An investigation of dielectric breakdown on a pressurized, flowing oil switch - WITHDRAWN

2009 ◽  
Author(s):  
◽  
Peter A. Norgard
Keyword(s):  
Electric Field ◽  
Rise Time ◽  
High Performance ◽  
Dielectric Breakdown ◽  
High Energy ◽  
Operating Characteristics ◽  
University Of Missouri ◽  
Breakdown Electric Field ◽  
Alpha Olefin ◽  
Oil Flow

WITHDRAWN - [ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] In the not-so-distant future, a need is foreseen for a high-performance, compact switch that is capable of repetitively switching kilovolts to megavolts and several hundred joules, all while delivering a square pulse with a fast current rise time. Many industrial and military applications currently exist that could take advantage of these operating characteristics, and many more are surely to be developed in the coming years. The proposed approach to realizing the goal of producing a fast rise time, high voltage, high energy, repetitive switch technology is to employ a pressurized, flowing oil dielectric switching medium. Oil pressure and oil flow will be used to increase the rate of dielectric recovery following a high energy discharge, thus enabling a much higher operating repetition frequency; oil pressure will be utilized to control gaseous switching byproducts, and oil flow will be utilized to control solid and gaseous switching byproducts. The well-known increase in breakdown electric field strength with increasing oil pressure will be utilized to reduce the gap separation, thus reducing the inductance of the electrical arc and increasing the rise time of the current pulse produced during breakdown. An experiment was designed and undertaken to evaluate the complete statistical performance of the breakdown electric field of an emerging dielectric liquid, poly-[alpha]olefin, with respect to variations in oil pressure, oil flow rate, peak rate of rise of the voltage, and gap separation.

scholarly journals Improved dielectric constant and energy density of P(VDF-HFP) composites using NBT-xST (x=0, 0.10, 0.26) whiskers

2018 ◽  
Vol 08 (06) ◽  
pp. 1850040 ◽  
Author(s):  
Xuefan Zhou ◽  
Lu Wang ◽  
Guoliang Xue ◽  
Kechao Zhou ◽  
Hang Luo ◽  
...  
Keyword(s):  
Energy Efficiency ◽  
Dielectric Constant ◽  
Energy Storage ◽  
Energy Density ◽  
Electric Field ◽  
High Performance ◽  
Volume Fraction ◽  
High Energy ◽  
High Energy Density ◽  
Surface Modified

The high-performance energy-storage dielectric capacitors are increasingly important due to their wide applications in high power electronics. Here, we fabricated a novel P(VDF-HFP)-based capacitor with surface-modified NBT-[Formula: see text]ST ([Formula: see text], 0.10, 0.26) whiskers, denoted as Dop@NBT-[Formula: see text]ST/P(VDF-HFP). The influences of ST content, fillers’ volume fraction and electric field on the dielectric properties and energy-storage performance of the composites were investigated systematically. The results show that the dielectric constant monotonously increased with the increase of ST content and fillers’ volume fraction. The composite containing 10.0 vol% NBT-0.26ST whiskers possessed a dielectric constant of 39 at 1[Formula: see text]kHz, which was 5.6 times higher than that of pure P(VDF-HFP). It was noticed that the D-E loops of the composites became thinner and thinner with the increase of ST content. Due to the reduced remnant polarization, the composite with 5.0 vol% NBT-0.26ST whiskers achieved a high energy density of 6.18[Formula: see text]J/cm3 and energy efficiency of approximately 57% at a relatively low electric field of 200[Formula: see text]kV/mm. This work indicated that NBT-0.26ST whisker is a kind of potential ceramic filler in fabricating the dielectric capacitor with high discharged energy density and energy efficiency.

scholarly journals Simulation and Analysis of Microring Electric Field Sensor Based on a Lithium Niobate-on-Insulator

