Preparation of Dispersed Y2O3-MgO Nanopowder from Stearate

2018 ◽  
Vol 279 ◽  
pp. 208-213
Author(s):  
Hua Dong Wang ◽  
Zhi Qiang Sun ◽  
Xiao Bo Yang ◽  
Tao Wu ◽  
Heng Dong ◽  
...  
Keyword(s):  
Particle Size ◽  
Hydrogen Bonds ◽  
Calcination Temperature ◽  
Formation Mechanism ◽  
Potential Application ◽  
Average Particle Size ◽  
Ceramic Materials ◽  
Average Particle ◽  
Water Medium ◽  
Ft Ir

Dispersed Y2O3-MgO nanopowder was synthesized by calcining the stearate. XRD, TG-DTA, FT-IR, BET and FE-SEM were employed to analyze The formation mechanism of the precursor and the Y2O3-MgO nanopowder. Pure and dispersed Y2O3-MgO nanopowder with an average particle size of 40 nm was produced by calcining the precursor at 600 °C. The particle size increases to about 70 nm with the increase of the calcination temperature to 700 °C. In the preparation of Y2O3-MgO from stearate, no water medium is involved, thus capillarity force and bridging of adjacent particles by hydrogen bonds can be avoided, resulting in good dispersion of the particles. The dispersed Y2O3-MgO nanopowder prepared in this work has potential application in infrared transparent ceramic materials.

Synthesis of Dispersed Y2O3 Nanopowder from Yttrium Stearate

2013 ◽  
Vol 544 ◽  
pp. 3-7 ◽  
Author(s):  
Jin Sheng Li ◽  
Xu Dong Sun ◽  
Shao Hong Liu ◽  
Di Huo ◽  
Xiao Dong Li ◽  
...  
Keyword(s):  
Particle Size ◽  
Raw Materials ◽  
Average Particle Size ◽  
Ceramic Materials ◽  
Average Particle ◽  
Water Medium ◽  
Nitrate Hexahydrate ◽  
Yttrium Nitrate ◽  
Ft Ir ◽  
Yttrium Nitrate Hexahydrate

Fine yttrium stearate powder was produced at a relatively low temperature using yttrium nitrate hexahydrate, ammonia and stearic acid as the raw materials. Dispersed Y2O3 nanopowder was synthesized by calcining the yttrium stearate. The formation mechanism of the precursor and the Y2O3 nanopowder was studied by means of XRD, TG-DTA, FT-IR, BET, FE-SEM and HR-TEM. Pure and dispersed Y2O3 nanopowder with an average particle size of 30 nm was produced by calcining the precursor at 600 °C. The particle size increases to about 60 nm with the increase of the calcination temperature to 1000 °C. In the preparation of Y2O3 from yttrium stearate, no water medium is involved, thus capillarity force and bridging of adjacent particles by hydrogen bonds can be avoided, resulting in good dispersion of the particles. The dispersed Y2O3 nanopowder prepared in this work has potential application in phosphors and transparent ceramic materials.

Fabrication and Characterization of Nanospinel ZnCr2O4 Using Thermal Treatement Method

2015 ◽  
Vol 1107 ◽  
pp. 301-307 ◽  
Author(s):  
Salahudeen A. Gene ◽  
Elias B. Saion ◽  
Abdul Halim Shaari ◽  
Mazliana A. Kamarudeen ◽  
Naif Mohammed Al-Hada
Keyword(s):  
Particle Size ◽  
Calcination Temperature ◽  
Average Particle Size ◽  
Treatment Method ◽  
Esr Spectra ◽  
Resonance Spectroscopy ◽  
Average Particle ◽  
Face Centered Cubic ◽  
X Ray ◽  
Xrd Patterns

