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141.
Shiraishi K. Kawasaki N. Yoda H. Watanabe K. Umetsu M. Hitomi T. Muro K. 《Lightwave Technology, Journal of》2009,27(7):864-870
A new scheme for lensed fibers with a high focusing power is proposed. The new lensed fiber has a high-index layer coated (HILC) on a convex-shaped endface of a single-mode fiber (SMF). Numerical investigation shows that, by coating a 10-mum-thick film with refractive index of 3.7, the lensed fiber can contract the beam diameter of the propagating mode from 10.4 mum at the wavelength of 1.55 mum, to 1.2 mum. The enhanced focusing effect of the lensed fiber has been confirmed experimentally by coating an a-Si:H film on the lensed endface. The measured focused spot diameter was as small as 1.6 mum, much the same as the wavelength. 相似文献
142.
A new technique is proposed for integration of bulky optical components by means of a specific graded-index fiber in which the fundamental mode has a large mode-field diameter (MFD). A wide-beam propagating (WBP) fiber with the field diameter as large as 60 /spl mu/m was successfully fabricated, which will enable bulky optical components that have no wave-guiding structures to be embedded into a fiber circuit without any lenses. It was confirmed that a 5-mm-thick silicon plate, for example, can be integrated into the fiber with a loss of less than 1 dB. A hemispherically ended WPB fiber for much longer bulky components is also proposed. 相似文献
143.
Four thermophysical properties of both solid and liquid molybdenum, namely, the density, the thermal expansion coefficient, the constant-pressure heat capacity, and the hemispherical total emissivity, are reported. These thermophysical properties were measured over a wide temperature range, including the undercooled state, using an electrostatic levitation furnace developed by the National Space Development Agency of Japan. Over the 2500 to 3000 K temperature span, the density of the liquid can be expressed as
L(T)=9.10×103–0.60(T–T
m) (kg·m–3), with T
m=2896 K, yielding a volume expansion coefficient
L(T)=6.6×10–5 (K–1). Similarly, over the 2170 to 2890 K temperature range, the density of the solid can be expressed as
S(T)=9.49×103–0.50(T–T
m), giving a volume expansion coefficient
S(T)=5.3×10–5. The constant pressure heat capacity of the liquid phase could be estimated as C
PL(T)=34.2+1.13×10–3(T–T
m) (J·mol–1·K–1) if the hemispherical total emissivity of the liquid phase remained constant at 0.21 over the temperature interval. Over the 2050 to 2890 K temperature span, the hemispherical total emissivity of the solid phase could be expressed as
TS(T)=0.29+9.86×10–5(T–T
m). The latent heat of fusion has also been measured as 33.6 kJ·mol–1. 相似文献
144.
A Hashi T Yasumizu I Yoda T Kou K Mizuno S Hirata J Kato R Katoh M Inoue A Kawaguchi M Nakazato T Onaya 《Canadian Metallurgical Quarterly》1996,61(3):427-431
GABAA agonists do not respond to the same degree to allosteric modulators of the GABAA receptor complex such as benzodiazepines. We report there the effects of two steroids (alfaxalone and pregnenolone sulfate) on the inhibition induced by two GABAA agonists, 3-amino propane sulphonic acid (3-APS) and muscimol, on the extracellular evoked potentials obtained in CA1 of mice hippocampi. Alfaxalone (1 microM) potentiates the effects of both agonists, although incubation times longer than 15 minutes are required to potentiate the inhibitory effect of muscimol. Lower doses of pregnenolone sulfate at shorter incubation periods are able to inhibit the effects produced by single doses of 3-APS as compared to muscimol (15 microM during 5 min vs 30 microM during 5 min). Our results confirm the possibility that there might be differences in the interaction between GABAA agonists and modulatory steroids. 相似文献
145.
P.?-F.?ParadisEmail author T.?Ishikawa Y.?Saita S.?Yoda 《International Journal of Thermophysics》2004,25(6):1905-1912
Some thermophysical properties of liquid and supercooled palladium were measured using containerless techniques. Over the 1640–1875 K temperature interval, the density could be expressed as (T)=10.66× 103 –0.77(T–Tm)(kg·m–3) and the ratio between the isobaric heat capacity and the hemispherical total emissivity could be rendered as (J·mol–1·K–1), where Tm=1828 K. The volume expansion coefficient was also determined as 7.2 × 10–5 K–1. 相似文献
146.
