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61.
SJ Kim T Ishibashi H Saito S Maruoka S Higano A Sato S Takahashi S Yamada H Hama K Koyama T Mitomo 《Canadian Metallurgical Quarterly》1998,58(3):94-96
This communication describes one pediatric neurosurgeon's personal view of the neurosurgical perspectives in pediatric neurooncology. Various roles of surgery, including histological verification, maximum cytoreduction, neurodecompression and restoration of the cerebrospinal fluid pathway, are emphasized. A pediatric neurosurgeon, who is the first person to make decisions on diagnosis and treatment relating to children with brain tumors, should be up to date with advances in diagnostic and therapeutic methods. Particularly, he or she should be familiar with both the efficacy and the side effects of radiation therapy and chemotherapy to allow selection of the optimum treatment for such children. 相似文献
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Determination of citric acid and its decomposed products in edible oils by gas liquid chromatography 总被引:1,自引:0,他引:1
A quantitative gas liquid chromatographic (GLC) method for four organic acids-citric, aconitic, itaconic, and citraconic acids-in
refined oils and fats was developed. After the organic acids are extracted with water from soybean oils, the extract is esterified
with n-butanol and an aliquot of the ester is subjected to GLC on a temperature-programmed 10% DEGS column equipped with a
flame ionization detector. At 20 and 30 ppm levels, recoveries of the acids from the oil varied from 95 to 100% except for
itaconic acid. Citric acid content in commercial edible oils in Japan was from trace to 16 ppm. However, aconitic, itaconic,
and citraconic acids were not detected. 相似文献
65.
Carbon deposition from the cracking of methane into the pores of a lignite char occurs at a significant rate at temperatures between 815 and 855 °C. The maximum amount of carbon deposited is much less than the amount of open pore volume within the char which is potentially available to accommodate carbon. Removal of the inorganic impurities from the char by acid washing significantly reduces the extent of carbon deposition. Carbon deposition reduces surface area and open pore volume of the char and accessibility of methane into the pore structure. Deposition of carbon has a large and lasting adverse effect on the subsequent reactivity of the char to air. This has been attributed both to a decrease in active surface area, and deactivation of catalytic inorganic impurities due to coating with carbon. Deposited carbon is much less reactive to air than the lignite char. Results indicate that in order to maximize subsequent char reactivity to oxidizing gases, carbon deposition from volatiles during the conversion of coal to char should be kept to a minimum. 相似文献
66.
Jadambaa Temuujin Mamoru Senna Tsedev Jadambaa Dashdendev Burmaa Shaarii Erdenechimeg Kenneth JD MacKenzie 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2006,81(4):688-693
After being subjected to preliminary purification, montmorillonite clay was leached with varying concentrations of sulfuric acid (0.5–2 mol L?1) at 90 °C for varying times (0.5–4 h). Acid leaching causes partial amorphization of the montmorillonite and increases its specific surface area by a factor of 3 (from 49.1 to 157 m2 g?1). The bleaching efficiency for Mongolian mare's milk oil, as judged by light absorbance measurements at 400 nm, was increased from 9.5% for the unleached clay to 93.8% for clay leached with 2 mol L?1 H2SO4 for 4 h. Copyright © 2006 Society of Chemical Industry 相似文献
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The 13C NMR and Fourier transform infrared (FTIR) spectra of an electrochemically prepared polythienylene film have been obtained. The polythienylene film displays only two sharp absorption bands, at 124.8 and 136.5 ppm downfield from TMS (tetramethylsilane) in the 13C NMR, these being attributable to the carbon atoms in the β-position and the α-position, respectively, relative to the sulfur atom of poly(2,5-thienylene). The polythienylene film also shows a sharp absorption band at 789 cm?1 in the IR, which is definitely ascribable to the C-H out-of-plane vibration of poly(2,5-thienylene). The polythienylene film will be shown to have a highly defined structure with a dominance of poly(2,5-thienylene). 相似文献
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Most of the emerging content-based multimedia technologies are based on efficient methods to solve machine early vision tasks. Among other tasks, object segmentation is perhaps the most important problem in single image processing. The solution of this problem is the key technology of the development of the majority of leading-edge interactive video communication technology and telepresence systems. The aim of this paper is to present a robust framework for real-time object segmentation and tracking in video sequences taken simultaneously from different perspectives. The other contribution of the paper is to present a new dedicated parallel hardware architecture. Its composed of a mixture of Digital Signal Processing (DSP) and Field Programmable Gate Array (FPGA) technologies and uses the Content Addressable Memory (CAM) as a main processing unit. Experimental results indicate that small amount of hardware can deliver real-time performance and high accuracy. This is an improvement over previous systems, where execution time of the second-order using a greater amount of hardware has been proposed.Mahmoud Meribout (BS85, M91). Received the PhD degree in Electronic Engineering from the University of Technology of Compiegne (France), in January 3rd 1995. He worked one year as an Associate Researcher, where he has been involved in some industrial projects related to hardware board design and video processing. FromNovember 1995 to October 2000, he has beenworking in Japan, with NTT and NEC corporations respectively, where he has been involved in several projects related to hardware & software design of next generation multimedia and networking equipments. He is holding several Japanese and American patents related to this particular topic. In 1998, he has received the NTT best award for his research and development records.Maamouru Nakanishi received the B.S. and M.S. in Electronics in 1985 and 1987 respectively, all from Kyoto University. Since 1987, he has been engaged in R&D of parallel processing architectures, memory-processor integration technology at NTT Corporation (Tokyo, Japan), when he has been involved in research on Advanced Content Addressable Memory applied to video processing. In 1998, he has received the NTT best award for his research and development records. 相似文献