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For the first time, graphite fibers have been electrochemically intercalated with Br that have the same structure and properties as those intercalated from vapor phase Br2. This was accomplished by intercalating pitch-based Thornel® K-1100 graphite fibers at low temperature (near 0 °C) and high currents (2 A) for long times (6 h). The mechanism appears to be that Br is oxidized to aqueous Br2 which, when sufficient local concentration builds up, intercalates the fiber. This was confirmed by intercalating K-1100 fiber in a saturated aqueous Br2 solution without passing an electrical current. The applied voltage does apparently lower the activation energy of the reaction as evidenced by the observation that P-120 and P-100 fibers will not intercalate in aqueous Br2 unless a voltage is applied.  相似文献   
23.
Tzong-Horng Liou 《Carbon》2004,42(4):785-794
Both fine carbon/silica and pure silica powders can be obtained by carbonization and combustion of rice husk under non-isothermal conditions, and the products can be used for preparation of high-quality ceramic materials. Studies on the morphology, chemical and physical characteristics of products were carried out by N2-adsorptionmeter, SEM, XRD, FTIR, ICP-MS and EA. Results indicate that decreasing the heating rate increased the specific surface area, pore volume and pore diameter. At a heating rate of 5 °C/min, the specific surface areas of both the carbon/silica and pure silica powders were 261 and 235 m2/g, and the average pore diameters were 2.2 and 5.4 nm, respectively. The products obtained from various heating rates were all amorphous. Thermogravimetric analysis was employed to study the reaction characteristics during carbonization or combustion, indicating that decomposition process of rice husk could be divided into three temperature zones. This results of the study can also provide the important information on the recovery of biomass material from rice husk.  相似文献   
24.
该文介绍了基于B/S资料信息管理系统的设计和开发,重点阐述了资料信息管理系统的开发设计的难点和要点,同时提供了部分数据库表信息和代码。  相似文献   
25.
该文简单介绍了B/S网络应用开发架构,详细阐述了网页闹铃功能设计,并对原理进行了详细的讲解,对功能做了进一步的实现,展示了运行效果。  相似文献   
26.
As the use of smartphones become popular,people heavily depend on smartphone applications to deal with their social activities.For this reason,traditional message texting between mobile applications does not fulfill the versatile requirements of social networking.Many mobile applications use multimodality to deliver multimedia messages including sticker,voice and photo message,video call,and snap movie to enhance the communicative capability.However,without face-to-face interaction,people may fail to detect the other side’s non-verbal social behavior such as fine-grain facial expressions,body movements,or hand gesture.During social interaction,non-verbal behavior conveys information about the involved individuals and help the speakers express their social emotion in an implicit way.It is so important for real-world face-to-face interaction but is often blocked on the mobile telephony.To cope with this problem,we propose an afective computing model to assist the representation of social emotion and then help the progress of social interaction on the mobile telephony.In this model,for the purpose of real-time afective analysis,we delegate the computing loading to the cloud side service and enhance the system’s scalability and availability.The result of this experiment approves the feasibility of our system design for the applications of social intelligent.Also,the system provides a research framework of the social intelligent system on the mobile telephony.  相似文献   
27.
Caroline Cannizzo 《Polymer》2005,46(4):1269-1276
Translucent boronic acid-carrying nanolatexes are prepared by copolymerisation of vinylbenzyl chloride in microemulsion followed by post functionalisation with 3-aminophenylboronic acid. The diol binding capacity and selectivity of the phenylboronic acid remain unchanged after anchoring to polymer nanoparticles (16 nm diameter, 0.22 mmol/g). The binding of a catechol dye, Alizarin Red S (ARS), to the boronic acid-carrying nanoparticles affords a colored, stable, nanolatex which is used for the selective visual detection of fructose in a competitive assay. The binding of fructose at pH 8.2 is readily evidenced by a color change and monitored by UV/Vis spectroscopy. The nanosensor can be regenerated in acidic medium. The entrapment of the nanolatex in a dialysis cell provides a re-usable support for binding and optical detection.  相似文献   
28.
为了能够准确地测量污水旋流池的液面高度,设计了基于超声传感技术的污水旋流池液面测量方法,通过长时间的运行,测量数据完全满足污水旋流池的生产工艺要求。  相似文献   
29.
The kinetics of intergranular oxidation of silicon in a 20Cr-25Ni Nb-stabilized stainless steel are reported, at temperatures in the range 1140–1230 K, in CO2 at 40 bar pressure. The depth of attack increased parabolically with respect to time, with an activation energy of 335±30 kJ/mol. The mechanism of growth is discussed in terms of classical internal-oxidation theories, and an alternative explanation based on an available-space theory is developed. The internal oxidation rates in a number of different alloys are compared with diffusivities of metals in the base alloy. It is proposed that intergranular oxidation in the 20–25 Nb steel is controlled by the rate of outward diffusion of iron or chromium in the alloy.  相似文献   
30.
通过鱼骨图的方法对现有智能公交投币机存在识别率偏低的问题进行了分析,提出在智能投币机中采用闭式五角叶轮或增加硬币预处理部分,对现有的智能公交投币机进行改进,使智能公交投币机的硬币辨识率得到提高.  相似文献   
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