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排序方式: 共有412条查询结果,搜索用时 15 毫秒
101.
Yasushi Ozawa Yoshihisa Tochihara Noriyuki Mori Isao Yuri Junichi Sato Koji Kagawa 《Catalysis Today》2003,83(1-4):247-255
A catalytically assisted ceramic combustor for a gas turbine was designed and tested to achieve low NOx emissions. This combustor is composed of a burner and a ceramic liner. The burner consists of an annular preburner, six catalytic combustor segments and six premixing nozzles, which are arranged in parallel and alternately. In this combustor system, catalytic combustion temperature is controlled under 1000 °C, premixed gas is injected from the premixing nozzles to the catalytic combustion gas and lean premixed combustion over 1300 °C is carried out in the ceramic liner. This system was designed to avoid catalyst deactivation at high temperature and thermal shock fracture of the ceramic honeycomb monolith of the catalyst. A 1 MW class combustor was tested using LNG fuel. Firstly, NOx emissions from the preburner were investigated under various pressure conditions. Secondly, two sets of honeycomb cell density catalysts and one set of thermally pretreated catalysts ware applied to the combustor, and combustion tests were carried out under various pressure conditions. As a result, it was found that the main source of NOx was the preburner, and total NOx emissions from the combustor were approximately 4 ppm (at 16% O2) at an adiabatic combustion temperature of 1350 °C and combustor inlet pressure of 1.33 MPa. 相似文献
102.
Seiichi Deguchi Hitoki Matsuda Masanobu Hasatani Noriyuki Kobayashi 《Drying Technology》1994,12(3):577-591
Fine particles of Tio2 were prepared from titanyl sulfate solution by the Spray pyrolysis Method( SPM) The reaction tube was divided into four zones: drying, dehydration, pyrolysis 1 and pyrolysis 2 zones. Under various reaction temperature and carrier gas flow rate, the mean size and the size distribution of particles collected at different sampling positions along the axial direction of the reactor were compared. The effects of operating conditions of drying, dehydration and subsequent pyrolysis steps on the formation mechanism of Tio2 fine particles were discussed 相似文献
103.
Biomarker signature in tropical wetland: lignin phenol vegetation index (LPVI) and its implications for reconstructing the paleoenvironment 总被引:7,自引:0,他引:7
Organic matter of a peat core (3.60 m, 7428 years BP) collected from Rawa Danau, west Java, Indonesia, was analyzed to evaluate the early diagenetic fates of lignin in a tropical wetland and to reconstruct past vegetation and climate changes. Vertical profiles of (Ad/Al)v, (Ad/Al)s, and lambda(8) show that the lignin composition is well preserved in a sub-aqueous environment under reducing conditions. The sedimentary terrigenous plant material at Rawa Danau is comprised predominantly of angiosperm wood. For this kind of tropical, diverse, and dynamic ecosystem, a new vegetation change index called lignin phenol vegetation index (LPVI): LPVI is defined using the lignin phenol composition. This index can sensitively detect terrestrial vegetation changes as well as environmental conditions forcing such changes. The LPVI of the Rawa Danau peat core provides better resolution than other lignin parameters used previously, and reveals four major vegetation change events since the mid-late Holocene. In comparison to other geochemical data (i.e. elemental carbon, isotopes, and hydrocarbons), the LPVI is more sensitive and is able to trace even minor vegetation and climate changes and thus could improve biogeochemical interpretations of peat records. 相似文献
104.
