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111.
Dong-Jin Kim Hong Pyo Kim Seong Sik Hwang Joung Soo Kim Jangyul Park 《Metals and Materials International》2010,16(2):259-266
The stress corrosion cracking (SCC) behavior of Alloy 600 was studied in aqueous solutions containing lead. Electrochemical
polarization and current transient experiments were performed at 315 °C in a 40% sodium hydroxide solution to assess the effect
of lead on a passive film formed on Alloy 600. The influences of the alloy microstructure and the addition of an inhibitor
to the environments on lead-induced SCC were investigated using C-ring and slow strain-rate tensile (SSRT) tests in demineralized
high-purity water and caustic solutions containing PbO at 315 °C. The surface films on Alloy 600 were examined using Auger
electron spectroscopy (AES) and energy dispersive x-ray spectroscopy (EDXS). The PbO markedly accelerated SCC of Alloy 600
in the caustic solution and the high-purity water at 315 °C. The addition of nickel boride (NiB) or cerium boride (CeB6) to the test solutions decreased the susceptibility of Alloy 600 to SCC. Thermally treated Alloy 600 (Alloy 600 TT) tended
to crack in a transgranular mode, while the solution-annealed Alloy 600 (Alloy 600 SA) tended to crack in an intergranular
mode in water containing PbO. 相似文献
112.
Yong Il Park Jeong Hyun Kim Kang Taek Lee Ki‐Seok Jeon Hyon Bin Na Jung Ho Yu Hyung Min Kim Nohyun Lee Seung Hong Choi Sung‐Il Baik Hyoungsu Kim Seung Pyo Park Beom‐Jin Park Young Woon Kim Sung Ho Lee Soo‐Young Yoon In Chan Song Woo Kyung Moon Yung Doug Suh Taeghwan Hyeon 《Advanced materials (Deerfield Beach, Fla.)》2009,21(44):4467-4471
113.
Trung‐Kien Nguyen Viet‐Hoang Le Quoc‐Hoang Duong Seok‐Kyun Han Sang‐Gug Lee Nak‐Seon Seong Nae‐Soo Kim Cheol‐Sig Pyo 《ETRI Journal》2008,30(1):33-46
This paper presents the experimental results of a low‐power low‐cost RF transceiver for the 915 MHz band IEEE 802.15.4b standard. Low power and low cost are achieved by optimizing the transceiver architecture and circuit design techniques. The proposed transceiver shares the analog baseband section for both receive and transmit modes to reduce the silicon area. The RF transceiver consumes 11.2 mA in receive mode and 22.5 mA in transmit mode under a supply voltage of 1.8 V, in which 5 mA of quadrature voltage controlled oscillator is included. The proposed transceiver is implemented in a 0.18 μm CMOS process and occupies 10 mm2 of silicon area. 相似文献
114.
115.
Areum Kim Seon Jea Lee Eunmi Choi Sung Gyu Pyo 《Metals and Materials International》2014,20(4):775-783
Selective deposition and formation of Ni-Cu-Sn electrodes by electroless plating using an all-wet process were investigated to find a substitute for the commercial solar cells made by screen-printed Ag electrodes. Because of Ni-Cu-Sn multilayer, it is necessary to improve contact resistance at each interface using annealing process. So Nickel silicide was created by controlling the Si and Ni interface for the formation of an ohmic contact to reduce the contact resistance and improve the efficiency of solar cells. The phase transition and thermal stability of nickel silicide were analyzed in the annealing temperature range of 200–500 °C. Using electroless plated Ni, films with the thickness of 200±50 nm corresponding to the silicide phases of Ni2Si, Ni3Si2, and NiSi were identified from the thermal budget. The formation of the Ni74-Si26 silicide phase by rapid thermal processing at 250 °C was verified, and the possibility of low-temperature Ni silicidation was identified. 相似文献
116.
117.
