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介绍气化效率高、有利于环保、具有一定竞争力的Shell煤气化工艺原理、技术特点及关键设备。建议尽快实现关键技术和设备的国产化。 相似文献
104.
分析了景德镇民营陶瓷企业发展特点及其目前存在的问题,并就加快今后景德镇民营陶瓷企业发展步伐提出了几点建议。 相似文献
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106.
突扩突跌掺气设施后泄槽底板脉动压力试验研究 总被引:1,自引:0,他引:1
有压洞出口后的突扩突跌掺气减蚀设施在水利工程中经常使用。由于水流受边界条件和掺气的影响,其流态和脉动压力往往与普通水槽的情况有很大的不同。通过水工模型试验,对突扩突跌掺气设施后泄槽底板上的脉动压力进行研究,揭示了掺气设施后泄槽底板上不同流动区域的脉动压力特性。从脉动压力的时域过程、均方根值、偏态系数、峰态系数和主频率等多方面得出冲击区、反射区和稳定区脉动压力的特性是不相同的结论。同一流量时,沿流程底板的时均压力都大于脉动压力的均方根值,在冲击区、反射区和稳定区,脉动压力的均方根值分别是同位置时均压力值的约0.5倍、0.6倍和0.7倍。研究成果可为更好地利用突扩突跌掺气设施提供有益的理论和试验依据。 相似文献
107.
Gerontechnology acceptance by elderly Hong Kong Chinese: a senior technology acceptance model (STAM)
Ke Chen 《Ergonomics》2014,57(5):635-652
The purpose of this study was to develop and test a senior technology acceptance model (STAM) aimed at understanding the acceptance of gerontechnology by older Hong Kong Chinese people. The proposed STAM extended previous technology acceptance models and theories by adding age-related health and ability characteristics of older people. The proposed STAM was empirically tested using a cross-sectional questionnaire survey with a sample of 1012 seniors aged 55 and over in Hong Kong. The result showed that STAM was strongly supported and could explain 68% of the variance in the use of gerontechnology. For older Hong Kong Chinese, individual attributes, which include age, gender, education, gerontechnology self-efficacy and anxiety, and health and ability characteristics, as well as facilitating conditions explicitly and directly affected technology acceptance. These were better predictors of gerontechnology usage behaviour (UB) than the conventionally used attitudinal factors (usefulness and ease of use).
Practitioner Summary: Previous studies have not given much consideration to age-related health and associated abilities when examining acceptance of technology by the ageing population. By encompassing conventional technology acceptance constructs together with age-related health and ability characteristics, the present study was able to identify more factors affecting gerontechnology acceptance by older Hong Kong Chinese. 相似文献
108.
Faliang Zhang Yongchun Luo Anqiang Deng Zhaohui Tang Long Kang Jianhong Chen 《Electrochimica acta》2006,52(1):24-32
(La, Ce, Pr, Nd)2MgNi9 hydrogen storage alloys were prepared through induction melting followed by a long annealing treatment. The structure and electrochemical properties of annealed alloys have been investigated by orthogonal design experiments. Both the individual effects of each substituting element and their interaction in alloys were studied systemically. It has been shown that the structure of main phase in alloys belongs to PuNi3-type with a space group R-3m. Substituting rare-earth elements have a significant effect on both the phase structure of alloys and microstructure. The anisotropic change in the crystal structure of alloys can cause the acceleration of pulverization of alloy particles and result in the deterioration of the cyclic stability of alloy electrodes. Misch metals can raise the plateau pressure of hydrogen absorption/desorption. The discharge capacity of alloy ranges from 342.97 to 380.68 mAh g−1 depending on the sort and content of substituting elements. Both cerium and neodymium can obviously reduce the discharge capacity of alloy electrodes. When compared to the La2MgNi9 alloy electrode, mish metals can significantly improve the high rate dischargeability of alloy electrodes. The improvement of the kinetic characteristic of alloy electrodes mainly results from the increase of the hydrogen diffusion rate in alloy bulk. 相似文献
109.
本文研究了炭黑-环氧树脂复合材料的制备工艺及炭黑填充率对材料电阻率的影响。实验结果表明,加入表面活性剂,明显改善了炭黑在环氧树脂中分布的均匀性。炭黑-环氧树脂材料具有明显的渗流效应,正温度系数效应即PTC效应,非线性伏安特性和电磁波屏蔽效应。 相似文献
110.
T. Hoshikawa 《Electrochimica acta》2006,51(25):5286-5294
Effects of the electrolyte of DSCs on impedance spectra were evaluated by changing concentration of redox couple, viscosity, and additives to electrolyte. The relation with current-voltage characteristics (I-V characteristics) was investigated. In many cases, the impedance component attributed to charge transfer at TiO2|electrolyte interface demonstrated strong relation with the I-V characteristics. The recombination of electrons in TiO2 with I3− in electrolyte was a key factor in determining performance of DSCs. To evaluate the effect of I3−, diffusion-limiting current in the electrolyte for various viscosities was evaluated by cyclic voltammetry. When the short circuit current (SCC) was almost equal to the diffusion-limiting current, strong influence of the diffusion coefficient on the impedance spectra was observed: impedance arcs were enlarged as the diffusion coefficient was decreased. On the other hand, when the diffusion-limiting current was larger than the SCC, photo-excitation and electron injection processes became dominating factors in the DSCs performance. The SCC was regulated by the charge recombination process at TiO2|electrolyte interface, and thus the impedance component ω3 was related to the performance in such condition. 相似文献