The fabrication of nanospinel zinc chromite (ZnCr2O4) crystals by the means of thermal treatment method from an aqueous solution containing metal nitrates, polyvinyl pyrrolidone (PVP), and deionized water was described in this study. The samples were calcined at various temperatures ranging from 773 to 973 K for the decomposition of the organic compounds and crystallization of the nanocrystals. PVP was used as capping agent to control the agglomeration of the particles. The characterization studies of the fabricated samples were carried out by X-ray diffraction spectroscopy (XRD), transmission electron microscopy (TEM), energy dispersed X-ray spectroscopy (EDX) and electron spin resonance spectroscopy (ESR). The corresponding peaks of Zn, Cr and O were observed in the EDX spectrum of the sample which confirms the formation of ZnCr2O4. The XRD patterns also confirmed the formation of the single faced nanocrystallines of spinel ZnCr2O4 with a face-centered cubic structure. The average particle size of the synthesized crystals was also determined from the XRD patterns using the Scherers formula which shows that the crystallite sizes increases with increase in calcination temperature and was in good agreement with the TEM images which shows cubical ZnCr2O4 nanocrystals with uniform morphology and particle size distributions. The ESR spectra confirmed the existence of unpaired electron in the fabricated samples and the increase in g-factor and decreases in resonant magnetic field (Hr) were observed as the calcination temperature increases.

Rheological, Structural and Mechanical Characterization of Monolithic Zircon-Alumina Bodies

2014 ◽  
Vol 793 ◽  
pp. 151-158 ◽  
Author(s):  
M. León-Carriedo ◽  
C.A. Gutiérrez Chavarría ◽  
J.L. Rodríguez Galicia ◽  
Jorge López-Cuevas ◽  
M.I. Pech Canul
Keyword(s):  
Particle Size ◽  
Raw Materials ◽  
Mechanical Test ◽  
Average Particle Size ◽  
Young Modulus ◽  
Particle Morphology ◽  
Ceramic Materials ◽  
Transgranular Fracture ◽  
Average Particle

In the present work, the characterization of monolithic materials formulated at different weight concentrations was conducted; employing two of the ceramic materials most used in the refractory industry, zircon and alumina. These monolithic materials were fabricated using colloidal techniques, specifically plaster casting mold, in order to obtain pieces with a higher particle consolidation and density, reducing porosity to lower values than the obtained using traditional shaping process of these materials. The monoliths were obtained employing two ceramic powders with different average particle size and morphology to achieve better packing in the green body. This characterization was carried out, firstly, determining the particle size of the raw materials by laser diffraction and the evaluation of particle morphology by scanning electron microscopy. Aqueous suspensions were formulated by containing both ceramic materials, which were dispersed with Tamol 963, and analyzed by rheometric techniques. Subsequently, bars were manufactured having the following dimensions; 4 mm wide, 3 mm thick and 45 mm in length, according to ASTM C1161-02cc, to be characterized microstructural and mechanically, also was observed the fracture habit after the mechanical test. As a final result, the materials formulated at higher alumina content showed higher density values, reaching 94.95% of the theoretical density, also showed a higher thermal expansion coefficient and high rupture modulus, reaching up to 600 MPa and Young modulus of 230 GPa. From the microstructure characterization it was observed that alumina matrix shows a transgranular fracture across the grains and zircon particles exhibited intergranular fracture among the grain boundaries.

Nanocrystalline BaTiO3 from freeze-dried nitrate solutions

1996 ◽  
Vol 11 (5) ◽  
pp. 1199-1209 ◽  
Author(s):  
J. M. McHale ◽  
P. C. McIntyre ◽  
K. E. Sickafus ◽  
N. V. Coppa
Keyword(s):  
Particle Size ◽  
Calcination Temperature ◽  
High Surface ◽  
Nitrate Solution ◽  
Average Particle Size ◽  
Volume Ratio ◽  
Product Formation ◽  
Cubic Phase ◽  
Average Particle ◽  
Freeze Dried

An aqueous, all nitrate, solution-based preparation of BaTiO3 is reported here. Rapid freezing of a barium and titanyl nitrate solution, followed by low temperature sublimitation of the solvent, yielded a freeze-dried nitrate precursor which was thermally processed to produce BaTiO3. XRD revealed that 10 min at temperatures ≧600 °C resulted in the formation of phase pure nanocrystalline BaTiO3. TEM revealed that the material was uniform and nanocrystalline (10–15 nm). The high surface to volume ratio inherent in these small particles stabilized the cubic phase of BaTiO3 at room temperature. It was also found that the average particle size of the BaTiO3 produced was highly dependent upon calcination temperature and only slightly dependent upon annealing time. This result suggests a means of selection of particle size of the product through judicious choice of calcination temperature. The experimental details of the freeze-dried precursor preparation, thermal processing of the precursor, product formation, and product morphology are discussed.

