scholarly journals Contribution of X-Ray Diffraction in the Identification of Crystalline Phases of the Mineralization Hosted in the Mesozoic Cover of the Tazzeka Hercynian Massif – Maghrawa Region - Morocco

2020 ◽  
Vol 8 (3) ◽  
pp. 54-67
Author(s):  
Naoufal Saoud ◽  
Issam Derkaoui ◽  
Jaouad Choukrad ◽  
Mohamed Amine El Moussalim ◽  
Mohamed Charroud
Keyword(s):  
X Ray Diffraction ◽  
Crystalline Phases ◽  
X Ray

Thermal stability and miscibility of co-evaporated methyl ammonium lead halide (MAPbX3, X = I, Br, Cl) thin films analysed by in situ X-ray diffraction

2018 ◽  
Vol 6 (24) ◽  
pp. 11496-11506 ◽  
Author(s):  
Paul Pistor ◽  
Thomas Burwig ◽  
Carlo Brzuska ◽  
Björn Weber ◽  
Wolfgang Fränzel
Keyword(s):  
Thin Films ◽  
Thermal Stability ◽  
Thermal Treatment ◽  
Phase Evolution ◽  
X Ray Diffraction ◽  
Crystalline Phases ◽  
X Ray ◽  
Subsequent Thermal Treatment ◽  
Lead Halide

We present the identification of crystalline phases by in situ X-ray diffraction during growth and monitor the phase evolution during subsequent thermal treatment of CH3NH3PbX3 (X = I, Br, Cl) perovskite thin films.

Structure Characterization of Sintered CaO-Al2O3-SiO2 Glass-Ceramic Reinforced with Spodumene

2013 ◽  
Vol 834-836 ◽  
pp. 309-314
Author(s):  
Zi Fan Xiao ◽  
Jin Shu Cheng ◽  
Jun Xie
Keyword(s):  
Glass Ceramic ◽  
Energy Dispersive Spectrometry ◽  
Crystal Size ◽  
Bending Strength ◽  
Glass Ceramics ◽  
Structure Characterization ◽  
X Ray Diffraction ◽  
Crystalline Phases ◽  
X Ray

A glass-ceramic belonging to the CaO-Al2O3-SiO2(CAS) system with different composition of spodumene and doping the Li2O with amount between 0~2.5 % (mass fraction) were prepared by onestage heat treatment, under sintering and crystallization temperature at 1120 °C for two hours. In this paper, differential thermal analysis, X-ray diffraction, scanning electron microscopy, energy dispersive spectrometry and bending strength test were employed to investigate the microstructure and properties of all samples. β-wollastonite crystals were identified as the major crystalline phases, and increasing Li2O was found to be benefit for the crystallization and tiny crystalline phases remelting, resulting in the content of major crystalline phases increased first and then decreased with increasing the expense of spodumene. Meanwhile, the crystal size can be positively related with the content of Li2O. The preferable admixed dosage of spodumene can be obtained, besides the strength of glass-ceramics can be more than 90 MPa.

Synthesis and Ionic Conductivity of MAlSi3O8 (M = Li, Na, K)

2018 ◽  
Vol 790 ◽  
pp. 9-14
Author(s):  
Shin Ichi Furusawa ◽  
Yohei Minami
Keyword(s):  
Activation Energy ◽  
Ionic Conductivity ◽  
Ionic Radius ◽  
Ionic Conduction ◽  
Solid Phase ◽  
Solid Phase Reaction ◽  
Phase Reaction ◽  
X Ray Diffraction ◽  
Crystalline Phases ◽  
X Ray

MAlSi3O8 (M = Li, Na, K) was synthesized by solid-phase reaction at 1000 °C using M2CO3 (M = Li, Na, K), Al2O3, and SiO2 as the starting materials, and its ionic conduction was studied in the temperature range 475–800 K. It was confirmed from powder X-ray diffraction profiles that the crystalline phases of the prepared MAlSi3O8 were the same as those of orthoclase. Moreover, the ionic conductivity of NaAlSi3O8 was about 10 times higher than that of LiAlSi3O8 and KAlSi3O8. The activation energies for ionic conduction were estimated to be in the range of 0.70–0.77 eV, with NaAlSi3O8 exhibiting the lowest activation energy. The result suggests that the magnitude of the activation energy cannot be determined only from the ionic radius.

