Densification process in undoped zinc oxide

1987 ◽  
Vol 2 (4) ◽  
pp. 478-484 ◽  
Author(s):  
K. Kobayashi ◽  
P. Dordor ◽  
J. P. Bonnet ◽  
R. Salmon ◽  
P. Hagenmuller
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Initial Density ◽  
Close Relation ◽  
Zinc Nitrate ◽  
Densification Process ◽  
Final Density ◽  
Extreme Sensitivity ◽  
Sintering Conditions ◽  
Scanning Electron

An original preparation of ZnO is described where the powder is obtained by precipitaton from zinc nitrate in aqueous solution followed by a calcination. Scanning electron microscopy reveals a close relation between the initial density and the morphology of the powder, the latter being also strongly dependent on the calcining conditions. The investigation of the densification process shows the extreme sensitivity of the final density to sintering conditions. A physical model based on the competitive influences of shrinkage and evaporation successfully describes the observed phenomena.

scholarly journals SÍNTESIS Y CARACTERIZACIÓN MORFOLÓGICA DE NANOTUBOS DE ZNO SOBRE SUBSTRATOS DE VIDRIO Y DE SNO2:F

2017 ◽  
Vol 25 (1) ◽  
pp. 35
Author(s):  
Juan Rodríguez Rodríguez ◽  
Julio Alarcón ◽  
Javier Gago
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Scanning Electron Microscopy ◽  
Zinc Nitrate ◽  
Spray Pyrolysis Method ◽  
Pyrolysis Method ◽  
Palabras Clave ◽  
Zno Nanotubes ◽  
Scanning Electron

En el presente trabajo se reporta la síntesis y caracterización morfológica de nanotubos de ZnO, fabricados a partir de semillas de óxido de zinc fabricadas por el método del rociado pirolítico. El crecimiento de los nanotubos de ZnO se llevó a cabo sumergiendo los sustratos con las semillas de ZnO en una solución acuosa de nitrato de zinc y metenamina. Las muestras fabricadas bajo diferentes condiciones se analizaron en su morfología por Microscopia Electrónica de Barrido. Palabras clave.- Fotocatálisis, ZnO, Nanotubos. ABSTRACTIn this paper the synthesis and morphologic characterization of ZnO nanotubes, made from zinc oxide seed produced by the spray pyrolysis method is reported. The growth of nanotubes of ZnO was conducted by dipping the substrate with a ZnO seed aqueous solution of zinc nitrate and methenamine. The samples manufactured under different conditions were analyzed in morphology by Scanning Electron Microscopy. Keywords.- Photocatalysis, ZnO, Nanotubes.

Study on Morphologies of Palladium Coated Foam Nickel Cathodes for Dechlorination of 2,4-Dichlorophenol

2012 ◽  
Vol 571 ◽  
pp. 97-101 ◽  
Author(s):  
Jun Jing Li ◽  
Hui Ling Liu ◽  
Zhi Wei Wang ◽  
Xiu Wen Cheng
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Composite Electrode ◽  
Potential Temperature ◽  
Nickel Electrode ◽  
Polymerization Time ◽  
Applied Potential ◽  
Polypyrrole Films ◽  
Polypyrrole Film ◽  
Scanning Electron

Electrolytically deposited palladium on polypyrrole film, which is electropolymerized using potentiostatic method, covered foam nickel electrode as a support was used as cathode for the electrocatalytic hydrodechlorination of 2, 4-dichlorophenol in aqueous solution. It is well known that the morphologies of polypyrrole films have dramatic influences on the dispersion of metals and the performance of the composite electrode. The influence of applied potential, temperature and polymerization time on the morphology of the films was studied by scanning electron microscopy (SEM). The fundamental electrocatalytic hydrodechlorination (ECH) results indicated that the electrocatalytic activity of Pd loaded polypyrrole foam nickel electrode is excellent for dechlorination of 2,4-dichlorophenol. The present study shows a promising choice of this kind of composite electrode for ECH.

