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51.
Kihara Ken; Yagi Yoshihiko; Takeda Yuji; Kawahara Jun I. 《Canadian Metallurgical Quarterly》2011,37(1):168
When two targets (T1 and T2) are embedded in rapid serial visual presentation (RSVP), T2 is often missed (attentional blink, AB) if T2 follows T1 by less than 500 ms. Some have proposed that inhibition of a distractor following T1 contributes to the AB, but no direct evidence supports this proposal. This study examined distractor inhibition by assessing a distractor devaluation effect where inhibited items were evaluated less positively than controls. Experiments 1 and 2 showed that a distractor presented just after T1 was evaluated less favorably when T2 was misidentified, independently of stimulus characteristics. Experiment 3 produced distractor devaluation in T2 incorrect trials when the evaluated distractor was the second item after T1. In contrast, a distractor presented before T1 was not devaluated (Experiment 4). Experiment 5 demonstrated that participants could not recognize presented distractors after an RSVP task, rejecting the possibility that memorized distractors were devalued. Results show a relationship between the devaluation of distractors following T1 and the AB, providing the first direct evidence of the distractor inhibition during the AB. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
Hiromi Odaka Masataka Yamada Ryohei Sakuma Cuie Ding Eiji Kaneko Satoru Yanabu 《Electrical Engineering in Japan》2007,161(1):17-25
A high‐speed vacuum circuit breaker (HSVCB) has been investigated. HSVCB makes high‐frequency current superimposed on a fault current so that the current is forced to be zero and is interrupted. Its interruption performance is considered to be dependent on the rate of change of the current (di/dt). As a fundamental research, we investigated the di/dt– dv/dt characteristics and the insulation recovery characteristic after interrupting the counter‐pulse current for various contact materials of AgWC, CuW, and CuCr. The results revealed that the case where the gap length is larger is better in a current interruption performance. Moreover, it was found that di/dt is not dependent on the insulation recovery characteristics, but the magnitude of interruption current is of great influence. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 161(1): 17– 25, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20362 相似文献
53.
Yoshida Y. Sasaki M. Shibata K. Kawazu Z. Ono K.-I. Nishiguchi H. Yagi T. Nishimura T. 《Quantum Electronics, IEEE Journal of》2005,41(6):828-832
We analyze kink and power saturation phenomena of high power 660-nm laser diodes for DVD-R/RW experimentally. Power-current (P-I) and voltage-current (V-I) characteristics of laser diodes with different cavity lengths were measured. Using these results and thermal resistances, temperature rises caused by self-heating (/spl Delta/T) and the dependence of slope efficiencies on the temperature rise (Se-/spl Delta/T) were calculated. The slope efficiencies decreased linearly with /spl Delta/T and their gradients showed the same value regardless of the cavity length, while they had no systematic dependence on the current. The kinks occurred at the same /spl Delta/T of 30/spl deg/C regardless of the cavity length, while they occurred at different currents. These results indicate that the temperature rise caused by the self-heating is a key parameter for the kink and the saturation power. A method is proposed to calculate the kink and the saturation power using the gradient (Se-/spl Delta/T) and the kink temperature. 相似文献
54.
Broadband four-wave mixing generation in short optical fibres 总被引:1,自引:0,他引:1
Aso O. Shin-Ichi Arai Yagi T. Tadakuma M. Suzuki Y. Namiki S. 《Electronics letters》2000,36(8):709-711
Several advantages of using a short length of fibre to generate broadband four-wave mixing are proposed and verified using wavelength conversion experiments for different lengths of a previously developed high-nonlinearity fibre with a nonlinear coefficient of 13.8 W-1 km-1. Consequently, 91.3 nm broadband simultaneous wavelength conversion is demonstrated using a 100 m long section of the developed fibre 相似文献
55.
We investigated slip and unstable flow phenomena of polystyrene melts in capillaries from the view of the effects of temperature and molecular weight by using three polystyrene samples with different molecular weights (Mw = 192,000, Mw = 258,000, and Mw = 321,000). The slip velocities are estimated by the Mooney method and the modified Mooney method. We found that the slip velocity increases and the critical slip stress above which a slip starts to occur decreases with the temperature. We also observed the melt-fracture at above a critical melt-fracture stress higher than . We found that the onset of melt fracture is affected by the extensional stress near the entry region to the capillary in the barrel and the melt-fracture tends to easily occur with increase of the molecular weight, but is not sensitive to the temperature. 相似文献
56.
Effects of rice straw returning methods on N<Subscript>2</Subscript>O emission during wheat-growing season 总被引:1,自引:0,他引:1
Erdeng Ma Guangbin Zhang Jing Ma Hua Xu Zucong Cai Kazuyuki Yagi 《Nutrient Cycling in Agroecosystems》2010,88(3):463-469
A field experiment was conducted in Jurong of Nanjing, Jiangsu Province, China from 2006 to 2008 to investigate N2O emission during the wheat-growing season as affected by various rice straw returning methods prior to wheat cultivation.
