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91.
It is demonstrated that resonance surface X-ray scattering (RSXS), in which incident X-ray energy close to the Pt LIII absorption edge (11.55 keV) is used, is very useful for the determination of the structure of electrodeposited Pt thin layers on a Au(1 1 1) surface. This technique was applied to characterize the structure of electrodeposited Pt layers on Au(1 1 1) substrates prepared under two extreme conditions, which are known to provide rough and atomically flat layers. Detailed structural information was obtained by RSXS measurements and it was confirmed that the structures of the Pt layers were as reported. Pt atoms of the atomically flat monolayer were found to be situated at the threefold hollow cubic closest packing (ccp) sites of the Au(1 1 1)-(1 × 1) surface.  相似文献   
92.
Deposition rate of droplets in steam-water annular two-phase flow was measured using a 5 mm diameter vertical round tube as a test section. In the experimental conditions tested in this work, the droplet mass transfer coefficient decreased with an increase in the droplet concentration in the gas core flow and with an increase in the length of a deposition section. The dependence on these two parameters agreed fairly well with predictions by available correlations. Placing a small cylindrical tube concentrically in the test section round tube, the effect of a flow obstacle on the deposition rate of droplets was also experimentally investigated. It was found that the obstacle effect was significant and the deposition rate of droplets increased approximately three times in average. The obstacle effect measured in this work was compared with an empirical correlation and a simple mechanistic model that were developed using experimental results of air-water annular flows. Fairly good agreement was achieved in both cases, which would indicate that the mechanism of deposition enhancement induced by the flow obstacle is similar between air-water and steam-water flows.  相似文献   
93.
94.
The authors have proposed a new concept of a distribution system “Flexible, Reliable and Intelligent ENergy Delivery System (FRIENDS)” with intent to solve imminent operating problems faced by utilities in providing their customers with reliable supply of power at several levels of quality. The main idea of FRIENDS is to introduce new facilities, so‐called Quality Control Centers (QCCs), which are installed very close to the customers for the purpose of implementing multiple functions, such as Customized Power Quality Service. In addition, these QCCs form a network for energy and information transmission at a level below distribution substations. QCCs make it possible to frequently change configuration of the network depending on the system and load conditions. These frequent reconfigurations of the network require fast and reliable Transfer Switching in the QCCs to ease an effect on customers. The reconfiguration for the purpose of fault area isolation also requires a fast Fault Detection feature. This paper presents a new method for controlling Transfer Switching and a method of Fault Detection in order to realize a fast and reliable reconfiguration of QCC network in a normal state, as well as under fault conditions. This paper also analyzes the methods in terms of instantaneous values calculated by PSCAD/EMTDC. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(3): 25–35, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10298  相似文献   
95.
We developed a new in-situ process for preparing functional ceramic fibers with a gradient surface layer by means of precursor methods using a polycarbosilane. After incorporation of selected low-molecular-mass additives into the precursor polymer from which the ceramic forms, thermal treatment of the resulting bodies leads to controlled phase separation ("bleed out") of the additives. Subsequent calcination stabilizes the compositionally changed surface region, generating a functional surface layer. Using this technology, we developed a strong photocatalytic fiber (TiO2-covered SiO2 fiber), which effectively decomposed many types of organic chemicals and bacteria into CO2and water by irradiation with UV light. Furthermore, we performed some field tests using a circulation purifier with a module composed of the cone-shaped felt material of our new fiber.  相似文献   
96.
One of the important factors for designing solar house is to examine the most economic combination what is called optimum design between solar collector area and storage volume for the required energy demand. The result of experimentation gives the fundamental data for completing the computer simulation program that is effectively usable for designing solar house.  相似文献   
97.
Plasma polymers from some silyl amines were produced by the radio frequency of 13.56 MHz, and the surface properties were investigated. The polymers were revealed to be as hydrophobic as a plasma polymer from tetramethylsilane, which does not contain nitrogen. The hydrophobicity became effective at around 50 Å thicknesses of these polymer layers deposited on micro-slide glass. These polymers have gradually become comparatively hydrophilic with the aging. The change of wettability is probably due to the oxidation of these surface layers to form oxides and peroxides, which are more hydrophilic. The hydrophobic character of silyl amine plasma polymers could be explained by the lack of amines and/or amides in these polymers, as observed with ATR-IR and ESCA spectra. These spectroscopic observations also suggest that nitrogen is a more fragile element in plasma than carbon or silicon in the silyl amines.  相似文献   
98.
The unsaponifiables from 19 vegetable oils were divided into 4-methylsterol fraction, triterpene alcohol fraction and two other fractions by thin layer chromatography. The 4-methylsterol and triterpene alcohol fractions were analyzed by gas liquid chromatography, and identification of major components was carried out by gas liquid chromatography and combined gas chromatography-mass spectrometry. Gramisterol(24-methylenelophenol), citrostadienol and obtusifoliol were present in all oils, and the presence of a 4-methylsterol, presumably cycloeucalenol, was indicated in most of the oils. Cycloartenol and 24-methylenecycloartanol were found as common triterpene alcohols in all oils, and the occurrence of cyclobranol(24-methylcycloartenol), cycloartanol, and α- and β-amyrins was demonstrated in most of the oils.  相似文献   
99.
Woodceramics are new porous carbon materials obtained by carbonizing wood or woody material impregnated with thermosetting resin such as phenol resin in a vacuum furnace. During the carbonizing process, thermosetting resin changes into glassy carbon, which has superior corrosion resistance and mechanical strength, reinforces the material and suppresses the fissures and warps (caused by the porous structure specific to wood) that develop during thermoforming. The dimension, weight decrease rate, and electrical characteristics depend on the thermoforming temperature. The manufacturing method of Woodceramics is introduced in this paper and various industrial uses, such as electromagnetic shields, are discussed.  相似文献   
100.
A single-phase diode bridge rectifier with a filter capacitor on the dc side is often employed to convert ac input into a dc voltage. The input current of the rectifier contains harmonic currents which cause undesirable power line effects. Recently, a method using the time domain analysis has been proposed to calculate the harmonic currents of rectifier considering noninfinite capacitance, i.e., non-zero dc side impedance. This method is very accurate, but it requires a long computing time and a complicated algorithm. This paper proposes a new method that makes it possible to easily calculate the harmonic currents taking into account the effects of the ac and dc side impedances of rectifier. The proposed method, which is based on the frequency domain method, can be executed only with the algebraic computation, and its accuracy is quite high. The validity of the proposed method is also demonstrated by comparison with the results of time simulation.  相似文献   
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