scholarly journals Ostrich eggshell as calcium source for the synthesis of hydroxyapatite and hydroxyapatite partially substituted with zinc

Cerâmica ◽  
2016 ◽  
Vol 62 (364) ◽  
pp. 386-391 ◽  
Author(s):  
J. R. M. Ferreira ◽  
L. H. L. Louro ◽  
A. M. Costa ◽  
J. B. de Campos ◽  
M. H. Prado da Silva
Keyword(s):  
Xrd Analysis ◽  
Quantitative Chemical Analysis ◽  
X Ray Diffraction ◽  
Spectroscopy Technique ◽  
X Ray ◽  
Heat Treated ◽  
Before And After ◽  
Calcium Source ◽  
The Fourier Transform ◽  
Ostrich Eggshell

Abstract In the present study, hydroxyapatite and Zn-substituted hydroxyapatite powders were synthesized using ostrich eggshell as a calcium source. The samples were analyzed by scanning electron microscopy with field emission gun, and X-ray diffraction (XRD) to identify the present phases, and X-ray fluorescence spectroscopy for quantitative chemical analysis of the synthesized and heat treated powders. The Fourier transform infrared spectroscopy technique was used before and after heat treatments at 700, 900 and 1100 °C in order to identify the functional groups present, as an additional technique to the XRD analysis. The results presented in this study represent a promising method for synthesis of hydroxyapatite and hydroxyapatite partially substituted with zinc, since the results showed no undesirable phases or impurities in the produced powders. It was observed that Zn-substituted hydroxyapatite showed higher thermal stability, when compared to pure hydroxyapatite.

Semiquantitative Analysis by X-Ray Powder Diffraction (SQXRD) of the < 2 mm to 0.002 mm and < 0.002 mm Fractions of Soil

1988 ◽  
Vol 3 (3) ◽  
pp. 144-152 ◽  
Author(s):  
G. A. Raab
Keyword(s):  
Particle Size ◽  
Clay Fraction ◽  
Internal Standard ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heat Treated ◽  
Freeze Dried ◽  
Strict Protocol ◽  
Attention To Detail

AbstractThe method described in this paper is a strict protocol for X-ray diffraction (XRD) analysis of mineral phases found in soils. Its application is not restricted to soils and is an attempt to standardize XRD sample preparation and analysis. The protocol requires the particle size of the < 2 mm - 0.002 mm fraction be reduced to 0.002 mm before analysis. In die qualitative section, the clay fraction ( < 0.002 mm particle size) is prepared as oriented slides. The suspended clay fraction is saturated with ethylene glycol, K +, and Mg+2; pipeted; air-dried; heat-treated at 110°C, 350°C, and 550°C; and X-rayed at each step in order to properly identify the clay minerals. In the quantitative section, the method employs a matrix-flushing agent, corundum (Al2O3). The corundum acts also as an internal standard, a calibration standard, and a reference standard. The suspended clay fraction is freeze-dried and corundum is added to each sample. Randomly oriented powder mounts are prepared from the < 2 mm - 0.002 mm fraction, and the < 0.002 mm fraction, and X-rayed. A series of reference standards are prepared based on the existing mineralogy, corundum is added, and each mixture is X-rayed. The software integrates the area under specific peaks (chosen for intensity and no overlap) in each sample, calculates the reference intensity ratios (RIRs) and calculates the percentage of each mineral based on the equation of Chung (1974). The attention to detail allows documentation and verification of the results yielding data of known quality.

X-ray Diffraction Studies of the Axial Tensile Modulus of Rigid-Rod Polymer Fibers

1988 ◽  
Vol 134 ◽  
Author(s):  
P. Galen Lenhert ◽  
W. Wade Adams
Keyword(s):  
Tensile Modulus ◽  
Polymer Fibers ◽  
X Ray Diffraction ◽  
X Ray ◽  
Axial Tensile ◽  
Heat Treated ◽  
Before And After ◽  
Control Computer ◽  
Rigid Rod ◽  
Fiber Sample

