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991.
992.
模拟海洋电极的使用环境,以电极的电化学反应过程为基础,介绍了电化学噪声的产生机理、影响因素及分类;对比分析了不同烧结温度下电极噪声性能的差异.结果显示,电极的微观结构和导电特性共同影响其噪声性能.研究表明,将烧结温度设在465℃附近烧制的电极的表面缺陷少、对电信号传导的影响低、噪声性能优,进而为电极的烧结工艺指出了方向. 相似文献
993.
Ja-Young Jung Shin-Bok Lee Ho-Young Lee Young-Chang Joo Young-Bae Park 《Journal of Electronic Materials》2009,38(5):691-699
Anodic dissolution and the electrochemical migration characteristics of eutectic Sn-Pb solder alloy in deaerated 0.001% NaCl
and Na2SO4 solutions were investigated using anodic polarization and water drop tests. Anodic polarization results revealed that a Pb-rich
phase was preferentially ionized in deaerated 0.001% NaCl solution and an Sn-rich phase was predominantly ionized in deaerated
0.001% Na2SO4 solution, which coincides well with the composition of the dendrites formed during water drop tests. X-ray diffraction and
photoelectron spectroscopy results showed that the surface oxide film formed on pure Sn in deaerated 0.001% NaCl solution
is more stable than that formed on pure Sn in deaerated 0.001% Na2SO4 solution. The surface oxide film formed on pure Pb in deaerated 0.001% Na2SO4 solution is more stable than that formed on pure Sn in deaerated 0.001% NaCl solution. Therefore, the quality of the surface
film of eutectic Sn-Pb solder in a chemical environment seems to be critical not only for corrosion resistance, but also for
electrochemical migration resistance. 相似文献
994.
Marc C. Necker 《Mobile Networks and Applications》2009,14(4):539-550
The currently emerging 802.16e (WiMAX) and 3GPP Long Term Evolution (LTE) cellular systems are based on Orthogonal Frequency
Division Multiple Access (OFDMA). OFDMA suffers from heavy inter-cell interference if neighboring base stations use the same
frequency range. One approach to solve this issue is the application of beamforming antennas in combination with interference
coordination (IFCO) mechanisms between base stations. In this paper, we trace the problem of IFCO back to the graph coloring
problem and investigate the achievable resource utilization of the interference coordinated system. We develop a heuristic
that allows the combination of arbitrary scheduling algorithms with the IFCO mechanism. This allows an efficient utilization
of the radio system’s frequency resources while still obeying scheduling constraints, such as Quality of Service requirements.
Finally, we study the tradeoff between fairness and the total system throughput.
相似文献
Marc C. NeckerEmail: |
995.
Xinliang Feng Yanyu Liang Linjie Zhi Arne Thomas Dongqing Wu Ingo Lieberwirth Ute Kolb Klaus Müllen 《Advanced functional materials》2009,19(13):2125-2129
One‐dimensional fibers and tubes are constructed through the oriented carbon‐carbon cross‐linking reactions towards rigid conjugated polymer networks. As the result, a template‐free and one‐step synthesis of CNTs and CNFs is achieved through a simple carbonization of the as‐formed carbon‐rich tubular and fiberlike polyphenylene precursors under argon. Microporous CNTs and CNFs with a surface area up to 900 m2 g–1 are obtained, together with HR‐TEM characterizations indicating the formation of intrinsic microporous structure in these rigid carbon‐rich networks. The primary electrochemical experiments reveal their promising applications as advanced electrodes in electrochemical double‐layered capacitor (EDLC). 相似文献
996.
Lei He Juan Qiao Lian Duan Guifang Dong Deqiang Zhang Liduo Wang Yong Qiu 《Advanced functional materials》2009,19(18):2950-2960
Using imidazole‐type ancillary ligands, a new class of cationic iridium complexes ( 1 – 6 ) is prepared, and photophysical and electrochemical studies and theoretical calculations are performed. Compared with the widely used bpy (2,2′‐bipyridine)‐type ancillary ligands, imidazole‐type ancillary ligands can be prepared and modified with ease, and are capable of blueshifting the emission spectra of cationic iridium complexes. By tuning the conjugation length of the ancillary ligands, blue‐green to red emitting cationic iridium complexes are obtained. Single‐layer light‐emitting electrochemical cells (LECs) based on cationic iridium complexes show blue‐green to red electroluminescence. High efficiencies of 8.4, 18.6, and 13.2 cd A?1 are achieved for the blue‐green‐emitting, yellow‐emitting, and orange‐emitting devices, respectively. By doping the red‐emitting complex into the blue‐green LEC, white LECs are realized, which give warm‐white light with Commission Internationale de L'Eclairage (CIE) coordinates of (0.42, 0.44) and color‐rendering indexes (CRI) of up to 81. The peak external quantum efficiency, current efficiency, and power efficiency of the white LECs reach 5.2%, 11.2 cd A?1, and 10 lm W?1, respectively, which are the highest for white LECs reported so far, and indicate the great potential for the use of these cationic iridium complexes in white LECs. 相似文献
997.
钌-邻菲咯啉配合物已经广泛应用于电化学、光化学领域,以羟基苯基并[4,5]-邻菲咯啉(Hpip)为配体,合成二氯化三羟基苯基并[4,5]-邻菲咯啉钌(Ru(Hpip)3Cl2)。应用红外、紫外和荧光光谱对产物进行表征,用循环伏安法考察其电化学行为,研究pH、氧对其荧光强度的影响。结果表明Ru(Hpip)3Cl2在玻碳电极上有准可逆的电化学行为,在溶液中其对氧的响应倍数(I0/I)高达11.9。 相似文献
998.
综述了合成茴香醛的研究进展情况,介绍了新技术在合成中的应用和发展趋势,着重对间接电氧化法氧化茴香脑制备茴香醛进行了评述。 相似文献
999.
有机添加剂对铝管表面硅烷涂层耐蚀性的影响 总被引:2,自引:0,他引:2
讨论了乌洛托品、植酸和吐温-80等3种有机添加剂在缓蚀液中对铝管表面硅烷涂层耐蚀性的影响.通过失重、析氢、盐雾试验和电化学阻抗(EIS)检测了铝管的耐蚀性.结果发现,有机添加剂的加入,使铝管的耐腐蚀性能大幅度提高,尤以乌洛托品为佳.在以乌洛托品为添加剂的缓蚀液里,铝管表面复合膜层均匀致密,中性盐雾试验达到420 h.初步探讨了缓蚀膜的成膜机理. 相似文献
1000.