Results 31 to 40 of about 247 (181)
Effect of Cr2O3 on properties of ZnO-Bi2O3 based high-voltage varistor ceramics
ZnO-Bi2O3-Co2O3-NiO-Mn3O4-SiO2-Cr2O3 varistor ceramics were prepared by solid-phase sintering method.The effects of different doping amounts of Cr2O3 on the microstructure and electrical properties of ZnO varistor ceramics were investigated, and the ...
GUI Yanghai +5 more
doaj +1 more source
Modeling of electrical transport in Zinc Oxide varistors [PDF]
The electrical transport in zinc oxide (ZnO) varistors is analyzed using microstructural material modeling. The fully three dimensional current distribution is computed by means of a nonlinear equivalent circuit model representing the assembly of current
K. Bavelis, E. Gjonaj, T. Weiland
doaj +1 more source
Varistores à base de SnO2 foram preparados pelo processo convencional de mistura de óxidos. As amostras foram sinterizadas a 1250 °C por 2 h. Os difratogramas obtidos por difração de raios X e as análises por microscopia eletrônica de varredura ...
M. M. Oliveira +6 more
doaj +1 more source
Microstructural evaluation of rare-earth-zinc oxide-based varistor ceramics
Zinc oxide varistors are nonlinear voltage dependent ceramic resistors used to suppress and limit transient voltage surges. The work reported in this paper involves the relationship between microstructural characteristics and the varistor performance of ...
José Geraldo de Melo Furtado +4 more
doaj +1 more source
Highly stable ZnO varistor ceramics with steadily decreasing power loss have been put into applications in electrical and electronic systems for overvoltage protections, even with the absence of general understandings on their aging behaviors.
Zhuolin Cheng +5 more
doaj +1 more source
Synthesis of ZnO based nanopowders via a non-hydrolytic sol gel technique and their densification behaviour and varistor properties [PDF]
Hexagonal nanocrystalline varistor grade ZnO particles with size 50 nm and the specific surface area of 28 m2/g have been prepared by non-aqueous gelation technique involving diethylene glycol and triethanolamine.
Shereef Anas +4 more
doaj
Abstract Electromagnetic sounding coupled with experimental measurements of electrical conductivity (EC) can provide valuable constraints on the thermochemical state of Earth's lower mantle. Here, we report a new set of experimentally determined EC values of pyrolite, a candidate composition of the lower mantle, between 25 and 80 GPa at room ...
Charlotte Trubowitz +10 more
wiley +1 more source
Comparative Studies on Degradation of Varistors Subjected to Operation in Surge Arresters and Surge Arrester Counters [PDF]
The paper presents results of investigation of microstructure and micro-hardness for material of ZnO varistors applied to 110 kV surge arrester and surge arrester counter.
P. Papliński +6 more
doaj +1 more source
Strain‐Induced Redistribution of Point Defects in ZnO Nanoparticles
Powder compaction generates local strain effects in ZnO nanoparticles. This alters the abundance of intrinsic point defects and impacts the semiconductor's electronic structure. Such changes were analyzed by a combination of spectroscopy and density functional theory calculations and emphasize the importance of strain effects in the design and ...
Korbinian Aicher +4 more
wiley +1 more source
Microstructural Characterization of ZnO Varistors.
Two kinds of commercial ZnO system varistors were investigated with relevance to their microstructures. Particularly, face-to-face fracture surfaces were characterized in terms of secondary electron image and backscatterd electron image to clarify the existence of precipitates at the grain-to-grain interface.
Takeda, Shunji +2 more
openaire +2 more sources

