To broaden the application of SiO_(2) sol-bonded castables,using micro-or nano-Al_(2)O_(3) powder and SiO_(2) gel powder as the main raw materials,the effects of CaO impurity on the formation of mullite by the reactio...To broaden the application of SiO_(2) sol-bonded castables,using micro-or nano-Al_(2)O_(3) powder and SiO_(2) gel powder as the main raw materials,the effects of CaO impurity on the formation of mullite by the reaction of Al_(2)O_(3) and SiO_(2) at different temperatures(1350,1400,1500,and 1600℃)in different atmospheres(oxidation atmosphere and reduction atmosphere)were studied.The results show that in the oxidizing atmosphere,the introduction of CaO can promote the formation of mullite.When the temperature increases from 1350℃to 1600℃,the amount of mullite formed gradually increases.In the reducing atmosphere,the introduction of CaO is not conducive to the formation of mullite,and the amount of mullite decreases with the increasing temperature.The smaller the particle size of Al_(2)O_(3),the more easily it reacts with SiO_(2) gel powder to form mullite.展开更多
[Objectives]To facilitate the rational use and timely protection of the Tibetan medicinal plant resources to count and reorganize Tibetan medicines recorded in Yu Tuo Ben Cao.[Methods]Based on literature research and ...[Objectives]To facilitate the rational use and timely protection of the Tibetan medicinal plant resources to count and reorganize Tibetan medicines recorded in Yu Tuo Ben Cao.[Methods]Based on literature research and data analysis,this paper analyzed the plant genera,and their habitat characteristics and the main types of diseases.[Results]Yu Tuo Ben Cao contains 191 kinds of botanicals,of which Ranunculaceae has the largest number of 11 genera and 25 species,with a wide distribution of habitats and 5 categories,and the main therapeutic efficacy covers 16 fields.[Conclusions]As a part of Yu Tuo Ben Cao,Tibetan medicines of Ranunculaceae have great research value because of their variety,large number,wide distribution,and diverse uses.展开更多
热化学储能(thermochemical energy storage,TCES)技术是未来可再生能源社会最具前景的技术之一。Ca(OH)_(2)/CaO TCES体系因其储能密度较高、环境友好、廉价等特点受到人们的广泛关注。本工作建立了一个直接与间接混合加热的固定床反...热化学储能(thermochemical energy storage,TCES)技术是未来可再生能源社会最具前景的技术之一。Ca(OH)_(2)/CaO TCES体系因其储能密度较高、环境友好、廉价等特点受到人们的广泛关注。本工作建立了一个直接与间接混合加热的固定床反应器实验平台,进行了空气氛围下的储/释热实验,探究了混合加热反应器内的储热特性与限制因素,并在此基础上探究了在反应器尺度改善循环性能的可行方案。实验研究表明,采用直接与间接混合加热的方式,使得反应呈现向心推进与逐层推进相结合的形式,增进了储能反应的速率;反应性能随着循环次数增多逐渐下降,5次循环后的储能反应最大转化率降低了5.6%,10次循环相较于5次循环的反应最大转化率降低了3.8%。TG实验与粒径测试结果表明,空气中CO_(2)是造成循环性能下降的主要因素;提高脱水温度可以有效恢复循环性能,650℃时所提供的过余温度可以有效降低反应物中CaCO_(3)的含量。展开更多
基金This work was financially supported by National Natural Science Foundation of China(Nos.52172031 and 51872266).
文摘To broaden the application of SiO_(2) sol-bonded castables,using micro-or nano-Al_(2)O_(3) powder and SiO_(2) gel powder as the main raw materials,the effects of CaO impurity on the formation of mullite by the reaction of Al_(2)O_(3) and SiO_(2) at different temperatures(1350,1400,1500,and 1600℃)in different atmospheres(oxidation atmosphere and reduction atmosphere)were studied.The results show that in the oxidizing atmosphere,the introduction of CaO can promote the formation of mullite.When the temperature increases from 1350℃to 1600℃,the amount of mullite formed gradually increases.In the reducing atmosphere,the introduction of CaO is not conducive to the formation of mullite,and the amount of mullite decreases with the increasing temperature.The smaller the particle size of Al_(2)O_(3),the more easily it reacts with SiO_(2) gel powder to form mullite.
基金Supported by Key Laboratory of Medicinal Animal and Plant Resources of Qinghai-Tibetan Plateau in Qinghai Province(2020-ZJ-Y40).
文摘[Objectives]To facilitate the rational use and timely protection of the Tibetan medicinal plant resources to count and reorganize Tibetan medicines recorded in Yu Tuo Ben Cao.[Methods]Based on literature research and data analysis,this paper analyzed the plant genera,and their habitat characteristics and the main types of diseases.[Results]Yu Tuo Ben Cao contains 191 kinds of botanicals,of which Ranunculaceae has the largest number of 11 genera and 25 species,with a wide distribution of habitats and 5 categories,and the main therapeutic efficacy covers 16 fields.[Conclusions]As a part of Yu Tuo Ben Cao,Tibetan medicines of Ranunculaceae have great research value because of their variety,large number,wide distribution,and diverse uses.
文摘热化学储能(thermochemical energy storage,TCES)技术是未来可再生能源社会最具前景的技术之一。Ca(OH)_(2)/CaO TCES体系因其储能密度较高、环境友好、廉价等特点受到人们的广泛关注。本工作建立了一个直接与间接混合加热的固定床反应器实验平台,进行了空气氛围下的储/释热实验,探究了混合加热反应器内的储热特性与限制因素,并在此基础上探究了在反应器尺度改善循环性能的可行方案。实验研究表明,采用直接与间接混合加热的方式,使得反应呈现向心推进与逐层推进相结合的形式,增进了储能反应的速率;反应性能随着循环次数增多逐渐下降,5次循环后的储能反应最大转化率降低了5.6%,10次循环相较于5次循环的反应最大转化率降低了3.8%。TG实验与粒径测试结果表明,空气中CO_(2)是造成循环性能下降的主要因素;提高脱水温度可以有效恢复循环性能,650℃时所提供的过余温度可以有效降低反应物中CaCO_(3)的含量。