Study on Alumina Ceramics for Dechlorinating Reactor Lining

2008 ◽  
Vol 368-372 ◽  
pp. 707-709
Author(s):  
Shi Gang Long ◽  
Feng Cao ◽  
Liu Heng Sun ◽  
Qing Min Meng
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Spectral Analysis ◽  
Thermal Shock ◽  
Energy Dispersive ◽  
Alumina Ceramics ◽  
Sintering Conditions ◽  
Sintering Condition ◽  
Scanning Electron

Al2O3 ceramics samples were prepared by changing the ingredient and sintering conditions. The resistance experiment of the Al2O3 ceramics to hydrochloride corrosion and thermal shock were carried out, and then identified by means of scanning electron microscopy and energy dispersive spectral analysis. The results indicated the optimal Al2O3 and sintering condition for the dechlorinating reactor.

scholarly journals Preparation, Characterization, and Photocatalytic Properties of Modified Red Mud

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Mingjie Ma ◽  
Guanyu Wang ◽  
Zhengpeng Yang ◽  
Shanxiu Huang ◽  
Weijie Guo ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Scanning Electron Microscopy ◽  
Uv Irradiation ◽  
Red Mud ◽  
Structure Property ◽  
X Ray Diffraction ◽  
X Ray ◽  
Xrf Scanning ◽  
Scanning Electron

Solid waste red mud was modified by HCl leaching. The structure property and composition of modified red mud were investigated by X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET). Under UV irradiation, methyl orange (MO) aqueous solution was photodegraded by modified red mud. The obtained results showed that the specific surface area of modified red mud was 317.14 m2/g, which was about 40 times higher than that of the normal red mud. After UV irradiation for 50 min, the removal percentage of MO reached 94.2%. The study provided a novel way for the application of red mud to the photocatalytic degradation of organic wastes.

OB-IV-1Exocrine Organs Imaged in Aqueous Solution by Atmospheric Scanning Electron Microscopy (ASEM)

Microscopy ◽  
2016 ◽  
Vol 65 (suppl 1) ◽  
pp. i17.1-i17
Author(s):  
Toshiko Yamazawa ◽  
Naotoshi Nakamura ◽  
Yoshinori Mikami ◽  
Hiroshi Sekiya ◽  
Mari Sato ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Scanning Electron Microscopy ◽  
Scanning Electron

scholarly journals Observation of tissues in open aqueous solution by atmospheric scanning electron microscopy: Applicability to intraoperative cancer diagnosis

2015 ◽  
Vol 46 (5) ◽  
pp. 1872-1882 ◽  
Author(s):  
NASSIRHADJY MEMTILY ◽  
TOMOKO OKADA ◽  
TATSUHIKO EBIHARA ◽  
MARI SATO ◽  
ATSUSHI KURABAYASHI ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Scanning Electron Microscopy ◽  
Cancer Diagnosis ◽  
Scanning Electron

Hydroxyapatite Scaffolds Produced by Hydrothermal Deposition of Monetite on Polyurethane Sponges Substrates

2011 ◽  
Vol 493-494 ◽  
pp. 820-825 ◽  
Author(s):  
Fernanda Danielle Mishima ◽  
Luis Henrique Leme Louro ◽  
Felipe Nobre Moura ◽  
Luciano Andrade Gobbo ◽  
Marcelo Henrique Prado da Silva
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Tricalcium Phosphate ◽  
Porous Scaffolds ◽  
New Bone Formation ◽  
Total Conversion ◽  
X Ray ◽  
Heat Treated ◽  
Wide Range ◽  
Scanning Electron

Hydroxyapatite scaffolds have been being produced by a wide range of processes. The optimun material to be used as bone graft has to be partially resorbable, with resorption rates similar to new bone formation ones. The samples must have porosity compatible with tissue ingrowth. Hydroxyapatite and tricalcium phosphate ceramics are good choices for designing such materials. In the present study, polymeric sponges were coated with hydroxyapatite and sintered. The method consists of coating polyurethane sponges substrates in an aqueous solution rich in phosphate (PO4)3-and calcium (Ca)2+ions. The solution is composed by 0.5M Ca(OH)2, 0.3M H3PO4and 1M CH3CHCO2HOH (lactic acid) at pH of 3.7. The sponges were immersed in a beaker with the solution and heated up to 80°C to precipitate monetite on the sponge. Continuous and adherent coatings were formed on the surface of sponges interconections. These coatings were characterised by X-ray diffractometry and the only identified phase was monetite. The substrates were converted to hydroxyapatite in an alkali solution.The total conversion from monetite to hydroxyapatite was confirmed by XRD analyses. The struts were heat treated in order to eliminate the organic sponge and sinter the scaffolds. After sintering, hydroxyapatite and tricalcium phosphate were identified on the struts. Optical microscopy revealed the morphology of the struts, while scanning electron microscopy (SEM) showed the precipitates morphology. The method showed to be efficient in the production of porous scaffolds.