Koji Morita Shuai Zhang Seiichi Koshizuka Yoshiharu Tobita Hidemasa Yamano Noriyuki Shirakawa Fusao Inoue Hiroaki Yugo Masanori Naitoh Hidetoshi Okada Yuichi Yamamoto Masashi Himi Etsujo Hirano Sensuke Shimizu Masaya Oue 《Nuclear Engineering and Design》2011,241(12):4672-4681
A five-year research project has been initiated in 2005 to develop a code based on the MPS (Moving Particle Semi-implicit) method for detailed analysis of key phenomena in core disruptive accidents (CDAs) of sodium-cooled fast reactors (SFRs). The code is named COMPASS (Computer Code with Moving Particle Semi-implicit for Reactor Safety Analysis). The key phenomena include (1) fuel pin failure and disruption, (2) molten pool boiling, (3) melt freezing and blockage formation, (4) duct wall failure, (5) low-energy disruptive core motion, (6) debris-bed coolability, and (7) metal–fuel pin failure. Validation study of COMPASS is progressing for these key phenomena. In this paper, recent COMPASS results of detailed analyses for the several key phenomena are summarized. Simulations of GEYSER and THEFIS experiments were performed for dispersion and freezing behaviors of molten materials in narrow flow channels. In particular, the latter experiment using melt–solid mixture is also related to fundamental behavior of low energy disruptive core. CABRI-TPA2 experiment was simulated for boiling behavior of molten core pool. Expected mechanism of heat transfer between molten fuel and steel mixture was reproduced by the simulation. Analyses of structural dynamics using elastoplastic mechanics and fracture criteria were performed for SCARABEE BE+3 and CABRI E7 experiments. These two analyses are especially focused on thermal and mechanical failure of steel duct wall and fuel pin, respectively. The present results demonstrate COMPASS will be useful to understand and clarify the key phenomena of CDAs in SFRs in details. 相似文献
105.
Ascorbic acid is used in apple juice as an antibrowning agent. This study investigated the effect of ascorbic acid (0.0–0.2% w/v) on the odours of cloudy apple juice using sensory evaluation and gas chromatography (GC). The increase in ascorbic acid concentration in the apple juice resulted in increases in green and unnatural odours and decreases in fresh, fruity and apple-like odours. In the GC determination, 23 volatile compounds were detected in apple juice. Aroma value, which showed the relative importance of volatile compounds, was used to elucidate the changes in odours of apple juice due to the addition of ascorbic acid. The aroma values of hexanal and trans-2-hexenal in the apple juice with 0.2% w/v ascorbic acid increased about 4 and 5-fold from those in the ascorbic acid-free apple juice, respectively. On the other hand, the aroma values of esters insignificantly changed in the apple juice with ascorbic acid. The increases in aroma values of aldehydes corresponded well with the increase in green odour in the apple juice with ascorbic acid. 相似文献
106.
Nakamura Noriyuki; Watanabe Sota; Betsuyaku Toru; Fujita Kazuo 《Canadian Metallurgical Quarterly》2010,124(3):331
Whereas many mammals (some primates and mice) experience amodal completion, previous data split for avian species. However, experimental procedures have been quite different among the species, and thus a direct comparison of various avian species in the same experimental situation is needed. We tested whether bantams (Gallus gallus domesticus) would complete partly occluded figures using a visual search task on the touch monitor, which was successfully used in our previous study with pigeons. First, we trained 3 participants to search for a notched red diamond (a target) among complete diamonds (distracters). Next, white squares accompanied each figure with a small gap of a fixed size. In test, the location of the accompanying white squares sometimes changed. In some trials, the white squares exactly covered, or “occluded,” the notched portion of the target. Humans are known to have great difficulty in finding such targets due to “automatic” completion of the notched part. However, bantams met no such difficulty at all. This result and the demonstration by Forkman (1998) of hens' amodal completion of figures placed on a perspective background, suggest that the perspective cue may have an important role in amodal completion in this species. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
We investigated an easy way to prepare industrially a conductive paint made with polyaniline (PANI)/dodecylbenzenesulfonic acid (DBSA) dispersion and poly(methyl methacrylate) (PMMA) in organic media. First, water‐dispersible PANI doped with DBSA was chemically synthesized with aniline sulfate using ammonium persulfate in water, and the resulting PANI/DBSA was readily extracted from the reaction medium with a mixture of toluene and methyl ethyl ketone (MEK) (toluene:MEK = 1:1 (v/v)), which is useful for industrial applications. The obtained PANI/DBSA organic dispersion was mixed with PMMA organic solution to give the corresponding PANI/DBSA conductive paint containing PMMA. A film prepared with the resulting PANI/DBSA conductive paint was found to possess relatively good conductivity and low surface resistivity for a conductive paint utilized for an electrostatic discharge even at low PANI/DBSA content in the PANI/DBSA–PMMA composite film (the conductivity and the surface resistivity were 9.48 × 10?4 S cm?1 and 3.14 × 106 Ω cm?2, respectively, when the feed ratio of PANI/DBSA:PMMA was 1:39 (w/w)). Furthermore, it was found that the conductivity of the film composed of PANI/DBSA–PMMA composite can be readily and widely controlled by the PANI/DBSA content of the composite or by the amount of DBSA used during the PANI/DBSA synthesis. The highest conductivity of PANI/DBSA–PMMA composite film (7.84 × 10?1 S cm?1) was obtained when the feed ratio of PANI/DBSA:PMMA was 1:4 (w/w). Copyright © 2007 Society of Chemical Industry 相似文献
108.
