Petrography And Field Study Of Andesitic Ignimbrite In Temangan, Kelantan

The volcanic rocks in Temangan, Kelantan consist of felsic to intermediate volcanic rocks, that is mainly of pyroclastic with rhyolitic, dacitic, and andesitic tuff. A geological review has been carried out in Kampung Bukit Besi, Temangan, in Kelantan, Malaysia, which is composed of schist, shale, andesite, and ignimbrite. In Temangan, andesite and ignimbrite show an intimate relationship, as the ignimbrite exists as the fragments and andesite as the matrix. The methodology used in this study are petrography and X-ray Diffraction (XRD) analyses, to determine the mineralogical composition of andesitic ignimbrite. Andesite shows aphenitic and porphyritic textures and consist of pyroxene, plagioclase, alkali feldspar, quartz, biotite and iron oxides. A range of plagioclase textures indicate imperfect equilibrium condition from andesite, reflecting plagioclase dissolution and regrowth. The structural analysis suggest that thrust fault occurred in the study area. Andesite and ignimbrite of the two stages are suggested to have derived from the andesite magma eruption which produced pyroclastic flow eruptions in small amount in most caldera volcanoes at high temperature gradient.

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Sedimentary Clays as Geopolymer Precursor

International Journal of Engineering Research in Africa ◽

10.4028/www.scientific.net/jera.39.97 ◽

2018 ◽

Vol 39 ◽

pp. 97-111

Author(s):

F. Mostefa ◽

Nasr Eddine Bouhamou ◽

H.A. Mesbah ◽

Salima Aggoun ◽

D. Mekhatria

Keyword(s):

Sodium Hydroxide ◽

Mineralogical Composition ◽

Cementitious Materials ◽

Raw Material ◽

X Ray Diffraction ◽

Calcination Time ◽

Calorimetric Analysis ◽

X Ray ◽

Before And After ◽

Mechanical Performances

This work aims to study the feasibility of making a geopolymer cement based on dredged sediments, from the Fergoug dam (Algeria) and to evaluate their construction potential particularly interesting in the field of special cementitious materials. These sediments due to their mineralogical composition as aluminosilicates; are materials that can be used after heat treatment. Sedimentary clays were characterized before and after calcination by X-ray diffraction, ATG / ATD, spectroscopy (FTIR) and XRF analysis. The calcination was carried out on the raw material sieved at 80 μm for a temperature of 750 ° C, for 3.4 and 5 hours. The reactivity of the calcined products was measured using isothermal calorimetric analysis (DSC) on pastes prepared by mixing an alkaline solution of sodium hydroxide (NaOH) 8 M in an amount allowing to have a Na / Al ratio close to 1 (1: 1). Also, cubic mortar samples were prepared with a ratio L / S: 0.8, sealed and cured for 24 hours at 60 ° C and then at room temperature until the day they were submited to mechanical testing. to check the extent of geopolymerization. The results obtained allowed to optimize the calcination time of 5 hours for a better reactivity of these sediments, and a concentration of 8M of sodium hydroxide and more suitable to have the best mechanical performances.

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Plastic deformations in kyanites by tectonometamorphic processes: a single-crystal X-ray diffraction study

Mineralogical Magazine ◽

10.1180/minmag.2009.073.3.359 ◽

2009 ◽

Vol 73 (3) ◽

pp. 359-371 ◽

Cited By ~ 5

Author(s):

G. D. Gatta ◽

N. Rotiroti ◽

M. Zucali

Keyword(s):

Single Crystal ◽

X Ray Diffraction ◽

Plastic Deformations ◽

X Ray ◽

Deformational History ◽

Significant Difference ◽

Elliptical Section ◽

History Of ◽

Diffraction Patterns ◽

Two Stages

AbstractThe crystalch emistry and crystal structure of naturalky anite crystals from the Eclogitic Micaschists Complex of the Sesia-Lanzo Zone, Western Italian Alps, have been investigated by means of optical microscopy, wavelength dispersive X-ray microanalysis, and single-crystal X-ray diffraction. The association of kyanite + garnet + phengitic-mica + chloritoid suggests that the eclogite-facies stages occurred at P ≤ 2.1 GPa and T ≤ 650ºC. Kyanite grains are large (cm-sized) porphyroblasts grown dynamically during one of the deformational events related to the subduction of the Austroalpine continentalcr ust. Under the polarizing microscope, kyanite grains show almost homogeneous cores, whereas rims are sometimes symplectitic aggregates of quartz and kyanite, confirming at least two stages of growth most likely related to the multistage deformational history of these rocks. Chemical analysis shows that Fe3+ is the major substituting cation for Al3+, ranging between 0.038 and 0.067 a.p.f.u.The single-crystal X-ray diffraction investigation of the kyanites shows severely textured patterns on the (h0l)*-plane. Such evidence is not observed in the unwarped diffraction patterns on (0kl)* and (hk0)*. The most significant difference between the structuralp arameters refined in this study, with respect to those of previously published unstrained gem-quality crystals, concerns the displacement parameters. The anisotropic displacement ellipsoids of all the atomic sites are significantly larger than those previously described, and systematically oriented with the largest elliptical section almost perpendicular to [010]. The larger ellipsoids in the kyanite crystal investigated here reflect the displacement of the centre of gravity of the electron distribution, rather than an anomalous atomic thermal motion. The magnitude and orientation of the displacement parameters and the textured/strained diffraction pattern may be the result of two combined effects: (1) that the kyanite crystals are actually composed of several blocks; (2) the crystals are affected by a pervasive residual strain, as a result of tectonometamorphic plastic deformations and re-crystallization.

