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1.
含钒固废因其种类多、含有价元素、物相组成复杂,而成为资源回收和环境治理的重要研究对象。针对含钒固废亟待处理的问题,分析了我国含钒固废的种类、来源和资源特点,归纳了含钒固废的综合利用方式方法,包括提取有价元素、多组元综合利用及整体增值利用,总结了含钒固废在结构材料、钢铁冶金、功能材料、生态环保中的利用现状及发展,并指出了含钒固废在综合利用上存在的不足,提出含钒固废资源化利用的发展趋势,如制备地质聚合物、耐火材料、橡塑填料等实现零排放及整体增值的利用领域。 相似文献
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《Displays》2021
The air conditioning method based on radiation heat exchange has the characteristics of small vertical temperature gradient, high thermal comfort and energy saving, and has become a hot spot of attention. The Fluent numerical simulation, the experiment in this paper studies the direct expansion multi-line radiant air conditioner under the artificially simulated climate environment in winter heating, summer cooling and dehumidification. The temperature difference of the radiation + fresh air mode at the same time indoors under heating conditions is less than 2.5 °C, and the time to reach the indoor set temperature of 24 °C is about 2–3 h. Under cooling conditions, the temperature difference of the radiation + fresh air mode at the same time in the room is about 0.5–2 °C, and the time to reach the indoor set temperature of 26 °C is about 1–3 h. In the fresh air mode, the indoor temperature difference and response time at the same time are slightly larger than the radiation + fresh air mode. The freezing and dehumidification effect of fresh air is obvious, the moisture content of dehumidifying fresh air is between 6.3 and 10.5 g/kg, and the dehumidification efficiency can reach 50%. Under the same artificial simulated climate environment, the consumption of the three modes is not much different. When the outdoor temperature in heating conditions is higher than 9 °C, the fresh air mode can get better, and the radiation + fresh air mode can achieve better comfort when running indoors under various conditions. 相似文献
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Clean Technologies and Environmental Policy - Green technology innovation is imperative to sustainable and environmentally sound economic development and is currently facing increasingly serious... 相似文献
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对煤的自燃倾向进行快速有效鉴别,有助于对煤的自燃倾向采取分级分类管理从而有效防治煤矿火灾,因而采用绝热式自燃测试方法对煤的自燃倾向进行准确分析很有必要。简要介绍绝热式自燃测试方法的测试原理及其仪器结构,模拟煤炭自燃的物理过程,通过采用包括反应器、气体预热铜管和跟踪温度控制方式等综合绝热措施以实现300 g煤样的自然发火实验,记录煤样从40℃上升到70℃的升温速率(或前30 h的升温速率),测试煤样的自燃特性曲线并分析曲线特征。即建立煤绝热氧化产热速率计算模型,结合实验数据计算所得的煤在绝热氧化条件下的升温速率和产热速率可鉴定煤自燃倾向性的强弱。采用绝热式自燃测试方法对不同煤的自燃倾向分析后表明,无烟煤和部分烟煤的自燃倾向较低,褐煤的自燃倾向较高,故而在煤矿开采时需特别注意褐煤的自燃倾向。 相似文献
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《Journal of the European Ceramic Society》2020,40(5):1869-1876
In Part A of this study, infiltrations experiments of porous SiC samples by hexadecane with pore-size distributions comprising small and large pores were realized. Two successive stages were identified during the filling of these samples corresponding to the infiltration of the two types of pores. The experimental data were successfully treated with a new analytical function. In Part B, it was found that this function can also be applied to the analysis of the mass gain during molten silicon infiltration at 1500 °C. Prior to silicon infiltration, it was found that the operating temperature induces a shift of the pore size distributions towards larger values. A dissolution-recrystallisation mechanism can also occur during the infiltration of silicon. During the first stage, liquid silicon fills rapidly larger pores than hexadecane. The kinetics are significantly larger with liquid silicon. Consequently, the durations for the complete filling are very short with molten silicon. 相似文献
7.
《International Journal of Hydrogen Energy》2022,47(12):7836-7845
Catalyst samples for CH4 decomposition were prepared from red mud (RM) by an acid-leaching neutralization precipitation approach. Water-washing the resultant precipitates multiple times, followed by drying at 105 °C and calcination at 500 °C, resulted in a threshold of residual Na2O, equivalent to 96% Na2O removal. Drying the precipitate at a higher temperature of 200 °C, followed by repeated water washing, provided a deeper Na2O removal of 99% and made the resultant samples more active for the targeted reaction. Subsequently, four catalyst samples with a simulated red mud composition and NaOH contents from 0 to 0.3 wt% were prepared and the catalytic test results revealed that the Na2O remaining in the RM-derived catalysts did not only inhibit their activation in CH4 but also lower their maximal activities for CH4 decomposition. Finally, two catalysts with the same simulated red mud composition and their Na impregnated respectively on Fe2O3 and a mixture support of Al2O3-SiO2-TiO2 were prepared and tested to explore the effect of Na distribution on the activation behavior of RM-derived catalysts for CH4 decomposition. The activity testing results showed that it was the Na residual dispersed on iron oxides in the RM-derived samples to significantly inhibit the activation of CH4 decomposition. 相似文献
8.
为测试倾斜摄影测量技术路线,并通过实际项目的应用,解决传统古建筑建模过程中存在的时间成本高、难以还原复杂场景等问题。按照倾斜摄影技术的技术路线,进行朱氏宗祠建筑测绘试验,并通过基于altizure软件建立三维模型来展现倾斜摄影测量技术流程。验证无人机倾斜摄影应用于古建筑三维建模的可行性和可操作性。 相似文献
9.
Shuai Hu Chunhui Wang Ling Zhou Xifeng Zeng Li Shao Jun Zhou Chunxian Zhou Chenghuan Huang Xiaoming Xi Lishan Yang 《Ceramics International》2018,44(13):14995-15000
LiCoO2 nano-particles precursor was synthesized through a mixed-alkalis (LiOH-NaOH) hydrothermal reaction, and finally sintered into LiCoO2 nanobricks with a sickness of ~300?nm. This LiCoO2 nanobrick cathode delivered a specific capacity of 131.8 mAh g?1 at 1?C between 3.0 and 4.2?V and 90% capacity retention after 100 cycles. Those synthesized LiCoO2 nanobricks were further treated by surface Al3+ doping to achieve much enhanced 4.5?V lithium storage capability and cycling stability. EIS results showed the surface Al3+ doping operation can signification decrease the charge-transfer resistances of the LiCoO2 cathodes for both before and after cyclings. 相似文献
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