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71.
Lee Byung-Chul Kim Seon-Byeong Moon Jei-Kwon Park Sang-Yoon 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(1):91-103
Journal of Radioanalytical and Nuclear Chemistry - Complete sets of reaction mechanisms are proposed in the acidic and reductive dissolution of magnetite, nickel ferrite, and chromite using the... 相似文献
72.
C.-B. Moon T. Komatsubara Y. Sasaki T. Jumatsu K. Yamada K. Satou K. Furuno 《The European Physical Journal A - Hadrons and Nuclei》2002,14(1):13-16
Excited states of the 119Xe nucleus have been studied by using in-beam γ-ray spectroscopy with the 107Ag ( 16O, p3n) 119Xe fusion-evaporation reaction at a beam energy of 85 MeV. The level scheme of 119Xe has been derived from γ-γ coincidence and γ-γ angular correlation analyses. We have, for the first time, established the
second negative-parity favored and unfavored states built on the 11/2- state, namely the yrare rotational bands in 119Xe. In contrast to the behavior of the yrast bands where the favored states are lying lower in energy, the yrare favored states
were observed to lie above the unfavored band. Such a signature inversion in 119Xe is changed to be normal at I = 12?.
Received: 8 January 2002 / Accepted: 18 April 2002 相似文献
73.
We present a novel mode filter operating for the 1060-nm band, which selectively removes the power of the high-order mode (HOM) from a conventional single-mode fiber (C-SMF) that supports two modes at the short-wavelength band. Our mode filter is fabricated very easily by fusion-splicing a short section of short-wavelength single-mode fiber in the middle of the C-SMF link. By using our spliced-fiber mode filter (SF-MF), a high HOM suppression performance of > 18 dB has been achieved with a low insertion loss of < 0.3 dB over the full band of optical communications from 1050 nm to 1650 nm. We have also developed a new mode power measurement scheme that takes advantage of the bending sensitivity of the HOM guidance. This measurement scheme enabled us to evaluate accurately the performance factors of the fabricated mode filter. 相似文献
74.
Aeryung Moon 《Journal of Combinatorial Theory, Series B》1984,37(2):173-188
Let G(n, k) denote the graph of the Johnson Scheme J(n, k), i.e., the graph whose vertices are all k-subsets of a fixed n-set, with two vertices adjacent if and only if their intersection is of size k ? 1. It is known that G(n, k) is a distance regular graph with diameter k. Much work has been devoted to the question of whether a distance regular graph with the parameters of G(n, k) must isomorphic to G(n, k). In this paper, this question is settled affirmatively for n ≥ 20. In fact the result is proved with weaker conditions. 相似文献
75.
Suppose one is given two related generating functionsa(x) = a
n
x
n
andb(x) = b
n
x
n
, often it is of interest to determine the limiting behaviour of the quantitiesa
n
/b
n
We survey some earlier results of this nature and give some new ones 相似文献
76.
We obtain various results involving the centroid branches of randomly chosen trees from simply generated families. 相似文献
77.
Young-Joo Eo Wonha Lee Kyunhwan Kim SeJin Ahn Ara Cho Jihye Gwak Kyunghoon Yoon Se Youn Moon Hyo Rim Jung Jin Hyeok Kim Jae Ho Yun 《Current Applied Physics》2014,14(10):1349-1355
Carbon-free CuInSe2 (CIS) thin film with a dense microstructure has been prepared using a novel non-vacuum based fabrication route. CuxSy and In2Se3 binary nanoparticles, approximately 10 nm in size, were synthesized by a low temperature colloidal process. The precursor film was deposited using the coating ink formulated with the binary nanoparticles and pyridine, and then annealed in the rapid thermal annealing (RTA) chamber at 540 °C for 15 min under selenium (Se) atmosphere. Scanning electron micrographs, X-ray diffraction patterns and Raman spectra showed a phase pure carbon-free and dense CIS thin film was prepared in this method. A solar cell device fabricated using this CIS thin film showed the following photovoltaic characteristics: VOC = 350 mV, JSC = 24.72 mA cm−2, FF = 38.73% and η = 3.36% under standard AM 1.5 condition. 相似文献
78.
The free flexural vibration of a hanged clamped-free cylindrical shell with various boundary conditions partially submerged in a fluid is investigated. Specifically, the effects of the boundary conditions such as the existence of the external wall, internal shaft, and bottom on the natural vibration characteristics of the partially submerged cylindrical shell are investigated both theoretically and experimentally. The fluid is assumed to be inviscid and irrotational. The cylindrical shell is modeled by using the Rayleigh–Ritz method based on the Sanders shell theory. The kinetic energy of the fluid is derived by solving a boundary-value problem related to the fluid motion. The theoretical predictions were in good agreement with the experimental results validating the theoretical approach developed in this study. The effects of the external wall, internal shaft, and bottom on the natural vibration characteristics can be neglected when its boundaries are not very close to the shell structure. 相似文献
79.
Hye Jin Lee Eun Ji Nam Jung-Je Woo Seung-Hyeon Moon Jaeyoung Lee 《Current Applied Physics》2012,12(5):1235-1238
The modification of perfluorinated proton exchange membranes (e.g. Nafion) utilizing a layer by layer (LbL) electrostatic assembly of oppositely charged biophilic polymers such as poly-l-lysine as positive layer and dsDNA as a negative layer is developed to protect the interface between the catalyst layer and the membrane in a low temperature fuel cell. Various physicochemical measurements including water uptake, proton conductivity and surface tension were investigated for both the as-received Nafion and the biopolymeric LbL modified Nafion. The smaller water contact angle and the less swelling characteristics of the biopolymer modified Nafion membrane was founded compared to that of as-received Nafion. This clearly indicates that the more hydrophilic surface of biopolymeric layers on Nafion plays an important role in the enhanced dimensional stability. In addition, a potential hypothesis explaining the higher proton conductivity from the LbL biopolymeric film coated Nafion is suggested. 相似文献
80.
Sodium magnetic resonance (MR) imaging is a promising technique for detecting changes of proteoglycan (PG) content in cartilage associated with knee osteoarthritis. Despite its potential clinical benefit, sodium MR imaging in vivo is challenging because of intrinsically low sodium concentration and low MR signal sensitivity. Some of the challenges in sodium MR imaging may be eliminated by the use of a high-sensitivity radiofrequency (RF) coil, specifically, a dual-tuned (DT) proton/sodium RF coil which facilitates the co-registration of sodium and proton MR images and the evaluation of both physiochemical and structural properties of knee cartilage. Nevertheless, implementation of a DT proton/sodium RF coil is technically difficult because of the coupling effect between the coil elements (particularly at high field) and the required compact design with improved coil sensitivity. In this study, we applied a multitransceiver RF coil design to develop a DT proton/sodium coil for knee cartilage imaging at 3 T. With the new design, the size of the coil was minimized, and a high signal-to-noise ratio (SNR) was achieved. DT coil exhibited high levels of reflection S11 (~-21 dB) and transmission coefficient S12 (~-19 dB) for both the proton and sodium coils. High SNR (range 27-38) and contrast-to-noise ratio (CNR) (range 15-21) were achieved in sodium MR imaging of knee cartilage in vivo at 3-mm(3) isotropic resolution. This DT coil performance was comparable to that measured using a sodium-only birdcage coil (SNR of 28 and CNR of 20). Clinical evaluation of the DT coil on four normal subjects demonstrated a consistent acquisition of high-resolution proton images and measurement of relative sodium concentrations of knee cartilages without repositioning of the subjects during the same MR scanning session. 相似文献