The influence of multifunctional microalloyed ceramics microstructure on its capacity properties

Modified porous alumo-silicate ceramics, alloyed with magnesium and microalloyed with aluminum, belongs to modern multifunctional ceramic materials. Microalloying has led to important changes in dielectric and electrical properties of ceramics, such as dielectric constant and electrical resistance. These changes are conditioned by the microstructural properties of modified porous ceramics. The obtained results have shown the unity of the influence of composition, structure, morphology and application of microalloyed multifunctional alumosilicate ceramics on electrophysical properties. Microstructural investigations have shown that this type of ceramics has an amorphous-crystal structure, which causes important changes in its electrical properties and affects its activity. Therefore the ceramics can be considered as an active dielectric. A correlation between microstructural properties and structurally sensitive, i.e. electrophysical properties of microalloyed multifunctional alumo-silicate ceramics, was confirmed.

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Fabrication and studying the dielectric properties of (polystyrene-copper oxide) nanocomposites for piezoelectric application

Bulletin of Electrical Engineering and Informatics ◽

10.11591/eei.v8i1.1019 ◽

2019 ◽

Vol 8 (1) ◽

pp. 52-57 ◽

Cited By ~ 6

Author(s):

Dalal Hassan ◽

Ahmed Hashim Ah-yasari

Keyword(s):

Electrical Conductivity ◽

Dielectric Constant ◽

Dielectric Properties ◽

Electrical Properties ◽

Dielectric Loss ◽

Copper Oxide ◽

Electrical Resistance ◽

Copper Oxide Nanoparticles ◽

Oxide Nanoparticles ◽

Increase With Increase

The preparation of (polystyrene-copper oxide) nanocomposites have been investigated for piezoelectric application. The copper oxide nanoparticles were added to polystyrene by different concentrations are (0, 4, 8 and 12) wt.%. The structural and A.C electrical properties of (PS-CuO) nanocomposites were studied. The results showed that the dielectric constant and dielectric loss of (PS-CuO) nanocomposites decrease with increase in frequency. The A.C electrical conductivity increases with increase in frequency. The dielectric constant, dielectric loss and A.C electrical conductivity of polystyrene increase with increase in copper oxide nanoparticles concentrations. The results of piezoelectric application showed that the electrical resistance of (PS-CuO) nanocomposites decreases with increase in pressure.

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Controlled Reduction of Vanadium Oxide Nanoscrolls: Crystal Structure, Morphology, and Electrical Properties

Chemistry of Materials ◽

10.1021/cm801539f ◽

2008 ◽

Vol 20 (20) ◽

pp. 6396-6404 ◽

Cited By ~ 65

Author(s):

Serena A. Corr ◽

Madeleine Grossman ◽

Joshua D. Furman ◽

Brent C. Melot ◽

Anthony K. Cheetham ◽

...

Keyword(s):

Crystal Structure ◽

Electrical Properties ◽

Vanadium Oxide ◽

Structure Morphology

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Influence of Hydrothermal Conditions on ZST Powders for Microwave Ceramics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.269 ◽

2007 ◽

Vol 336-338 ◽

pp. 269-271

Author(s):

D.Y. Bao ◽

Zhao Xian Xiong

Keyword(s):

Crystal Structure ◽

Dielectric Constant ◽

Dielectric Properties ◽

Hydrothermal Synthesis ◽

Theoretical Density ◽

Microwave Ceramics ◽

Hydrothermal Conditions ◽

X Ray ◽

Structure Morphology ◽

Mean Size

(Zr0.8Sn0.2)TiO4 nanopowders for microwave ceramics were prepared by a hydrothermal synthesis route. Effects of hydrothermal conditions on crystal structure, morphology and sintering performance of the powders were characterized by X-ray, SEM and TG-DTA, respectively. The powders with mean size of 80 ~ 200 nm was obtained. Ceramics with 92.3% of theoretical density were fabricated at 1260°C with the powders. Dielectric properties of the samples were measured and it gives a dielectric constant of 35-36 and Q×f value of 4500-10000 GHz.

