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51.
Chlorine auto-doping phenomenon was found for the first time in InP epitaxial growth by using a PCl3/InP/H2 system. Chlorine atoms act as a donor in the epitaxial layer and the carrier concentration is dependent on the facet of InP
substrate. The carrier concentration of the InP layer on ( 111)B facet was over 103 times higher than that on (111)A substrate. 相似文献
52.
Manabu Iguchi Yukio Terauchi Shin-Ichiro Yokoya 《Metallurgical and Materials Transactions B》1998,29(6):1219-1225
Bubble formation from a single-hole nozzle placed vertically upward in a rotating water bath was investigated using a high-speed
video camera. Air was used as the working gas. The measured values of the frequency of bubble formation, f
B, were compared with those observed in a stationary bath, f
B0. The velocity of cross-flow, νθ, affected the bubble formation significantly when it exceeded a critical value, νθc
. The ratio of f
B to f
B0 was unity for νθ≦νθc
, but it changed in a complex manner for νθ>νθc
. In the latter case, when the air flow rate Q
g was relatively low, f
B/f
B0 became larger than unity irrespective of Q
g, and an empirical correlation of f
B/f
B0 was proposed as a function of νθ and the inner diameter of the nozzle, d
ni. As the gas flow rate increased, f
B/f
B0 decreased monotonically and became smaller than unity, and an empirical correlation of f
B/f
B0 was derived as a function of Q
g, νθ, and d
ni. These empirical correlations could approximate the measured values of f
B/f
B0 within a scatter of −15 to +20 pct. 相似文献
53.
Tetrahydropyranyl- (THP) and furanyl- (THF) protected polyhydroxystyrene (PHS) polymers have been investigated for their potential use in conjunction with onium salt acid precursors to yield high-sensitivity resist systems. The synthesized polymers have high transmittance at 248 nm (the wavelength used in next-generation excimer laser, KrF exposure tools). At 248 nm the transmittance for a 1-μm thick film is ~ 80% (Abs = 0.097 μm?1). The acid sensitivity of the acetal functionality at room temperature is high, requiring careful handling of all materials to prevent any premature deprotection of the hydroxy group. The highest lithographic sensitivities obtained so far with a system consisting of poly(p-tetrahydropyranyl-oxy-styrene) base resin and 1 mol % of bis (p-tert-butyl phenyl) iodinium triflate (TBIT) was ~ 2 mJ / cm2. High-resolution line and space patterns (0.35 μm) were obtained with a system comprising PHS-p-THP and an acid precursor, using an excimer laser step and repeat exposure at 248 nm. 相似文献
54.
Nobuaki Kamimoto Yutaka Yamada Masami Kitamura Kiyoshi Nishikawa 《Artificial Life and Robotics》2005,9(1):7-11
We propose a method of evaluating the vibration of motor-operated electric tools (MOETs) by using a self-organizing feature map (SOM). The vibration spectrum is used to evaluate the MOET vibration. These vibration spectra are derived from 18 vibration data obtained by measurements on three different positions of a MOET. The spectra are then sent to the SOM network for the calculations. The vibration spectra are classified by the SOM, and calculations give the Euclidean distance from the weight vector in order to develop a quantitative evaluation. A statistic analysis of the Euclidean distance allows a quantitative evaluation of a MOET with respect to vibration stress and other relevant parameters.This work was presented, in part, at the 9th International Symposium on Artificial Life and Robotics, Oita, Japan, January 28–30, 2004 相似文献
55.
In 1977, Tagashira and colleagues reported that the center‐of‐mass drift velocity Wr of an electron swarm defined in time of flight (TOF) takes a larger value than the drift velocity Wv defined in pulsed Townsend (PT) when ionization collisions take place. At the same time, they explained that the larger values of Wr are caused by the ionization generation of electrons at the front side of extending swarm due to higher mean energy. In this paper, a new definition of virtual drift velocity in configuration space W′r defined in PT is proposed, and calculated data of drift velocities and related quantities such as ionization coefficients and ionization frequencies in Ar in a high E/N range are discussed relative to Tagashira's data. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 155(2): 1–7, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20131 相似文献
56.
Rough ideals in semigroups 总被引:42,自引:0,他引:42
Nobuaki Kuroki 《Information Sciences》1997,100(1-4):139-163
We shall introduce the notion of a rough left [right, two-sided, bi-] ideal in a semigroup, which is an extended notion of a left [right, two-sided, bi-] ideal in a semigroup, and give some properties of such ideals. 相似文献
57.
58.
K Ozawa H Miura T Tamagawa Y Hiyoshi K Nonogaki N Maeda G Watanabe N Sakamoto A Iguchi 《Canadian Metallurgical Quarterly》1993,53(25):1903-1909
We investigated the effects of intrahypothalamic or hippocampal injection of GABA receptor agonists on hyperglycemia induced by hippocampal neostigmine. Prior to the injection of neostigmine (50 nmol) into the hippocampus (HPC), muscimol (0.01-1 nmol) or baclofen (1 nmol) was injected into the bilateral ventromedial hypothalamus (VMH). Muscimol suppressed the hyperglycemia in a dose-dependent manner, but baclofen affected it only minimally. In contrast, neither hippocampal muscimol (1 or 2.5 nmol) nor baclofen (1 nmol) suppressed the hippocampal neostigmine-dependent hyperglycemia. Intrahypothalamic muscimol (1 nmol) also decreased the changes in hepatic venous plasma glucagon and epinephrine significantly. These results indicate that intrahypothalamic muscimol suppresses hyperglycemia caused by cholinergic neurons originating from the HPC, indicating existence of the location specificity. 相似文献
59.
60.
In addition to the dielectric relaxation around 170 K in the cubic structure of Sr1–3x/2La
x
TiO3, a similar relaxation was observed at about 70 K in the tetragonal structure with an activation energy in the range 0.13–0.16 eV which increases as x in Sr1–3x/2La
x
TiO3 varies from 0.60–3.00 at%. This relaxation is explained by Skanavi's model and is discussed in terms of thermal motions of Ti4+ between potential minima produced by lattice distortions in the tetragonal structure. In order to provide a direct evidence for the suggestion that the dielectric relaxation around 170 K in the cubic is due to thermal motions of Ti4+, dielectric properties on manganese-doped specimens, Sr1–3x/2La
x
Mn
y
Ti1–y
),O3 with x=1.40×10–2 and y=0.1×10–2, were investigated because Mn4+ substitutes for Ti4+. As well as the relaxation due to Ti4+, this specimen exhibits another peak due to Mn4+ with an activation energy somewhat smaller than that of Ti4+. The activation energies and the relative intensity of these relaxation processes are explained by the difference in ionic radii of Mn4+ and Ti4+ and the difference in formation energies of a strontium vacancy adjacent to Mn4+ and that to Ti4+, which were calculated theoretically using a shell model. 相似文献