Measurement of the Crystallinity of Hydroxyapatite Deposited by Plasma Spray

1997 ◽  
Author(s):  
F. Rustichelli ◽  
B. Yang ◽  
N. Antolotti ◽  
S. Bertini ◽  
E. Girardin
Keyword(s):  
Plasma Spray ◽  
Powder Mixture ◽  
Hip Prosthesis ◽  
Normalization Method ◽  
X Ray Diffraction ◽  
Crystalline Powder ◽  
X Ray ◽  
New Methods

Abstract As part of a characterization and mechanical research about hydroxyapatite (HA) plasma deposits for hip prosthesis, we addressed the problem of determining their crystallinity. A traditional normalization method employed by several laboratories is based on X-ray diffraction by a powder mixture of the investigated HA sample with a standard of crystalline powder, namely Al2O3. This method is quite unsatisfactory, as very often delivers unreasonable results. In order to overcome these difficulties we investigated some new methods for determining the crystallinity of HA sample, which are based on X-ray diffraction. All these methods provide reasonable results.

Effect of Nickel on Titanium Carbide Synthesized via Tungsten Inert Gas (TIG) Method

2012 ◽  
Vol 620 ◽  
pp. 384-388
Author(s):  
Sharifah Aishah Syed Salim ◽  
Julie Juliewatty Mohamed ◽  
Zainal Arifin Ahmad ◽  
Zainal Arifin Ahmad
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Powder Mixture ◽  
Raw Material ◽  
Inert Gas ◽  
X Ray Diffraction ◽  
X Ray ◽  
Arc Melting ◽  
Elemental Powder Mixture ◽  
Scanning Electron

Numerous methods have been used to produce high purity TiC. There is no previous study has been reported on the formation using single elemental powders of Titanium (Ti) and Carbon (C) with addition Nickel (Ni) by tungsten inert gas (TIG) weld method. In this work, TiC was synthesized via TIG method by arc melting elemental powder mixture of Ti and C at ~5 second (s) and 80 ampere (A). The effect Ni contents on TiC formation was investigated. The mixed raw material was ball milled for 24 hours followed by synthesis via TIG method. The arced samples were characterized by X-ray diffraction (XRD) and Scanning electron microscope (SEM). It was revealed, that small amount of Ni additive to the metal powder allows the production of dense and tough TiC.

scholarly journals Standard Hot Pressing as a Possible Solution to Obtain Dense K0.5Na0.5NbO3 Ceramic Doped by Er2O3 and Yb2O3

Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4171 ◽  
Author(s):  
Paweł Rutkowski ◽  
Jan Huebner ◽  
Adrian Graboś ◽  
Dariusz Kata ◽  
Dariusz Grzybek ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Rare Earth ◽  
Phase Composition ◽  
Powder Mixture ◽  
Hot Pressing ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ultrasonic Methods ◽  
Scanning Electron

In this study, the influence of the addition of rare earth oxides on the phase composition and density of KNN piezoelectric ceramics was investigated. The initial powders of Na2CO3 and K2CO3 were dried at 150 °C for 2 h. Then, a powder mixture for synthesis was prepared by adding a stoichiometric amount of Nb2O5 and 5 and 10 wt % overabundance of Na2CO3. All powders were mixed by ball-milling for 24 h and synthesized at 950 °C. The phase composition of the reaction bed was checked by means of X-ray diffraction (XRD). It had an appearance of tetragonal and monoclinic K0.5Na0.5NbO3 (KNN) phases. Then, 1 and 2 wt % of Er2O3 and Yb2O3, were added to the mixture. Green samples of 25 mm diameter and 3 mm thickness were prepared and sintered by hot pressing at 1000 °C for 2 h under 25 MPa pressure. The final samples were investigated via scanning electron microscopy (SEM)-energy-dispersive X-ray spectroscopy (EDS), XRD, Rietveld, and ultrasonic methods. Phase analysis showed tetragonal and orthorhombic KNN phases, and a contamination of (K2CO3·1.5H2O) was present. The obtained KNN polycrystals had a relative density above 95%. Texturing of the material was confirmed as a result of hot pressing.

