Effect of Partial Substitution of Sr by Ba on the Structural Properties of Tl0.8Ni0.2Sr2-xBrxCa2Cu3O9-δ System

In this manuscript, the effect of substituting strontium with barium on the structural properties of Tl0.8Ni0.2Sr2-xBrxCa2Cu3O9-δ compound with x= 0, 0.2, 0.4, have been studied. Samples were prepared using solid state reaction technique, suitable oxides alternatives of Pb2O3, CaO, BaO and CuO with 99.99% purity as raw materials and then mixed. They were prepared in the form of discs with a diameter of 1.5 cm and a thickness of (0.2-0.3) cm under pressures 7 tons / cm2, and the samples were sintered at a constant temperature of 860 ° C. The structural properties were studied using X-ray diffraction for all samples, and the results showed that the samples have tetragonal structure and the change of the parameters structure with the change of the barium concentration. Full Width Half Maximum (FWHM) was calculated by Orange Pro using X-RAY data. The crystal size was calculated using Scherrer and Willeamson-Heall methods, where the results showed that the crystal size, compliance and degree of crystallinity changed with the change of barium concentration, and the highest average for the crystal size was 70.0271nm at x=0, and crystallization at 61.46% at x=0.6, and the strain decreased to 0.0037 when barium concentration equals 0.4.

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Improving heat aging and mechanical properties of fluoroelastomer using carbon nanotubes

Polish Journal of Chemical Technology ◽

10.1515/pjct-2016-0050 ◽

2017 ◽

Vol 19 (1) ◽

pp. 132-142 ◽

Cited By ~ 1

Author(s):

Javad Heidarian ◽

Aziz Hassan

Keyword(s):

Crystal Size ◽

Xrd Analysis ◽

Degree Of Crystallinity ◽

X Ray Diffraction ◽

Elongation At Break ◽

X Ray ◽

Before And After ◽

The Degree Of Crystallinity ◽

Stress Induced Crystallization ◽

Induced Crystallization

Abstract Carbon nanotube (CNT)-, carbon black (CB)-filled fluoroelastomer (FE) and unfilled-FE compounds were prepared (CNT/FE, CB/FE and FE). The compounds were subjected to heat air aging and characterized by tensile test and X-Ray Diffraction (XRD) analysis. Results show that CNT improved tensile properties of FE before and after aging. All samples show stress induced crystallization (SIC) during tension. XRD results show that under all conditions, the crystals were in the form of γ-phase. For both aged and un-aged specimens, the degree of crystallinity (Xc) is low. After tensile stretching, Xc of un-aged specimens increases tremendously, with larger crystal size. Under the same conditions, the order of elongation at break (EL) was FE > CB/FE > CNT/FE. Normal modulus (NM) and tangent modulus (TM) at the same conditions was in the order of CNT/FE > CB/FE > FE. Tensile strength had the order of CNT/FE > CB/FE > FE.

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Study of gadolinium substitution effects in hexagonal yttrium manganite YMnO3

Scientific Reports ◽

10.1038/s41598-021-82621-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Dovydas Karoblis ◽

Aleksej Zarkov ◽

Edita Garskaite ◽

Kestutis Mazeika ◽

Dalis Baltrunas ◽

...

Keyword(s):

Structural Properties ◽

Sol Gel ◽

Morphological Properties ◽

Partial Substitution ◽

Substitution Effects ◽

Orthorhombic Structure ◽

X Ray Diffraction ◽

X Ray ◽

Paramagnetic Behavior ◽

Scanning Electron

AbstractIn the present work, gadolinium substitution effects on the properties of yttrium manganite YxGd1−xMn0.97Fe0.03O3 (x from 0 to 1 with a step of 0.2) synthesized by an aqueous sol–gel method have been investigated. Partial substitution of Mn3+ by 57Fe3+ in the manganite was also performed in order to investigate deeper the structural properties of synthesized compounds applying Mössbauer spectroscopy. It was demonstrated that substitution of Y3+ by Gd3+ ions leads to the changes of structural, magnetic and morphological properties of investigated system. The crystal structure gradually transformed from hexagonal to orthorhombic with an increase of Gd3+ content in the crystal lattice. The mixed phase was obtained when x = 0.6, whereas other compounds were determined to be monophasic. Magnetization measurements revealed paramagnetic behavior of all specimens, however magnetization values were found to be dependent on chemical composition of the samples. Solid solutions with orthorhombic structure revealed higher magnetization values compared to those of hexagonal samples. The highest magnetization was observed for pure GdMn0.97Fe0.03O3. Structural properties were investigated by powder X-ray diffraction, Mössbauer, FTIR and Raman spectroscopies. Morphological features of the synthesized specimens were studied by scanning electron microscopy (SEM).