Multilayer ZrO2 Precursor Coated Polystyrene Particles

2007 ◽  
Vol 280-283 ◽  
pp. 529-532
Author(s):  
Yu Jia ◽  
Yuji Hotta ◽  
Kimiyasu Sato ◽  
Koji Watari ◽  
Lennart Bergström
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Scanning Electron Microscopy ◽  
Zeta Potential ◽  
Multilayer Coating ◽  
Coating Process ◽  
Surface Charges ◽  
Coated Particles ◽  
Particles Size Distribution ◽  
Scanning Electron

Monodispersed ZrO2 (includes 8mol % Y2O3) precursor nanoparticles, which were well dispersed in aqueous solution, were successfully synthesized. The as-synthesized ZrO2 precursor nanoparticles were homogenously coated on the surface of polystyrene particles. Multilayer coating process was successfully implemented by using polyacrylic acid (PAA) to modify the surface charges of the coated particles, which was characterized by zeta-potential, particles size distribution and scanning electron microscopy (SEM).

scholarly journals Chemical and Wetting Analysis of the Ni-Ti Coating on SiC Improved by a 2-Step Coating-Sintering Process

Materials ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5235
Author(s):  
Yang Liu ◽  
Ying-Xin Wang ◽  
Qiang Yang ◽  
Fu Wang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Sintering Process ◽  
X Ray Diffraction ◽  
Control Groups ◽  
X Ray ◽  
Surface Energies ◽  
Metal Ceramic ◽  
Sintering Conditions ◽  
Scanning Electron

A two-stepped coating-sintering process to prepare the qualified Ni–Ti transition applied in metal-ceramic bonding proved to be effective to improve the wetting abilities. The method was introduced in detail and compared with 2 control groups. To analyze the benefits, the morphology and composition were captured by field emission scanning electron microscopy (FE-SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). The comparisons of different coating depths and different sintering conditions were also recorded and analyzed. The influence of the EDS detecting depth was a concern in the discussions. Finally, the contact angle tests and surface energies were also estimated to verify the reliability of the transition layer. The results indicated that the coating-sintering process combined with protective sintering was preferred and necessary to increase the activeness.

Characterization of Synthesized SnO2 Nanoparticles and its Application for the Photo Catalytic Degradation of Eosin Y in Aqueous Solution

2021 ◽  
Vol 43 (1) ◽  
pp. 14-14
Author(s):  
Fazal Akbar Jan Fazal Akbar Jan ◽  
Muhammad Aamir Muhammad Aamir ◽  
Naimat Ullah and Husaain Gulab Naimat Ullah and Husaain Gulab
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Scanning Electron Microscopy ◽  
Sno2 Nanoparticles ◽  
Catalytic Degradation ◽  
Eosin Y ◽  
X Rays ◽  
Visible Spectroscopy ◽  
Uv Visible ◽  
Scanning Electron

The synthesized oxide (SnO2) nanoparticles by sol-gel method were characterized using UV-Visible spectroscopy (UV-Vis), Fourier Transform Infrared spectroscopy (FTIR), X-rays diffraction(XRD) and Scanning electron microscopy(SEM). Using X-rays diffraction analysis different parameter were calculated such as crystallite size, d-spacing, dislocation density, number of unit cell, cell volume, morphological index, micro strain and instrumental broadening. The average particle size was 28.396 nm. Scanning electron microscopy revealed that SnO2 nanopartcles are uniformly distributed. Optical properties such as band gap (energy gap = 3.6 eV) was calculated from UV-Visible spectroscopy. The characterized particles were used as photocatalyst for the degradation of Eosin dye in aqueous solution under UV light. The effect of different parameters i.e irradiation time, initial dye concentration, pH of the medium and catalyst weight on percent degradation was also studied. Mmaximum dye degradation was found at 220 minutes time interval that was 92 % using 10 ppm solution. At pH 5 the degradation of dye was found to be 94%. The catalyst dose of 0.06 g was found to be the optimum weight for the best photo catalytic degradation of Eosin Y.

Sign in / Sign up

Export Citation Format

Share Document