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排序方式: 共有513条查询结果,搜索用时 15 毫秒
1.
A highly transparent and thermally stable copolymer of 1‐adamantyl methacrylate and styrene
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Thermal and optical properties of copolymers of 1‐adamantyl methacrylate (AdMA) and styrene (St) prepared by free radical polymerization in the bulk are investigated. The copolymer forms an azeotrope when the composition is AdMA/St = 55/45 mol%. The glass transition temperature and decomposition temperature of the azeotropic copolymer are 170 and ca 340 °C, respectively. The refractive index increases nonlinearly with St content from 1.522 to 1.591. The light scattering loss at 633 nm is 28.1 dB km?1, which is less than half of that of polystyrene. The total optical loss including molecular vibrational absorption, which is evaluated using a copolymer‐based optical fiber, is 292–645 dB km?1 at 500–700 nm. These values correspond to transmittances of 86–93% for a 1 m optical path length. © 2014 Society of Chemical Industry 相似文献
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Titanium Dioxide, TiO2, is a photocatalyst with a unique characteristic. A surface coated with TiO2 exhibits an extremely high affinity for water when exposed to UV light and the contact angle decreases nearly to zero. Inversely, the contact angle increases when the surface is shielded from UV. This superhydrophilic nature gives a self-cleaning effect to the coated surface and has already been applied to some construction materials, car coatings and so on. We applied this property to the enhancement of boiling heat transfer. An experiment involving the pool boiling of pure water has been performed to make clear the effect of high wettability on heat transfer characteristics. The heat transfer surface is a vertical copper cylinder of 17 mm in diameter and the measurement has been done at saturated temperature and in a steady state. Both TiO2-coated and non-coated surfaces were used for comparison. In the case of the TiO2-coated surface, it is exposed to UV light for a few hours before experiment and it is found that the maximum heat flux (CHF) is about two times larger than that of the uncoated surface. The temperature at minimum heat flux (MHF) for the superhydrophilic surface is higher by 100 K than that for the normal one. The superhydrophilic surface can be an ideal heat transfer surface. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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Tsukude M. Arimoto K. Hidaka H. Konishi Y. Hayashikoshi M. Suma K. Fujishima K. 《Design & Test of Computers, IEEE》1993,10(2):6-12
Two testing techniques for ultra-large-scale integrated (ULSI) memories containing on-chip voltage downconverters (VDCs) are described. The first in an on-chip VDC tuning technique that adjusts internal VCC to compensate for the monitored characteristics of the process parameters during repair analysis testing. The second is an operating-voltage margin test, performed at various internal VCC levels during the water sort test (WT) and the final shipping test (FT) 相似文献
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N Mamiya JR Goldenring Y Tsunoda IM Modlin K Yasui N Usuda T Ishikawa A Natsume H Hidaka 《Canadian Metallurgical Quarterly》1993,195(2):608-615
A novel Ca2+/calmodulin-dependent protein kinase II (CaM Kinase II) inhibitor, KN-93 potently inhibits gastric acid secretion from parietal cells. As previously reported (1), treatment of parietal cells with a selective inhibitor of CaM kinase II, KN-62 resulted in the inhibition of cholinergic-stimulated rabbit parietal cell secretion, whereas it failed to inhibit the histamine and forskolin response. In contrast effects of carbachol, histamine and forskolin were significantly inhibited by KN-93 with an IC50 of 0.15, 0.3 and 1 microM, respectively; these effects occurred without any changes in intracellular cyclic AMP and Ca2+ levels. In the present study we investigated the mechanism by which KN-93 acts upon the acid-secreting machinery of gastric parietal cells. Neither redistribution of the proton pump activity nor the morphological transformation were affected by KN-93. The drug only weakly inhibited the H+, K(+)-ATPase activity but strongly dissipated the proton gradient formed in the gastric membrane vesicles and reduced the volume of luminal space. Thus KN-93 acts at pH gradient formation whereas KN-62 acts only at CaM Kinase II. 相似文献
6.