ABSTRACTWe report the design and use of a device to measure the axial tensile modulus of high modulus fibers by following the change in the meridional X-ray spacings as a function of applied tension. The device, which mounts on a Picker 4-circle automated diffractometer, applies tension to the fiber sample by a cantilever arrangement. Tension is measured by a strain gauge bridge on the cantilever arm. The tension is adjusted and read by the control computer, a VAX 11/730. Measurements made on PBZT and PBO fibers before and after heat treatment are reported. For PBZT fibers (as spun, and heat treated at 525° C and 650° C) with tensile moduli of 186, 283 and 290 GPa, the X-ray determined moduli are 348, 385 and 395 GPa. For PBO fibers (as spun and heat treated at 600° C and 665° C) with tensile moduli of 166, 318 and 290 GPa, the X-ray determined moduli are 387, 477 and 433 GPa. These modulus values are to be compared with theoretical values presented by Wierschke in the previous paper and sonic modulus values discussed by Jiang et al in the following paper.

scholarly journals Production of Triacetin by Microwave Assisted Esterification of Glycerol Using Activated Natural Zeolite

2019 ◽  
Vol 14 (3) ◽  
pp. 672 ◽  
Author(s):  
Marwan Marwan ◽  
Eti Indarti ◽  
Darmadi Darmadi ◽  
Wahyu Rinaldi ◽  
Dzikri Hamzah ◽  
...  
Keyword(s):  
Natural Zeolite ◽  
Xrd Analysis ◽  
Molar Ratio ◽  
Catalyst Loading ◽  
X Ray Diffraction ◽  
X Ray ◽  
Microwave Assisted ◽  
Infra Red ◽  
Sem Micrograph ◽  
The Fourier Transform

Triacetin, an alternative biodiesel additive, was prepared by esterification of glycerol with acetic acid in the presence of chemically activated natural zeolite. The esterification was carried out in a small reaction flask under microwave irradiation. The catalyst was characterized for its morphology by SEM and its chemical composition by X-ray Diffraction (XRD). The Scanning Electron Microscopy (SEM) micrograph indicates improved surface area of the zeolite, while the XRD analysis shows an increase in Si/Al ratio from natural zeolite to 6.042 and its crystallinity value of 12.23%. The Fourier Transform Infra Red (FTIR) analysis obtained showed that microwave-heated samples have an esters group spectrum of triacetin at 1702 cm-1. The conversion value of glycerol was more than 95% at molar ratio of the reactants 1:9 and catalyst loading of 3%. The selectivities for monoacetin, diacetin and triacetin were 80.1%, 15.4%, and 4.5% at 60 minutes, and 43.0%, 48.6%, and 8.3% at 90 minutes. It shows that the conversion took place in consecutive steps and the use of microwave allows the reaction proceeding at milder condition. Copyright © 2019 BCREC Group. All rights reserved 

Large Size CH3NH3PbI3 Perovskite Microcrystalline with a Capsule-Free Cavity Box Structure Grown by Solvent Thermal Reaction

2021 ◽  
Vol 1032 ◽  
pp. 51-56
Author(s):  
Fei Han ◽  
Xi Ping Xi ◽  
Min Fan ◽  
Ling Ling Wang ◽  
Jin Ming Shi ◽  
...  
Keyword(s):  
Xrd Analysis ◽  
Thermal Reaction ◽  
Material Decomposition ◽  
X Ray Diffraction ◽  
X Ray ◽  
Large Size ◽  
Composition And Structure ◽  
Before And After ◽  
Box Structure ◽  
Technical Guidance

In the paper, a novel perovskite microcrystalline with a capsule-free cavity box structure was creatively prepared through solvent thermal reaction, and the composition and structure of CH3NH3PbI3 perovskite microcrystalline were further characterized by scanning electron microscope (SEM) and energy dispersive X-ray (EDX) element mapping. The SEM results show that the grain size of the prepared CH3NH3PbI3 perovskite microcrystalline is more than 100 μm. Furthermore, X-ray diffraction (XRD) analysis was used to characterize the material decomposition of perovskite microcrystals before and after 150 d of air aging. The XRD results indicate the prepared perovskite microcrystalline could be stably preserved in the air for 150 d without degradation. Our method provides technical guidance for further enriching the morphology of CH3NH3PbI3 perovskite microcrystalline.

