Preparation of Cerium Dioxide Film by Anodization in Na2C2O4-NH3∙H2O-H2O-(CH2OH)2 Electrolyte

2017 ◽  
Vol 748 ◽  
pp. 7-11
Author(s):  
Xiao Zhen Liu ◽  
Wei Ren Rong ◽  
Xiao Zhou Liu ◽  
Xiao Hui Ren ◽  
Jie Chen ◽  
...  
Keyword(s):  
Oxide Film ◽  
Ethylene Glycol ◽  
Cerium Oxide ◽  
Cerium Dioxide ◽  
Raw Materials ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heat Treated ◽  
Scanning Electron Microcopy ◽  
Dioxide Film

The cerium dioxide films were prepared with cerium foils as raw materials by anodization in Na2C2O4-NH3∙H2O-H2O-(CH2OH)2 electrolyte. The anodic cerium oxide film was heat treated at 550°C. The cerium dioxide films were characterized with X-ray diffraction (XRD), energy-dispersive analyses of X-ray (EDAX), Fourier transform infrared (FTIR) techniques and scanning electron microcopy (SEM), respectively. The anodic cerium oxide film is semi crystalline film. The heat treated anodic cerium oxide film at 550°C is the fluorite-structured cerium dioxide film, and the crystal structure of the cerium dioxide film becomes more complete than that of the anodic cerium oxide film. The cerium dioxide film is porous film. The water, ethylene glycol and CO2 are adsorbed in the anodic cerium oxide film. The adsorbing water, ethylene glycol and CO2 in the anodic cerium oxide film are removed at 550°C. The cerium dioxide film has strong absorption in the range of 1400~4000cm-1.

Effect of Heat Treatment on the Crystal Structure of the Anodic Cerium Oxide Films

2017 ◽  
Vol 748 ◽  
pp. 12-16
Author(s):  
Xiao Zhen Liu ◽  
Yu Fan Ni ◽  
Xiao Zhou Liu ◽  
Le Tian Xia ◽  
Jie Chen ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Oxide Film ◽  
Crystal Structures ◽  
Cerium Oxide ◽  
Cerium Dioxide ◽  
Raw Materials ◽  
Oxide Films ◽  
Treatment Temperature ◽  
Heat Treated ◽  
Dioxide Film

The cerium dioxide films were prepared with cerium foils as raw materials by anodization in Na2C2O4-NH3∙H2O-H2O-(CH2OH)2 electrolyte. The anodic cerium oxide films were heat treated in 100~400°C and 0.5~2.5h, respectively. The heat treated anodic cerium oxide films were characterized with X-ray diffraction (XRD). The heat treated anodic cerium oxide film at 100°C is semi crystalline film. The heat treated anodic cerium oxide film at 200°C, 300°C, 350°C, 400°C, respectively for 2h, is the cerium dioxide film respectively, and has a structure of cubic fluorite respectively. The crystal structures of the cerium dioxide films become more complete with the increase of heat treatment temperature in 200 ~ 400 °C. The heat treated anodic cerium oxide film at 400°C for 0.5h, 1h, 1.5h, 2.5h, respectively, is the cerium dioxide film respectively, and has a structure of cubic fluorite respectively. The crystal structures of the cerium dioxide films become more complete with the increase of heat treatment times in 0.5h ~ 2.5h.

Formation of TiC-Reinforced Iron Based Composite through Carbothermal Reduction of Hematite and Anatase

2010 ◽  
Vol 173 ◽  
pp. 116-121
Author(s):  
Mohd Salihin Hassin ◽  
Zuhailawati Hussain ◽  
Palaniandy Samayamutthirian
Keyword(s):  
Carbothermal Reduction ◽  
Milling Time ◽  
Constant Pressure ◽  
Raw Materials ◽  
Anatase Tio2 ◽  
Vacuum Furnace ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heat Treated ◽  
Hematite Fe2o3

In this research carbothermal reduction of mechanical activated hematite (Fe2O3), anatase (TiO2) and graphite (C) mixture was investigated. Mixture of raw materials with composition of Fe-20vol%TiC was mechanically activated in a planetary ball mill with different milling time (0h-60h) in argon atmosphere. X-ray diffraction (XRD) results showed the intensity of Fe2O3 reduced with milling time. The activated powders were pressed using cold pressing under a constant pressure (100MPa) and heat treated at 1100°C for sintering in a vacuum furnace. The increase in milling time resulted in the formation of iron (Fe) and titanium carbide (TiC) phase as confirmed by XRD result.

