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11.
In the case of the wet coal charging process in coke oven chamber, it is known that the coking process is uneven and a local carbonization delay occurs. The reason was investigated through a laboratory-scale experiment and a quantitative estimation. A partial carbonization test in a test coke oven replicated the uneven plastic layer and local carbonization delay. It was revealed that most of the gas generated in the uncarbonized coal layer results from the evaporation of condensed water and that steam can break through the plastic layer in a test coke oven. Moreover, the order estimation implied that steam that generates in the uncarbonized coal layer and breaks through the plastic layer has sufficient heat capacity to cool the heating wall and delay the carbonization. It was also shown that the steam pressure peak measured in a commercial coke oven is much lower than the estimated steam pressure in this study assuming steam not breaking through the plastic layer. The above-mentioned results and quantitative investigation strongly support the ‘steam breaking through the plastic layer’ theory proposed by Dr. Rohde that an uneven carbonization process is caused by vaporized coal moisture breaking through the plastic layer at definite, unforeseeable points, which results in cooling of the wall by the steam flow. 相似文献
12.
Namsin Park Takeyuki Shiraishi Kazuyoshi Kamisugi Yoshitaka Hara Keita Iizuka Takashi Kado Shuzi Hayase 《Journal of Applied Electrochemistry》2008,38(3):371-375
A direct ethanol fuel cell (DEFC), which is less prone to ethanol crossover, is reported. The cell consists of PtRu/C catalyst as the anode, Nafion® 117 membrane, and Ni–Co–Fe (NCF) composite catalyst as the cathode. The NCF catalyst was synthesized by mixing Ni, Co, and Fe complexes into a polymer matrix (melamine-formaldehyde resins), followed by heating the mixture at 800 °C under inert atmosphere. TEM and EDX experiments suggest that the NCF catalyst has alloy structures of Ni, Co and Fe. The catalytic activity of the NCF catalyst for the oxygen reduction reaction (ORR) was compared with that of commercially available Pt/C (CAP) catalyst at different ethanol concentrations. The decrease in open circuit voltage (Voc) of the DEFC equipped with the NCF catalysts was less than that of CAP catalyst at higher ethanol concentrations. The NCF catalyst was less prone to ethanol oxidation at cathode even when ethanol crossover occurred through the Nafion®117 film, which prevents voltage drop at the cathode. However, the CAP catalyst did oxidize ethanol at the cathode and caused a decrease in voltage at higher ethanol concentrations. 相似文献
13.
14.
A case of 22-year-old man suffering from ulcerative colitis, in whom Weber-Christian panniculitis and musculitis occurred simultaneously, is reported. He had suffered from ulcerative colitis for 7 years and he again had bloody stools 1 month before being admitted. Two weeks before admission, large (2-4 cm) subcutaneous tumors appeared. Weber-Christian panniculitis, musculitis, and active stage ulcerative colitis were diagnosed. All the symptoms went into remission after steroid therapy. The possibility of the existence of a common antigen in enterobacterial wall, colonic epithelium, and adipose tissue was suggested. 相似文献
15.
16.
Temperature dependences of the soft phonon frequency and the damping constant in Tris-Sarcosine Calcium Chloride (TSCC) single crystal have been investigated between 5K and 100K by using a Fourier-transform far-infrared spectrometer. It has been observed that the soft phonon frequency decreases gradually and the damping constant increases as the transition temperature is approached from below The damping constant varies from 7cm-1 a 90K to less than 0.5cm-1 at 5K. It has been found that the damping constant is approximately proportional to temperature below about 60K. 相似文献
17.
高速气流冲击式粉体表面改性装置——HYBRIDIZATION系统及应用 总被引:4,自引:0,他引:4
利用高速气流冲击法进行粉体/粉体系表面改性技术,是迄今为止各种粉体材料开发中最为引人注目的技术之一。HYBRIDIZATION(下称HYB)系统是利用高速气流冲击法对微粉体进行干式/机械化处理,是使材料复合化的最实用的装置,可对各类有机物、无机物、金属等进行广泛组合,通用性很强,适用于许多行业领域。从本文所述的系统构成、型式,有关的典型球形化处理的运转特性,利用复合化高温粉体测定被处理粉体表面温度,利用颜料改变色调等的处理特点及该系统的适用性等(一部分是从已发表的学术论文及专利上摘录的),可以说明HYB系统的概况。 相似文献
18.
Takashi Mitamura Hiroyuki Ogino Hidehiko Kobayashi Toshiyuki Mori Hiroshi Yamamura 《Journal of the American Ceramic Society》1993,76(8):2127-2128
Preparation of BaLa2 O4 , Ba3 ,Y4 O9 , Ba ,In2 O5 , and Ba3 Ga2 O6 powders and their sintering were investigated in Ar or air. These sintered bodies with perovskite-related structure were synthesized by reaction sintering, using mixed powders in the atomic ratios of Ba/La = 1, Ba/Y = 0.75, Ba/In = 1, and Ba/Ga = 1.5. The order-disorder transition temperatures of the BaLa2 O4 , Ba3 Y4 O9 , Ba2 In2 O5 , and Ba3 Ga2 O6 sintered bodies were 270°, 350°, 880°, and 123Oo C, respectively. It was found that the temperatures were influenced by the ionic radius of cations in B sites, and the transition temperatures decreased with increasing ionic radius. 相似文献
19.
Takeo Tokiai Takashi Uesugi Kunihito Koumoto 《Journal of the American Ceramic Society》1995,78(4):1089-1092
High thermoelectric figure of merit semiconducting ceramics of n -type iron disilicide with modified local compositions have been developed. Sintering and annealing of the composite powder composed of iron disilicide and precipitated cobalt (II) hydroxide resulted in the dissolution of excess Co and oxygen into the iron disilicide phase. Excess Co segregated to the grain boundary region, while interstitially incorporated oxygen was distributed homogeneously in the microstructure. The maximum figure of merit achieved was 5.2 × 10−4 /K at 673 K. 相似文献
20.
Takashi Nakamura 《Lipids》1986,21(9):553-557
Prostaglandin-like substances other than 3-(2-ethyl-5-hydroxy-3-oxo)-cyclopentanyl-2-propenal (compound I), which upon reacting
with amino acids form reddish pigments, were purified, and their chemical structures were determined. Three red pigment-forming
substances (RPS) in autoxidized methyl linolenate were purified successively by gel chromatography on Sephadex LH-20, column
chromatography and thin layer chromatography on Silica Gel 60, and by high performance liquid chromatography on μ-Porasil.
IR spectra of the RPS showed the absorption of an ester group (νC=O 1730 cm−1 in CHCl3) and of a longer branched chain (νC-H 2800–3100 cm−1), in addition to the absorption bands observed in compound I. Electron impact mass spectra of the trimethylsilyl ethers obtained
after reduction with NaBH4 and NaBD4 were analyzed in detail and compared with those of compound I. The structures of the RPS were identified as stereoisomeric
methyl 8-[2-(2-formylvinyl)-3-hydroxy-5-oxo-cyclopentanyl]-octanoates derived from methyl 12-hydroperoxy-linolenate.
Presented at the general meeting of the Japanese Society of Scientific Fisheries, held at Tohoku University, Sendai, Japan,
October 1984. 相似文献