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101.
The ozonation of aniline and anilinium ion in aqueous solution is investigated by determining the product distributions at different degrees of ozonation. Results indicate that anilinium ion, although less reactive than aniline, still has a remarkable reactivity towards ozone. The high anilinium ion reactivity and the observed product distributions are explained by assuming a radical mechanism for anilinium ion ozonation, whereas the behavior of aniline appears to be regulated mainly by the electrophilic ozonolysis mechanism.  相似文献   
102.
This paper addresses an integrated design of paraffin-reformer, gas separations and the electricity production with a solid oxide fuel cell (SOFC). The overall design consists of three modules. First module is a system of paraffin reformer. In this module, the paraffin feed stream is to send to a steam-reformer. In the second module, the gas separations method illustrated is the combination of a methane-permeable membrane with a pressure-swing adsorption (PSA). In the third module, the purified hydrogen is fed to the SOFC unit. To be energy efficient, this paraffin-fueled SOFC system is designed with the consideration of heat integration. The intent of this paper is to provide a possible, alternative way of cogeneration systems for refinery and petrochemical plants.  相似文献   
103.
Shu-Juan Zhang  Hui-Min Feng 《Carbon》2006,44(10):2059-2068
A novel method was developed for the fabrication of activated carbon fiber (ACF) with wet spinning polyvinyl alcohol (PVA) fibers as the precursors. Through a combination of preoxidation, dehydration, carbonization and activation under a certain tension, PVA-based ACFs (PVA-ACFs) with high yields and good mechanical properties were obtained. The surface and cross-section morphologies, pore structures, surface geometries, surface functional groups and crystal structures of the PVA-ACFs were characterized using field emission scanning electron microscopy, low temperature nitrogen adsorption, Fourier transformed infrared spectrophotometry, X-ray photoelectron spectroscopy and X-ray power diffraction. All the PVA-ACF samples prepared had lotus root-like axially meso- and macroporous structures with the domination of micropores. Fractal geometries of PVA-ACFs deduced from nitrogen adsorption isotherms indicates that capillary force dominated in the interactions between nitrogen and the PVA-ACFs. The surface functional groups of the PVA-ACFs depend on the activating agents. Graphitoidal crystal structures were observed for the PVA-ACFs. The small crystal size and short range ordering between the crystallites ensured a high specific surface area of the PVA-ACFs.  相似文献   
104.
水辅助注塑大直径介质导管制品的冷却分析   总被引:2,自引:0,他引:2  
王大中  郑一泉  黄锐 《塑料工业》2003,31(6):21-24,8
采用数学分析方法,通过假设、简化分析模型,用数学模型来表述物理模型,确定了水辅助注塑(VAIM)大直径介质导臂制品的冷却时间,并运用算例和国外试验的结果进行验证。结果发现:水辅助注射成型新工艺可以更加显著地缩短注塑周期,降低制件壁厚,允许制件有更大的实际直径。因此,VAIM技术可用来高效率地生产大直径、高质量、薄壁的介质导臂。  相似文献   
105.
闫玲  张吉晨  汪洪杰 《化工机械》2003,30(3):166-168,172
以单内管套管式换热器为例 ,分析了管道化溶出系统大型套管式换热器热补偿的设计方法 ,重点分析了内外管膨胀差的补偿及其弯管部分的结构设计。另外 ,对一些与热补偿相关的结构 ,如封闭环的设置也进行了必要的分析  相似文献   
106.
Firemen often suffer from heat strain. This study investigated two chest cooling systems for use under a firefighting suit. In nine male subjects, a vest with water soaked cooling pads and a vest with water perfused tubes were compared to a control condition. Subjects performed 30 min walking and 10 min recovery in hot conditions, while physiological and perceptual parameters were measured. No differences were observed in heart rate and rectal temperature, but scapular skin temperature and fluid loss were lower using the perfused vest. Thermal sensation was cooler for the perfused vest than for the other conditions, while the cool pad vest felt initially cooler than control. However, comfort and RPE scores were similar. We conclude that the cooling effect of both tested systems, mainly providing a (temporally) cooler thermal sensation, was limited and did not meet the expectations.  相似文献   
107.
This study examined the effect of active pre-warming on speed and quality of performance during simulated firefighting exercise. Twelve male firefighters performed two trials in counterbalanced order. They were either pre-warmed by 20-min cycling at 1.5 Watt kg1 body mass (WARM) or remained thermoneutral (CON) prior to a simulated firefighting activity. After the pre-warming, gastrointestinal temperature (P < 0.001), skin temperature (P = 0.002), and heart rate (P < 0.001) were higher in WARM than in CON. During the firefighting activity, rating of perceived exertion, thermal sensation and discomfort were higher for WARM than for CON. Finish time of the firefighting activity was similar, but the last task of the activity was completed slower in WARM than in CON (P = 0.04). In WARM, self-reported performance quality was lower than in CON (P = 0.04). It is concluded that pre-warming reduces the speed during the last part of simulated firefighting activity and reduces self-reported quality of performance.  相似文献   
108.
对水平钢化炉内传动辊的温度场进行了数值模拟。在研究玻璃加热过程时,传动辊释放出的辐射热是个非常重要的因素,其大小与传动辊的温度有关,影响着钢化玻璃的质量。传动辊温度随加热时间而改变,在计算玻璃板温度时,必须与传动辊的温度场耦合求解。  相似文献   
109.
S.P AppleyardB Rand 《Carbon》2002,40(6):817-834
This paper reports the systematic characterisation of changes in the structure and properties of a series of unidirectional carbon-carbon composites at key stages of processing. The composites were fabricated from PAN-based carbon fibres (surface treated and untreated) and two carbon matrix systems (graphitising and non-graphitising). The effects of matrix shrinkage, together with thermal expansion mismatch and interfacial bonding, established the composite structure and hence the composite properties. The morphology and interconnectivity of the shrinkage cracks, the strength and nature of the fibre-matrix interfacial interaction and the development of matrix texture were identified as key structural features. These features were characterised and their effect on subsequent processing stages (densification) and composite properties was determined.  相似文献   
110.
The purpose of the ozone process at the Sebago Lake Water Treatment Facility (SLWTF) is to meet the disinfection requirements of the Surface Water Treatment Rule with ozone and without filtration. The start-up experience is presented including initial operating strategies to meet disinfection requirements. An ozone system performance test conducted during the first month of plant operation is described and the results are reviewed. The initial and proposed activities of an ozone optimization project are discussed.  相似文献   
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