XRD and TG-DTA Study of New Phosphate-Based Geopolymers with Coal Ash or Metakaolin as Aluminosilicate Source and Mine Tailings Addition

Coal ash-based geopolymers with mine tailings addition activated with phosphate acid were synthesized for the first time at room temperature. In addition, three types of aluminosilicate sources were used as single raw materials or in a 1/1 wt. ratio to obtain five types of geopolymers activated with H3PO4. The thermal behaviour of the obtained geopolymers was studied between room temperature and 600 °C by Thermogravimetry-Differential Thermal Analysis (TG-DTA) and the phase composition after 28 days of curing at room temperature was analysed by X-ray diffraction (XRD). During heating, the acid-activated geopolymers exhibited similar behaviour to alkali-activated geopolymers. All of the samples showed endothermic peaks up to 300 °C due to water evaporation, while the samples with mine tailings showed two significant exothermic peaks above 400 °C due to oxidation reactions. The phase analysis confirmed the dissolution of the aluminosilicate sources in the presence of H3PO4 by significant changes in the XRD patterns of the raw materials and by the broadening of the peaks because of typically amorphous silicophosphate (Si–P), aluminophosphate (Al–P) or silico-alumino-phosphate (Si–Al–P) formation. The phases resulted from geopolymerisation are berlinite (AlPO4), brushite (CaHPO4∙2H2O), anhydrite (CaSO4) or ettringite as AFt and AFm phases.

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STRUCTURE AND MAGNETIC PROPERTIES OF MECHANICAL ALLOYED Mn-15at.%Al

International Journal of Nanoscience ◽

10.1142/s0219581x13500063 ◽

2013 ◽

Vol 12 (01) ◽

pp. 1350006

Author(s):

AHMED E. HANNORA ◽

FARIED F. HANNA ◽

LOTFY K. MAREI

Keyword(s):

Thermal Analysis ◽

Room Temperature ◽

Average Crystallite Size ◽

Al Alloy ◽

X Ray Diffraction ◽

X Ray ◽

Milled Sample ◽

Powder Samples ◽

Xrd Patterns ◽

Method Analysis

Mechanical alloying (MA) method has been used to produce nanocrystallite Mn -15at.% Al alloy. X-ray diffraction (XRD) patterns for the as-milled elemental α- Mn and aluminum powder samples show a mixture of α + β- MnAl phases after 20 h of milling and changes to a dominant β- MnAl phase structure after 50 h. An average crystallite size of 40 nm was determined from Hall–Williamson method analysis after 5 h of milling. Moreover, the thermal analysis results using differential thermal analysis (DTA), suggested a possible phase transformation after 20 h of milling. Isothermal treatments are carried in the temperature range of 450°C to 1000°C. Room-temperature vibrating sample magnetometer (VSM) measurements of the hysteretic response revealed that the saturation magnetization Bs and coercivity Hc for 10 h ball milled sample are ~ 2.1 emu/g and ~ 92 Oe, respectively.

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Mechanical Properties of Alkali Activated Material Based on Red Clay and Silica Gel Precursor

Environmental and Climate Technologies ◽

10.2478/rtuect-2021-0070 ◽

2021 ◽

Vol 25 (1) ◽

pp. 931-943

Author(s):

Girts Bumanis ◽

Danute Vaiciukyniene

Keyword(s):

