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排序方式: 共有315条查询结果,搜索用时 15 毫秒
1.
Minoru Tsuda Setsuko Oikawa Akira Yokota Mitsuo Yabuta Wataru Kanai Ken-Ichi Kashiwagi Isamu Hijikata Hisashi Nakane 《Polymer Engineering and Science》1983,23(18):993-999
A dry developable negative working resist composition comprised of poly(methyl isopropenyl ketone) (PMIPK) and 4-methyl-2,6-di(4′-azido-benzylidene) cyclohexanone-1 was examined. The main photochemical product formed in the resist pattern was found to be a secondary amine which crosslinks PMIPK. Post-annealing forms a hydrogen-bonded product which shows a powerful electronic excitation energy quenching effect. The quencher is more powerful than the aromatic compound arising from the azide by post-annealing only. The residual resist thickness of the negative pattern is about 80 percent of the initial thickness of the coating in spite of all the azide compound remaining in the resist coating. The obtained dry developed resist pattern has a high dry etch resistance. Etchings of Si and SiO2 were performed by plasma and reactive ion etching, respectively. 相似文献
2.
Three samples of LaCoO3 were prepared by two different methods and calcined at 800 or 1000 °C. They had BET areas of 1, 12, and 16 m2/g and all of them showed pure perovskite X-ray diffraction patterns with identical unit cell dimensions. In a series of experiments the oxide, having larger surface area, was stepwise reduced in hydrogen at temperatures between 60 and 500 °C. The XPS spectra, taken at room temperature after evacuation at 400 °C at each reduction level, showed that the surface concentration of Co° was very low up to 300 °C but increased sharply between 300 and 350 °C (9–75%). This concentration further increased to 100% after 10 min reduction at 450 °C, but upon heating in hydrogen for an additional 10 min at 500 °C it decreased again to 75%. In another series of experiments the mixed oxide was reoxidized after each reduction. A fresh sample was reduced to 350 and 400 °C by contacting with hydrogen for 1 hr and evacuated at temperatures between 400 and 500 °C. Both high evacuation temperatures and reduction at 400 °C during 1 hr produced a sharp decrease in Co° surface concentration. These results are consistent with the catalytic behavior of this perovskite reported earlier by E. A. Lombardo et al. (4–7). A model is proposed to interpret the reduction of LaCoO3. 相似文献
3.
Isamu Yamauchi Takashi Okamoto Hajime Ohata Itsuo Ohnaka 《Journal of Alloys and Compounds》1997,260(1-2):162-171
The effects of Cu addition on the β phase formation rate and the thermoelectric power in various FeSi2 and Fe2Si5 based alloys was examined. The peritectoid reaction (a+→β) in FeSi2 alloys was initially enhanced by the addition of Cu but it became slower for longer annealing times. The retained metallic ε was harmful for the thermoelectric power. The inherent thermoelectric properties of (FeSi2)99−XMn1CuX (X=0–1.O at.%), (FeSi2)99−X Co1CuX (X=0–1.0 at.%) alloys were attained after the elimination of ε. In the case of eutectoid reaction (→β+Si). Differential thermal analysis, X-ray diffraction and microscopic observation clearly confirmed that the eutectoid reaction rate was drastically enhanced by the addition of a small amount of Cu and its rate decreased with decreasing Cu content. The rate also depends on the annealing temperature and reached a maximum at about 1073 K for most alloys. The addition of only 0.1 at.% Cu was still very effective even in Mn or Co doped alloys. The thermoelectric power of these alloys increased very quickly with annealing time. Their final values decreased with Cu content and saturated at 0.2 at.% Cu. The value of the 0.1 at.% Cu added alloy was higher than that of both the conventional p- and a-type FeSi2 based alloys. These results suggest that the Fe2Si5 alloys with a small amount of Cu may be attractive as new thermoelectric materials. 相似文献
4.