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Growth mechanism and characterization of ZnO nano-tubes synthesized using the hydrothermal-etching method

Chemical Papers ◽

10.2478/s11696-009-0082-y ◽

2009 ◽

Vol 63 (6) ◽

Cited By ~ 10

Author(s):

Yan Li ◽

Chuan-Sheng Liu ◽

Yun-Ling Zou

Keyword(s):

Room Temperature ◽

Morphological Analysis ◽

Diffraction Field ◽

X Ray Diffraction ◽

X Ray ◽

Room Temperature Photoluminescence ◽

Etching Method ◽

Nano Rods ◽

Two Stages

AbstractZnO nano-tubes (ZNTs) have been successfully synthesized via a simple hydrothermal-etching method, and characterized by X-ray diffraction, field emission scanning electron microscopy and room temperature photoluminescence measurement. The as-synthesized ZNTs have a diameter of 500 nm, wall thickness of 20–30 nm, and length of 5 µm. Intensity of the plane (0002) diffraction peak, compared with that of plane (10$$ \bar 1 $$0) of ZNTs, is obviously lower than that of ZnO nano-rods. This phenomenon can be caused by the smaller cross section of plane (0002) of the nano-tubes compared with that of other morphologies. On basis of the morphological analysis, the formation process of nano-tubes can be proposed in two stages: hydrothermal growth and reaction etching process.

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Assessment of Laser Effects on the Structure and Electrical Properties of the Compound Bi2-xAgxSr2Ca2Cu3O10+δ Superconducting

NeuroQuantology ◽

10.14704/nq.2021.19.11.nq21181 ◽

2021 ◽

Vol 19 (11) ◽

pp. 108-115

Author(s):

Nihad Ali Shafeek

Keyword(s):

Critical Temperature ◽

Hydraulic Press ◽

Electrical Characteristics ◽

X Ray Diffraction ◽

Solid State Method ◽

X Ray ◽

Compensation Ratio ◽

Superconducting Compound ◽

State Method ◽

Two Stages

This research contains preparing the superconducting compound Bi2-xAgxSr2Ca2Cu3O10+δ and studying its structural and electrical characteristics. The samples were prepared using the solid-state method in two stages, and different concentrations of x were (x= 0.2,0.4,0.6,0.8) replaced instead of bismuth Bi. Then, using a hydraulic press 9 ton/cm2 and sintering with a temperature of 850°C, the samples were pressed. Next, x-ray diffraction is used to study the structural properties. The study of these samples was presented in different proportions of x values, where x = 0.4 is the best compensation ratio of x. A critical temperature of 1400C and the Tetragonal structure was got. After that, the effect of laser nidinium _ yak (Nd: YAG laser) was used on the compositional. It was found that the temperature value increased, so we got the best critical temperature, which is 142 0C.

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Crystallization of simonkolleite (Zn5Cl2(OH)8 ∙ H2O) in powder samples prepared for mineral composition analysis by quantitative X-ray diffraction (QXRD)

Nafta-Gaz ◽

10.18668/ng.2021.05.02 ◽

2021 ◽

Vol 77 (5) ◽

pp. 293-298

Author(s):

Urszula Zagórska ◽

◽

Sylwia Kowalska ◽

Keyword(s):

