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Hee Chul Lee - One of the best experts on this subject based on the ideXlab platform.
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Effects of Zn/Ni Ratio and Doping Material on Piezoelectric Characteristics of Pb((Zn, Ni)1/3Nb2/3)O3–Pb(Zr, Ti)O3 Ceramics
Science of Advanced Materials, 2020Co-Authors: So Won Kim, Yong Jeong Jeong, Hee Chul LeeAbstract:This study investigates the effects of the Zn/Ni composition ratio and Doping Materials on the piezoelectric properties of PZNN-PZT ceramics for the fabrication of piezoelectric ceramics with excellent characteristics. A soft relaxor was used to improve the electrical characteristics and sinterability. The ceramics were fabricated with a base composition ratio of 0.13Pb((Zn1–xNix)1/3Nb2/3)O3–0.87Pb(Zr0.5Ti0.5)O3. The columbite phase was formed by reacting NiO and Nb2O5, which have low reactivity, as the first calcination, and the columbite precursor method was applied for the second calcination with PbO. Although the pellet was produced by sintering at a relatively low temperature of 950 °C, we obtained a dense ceramic with a high density of 7.9 g/cm3 . To improve the quality factor in the composition with a Ni/(Ni + Zn) molar ratio of 0.1, the Doping Materials MnO2, Fe2O3, CuO, and Bi2O3 were added and their properties were confirmed. Pure perovskite phases were formed in the ceramics of all compositions and Doping Materials. In particular, the PZNN-PZT ceramics doped with 0.3 wt% MnO2 showed a piezoelectric coefficient of 348 pC/N, electromechanical coupling factor of 0.59, mechanical quality factor of 345, and Curie temperature of 316 °C, which are excellent piezoelectric characteristics.
So Won Kim - One of the best experts on this subject based on the ideXlab platform.
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Effects of Zn/Ni Ratio and Doping Material on Piezoelectric Characteristics of Pb((Zn, Ni)1/3Nb2/3)O3–Pb(Zr, Ti)O3 Ceramics
Science of Advanced Materials, 2020Co-Authors: So Won Kim, Yong Jeong Jeong, Hee Chul LeeAbstract:This study investigates the effects of the Zn/Ni composition ratio and Doping Materials on the piezoelectric properties of PZNN-PZT ceramics for the fabrication of piezoelectric ceramics with excellent characteristics. A soft relaxor was used to improve the electrical characteristics and sinterability. The ceramics were fabricated with a base composition ratio of 0.13Pb((Zn1–xNix)1/3Nb2/3)O3–0.87Pb(Zr0.5Ti0.5)O3. The columbite phase was formed by reacting NiO and Nb2O5, which have low reactivity, as the first calcination, and the columbite precursor method was applied for the second calcination with PbO. Although the pellet was produced by sintering at a relatively low temperature of 950 °C, we obtained a dense ceramic with a high density of 7.9 g/cm3 . To improve the quality factor in the composition with a Ni/(Ni + Zn) molar ratio of 0.1, the Doping Materials MnO2, Fe2O3, CuO, and Bi2O3 were added and their properties were confirmed. Pure perovskite phases were formed in the ceramics of all compositions and Doping Materials. In particular, the PZNN-PZT ceramics doped with 0.3 wt% MnO2 showed a piezoelectric coefficient of 348 pC/N, electromechanical coupling factor of 0.59, mechanical quality factor of 345, and Curie temperature of 316 °C, which are excellent piezoelectric characteristics.
Yong Jeong Jeong - One of the best experts on this subject based on the ideXlab platform.
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Effects of Zn/Ni Ratio and Doping Material on Piezoelectric Characteristics of Pb((Zn, Ni)1/3Nb2/3)O3–Pb(Zr, Ti)O3 Ceramics
Science of Advanced Materials, 2020Co-Authors: So Won Kim, Yong Jeong Jeong, Hee Chul LeeAbstract:This study investigates the effects of the Zn/Ni composition ratio and Doping Materials on the piezoelectric properties of PZNN-PZT ceramics for the fabrication of piezoelectric ceramics with excellent characteristics. A soft relaxor was used to improve the electrical characteristics and sinterability. The ceramics were fabricated with a base composition ratio of 0.13Pb((Zn1–xNix)1/3Nb2/3)O3–0.87Pb(Zr0.5Ti0.5)O3. The columbite phase was formed by reacting NiO and Nb2O5, which have low reactivity, as the first calcination, and the columbite precursor method was applied for the second calcination with PbO. Although the pellet was produced by sintering at a relatively low temperature of 950 °C, we obtained a dense ceramic with a high density of 7.9 g/cm3 . To improve the quality factor in the composition with a Ni/(Ni + Zn) molar ratio of 0.1, the Doping Materials MnO2, Fe2O3, CuO, and Bi2O3 were added and their properties were confirmed. Pure perovskite phases were formed in the ceramics of all compositions and Doping Materials. In particular, the PZNN-PZT ceramics doped with 0.3 wt% MnO2 showed a piezoelectric coefficient of 348 pC/N, electromechanical coupling factor of 0.59, mechanical quality factor of 345, and Curie temperature of 316 °C, which are excellent piezoelectric characteristics.
Yue Hao - One of the best experts on this subject based on the ideXlab platform.