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Structural, Thermal and Electrical Properties of Doped Poly(3,4 ethylenedioxythiophene)

Chemistry & Chemical Technology ◽

10.23939/chcht10.04.395 ◽

2016 ◽

Vol 10 (4) ◽

pp. 395-400 ◽

Cited By ~ 1

Author(s):

Deepali Kelkar ◽

◽

Ashish Chourasia ◽

◽

Keyword(s):

Crystal Structure ◽

Electrical Properties ◽

Xrd Analysis ◽

Structure Modification ◽

Camphorsulfonic Acid ◽

Thermal And Electrical Properties ◽

Ft Ir

Poly(3,4-ethylenedioxythiophene) (PEDOT) was chemically synthesized, undoped and then re-doped using FeCl3 as well as camphorsulfonic acid (CSA). FT-IR results confirm the nature of the synthesized and doped samples. XRD analysis indicates crystal structure modification after doping and was also used to calculate crystallinity of samples. Crystallinity increases after FeCl3 doping, whereas it reduces due to CSA doping. TGA-DTA results show reduction in Tg value for FeCl3 doped sample while it increases for CSA doped samples compared to that of undoped PEDOT. Reduction in Tg indicates plasticizing effect of FeCl3 whereas increase in Tg show anti-plasticizing effect of CSA in PEDOT. Conductivity value () increases by two orders of magnitude after doping. Log vs. 1/T graph show metallic nature of undoped PEDOT above 308 K, however both doped samples show semiconducting nature from 301 to 383 K.

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Perspective Biomass Carrier for Anaerobic Processing Systems of Organic Waste AIC

Elektrotekhnologii i elektrooborudovanie v APK ◽

10.22314/2658-4859-2020-67-1-148-155 ◽

2020 ◽

Vol 67 (1) ◽

pp. 148-155

Author(s):

Anatoliy V. Fedotov ◽

Viktor S. Grigoriev ◽

Dmitriy A. Kovalev ◽

Andrey A. Kovalev

Keyword(s):

Wastewater Treatment ◽

Anaerobic Digestion ◽

Specific Surface ◽

Organic Waste ◽

Porous Ceramic ◽

Experimental Studies ◽

Ceramic Materials ◽

Porous Ceramics ◽

Developed Surface ◽

Highly Porous

To speed up the wastewater treatment under aerobic conditions and to optimize the processes of anaerobic wastewater treatment in digesters, immobilization technologies of microorganisms and enzymes on solid carriers are used. Ceramic carriers based on aluminosilicates and alumina are one of the promising inorganic biomass carriers. (Research purpose) To study the structure of porous ceramic biomass carriers for anaerobic processing of organic waste and evaluate the prospects for their use. (Materials and methods) The substrate for anaerobic digestion was a mixture of sediments of the primary and secondary sewage sumps of the Lyubertsy treatment facilities. K-65 cattle feed was used to ensure the constancy of the composition of organic substances in substrates as a cosubstrate. The authors used the method of low-temperature nitrogen adsorption of Bruner-Emmett-Teller to study the pore structure and specific surface of solid carriers on a specific surface analyzer Quntachrome Autosorb-1. (Results and discussion) The main characteristics (specific surface, volume of micro- and mesopores, predominant pore radius, water absorption and others) of chamotte foam lightweight and highly porous corundum ceramics were determined. It was revealed that ceramic materials with a developed surface and electrically conductive material provided an increase in biogas yield by 3.8-3.9 percent with an increase in methane content by an average of 5 percent. (Conclusions) The results of anaerobic digestion showed a positive effect of both a conductive carrier and highly porous ceramic materials on the process of anaerobic bioconversion of organic waste into biogas. It is advisable to expand experimental studies on the use of a conductive carrier with a developed surface based on highly porous ceramics.

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Production of Porous Ceramic Materials from Spent Fluorescent Lamps

Applied Sciences ◽

10.3390/app11136056 ◽

2021 ◽

Vol 11 (13) ◽

pp. 6056

Author(s):

Egle Rosson ◽

Acacio Rincón Rincón Romero ◽

Denis Badocco ◽

Federico Zorzi ◽

Paolo Sgarbossa ◽

...