Keyhole‐3D phase contrast magnetic resonance angiography: A time‐resolved reconstruction method
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Dong‐Hoon Lee Cheol‐Pyo Hong Man‐Woo Lee Bong‐Soo Han 《International journal of imaging systems and technology》2014,24(1):1-7
In this study, we studied the keyhole imaging technique to 3D Phase‐contrast magnetic resonance angiography (PC MRA) to improve its temporal resolution. Previously, our research group has already studied the 2D PC MRA combined with keyhole technique, and evaluated the applicability. For keyhole‐3D PC MRA, the keyhole factor was used from 12.5% to 50% of the full k‐space. With keyhole factors above 50%, the images were similar to the original image and the vessels in the brain were well observed. We believe the keyhole‐3D PC MRA will give some advantages for improving the temporal resolution of MR systems. 相似文献
118.
119.
SM Pyo SI Kim TJ Shin HK Park M Ree KH Park JS Kang 《Canadian Metallurgical Quarterly》1998,31(15):4777-4781
5,5'-Bis(4-aminophenyl)-2,2'-bifuryl (PFDA) with a well-defined conjugation length was synthesized, and its soluble poly(amic acid) was prepared by polycondensation with pyromellitic dianhydride (PMDA). The PMDA-PFDA polyimide films were obtained from the poly(amic acid) solution through a conventional spin-casting, baking, and thermal imidization process. The PFDA monomer exhibits intense blue photoluminescence with a maximum at 442 nm in a high quantum yield of 0.92, whereas its polyimide film also emits intense blue photoluminescence with double peak maxima at 419 and 436 nm. The polyimide is insoluble in common organic solvents and thermally stable up to 370 degreesC. Overall, the PMDA-PFDA polyimide can be considered to be a potential candidate material for fabricating optoelectronic devices that emit blue light. 相似文献
120.
Major histocompatibility complex-specific prolongation of murine skin and cardiac allograft survival after in vivo depletion of V beta+ T cells 总被引:1,自引:0,他引:1
The preferential usage of certain T cell receptor (TCR) V beta genes has been well established in several major histocompatibility complex (MHC)-restricted immune responses. However, V beta usage among allogeneic responses remains unclear. Because recent findings of ours and others indicate that V beta 8 predominates in certain Ld-restricted, peptide-specific responses, we examined the V beta 8 usage in allogeneic responses to Ld. To selectively recognize the Ld molecule, cells from BALB/c-H-2dm2 (dm2), the Ld-loss mutant mouse, were stimulated in vitro or in vivo with wild-type BALB/c cells. We report here that after the intraperitoneal administration of the anti-V beta 8 monoclonal antibody (mAb) F23.1, peripheral V beta 8 T cells were depleted from dm2 mice. This in vivo depletion abrogated the ability of dm2 splenocytes to mount a primary response to Ld molecules. This abrogation was specific, since the response of V beta 8-depleted dm2 cells to Kb/Db antigens was the same as that of control nondepleted dm2 cells. Furthermore, in vivo depletion of V beta 8 cells was found to cause a dramatic prolongation of Ld-disparate skin grafts (mean survival time [MST] 22.1 +/- 2.1 vs. 10.3 +/- 1.1 d for saline-treated controls, or 10.9 +/- 1.7 d for controls treated with mAb KJ23 to V beta 17). By contrast, V beta 8 depletion had no effect on recipients grafted with haplotype-mismatched skin or single Dk-locus-disparate skin. These findings demonstrate that V beta 8+ T cells predominate in allogeneic response to Ld but not other alloantigens. The effect of V beta 8 depletion was found to be even more dramatic on recipients grafted with Ld-disparate vascularized heart transplants (MST > 100 vs. 8.6 +/- 0.5 d for controls). In total, these findings establish the efficacy of using mAb to the V beta gene family to specifically and significantly enhance the survival of allografts. The implications of detecting V beta 8 usage in both alloreactive or MHC-restricted TCR responses to the same class I molecule are discussed. 相似文献