Crystals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 359
Author(s):  
Zhenlin Wu ◽  
Yumeng Lin ◽  
Shaoshuai Han ◽  
Xiong Yin ◽  
Menghan Ding ◽  
...  
Keyword(s):  
Finite Difference ◽  
Lithium Niobate ◽  
Electric Field ◽  
High Performance ◽  
Transmission Loss ◽  
High Energy ◽  
Microring Resonator ◽  
Material System ◽  
Electric Field Sensor ◽  
Field Sensor

With the increasing sensitivity and accuracy of contemporary high-performance electronic information systems to electromagnetic energy, they are also very vulnerable to be damaged by high-energy electromagnetic fields. In this work, an all-dielectric electromagnetic field sensor is proposed based on a microring resonator structure. The sensor is designed to work at 35 GHz RF field using a lithium niobate-on-insulator (LNOI) material system. The 2.5-D variational finite difference time domain (varFDTD) and finite difference eigenmode (FDE) methods are utilized to analyze the single-mode condition, bending loss, as well as the transmission loss to achieve optimized waveguide dimensions. In order to obtain higher sensitivity, the quality factor (Q-factor) of the microring resonator is optimized to be 106 with the total ring circumference of 3766.59 μm. The lithium niobate layer is adopted in z-cut direction to utilize TM mode in the proposed all-dielectric electric field sensor, and with the help of the periodically poled lithium niobate (PPLN) technology, the electro-optic (EO) tunability of the device is enhanced to 48 pm·μm/V.

Modification of Deposition Process of Piezoelectric Polycrystalline Film by Hydrothermal Method -Improvement of the Deposition Process by Pre-Treatment Using Hydrogen Peroxide

2005 ◽  
Vol 872 ◽  
Author(s):  
Akito Endo ◽  
Norimichi Kawashima ◽  
Shinichi Takeuchi ◽  
Mutsuo Ishikawa ◽  
Minoru Kurosawa
Keyword(s):  
Hydrogen Peroxide ◽  
Electric Field ◽  
Thick Film ◽  
Dielectric Breakdown ◽  
Deposition Process ◽  
High Reactivity ◽  
Polycrystalline Film ◽  
Hydrophilic Property ◽  
Breakdown Electric Field ◽  
Pre Treatment

AbstractWe have studied on hydro-thermally synthesis of Pb(Ti, Zr)O3(PZT)piezoelectric polycrystalline thick film on titanium (Ti) substrate. The purpose of this study is resolving the problems for application of PZT hydrothermal polycrystalline thick film to the ultra miniature high frequency medical ultrasound array probe. The problems were the existence of pinholes in the deposited PZT film, the rough surface of that, low dielectric breakdown electric field etc. The surface of Ti substrate was pretreated to have hydrophilic property by using high reactivity of hydrogen peroxide for resolving the problems in this study. As results, hydrophilic property on the surface of Ti substrate was improved. Surface of PZT hydrothermal polycrystalline thick film without pinholes and smooth surface of that were obtained. Furthermore, the material properties like density, Young's modulus and piezoelectric constant d31 were increased by the pretreatment of Ti substrate. Consequently, dielectric breakdown electric field of PZT hydrothermal polycrystalline film was improved.

High energy density in PVDF nanocomposites using an optimized nanowire array

2018 ◽  
Vol 20 (26) ◽  
pp. 18031-18037 ◽  
Author(s):  
Ru Guo ◽  
Hang Luo ◽  
Weiwei Liu ◽  
Xuefan Zhou ◽  
Lin Tang ◽  
...  
Keyword(s):  
Energy Density ◽  
Electric Field ◽  
Coating Layer ◽  
Nanowire Array ◽  
High Energy ◽  
Nanowire Arrays ◽  
High Energy Density ◽  
High Permittivity ◽  
Breakdown Electric Field ◽  
Discharged Energy Density

