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排序方式: 共有484条查询结果,搜索用时 15 毫秒
81.
为解决抚顺石化公司石油三厂连续重整装置原料短缺的问题,根据实际的工况条件,在小型试验装置上详细研究了大庆常压塔顶汽油脱砷脱氯工艺技术的可行性,并对几种脱砷脱氯工艺方案进行了论证。试验结果表明,通过对现有脱氯反应器的改造,采用脱砷-脱氯联合工艺技术,可将大庆常压塔顶汽油中的砷从1000ng/g以上脱除至10ng/g以下,氯从5μg/g以上脱除至0.5μg/g以下,循环气中的HCl小于1μg/g,完全满足连续重整装置工况的要求。对脱砷-加氢-脱氯汽油中碱金属和碱土金属的测定结果表明,不存在催化剂的金属流失问题。预计该工艺可为企业带来直接经济效益560万元/a。 相似文献
82.
Tamaki Shibayama Guo Wei He Heishichiro Takahashi Yutai Katoh Akira Kohyama 《北京科技大学学报(英文版)》1999,6(2)
LowZmaterialshavemanyadvantagesinnuclearenvirOInnellts,suchaslessProductionofradioactivewastesduetosubstantiallylowactivation,andhigherconVergentefficiencyduetothecapabilityofhightemp~OPeration.HopkinhasdiscussedSiC-basedmaterialsforfhaionreactorsfor... 相似文献
83.
Robles R Lorente N Isshiki H Liu J Katoh K Breedlove BK Yamashita M Komeda T 《Nano letters》2012,12(7):3609-3612
Being able to control the spin of magnetic molecules at the single-molecule level will make it possible to develop new spin-based nanotechnologies. Gate-field effects and electron and photon excitations have been used to achieve spin switching in molecules. Here, we show that atomic doping of molecules can be used to change the molecular spin. Furthermore, a scanning tunneling microscope was used to place or remove the atomic dopant on the molecule, allowing us to change the molecular spin in a controlled way. Bis(phthalocyaninato)yttrium (YPc(2)) molecules deposited on an Au (111) surface keep their spin-1/2 magnetic moment due to the small molecule-substrate interaction. However, when Cs atoms were carefully placed onto YPc(2) molecules, the spin of the molecule vanished as shown by our conductance measurements and corroborated by the results of density functional theory calculations. 相似文献
84.
Banded structure and its distribution in friction stir processing of 316L austenitic stainless steel
Y.C. Chen H. Fujii T. Tsumura Y. Kitagawa K. Nakata K. Ikeuchi K. Matsubayashi Y. Michishita Y. Fujiya J. Katoh 《Journal of Nuclear Materials》2012,420(1-3):497-500
Banded structures, which vary with welding parameters, were observed in friction stir processing of 316L austenite stainless steel. Sigma phase precipitation was detected in banded structures by transmission electron microscopy. The amount of banded structure had direct ratio relations with heat input. The higher the heat input, the larger the area of banded structures. This is attributable to slower cooling rate at high heat input, which results in longer exposure to the temperature range for precipitation. The formation of sigma phase produced Cr depletion, which resulted in largely degraded corrosion resistance. The present study suggests that low heat input (i.e. low rotation speeds, low working loads and high welding speed) contributes to restrain sigma phase precipitation. 相似文献
85.
AbstractSolvent extracts were compared with the parent gelatins by means of TLC and HPLC. The photographic effects of the various protein fractions are discussed. 相似文献
86.
Yoshitaka Chikazawa Atsushi Katoh Hiroyuki Obata Masayuki Uzawa Kazuhiro Koga Ryo Chishiro 《Journal of Nuclear Science and Technology》2013,50(4):437-447
A simplified fuel handling system design for the demonstration Japan sodium-cooled fast reactor (JSFR) has been proposed. Fast Reactor Cycle Technology Development project phase I results of key technology evaluations on a pantograph fuel handling machine (FHM), a fuel transfer pot with two core component positions, dry spent fuel cleaning and minor actinide-bearing fresh fuel shipping cask are summarized. A full-scale FHM mockup has been fabricated and tested in the air accumulating performance and seismic tolerance data. A mockup fuel transfer pot with fins and chromium carbide coating has been fabricated and tested with sodium accumulating heat transfer performance data. Several sodium cleaning tests using a dummy subassembly has been conducted accumulating cleaning performance data. For fresh fuel shipping cask, a design tool for evaluation of heat transfer capability has been developed and a helium gas cask shows cooling capability of minor actinide-bearing fresh fuel. Those experimental and analytical efforts have shown that key technologies to develop simplified fuel handling system are matured enough to proceed large-scale sodium experiments and conceptual design study for the demonstration JSFR. 相似文献
87.