Silica Gel ◽

Raw Materials ◽

Raw Material ◽

Alkali Activation ◽

Production Plant ◽

X Ray Diffraction ◽

Red Clay ◽

Significant Strength ◽

Naoh Solution ◽

Alkali Activated

Abstract The search for alternative alumosilicates source for production of alkali activated materials (AAM) is intensively researched. Wide spread of natural materials such as clays and waste materials are one of potential alternatives. In this research AAM was made from local waste brick made of red clay and calcined low-carbonate illite clay precursor and its properties evaluated. Waste silica gel containing amorphous silica from fertilizer production plant was proposed as additional raw material. 6 M and 7 M NaOH alkali activation solutions were used to obtain AAM. Raw materials were characterized by X-ray diffraction, laser particle size analyser, DTA/TG. Raw illite clay was calcined at a temperature of 700 to 800 °C. Waste brick was ground similar as raw clay and powder was obtained. Replacement of red clay with silica gel from 2–50 wt.% in mixture composition was evaluated. Results indicate that the most effective activator was 6 M NaOH solution and AAM with strength up to 13 MPa was obtained. Ground brick had the highest strength results and compressive strength of AAM reached 25 MPa. Silica gel in small quantities had little effect of AAM strength while significant strength reduction was observed with the increase silica gel content. The efflorescence was observed for samples with silica gel.

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Preparation and Electrochemical Performance of Mn3O4/GR Composites Electrode Material in Supercapacitors

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.807.50 ◽

2019 ◽

Vol 807 ◽

pp. 50-56

Author(s):

Yun Long Zhou ◽

Zhi Biao Hu ◽

Li Mei Wu ◽

Jiao Hao Wu

Keyword(s):

Room Temperature ◽

Raw Materials ◽

Precipitation Method ◽

Electrochemical Performances ◽

Manganese Sulfate ◽

X Ray Diffraction ◽

X Ray ◽

Co Precipitation ◽

A Current ◽

Discharge Test

Using hydrated manganese sulfate and general type graphene (GR) as raw materials, Mn3O4/GR composite has been successfully prepared by the liquid phase chemical co-precipitation method at room temperature. X-ray diffraction (XRD) was used to investigate the phase structure of Mn3O4powder and Mn3O4/GR composite; The electrochemical performances of the samples were elucidated by cyclic voltammetry and galvanostatic charge-discharge test in 0.5 mol/L Na2SO4electrolyte. The results show that the Mn3O4/GR composite possesses graphene phase and good reversibility; the composite also displays a specific capacitance of 318.8 F/g at a current density of 1 A/g.

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Physical Stability and Viscoelastic Properties of Co-Amorphous Ezetimibe/Simvastatin System

Pharmaceuticals ◽

10.3390/ph12010040 ◽

2019 ◽

Vol 12 (1) ◽

pp. 40 ◽

Cited By ~ 1

Author(s):

Justyna Knapik-Kowalczuk ◽

Krzysztof Chmiel ◽

Karolina Jurkiewicz ◽

Natália Correia ◽

Wiesław Sawicki ◽

...

Keyword(s):

Elevated Temperature ◽

Viscoelastic Properties ◽

Room Temperature ◽

Physical Stability ◽

Ternary Systems ◽

Storage Conditions ◽

X Ray Diffraction ◽

X Ray ◽

Temperature Conditions ◽

First Time

The purpose of this paper is to examine the physical stability as well as viscoelastic properties of the binary amorphous ezetimibe–simvastatin system. According to our knowledge, this is the first time that such an amorphous composition is prepared and investigated. The tendency toward re-crystallization of the amorphous ezetimibe–simvastatin system, at both standard storage and elevated temperature conditions, have been studied by means of X-ray diffraction (XRD). Our investigations have revealed that simvastatin remarkably improves the physical stability of ezetimibe, despite the fact that it works as a plasticizer. Pure amorphous ezetimibe, when stored at room temperature, begins to re-crystallize after 14 days after amorphization. On the other hand, the ezetimibe-simvastatin binary mixture (at the same storage conditions) is physically stable for at least 1 year. However, the devitrification of the binary amorphous composition was observed at elevated temperature conditions (T = 373 K). Therefore, we used a third compound to hinder the re-crystallization. Finally, both the physical stability as well as viscoelastic properties of the ternary systems containing different concentrations of the latter component have been thoroughly investigated.