X-Ray Diffraction of Iron Containing Samples: The Importance of a Suitable Configuration

2017 ◽  
Vol 262 ◽  
pp. 545-548 ◽  
Author(s):  
Yvonne M. Mos ◽  
Arnold C. Vermeulen ◽  
Cees N.J. Buisman ◽  
Jan Weijma
Keyword(s):  
Radiation Source ◽  
The Other ◽  
Phase Identification ◽  
X Ray Diffraction ◽  
High Quality ◽  
Crystalline Phases ◽  
X Ray ◽  
Other Hand ◽  
Cobalt Radiation

X-ray diffraction (XRD) is a commonly used technology to identify crystalline phases. However, care must be taken with the combination of XRD configuration and sample. Copper (most commonly used radiation source) is a poor match with iron containing materials due to induced fluorescence. Magnetite and maghemite are analysed in different configurations using copper or cobalt radiation. Results show the effects of fluorescence repressing measures and the superiority of diffractograms obtained with cobalt radiation. Diffractograms obtained with copper radiation make incontestable phase identification often impossible. Cobalt radiation on the other hand yields high quality diffractograms, making phase identification straightforward.

Crystallization of a SiO2-MgO-Al2O3-K2O-Fe2O3-F Glass

2007 ◽  
Vol 336-338 ◽  
pp. 1829-1832 ◽  
Author(s):  
Qing Bo Tian ◽  
Yue Wang ◽  
Xue Tao Yue ◽  
Yan Sheng Yin ◽  
Su Hua Fan
Keyword(s):  
Phase Separation ◽  
Electron Probe ◽  
X Ray Diffraction ◽  
Crystalline Phases ◽  
Present Glass ◽  
X Ray ◽  
Heat Treated ◽  
Mica Crystal ◽  
Step Heat Treatment ◽  
Scanning Electron

The phase-separation and the crystallization of SiO2-MgO-Al2O3-K2O-Fe2O3-F glass were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electron probe of microanalyzers (EPMA). The results reveal that the varieties and the morphology of crystalline phases formed depend sensitively on the thermal treatment schedules. During the isothermal treatments, the crystalline phases of mica, mica and iron oxide (FeFeO4), and FeFeO4 as major crystals are precipitated in the glass samples heat-treated at 900, 1000 and 1050°C respectively. However, the two-step heat treatment beginning at 900°C for 1h and subsequently followed at 1050°C for 1h leads to the precipitation of mica crystal and no any signs of FeFeO4 crystalline phase is observed. Also the morphology of sample is different from that of the isothermally treated glass at 1050°C, but is similar from that of sample at 900°C. A “worm”-shaped phase-separation is observed in the sample heated at 800°C for 0.5h, which exhibits different morphology from that of droplet- or globule-shape conventionally discerned. EPMA results show that the incorporation of Fe2O3 accelerates accumulation of fluorine element, promoting the phase-separation and the crystallization of the present glass.

scholarly journals Crystallization and Quantification of Crystalline and Non-Crystalline Phases in Kaolin-Based Cordierites

Materials ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3104 ◽  
Author(s):  
Marta Valášková ◽  
Zdeněk Klika ◽  
Boris Novosad ◽  
Bedřich Smetana
Keyword(s):  
Raw Material ◽  
X Ray Diffraction ◽  
Crystalline Phases ◽  
X Ray ◽  
Mineral Phases ◽  
Chemical Variability ◽  
Bulk Chemical ◽  
Size Variability ◽  
Cordierite Ceramics ◽  
Cordierite Structure

