Influence of Citric Acid on the Formation of Hydroxyapatite Powders by Using Ca(NO3)2-P2O5 Ethanol Solution System

2010 ◽  
Vol 152-153 ◽  
pp. 1248-1252
Author(s):  
Qing Chang ◽  
Hong Qiang Ru ◽  
Liang Yu ◽  
Ji Guang Li
Keyword(s):  
Particle Size ◽  
Citric Acid ◽  
Sol Gel ◽  
Xrd Analysis ◽  
Transformation Process ◽  
Ethanol Solution ◽  
X Ray Diffraction ◽  
Solution System ◽  
Ca Addition ◽  
Xrd Patterns

In this study, nano-hydroxyapatite (HA) powders were synthesized via a simple sol-gel method using Ca(NO3)2•4H2O and P2O5 as starting materials. Two different precursors, with and without citric acid (CA), were prepared. The transformation process of HA from precursors, purity and particle size of the obtained HA powders were evaluated. HA derived from the precursor with CA showed a different transformation process from that without CA. It was observed that the content of CaO as an unavoidable major impurity was reduced due to the addition of CA. In the calcined powders from the CA-free precursor, X-ray diffraction (XRD) patterns revealed an intense CaO peak. For the calcined powders from the CA-addition precursor, XRD analysis showed a very weak CaO peak. It was also found that the synthesized HA powders from precursor with CA were finer than those without CA. The mechanism of the influence of CA on the formation, purity and particle size distribution of HA powders was discussed.

scholarly journals Synthesis of lead-based 1212 and 3212 superconductors by an aqueous sol-gel method

2009 ◽  
Vol 7 (3) ◽  
pp. 362-368 ◽  
Author(s):  
Giedre Nenartaviciene ◽  
Ramunas Skaudzius ◽  
Rimantas Raudonis ◽  
Aivaras Kareiva
Keyword(s):  
Sol Gel ◽  
Xrd Analysis ◽  
Structural Features ◽  
Complexing Agents ◽  
X Ray Diffraction ◽  
X Ray ◽  
Resistivity Measurements ◽  
Ceramic Samples ◽  
Xrd Patterns ◽  
Sol Gel Synthesis

AbstractThe aqueous sol-gel synthesis technique for the preparation of (Pb,Sr)Sr2(Y,Ca)Cu2O7±x (Pb-1212) and (Pb2,Cu)Sr2(Y,Ca)Cu2O8±x (Pb-3212) superconductors using two different complexing agents, namely 1,2-ethanediol and tartaric acid was studied. The phase transformations, composition and micro-structural features in the polycrystalline samples were studied by powder X-ray diffraction analysis (XRD), infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). XRD analysis of the ceramic samples obtained by calcination of Pb-Sr-Y-Ca-Cu-O acetate-glycolate precursor gels in air, for 10 hours at 800°C and at 825°C, showed the presence of homogeneous Pb-1212 and Pb-3212 crystallites as major phases. The XRD patterns of the ceramics obtained from Pb-Sr-Y-Ca-Cu-O acetate-tartrate precursor gels, however, showed multiphasic character. The critical temperature of superconductivity (TC (onset)) observed by resistivity measurements were found to be 91 K and 75 K for Pb-1212 and Pb-3212 samples, respectively.

Modified Sol-Gel Production of Nano SDC20 Materials

2014 ◽  
Vol 938 ◽  
pp. 19-23
Author(s):  
S. Ramesh ◽  
K.C. James Raju ◽  
C. Vishnuvardhan Reddy
Keyword(s):  
Particle Size ◽  
High Purity ◽  
Large Scale ◽  
Sol Gel ◽  
Xrd Analysis ◽  
Scale Production ◽  
Large Scale Production ◽  
Sol Gel Process ◽  
Xrd Patterns ◽  
Increasing Temperature

The production of high purity samarium doped ceria (SDC20, Sm0.2Ce0.8O2-δ) nanopowders by modified sol-gel process using maltose and pectin as organic precursors. Around, 6 nm particle size can be obtained after calcination of the as synthesized (pre dried) gel at 500 °C for 2 h. Rietveld refinement of Powder X-ray diffraction (XRD) patterns confirms the cubic structure with single phase. Chemical composition of SDC20 is in good agreement with EDX measurements. TEM and XRD analysis indicate the influence of sintering temperature on particle size, which increases with increasing temperature. This modified sol-gel process is a non-toxic and environmentally friendly for large-scale production of high purity nanopowders.