Mineralogical Analysis of Portland Cement Pastes Rehydrated

2020 ◽  
Vol 46 (1) ◽  
pp. 15-23
Author(s):  
Tiago Assunção Santos ◽  
Guilherme Augusto de Oliveira e Silva ◽  
Daniel Véras Ribeiro
Keyword(s):  
Portland Cement ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Cement Pastes ◽  
X Ray ◽  
Curing Period ◽  
Hydraulic Binder ◽  
Before And After ◽  
Hydrated Products ◽  
Rehydration Process

Hydrated products, such as (hydrated) cement pastes, decomposition through physical-chemical alterations when submitted to high temperatures. One of the main factors that lead to microstructural changes during calcination up to 800ºC, is the dehydration phases of hydrated Portland cement. The present study sought to characterize crystalline phases occurring before and after calcination to the produced pastes using X-ray diffraction (XRD) analysis. Cement pastes were produced using Portland cement CP V-ARI RS, similar to type II (ASTM C150-07), with water/cement ratio 0.5. After a 28-day curing period, the pastes were calcinated at 800°C for 60 minutes with a 10°C/min heating rate. Afterwards, the newly produced hydraulic binder was cooled abruptly and reactivated through a rehydration process, and underwent analyses on the 7 and 28 day. During this study it was observed that the originally hydrated products can be rehydrated.

Second-Generation Aluminium Extraction Residue Used as Devitrification Aid for Glass-Ceramics

2008 ◽  
Vol 587-588 ◽  
pp. 773-777
Author(s):  
M.C. Ferreira ◽  
Wilson Acchar ◽  
Ana M. Segadães ◽  
Sonia Regina Homem de Mello-Castanho
Keyword(s):  
Second Generation ◽  
Glass Ceramics ◽  
Glass Frit ◽  
Raw Material ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heat Treated ◽  
Before And After ◽  
Devitrification Process ◽  
Extraction Metallurgy

Brazil has one of the world’s most important Bauxite deposits, the raw material for the aluminium extraction metallurgy. This work is focused on finding a suitable application for the white dross residue (WDR), a second-generation waste material produced during the metal recovery from the slag left after the primary extraction of aluminium from the ore. A commercial lime-silica based glass frit was used, to which WDR additions were made (up to 30 wt.%), aimed at studying the devitrification process of the glasses produced. Such mixtures were melted at temperatures varying from 1100 to 1500°C and the resulting fritted glasses were heat treated at 900°C. The starting materials and the mixtures thereof were characterized before and after thermal treatment by differential thermal analysis, X-ray diffraction and fluorescence, and scanning electron microscopy. The results obtained showed that the WDR is easily incorporated into the glass matrix and causes easy devitrification after short heat treatment periods at low temperature.

Preparation and characterization of 1,2,4,5-benzenetetra carboxylic-chitosan

e-Polymers ◽  
2010 ◽  
Vol 10 (1) ◽  
Author(s):  
Nurhidayatullaili Muhd Julkapli ◽  
Zulkifli Ahmad ◽  
Hazizan Md Akil
Keyword(s):  
Xrd Analysis ◽  
Absorption Capacity ◽  
Cross Linking ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
H Nmr ◽  
Crystalline Nature ◽  
The Fourier Transform

AbstractChemically cross-linked chitosan (MC) containing 1,2,4,5- benzenetetracarboxylic acid (BCA) as the cross-linking agent was prepared to improve the metal ions absorption capacity of native chitosan (NC) and limit its biodegradability. The Fourier transform infra-red (FTIR) and proton neutron magnetic resonance (1H NMR) results showed that BCA was successfully linked onto N-position of NC. The crystalline nature of NC was reduced significantly after cross-linking as examined by X-ray diffraction (XRD) analysis. Therefore, the glass transition temperature (Tg) of MC was higher than NC as reported by differential scanning calorimetry (DSC). Moreover, thermogravimetric (TGA) analysis showed that, MC had better thermal stability than NC. Morphology changes on the surface of NC and MC were characterized by field emission scanning electron microscopy (FESEM) and showed that MC had more porous surface than NC. In pH medium of 3 to 6, MC had excellent Cu (II) ions absorption capacity with a maximum 16 % higher than NC.

scholarly journals Sustainable Functionalization of PAN to Improve Tinctorial Capacity

Polymers ◽  
2021 ◽  
Vol 13 (21) ◽  
pp. 3665
Author(s):  
Vasilica Popescu ◽  
Ingrid Ioana Buciscanu ◽  
Melinda Pruneanu ◽  
Stelian Sergiu Maier ◽  
Angela Danila ◽  
...  
Keyword(s):  
Chemical Structure ◽  
Xrd Analysis ◽  
Hypervalent Iodine ◽  
X Ray Diffraction ◽  
X Ray ◽  
Yellow Orange ◽  
The Fourier Transform ◽  
Scanning Electron ◽  
Pan Fibers