scholarly journals Automated harvesting and processing of protein crystals through laser photoablation

2016 ◽  
Vol 72 (4) ◽  
pp. 454-466 ◽  
Author(s):  
Ulrich Zander ◽  
Guillaume Hoffmann ◽  
Irina Cornaciu ◽  
Jean-Pierre Marquette ◽  
Gergely Papp ◽  
...  
Keyword(s):  
Data Collection ◽  
Macromolecular Crystallography ◽  
X Ray Diffraction ◽  
X Ray ◽  
New Methods ◽  
Repeated Sample ◽  
Sample Recovery ◽  
Through Diffusion ◽  
X Ray Background ◽  
Low X

Currently, macromolecular crystallography projects often require the use of highly automated facilities for crystallization and X-ray data collection. However, crystal harvesting and processing largely depend on manual operations. Here, a series of new methods are presented based on the use of a low X-ray-background film as a crystallization support and a photoablation laser that enable the automation of major operations required for the preparation of crystals for X-ray diffraction experiments. In this approach, the controlled removal of the mother liquor before crystal mounting simplifies the cryocooling process, in many cases eliminating the use of cryoprotectant agents, while crystal-soaking experiments are performed through diffusion, precluding the need for repeated sample-recovery and transfer operations. Moreover, the high-precision laser enables new mounting strategies that are not accessible through other methods. This approach bridges an important gap in automation and can contribute to expanding the capabilities of modern macromolecular crystallography facilities.

scholarly journals Synthesis of NiMoO4/3D-rGO Nanocomposite in Alkaline Environments for Supercapacitor Electrodes

Crystals ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 31 ◽  
Author(s):  
Shahrzad Arshadi Rastabi ◽  
Rasoul Sarraf Mamoory ◽  
Fatemeh Dabir ◽  
Nicklas Blomquist ◽  
Manisha Phadatare ◽  
...  
Keyword(s):  
Synergistic Effects ◽  
Ammonia Solution ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
New Methods ◽  
Alkaline Environments ◽  
Pseudocapacitive Behavior ◽  
Ammonia Addition ◽  
A New Technique

Although Graphene oxide (GO)-based materials is known as a favorable candidate for supercapacitors, its conductivity needs to be increased. Therefore, this study aimed to investigate the performance of GO-based supercapicitor with new methods. In this work, an ammonia solution has been used to remove the oxygen functional groups of GO. In addition, a facile precipitation method was performed to synthesis a NiMoO4/3D-rGO electrode with purpose of using synergistic effects of rGO conductivity properties as well as NiMoO4 pseudocapacitive behavior. The phase structure, chemical bands and morphology of the synthesized powders were investigated by X-ray diffraction (XRD), Raman spectroscopy, and field emission secondary electron microscopy (FE-SEM). The electrochemical results showed that the NiMoO4/3D-rGO(II) electrode, where ammonia has been used during the synthesis, has a capacitive performance of 932 Fg−1. This is higher capacitance than NiMoO4/3D-rGO(I) without using ammonia. Furthermore, the NiMoO4/3D-rGO(II) electrode exhibited a power density of up to 17.5 kW kg−1 and an energy density of 32.36 Wh kg−1. These results showed that ammonia addition has increased the conductivity of rGO sheets, and thus it can be suggested as a new technique to improve the capacitance.

Microstructure and Properties of Multi-Function Micro-Plasma Sprayed Al2O3 Coatings

2008 ◽  
Vol 373-374 ◽  
pp. 51-54 ◽  
Author(s):  
Shao Chun Hua ◽  
Han Gong Wang ◽  
Liu Ying Wang ◽  
Gu Liu
Keyword(s):  
Particle Velocity ◽  
Plasma Spray ◽  
Bonding Strength ◽  
Main Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Microstructure And Properties ◽  
Powder Feed ◽  
Α Al2o3 ◽  
Plasma Sprayed

Al2O3 coatings were fabricated by multi-functional micro-plasma spray through axial powder feed. The flight particle velocity and temperature were measured by SprayWatch-2i. With the rising of Ar flow, the velocity of Al2O3 particles increases, but the temperature of particles decreases gradually. Al2O3 coatings were analyzed by SEM and XRD. The microstructure of coatings is density, low porosity and uniform morphology. X-ray diffraction results show that α-Al2O3 is the main phase in the original Al2O3 powders, but Al2O3 coatings consist of γ-Al2O3 and a small amount of α-Al2O3. The microhardness and bonding strength of Al2O3 coatings were also measured, which is HV0.11183~1387 and 28.6MPa, respectively.