Keyword(s):

Rare Earth ◽

Rare Earth Elements ◽

High Speed ◽

Porous Ceramic ◽

Ceramic Materials ◽

Porous Ceramics ◽

Fluorescent Lamps ◽

Naoh Solution ◽

Commercial Glass ◽

Triton X

Spent fluorescent lamps (SFL) are classified as hazardous materials in the European Waste Catalogue, which includes residues from various hi-tech devices. The most common end-of-life treatment of SFL consists in the recovery of rare earth elements from the phosphor powders, with associated problems in the management of the glass residues, which are usually landfilled. This study involves the manufacturing of porous ceramics from both the coarse glass-rich fraction and the phosphor-enriched fraction of spent fluorescent lamps. These porous materials, realizing the immobilization of Rare Earth Elements (REEs) within a glass matrix, are suggested for application in buildings as thermal and acoustic insulators. The proposed process is characterized by: (i) alkaline activation (2.5 M or 1 M NaOH aqueous solution); (ii) pre-curing at 75 °C; (iii) the addition of a surfactant (Triton X-100) for foaming at high-speed stirring; (iv) curing at 45 °C; (v) viscous flow sintering at 700 °C. All the final porous ceramics present a limited metal leaching and, in particular, the coarse glass fraction activated with 2.5 M NaOH solution leads to materials comparable to commercial glass foams in terms of mechanical properties.

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Studies on crystal structure, morphology, optical and photoluminescence properties of flake-like Sb doped Y2O3 nanostructures

Journal of Optics ◽

10.1007/s12596-021-00746-3 ◽

2021 ◽

Author(s):

Vinayak Adimule ◽

Basappa C. Yallur ◽

Kalpana Sharma

Keyword(s):

Crystal Structure ◽

Photoluminescence Properties ◽

Structure Morphology

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Effect Of Moisture On The Physical Properties Of Polyimide Films

MRS Proceedings ◽

10.1557/proc-227-147 ◽

1991 ◽

Vol 227 ◽

Cited By ~ 4

Author(s):

Rajeevi Subramanian ◽

Michael T. Pottiger ◽

Jacqueline H. Morris ◽

Joseph P. Curilla

Keyword(s):

Dielectric Constant ◽

Steady State ◽

Electrical Properties ◽

Relative Humidity ◽

Quartz Crystal ◽

Moisture Absorption ◽

Relative Dielectric Constant ◽

Moisture Uptake ◽

Polyimide Films ◽

Effect Of Moisture

ABSTRACTMoisture absorption and its effect on electrical properties were measured for several polyimides. A Quartz Crystal Microbalance (QCM) was used to investigate the moisture absorption in BPDA/PPD, PMDA/ODA, and BTDA//ODA/MPD polyimides. The steady-state moisture uptake in polyimides as a function of relative humidity (RH) was determined by exposing film samples to successively higher RH values ranging from 10 to 85% at 25°C. The isothermal moisture absorption as a function of percent RH was found to be nearly linear for all of the polyimides studied. The effect of moisture on the electrical properties of a BPDA/PPD polyimide was also investigated. The relative dielectric constant at 25 °C was found to be a linear function of the moisture absorbed.

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Effect of Treatment Process on the Structure and Properties of Sr0.48Ba0.24Ca0.28TiO3-Based Varistor Ceramics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.775 ◽

2007 ◽

Vol 336-338 ◽

pp. 775-778

Author(s):

Yu Xing Xu ◽

Zi Long Tang ◽

Zhong Tai Zhang ◽

Li Hai Xu

Keyword(s):

Dielectric Constant ◽

Electrical Properties ◽

Dielectric Loss ◽

Treatment Process ◽

Oxidation Temperature ◽

Structure And Properties ◽

Defect Reactions ◽

Effect Of Treatment

Sr0.48Ba0.24Ca0.28TiO3-based varistor ceramics with an excellent capacitor-varistor multifunctional characteristics (V1mA = 11 ~ 49 ν.mm-1, α = 6.1 ~ 11.3, ε r max=3.5×105, tanδmin = 5%) were prepared using conventional solid method. The effect of oxidation temperature and time on structure and electrical properties were investigated. The results show that with increasing the oxidation temperature from 800°C to 900°C, the varistor voltage V1mA and non-linearity coefficient α defining varistor characteristics increase linearly, while the dielectric constant ε r and dielectric loss tanδ decrease linearly. There exists an optimum α value when the specimens were oxidized at 850°C for 3h. This behavior was explained through various defect reactions of dopants.

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