Sintering Kinetics of Hydroxyapatite Prepared by Chemical Coprecipitation Method

2011 ◽  
Vol 233-235 ◽  
pp. 1511-1515 ◽  
Author(s):  
Jian Peng Zou
Keyword(s):  
Particle Size ◽  
Sintering Temperature ◽  
Average Particle Size ◽  
Atomic Emission ◽  
Coprecipitation Method ◽  
Average Particle ◽  
Chemical Coprecipitation ◽  
Particle Size Analyzer ◽  
Controlling Mechanism ◽  
Chemical Coprecipitation Method

With chemical coprecipitation method, high purity hydroxyapatite was successfully prepared in this paper. The microstructure and components of HA were characterized by XRD, SEM, FTIR, atomic emission spectrum and particle size analyzer. The results demonstrate that synthesized HA is very pure and is harmless to human body. Average particle size of HA powder is about 10.4μm. Crystallization degree of hydroxyapatite increases with the increase of sintering temperature and the optimal preparing technique is sintering at 750 for 2h with temperature-rising rate of 5°C·min-1. Grain growing activation energy of HA can be calculated as 24.8 kJ·mol-1 according to the relationship between grain size and sintering temperature. HA’s grain growth mechanism is interfacial diffusion controlling mechanism.

scholarly journals Synthesis of Zinc Sulfide Nanoparticles by Chemical Coprecipitation Method and its Bactericidal Activity Application

2019 ◽  
Vol 9 (2) ◽  
pp. 156-160
Author(s):  
Razhan S. Othman ◽  
Rebaz A. Omar ◽  
Karzan A. Omar ◽  
Aqeel I. Gheni ◽  
Rekar Q. Ahmad ◽  
...  
Keyword(s):  
Zinc Sulfide ◽  
Average Particle Size ◽  
Coprecipitation Method ◽  
Diffusion Method ◽  
Average Particle ◽  
Zns Nanoparticles ◽  
Sulfate Heptahydrate ◽  
X Ray ◽  
Chemical Coprecipitation ◽  
Chemical Coprecipitation Method

A particle of zinc sulfide (ZnS) was synthesized by the chemical coprecipitation method using zinc sulfate heptahydrate (ZnSO4), ammonium sulfate (NH4)2SO4 as a reactant, and thiourea as a stabilizer and capping agent. The optioned product characterized by electron dispersive X-ray spectroscopy that exhibits the presence of Zn and S elements. The average particle size of the ZnS nanoparticles determined using X-ray diffraction is about 4.9 nm. The ultraviolet–visible spectroscopy showed the blue shift in wavelength and the band gap was 4.33 eV, the surface morphology of the synthesized ZnS nanoparticles powder was studied by scan electron microscopy which was showed the irregular and some spherical shapes of ZnS in a nanosized range. The Fourier-transform infrared spectroscopy observed an absorption peck at 657.73 and 613.36 cm−1 that were assigned to the stretching mods of the Zn-S band. The different amounts of ZnS nanoparticle were applied as bactericidal against Staphylococcus aureus by disk diffusion method. It displayed activity against S. aureus bacteria, which was carried out in the absence of irradiation.

Fe3O4 Magnetic Preparation by Bauxite Ore Washing Fine Mud

2014 ◽  
Vol 1010-1012 ◽  
pp. 961-965
Author(s):  
Jian Qiang Xiao ◽  
Guo Wei He ◽  
Yan Jin Hu
Keyword(s):  
Particle Size ◽  
Aging Time ◽  
Average Particle Size ◽  
Xrd Analysis ◽  
Test Methods ◽  
Raw Material ◽  
Molar Ratio ◽  
Average Particle ◽  
Experimental Conditions ◽  
Particle Size Analyzer

Bauxite waste sludge as a raw material, the use of reverse chemical coprecipitation synthesize Fe3O4. Researching temperature, precipitation concentration, aging time and Fe2+/Fe3+ molar ratio effect on the particle size, morphology. Optimal experimental conditions: temperature 70 °C, the precipitant NaOH mass ratio of 10%, aging time 3h, Fe2+/Fe3+ molar ratio of 2:3. Test methods using a laser particle size analyzer, XRD analysis of the products were characterized, the product is Fe3O4, the average particle size of 0.11mm.