Summary
This article deals with the living radical emulsion
photopolymerization of methyl methacrylate (MMA) using a RAFT
agent which plays the role of an initiator in the absence of an
additional thermal initiator, a chain-transfer agent, and a
surfactant. The mechanism of the formation of stable spherical
polymer beads without coagulation in the absence of a surfactant
and the effects of the added surfactant are studied. The
molecular weights of the prepared PMMA beads are in the same
range (Mn: 105
- 106 g/mol) as those obtained from a
conventional emulsion polymerization. However, the molecular
weight distribution
(Mw/Mn;
polydispersity index; PDI) is controlled to be less than 2.0.
The polymer beads in diameter was significantly reduced from 300
nm without a surfactant to decreased to 50 nm upon the addition
of sodium dodecyl sulfate (SDS) keeping the molecular weight and
the molecular weight distribution constant. Also, the addition
of SDS in the preparation of PMMA colloid results in the
enhancement of the stability by exhibiting increased -potential
values in water 相似文献
147.
Several thermophysical properties of hafnium-3 mass % zirconium, namely the density, the thermal expansion coefficient, the constant pressure heat capacity, the hemispherical total emissivity, the surface tension and the viscosity are reported. These properties were measured over wide temperature ranges, including overheated and undercooled states, using an electrostatic levitation furnace developed by the National Space Development Agency of Japan. Over the 2220 to 2875 K temperature span, the density of the liquid can be expressed as
L
(T)=1.20×104–0.44(T–T
m
) (kgm–3) with T
m
=2504 K, yielding a volume expansion coefficient
L
(T)=3.7×10–5 (K–1). Similarly, over the 1950 to 2500 K span, the density of the high temperature and undercooled solid -phase can be fitted as
S
(T)=1.22×104–0.41(T–T
m
), giving a volume expansion coefficient
S
(T)=3.4×10–5. The constant pressure heat capacity of the liquid phase can be estimated as C
PL
(T)=33.47+7.92×10–4(T–T
m
) (Jmol–1K–1) if the hemispherical total emissivity of the liquid phase remains constant at 0.25 over the 2250 K to 2650 K temperature interval. Over the 1850 to 2500 K temperature span, the hemispherical total emissivity of the solid -phase can be represented as
TS
(T)=0.32+4.79×10–5(T–T
m
). The latent heat of fusion has also been measured as 15.1 kJmol–1. In addition, the surface tension can be expressed as (T)=1.614×103–0.100(T–T
m
) (mNm–1) and the viscosity as h(T)=0.495 exp [48.65×103/(RT)] (mPas) over the 2220 to 2675 K temperature range. 相似文献
148.
Yoda H. Ohuchi Y. Taniguchi Y. Ejiri M. 《IEEE transactions on pattern analysis and machine intelligence》1988,10(1):4-16
An automatic wafer pattern inspection system has been developed that can detect defective patterns 6 μm or larger in multilayered wafer patterns at a speed 30 times faster than that of a human inspector. The false-alarm rate is less than 0.5 occurrences/chip. This performance is achieved mainly by the use of a special comparison method between two adjacent patterns obtained through a single optical setup, and also by the use of digital design pattern data (CAD data). The main functions of the design pattern data are to specify the inspection area, to designate optimum parameters for inspection, and to separate defective portions into different layers, thereby facilitating the classification of the defects. All image processing is performed in one pass by a high-speed pipeline-structured image processor that can analyze an input image signal at a 7 MHz video rate 相似文献
149.
Long term competition between sulfate-reducing and methane-producing bacteria for acetate in anaerobic biofilm 总被引:3,自引:0,他引:3
A long term competition between sulfate-reducing bacteria (SRB) and methane-producing bacteria (MPB) for acetate was investigated using a laboratory scale anaerobic fluidized bed. When the synthetic wastewater composed of acetate and sulfate was fed at a low organic loading rate, averages of the remaining acetate and sulfate concentrations were 1.7 mg Cl−1 and 78.5 mg l−1, respectively. During several months of this acetate limited operation the methane production rate as well as the microbial mass of MPB declined gradually, whereas the amount of reduced sulfate along with the microbial mass of SRB increased, which apparently indicates that SRB out-compete MPB in the biofilm at lower acetate concentrations. On the other hand, MPB were able to form a biofilm faster than SRB at higher acetate concentrations presumably due to MPB's higher ability to adhere carrier surfaces compared with SRB. Kinetic constants for both species in the biofilm were determined and compared with those reported for pure MPB and SRB cultures. Based on the kinetic mechanism of this competition, operational conditions which would support methanogenesis by suppressing sulfate reduction were identified. 相似文献
150.