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991.
Cheng-hang Zheng Li Wang Yong-xin Zhang Wei-guo Weng Hai-tao Zhao Jin-song Zhou Xiang Gao 《浙江大学学报(A卷英文版)》2018,19(1):68-79
The co-benefit of hazardous trace elements such as mercury (Hg), arsenic (As), and selenium (Se) capture in dust removal devices of ultra-low emission coal-fired power plants was investigated. Feed fuel and ash samples collected from 15 different coal-fired power units equipped with ultra-low emission systems were characterized to determine the concentrations and distribution characteristics of trace elements. It was found that the low-low temperature electrostatic precipitator (LLT-ESP) and the electrostatic fabric filter (EFF) had greater abatement capacity for Hg than normal cold-side ESP (CS-ESP). Only 0.8%–36.1% of Hg escaped from LLT-ESP and EFF, whereas 42.1%–90.6% of Hg escaped from CS-ESP. With the employment of EFF and ESP (inlet temperature<125 °C), 72.3%–99.1% of As and 70.7%–100% of Se could be captured before the wet flue gas desulfurization (WFGD) system. The significance level of the effects on the abatement capacity for Hg, As, and Se in ESP were analyzed by the Pearson correlation analysis and grey relational analysis. The results indicated that the low inlet temperature of LLT-ESP had significant promotional effect on the simultaneous removal of Hg, As, and Se. The smaller particle size of fly ash can be conducive to the adsorption of hazardous trace elements. The inhibitory effect of sulfur content in coal was significant for the enrichment of Hg and Se in fly ash. 相似文献
992.
“物质跨膜运输的方式”是人教版普通高中生物课程标准教科书《分子与细胞》模块第四章第三节的内容。物质跨膜运输的方式主要分为被动运输和主动运输。被动运输包括自由扩散和协助扩散,是顺浓度梯度运输的过程,不需要消耗能量,但协助扩散需要载体蛋白协助。主动运输是逆浓度梯 相似文献
993.
994.
煤矿60KY变电所6KV侧双回路供电系统中,为确保供电的可靠性,不允许两回路线路并列运行。若两回路并列运行,当线路中出现单相接地故障时会给选线工作造成困难,尤其发生两相或三相短路时对继电保护的影响更大,会造成越级跳闸事故,使变电所全面停电。 相似文献
995.
Lay Hoon Seah 《International Journal of Science and Mathematics Education》2016,14(6):1059-1078
Although the importance of language in science learning has been widely recognized by researchers, there is limited research on how science teachers perceive the roles that language plays in science classrooms. As part of an intervention design project that aimed to enhance teachers’ capacity to address the language demands of science, interview data (N = 9) were collected to understand teachers’ perceptions and experiences with a wide range of issues related to language use in science classrooms. Adopting an interpretive approach to qualitative data, the analysis revealed that the teachers perceive a wide range of student difficulties related to language use in science classrooms, especially to the use of specialized terms and writing. Although the teachers are keenly aware of how language can be a barrier to learning science, they are less certain as to what students need to know about the language of science in order to master it. The findings suggested professional support that highlights the distinctive language demands of science and how these demands differ from other subject areas could be useful to these elementary school teachers. 相似文献
996.
广告是一种特殊的交际行为,广告的翻译不能够等同于一般意义上的翻译.我们在研究广告翻译时,不能单纯用传统的翻译理论来对其进行指导.本文试图把现代广告的目的及其主要功能与Sperber和Wilson提出的关联理论相结合,通过实例分析,寻求广告翻译的最佳关联. 相似文献
997.
在"中国制造2025"背景下,一系列智能制造产业宏观政策出台,高职院校需要紧跟智能制造产业发展趋势,构建以智能工厂、工业机器人、精密测量和先进制造等智能环境为基础的人才培养平台,以满足新形势下政府、企业和学校对智能制造产业发展的需求。 相似文献
998.
人际关系学说及其对教育管理实践的影响 总被引:1,自引:0,他引:1
简要概述了人际关系学说的产生及其主要观点,探讨了该理论对教育管理实践的重要影响,并结合科学管理理论,对此做出了一定的分析。 相似文献
999.
Liu rong 《广西大学梧州分校学报》2007,(6)
在数字电路教学中,恰当地运用Multiim8仿真软件进行实时仿真,将理论与实验相结合,可以克服传统理论教学中的不足,提高数字电路课程的教学质量。 相似文献
1000.
An innovative learning environment is the current outcome of the constructivist approach, the essence of which is co-construction of knowledge in an Information and Communication Technology (ICT) environment. We examined how Israeli students perceived 10 characteristics of their classroom learning environment—student cohesiveness, teacher support, involvement, task orientation, investigation, cooperation, equity, differentiation, computer usage and young adult ethos. Particular foci were students’ perceptions of the actual state of their learning environment compared with the preferred state, and which characteristics predicted students’ cooperation. Participants were 1022 students in 33 classes from 12 computerised elementary and middle schools in Israel. Data were collected using the Technology-Rich Outcomes-Focused Learning Environment Inventory (TROFLEI). Results indicated a gap between the actual and the preferred states for all characteristics, although the scope of these gaps differed between elementary-schools students and middle-school students for certain characteristics. Structural equation modelling (SEM) analysis indicated that nine characteristics of the innovative environment in both actual and preferred states were related to cooperation, with these relations being primarily direct with the exception of teacher support and differentiation which had an indirect influence. Teacher support was mediated through student cohesiveness, involvement, equity and young adult ethos, whereas differentiation was mediated through investigation. Evaluation of the innovative learning environment might lead to better insights regarding the behaviours and needs of twenty-first century students in Israel’s education system. These insights could advance constructivist processes and teaching methods and bring the students to effective cooperative learning in an innovative learning environment. 相似文献