Introducing PZT as the coating layer of TiO2 nanowire arrays, the obtained TiO2-P/PVDF nanocomposite achieved a high permittivity and breakdown electric field of 53 at 1 kHz and 550 kV mm−1, respectively, resulting in a higher discharged energy density of 12.4 J cm−3.

scholarly journals USING A RE-ENTRANT MICROWAVE RESONATOR TO MEASURE AND MODEL THE DIELECTRIC BREAKDOWN ELECTRIC FIELD OF GASES

2009 ◽  
Vol 15 ◽  
pp. 175-195 ◽  
Author(s):  
Stephen K. Remillard ◽  
Alejandro Hardaway ◽  
B. Mork ◽  
Jake Gilliland ◽  
Joseph Gibbs
Keyword(s):  
Electric Field ◽  
Dielectric Breakdown ◽  
Microwave Resonator ◽  
Breakdown Electric Field

Efficient Co-Harvesting of Solar Energy and Low-Grade Heat by Molecular Photoswitches for High Energy Density, Long-Term Stable Solar Thermal Battery

2019 ◽  
Author(s):  
Zhao-Yang Zhang ◽  
Tao LI
Keyword(s):  
Energy Density ◽  
Solar Energy ◽  
High Performance ◽  
High Energy ◽  
Solar Thermal ◽  
High Energy Density ◽  
Low Grade ◽  
Thermal Battery ◽  
Low Grade Heat

Solar energy and ambient heat are two inexhaustible energy sources for addressing the global challenge of energy and sustainability. Solar thermal battery based on molecular switches that can store solar energy and release it as heat has recently attracted great interest, but its development is severely limited by both low energy density and short storage stability. On the other hand, the efficient recovery and upgrading of low-grade heat, especially that of the ambient heat, has been a great challenge. Here we report that solar energy and ambient heat can be simultaneously harvested and stored, which is enabled by room-temperature photochemical crystal-to-liquid transitions of small-molecule photoswitches. The two forms of energy are released together to produce high-temperature heat during the reverse photochemical phase change. This strategy, combined with molecular design, provides high energy density of 320-370 J/g and long-term storage stability (half-life of about 3 months). On this basis, we fabricate high-performance, flexible film devices of solar thermal battery, which can be readily recharged at room temperature with good cycling ability, show fast rate of heat release, and produce high-temperature heat that is >20<sup> o</sup>C higher than the ambient temperature. Our work opens up a new avenue to harvest ambient heat, and demonstrate a feasible strategy to develop high-performance solar thermal battery.

Efficient Co-Harvesting of Solar Energy and Low-Grade Heat by Molecular Photoswitches for High Energy Density, Long-Term Stable Solar Thermal Battery

2019 ◽  
Author(s):  
Zhao-Yang Zhang ◽  
Tao LI
Keyword(s):  
Energy Density ◽  
Solar Energy ◽  
High Performance ◽  
High Energy ◽  
Solar Thermal ◽  
High Energy Density ◽  
Low Grade ◽  
Thermal Battery ◽  
Low Grade Heat

Solar energy and ambient heat are two inexhaustible energy sources for addressing the global challenge of energy and sustainability. Solar thermal battery based on molecular switches that can store solar energy and release it as heat has recently attracted great interest, but its development is severely limited by both low energy density and short storage stability. On the other hand, the efficient recovery and upgrading of low-grade heat, especially that of the ambient heat, has been a great challenge. Here we report that solar energy and ambient heat can be simultaneously harvested and stored, which is enabled by room-temperature photochemical crystal-to-liquid transitions of small-molecule photoswitches. The two forms of energy are released together to produce high-temperature heat during the reverse photochemical phase change. This strategy, combined with molecular design, provides high energy density of 320-370 J/g and long-term storage stability (half-life of about 3 months). On this basis, we fabricate high-performance, flexible film devices of solar thermal battery, which can be readily recharged at room temperature with good cycling ability, show fast rate of heat release, and produce high-temperature heat that is >20<sup> o</sup>C higher than the ambient temperature. Our work opens up a new avenue to harvest ambient heat, and demonstrate a feasible strategy to develop high-performance solar thermal battery.