Synthesis and Characterization of α-Phase Silicon Nitride Powders by Direct Nitridation

2013 ◽  
Vol 631-632 ◽  
pp. 434-436
Author(s):  
Jiu Ming Liu ◽  
Jian Lei Wang ◽  
Shu Xia Ren
Keyword(s):  
Silicon Nitride ◽  
Raw Materials ◽  
X Ray Diffraction ◽  
Nitrogen Gas ◽  
Pure Nitrogen ◽  
X Ray ◽  
Α Phase ◽  
Heat Treated ◽  
Direct Nitridation

Using silicon powders as raw materials, adding nano-silicon nitride as a diluent and NH4Cl3 and FeCl3 as catalysts, α-phase silicon nitride powders were prepared by direct nitridation method. The silicon powders were first milled with 20% α-Si3N4 and 4% NH4Cl3 for 30 minutes. Then the mixture was heat-treated at 1300°C for 1 hour in the pure nitrogen gas. The phases and their content of the as-prepared product were detected by X-ray diffraction (XRD) and the microstructure was studied by scanning electron microscope (SEM). The results showed that the product mainly consisted ofα-Si3N4 with a mass fraction over 92% and were submicron-sized particles．

Synthesis of Ba2B5O9Cl Whiskers via Flux Method

2012 ◽  
Vol 535-537 ◽  
pp. 2567-2570
Author(s):  
Dong Hai Zhu ◽  
Xue Ying Nai ◽  
Qian Qian Song ◽  
Shan Yun ◽  
Yong Xing Zhang ◽  
...  
Keyword(s):  
Sintering Temperature ◽  
Raw Materials ◽  
Mass Ratio ◽  
Optimum Conditions ◽  
X Ray Diffraction ◽  
Flux Method ◽  
High Quality ◽  
X Ray ◽  
Scanning Electron Microcopy ◽  
Scanning Electron

Ba2B5O9Cl whiskers with uniform morphology were synthesized by a simple flux method, using BaCl2•2H2O, H3BO3 as the starting materials, and KCl as the flux. The products were characterized by X-ray diffraction (XRD) and scanning electron microcopy (SEM), and the optimum conditions for preparing high quality Ba2B5O9Cl whiskers were studied. Results show that a sintering temperature around 700 °C, an Ba/B mole ratio of 1:3 and a raw materials to flux mass ratio of 1:2 lead to uniform orthorhombic Ba2B5O9Cl whiskers with a diameter of 0.4-1.0 µm and a length of 10-25 µm.

Precipitation of Hydroxyapatite on Oxide Film Containing Ca and P by Hydrothermal Treatment

2007 ◽  
Vol 280-283 ◽  
pp. 1537-1540
Author(s):  
Fu Liu ◽  
Fu Ping Wang ◽  
Tadao Shimizu ◽  
K. Igarashi ◽  
Lian Cheng Zhao
Keyword(s):  
Oxide Film ◽  
Hydrothermal Treatment ◽  
Oxide Films ◽  
Microarc Oxidation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electron Probe Micro Analyzer ◽  
Scanning Electron Microcopy ◽  
Before And After ◽  
Hydroxyapatite Crystals

An oxide film containing Ca and P was obtained in an electrolyte containing calcium glycerphosphate (Ca-GP) and calcium acetate (CA) by microarc oxidation. The surfaces of the oxide films were porous and rough, and the Ca/P ratio in the oxide film was 1.71 when the oxide film was formed in the electrolyte containing 0.06 M Ca-GP and 0.25 M CA at current density 50 A/m2 and final voltage 350 V. The oxide film with Ca/P ration 1.71 was treated hydrothermally at 190°C for 10 hours in an autoclave. It was found that hydroxyapatite crystals were precipitated on the oxide film after hydrothermal treatment. The oxide films were investigated by means of electron probe micro analyzer, X-ray diffraction, scanning electron microcopy before and after hydrothermal treatment.

scholarly journals Waste and Solar Energy: An Eco-Friendly Way for Glass Melting

2021 ◽  
Vol 5 (2) ◽  
pp. 16
Author(s):  
Isabel Padilla ◽  
Maximina Romero ◽  
José I. Robla ◽  
Aurora López-Delgado
Keyword(s):  
Solar Energy ◽  
Environmental Sustainability ◽  
Raw Materials ◽  
Glass Melting ◽  
Glass Network ◽  
X Ray Diffraction ◽  
X Ray ◽  
Concentrated Solar Energy ◽  
Calcium Source ◽  
The Aluminum Industry

In this work, concentrated solar energy (CSE) was applied to an energy-intensive process such as the vitrification of waste with the aim of manufacturing glasses. Different types of waste were used as raw materials: a hazardous waste from the aluminum industry as aluminum source; two residues from the food industry (eggshell and mussel shell) and dolomite ore as calcium source; quartz sand was also employed as glass network former. The use of CSE allowed obtaining glasses in the SiO2-Al2O3-CaO system at exposure time as short as 15 min. The raw materials, their mixtures, and the resulting glasses were characterized by means of X-ray fluorescence, X-ray diffraction, and differential thermal analysis. The feasibility of combining a renewable energy, as solar energy and different waste for the manufacture of glasses, would highly contribute to circular economy and environmental sustainability.

scholarly journals Stable and Metastable Phase Equilibria Involving the Cu6Sn5 Intermetallic

2021 ◽  
Author(s):  
A. Leineweber ◽  
M. Löffler ◽  
S. Martin
Keyword(s):  
Phase Equilibria ◽  
Electron Backscatter Diffraction ◽  
Metastable Phase ◽  
Stable Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heat Treated ◽  
Ordered Phases ◽  
Backscatter Diffraction ◽  
Kinetics Of

