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991.
本文研究荷能氢离子轰击对TiC薄膜的结构及其界面的影响。氢离子源为5A的脉冲离子注入器,能量25keV,脉冲宽度20ms。样品经轰击后发现。与受相同辐照的45~#钢样品相比,TiC薄膜表面无明显的损伤;TiC薄膜内的氢含量较高;薄膜的织构消除;TiC薄膜与基体间的结合力有明显提高。 相似文献
992.
Measurements of the maximum transmittance of an in-plane switching liquid crystal display showed that it increases as rubbing angle is increased from 10 to 20°. This dependence was analysed in terms of the local variation of electric field intensity between electrodes, which in turn makes liquid crystal at various positions between the electrodes rotate to different angles. The local variation of electric field becomes prominent, especially in the case that the distance between the electrodes is much larger than the cell gap or electrode width. 相似文献
993.
Phase‐pure ammonium catena‐polyphosphate IV [NH4PO3]x was synthesized by heating NH4H2PO4 in a tube furnace under an ammonia gas flow. The product contained single crystals of [NH4PO3]x IV appropriate for an X‐ray structure determination enabling structure refinement of this compound. The pseudo‐merohedrally twinned crystals of [NH4PO3]x crystallize in the monoclinic crystal system (P21/c, no. 14, a = 2270.3(5), b = 458.14(9), c = 1445.1(3) pm, β = 108.56(3)°, Z = 4, 2264 data, R1 = 0.076). In the unit cell the catena‐polyphosphate chain anions run parallel [010] with a chain‐periodicity P = 2 and a stretching factor fs = 0.94. The chain anions are interconnected through extensive hydrogen bonding towards the ammonium ions. Due to ‘chemical twinning’ a novel catena‐polyphosphate structure type is realized in [NH4PO3]x IV. The vibrational spectra of [NH4PO3]x IV are reported as well. 相似文献
994.
信息网络的传输宽带化和业务多样化需求给交换结构的可扩展性及性能提出了更高的要求.基于MSM(Memory-Space-Memory)输入输出排队交换结构进行研究,通过对交换网络内部拥塞调度机制进行深入分析,在保障调度公平性的基础上,提出一种严格匹配输出调度过程的SM-RR(Strict Matching algorithm based onRound-Robin)算法.与现有典型算法相比,该算法无需加速比即可获得较高的性能. 相似文献
995.
Zhenhua Li Ying Song Pa Du Xinbin Ma Baowei Wang Genhui Xu 《Reaction Kinetics and Catalysis Letters》2001,73(1):135-142
The kinetics of hydrolysis of tetrahydrozoline hydrochloride in aqueous solution at 353, 363 and 368 K in the pH-range from
2.00 to 12.20 has been investigated. The decomposition products have been investigated by HPLC.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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Abstract Using supercritical water oxidation, the cation exchange resin was decomposed fast and completely to water, carbon dioxide and sulfuric acid. While the resin decomposition yield increased with the reaction time and the amount of hydrogen peroxide added as oxidizing agent, it was constant in the resin concentration from 0.14 to 1.9 dry resin weight percent to water. More than 99% of the cation exchange resin was decomposed with hydrogen peroxide added in the amount of 7 times the stoichiometric value at 673 K and 30MPa for 30 minutes of the reaction time. The cation exchange resin is decomposed through two main reaction pathways. One has a rate controlling intermediate such as acetic acid whose decomposition rate was very slow, and the other does not have stable intermediates. The decomposition of the acetic acid is a significant factor for the complete decomposition of the resin, although it does not dominate the whole resin decomposition. A simple kinetic model that estimates the resin decomposition yield was developed. 相似文献
1000.
The calculations of the P-V isotherms, Hugoniots, dissociation and ionization degrees of fluid (liquid) hydrogen isotopes have been performed by using the self-consistent fluid variational theory under isothermal and shock compression. The isotope effect of fluid hydrogen was discussed. The present results are compared with the available experiments and calculations. 相似文献