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A Chemical Solution Route to Rapid Synthesis of Homogeneous Bi100−xSbx Alloys Nanoparticles at Room Temperature

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2007.151 ◽

2007 ◽

Vol 7 (2) ◽

pp. 525-529 ◽

Cited By ~ 3

Author(s):

Bo Zhou ◽

Jun-Jie Zhu

Keyword(s):

Room Temperature ◽

Raw Materials ◽

X Ray Diffraction ◽

X Ray ◽

Selected Area Electron Diffraction ◽

Transmission Electron ◽

Solution Route ◽

Diffraction Patterns ◽

Co Reduction ◽

Chemical Solution Route

A chemical co-reduction route in aqueous solution was developed to synthesize Bi100−xSbx alloys at room temperature. The hydrolyses of Bi(III) and Sb(III) were effectively avoided by selecting proper raw materials and coordinator. X-ray diffraction analysis indicated that the as-prepared Bi100−xSbx alloys were homogeneous and phase-pure, and the Bi/Sb ratios in the alloys were very close to those in the aqueous solutions. The transmission electron microscope observation showed that the as-prepared Bi100−xSbx (x = 0∼100) alloys were particles with a size of tens of nanometers. The selected area electron diffraction patterns confirmed the high crystallinity, the homogeneousness, and the composition controllability of as-prepared alloys. All these characters and the nanometer-scaled size of the alloys are believed to be beneficial to the thermoelectric property of the Bi100−xSbx alloys.

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Temperature dependence of the AV3O7 (A = Ca, Sr) structure

Acta Crystallographica Section B Structural Science ◽

10.1107/s0108768107050550 ◽

2007 ◽

Vol 63 (6) ◽

pp. 836-842 ◽

Cited By ~ 1

Author(s):

Sebastian Prinz ◽

Karine M. Sparta ◽

Georg Roth

Keyword(s):

Single Crystal ◽

Temperature Dependence ◽

Crystal Structures ◽

Room Temperature ◽

X Ray Diffraction ◽

X Ray ◽

Space Groups ◽

Temperature Ranges ◽

First Time

The V4+ (spin ½) oxovanadates AV3O7 (A = Ca, Sr) were synthesized and studied by means of single-crystal X-ray diffraction. The room-temperature structures of both compounds are orthorhombic and their respective space groups are Pnma and Pmmn. The previously assumed structure of SrV3O7 has been revised and the temperature dependence of both crystal structures in the temperature ranges 297–100 K and 315–100 K, respectively, is discussed for the first time.

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An X-ray diffraction system with controlled relative humidity and temperature

Powder Diffraction ◽

10.1017/s088571560000926x ◽

1996 ◽

Vol 11 (4) ◽

pp. 288-289 ◽

Cited By ~ 17

Author(s):

H. Hashizume ◽

S. Shimomura ◽

H. Yamada ◽

T. Fujita ◽

H. Nakazawa ◽

...

Keyword(s):

Relative Humidity ◽

Room Temperature ◽

Control Unit ◽

Saturated Water Vapor ◽

X Ray Diffraction ◽

X Ray ◽

Saturated Water ◽

Sample Chamber ◽

Diffraction Patterns ◽

Xrd Patterns

A system enabling X-ray diffraction patterns under controlled conditions of relative humidity and temperature has been devised and combined with an X-ray powder diffractometer. Relative humidity in the sample space is controlled by mixing dry N2 gas with saturated water vapor. Temperatures of the sample and inner wall of the sample chamber are monitored by two attached thermocouples and the information was fed back to the control unit. Relative humidity between 0% and the 95%, and temperature between room temperature and 60 °C can be controlled. All parameters including those for XRD are programmable and the system runs automatically. The function of the system was checked by recording the XRD patterns of montmorillonite (a clay mineral) and NaCl under increasing and decreasing relative humidity.