Abstract Cu6Sn5 intermetallic occurs in the form of differently ordered phases η, η′ and η′′. In solder joints, this intermetallic can undergo changes in composition and the state of order without or while interacting with excess Cu and excess Sn in the system, potentially giving rise to detrimental changes in the mechanical properties of the solder. In order to study such processes in fundamental detail and to get more detailed information about the metastable and stable phase equilibria, model alloys consisting of Cu3Sn + Cu6Sn5 as well as Cu6Sn5 + Sn-rich melt were heat treated. Powder x-ray diffraction and scanning electron microscopy supplemented by electron backscatter diffraction were used to investigate the structural and microstructural changes. It was shown that Sn-poor η can increase its Sn content by Cu3Sn precipitation at grain boundaries or by uptake of Sn from the Sn-rich melt. From the kinetics of the former process at 513 K and the grain size of the η phase, we obtained an interdiffusion coefficient in η of (3 ± 1) × 10−16 m2 s−1. Comparison of this value with literature data implies that this value reflects pure volume (inter)diffusion, while Cu6Sn5 growth at low temperature is typically strongly influenced by grain-boundary diffusion. These investigations also confirm that η′′ forming below a composition-dependent transus temperature gradually enriches in Sn content, confirming that Sn-poor η′′ is metastable against decomposition into Cu3Sn and more Sn-rich η or (at lower temperatures) η′. Graphic Abstract

scholarly journals Mining Wastes of an Albite Deposit as Raw Materials for Vitrified Mullite Ceramics

Minerals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 232
Author(s):  
Pedro J. Sánchez-Soto ◽  
Eduardo Garzón ◽  
Luis Pérez-Villarejo ◽  
George N. Angelopoulos ◽  
Dolores Eliche-Quesada
Keyword(s):  
Particle Size ◽  
Raw Materials ◽  
Phase Evolution ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Mining Wastes ◽  
X Ray Diffraction ◽  
X Ray ◽  
Maximum Value

In this work, an examination of mining wastes of an albite deposit in south Spain was carried out using X-ray Fluorescence (XRF), X-ray diffraction (XRD), particle size analysis, thermo-dilatometry and Differential Thermal Analysis (DTA) and Thermogravimetric (TG) analysis, followed by the determination of the main ceramic properties. The albite content in two selected samples was high (65–40 wt. %), accompanied by quartz (25–40 wt. %) and other minor minerals identified by XRD, mainly kaolinite, in agreement with the high content of silica and alumina determined by XRF. The content of Na2O was in the range 5.44–3.09 wt. %, being associated with albite. The iron content was very low (<0.75 wt. %). The kaolinite content in the waste was estimated from ~8 to 32 wt. %. The particle size analysis indicated values of 11–31 wt. % of particles <63 µm. The ceramic properties of fired samples (1000–1350 °C) showed progressive shrinkage by the thermal effect, with water absorption and open porosity almost at zero at 1200–1250 °C. At 1200 °C, the bulk density reached a maximum value of 2.38 g/cm3. An abrupt change in the phase evolution by XRD was found from 1150 to 1200 °C, with the disappearance of albite by melting in accordance with the predictions of the phase diagram SiO2-Al2O3-Na2O and the system albite-quartz. These fired materials contained as main crystalline phases quartz and mullite. Quartz was present in the raw samples and mullite was formed by decomposition of kaolinite. The observation of mullite forming needle-shape crystals was revealed by Scanning Electron Microscopy (SEM). The formation of fully densified and vitrified mullite materials by firing treatments was demonstrated.

The Relative Merits of Oxides of Hafnium, Cerium and Thorium as Surrogates for Plutonium Oxide in Calcium Phosphate Ceramics

2009 ◽  
Vol 1193 ◽  
Author(s):  
B. L. Metcalfe ◽  
S. K. Fong ◽  
L. A. Gerrard ◽  
I. W. Donald ◽  
E. S. Welch ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Calcination Temperature ◽  
Cerium Oxide ◽  
Absorption Spectroscopy ◽  
Hafnium Oxide ◽  
Intermediate Level ◽  
X Ray Diffraction ◽  
X Ray ◽  
X Ray Absorption ◽  
Additional Phase

AbstractThe choice of surrogate for plutonium oxide for use during the initial stages of research into the immobilization of intermediate level pyrochemical wastes containing plutonium andamericium oxides in a calcium phosphate host has been investigated by powder X-ray diffraction and X-ray absorption spectroscopy. Two non-radioactive surrogates, hafnium oxide and cerium oxide, together with radioactive thorium oxide were compared. Similarities in behaviour were observed for all three surrogates when calcined at the lowest temperature, 750°C but differences became more pronounced as the calcination temperature was increased to 950°C. Although some reaction occurred between all the surrogates and the host to form a substituted whitlockite phase, increasing the temperature led to a significant increase in the cerium reaction and the formation of an additional phase, monazite. Additionally it was observed that the cerium became increasingly trivalent at higher temperatures.

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