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Waste and Solar Energy: An Eco-Friendly Way for Glass Melting

ChemEngineering ◽

10.3390/chemengineering5020016 ◽

2021 ◽

Vol 5 (2) ◽

pp. 16

Author(s):

Isabel Padilla ◽

Maximina Romero ◽

José I. Robla ◽

Aurora López-Delgado

Keyword(s):

Solar Energy ◽

Environmental Sustainability ◽

Raw Materials ◽

Glass Melting ◽

Glass Network ◽

X Ray Diffraction ◽

X Ray ◽

Concentrated Solar Energy ◽

Calcium Source ◽

The Aluminum Industry

In this work, concentrated solar energy (CSE) was applied to an energy-intensive process such as the vitrification of waste with the aim of manufacturing glasses. Different types of waste were used as raw materials: a hazardous waste from the aluminum industry as aluminum source; two residues from the food industry (eggshell and mussel shell) and dolomite ore as calcium source; quartz sand was also employed as glass network former. The use of CSE allowed obtaining glasses in the SiO2-Al2O3-CaO system at exposure time as short as 15 min. The raw materials, their mixtures, and the resulting glasses were characterized by means of X-ray fluorescence, X-ray diffraction, and differential thermal analysis. The feasibility of combining a renewable energy, as solar energy and different waste for the manufacture of glasses, would highly contribute to circular economy and environmental sustainability.

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Selective oxidation of cyclopentene to glutaraldehyde by H2O2 over Nb-SBA-15

New Journal of Chemistry ◽

10.1039/d1nj02427b ◽

2021 ◽

Author(s):

yingmeng qi ◽

Qi Han ◽

li wu ◽

Jun Li

Keyword(s):

Structural Properties ◽

Selective Oxidation ◽

Mesoporous Materials ◽

Hydrothermal Process ◽

X Ray Diffraction ◽

X Ray

A series of niobium-containing mesoporous materials Nb-SBA-15 have been prepared by sonication–impregnation and hydrothermal process. The dispersion and structural properties of niobium-containing species were systematically characterized by X-ray diffraction, scanning...

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Polyurethane Composite Foams Synthesized Using Bio-Polyols and Cellulose Filler

Materials ◽

10.3390/ma14133474 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3474

Author(s):

Katarzyna Uram ◽

Milena Leszczyńska ◽

Aleksander Prociak ◽

Anna Czajka ◽

Michał Gloc ◽

...

Keyword(s):

Cross Sections ◽

Raw Materials ◽

Polyurethane Foams ◽

Degree Of Crystallinity ◽

X Ray Diffraction ◽

Polyurethane Composite ◽

Composite Foams ◽

Closed Cell ◽

Ft Ir ◽

The Fourier Transform

Rigid polyurethane foams were obtained using two types of renewable raw materials: bio-polyols and a cellulose filler (ARBOCEL® P 4000 X, JRS Rettenmaier, Rosenberg, Germany). A polyurethane system containing 40 wt.% of rapeseed oil-based polyols was modified with the cellulose filler in amounts of 1, 2, and 3 php (per hundred polyols). The cellulose was incorporated into the polyol premix as filler dispersion in a petrochemical polyol made using calenders. The cellulose filler was examined in terms of the degree of crystallinity using the powder X-ray diffraction PXRD -and the presence of bonds by means of the fourier transform infrared spectroscopy FT-IR. It was found that the addition of the cellulose filler increased the number of cells in the foams in both cross-sections—parallel and perpendicular to the direction of the foam growth—while reducing the sizes of those cells. Additionally, the foams had closed cell contents of more than 90% and initial thermal conductivity coefficients of 24.8 mW/m∙K. The insulation materials were dimensionally stable, especially at temperatures close to 0 °C, which qualifies them for use as insulation at low temperatures.

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Study on the Electrical, Structural, Chemical and Optical Properties of PVD Ta(N) Films Deposited with Different N2 Flow Rates

Coatings ◽

10.3390/coatings11080937 ◽

2021 ◽

Vol 11 (8) ◽

pp. 937

Author(s):

Yingying Hu ◽

Md Rasadujjaman ◽

Yanrong Wang ◽

Jing Zhang ◽

Jiang Yan ◽

...