Kaolin is most often used as traditional raw material in ceramic industry. The purpose of the study was to obtain understanding of the structural and chemical variability of cordierite ceramics influenced by chemical and mineralogical properties of six raw kaolins taken from different localities when they are applied in ceramics mixtures with vermiculite and sintered up to 1300 °C. The X-ray diffraction and simultaneous thermogravimetric and differential thermal analysis were used to identify and characterize crystalline mineral phases and the course of reactions during the heating. The percentages of the crystalline and non-crystalline phases were newly determined by recalculation of the bulk chemical analyses of kaolins and cordierite ceramics using Chemical Quantitative Mineral Analysis (CQMA) method. Varying amounts of minerals in kaolins: kaolinite from 73.3 to 85.0, muscovite from 4.2 to 9.9, and quartz from 6.0 to 19.5 (mass %) affected amount of cordierite/indialite from 75.2 to 85.1, enstatite from 5.8 to 8.9 (when are calculated as their maximal possible percentages), and non-crystalline phases from 8.8 to 15.1 (mass %) in cordierite ceramics. Regression analysis predicted high relationship between quantity of: (a) kaolinite in kaolins and crystalline cordierite and (b) quartz in kaolins and non-crystalline phases in the ceramics. The migration of potassium from muscovite into the cordierite structure, melting point and crystallization of cordierite/indialite phases and pore size variability in relation to impurity of kaolins are documented and discussed.

scholarly journals Influence of Different Heat Treatment Temperatures on the Microstructure, Corrosion, and Mechanical Properties Behavior of Fe-Based Amorphous/Nanocrystalline Coatings

Coatings ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 858
Author(s):  
Shenglin Liu ◽  
Yongsheng Zhu ◽  
Xinyue Lai ◽  
Xueping Zheng ◽  
Runnan Jia ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Heat Treatment Temperature ◽  
Annealing Treatment ◽  
Treatment Temperature ◽  
X Ray Diffraction ◽  
Crystalline Phases ◽  
X Ray ◽  
Different Temperatures ◽  
Sprayed Coating

Fe-based amorphous/nanocrystalline coatings with smooth, compact interior structure and low porosity were fabricated via supersonic plasma spraying (SPS). The coatings showed outstanding corrosion resistance in a 3.5% NaCl solution at room temperature. In order to analyze the effect of annealing treatment on the microstructure, corrosion resistance and microhardness, the as-sprayed coating was annealed for 1 h under different temperatures such as 350, 450, 550 and 650 °C, respectively. The results showed that the number of oxides and cracks in the coatings presented an obvious increase with increasing annealing temperature, and the corrosion resistance of the coatings showed an obvious reduction. However, the microhardness of coatings showed an important increase. The microhardness of the coating could reach 1018 HV when the heat treatment temperature reached 650 °C. The X-ray diffraction (XRD) results showed that there appeared a number of crystalline phases in the coating when the heat treatment temperature was at 650 °C. The crystalline phases led to the increase of the microhardness.

Effects of Spraying Parameters on Phase Formation and Distribution in Plasma-Sprayed Hydroxyapatite Coatings

2000 ◽  
Author(s):  
L. Sun ◽  
C.C. Berndt ◽  
R.S. Lima ◽  
A. Kucuk ◽  
K.A. Khor
Keyword(s):  
Opposite Effect ◽  
X Ray Diffraction ◽  
Crystalline Phases ◽  
Tetracalcium Phosphate ◽  
X Ray ◽  
Impurity Phases ◽  
Hydroxyapatite Coatings ◽  
Spraying Parameters ◽  
Plasma Sprayed ◽  
Spray Dried

Abstract Calcined spray-dried hydroxyapatite (Ca10(PO4)(OH)6; i.e., HA) powders were atmospherically plasma sprayed (APS) using various process parameters. The resulting phases within the coating surface and the interface between the coating and the substrate were analyzed using X-ray diffraction (XRD) methods. This XRD revealed the presence of both amorphous (i.e., amorphous calcium phosphate: ACP) and crystalline phases. The crystalline phases included both HA and some impurity phases from the decomposition of HA, such as tricalcium phosphate (α-TCP and β-TCP), tetracalcium phosphate (TTCP) and calcium oxide (CaO). The crystallinity of HA decreased with increasing spray power and stand-off distance (SOD). The percentage of all impurity phases increased with the spray power. The percentage of both TCP and TTCP decreased with the SOD while the CaO percentage increased. In addition, the percentage of ACP and CaO were higher in the interface than at the surface of the coating while the percentage of TCP and TTCP exhibited the opposite effect.

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