focuses on the parametric optimization of electroless Ni-Co-P coating considering surface roughness as a response using Box-Behnken Design (BBD) of experiment. The two bath parameters namely the concentration of cobalt sulphate and sodium hypophosphite were varied along with the bath temperature to predict the variation in surface roughness. Analysis of variance (ANOVA) method has been applied to determine the interactions of the substantial factors which dominate the surface roughness of the coating. The process parameters for surface roughness of the coating were optimized by successfully utilizing the statistical model of Box-Behnken Design (BBD) of experiment. From the BBD model, the optimum condition for the deposition of the coating has been evaluated. In that specific condition, the surface roughness of the as-deposited coating is found to be 0.913μm. Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), and X-Ray Diffraction (XRD) study have been utilized to characterize the electroless Ni-Co-P coating deposited in optimized condition.


2014 ◽  
Vol 670-671 ◽  
pp. 26-29
Author(s):  
Zhi Long Pan ◽  
Shi Liang Ao ◽  
Jian Ping Jia

Oxide free Tin nanoparticles were synthesized from a chemical reduction method. Their morphological and thermal characterizations were studied in this paper. The X-ray diffraction (XRD) study showed that no oxides of Tin nanoparticles were formed. The thermal characterization by differential scanning calorimetry (DSC) exhibited the size dependency of the melting points. The melting point was as low as 202.16°C.


2017 ◽  
Vol 81 (2) ◽  
pp. 339-354 ◽  
Author(s):  
E. Schingaro ◽  
E. Mesto ◽  
M. Lacalamita ◽  
F. Scordari ◽  
E. Kaneva ◽  
...  

AbstractA crystal chemical study of narsarsukite from the Murun alkaline massif, Russia has been carried out combining single-crystal X-ray diffraction, electron microprobe analyses, micro-Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). The narsarsukite single crystals are tetragonal (space group I4/m) with unit-cell parameters: 10.7140(1) ≤ a ≤ 10.7183(2) Å and 7.9478(1) ≤ c ≤ 7.9511(1) Å. The XPS analysis showed that Fe occurs in the mineral as Fe3+, whereas the FTIR spectrum showed that the sample studied is anhydrous. The average crystal chemical formula of the Murun narsarsukite is: Na2.04K0.01(V0.015+Ti0.74Zr0.01Al0.01Fe0.223+Mg0.01)1.00Si4.00(O10.74F0.23OH0.03)11.00. Structural disorder at octahedral and interstitial sites was modelled and also discussed in consideration of the main substitutional mechanism Ti4+ + O2– ↔ Fe3+ + (F–, OH–) active in the structure of the mineral.


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