Reuse of wastewater is regarded as one important way to deal with the world's shortage of potable water. The authors focused on a disinfection system using micro-bubbles and evaluated its capability for wastewater reuse. This paper reports experimental results from examination of the basic characteristics of micro-bubbles and disinfection of secondary effluent by air or ozone micro-bubbles. The results suggest that when micro-bubbles are applied in an ozonation system it is possible to reduce the reactor size, the amount of ozone decomposition equipment needed and the ozone dose rate. 相似文献
7.
Toshimitsu Suzuki Osamu Yamada Yasuhiko Takahashi Yoshihisa Watanabe 《Fuel Processing Technology》1985,10(1):33-43
Hydroliquefaction of low-sulfur Australian coals (Wandoan and Yallourn) was studied using iron carbonyl complexes as catalyst. The addition of Fe(CO)5 (2.8 wt% Fe of coal) increased coal conversion from 48.6 to 85.2% for Wandoan coal, and from 36.7 to 69.7% for Yallourn coal in 1-methylnaphthalene at 425°C under an initial hydrogen pressure of 50 kg cm?2. When molecular sulfur was added to iron carbonyls (Fe(CO)5, Fe2(CO)9 and Fe3(CO)12), higher coal converions ( > 92%) and higher oil yields (>46%) were obtained, along with an increase in the amount of hydrogen transferred to coal from the gas phase (0.2 to 2.8%, d.a.f. coal basis). In the liquefaction studies using a hydrogen donor solvent, tetralin, Fe(CO)5S catalyst increased the amount of hydrogen absorbed from the gaseous phase and decreased the amount of naphthalene dehydrogenated from tetralin. The direct hydrogen transfer reaction from molecular hydrogen to coal fragment radicals seems to be a major reaction pathway. Organic sulfur compounds, dimethyldisulfide and benzothiophene, and inorganic FeS2 and NiS were found to be good sulfur sources to Fe(CO)5. From X-ray diffraction analyses of liquefaction residues, it is concluded that Fe(CO)5 was converted into pyrrhotite (Fe1?xS) when sulfur was present, but into Fe3O4 in the absence of sulfur. 相似文献
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This paper introduces the Precise Rendering Method, which generates accurately anti-aliased and highlighted images from tessellated polygons. The Precise Rendering Method first solves the aliasing problems of hidden surface removal by using the Cross Scanline Algorithm. This algorithm can exactly calculate polygon areas projected onto each pixel by using horizontal and vertical scanlines. Aliasing artifacts in shading are then prevented by the Reflection Intergration Method, which analytically integrates the intensity of reflection in the solid angle defined by surface normals at vertices of the projected area. Several synthesized images are created to show the efficiency of the Precise Rendering Method. 相似文献
10.
Na-oyoshi Iwasaki Takanori Miyake Eriko Yagasaki Toshimitsu Suzuki 《Catalysis Today》2006,111(3-4):391-397
Attention has been increasingly paid to the partial oxidation of lower alkanes to synthesis gas, due to its intrinsic energy saving process. We studied the partial oxidation of ethane (POE) on Co loaded on various supports. The POE performance varied as follows: Y2O3, CeO2, ZrO2, La2O3 SiO2, Al2O3, TiO2 > MgO. Comparing Y2O3 and CeO2, the carbon deposition during the POE was negligible on CeO2 and therefore CeO2 was the most preferable support. By changing space velocity and O2 partial pressure, reaction mechanism of POE was studied and it was revealed that two-step mechanism was prevailing; combustion of ethane to H2O and CO2 and subsequent reforming of ethane with H2O and CO2 to synthesis gas. Co/CeO2 catalyst exhibited high and stable catalytic activity for 10 h; high ethane conversion of 18% (maximum ethane conversion 20% at O2/C2H6 = 0.2) with H2 and CO selectivities of 93 and 84%, respectively. 相似文献