The study was designed to have four treatments: no rice straw applied (CK), rice straw burnt in situ (RB), rice straw evenly
incorporated into the topsoil (RI), rice straw evenly spread over the field as mulch (RM). Results showed that N2O emission was decreased by 24–29% in Treatment RB and by 3–18% in Treatment RI, but increased by 15–39% in Treatment RM,
compared with that in Treatment CK. The contents of soil total C and N at wheat harvest were significantly increased by 7–13%
and by 8–12% in Treatment RI, respectively, compared with that in Treatment CK. The wheat grain yield in Treatment RI was
1.0–1.2 times that in the Treatment CK. Based on these results, the best management practice of returning rice straw to the
soil prior to wheat cultivation is evenly incorporating rice straw into the topsoil, as the method tended to reduce N2O emission during the wheat-growing season and increase wheat yield and soil fertility. 相似文献
57.
Jane M. Sayer Jamshed H. Shah Chengyi Liang Guojian Xie Heiko Kroth Haruhiko Yagi 《Polycyclic Aromatic Compounds》2013,33(1-4):95-104
For oligonucleotide duplexes derived from trans opening of benzo[a]pyrene diol epoxides (BaP DEs) by the exocyclic N6-amino group of deoxyadenosine (dA), the hydrocarbon is intercalated toward the 5′-end of the modified strand when the configuration at the site of attachment of the base to the hydrocarbon (C-10) is R, and toward the 3′-end when this configuration is S. In oligonucleotide 11-mer duplexes modified by BaP DE-1 (benzylic 7-OH and epoxide oxygen cis) and DE-2 (7-OH and epoxide oxygen trans), as well as 7,8,9,10-tetrahydro BaP 9,10-epoxide, 10R adducts had consistently higher (5–9d°C) Tm values than the corresponding 10S adducts. Dodecamer duplexes from the HPRT gene with trans opened 10S (but not those with 10R) BaP DE-2 adducts at either of two adjacent dA residues exhibited blue shifts at ~350 nm at temperatures well below the Tm. We propose that these blue shifts result from a conformation in which the hydrocarbon is not stacked with the DNA bases. 相似文献
58.
Atsushi Tsutsumi Hidehiko Suzuki Yasushi Saito Kunio Yoshida Ryohei Yamazaki 《Powder Technology》1998,100(2-3):237-241
The granulation of multi-component particles was conducted in a fast fluidized bed with an atomizing binder solution. The effects of gas velocity and binder droplet diameter on granulation rate, granule size distribution and granule composition were studied. The granulation rate and granule yield were determined by the balance between the agglomeration rate of feed particles and the disintegration rate of granules because there was no secondary granulation. With the increase in gas velocity and the reduction in binder droplet size, the agglomeration rate of feed particles decreased but the disintegration rate of granules increased, resulting in a reduced granule yield. Despite the larger fraction of small particles in the granules, the homogenous granulation of multi-component particles was achieved. 相似文献
59.
Smooth CuLa0.98Eu0.02O2 thin film has successfully been prepared by pulsed laser deposition method at room temperature. Crystal structure of the obtained film was almost same as that of CuLa0.98Eu0.02O2 polycrystalline ceramic. Orange luminescence with high intensity due to 5D0 – 7F0,1 transitions of Eu3+, which was an evidence of Eu3+ substitution for La3+ site in LaO6 octahedra with the inversion symmetry, was also observed in the obtained film. The optical band gap of CuLa0.98Eu0.02O2 was measured to be 2.85 eV from absorption spectroscopy. 相似文献
60.
The Fushime geothermal field is located in a depression close to the coast line. The system is characterized by very high reservoir temperature (>350°C), and a high salinity production fluid. Geological analysis shows that the main reservoir in this field occurs in a fractured zone developed around a dacite intrusion located in the center of the field. High permeability zones recognized by drilling data are found to be associated with fault zones. One of these zones is clearly associated with a NW–SE trending andesite dike swarm which was encountered in some wells.Alteration in the system can be divided into four zones, in order of increasing temperature, based on calcium–magnesium aluminosilicate mineral assemblages: i.e., the smectite, transition, chlorite and epidote zones. The feed zone is located in the chlorite and epidote zones, which can be further divided into three sub-zones according to their potassium or sodium aluminosilicate mineralogy, from the center of the discharge zone: K-feldspar–quartz, sericite–quartz, and albite–chlorite zones.Chloride concentration of the sea-water is 19,800 mg/l, and Br/Cl mole ratio is 1.55. Based on geochemical information, the reservoir chloride concentration of this field ranges from 11,600 to 22,000 mg/kg. The Clres (Cl in reservoir), Br/Cl ratios and stable isotope data indicate that the Fushime geothermal fluid originated from sea-water and is diluted by ground water during its ascent. Some fluids produced from geothermal wells show low pH (about 4). It is thought that sulfide mineral (PbS, ZnS) precipitation during production produces this acidic fluid. 相似文献