scholarly journals Modification in Structural, Morphological, Magnetic and Ferroelectric Properties of Calcium-Doped Bismuth Ferrite Nanoparticles

2020 ◽  
Vol 11 (1) ◽  
pp. 123-131
Author(s):  
Nushrat Naushin ◽  
Sadi Md Shahriar ◽  
Oishy Roy ◽  
Ahmed Sharif
Keyword(s):  
Particle Size ◽  
Hysteresis Loop ◽  
Bismuth Ferrite ◽  
Ferroelectric Properties ◽  
Sol Gel ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Current Characteristics ◽  
Limiting Value

The structural, morphological, magnetic and ferroelectric properties of calcium (Ca) doped bismuth ferrite (BFO) synthesized using a sol-gel method were studied. X-ray diffraction (XRD) analysis followed by Rietveld refinement revealed the lattice distortion of BFO after doping with 6% and 8% Ca. This also led to the reduction in particle size by creating oxygen vacancies, which was observed from the surface morphology using Field Emission Scanning Electron Microscopy (FESEM). The Magnetic properties exhibited some enhancements in saturation magnetization when the particle size was near a limiting value. The reduction in the coercive magnetic field with the increase in dopant concentration was also evident from the M-H hysteresis loop measured by Vibrating Sample Magnetometer (VSM). The Ferroelectric P-E hysteresis loop exhibited an increased symmetry in the hysteresis loop and increase in the polarization with the increase in %Ca. The 8% Ca doped BFO exhibited an incomplete saturation in the hysteresis loop and was evident to exhibit leakage current characteristics. Journal of Engineering Science 11(1), 2020, 123-131

Synthesis, Characterization and Properties of PANI/(La-Nd Doped BaFe12O19) Composites

2017 ◽  
Vol 727 ◽  
pp. 327-334
Author(s):  
Yan Wang ◽  
Jun Wang ◽  
Xiao Fei Zhang ◽  
Ya Qing Liu
Keyword(s):  
Sol Gel ◽  
Network Analyzer ◽  
X Ray Diffraction ◽  
Sem Images ◽  
Structure Morphology ◽  
Xrd Patterns ◽  
Hexagonal Platelet ◽  
Peak Value ◽  
Properties Of Composites

La-Nd co-doped barium hexaferrites, Ba0.7(LamNdn)0.3Fe12O19 (D-BaM), were successfully prepared by sol-gel method. PANI / D-BaM composites were synthesized by in-situ polymerization in solution. The structure, morphology and properties of samples have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), four-probe conductivity tester and vector network analyzer. The XRD patterns showed that the crystal structure of all the samples exist as M-type phases. The SEM images revealed that the particles presented a hexagonal platelet-like morphology. The magnetic properties could be improved by substitutions of La and Nd ions. The saturation magnetization (Ms) and coercive force (Hc) increased with the change of La / Nd ratio to the maximum at La / Nd = 3:1. The doped particles have also been embedded in conductive PANI to prepare electromagnetic materials, and the conductivity kept on the order of 10-2. The microwave absorbing properties of composites at 30 MHz-6 GHz improved obviously, the peak value of reflection loss could reach-7.5 dB.

The effect of silver concentration and calcination temperature on structural and optical properties of ZnO:Ag nanoparticles

2015 ◽  
Vol 29 (01) ◽  
pp. 1450254 ◽  
Author(s):  
M. Shayani Rad ◽  
A. Kompany ◽  
A. Khorsand Zak ◽  
M. E. Abrishami
Keyword(s):  
Calcination Temperature ◽  
Sol Gel ◽  
Visible Emission ◽  
X Ray Diffraction ◽  
Ag Nps ◽  
Zno Nps ◽  
Calcination Temperatures ◽  
Transmission Electron ◽  
Xrd Patterns ◽  
Average Size

Pure and silver added zinc oxide nanoparticles ( ZnO -NPs and ZnO : Ag -NPs) were synthesized through a modified sol–gel method. The prepared samples were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM) and photoluminescence (PL) spectroscopy. In the XRD patterns, silver diffracted peaks were also observed for the samples synthesized at different calcination temperatures of 500°C, 700°C, 900°C except 1100°C, in addition to ZnO . TEM images indicated that the average size of ZnO : Ag -NPs increases with the amount of Ag concentration. The PL spectra of the samples revealed that the increase of Ag concentration results in the increase of the visible emission intensity, whereas by increasing the calcination temperature the intensity of visible emission of the samples decreases.

