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排序方式: 共有499条查询结果,搜索用时 31 毫秒
91.
S.-Y. Jeon M.-B. Choi H.-N. Im J.-H. Hwang S.-J. Song 《Journal of Physics and Chemistry of Solids》2012,73(5):656-660
The ionic conduction properties of La2NiO4+δ were studied from oxygen permeation flux and defect-related transport properties. The effects of the applied oxygen chemical potential gradient and temperature on the oxygen permeability of La2NiO4+δ at various thickness are reported. The thermally activated oxygen permeation flux increased monotonically with increasing oxygen chemical potential gradient, yielding a maximum of 0.15 cc min?1 cm?2 under air/N2 conditions for the 0.95 mm-thick La2NiO4+δ specimen at 900 °C. The oxygen ion conductivity of La2NiO4+δ was calculated as a function of temperature and oxygen partial pressure by differentiating the chemical diffusion equation for the oxygen permeation flux based on the dominant electronic transference number. In addition, the oxygen ion conductivity was extracted successfully by solving the Nernst–Einstein equation combining with the calculated self-diffusion coefficient of oxygen from the chemical diffusivity and thermodynamic enhancement factor from the equilibrium oxygen nonstoichoimetry of a La2NiO4+δ specimen, and a deviation of the OPP dependence of 1/6 power was observed. 相似文献
92.
We report on the fabrication of a transparent photostable cell circuit composed of drive and resistor diodes which are face‐to‐face connected to each other with different device area. The diodes consisted of e‐beam evaporated p‐NiO on sputter‐deposited n‐ZnO for p/n diode formation on indium‐tin‐oxide glass. Our transparent diodes show photostable rectifying behavior, about 103 on/off current ratio and even dynamic rectification at a maximum frequency of 100 Hz AC input signal in ambient light. The noticeable photo‐responsivity of the circuit was obtained only under ultraviolet (UV) light. We conclude that our transparent diode circuit is promising in enriching the field of transparent device electronics. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
93.
The properties of nuclei belonging to the newly observed α-decay chain starting from 265Bh have been studied. The axially deformed relativistic mean-field calculation with the force NL-Z2 has been performed in the blockedBCS approximation. Some ground state properties such as binding energies, deformations, spins, and parities, as well as Q-values of the α-decay for this decay chain have been calculated and compared with known experimental data. Good agreement is found. The single-particle spectrum of the nucleus 265 Bh is studied and some new magic numbers are found,while the magnitudes of the shell gaps in superheavy nuclei are much smaller than those of nuclei before the actinium region, and the Fermi surfaces are close to the continuum. Thus the superheavy nuclei are usually not stable. The The methods which give good agreement with the data are selected. 相似文献
94.
关于BL-代数的模糊滤子与模糊理想 总被引:3,自引:1,他引:2
在BL-代数中引入模糊超滤子和模糊固执滤子的概念,证明了如下条件对于BL-代数的非常数模糊滤子f来说是等价的:(1)f是布尔的和素的,(2)f是蕴涵的和素的,(3)f是超的,(4)f是固执的。应用模糊正蕴涵滤子给出G-代数的若干特征性质。提出BL-代数模糊理想的概念,给出一些重要例子,并通过例子说明在BL-代数中模糊理想一般不能由模糊滤子导出。同时,从模糊理想出发构造了商BL-代数,并建立了相应的同态基本定理。最后,研究了BL-代数的几类模糊理想及其相互关系,给出模糊布尔理想、模糊素理想、模糊超理想的特征性质。 相似文献
95.
Han Chung-Hun Hong Jeong Woo Im Hee-Jung 《Journal of Radioanalytical and Nuclear Chemistry》2021,328(2):563-568
Journal of Radioanalytical and Nuclear Chemistry - The efficiency transfer procedure from a geometry where a volume source was placed directly on the endcap of a germanium detector to three... 相似文献
96.