A theoretical and experimental study is conducted to investigate the detached volume from a pendant drop on the surface of a sphere. Observation of drop detachment by high‐speed video camera reveals that the movement of the upper part of the neck of the drop is quite slow compared to that of the detaching lower part. The surface profile of the upper part was calculated approximately as a static problem using the axisymmetric Laplace equation. Using the drop profile, the system energy, including the work done by the solid–liquid wetting behavior, was calculated. Based on the condition of minimum energy, the volume of the detached part V was calculated. The volume V increases with the sphere diameter and approaches the value for the pendant drop attached to a plate. In addition, V is strongly dependent on the wettability between the sphere and the liquid and decreases with the receding contact angle. The detached volume of the water drop was measured for spheres of porous brick of various diameters. The experimental and theoretical results were found to be in good agreement. © 2010 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/htj.20305 相似文献
88.
在柴油吸氧安定性能研究与评价的基础上 ,在 2 90~ 3 60K、0 .1 0~ 0 .2 5MPa氧压、无光照和Cu催化条件下详细考察了大庆直馏柴油 (SRDF)和焦化加氢柴油 (HCDF)吸氧速率和吸氧加速率的变化规律。研究结果表明 ,在给定的条件下柴油的吸氧速率 (vt)和吸氧加速率 (vtt)随时间的增长而逐渐减小 ,随氧压或温度的升高而迅速增大。温度和氧压越高或时间越长 ,vt 和vtt的变化幅度越大。vt 和vtt在短时间 (≤ 3 0h)或高氧压 ( >0 .1 5MPa)或高温 ( >3 3 0K)时的变化幅度较大 ,而在长时间 ( >3 0h)或低氧压 (≤ 0 .1 5MPa)或低温 (≤ 3 3 0K)时的变化幅度较小。HCDF的 (起始 )吸氧速率和 (起始 )吸氧加速率高于SRDF。两者在吸氧速率和吸氧加速率之间存在较大的区别。 相似文献
89.
在柴油吸氧安定性能研究与评价的基础上 ,在 2 90~ 3 60K、氧分压 0 .10~ 0 .2 5MPa、无光照和Cu催化条件下详细考察了温度和氧压对大庆直馏柴油 (SRDF)和焦化加氢柴油 (HCDF)吸氧氧化性能的影响。研究结果表明 ,在给定的时间和氧压或温度条件下随温度或氧压的升高 ,柴油的吸氧量 (Va)迅速增加 ;氧压或温度越高或时间越长 ,柴油的吸氧量越大 ;在短的吸氧时间下Va 的变化幅度较小 ,而在长的时间下Va 变化幅度较大 ;低温对SRDF的吸氧量影响较大 ,而高温对HCDF的吸氧量影响较显著 ;氧压对SRDF的吸氧量有较大的影响 ,而对HCDF的吸氧量影响较小 ;低温或高氧压下HCDF的Va 小于SRDF ,而在高温或低氧压下HCDF的Va 反而大于SRDF。柴油中含有某些不饱和烃、特别是共轭二稀烃、环烷芳香烃类等不安定组分的种类越多及含量越高 ,就越容易发生吸氧氧化反应 ,它们的安定性能或质量下降越明显 相似文献
90.
Electrical resistivity and thermopower of (La1−xSrx)MnO3 and (La1−xSrx)CoO3 at elevated temperatures
T. Ohtani K. Kuroda K. Matsugami D. Katoh 《Journal of the European Ceramic Society》2000,20(16):105-2726
Electrical resistivity and Seebeck (S) measurements were performed on (La1−xSrx)MnO3 (0.02x0.50) and (La1−xSrx)CoO3 (0x0.15) in air up to 1073 K. (La1−xSrx)MnO3 (x0.35) showed a metal-to-semiconductor transition; the transition temperature almost linearly increased from 250 to 390 K with increasing Sr content. The semiconductor phase above the transition temperature showed negative values of S. (La1−xSrx)CoO3 (0x0.10) showed a semiconductor-to-metal transition at 500 K. Dominant carriers were holes for the samples of x0.02 above room temperature. LaCoO3 showed large negative values of S below ca. 400 K, indicative of the electron conduction in the semiconductor phase. 相似文献