Crystallite size distribution and the lattice distortions in highly γ-irradiated linear polyethylene
Crystallite size distributions and lattice distortions have been analysed for highly-irradiated linear polyethylene in the direction normal to 1 1 0 and 0 0 1 lattice planes through X-ray line profile analysis. It has been found that the lateral crystallite size is little affected irradiation greater than 1000 Mrad, whereas that in the chain direction decreases almost linearly with the dose of irradiation. A minor difference in the crystallite size between irradiation atmospheres, i.e. irradiation in air or in vacuum, has been disclosed at a very high dose of irradiation. The above degradation behaviour of crystallites and the change in lattice distortions have proved that radiation cross-links are mainly formed in the amorphous region near the lamellar surface of polyethylene. 相似文献
5.
Isamu Ogura Mari Kotake Hiromu Sakurai Kazumasa Honda 《Aerosol science and technology》2016,50(8):846-856
The flat surface of Nuclepore filters is suitable for observing collected particles with a scanning electron microscope (SEM). However, experimental data on surface-collection efficiency are limited because surface-collection efficiencies cannot be measured directly using aerosol measuring instruments. In this study, the surface-collection efficiencies of Nuclepore filters were determined by establishing the ratio of the number of particles deposited on the surface of the filter visually counted with an SEM to the number of inflow particles counted by a condensation particle counter, using monodispersed polystyrene latex particles (30–800 nm) and silver particles (15–30 nm). Because Nuclepore filters with smaller pore sizes would be expected to produce higher minimum surface-collection efficiency and a higher pressure-drop, 0.08 and 0.2 µm Nuclepore filters were chosen as the test filters in view of both collection efficiency and pressure drop. The results showed that the minimum surface-collection efficiencies of the 0.08 µm pores at face velocities of 1.9 and 8.4 cm·s?1 were approximately 0.6 and 0.7, respectively, and those of the 0.2 µm pores at face velocities of 1.5 and 8.6 cm·s?1 were approximately 0.8 and 0.6, respectively. Because the pressure drop of the 0.2 µm pore filter was lower than that of the 0.08 µm pore filter under the same flow-rate conditions, the 0.2 µm pore filter would be more suitable considering the pressure drop and collection efficiency. The obtained surface collection efficiencies were quantitatively inconsistent with theoretical surface-collection efficiencies calculated using conventional theoretical models developed to determine the collection efficiency of filters with larger pores.© 2016 American Association for Aerosol Research 相似文献
6.
Isamu Ogura Naomi Hashimoto Mari Kotake Hiromu Sakurai Atsuo Kishimoto Kazumasa Honda 《Aerosol science and technology》2014,48(7):758-767
A simple sampling method to collect aerosol particles for transmission electron microscope (TEM) analysis was developed by R’mili and others in 2013. The method involves passing air through a holey carbon film-coated copper mesh TEM grid (holey carbon grid) and sampling particles by filtration. In this study, we proposed a modified calculation method to represent the collection efficiencies of holey carbon grids, taking into consideration the porosity of the copper mesh. We then evaluated the particle collection efficiencies of holey carbon grids both theoretically and experimentally. We tested the collection efficiency of two types of holey carbon grids, with nominal pore sizes of 1.2 and 0.6 μm, using particles of monodispersed polystyrene latex (PSL) and potassium chloride. The overall collection efficiency of each grid (Egrid) was determined by the downstream/upstream concentration ratio measured by condensation particle counters (CPCs). In addition, for PSL particles, the collection efficiency of the holey carbon film (Efilm) was determined by the ratio of the number of particles on the film (counted on a scanning electron microscope) to the number of inflow particles (counted by a CPC). We compared model calculations against the experimental results obtained in this study and those reported by R’mili and others in 2013. These data showed that the calculated Egrid values were in reasonably good agreement with the experimental Egrid values. However, although the model calculation indicated that Efilm ≈ Egrid, there was an inconsistency between the experimental Efilm and Egrid, which requires further investigation in order to determine its cause.
Copyright 2014 American Association for Aerosol Research 相似文献
7.