This study may open a new way to obtain the coloration of a polymer during functionalization. Two polyacrylonitrile (PAN) polymers in the form of textile fibers (Melana and Dralon L) were subjected to functionalization treatments in order to improve the dyeing capacity. The functionalizations determined by an organo-hypervalent iodine reagent developed in situ led to fiber coloration without using dyes. KIO3 was formed in situ from the interaction of aqueous solutions of 3–9% KOH with 3–9% I2, at 120 °C. The yellow-orange coloration appeared as a result of the transformations in the chemical structure of each functionalized polymer, with the formation of iodinehydrin groups. The degree of functionalization directly influenced the obtained color. The results of the Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), Map and Temogravimetric Analysis (TG) plus Differential Thermal (DTA) analyses indicated the presence of new functional groups, such as iodine-oxime. The X-ray diffraction (XRD) analysis confirmed the change of the crystalline/amorphous ratio in favor of the former. The new groups introduced by functionalization make it possible to dye with classes of dyes specific to these groups, but not specific to PAN fibers, thus improving their dyeing capacity.

scholarly journals Potential Peat Clay for Minerals Source Utilized as Adsorbent and Catalyst

2019 ◽  
Vol 280 ◽  
pp. 04003
Author(s):  
Agus Mirwan ◽  
Meilana Dharma Putra ◽  
Riani Ayu Lestari
Keyword(s):  
Xrd Analysis ◽  
Sem Analysis ◽  
X Ray Diffraction ◽  
Huge Amount ◽  
Calcination Process ◽  
X Ray ◽  
Potential Source ◽  
Before And After ◽  
Flake Structure

The existence of peat clay is scattered in many parts of the world with the huge amount. The high compound of minerals in the peat clay can be potentially used as adsorbent and catalyst. This research aims to study the composition of peat clay and functional group of the compound in the peat clay. The characterization of x-ray fluorescence (XRF), fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), and scanning electron microscope-energy dispersive x-ray (SEM- EDX) were assigned to compare the sample before and after calcination process at 700 oC 120 min. FTIR analysis showed the presence of quartz, kaolinite, hematite, illite in peat clay. The results of XRF analysis showed that chemical composition of peat clay was dominantly in the form of silica oxide (18%), aluminum oxide (7%), and iron oxide (15%). The amount of compounds was observed to increase to be 32%, 18% and 11%, respectively after calcinations. XRD analysis confirmed the presence of this mineral in the peat clay. SEM analysis showed flake structure of peat clay with EDX which indicated composition of the dominant element namely the presence of Al, Si, and Fe before and after calcination. This high amount of minerals in peat clay led to potential source to be utilized as adsorbent for removing the pollutant or as and catalyst for chemical process.

Aragonite Fraction Dating of Vermetids in the Context of Paleo Sea-Level Curves Reconstruction

Radiocarbon ◽  
2020 ◽  
Vol 62 (2) ◽  
pp. 335-348
Author(s):  
Vinicius N Moreira ◽  
Kita D Macario ◽  
Renato B Guimarães ◽  
Fábio F Dias ◽  
Julia C Araujo ◽  
...  
Keyword(s):  
Sea Level ◽  
Critical Factor ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Density Separation ◽  
Level Curves ◽  
Before And After ◽  
Ams Dating ◽  
Sodium Polytungstate

ABSTRACTIdentifying and tackling recrystallization is a critical factor in the reliable radiocarbon (14C) dating of carbonates, since exogenous carbon can be incorporated and thus mask the real age of the samples. Vermetids are among the most important bioindicators used for paleo sea-level reconstruction, and the accuracy of their chronology can significantly impact sea-level curves. Age differences larger than 1 14C kyr before and after acid etching, combined with X-ray diffraction (XRD) analysis that indicates a significant amount of calcite still remains in the shell, led us to apply the previously developed carbonate density separation protocol (CarDS). Using a solution of sodium polytungstate, with density of 2.80 g/cm3, we successfully separated different carbonate fractions for a set of 10 vermetid samples from the coast of Rio de Janeiro, southeast of Brazil. Each separation was verified by XRD analysis and the 14C concentrations of different fractions were compared. The results show that the calcite fraction in the studied vermetid samples varied from 12 to 63% and aragonite fraction ages are up to 2 14C kyr older than the raw samples, thus confirming the efficacy of CarDS in removing young carbonates and the importance of density separation to vermetids prior to accelerator mass spectrometry (AMS) dating.

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