Keyword(s):

Crystal Structure ◽

Optical Properties ◽

Photoelectron Spectroscopy ◽

Crystal Size ◽

Silicon Substrates ◽

X Ray Diffraction ◽

Dc Magnetron Sputtering ◽

Flow Rates ◽

X Ray ◽

N2 Flow Rate

By reactive DC magnetron sputtering from a pure Ta target onto silicon substrates, Ta(N) films were prepared with different N2 flow rates of 0, 12, 17, 25, 38, and 58 sccm. The effects of N2 flow rate on the electrical properties, crystal structure, elemental composition, and optical properties of Ta(N) were studied. These properties were characterized by the four-probe method, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and spectroscopic ellipsometry (SE). Results show that the deposition rate decreases with an increase of N2 flows. Furthermore, as resistivity increases, the crystal size decreases, the crystal structure transitions from β-Ta to TaN(111), and finally becomes the N-rich phase Ta3N5(130, 040). Studying the optical properties, it is found that there are differences in the refractive index (n) and extinction coefficient (k) of Ta(N) with different thicknesses and different N2 flow rates, depending on the crystal size and crystal phase structure.

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Mining Wastes of an Albite Deposit as Raw Materials for Vitrified Mullite Ceramics

Minerals ◽

10.3390/min11030232 ◽

2021 ◽

Vol 11 (3) ◽

pp. 232

Author(s):

Pedro J. Sánchez-Soto ◽

Eduardo Garzón ◽

Luis Pérez-Villarejo ◽

George N. Angelopoulos ◽

Dolores Eliche-Quesada

Keyword(s):

Particle Size ◽

Raw Materials ◽

Phase Evolution ◽

Particle Size Analysis ◽

Size Analysis ◽

Mining Wastes ◽

X Ray Diffraction ◽

X Ray ◽

Maximum Value

In this work, an examination of mining wastes of an albite deposit in south Spain was carried out using X-ray Fluorescence (XRF), X-ray diffraction (XRD), particle size analysis, thermo-dilatometry and Differential Thermal Analysis (DTA) and Thermogravimetric (TG) analysis, followed by the determination of the main ceramic properties. The albite content in two selected samples was high (65–40 wt. %), accompanied by quartz (25–40 wt. %) and other minor minerals identified by XRD, mainly kaolinite, in agreement with the high content of silica and alumina determined by XRF. The content of Na2O was in the range 5.44–3.09 wt. %, being associated with albite. The iron content was very low (<0.75 wt. %). The kaolinite content in the waste was estimated from ~8 to 32 wt. %. The particle size analysis indicated values of 11–31 wt. % of particles <63 µm. The ceramic properties of fired samples (1000–1350 °C) showed progressive shrinkage by the thermal effect, with water absorption and open porosity almost at zero at 1200–1250 °C. At 1200 °C, the bulk density reached a maximum value of 2.38 g/cm3. An abrupt change in the phase evolution by XRD was found from 1150 to 1200 °C, with the disappearance of albite by melting in accordance with the predictions of the phase diagram SiO2-Al2O3-Na2O and the system albite-quartz. These fired materials contained as main crystalline phases quartz and mullite. Quartz was present in the raw samples and mullite was formed by decomposition of kaolinite. The observation of mullite forming needle-shape crystals was revealed by Scanning Electron Microscopy (SEM). The formation of fully densified and vitrified mullite materials by firing treatments was demonstrated.

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Effect of the BSCCO superconducting properties by tiny Y2O3 addition

Modern Physics Letters B ◽

10.1142/s0217984916503280 ◽

2016 ◽

Vol 30 (26) ◽

pp. 1650328

Author(s):

Yan Dong ◽

Aimin Sun ◽

Bin Xu ◽

Hongtao Zhang ◽

Meng Zhang

Keyword(s):

Volume Fraction ◽

Superconducting Properties ◽

X Ray Diffraction ◽

Critical Transition Temperature ◽

Solid State Reaction Technique ◽

X Ray ◽

Oxide Addition ◽

One Step ◽

Step Transition ◽

Y2o3 Addition

In this paper, the effect of tiny Y2O3 addition in (Bi,[Formula: see text]Pb)-2223 superconductor prepared by solid state reaction technique was studied. The properties of samples have been investigated via X-ray diffraction (XRD), resistance–temperature ([Formula: see text]–[Formula: see text]) curve, scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). XRD data indicated that all samples are multiphase and the major phases are high-temperature phases and low-temperature phases. The volume fraction of (Bi,[Formula: see text]Pb)-2223 is not great change with tiny Y2O3 addition. All samples exhibit superconducting phase with the critical transition temperature and one-step transition, however, the transition width was decreased with the Y2O3 addition up to 0.04 wt.% and sharp increased with the excessive oxide addition. SEM pictures show that the Y2O3 appeared on the flake-type grains surface obviously, but the number and size of the hole between grains are decreased in the 0.04 wt.% addition.