scholarly journals The sintering of the ceramic materials based on the North-Onega bauxitized clay. Part 1. The granular composition effect

2018 ◽  
pp. 24-28 ◽  
Author(s):  
I. D. Kashcheev ◽  
K. G. Zemlyanoi ◽  
I. A. Pavlova
Keyword(s):  
Particle Size ◽  
Average Particle Size ◽  
Ceramic Materials ◽  
Sintering Behavior ◽  
Average Particle ◽  
Composition Effect ◽  
Granular Composition ◽  
The North

The alumina-silicate material's granular composition effect on its sintering behavior was investigated in the article. It was shown that the average particle size decreasing, the chemical and material compositions being equal, allowed to prepare stronger materials.Ill.2. Ref. 6. Tab. 4.

Preparation and Characterization of Fluorinated Epoxy Resin Emulsion for Waterborne Coatings

2011 ◽  
Vol 347-353 ◽  
pp. 4065-4068
Author(s):  
Wen Lu Guo ◽  
Hong Chun Zhou ◽  
Han Qing Lu ◽  
Wei Hu
Keyword(s):  
Contact Angle ◽  
Particle Size ◽  
Epoxy Resin ◽  
Average Particle Size ◽  
Average Particle ◽  
Waterborne Coatings ◽  
Orthogonal Experiments ◽  
Ft Ir ◽  
Emulsion Particle ◽  
Different Content

Under the action of initiator(BPO), the α-methyl acrylic acid (α-MAA), butyl hexafluorobutyl methacrylate (HFMA) and other monomers are graft copolymerized into epoxy molecular. By adding N, N-dimethyl ethanolamine, fluorine-containing water-based epoxy resin emulsion can be prepared. By orthogonal experiments, the amount of acrylic monomer, BPO dosage, grafting temperature and other optimum conditions can be determined. Infrared spectroscopy (FT-IR) characterization confirms acrylic monomers successfully grafted to the epoxy resin molecules. The study focuses on the effect of different content of HFMA on modified emulsion particle size and contact angle of coating. The results shows that the introduction of HFMA monomer made the smallest average particle size of emulsion low to 165 nm, and the contact angle against water is increased by 20°. After determining the conventional and environmental performance of the emulsion, the results shows that this preparation of epoxy resin emulsion can fully meet the requirements of waterborne coatings.

Preparation of ZnO Nanosol Dispersed in Aqueous Medium and its Dispersion Characteristics

2013 ◽  
Vol 481 ◽  
pp. 66-71 ◽  
Author(s):  
Hyeon Ha Lim ◽  
Seung Ho Lee ◽  
Hyung Mi Lim ◽  
Dae Sung Kim
Keyword(s):  
Particle Size ◽  
Zeta Potential ◽  
Aqueous Medium ◽  
Average Particle Size ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Average Particle ◽  
Dispersion Parameters ◽  
Ft Ir ◽  
Zno Powder

Highly dispersed ZnO nanosol, having an average particle size of about 40nm based on Particle Size Analysis (PSA), was prepared under aqueous solution without the removal of large particles by centrifugation. The ZnO nanosol was investigated on the effect of various dispersion parameters, i.e. milling time, dispersant content, pH, etc. The nanosol was effectively dispersed at 20~30 wt% of dispersant amount compared to ZnO content under ball-milling for 10 hours at pH 10. The dispersion characteristic of the nanosol was investigated into particle size and zeta potential. We discussed on the dispersion behavior of (-) charged ZnO particle surrounded by dispersant together with the variation of (-) charged dispersant's amount in aqueous medium at pH 10. The ZnO powder and nanosol were characterized by SEM, TEM, TGA, FT-IR, PSA and Zeta-potential.

scholarly journals Studying the Crystal Structure, Topography, and Anti-bacterial of a Novel Titania (TiO2 NPs) Prepared by a Sol-gel Manner