Quantitative Analysis ◽

Internal Standard ◽

Mineralogical Composition ◽

Hydrocarbon Exploration ◽

Composition Analysis ◽

Internal Standard Method ◽

X Ray Diffraction ◽

Method Error ◽

X Ray ◽

Significant Difference

The analysis of mineralogical composition by quantitative X-ray diffraction (QXRD) is one of the standard research methods used in hydrocarbon exploration. In order to improve it and to obtain better results, the methodology of quantitative analysis used at Well Logging Department is being periodically (more or less) modified. After the introduction of the improvements, comparative analyses were performed on archival samples. Reflections from an unidentified phase which did not occur in the tested Rotliegend sandstone samples were noticed on X-ray diffractograms of archival samples. Reflections of a mineral called simonkolleite were identified in the X-ray diffraction database. Chemically it is a hydrated zinc chloride of the formula: Zn5Cl2(OH)8 × H2O. Analysis of the composition of samples in which simonkolleite crystallised, indicated that the mineral is being formed in the result of the slow reaction of zinc oxide with halite (NaCl) and water vapour. An attempt was made to determine the influence of the presence of this mineral on the results of the quantitative analysis of mineralogical composition. The above methodology was applied on a group of ten samples. The results of the quantitative analysis conducted for archival samples stored with added zincite standard containing simonkolleite and for new, freshly grinded (without artifact) samples were compared. The comparison of the obtained results showed a slight influence of this mineral on the quantitative composition of the remaining components. The difference between the results usually did not exceed the method error. At the same time a significant difference in the calculated content of the internal standard was noted – on average 1% less in archival than in new samples. This shows that the reaction occurring in the archival samples will affect the evaluation of the quality of the obtained quantitative analysis, at the same time excluding the possibility of determining the rock’s amorphous substance content with the internal standard method.

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Extraction of γ-Alumina from Low-Cost Kaolin

Resources ◽

10.3390/resources7040063 ◽

2018 ◽

Vol 7 (4) ◽

pp. 63

Author(s):

Khalil Ibrahim ◽

Mohammad Moumani ◽

Salsabeela Mohammad

Keyword(s):

Low Cost ◽

Morphological Properties ◽

X Ray Diffraction ◽

X Ray ◽

Aluminum Metal ◽

Alumina Particles ◽

Two Stages ◽

Method Of Extraction ◽

Microcrystalline Powder ◽

Made In

A combined process is proposed for the utilization of local kaolin to produce alumina particles. The applied process is made in two stages: calcination at 700 °C with sodium chloride and leaching with sulfuric followed by hydrochloric acids. The optimal extraction efficiency can be obtained when the conditions are as follows: leaching temperature is at 140 °C, leaching time is 3 h 45 min and concentration of sulfuric acid is 40 wt.%. The results show that the purity of alumina reaches 79.28%, which is suitable for the production of aluminum metal. It is evident that this method of extraction of alumina from the kaolin ash is practical and feasible. The structural and morphological properties of the calcined microcrystalline powder was characterized by X-ray diffraction and scanning electron microscope (SEM).

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Characteristics of Ni–Cr–Fe laser clad layers on EA4T steel

International Journal of Modern Physics B ◽

10.1142/s0217979217440313 ◽

2017 ◽

Vol 31 (16-19) ◽

pp. 1744031

Author(s):

Wenjing Chen ◽

Hui Chen ◽

Yongjing Wang ◽

Congchen Li ◽

Xiaoli Wang

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

X Ray Diffraction ◽

X Ray ◽

Cladding Layer ◽

Metallurgical Bonding ◽

The Matrix ◽

Feeding Speed ◽

Upper Bainite ◽

Scanning Electron

The Ni–Cr–Fe metal powder was deposited on EA4T steel by laser cladding technology. The microstructure and chemical composition of the cladding layer were analyzed by optical microscopy (OM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The bonding ability between the cladding layer and the matrix was measured. The results showed that the bonding between the cladding layer and the EA4T steel was metallurgical bonding. The microstructure of cladding layer was composed of planar crystals, columnar crystals and dendrite, which consisted of Cr2Ni3, [Formula: see text] phase, M[Formula: see text]C6 and Ni3B phases. When the powder feeding speed reached 4 g/min, the upper bainite occurred in the heat affected zone (HAZ). Moreover, the tensile strength of the joint increased, while the yield strength and the ductility decreased.

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A prototype handheld X-ray diffraction instrument

Journal of Applied Crystallography ◽

10.1107/s1600576718012943 ◽

2018 ◽

Vol 51 (6) ◽

pp. 1571-1585 ◽

Cited By ~ 1

Author(s):

Graeme Hansford

Keyword(s):