scholarly journals Preparation of ultrafine iron phosphate micro-powder from phosphate slag

2018 ◽  
Vol 238 ◽  
pp. 02002
Author(s):  
Fangjing Sun ◽  
Yi Zhang ◽  
Jiawei Zhang ◽  
Xixi Yan ◽  
Xiaoyu Liu ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Particle Size ◽  
Electron Microscope ◽  
Average Particle Size ◽  
Iron Phosphate ◽  
Average Particle ◽  
X Ray ◽  
Particle Size Analyzer ◽  
Phosphate Slag ◽  
Scanning Electron

In this experiment, ultrafine iron phosphate micro-powder was prepared by hydrothermal method which used phosphate slag as an iron source. The effects of reaction temperature, surfactants type and amount on its particle size were explored. The samples were characterized by using Malvern Laser Particle Size Analyzer (MS2000), X-Ray Diffractometer (XRD), Scanning Electron Microscope (SEM) and Energy Dispersive X-Ray Spectroscopy (EDX).The results showed that at 160 °C, 1 wt%CTAB, monoclinic iron phosphate micro-powder was obtained with an average particle size about 0.4 μm which also has a good dispersion in aqueous solution.

Facile Synthesis and Characterization of Fe-Co Nanoparticles Supported Silica Rice Husk

2016 ◽  
Vol 709 ◽  
pp. 66-69
Author(s):  
Jeyashelly Andas ◽  
Rahmah Atikah Rosdi ◽  
Nur Izzati Mohd Anuar
Keyword(s):  
Particle Size ◽  
Rice Husk ◽  
Sol Gel ◽  
Average Particle Size ◽  
Average Particle ◽  
Silica Source ◽  
Transmission Electron ◽  
Particle Size Analyzer ◽  
Bimetallic Materials ◽  
Co Nanoparticles

A series of Fe-Co nanoparticles were synthesized via sol-gel route at acidic, neutral and basic condition using rice husk as the silica source. The synthesized nanomaterials were designated as Fe-Co3, Fe-Co7 and Fe-Co9 and characterized by Fourier Transform Infrared (FTIR), Transmission Electron Microscope (TEM) and particle size analyzer. The great effect of pH was clearly evidenced from the shifting in the siloxane bond in the FTIR spectrum. TEM investigation confirmed the existence of discrete and almost sphere like nanoparticles. The particle size decreased with an increase in the pH, registering the smallest average particle size at pH 9. In brief, this study promises a fast, rapid and promising method for the conversion of silica rice husk into nanoscale bimetallic materials.

Molten Salt Synthesis of CaCu3Ti4O12

2008 ◽  
Vol 368-372 ◽  
pp. 115-117 ◽  
Author(s):  
Ke Pi Chen ◽  
Yong He ◽  
Dong Yu Liu ◽  
Zong De Liu
Keyword(s):  
Particle Size ◽  
Molten Salt ◽  
Average Particle Size ◽  
Particle Morphology ◽  
Holding Time ◽  
Molten Salt Synthesis ◽  
Average Particle ◽  
Molten Salt Method ◽  
Particle Size Analyzer ◽  
Size And Morphology

CCTO powders were prepared by using molten salt method in the NaCl-KCl system. The effects of temperature and holding time on phase compositions, particle morphology and size have been investigated by X-ray diffraction, scanning electron microscope and laser particle size analyzer. Using CaCO3, CuO and TiO2 as starting materials, CCTO compound could be synthesized at any temperature from 800oC to 1000oC in the NaCl-KCl system. The average particle size increased obviously with the increasing of temperature above 850 oC. Holding time had great effect on grain size and morphology.

scholarly journals CHARACTERIZATION OF HYDROXYPROPYL CELLULOSE PRODUCED FROM α-CELLULOSE BETUNG BAMBOO (DENDROCALAMUS ASPER) AND IT’S APPLICATION IN TABLET FORMULATION