2019 ◽  
Vol 16 (4) ◽  
pp. 0910
Author(s):  
Fayyadh Et al.
Keyword(s):  
Particle Size ◽  
Antibacterial Activity ◽  
Titanium Dioxide ◽  
Calcination Temperature ◽  
Sol Gel ◽  
Average Particle Size ◽  
Average Particle ◽  
Gram Negative ◽  
Tio2 Nps ◽  
Average Grain Size

In this research, titanium dioxide nanoparticles (TiO2 NPs) were prepared through the sol-gel process at an acidic medium (pH3).TiO2 nanoparticles were prepared from titanium trichloride (TiCl3) as a precursor with Ammonium hydroxide (NH4OH) with 1:3 ratio at 50 °C. The resulting gel was dried at 70 °C to obtain the Nanocrystalline powder. The powder from the drying process was treated thermally at temperatures 500 °C and 700 °C. The crystalline structure, surface morphology, and particle size were studied by using X-ray diffraction (XRD), Atomic Force Microscopy (AFM), and Scanning Electron Microscope (SEM). The results showed (anatase) phase of titanium dioxide with the average grain size of 110 nm at 500 °C calcination temperature, and (anatase- rutile) mixed phase of titanium dioxide with the average particle size of 118.1 nm at 700 °C calcination temperature. The anti-bacterial activity of the synthesis specimens was recorded through the Kirby-Bauer disc method (disc devotion method). The results displayed a pretty excellent antibacterial activity of TiO2 NPs to bacteria strains: Gram positive staphylococcus aureus, gram negative pseudomonas aeruginosa, and "gram negative escherichia coli. The sensitivity of the tested bacteria to TiO2 NPs depends on the oxidation state of the TiO2 NPs, particle size, volume, and the density of the unit cell. The small- average particle size of titanium dioxide particles showed high antibacterial activity against bacteria, while the larger- average particle size of titanium dioxide particles showed less antibacterial activity. The novelty of this production is the manufacturing of a novel kind of TiO2 NPs and achievement its best antibacterial activity.

scholarly journals A Facile Synthesis of Fe3O4@SiO2@ZnO for Curcumin Delivery

2021 ◽  
Vol 12 (6) ◽  
pp. 7994-8002
Keyword(s):  
Particle Size ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Average Particle Size ◽  
Average Particle ◽  
Zno Nanoparticle ◽  
Facile Synthesis ◽  
Stöber Method ◽  
Ft Ir

This paper proposed an engineered silica-coated Fe3O4 with ZnO nanoparticle, prepared by a coprecipitation/Stöber method as a curcumin delivery system. To this end, the structural characterization of the nanocomposite was performed by Fourier transform infrared spectroscopy (FT-IR), ray diffraction (XRD), VSM, and TEM. The findings show that the synthesized nanocomposite has a semispherical structure with an average particle size of 50-70 nm and excellent magnetization properties (21.4 emu/g).

The Preparation and Characteristics of Chitosan-Acetaminophen Drug-Loading Micropheres

2012 ◽  
Vol 586 ◽  
pp. 161-165 ◽  
Author(s):  
Hao Ran Zhou ◽  
Jing Yu Zhang ◽  
Hao Jiang
Keyword(s):  
Particle Size ◽  
Sustained Release ◽  
Raw Materials ◽  
Orthogonal Experiment ◽  
Drug Loading ◽  
Average Particle Size ◽  
Average Particle ◽  
Preparation Process ◽  
Structure And Morphology ◽  
Ft Ir

CS-ACAP drug-loading microsperes are prepared with using CS and ACAP as the main raw materials by emulsification-crosslinking method. Orthogonal experiment was designed to optimize the preparation process of the CS-ACAP drug-loading microspheres. FT-IR and SEM were applied to characterize the structure and morphology of microspheres. The sustained release effect of CS-ACAP microsphere was measured by sustained release measurement. The results showed that the CS-ACAP drug-loading micropheres were successfully prepared by emulsification-crosslinking method. Obtained microspheres as a perforated sphere, the average particle size of the microspheres was 30μm and the microspheres had a uniformly particle size distribution; the drug-loaded microspheres had good sustained release effect.

Sign in / Sign up

Export Citation Format

Share Document