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high temperature 300 c ald grown al2o3 on hydrogen terminated diamond band offset and electrical properties of the mosfets
Applied Physics Letters, 2020Co-Authors: Zeyang Ren, Jinfeng Zhang, Jincheng Zhang, Chunfu Zhang, Yue HaoAbstract:Hydrogen-terminated diamond (H-diamond) metal-oxide-semiconductor field effect transistors (MOSFETs) were fabricated on a polycrystalline diamond substrate. The device has a gate length of 2 μm and uses Al2O3 grown by atomic layer deposition at 300 °C as a gate dielectric and passivation layer. The Al2O3/H-diamond interfacial band configuration was investigated by X-ray photoelectron spectroscopy, and a large valence band offset (3.28 eV) that is very suitable for p-channel H-diamond FETs was observed. Meanwhile, the measured O/Al ratio hints that there are Oi or VAl defects in the Al2O3 dielectric, which can work as an acceptorlike transfer Doping Material on a H-diamond surface. The device delivers the maximum saturation drain current of over 200 mA/mm, which is the highest for 2-μm H-diamond MOSFETs with the gate dielectric or passivation layer grown at 300 °C or higher temperature. The ultrahigh on/off ratio of 1010 and ultralow gate leakage current of below 10−12 A have been achieved. The high device performance is ascribed to the ultrahigh carrier density, good interface characteristics, and device processes. In addition, the transient drain current response of the device can follow the gate voltage switching on/off pulse at a frequency from 100 kHz to 1 MHz, which indicates the potential of the H-diamond FETs in power switch applications.
Sidik Permana - One of the best experts on this subject based on the ideXlab platform.
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fuel breeding analysis on low moderated fuel ratio based on actinides closed water cooled thorium reactor
Journal of Physics: Conference Series, 2018Co-Authors: Sidik Permana, Syeilendra Pramuditya, Dwi IrwantoAbstract:Utilization of spent nuclear fuel and some fuel breeding capabilities of nuclear fuels to extend the sustainability aspect of nuclear fuel become more important issues to be optimized. Thorium fuel utilization based on water-cooled reactor is one of the possible options to be used and optimized as well as uranium fuel utilization. Some schemes of accumulated spent nuclear fuels can be used as recycled fuel in water-cooled reactor based on thorium fuel. In the present analysis, fuel sustainability aspect of nuclear fuel will be evaluated, which is based on a water-cooled reactor. As a fuel basis, thorium is used with can be mixed with additional recycled spent nuclear fuels. Some minor actinides (MA) as recycled fuels are used as Doping Material to be loaded to the water cooled reactors with thorium fuel as fuel basis and heavy water as moderator and coolant. The evaluation has been made by adopting a computational simulation of an equilibrium burnup analysis method, which was coupled with cell calculation of computer code of SRAC with JENDL.32 as nuclear data library. Several survey parameters have been evaluated to evaluate some effect of MA Doping rate, different moderation ratio and power density levels to the reactor performance including fuel-breeding capability and void reactivity coefficient. Effect of some actinide composition to fuel breeding capability as well as safety aspect, which is based on void reactivity coefficient have been investigated. Fuel breeding capability can be obtained by the present reactor systems; as well as negative void reactivity has been show for more moderator ratio and less power density. Low portion of moderation to fuel ratios (MFR) are used to have a better fuel breeding capability as well as some from contribution from recycled fuel of minor actinides (MA) and less power density. A negative void reactivity can be obtained in this system and it becomes less negative for Doping MA and more power density as well as a positive void reactivity coefficient value for much less moderation ratio.
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Study on Material attractiveness aspect of spent nuclear fuel of LWR and FBR cycles based on isotopic plutonium production
Energy Conversion and Management, 2013Co-Authors: Sidik Permana, Mitsutoshi Suzuki, Novitrian, Masaki Saito, Abdul Waris, Zaki Su’udAbstract:Abstract Recycling minor actinide (MA) as well as used uranium and plutonium can be considered to reduce nuclear waste production as well as to increase the intrinsic aspect of nuclear nonproliferation as Doping Material. Plutonium production as a significant aspect of recycling nuclear fuel option, gives some advantages and challenges, such as fissile Material utilization of plutonium as well as production of some even mass number plutonium. The study intends to evaluate the Material attractiveness based on the intrinsic feature of Material barrier such as plutonium composition, decay heat and spontaneous fission neutron components from spent fuel (SF) light water reactor (LWR) and fast breeder reactor (FBR) cycles. A significant contribution has been shown by decay heat (DH) and spontaneous fission neutron (SFN) of even mass number of plutonium isotopes to the total DH and SFN of plutonium element, in particular from isotopic plutonium Pu-238 and Pu-240 contributions. Longer decay cooling time and higher burnup are effective to increase the Material barrier (DH and SFN) level from reactor grade plutonium level to MOX grade plutonium level. Material barrier of plutonium element from spent fuel (SF) FBR in the core regions has similarity to the Material barrier profile of SF LWR which can be categorized as MOX fuel grade plutonium. Plutonium compositions, DH and SFN components are categorized as weapon grade plutonium level for FBR blanket regions with no Doping minor actinide (MA) case. Doping MA in the FBR blanket regions is effective to increase the Material barrier level from weapon grade plutonium to MOX fuel or more grade level. Moreover, increasing Material barrier of plutonium isotopes can be achieved effectively by increasing Pu-238 production as main contributor for LWR and FBR core regions, and from converted MA in the FBR blanket which affects directly to increase DH and SFN components.