2019 ◽  
pp. 123-129
Author(s):  
Herman Suryadi ◽  
Harmita . ◽  
Muhammad Herpi Akbar ◽  
Pingkan Lestari ◽  
Pingkan Lestari
Keyword(s):  
Particle Size ◽  
Average Particle Size ◽  
Hydroxypropyl Cellulose ◽  
Tablet Formulation ◽  
Average Weight ◽  
Average Particle ◽  
Disintegration Time ◽  
Particle Size Analyzer ◽  
Size Uniformity ◽  
Powder Characteristics

Objective: This study aimed to obtain the physicochemical properties of hydroxypropyl cellulose (HPC) powder from α-cellulose Betung bamboo and its characteristics in tablet formulation. Methods: HPC was prepared by hydroxypropylation of α-cellulose using 25% (w/v) sodium hydroxide and 10 ml propylene oxide (based on 1 g α-cellulose) at 70 °C for 3 h. HPC of Betung bamboo (HPC BB) was characterized using fourier transform infrared (FTIR) spectrometry, particle size analyzer (PSA), x-ray diffraction (XRD), scanning electron microscope (SEM) and compared to HPC grade SL (HPC SL) as the reference. Then, HPC BB was used as a binder in tablet formulation by direct compression method and the resulted tablets were evaluated. The tablets evaluation including weight and size uniformity, hardness, friability and disintegration time. Results: The results showed HPC BB powder was yellowish white, odorless and tasteless, pH 7.49, residue on ignition 0.68%, hydroxypropoxy groups content 54.75%, average particle size 37.39 μm, loss on drying 1.09%, and moisture content 3.34%. Flow properties of powder fulfilled the requirements based on literature. Infrared spectrum and diffraction pattern of HPC BB were relatively similar to HPC SL. The tablets have average weight 403.495 mg, diameter 12.16 mm, thickness 3.11 mm, hardness 4.11 KPa, friability 2.04% and disintegration time 24.88 s. Conclusion: Based on the comparison of powder characteristics and tablets evaluation, HPC BB has a great potential in tablet formulation which showed similar characteristics to reference.

Differential Photosensor Activities for the L-Cysteine and L-Serine Capped ZnS:Mn Nanocrystals in the Detection of Divalent Transition Metal Ions in Aqueous Solution

2020 ◽  
Vol 20 (11) ◽  
pp. 6723-6731
Author(s):  
Mi Choi ◽  
Cheong-Soo Hwang
Keyword(s):  
Aqueous Solution ◽  
Particle Size ◽  
Transition Metal ◽  
Metal Ions ◽  
Average Particle Size ◽  
Transition Metal Ions ◽  
Average Particle ◽  
Quenching Effect ◽  
Transmission Electron ◽  
Particle Size Analyzer

Colloidal ZnS:Mn nanocrystals (NCs) were synthesized in water by capping the NC surface with conventional amino acids: L-cysteine (Cys) and L-serine (Ser) molecules, which have very similar structures but different terminal functional groups. The optical properties were investigated by using UV-Visible and photoluminescence (PL) spectroscopy. The PL spectra for both ZnS:Mn-Cys and ZnS:Mn-Ser NCs showed broad emission peaks at 590 nm. The measured average particle size from the high-resolution transmission electron microscopy (HR-TEM) images were 4.38 nm (ZnS:Mn-Cys) and 5.57 nm (ZnS:Mn-Ser), which were also supported by Debye-Scherrer calculations. In addition, the surface charge of the NCs in aqueous solutions were measured using zeta-particle size analyzer spectroscopy, which showed formation of negatively charged surface for the ZnS:Mn-Cys (−43.93 mV) and ZnS:Mn-Ser (−8.21 mV) NCs in water. In this present study those negatively charged NCs were applied as photosensors for the detection of specific divalent transition metal cations in aqueous solution at the same condition. Consequently, the ZnS:Mn-Cys and ZnS:Mn-Ser NCs showed totally different photosensor activities upon the addition of first-row divalent transition metal ions. The former NCs showed luminescence quenching for most added metal ions except for Zn (II) ions; whereas the latter NCs showed exclusive quenching effect for Cu (II) ions at the same conditions. These results suggested that those NCs can be applied as Zn2+ and Cu2+ ion sensors in water.