Photodiodes based on MAPbBr3/Bi3+ doped MAPbCl3 single crystals heterojunction for X-ray detection

CrystEngComm ◽  
2021 ◽  
Author(s):  
Yuzhu Pan ◽  
Xin Wang ◽  
Jingda Zhao ◽  
Yubing Xu ◽  
Yuwei Li ◽  
...  
Keyword(s):  
Electric Field ◽  
Single Crystals ◽  
External Electric Field ◽  
High Performance ◽  
X Ray

Perovskites single crystals (PSCs) could be used to made high performance photoelectric detectors due to its superior optoelectronic characteristics. Generally, external electric field need to be applied in the PSCs-based...

scholarly journals Defect-induced B4C electrodes for high energy density supercapacitor devices

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Özge Balcı ◽  
Merve Buldu ◽  
Ameen Uddin Ammar ◽  
Kamil Kiraz ◽  
Mehmet Somer ◽  
...  
Keyword(s):  
Active Carbon ◽  
High Performance ◽  
Carbon Sources ◽  
High Energy ◽  
High Energy Density ◽  
Synthesis Conditions ◽  
High Energy Ball Mill ◽  
Energy Ball ◽  
G Ratio ◽  
Energy And Power Density

AbstractBoron carbide powders were synthesized by mechanically activated annealing process using anhydrous boron oxide (B2O3) and varying carbon (C) sources such as graphite and activated carbon: The precursors were mechanically activated for different times in a high energy ball mill and reacted in an induction furnace. According to the Raman analyses of the carbon sources, the I(D)/I(G) ratio increased from ~ 0.25 to ~ 0.99, as the carbon material changed from graphite to active carbon, indicating the highly defected and disordered structure of active carbon. Complementary advanced EPR analysis of defect centers in B4C revealed that the intrinsic defects play a major role in the electrochemical performance of the supercapacitor device once they have an electrode component made of bare B4C. Depending on the starting material and synthesis conditions the conductivity, energy, and power density, as well as capacity, can be controlled hence high-performance supercapacitor devices can be produced.

scholarly journals Recent Advances in the Synthesis of Polymer-Grafted Low-K and High-K Nanoparticles for Dielectric and Electronic Applications

Molecules ◽  
2021 ◽  
Vol 26 (10) ◽  
pp. 2942
Author(s):  
Bhausaheb V. Tawade ◽  
Ikeoluwa E. Apata ◽  
Nihar Pradhan ◽  
Alamgir Karim ◽  
Dharmaraj Raghavan
Keyword(s):  
Energy Density ◽  
Polymer Nanocomposites ◽  
High Performance ◽  
Breakdown Strength ◽  
Polymer Nanocomposite ◽  
High Energy ◽  
Polymer Chains ◽  
High Energy Density ◽  
Grafted Nanoparticles ◽  
Grafting From

The synthesis of polymer-grafted nanoparticles (PGNPs) or hairy nanoparticles (HNPs) by tethering of polymer chains to the surface of nanoparticles is an important technique to obtain nanostructured hybrid materials that have been widely used in the formulation of advanced polymer nanocomposites. Ceramic-based polymer nanocomposites integrate key attributes of polymer and ceramic nanomaterial to improve the dielectric properties such as breakdown strength, energy density and dielectric loss. This review describes the ”grafting from” and ”grafting to” approaches commonly adopted to graft polymer chains on NPs pertaining to nano-dielectrics. The article also covers various surface initiated controlled radical polymerization techniques, along with templated approaches for grafting of polymer chains onto SiO2, TiO2, BaTiO3, and Al2O3 nanomaterials. As a look towards applications, an outlook on high-performance polymer nanocomposite capacitors for the design of high energy density pulsed power thin-film capacitors is also presented.

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