利用神经学统计图像分析软件NEUROSTAT分析健康志愿者和逼尿肌过度活动患者的SPECT图像,探讨膀胱贮尿的大脑控制区及其控制机理。15例健康志愿者(Ⅰ组)和25例下尿道尿储存功能障碍患者接受了SPECT扫描。25例中19例患者为逼尿肌过度活动症(Ⅱ组),6例患者逼尿肌功能正常(Ⅲ组)。所有受检者均在排空膀胱的静息状态和控尿状态接受SPECT扫描。控尿状态的图像用第二次扫描后的图像减去第一次的图像获得。用NEUROSTAT对比分析3组受检者在静息状态下的脑血流(rCBF)情况及各组受检者控尿状态与静息状态rCBF的差异,进行多重对照校正。静息状态下Ⅱ组与Ⅲ组相比脑血流差异无统计学意义(P〉0.05)。Ⅰ组和Ⅲ组控尿状态与静息状态相比,两侧额下回和右侧颞中回rCBF明显增高,其中右侧额下回在Z-值和病灶范围方面均最为明显(多重对照校正P〈0.05,工组对应Z-值〉4.476,Ⅲ组对应二值〉4.414)。Ⅱ组控尿状态与静息状态相比,仅左侧颞中回和额中回rCBF明显增高(多重对照校正P〈0.05,Ⅱ组对应Z-值〉4.35)。3组结果中,没有任何病灶脑血流降低达统计学标准。本研究结果表明两侧额下回和右侧颞中回与膀胱贮尿功能的大脑控制有关,特别是右侧额下回在膀胱贮尿的大脑控制中起重要作用,抑制控尿期逼尿肌的收缩。 相似文献
109.
Kazumasa Nomoto Nobuhide Yoneya Nobukazu Hirai Iwao Yagi Noriyuki Kawashima Makoto Noda Jiro Kasahara 《Journal of the Society for Information Display》2007,15(7):491-499
Abstract— Organic TFTs (OTFTs) have been developed with a novel solution‐processed gate insulator of poly(4‐vinylphenol) (PVP) with the addition of octadecyltrichloro‐silane (OTS) and a solution‐processed organo‐silver electrode/wire to improve the performance of an OTFT and to maked high‐throughput‐manufacturing process possible. Solution‐processed PVP has also employed for a buffer layer on a plastic substrate. The OTFT backplane with these solution‐based organic‐material technologies has been successfully applied to drive a 2.5‐in. QQVGA (160 × 120 pixels) AMLCD with a resolution of 79 dpi. 相似文献
110.
Noma S Kajiyama D Igura N Shimoda M Hayakawa I 《International journal of food microbiology》2006,109(1-2):103-108
The tailing in pressure inactivation curve of clinically isolated Escherichia coli O157:H7 was investigated. A typical tailing was observed after the treatment period for 30min when 10(7) CFU/ml of the cell suspension was subjected to pressure treatment at 300MPa and 25 degrees Celsius. There was no effect on the tailing profiles by the addition of pressure-killed cells and released cellular components. When cells survived at a tail portion were re-propagated (tail-culture) and subjected to second pressure treatment, the cells of the tail-culture exhibited eminently higher barotolerance compared to those of the original-culture, suggesting that the presence of genetically pressure-resistant subpopulation was responsible for the tailing. The cytoplasmic membrane of the tail-culture cells had higher stability to a pressure treatment at 100MPa for 10min than that of the original-culture, which was evidenced by lower permeability to ethidium bromide. The addition of non-ionic surfactants including 0.5microl/ml polyoxyethylene p-t-octylphenyl ester (Triton X-100) and 0.53mg/ml lauric sugar ester dramatically reduced the level of tailing and made the inactivation curve linear. 相似文献