Reflection high-energy electron diffraction, atomic force microscopy, transmission electron microscopy, and double-crystal X-ray curves showed that high-quality InAs quantum dot (QD) arrays inserted into GaAs barriers were embedded in an Al0.3Ga0.7As/GaAs heterostructure. The temperature-dependent photoluminescence (PL) spectra of the InAs/GaAs QDs showed that the exciton peak corresponding interband transition from the ground electronic subband to the ground heavy-hole subband (E1-HH1) was dominantly observed and that the peak position and the full width at half maximum corresponding to the interband transitions of the PL spectrum were dependent on the temperature. The activation energy of the electrons confined in the InAs/GaAs QDs was 115 meV. The electronic subband energy and the energy wave function of the Al0.3Ga0.7As/GaAs heterostructures were calculated by using a self-consistent method. The electronic subband energies in the InAs/GaAs QDs were calculated by using a three-dimensional spatial plane wave method, and the value of the calculated (E1-HH1) transition in the InAs/GaAs QDs was in reasonable agreement with that obtained from the PL measurement. 相似文献
97.
Effect of Si in reactively sputtered Ti-Si-N films on structure and diffusion barrier performance 总被引:2,自引:0,他引:2
X. Sun E. Kolawa S. Im C. Garland M.-A. Nicolet 《Applied Physics A: Materials Science & Processing》1997,65(1):43-45
34 Si23N43 (b3) and Ti35Si13N52 (c3), are synthesized by reactively sputtering a Ti5Si3 or a Ti3Si target, respectively. The silicon-lean film (c3) has a columnar structure closely resembling that of TiN. As a diffusion
barrier between a shallow Si n+p junction diode and a Cu overlayer, this material is effective up to 700 °C for 30 min annealing in vacuum, a performance
similar to that for TiN. The silicon-rich (b3) film contains nanocrystals of TiN, randomly oriented and embedded in an amorphous
matrix. A film of (b3) maintains the stability of the same diode structure up to 850 °C for 30 min in vacuum. This film (b3)
is clearly superior to TiN or to (c3). Similar experiments performed with Al instead of Cu overlayers highlight the importance
of the thermodynamic stability of a barrier layer and demonstrate convincingly that for stable barriers the microstructure
is a parameter that directly determines the barrier performance.
Received: 18 November 1996/Accepted: 22 January 1997 相似文献
98.
We have evaluated thermal stability and aging property of a blue color-emitting phosphor, CaAl2Si2O8:Eu2+ (CAS:Eu2+), synthesized by conventional solid-state reaction method. When both CAS:Eu2+ and BaMgAl10O19:Eu2+ (BAM) were baked in air at 500 °C for 20 min, the decrease of photoluminescence (PL) intensity of CAS:Eu2+ was lower than that of BAM. The aging property of CAS:Eu2+ was also better than that of BAM. Due to its rigid structure and unlimited framework of silicon-oxygen and aluminum-oxygen around Eu2+ ions, Eu2+ ions were protected from outer oxidizing atmosphere and plasma discharge. After analysis of aging property and thermal stability, the differences of these thermal stability and aging property of CAS:Eu2+ from those of BAM were ascribed to its crystal structure which plays a role of a shield for Eu2+ ions against oxidation atmosphere and Xe ion bombardment. 相似文献
99.
Approximate fibrations form a useful class of maps. By definition fibrators provide instant detection of maps in this class, and PL fibrators do the same in the PL category. This paper formalizes a natural concept of partial asphericity and establishes fibrator properties of certain partially aspherical closed manifolds. One consequence is that any connected sum of aspherical PL manifolds with residually finite fundamental groups is a codimension-(2n−2) PL fibrator. 相似文献
100.
Hee-Jung Im Carl Willis Suree Saengkerdsub Rajev Makote Michelle D. Pawel Sheng Dai 《Journal of Sol-Gel Science and Technology》2004,32(1-3):117-123
Solid-state scintillating materials were synthesized by the co-doping of sol–gel components with neutron absorbers [6Li and 10B], organic fluorescence sensitizers such as salicylic acid and 2,5-diphenyloxazole (PPO) and activator 1,4-bis-2-(5-phenyloxazolyl)-benzene (POPOP). The room-temperature sol–gel process through the addition of organic polymers is the key to the successful entrapment of the organic sensitizers and activator in inorganic matrixes. These transparent or translucent sol–gel scintillators were evaluated for alpha radiation and neutron detections. 相似文献