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71.
学生对示意图提示条件普遍持肯定态度;学校教学水平影响学生非视觉化题目上的态度反应,而不影响视觉化题目上的态度反应.从整体上看,示意图提示条件能显著地促进学生的解题,但是这种促进作用受题目视觉化程度、学校教学水平的制约.在一定范围里,随着非视觉化题目难度增加示意图提示条件的作用在增强.  相似文献   
72.
The purpose of this study was to review and analyze effective classroom reading practices for early graders, using information gathered from the existing content-general and content-specific observation protocols measuring teachers’ classroom reading practices. Dimensions and constructs from 28 observation studies were synthesized to identify classroom instructional practices that have positive impacts on student achievement. Findings revealed that (a) instructional support, emotional support, and classroom management have positive impacts on student achievement, (b) the degree to which instructional practices are effective depends on students’ particular learning needs, and (c) students’ entering skills and primary language are associated with instructional effectiveness in reading. Challenges and implications for future research on effective instructional strategies for special education and the development of an observational protocol for special education teacher effectiveness are discussed.  相似文献   
73.
ABSTRACT

Mindfulness offers a pathway for preservice teachers to develop self-awareness, which is an essential part of personal and professional growth. However, supporting teacher self-awareness is rarely given much attention in teacher education programs. The authors studied the use of mindfulness meditation in an early childhood college course with early childhood preservice teachers. This article reports the main findings that emerged from the students’ journals regarding the mindfulness meditation. Reflecting on the findings, this article suggests that educators need to provide meaningful learning experiences and activities, which could help their students develop the personal qualities necessary to teach with high self-confidence.  相似文献   
74.
The inhibitory effects of Lactobacillus plantarum-fermented and non-fermented Inula britannica extracts on the tyrosinase activity were comparatively investigated to examine whether and how they improve the whitening activity, and the contents of total flavonoids and polyphenolics as bioactive compounds were determined. The skin whitening activity using in vitro or ex vivo tyrosinase and L-3,4-dihydroxyphenylalanine (L-DOPA) staining was examined. The total flavonoid content (TFC) was increased by 13.4% after 72 h-fermentation. The viabilities of the B16F10 cells treated with the fermented and non-fermented control extracts were 100.26% and 92.15% at 500 μg/ml, respectively. In addition, the inhibition of tyrosinase activity was increased by the fermented samples from 29.33% to 41.74% following fermentation for up to 72 h. The tyrosinase activity of the untreated control group was increased to 145.69% in B16F10 cells. The results showed that I. britannica fermented by L. plantarum dose-dependently inhibited tyrosinase activity, which was stimulated by α-melanocyte stimulating hormone. These results suggest that lactic fermented I. britannica extracts can be used as effective skin-whitening materials.  相似文献   
75.
In this study, we used a simple impregnation method to prepare Fe–Ce–O x catalysts and tested them regarding their low-temperature (200–300 °C) selective catalytic reduction (SCR) of NO using NH3. We investigated the effects of Fe/Ce molar ratio, the gas hourly space velocity (GHSV), the stability and SO2/H2O resistance of the catalysts. The results showed that the FeCe(1:6)O x (Ce/Fe molar ratio is 1:6) catalyst, which has some ordered parallel channels, exhibited good SCR performance. The FeCe(1:6)O x catalyst had the highest NO conversion with an activity of 94–99% at temperatures between 200 and 300 °C at a space velocity of 28,800 h?1. The NO conversion for the FeCe(1:6)O x catalyst also reached 80–98% between 200 and 300 °C at a space velocity of 204,000 h?1. In addition, the FeCe(1:6)O x catalyst demonstrated good stability in a 10-h SCR reaction at 200–300 °C. Even in the presence of SO2 and H2O, the FeCe(1:6)O x catalyst exhibited good SCR performance.  相似文献   
76.
程度副词修饰名词结构探析   总被引:2,自引:0,他引:2  
程度副词修饰名词原本不是一个被语法学界完全认可的语法组合,然而在当代口语及书面语中,“程度副词 名词”组合却有越来越多的人使用。可见,“程度副词 名词”虽是一类很特殊的结构,但已具有相当程度的可接受性。与一般意义上的名词不同,进入这一结构中的名词需具有由具体指称向情状描述转化的潜在语义特征,这一类名词与程度副词的组合弥补了形容词语义表达上的问题,并由此引发了部分名词向名形兼类词的转变。  相似文献   
77.
Due in large part to the trends towards economic globalization, English has become the most widely disseminated and ubiquitous international language. The purpose of the study was to investigate what Taiwan’s EFL teachers at the elementary level believe about the policy of English as a compulsory subject and how they perceive the benefits and obstacles of the policy’s implementation. Ten elementary English teachers in Tainan City and its suburban areas participated in this study. Data were collected through teachers’ interviews, classroom observation and document analysis. Results found that all ten teachers agreed with the policy for English as a compulsory subject at the elementary level. They observed both positive and negative sides of this top‐down policy. Classroom observation and interview data revealed that EFL teachers had to plan their English classes with the constraints on a large class of students with mixed levels of proficiency, limited teaching hours and resources. Parents’ expectations of and attitudes towards English learning also became an obstacle.  相似文献   
78.
有机化合物的水解反应及研究进展   总被引:4,自引:0,他引:4  
该文对有机化合物的水解反应机理、应用及研究进展进行综述。  相似文献   
79.
With the flooding of pornographic information on the Internet, how to keep people away from that offensive information is becoming one of the most important research areas in network information security. Some applications which can block or filter such information are used. Approaches in those systems can be roughly classified into two kinds:metadata based and content based. With the development of distributed technologies, content based filtering technologies will play a more and more important role in filtering systems. Keyword matching is a content based method used widely in harmful text filtering. Experiments to evaluate the recall and precision of the method showed that the precision of the method is not satisfactory, though the recall of the method is rather high. According to the results, a new pornographic text filtering model based on reconfirming is put forward. Experiments showed that the model is practical, has less loss of recall than the single keyword matching method, and has higher precision.  相似文献   
80.
现代教育技术对体育教育的影响   总被引:1,自引:0,他引:1  
运用多媒体计算机技术,针对普通高校传统体育教学模式的缺陷,论述了多媒体技术在普通高校体育教学中的应用,对改革现有的教学方法,提高教学效果,促进教学改革的深化作了初步的探讨。  相似文献   
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