X-ray diffraction study on the amorphization of the Pd80Si20 powder mixture by mechanical alloying

1993 ◽  
Vol 68 (6) ◽  
pp. 833-844 ◽  
Author(s):  
S. Martelli ◽  
W. Guo ◽  
M. Magini ◽  
F. Padella ◽  
D. Zedda
Keyword(s):  
Mechanical Alloying ◽  
Diffraction Study ◽  
Powder Mixture ◽  
X Ray Diffraction ◽  
X Ray

New methods for diffraction stress measurement: a critical evaluation of new and existing methods

2000 ◽  
Vol 33 (4) ◽  
pp. 1059-1066 ◽  
Author(s):  
J.-D. Kamminga ◽  
Th. H. de Keijser ◽  
E. J. Mittemeijer ◽  
R. Delhez
Keyword(s):  
Stress Analysis ◽  
Elastic Constants ◽  
Stress Measurement ◽  
Critical Evaluation ◽  
Polycrystalline Materials ◽  
X Ray Diffraction ◽  
X Ray ◽  
New Methods

New methods of diffraction stress analysis of polycrystalline materials, consisting of cubic elastically anisotropic crystallites, are proposed and compared with existing methods. Whereas for the existing methods knowledge of the diffraction elastic constants is presupposed, three new methods are presented that require only knowledge of the (macroscopic) mechanical elastic constants. The stress values obtained with these new methods on the basis of the mechanical elastic constants are more reliable than those obtained with the methods on the basis of the diffraction elastic constants. New and existing methods are illustrated by means of measurements of X-ray diffraction from a magnetron-sputtered TiN layer.

INFLUENCE OF THE INDEX METALLIC SALTS - COMPLEXING AGENT IN A SOL-GEL PROCESS TO OBTAIN NANOSCALED ZIRCONIUM SUBSTITUTED YTTRIUM (YSZ) TO ELECTROLYTE APPLICATION IN SOLID OXIDE FUEL CELL (SOFC)

2012 ◽  
Vol 1386 ◽  
Author(s):  
Rene Fabian Cienfuegos-Pelaes ◽  
Alejandro Ehécatl Correa ◽  
Ramona Alicia Salazar ◽  
L. Chávez-Guerrero ◽  
M. Hinojosa
Keyword(s):  
Low Cost ◽  
Sol Gel ◽  
Complexing Agents ◽  
Complexing Agent ◽  
X Ray Diffraction ◽  
Crystalline Powder ◽  
Easy Method ◽  
X Ray ◽  
Metallic Salts ◽  
Sol Gel Process

ABSTRACTThe objective of the present study is to obtain the electrolyte material YSZ at low cost via sol gel, through exploration of the index rate between the complexing agents and the metallic salts (HMTA / metallic salts) from 1 to 5, prepared by a polymeric way in a sol gel process. We show an easy method that could be used in the industrial scale in order to obtain solid electrolyte material for its application in SOFC to operate at temperatures in the range of 700 800°C. This study has as reference the papers from Lenormand and Rieu about their synthesis of zirconium substituted to 8% of yttrium (CYSZ= 0.2 mol*L-1 metallic salts concentration-). The presence of the phase in the materials has been confirmed by X-ray diffraction assisted by thermal analysis tests, for indexes from 2 to 5 at a temperature of 1000°C for 5 hours at a calcination rate (from amorphous dust obtained at 400°C) of 1000°C per hour. The grain size mean for crystalline powder has an average near 50 nm and standard deviation close to 9 nm, it was confirmed by scanning electron microscope (SEM).

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