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101.
Test results of a catalytically assisted combustor for a gas turbine   总被引:1,自引:0,他引:1  
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.
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.
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.
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   
105.
This paper outlines the first Asian network-based speech-to-speech translation system developed by the Asian Speech Translation Advanced Research (A-STAR) consortium. Eight research groups comprising the A-STAR members participated in the experiments, covering nine languages, i.e., eight Asian languages (Hindi, Indonesian, Japanese, Korean, Malay, Thai, Vietnamese, and Chinese) and English. Each A-STAR member contributed one or more of the following spoken language technologies: automatic speech recognition, machine translation, and text-to-speech through Web servers. The system was designed to translate common spoken utterances of travel conversations from a given source language into multiple target languages in order to facilitate multiparty travel conversations between people speaking different Asian languages. It covers travel expressions including proper nouns that are names of famous places or attractions in Asian countries. In this paper, we describe the issues of developing spoken language technologies for Asian languages, and discuss the difficulties involved in connecting different heterogeneous spoken language translation systems through Web servers. This paper also presents speech-translation results including subjective evaluation, from the first A-STAR field testing which was carried out in July 2009.  相似文献   
106.
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.
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   
109.
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   
110.
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