Effect of local ordering around Th4+ ions in glycine-nitrate precursor gel on the powder characteristic of gel-combusted ThO2

2019 ◽  
Vol 527 ◽  
pp. 151826 ◽  
Author(s):  
Dheeraj Jain ◽  
V. Sudarsan ◽  
A.K. Patra ◽  
P.U. Sastry ◽  
A.K. Tyagi
Keyword(s):  
Local Ordering ◽  
Nitrate Precursor

Electron-diffraction studies of amorphous carbon thin films

1993 ◽  
Vol 51 ◽  
pp. 1100-1101
Author(s):  
David A. Muller
Keyword(s):  
Thin Films ◽  
Electron Diffraction ◽  
Amorphous Carbon ◽  
Glassy Carbon ◽  
Spherical Structure ◽  
Local Ordering ◽  
Carbon Arc ◽  
Similar Appearance ◽  
Carbon Thin Films ◽  
Large Spherical

The sp2 rich amorphous carbons have a wide variety of microstructures ranging from flat sheetlike structures such as glassy carbon to highly curved materials having similar local ordering to the fullerenes. These differences are most apparent in the region of the graphite (0002) reflection of the energy filtered diffracted intensity obtained from these materials (Fig. 1). All these materials consist mainly of threefold coordinated atoms. This accounts for their similar appearance above 0.8 Å-1. The fullerene curves (b,c) show a string of peaks at distance scales corresponding to the packing of the large spherical and oblate molecules. The beam damaged C60 (c) shows an evolution to the sp2 amorphous carbons as the spherical structure is destroyed although the (220) reflection in fee fcc at 0.2 Å-1 does not disappear completely. This 0.2 Å-1 peak is present in the 1960 data of Kakinoki et. al. who grew films in a carbon arc under conditions similar to those needed to form fullerene rich soots.

Processing and characterization of YBa2Cu3O7−x/Ag composites

1990 ◽  
Vol 48 (4) ◽  
pp. 46-47
Author(s):  
Jafar Javadpour ◽  
Bradley L. Thiel ◽  
Sarikaya Mehmet ◽  
Ilhan A. Aksay
Keyword(s):  
Composite System ◽  
Precursor Solution ◽  
Microstructural Development ◽  
Superconducting Properties ◽  
Practical Applications ◽  
Nitrate Precursor ◽  
Cold Pressed ◽  
Tape Cast ◽  
Composite Samples

Practical applications of bulk YBa2Cu3O7−x materials have been limited because of their inadequate critical current density (jc) and poor mechanical properties. Several recent reports have indicated that the addition of Ag to the YBa2Cu3O7−x system is beneficial in improving both mechanical and superconducting properties. However, detailed studies concerning the effect of Ag on the microstructural development of the cermet system have been lacking. Here, we present some observations on the microstructural evolution in the YBa2Cu3O7−x/Ag composite system.The composite samples were prepared by mixing various amounts (2.5 - 50 wt%) AgNO3 in the YBa2Cu3O7−x nitrate precursor solution. These solutions were then spray dried and the resulting powders were either cold pressed or tape cast. The microstructures of the sintered samples were analyzed using SEM (Philips 515) and an analytical TEM (Philips 430T).The SEM micrographs of the compacts with 2.5 and 50 wt% Ag addition sintered at 915°C (below the melting point of Ag) for 1 h in air are displayed in Figs. 1 and 2, respectively.

Short-range order and concentration fluctuations in binary molten alloys

1987 ◽  
Vol 65 (3) ◽  
pp. 309-325 ◽  
Author(s):  
R. N. Singh
Keyword(s):  
Lattice Theory ◽  
Order Parameter ◽  
Short Range ◽  
Short Range Order ◽  
Range Order ◽  
Concentration Fluctuations ◽  
Mixing Properties ◽  
Chemical Theory ◽  
Local Ordering ◽  
Interchange Energy

The quasi-chemical theory and the quasi-lattice theory are discussed with a view to obtaining information about concentration fluctuations, SCC(0), and the short-range order parameter, α1, for regular and compound-forming molten alloys. The influence of the coordination number z and the interchange energy ω on the mixing properties of the alloy is critically examined. SCC(0) and α1 have been found to be very useful in extracting microscopic information, like local ordering and segregation in molten systems. The problem of glass formation in compound-forming binary molten alloys is also briefly discussed.

scholarly journals Local Ordering of Molten Salts at NiO Crystal Interfaces Promotes High‐index Faceting

2021 ◽  
Author(s):  
Raffaele Cheula ◽  
Mariano D. Susman ◽  
David H. West ◽  
Sivadinarayana Chinta ◽  
Jeffrey D. Rimer ◽  
...  
Keyword(s):  
Molten Salts ◽  
High Index ◽  
Local Ordering ◽  
Crystal Interfaces

Optimization of Green Synthesis Approach of Silver Nanoparticles Using Indonesian Wild Honey

2021 ◽  
Vol 891 ◽  
pp. 111-115
Author(s):  
Maradhana Agung Marsudi ◽  
Farah Fitria Sari ◽  
Pandu Mauliddin Wicaksono ◽  
Adinda Asmoro ◽  
Arif Basuki ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Silver Nanoparticles ◽  
Green Synthesis ◽  
Synthesis Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Particle Count ◽  
Transmission Electron ◽  
Nitrate Precursor ◽  
Synthesis Approach

In this work, silver nanoparticles have been successfully synthesized using simple and environmentally friendly ‘green synthesis’ method using Indonesian wild honey as mediator. Particle count and size can be optimized by varying the silver nitrate precursor and honey concentration, with the help of sodium hydroxide as pH regulator. Based on X-ray diffraction (XRD) result, crystalline structure of Ag has been confirmed in sample with impurities from AgCl. Based on dynamic light scattering (DLS) and transmission electron microscopy (TEM) results, it was found that the smallest average particles size of AgNPs (117.5 nm from DLS and 11.1 nm from TEM) was obtained at sample with 5% w/v of honey and 0.5 mM of AgNO3.

scholarly journals Fabrication of α-alumina fibers by sol-gel and electrospinning of aluminum nitrate precursor solutions

2019 ◽  
Vol 12 ◽  
pp. 193-204 ◽  
Author(s):  
José Hafid Roque-Ruiz ◽  
Nahúm A. Medellín-Castillo ◽  
Simón Yobanny Reyes-López
Keyword(s):  
Sol Gel ◽  
Aluminum Nitrate ◽  
Nitrate Precursor ◽  
Alumina Fibers
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