Structural, Magnetic and Dielectric Analysis of Higher Magnetic Mn Doped Zn-Cr Oxide Nanoparticles

2021 ◽  
Vol 9 (VI) ◽  
pp. 95-102
Author(s):  
S. D. Balsure
Keyword(s):  
Type Strain ◽  
Sol Gel ◽  
Hexagonal Wurtzite Structure ◽  
Xrd Analysis ◽  
Oxide Nanoparticles ◽  
X Ray Diffraction ◽  
Microstructural Parameters ◽  
Auto Combustion ◽  
Mn Doped ◽  
Combustion Technique

Higher magnetic Mn doped Zn-Cr oxide nanoparticles with general compositional formula MxZn0.95-xCr0.05O have been synthesized by using sol-gel auto combustion technique. Room temperature X-ray diffraction (XRD) technique has been employed to study the structural and microstructural parameters of the as-prepared samples. XRD analysis confirms the phase purity and hexagonal wurtzite structure of all the samples. Replacement of Zn2+ ions by Mn2+ ions shifts peak positions slightly towards the lower angles which in turn expands the lattice lengths ‘a’ from 3.2487 to 3.2528 Å and ‘c’ from 5.2043 to 5.2118 Å. Crystallite size obtained from Scherrer equation was confirmed by Williamson – Hall (W-H) and size – strain plot methods (SSP). Both W-H and SSP methods reveals the tensile type strain for undoped sample and comprehensive type strain for Mn2+ doped samples. Magnetic properties were investigated by using vibrating sample magnetometer. Diluted ferromagnetic behaviour is observed for all the samples and saturation magnetization (MS) increases from 0.0514 to 0.1163 emu/gm. Two-probe technique was employed to understand the dielectric behaviour of the samples as a function of frequency. At lower frequency region, both dielectric constant () and dielectric loss tangent (tan ) shows higher values and decreases with the increasing applied frequency.

scholarly journals Effect of the suspension of Ag-incorporated TiO2 nanoparticles (Ag-TiO2 NPs) on certain growth, physiology and phytotoxicity parameters in spinach seedlings

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0244511
Author(s):  
Fernando Gordillo-Delgado ◽  
Jakeline Zuluaga-Acosta ◽  
Gonzalo Restrepo-Guerrero
Keyword(s):  
Particle Size ◽  
Titanium Dioxide Nanoparticles ◽  
Germination Rate ◽  
Sol Gel ◽  
Control Group ◽  
Human Consumption ◽  
X Ray Diffraction ◽  
X Ray ◽  
Growth Physiology ◽  
Powder Samples

In this work, the effect of the inoculation of silver-incorporated titanium dioxide nanoparticles (Ag-TiO2 NPs) in spinach seeds was evaluated on certain growth, physiology and phytotoxicity parameters of the plants. This is an important crop for human consumption with high nutritional value due to their low calorie and fat content, providing various vitamins and minerals, especially iron. These NPs were obtained by means of the sol-gel method and heat treatment; the resulting powder material was characterized using X-ray diffraction and scanning electron microscopy and the influence of these NPs on plants was measured by estimating the germination rate, monitoring morphological parameters and evaluating phytotoxicity. The photosynthetic activity of the spinach plants was estimated through the quantification of the Ratio of Oxygen Evolution (ROE) by the photoacoustic technique. Samples of TiO2 powder with particle size between 9 and 43 nm were used to quantify the germination rate, which served to determine a narrower size range between 7 and 26 nm in the experiments with Ag-TiO2 NPs; the presence of Ag in TiO2 powder samples was confirmed by energy-dispersive X-ray spectroscopy. The analysis of variance showed that the dependent variable (plant growth) could be affected by the evaluated factors (concentration and size) with significant differences. The statistical trend indicated that the application of the Ag-TiO2 NPs suspension of lowest concentration and smallest particle size could be a promoting agent of the growth and development of these plants. The inoculation with NPs of 8.3 nm size and lowest concentration was related to the highest average ROE value, 24.6 ± 0.2%, while the control group was 20.2 ± 0.2%. The positive effect of the Ag-TiO2 NPs treatment could be associated to the generation of reactive oxygen species, antimicrobial activity, increased biochemical attributes, enzymatic activity or improvements in water absorption.

scholarly journals Effect of Re and Tm-site on morphology structure and optical band gap of ReTmO3 (Re: La, Ce, Nd, Gd, Dy, Y and Tm: Fe, Cr) prepared by sol-gel method

