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991.
采用溶胶凝胶方法制备了具有纳米尺度和多孔特征的氧化钌超电容器活性材料,探讨了烧结温度对电极材料的晶体结构,颗粒大小及电化学特性的影响.结合热失重分析、扫描电镜、循环伏安测试等方法探讨了溶胶凝胶法制备钌产物的组成及在高温条件下发生的分解过程和相应产物.钌氧化物材料经过210℃烧结处理后具有541 F/g的电化学容量,由其组成的超电容器具有67 J/g的能量密度.采用高导电乙炔黑作为载体制备了氧化钌/乙炔黑复合电极材料,当乙炔黑含量为10%时,电极材料的比容量达到802 F/g,采用该电极材料组成的电化学电容器具有100 J/g的能量密度且表现了良好的高功率放电特性. 相似文献
992.
Applying Parikh’s semi-classical tunneling method, Hawking radiation of charged massive particles via tunneling from charged
spherical black hole in vacuum for Vector Graviton Metric theory (VGM) of gravitation is investigated. Because the derivation
respects conservation of energy and charge, the tunneling rate of particles is relevant to the change of Bekenstein-Hawking
entropy and the exact spectrum is not precisely thermal. The result employs an underlying unitary theory.
PACS numbers: 04.70.-s, 97.60. Lf 相似文献
993.
References: 《理论物理通讯》2007,47(6):1145-1147
We extend Zhang and Zhao's recent work to the Schwarzschild-anti-de Sitter black hole with topological defect, whose Arnowitt-Deser-Misner (ADM) mass is no longer identical to its mass parameter. The behavior of the tunneling massive particle is investigated and the emission rate is calculated. The result satisfies an underlying unitary theory and takes the same functional form as that of the mass-less particle. 相似文献
994.
Micropatterned layer‐by‐layer (LbL) assemblies were studied as a potential platform for sensor applications by performing impedance characterization throughout a range of electrolyte concentrations. Conductive LbL thin films were prepared with carbon black nanoparticles dispersed in the polymer matrix to provide an electrically conductive network. LbL assemblies were micropatterned using a photolithographic lift‐off method, and a test circuit was constructed as multiple interdigitating coplanar electrodes. Impedance spectra were collected between 104 and 106 Hz within a flow cell containing NaCl solutions ranging from 0.001–1.0 M. These preliminary results demonstrate the ability to pattern conductive LbL composites and underscore the potential utility and shortcomings of their use in sensor applications. 相似文献
995.
996.
计算了广义球对称含荷黑洞视界上标量场的量子态数和自由能,得到了黑洞熵与视界面积成 正比的结论,表明黑洞熵就是其视界上的量子态的熵.考虑广义不确定原理对黑洞熵的影响 ,采用二维膜模型,克服了brick-wall模型中的发散困难,计算中无须任何截断,且brick- wall模型中的小质量近似也可以避免.对视界外二维膜上的量子场的熵做了级数展开讨论, 得到了一些值得探讨的结论.
关键词:
广义不确定原理
黑洞熵
视界
截断 相似文献
997.
孙鸣超 《数学物理学报(A辑)》2005,25(1):67-72
在Tortoise坐标系中,利用brick wall模型研究了电磁场对Vaidya Bonner de Sitter黑洞熵的量子修正. 当黑洞事件视界不随超前时间变化时,结果与Reissner Nordstrom de Sitter黑洞的量子熵完全相同. 相似文献
998.
Catalytic decomposition of hydrogen peroxide by a flow-through self-regulating platinum black heater
Norio Teshima 《Analytica chimica acta》2004,510(1):9-13
A flow-through reactor where a fine platinized platinum wire (Pt black wire) runs through the entire length of the PTFE tube was fabricated for the rapid decomposition of hydrogen peroxide (H2O2) at concentrations up to 1 M. Since the Pt black wire is directly electrically heated and the exterior of the tubular reactor is well insulated, the energy efficiency of this heater reactor is excellent. The temperature coefficient of resistance of the wire is significant (3280±40 ppm/°C). This provides a means to ascertain the mean temperature by measuring the resistance of the wire. The concentration of residual H2O2 was determined by the hematin-catalyzed oxidation of nonfluorescent thiamine to fluorescent thiochrome by H2O2. Essentially, quantitative (99.997%) decomposition of 1 M H2O2 could be achieved at a mean reactor temperature of 108 °C from a neutral aqueous solution with a mean residence time of ∼270 s. 相似文献
999.
1000.
Masaru Shibata 《Pramana》2004,63(4):703-715
I describe the current status of numerical relativity from my personal point of view. Here, I focus mainly on explaining the
numerical implementations necessary for simulating general relativistic phenomena such as the merger of compact binaries and
stellar collapse, emphasizing the well-developed current status of such implementations that enable simulations for several
astrophysical phenomena. Some of our latest results for simulation of binary neutron star mergers are briefly presented. 相似文献