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Structural properties of the guest species in diacyl peroxide/urea inclusion compounds: an X-ray diffraction investigation

Proceedings of the Royal Society of London. Series A: Mathematical and Physical Sciences ◽

10.1098/rspa.1990.0129 ◽

1990 ◽

Vol 431 (1882) ◽

pp. 245-269 ◽

Cited By ~ 31

Keyword(s):

Single Crystal ◽

Structural Properties ◽

Inclusion Compounds ◽

X Ray Diffraction ◽

Channel Axis ◽

Guest Molecules ◽

X Ray ◽

Urea Inclusion Compounds ◽

Diacyl Peroxide ◽

Urea Inclusion

In this paper we report single crystal X-ray diffraction studies of urea inclusion compounds containing diacyl peroxides (dioctanoyl peroxide (OP), diundecanoyl peroxide (UP), lauroyl peroxide (LP)) as the guest component. In these inclusion compounds, the host (urea) molecules crystallize in a hexagonal structure that contains linear, parallel, non-intersecting channels (tunnels). The guest (diacyl peroxide) molecules are closely packed inside these channels with a periodic repeat distance that is incommensurate with the period of the host structure along the channel axis. Furthermore, there is pronounced inhomogeneity within the guest structure: within each single crystal, there are regions in which the guest molecules are three-dimensionally ordered, and other regions in which they are only one-dimensionally ordered (along the channel axis). Although it has not proven possible to ‘determine’ the guest structures in the conventional sense, substantial information concerning their average periodicities and their orientational relationships with respect to the host has been deduced from single crystal X-ray diffraction photographs recorded at room temperature. For OP/urea, UP/urea and LP/urea, the guest structure in the three-dimensionally ordered regions is monoclinic, and six types of domain of this monoclinic structure can be identified within each single crystal. The relative packing of diacyl peroxide molecules is the same in each domain, and the different domains are related by 60° rotation about the channel axis. For each of these inclusion compounds, the offset between the ‘heights’ of the guest molecules in adjacent channels is the same ( ca . 4.6 Å (4.6 x 10 -10 m)) within experimental error, suggesting that the relative interchannel packing of the guest molecules is controlled by a property of the diacyl peroxide group. In addition to revealing these novel structural properties, the work discussed in this paper has more general relevance concerning the measurement and interpretation of single crystal X-ray diffraction patterns that are based on more than one three-dimensionally periodic reciprocal lattice. Seven separate reciprocal lattices are required to rationalize the complete X-ray diffraction pattern from each diacyl peroxide/urea crystal studied here.

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Mechanical and Structural Properties of Superhard TiAlSiN Coatings Deposited by Arc Ion Plating of Cylindrical Cathode

Materials Science Forum ◽

10.4028/www.scientific.net/msf.783-786.1426 ◽

2014 ◽

Vol 783-786 ◽

pp. 1426-1431

Author(s):

Wang Ryeol Kim ◽

Min Chul Kwon ◽

Jung Hoon Lee ◽

Uoo Chang Jung ◽

Won Sub Chung

Keyword(s):

Structural Properties ◽

Nitrogen Pressure ◽

Structural Features ◽

X Ray Diffraction ◽

X Ray ◽

Ion Plating ◽

Arc Current ◽

Cathode Arc ◽

Cathodic Arc ◽

Tialsin Coating

TiAlSiN coatings were deposited on WC-Co metal by using a cathodic arc ion deposition method of cylindrical cathode. We used Ti / Al (50 / 50 at.%) arc target and silicon sputter target. The influence of the nitrogen pressure, TiAl cathode arc current, bias voltage, and deposition temperature on the mechanical and the structural properties of the films were investigated. The structural features of the films were investigation in detail using X-ray diffraction. And coatings were characterized by means of FE-SEM, nanoindentation, Scratch tester, Tribology tester, XRD and XPS. The hardness of the film reached 43 GPa at the cathode arc current of 230 A and decreased with a further increase of the arc current. And the adhesion of the film reached 34 N. The results showed that the TiAlSiN coating exhibited an excellent mechanical properties which application for tools and molds.

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