A neutron diffraction study on a typical highly defective ceria–yttria solid solution

2002 ◽  
Vol 17 (4) ◽  
pp. 278-280 ◽  
Author(s):  
Keka R. Chakraborty ◽  
S. V. Chavan ◽  
A. K. Tyagi
Keyword(s):  
Solid Solution ◽  
Diffraction Study ◽  
Room Temperature ◽  
Fluorite Structure ◽  
Neutron Diffraction Study ◽  
Neutron Powder Diffraction ◽  
Face Centered Cubic ◽  
Aliovalent Substitution ◽  
Face Centered ◽  
The Ideal

It was seen during the phase relation studies on the CeO2–YO1.5 system that the ceria is able to accommodate a large anion deficiency caused by aliovalent substitution. A neutron powder diffraction study has been carried out at room temperature for the titled solid solution, Ce1−xYxO2−x/2 with x=0.32, which is an anion-deficient variant of the ideal fluorite structure. The structure has been found to be face centered cubic. No superlattice reflections have been observed indicating that the vacancies occupy the random positions in this highly defective solid solution. The bond distances and angles are also being reported.

scholarly journals In Situ Synthesis of Polyaniline Based Ceramic Wastes Composites: Dielectric and Electrical Properties

2021 ◽  
Author(s):  
M. Sohail ◽  
Adnan Shahzad ◽  
Mian Gul Sayed ◽  
Ihsan Ullah ◽  
M. Omer ◽  
...  
Keyword(s):  
Composite Material ◽  
High Frequency ◽  
Room Temperature ◽  
In Situ Synthesis ◽  
Face Centered Cubic ◽  
Dielectric Analysis ◽  
Photovoltaic Detectors ◽  
Pani Composite ◽  
Face Centered

Abstract In the present study, ceramic wastes collected from the premises of industrial zone in Peshawar, KP Pakistan were investigated. An effort has been made to recycle and use the ceramic wastes as fillers in polymeric composites. The negative cost ceramic wastes were purified and activated thermally. The elemental composition and pellets of the wastes were investigated through SEM/EDX analysis. Waste/Polyaniline (PANI) composite was synthesized via in-situ free radical polymerization technique. SEM of the composites showed the uniform distribution of fillers particles in the PANI matrix. XRD studies confirmed that the prepared composite material had a face- centered cubic geometry with distinct preferential orientations. Dielectric analysis showed that the materials exhibit active performance at high frequency regions (3MHz to 3GHz) at room temperature. The results show decrease in dielectric losses and capacitance (1.6 pF) at high frequency regions. AC conductivity of the composite has been increased up to 37.95 Scm-1. This revealed the effect of PANI on the ceramic wastes while increasing its conductance performance. This suggests that the composite material can be investigated for use in photovoltaic detectors, electro-responsive capacitors and power applications.

scholarly journals Ti-V-C-Based Alloy with a FCC Lattice Structure for Hydrogen Storage

Molecules ◽  
2019 ◽  
Vol 24 (3) ◽  
pp. 552
Author(s):  
Bo Li ◽  
Liqing He ◽  
Jianding Li ◽  
Hai-Wen Li ◽  
Zhouguang Lu ◽  
...  
Keyword(s):  
Hydrogen Storage ◽  
Room Temperature ◽  
Lattice Structure ◽  
Activation Process ◽  
Face Centered Cubic ◽  
Hydrogen Storage Materials ◽  
Fcc Lattice ◽  
Bcc Structure ◽  
Face Centered ◽  
Fcc Structure

Here we report a Ti50V50-10 wt.% C alloy with a unique lattice and microstructure for hydrogen storage development. Different from a traditionally synthesized Ti50V50 alloy prepared by a melting method and having a body-centered cubic (BCC) structure, this Ti50V50-C alloy synthesized by a mechanical alloying method is with a face-centered cubic (FCC) structure (space group: Fm-3m No. 225). The crystalline size is 60 nm. This alloy may directly absorb hydrogen near room temperature without any activation process. Mechanisms of the good kinetics from lattice and microstructure aspects were discussed. Findings reported here may indicate a new possibility in the development of future hydrogen storage materials.

scholarly journals Pressure-Induced Dimerization of C60 at Room Temperature as Revealed by an In Situ Spectroscopy Study Using an Infrared Laser

Crystals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 182 ◽  
Author(s):  
Bing Li ◽  
Jinbo Zhang ◽  
Zhipeng Yan ◽  
Meina Feng ◽  
Zhenhai Yu ◽  
...  
Keyword(s):  
Room Temperature ◽  
Infrared Laser ◽  
Face Centered Cubic ◽  
X Ray Diffraction ◽  
Simple Cubic ◽  
Excitation Laser ◽  
Face Centered ◽  
830 Nm Laser ◽  
Structure Evaluation

Using in situ high-pressure Raman spectroscopy and X-ray diffraction, the polymerization and structure evaluation of C60 were studied up to 16 GPa at room temperature. The use of an 830 nm laser successfully eliminated the photo-polymerization of C60, which has interfered with the pressure effect in previous studies when a laser with a shorter wavelength was used as excitation. It was found that face-centered cubic (fcc) structured C60 transformed into simple cubic (sc) C60 due to the hint of free rotation for the C60 at 0.3 GPa. The pressure-induced dimerization of C60 was found to occur at about 3.2 GPa at room temperature. Our results suggest the benefit and importance of the choice of the infrared laser as the excitation laser.

Technical Study on Preparation of Co/C Composite Nanofibers via Electrospinning

2019 ◽  
Vol 944 ◽  
pp. 666-670
Author(s):  
Sa Zhang ◽  
Jian Jiang Wang ◽  
Fang Zhao
Keyword(s):  
Composite Nanofibers ◽  
Cobalt Acetate ◽  
Organic Salt ◽  
Face Centered Cubic ◽  
Composite Fibers ◽  
Fiber Morphology ◽  
Preparation Technology ◽  
Technical Study ◽  
Face Centered ◽  
The Ideal

Co/C composite nanofibers are prepared through electrospinning. Effect of salt, Spinning humidity, receiving equipment and heat treatment on the formation, morphology and structure of composite fibers were investigated. The morphology of composite fibers was observed by scanning electron microscopy (SEM).It was found out that when the ambient humidity was high, the nanofibers were agglomerated into fiber bundles. When the roller receiving equipment was used, ordered nanofibers can be obtained. Only cobalt acetate-doped composite nanofibers maintained intact fiber morphology after pre-oxidation and carbonization. And Co2+ was completely reduced to face-centered cubic structured Co nanoparticle. The ideal preparation technology is as follows: the humidity at 30% or less, doping with organic salt of cobalt acetate.

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