2018 ◽  
Vol 64 (4) ◽  
pp. 381
Author(s):  
Muhammad Tufiq Jamil ◽  
Javed Ahmad ◽  
Syed Hamad Bukhari ◽  
Murtaza Saleem
Keyword(s):  
Band Gap ◽  
Sol Gel ◽  
Xrd Analysis ◽  
Sem Analysis ◽  
X Ray Diffraction ◽  
Orthorhombic Crystal ◽  
X Ray ◽  
Average Grain Size ◽  
Auto Combustion ◽  
Uv Visible

Rare earth nano sized pollycrystalline orthoferrites and orthocromites ReT mO3 (Re = La, Nd, Gd, Dy, Y and T m = Fe, Cr) have been synthesized by sol-gel auto combustion citrate method. The samples have been characterized by means of X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), and UV-visible spectroscopy. The samples are single phase as confirmed by XRD analysis and correspond to the orthorhombic crystal symmetry with space group pbnm. Debye Scherer formula and Williamson Hall analysis have been used to calculate the average grain size which is consistent with that of determined from SEM analysis and varied between 25-75 nm. The elemental compositions of all samples have been checked by EDX analysis. Different crystallographic parameters are calculated with strong structural correlation among Re and Tm sites. The optical energy band gap has been calculated by using Tauc relation estimated to be in the range of 1.77 - 1.87 eV and 2.77 - 3.14 eV, for ReFeO3 and ReCrO3, respectively.

Synthesis and Characterization of Cadmium with Titanium Oxide (Cd-TiO2) Nanocomposite: Testing its Antibacterial Effect

2021 ◽  
Vol 12 (4) ◽  
pp. 2523-2529
Author(s):  
Daniel Sam N ◽  
Anish C I ◽  
Sabeena G ◽  
Rajaduraipandian S ◽  
Manobala ◽  
...  
Keyword(s):  
Sol Gel ◽  
Gram Negative Bacteria ◽  
X Ray Diffraction ◽  
Sem Images ◽  
Gram Negative ◽  
X Ray ◽  
Weight Percentage ◽  
Inhibition Concentration ◽  
Xrd Patterns

Sol gel methods were used for the study of the antimicrobial activity of Cd-TiO2 against gram-negative and positive bacteria. These Cd-TiO2 have been characterized by various optical and techniques. They have been exhibited by X-ray diffraction, scanning electron microscopy, ultraviolet spectroscopy, and infrared spectroscopy. The structures of the various XRD patterns indicate that the product has a structure. The particle size of Cd-TiO2 is 35nm. The SEM images confirm the spherical appearance of the sample. The energy X-ray spectra have been confirmed as well and then C, O, Ti, Cd, Pt element are present in Cd-TiO2. The weight percentage of Cadmium is 5.8%, Ti is 51.03%, C is 5.13% and O is 31.75% in Cd-TiO2. BET image shows that the major pore size distribution of Cd-TiO2 is ranged from 2.24 nm. The Cd-TiO2 that the antibacterial activity when tested against the pathogens only gram-negative bacteria such as Pseudomonas. The zone of minimum inhibition concentration was measured in a range of 20mm in 25μl and 30mm in 100μl.

Analysis of Selected Area Diffraction Patterns With Winjade

1998 ◽  
Vol 4 (S2) ◽  
pp. 342-343 ◽  
Author(s):  
S. D. Walck ◽  
P. Ruzakowski-Athey
Keyword(s):  
Single Phase ◽  
Xrd Analysis ◽  
Analysis Program ◽  
X Ray Diffraction ◽  
Program Module ◽  
Vast Number ◽  
One Dimensional ◽  
X Ray ◽  
Diffraction Patterns ◽  
Xrd Patterns

The analysis of Selected Area Diffraction (SAD) patterns that are collected from a single phase material having sufficient crystallites to provide continuous rings is relatively straightforward. However, when this condition is not met and there may be several phases present having rings of a spotty nature, the pattern is complex and can be quite difficult to analyze manually because of the vast number of discrete spots. WinJade from MDI is an X-ray diffraction (XRD) analysis program with an Electron Diffraction Program Module (EDPM) that can be used to aid in the analysis of SAD patterns. The EDPM produces Integrated Circular Density Plots (ICDP), which are one-dimensional intensity profiles plotted as a function of equivalent XRD 20 values or crystal d-spacings. These ICDP's can be overlayed with XRD patterns or with reference lines from the NIST and JCPDS crystalline databases for direct comparisons.

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