Effect of Grinding Methods on the Performance of Ground Fly Ash

2011 ◽  
Vol 477 ◽  
pp. 10-15
Author(s):  
Zhong Yuan Lu ◽  
Xun Xu ◽  
Jun Li
Keyword(s):  
Particle Size ◽  
Fly Ash ◽  
Ball Mill ◽  
Average Particle Size ◽  
Average Particle ◽  
Uniformity Coefficient ◽  
Mortar Strength ◽  
Particle Size Analyzer ◽  
Vibration Mill ◽  
Scanning Electron

In this study, coarse fly ash was ground with laboratory ball mill, vibration mill and jet mill respectively. The powder characteristic of ground fly ash was tested by laser particle size analyzer and scanning electron microscope. And the performance of cement containing different ground fly ash was also studied. It was observed that the characteristic value of fly ash ground by ball mill, vibration mill and jet mill was 13.543 μm, 13.403 μm and 17.344 μm, respectively, when average particle size was about 25μm. And the uniformity coefficient of fly ash ground by ball mill, vibration mill, and jet mill was 1.26, 1.24 and 1.38, respectively. Specially, the mortar strength was increased when 10 to 20 percent of ground fly ash was added. And the highest fluidity of mortar was obtained when 30 percent of fly ash ground by jet mill was added.

scholarly journals β-hexanitrohexaazaisowurtzitane Particles Prepared by Spray Drying and its Characterization

2021 ◽  
Vol 27 (1) ◽  
pp. 119-124
Author(s):  
Wenzheng XU ◽  
Hao LI ◽  
Xin LIANG ◽  
Jie WANG ◽  
Jinyu PENG ◽  
...  
Keyword(s):  
Particle Size ◽  
Spray Drying ◽  
Ultrafine Particles ◽  
Average Particle Size ◽  
Narrow Particle Size Distribution ◽  
Average Particle ◽  
Thermal Stimulus ◽  
Particle Size Analyzer ◽  
Xrd Patterns ◽  
The Impact

In this paper, the ultrafine β-hexanitrohexaazaisowurtzitane (β – CL – 20) particles were prepared by spray drying method. The CL – 20 samples were characterized by scanning electron microscope (SEM), particle size analyzer, X-ray diffraction (XRD), and Differential Scanning Calorimeter (DSC). Furthermore, the safety properties of samples under impact and thermal stimulus were tested and analyzed. The results of SEM showed that the average particle size of ultrafine CL – 20 particles with a narrow particle size distribution, were about 320 nm, and the shape was elliptical. The XRD patterns indicated that the polymorphic phase of ultrafine particles was mainly β-type. Compared with that of raw CL – 20, the impact sensitivity of the ultrafine CL – 20 had been decreased significantly, for the drop height (H50) was increased from 13.0 to 33.5 cm. The critical explosion temperature of the ultrafine CL – 20 decreased from 232.16 ℃ to 227.93 ℃, indicating that the thermal stability of the ultrafine CL – 20 is lower than that of raw CL – 20.

Study on Environment-Friendly Epoxy Emulsion Modified by Two Silane Coupling Agents

2011 ◽  
Vol 347-353 ◽  
pp. 858-861 ◽  
Author(s):  
Wen Lu Guo ◽  
Han Qing Lu ◽  
Hong Chun Zhou ◽  
Wei Hu
Keyword(s):  
Particle Size ◽  
Average Particle Size ◽  
Coupling Agents ◽  
Average Particle ◽  
Nano Particle ◽  
Silane Coupling Agents ◽  
Environment Friendly ◽  
Particle Size Analyzer ◽  
Silane Coupling ◽  
Epoxy Emulsion

The environment-friendly epoxy emulsion was synthesized by MAA, BA, St reacting as grafting monomer, while silane coupling agents played a role as functional monomer. Experimental results were characterized by Nano-particle size analyzer, EIS, UV-VIS spectrophotometer, FTIR and TGA. The results of Nano-particle size analyzer showed the average particle size lower than 300nm and emulsion had lowest water absorption when ω(KH560+KH550) was 7%. The results of EIS and UV-VIS spectrum showed the cured firm had the best corrosion resistance and weather resistance while n(KH560):n(KH550)=2:1. The results of FTIR showed the silane coupling agents had successfully grafted in the skeletal structure of epoxy molecules. The results of TGA showed the thermal stability were better than unmodified.

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