THE EFFECT OF CeO2 NANOPARTICLE DOPING ON REFINEMENT OF Y-211 PARTICLES IN POIG PROCESSED YBCO COMPOSITES

Doping of non-interacting nanoparticles in YBCO superconductors in order to get fine microstructure defects has been studied. Y-211 inclusion, itself has large potential to create structural defects without affecting Y-123 matrix phase. Nanoparticles of grain refining agent like CeO2/Pt/PtO2 are interesting dopants, especially CeO2 for being cheaper than Pt. POIG process, as is one of the advance processing techniques to get uniform distribution of fine Y-211 particles of the order of 1-2 μm, throughout the YBCO composites. Finer Y-211 particles can drastically increase the pinning centers. Introduction of fine sized CeO2 as grain refining agent to reduce the size of Y-211 particles would create additional pinning centers. In the present work, the effect of CeO2 on Y-211size and distribution in POIG processed YBCO composite was studied. It was observed that with increase in CeO2 content Y-211 particle size decreases below 1μm and even less than 0.5μm for 10 weight percent CeO2 doping. The mechanism for refinement appears to be the formation of BaCeO3 on the surface of Y-211 during liquid phase infiltration that leads to splitting of Y-211 into smaller particles.

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Silicon layers grown over SiO2 by liquid phase epitaxy: Electron Microscopical study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010017596x ◽

1990 ◽

Vol 48 (4) ◽

pp. 566-567

Author(s):

F. Banhart ◽

F.O. Phillipp ◽

R. Bergmann ◽

E. Czech ◽

M. Konuma ◽

...

Keyword(s):

Electron Microscopy ◽

Liquid Phase ◽

Plasma Etching ◽

Liquid Phase Epitaxy ◽

Three Dimensional ◽

Microscopical Study ◽

Sample Temperature ◽

Structural Defects ◽

Si Substrates ◽

Etched Surface

Defect-free silicon layers grown on insulators (SOI) are an essential component for future three-dimensional integration of semiconductor devices. Liquid phase epitaxy (LPE) has proved to be a powerful technique to grow high quality SOI structures for devices and for basic physical research. Electron microscopy is indispensable for the development of the growth technique and reveals many interesting structural properties of these materials. Transmission and scanning electron microscopy can be applied to study growth mechanisms, structural defects, and the morphology of Si and SOI layers grown from metallic solutions of various compositions.The treatment of the Si substrates prior to the epitaxial growth described here is wet chemical etching and plasma etching with NF3 ions. At a sample temperature of 20°C the ion etched surface appeared rough (Fig. 1). Plasma etching at a sample temperature of −125°C, however, yields smooth and clean Si surfaces, and, in addition, high anisotropy (small side etching) and selectivity (low etch rate of SiO2) as shown in Fig. 2.

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Effect of particle size and weight percent of different wood dust on the tensile strength of glass fiber Epoxy/Saw dust composite using RSM

Materials Today Proceedings ◽

10.1016/j.matpr.2021.03.635 ◽

2021 ◽

Author(s):

Shailendra Singh Chauhan ◽

Nagendra Kumar Maurya ◽

Shashi Prakash Dwivedi

Keyword(s):

Particle Size ◽

Tensile Strength ◽

Glass Fiber ◽

Weight Percent ◽

Wood Dust ◽

Saw Dust ◽

Effect Of Particle Size

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Effect of Particle Size on Monometallic and Bimetallic (Au,Pd)/C on the Liquid Phase Oxidation of Glycerol

Catalysis Letters ◽

10.1007/s10562-006-0036-8 ◽

2006 ◽

Vol 108 (3-4) ◽

pp. 147-153 ◽

Cited By ~ 156

Author(s):

Nikolaos Dimitratos ◽

Jose Antonio Lopez-Sanchez ◽

David Lennon ◽

Francesca Porta ◽

Laura Prati ◽

...

Keyword(s):

Particle Size ◽

Liquid Phase ◽

Liquid Phase Oxidation ◽

Phase Oxidation ◽

Effect Of Particle Size

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Evaluation of Particle Size Distribution Using an Efficient Approach Based on Image Processing Techniques

Iranian Journal of Science and Technology Transactions of Civil Engineering ◽

10.1007/s40996-018-0175-3 ◽

2018 ◽

Vol 43 (S1) ◽

pp. 429-441 ◽

Cited By ~ 2

Author(s):

Majid Damadipour ◽

Mehdi Nazarpour ◽

Mohammad Taghi Alami

Keyword(s):

Image Processing ◽

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Image Processing Techniques ◽

Efficient Approach ◽

Processing Techniques

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Multiscale Analysis of Particle Size-dependent Steady Compaction Waves in Granular Energetic Materials

International Journal of Nonlinear Sciences and Numerical Simulation ◽

10.1515/ijnsns.2011.117 ◽

2012 ◽

Vol 13 (2) ◽

pp. 165-175

Author(s):

Xin-Ming Zhang ◽

Yan-Qing Wu ◽

Feng-Lei Huang

Keyword(s):

Particle Size ◽

Liquid Phase ◽

Yield Strength ◽

Thermal Energy ◽

Coarse Particles ◽

Localization Strategy ◽

Solid Liquid ◽

Particle Beds ◽

Compaction Waves ◽

Grain Temperature

Abstract A multiscale model is used to analyze the compaction processes in granular HMX beds composed of different particle sizes (coarse particles, d=40 μm and microfine particles, d=4 μm). The localization strategy of Gonthier is extended to include changes in thermal energy induced by compression. The variation in yield strength caused by solid-liquid phase change is also considered. Analysis of the steady-state wave structure indicates that the compaction behavior of a porous material is dependent on particle size. For solid volume fraction φs < 0.88, the fine particle beds provide greater resistance to compaction than the coarse particle beds, and they propagate compaction waves that travel at faster speeds. When φs > 0.88, the physical state of the compacted bed has become very similar for the two materials. For subsonic compaction waves, the evolution of the grain temperature shows that large particles lead to large hot spots and high temperature and coarse particles are more shock sensitive at low shock pressures. For supersonic compaction waves, compression induced changes in thermal energy play an important role in localization strategy. It increases the localization sphere center radius. The dissipated energy is deposited over a larger localization volume so that the grain temperature near the intergranular contact surface is reduced significantly. The localization center radius further increases because of the decrease in the yield strength caused by solid–liquid phase change. Consequently, the peak grain temperature is reduced further.

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