Co-benefit of hazardous trace elements capture in dust removal devices of ultra-low emission coal-fired power plants

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.     

Teaching Kids to Care about Jewish Problems: A Noddings’ Approach

Drawing on Noddings’ work on religion and education (1993), moral education (2002), and citizenship education (2005\, 2015), this article contemplates how educators both in public schools and parochial Jewish schools might teach students to care about critical issues confronting the Jewish community historically and contemporarily. Its premise is that the teaching of the Jewish experience is presently deficient in both school settings. The article suggests ways that Noddings’ conceptions of caring (1992), pedagogical neutrality (1993), and critical lessons (2006) can be adapted and applied to the teaching of Jewish civilization in more appropriate, holistic, and nuanced ways. Its implications are applicable to many other American subgroups whose treatment in the social studies curriculum is typically inadequate.     

Device Comparability of Tablets and Computers for Assessment Purposes

The definition of what it means to take a test online continues to evolve with the inclusion of a broader range of item types and a wide array of devices used by students to access test content. To assure the validity and reliability of test scores for all students, device comparability research should be conducted to evaluate the impact of testing device on student test performance. The current study looked at the comparability of test scores across tablets and computers for high school students in three commonly assessed content areas and for a variety of different item types. Results indicate no statistically significant differences across device type for any content area or item type. Student survey results suggest that students may have a preference for taking tests on devices with which they have more experience, but that even limited exposure to tablets in this study increased positive responses for testing on tablets.     

Elementary Teachers’ Perception of Language Issues in Science Classrooms

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.     

Children's agency beliefs, cognitive performance, and conceptions of effort and ability: individual and developmental differences

In order to understand how children's beliefs and cognitive performance vary according to development in their conceptions of effort and ability, 120 fourth and sixth graders were given the following assessments: (a) a measure of agency beliefs, defined as the extent to which persons believe they have access to certain classes of potential means, including effort, ability, powerful others, and luck; (b) a battery of intelligence test scales, including figural patterns, letter series, arithmetic, and spelling; (c) an interview designed to assess developmental levels in conceptions of effort and ability. Correlations between intelligence scores and agency beliefs for effort decreased with increasing levels of reasoning about effort and ability, but correlations between intelligence scores and agency beliefs for ability increased with increasing levels of reasoning. No such trends were found in correlations between performance and agency beliefs for luck or for unknown causes. The results are discussed in terms of the interaction between individual differences and developmental change.     

Does prior mathematics knowledge really lead to variation in elementary statistics performance? Evidence from a developing country

A model incorporating prerequisite mathematics performance and other variables deemed to be associated with learning elementary statistics (ES) is developed. The relationship between ES performance and the explanatory variables is well represented by the logistics form. Aptitude, effort and motivation are the only significant explanatory variables of ES performance. Since prerequisite mathematics is not significant, statistical thinking at the tertiary level may be mostly intuitive and non-mathematical. Students with low aptitude experience increasing returns to effort over the first half of the feasible effort interval, while high-aptitude students experience diminishing returns at all levels of effort. The levels of effort required to achieve a minimum pass are interpreted.     

Blurring the color line: The desegregation of the Baltimore city public schools, 1954–1994

Perched on the Mason-Dixon line, Baltimore ignored calls for resistance from its southern neighbors by becoming one of the first cities in the country to comply withBrown. By the beginning of the 1955 school year, leaders had implemented a desegregation plan, and Baltimore was being applauded for the early and peaceful integration of its public schools. Within a few years, however, the praise faded as it became clear that Baltimore still suffered from de facto segregation. Faced with this reality, the school board refused to take the steps necessary to remedy the problem, instead shifting the blame to society at large. This failure by the board started a pattern of abandonment by school leadership that culminated in 1991 with the privatization of several of Baltimore's public schools. The result of this abandonment is a crippled school system that still has not dealt with issues of race and equality.     

Goodness of fit in the home: its relationship to school behavior and achievement in children with learning disabilities

This study examined whether a "goodness of fit" theoretical model, applied to families with and without children with learning disabilities, would be valuable in understanding the children's performance in school. A home interview was conducted with 63 families with a child with learning disabilities and 53 families with a comparable child without learning disabilities. The mothers were asked to rate how their own child fit into the family's expectations for children. It was found that, for both groups of families, children who were rated as a "poor fit" in the home demonstrated less positive behavior in the classroom and poorer achievement over the elementary school years. There was some evidence that poor fit in the home was even more negatively related to outcomes for children with learning disabilities. Discussion is centered on the importance of this theoretical model for understanding the importance of the home on successful school function.     

Characteristics of an innovative learning environment according to students’ perceptions: actual versus preferred

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.