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Structural, magnetic and electrical properties of a new double-perovskite LaNaMnMoO 6 material

Royal Society Open Science ◽

10.1098/rsos.170920 ◽

2017 ◽

Vol 4 (11) ◽

pp. 170920 ◽

Cited By ~ 11

Author(s):

Sameh Megdiche Borchani ◽

Wissem Cheikh-Rouhou Koubaa ◽

Makrem Megdiche

Keyword(s):

Applied Field ◽

Room Temperature ◽

Double Perovskite ◽

Entropy Change ◽

Cooling Power ◽

Room Temperature Resistivity ◽

Ferromagnetic Transition ◽

X Ray Diffraction ◽

Electrical Measurements ◽

Xrd Patterns

Structural, magnetic, magnetocaloric, electrical and magnetoresistance properties of an LaNaMnMoO 6 powder sample have been investigated by X-ray diffraction (XRD), magnetic and electrical measurements. Our sample has been synthesized using the ceramic method. Rietveld refinements of the XRD patterns show that our sample is single phase and it crystallizes in the orthorhombic structure with Pnma space group. Magnetization versus temperature in a magnetic applied field of 0.05 T shows that our sample exhibits a paramagnetic–ferromagnetic transition with decreasing temperature. The Curie temperature T C is found to be 320 K. Arrott plots show that all our double-perovskite oxides exhibit a second-order magnetic phase transition. From the measured magnetization data of an LaNaMnMoO 6 sample as a function of the magnetic applied field, the associated magnetic entropy change |−ΔSM| and the relative cooling power (RCP) have been determined. In the vicinity of T C , |−ΔSM| reached, in a magnetic applied field of 8 T, a maximum value of ∼4 J kg −1 K −1 . Our sample undergoes a large magnetocaloric effect at near-room temperature. Resistivity measurements reveal the presence of an insulating-metal transition at Tρ = 180 K. A magnetoresistance of 30% has been observed at room temperature for 6 T, significantly larger than that reported for the A 2 FeMoO 6 (A = Sr, Ba) double-perovskite system.

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X-ray Diffraction of Alkali-Activated Materials with CBPD

10.20944/preprints202106.0394.v1 ◽

2021 ◽

Author(s):

Barbara Vojvodikova ◽

Lukas Prochazka ◽

Jana Bohacova

Keyword(s):

Raw Materials ◽

Research Work ◽

Sodium Metasilicate ◽

X Ray Diffraction ◽

Paper Briefly ◽

X Ray ◽

Granulated Slag ◽

Small Elements ◽

Alkali Activated ◽

Construction Practice

Alkali-activated materials are alternative building binders, where secondary raw materials are processed. Possibility to use landfilled waste materials in their preparation, increases their potential application in construction practice, and therefore they are subject to extensive research, especially in recent years. This paper briefly summarizes interesting results of an experiment aimed at verifying the possibility of applying cement by-pass dust (CBPD) in the preparation of alkali-activated materials. The research work was focused on the possibilities of using these wastes for the preparation of small elements of garden architecture. The paper briefly evaluates in particular the results of X-ray diffraction, which were subjected to three types of binder pastes differing in the amount of used activator. In the experiment, a mixture of blast furnace granulated slag, fly ash and cement by-pass dust was alkali activated with sodium metasilicate.

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Silicon −29 Solids NMR-MAS Characterization of Non-Oxide Powders and Fibers

MRS Proceedings ◽

10.1557/proc-73-165 ◽

1986 ◽

Vol 73 ◽

Cited By ~ 10

Author(s):

Kenneth E. Inkrott ◽

Stephen M. Wharry ◽

Dan J. O'Donnell

Keyword(s):

Raw Materials ◽

Synthesis Process ◽

Ceramic Fibers ◽

X Ray Diffraction ◽

Oxide Powders ◽

Ceramic Synthesis ◽

Structural Details ◽

Size Characterization ◽

Xrd Patterns

ABSTRACTPowder x-ray diffraction has been the most common method for rapid structural analysis and identification of crystalline ceramic raw materials. However, new structural ceramic raw materials often have linebroadened or featureless XRD patterns due to structural strain or small crystallite size. Characterization of various silicon carbide and silicon nitride powders and ceramic fibers by Si-29 NMR-MAS spectroscopy has revealed structural details and differences in these materials previously indistinguishable by XRD or other routine methods. Unique variables intrinsic to a given ceramic synthesis process are reflected in the NMR-MAS spectra of the resulting products.

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