Xiong Wei Wu Tomoo Yamamura Suguru Ohta Qi Xiu Zhang Fu Cong Lv Can Ming Liu Kenji Shirasaki Isamu Satoh Tatsuo Shikama Dan Lu Su Qin Liu 《Journal of Applied Electrochemistry》2011,41(10):1183-1190
The redox kinetics of VO2+/VO2 + and V3+/V2+ couples on a carbon paper (CP, HCP030 N, Shanghai Hesen, Ltd., China) electrode were investigated in terms of their standard rate constant (k 0) and reaction mechanism. The values determined for k 0 for VO2+ ?? VO2 + and V3+ ?? V2+ using the CP electrode are 1.0 × 10?3 and 1.1 × 10?3 cm s?1, respectively. The value of k 0 increases by one or two order(s) of magnitude compared with values obtained using electrodes composed of pyrolytic graphite and glassy carbon. The acceleration of the redox kinetics of vanadium ions is a result of the large surface area of the CP electrode. An inner-sphere mechanism for the reaction on the surface of the electrode is proposed. The kinetic features of vanadium redox reactions on the CP electrode reveal that CP is suitable for use as the electrodes in vanadium redox-flow batteries. 相似文献
8.
Naoya Miyahara Shuhei Miwa Naoki Horiguchi Isamu Sato Osaka Masahiko 《Journal of Nuclear Science and Technology》2019,56(2):228-240
In order to improve LWR source term under severe accident conditions, the first version of a fission product chemistry database named ‘ECUME’ was developed. The ECUME is intended to include several datasets of major chemical reactions and their effective kinetic constants for representative severe accident sequences. It is expected that the ECUME can serve as a fundamental basis from which fission product chemical models can be elaborated for use in the severe accident analysis codes. The implemented chemical reactions in the first version were those for representative gas species in Cs-I-B-Mo-O-H system from 300 to 3000 K. The chemical reaction kinetic constants were evaluated from either literature data or calculated values using ab-initio calculations. The sample chemical reaction calculation using the presently constructed dataset showed meaningful kinetics effects at 1000 K. Comparison of the chemical equilibrium compositions by using the dataset with those by chemical equilibrium calculations has shown rather good consistency for the representative Cs-I-B-Mo-O-H species. From these results, it was concluded that the present dataset should be useful to evaluate fission product chemistry in Cs-I-B-Mo-O-H system under LWR severe accident conditions, where kinetics effects should be considered. 相似文献
9.
Isamu Yoshitake Narifumi Yasumura Masayuki Syobuzako Andrew Scanlon 《Canadian Metallurgical Quarterly》2011,25(2):71-86
In order to prevent traffic accidents on snow-covered bridge decks, the writers developed a new pipe heating system that uses only groundwater stored in a large underground tank. The underground tank provides geothermal energy, i.e., groundwater of constant temperature, through heating pipes embedded in concrete pavements with no electric heater or fuel boiler. The pipe heating system was constructed at approximately 50% of the cost of comparable systems. In addition, there is a reduction of 10% in operating costs compared with the previous system. The present paper outlines its design and construction and provides fundamental data for the developed system. The piped heating system has kept the road conditions safe during the winter season by always removing the snow and ice from the heated road and bridge sections earlier than the surrounding roads. According to long-term temperature measurements, this system has prevented the road temperature from decreasing below 0°C, even through nighttime and morning periods. This report presents the system as an economical and effective solution for snow thawing and ice prevention. 相似文献
10.
In a proposed switching grating coupler (SGC), the grating period Lambda is chosen so that the SGC converts from a first-order grating coupler to a third-order distributed Bragg reflector by means of a small change in the guided mode index. The principle for switching the radiated wave power and the effective aperture of the SGC were experimentally confirmed by use of the thermo-optic effect of a polymer waveguide. The extinction of the peak intensity of the wave radiated by the SGC and collected by an external lens was measured to be 5 dB with a temperature change of 10 degrees. 相似文献