Sample Preparation ◽

Mineralogical Composition ◽

General Purpose ◽

Performance Criteria ◽

X Ray Diffraction ◽

X Ray ◽

Fine Grained ◽

Back Reflection ◽

Promising Area ◽

Sample Position

A conceptual design for a handheld X-ray diffraction (HHXRD) instrument is proposed. Central to the design is the application of energy-dispersive XRD (EDXRD) in a back-reflection geometry. This technique brings unique advantages which enable a handheld instrument format, most notably, insensitivity to sample morphology and to the precise sample position relative to the instrument. For fine-grained samples, including many geological specimens and the majority of common alloys, these characteristics negate sample preparation requirements. A prototype HHXRD device has been developed by minor modification of a handheld X-ray fluorescence instrument, and the performance of the prototype has been tested with samples relevant to mining/quarrying and with an extensive range of metal samples. It is shown, for example, that the mineralogical composition of iron-ore samples can be approximately quantified. In metals analysis, identification and quantification of the major phases have been demonstrated, along with extraction of lattice parameters. Texture analysis is also possible and a simple example for a phosphor bronze sample is presented. Instrument formats other than handheld are possible and online process control in metals production is a promising area. The prototype instrument requires extended measurement times but it is argued that a purpose-designed instrument can achieve data-acquisition times below one minute. HHXRD based on back-reflection EDXRD is limited by the low resolution of diffraction peaks and interference by overlapping fluorescence peaks and, for these reasons, cannot serve as a general-purpose XRD tool. However, the advantages ofin situ, nondestructive and rapid measurement, tolerance of irregular surfaces, and no sample preparation requirement in many cases are potentially transformative. For targeted applications in which the analysis meets commercially relevant performance criteria, HHXRD could become the method of choice through sheer speed and convenience.

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The mineralogy and firing behaviour of pottery clays of the Lake Van region, eastern Turkey

Clay Minerals ◽

10.1180/claymin.2017.052.4.04 ◽

2017 ◽

Vol 52 (4) ◽

pp. 453-468 ◽

Cited By ~ 2

Author(s):

A. Aras ◽

S. Kiliç

Keyword(s):

East Coast ◽

Chemical Characterization ◽

Mineralogical Composition ◽

Lake Van ◽

X Ray Diffraction ◽

Pottery Production ◽

X Ray ◽

Different Types ◽

Firing Shrinkage

AbstractThe present study focused on the mineralogical and chemical characterization and firing behaviour of clays from the Lake Van region and compared them with the same characteristics established for two ancient pot sherds. Four pottery clays collected from Kutki and Kuşluk in the Kesan Valley to the south, from Kavakbaşı to the southwest and from Bardakçı village on the east coast of Lake Van were analysed by X-ray diffraction to identify mineralogical composition (bulk clays and <2 μm fractions after heating at 300–500°C and ethylene glycol solvation). Further analyses were conducted to determine the size distribution, chemical composition and physical properties of test bodies derived from these clays. The in situ weathered schist forming the primary micaceous red clays which are suitable for local pottery production are characterized by large muscovite-sericite-illite and small calcite contents. In contrast, the Bardakçı clays are dominated by large smectite contents and are only used sparingly in mixtures of local pottery production because they undergo firing shrinkage and present drying and firing flaws in the fired bodies. Firing ranges of ~800–900°C were inferred from the mineralogy and colours of the two ancient sherds from Kutki. As a result of mineralogical analysis of fired and unfired test bodies of these pottery clays and pot sherds, two different types of pastes were determined for pottery production in the Lake Van region: metamorphic and volcanic paste, the former characterized by a calcite-poor and mica-sericite-rich matrix and the latter by large smectite and small calcite contents.

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Detection of Compositional Fluctuations in High Temperature Exposed Waspaloy

MRS Proceedings ◽

10.1557/proc-699-r2.6 ◽

2001 ◽

Vol 699 ◽

Author(s):

Xiaodong Zou ◽

Tariq Makram ◽

Rosario A. Gerhardt

Keyword(s):

Exposure Time ◽

Structural Integrity ◽

Thermal Exposure ◽

X Ray Diffraction ◽

X Ray ◽

Gamma Prime ◽

Distribution Shape ◽

The Matrix ◽

Quantitative Stereology ◽

Nickel Base

AbstractWaspaloy is a nickel base super-alloy used in aircraft engines. When this alloy is placed in service, it is subjected to long term exposure at high temperatures, which can cause the reinforcing gamma prime precipitate population to fluctuate and thus affect its structural integrity. The population fluctuates as a result of coarsening, dissolution or re-precipitation. Samples exposed to 1200° F for times ranging from 0 to 12626 hours were characterized using impedance spectroscopy, microhardness measurements, x-ray diffraction and quantitative stereology. Two important parameters were derived from the impedance measurements: (1) the imaginary admittance peak magnitude (Ymax) and (2) the associated relaxation frequency (fmax). As the distribution, shape and size of the precipitates change with exposure time, these parameters were also found to vary. In addition to the changes in precipitate geometry, lattice constant changes detected by analyzing x-ray diffraction data suggest that there are compositional shifts in the matrix as well as the gamma prime precipitates. Furthermore, the preferred orientation of the precipitates can also be seen to change with exposure time. These changes in composition, size and shape as a function of thermal exposure time are accompanied by changes in the volume fractions of primary and secondary gamma prime particles present. Using effective medium models, it is possible to predict that the measured properties are related to the gamma prime population. The grain boundary carbides do not appear to play any role at the conditions presented.

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