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211.
Juliana Utley Toni Ivey Rebekah Hammack Karen High 《School science and mathematics》2019,119(4):203-212
The Next Generation Science Standards emphasizes the inclusion of engineering practices throughout the K–12 science curriculum. Therefore, elementary educators need to be knowledgeable about engineering and engineering careers so that they can expose their students to engineering. The purpose of this study was to examine the effect of engineering professional development on in‐service elementary teachers’: (a) knowledge and perceptions regarding engineering, and (b) self‐efficacy of teaching engineering. This quantitative study revealed that even one professional development opportunity can help to alleviate some misconceptions about the work of engineers and what constitutes technology, as well as increase teachers’ confidence to teach engineering concepts. 相似文献
212.
In response to the call for more rigorously validated educational assessments, this study used an iterative multimethod validation process to develop and validate outcomes from the 21st Century Skills Assessment global rating scale. Qualitative and quantitative data sources were used to inform four types of validity evidence: content, response process, internal structure, and consequential. STEM experts and typical assessment users provided support for content, response process, and consequential validity evidence through focus group interviews and cognitive interviews. Psychometric findings suggest strong internal validity evidence for the assessment through high measures of internal consistency reliability, intra‐rater agreement, and test–retest reliability measures. 相似文献
213.
Toni Heikkinen 《Journal of Mathematical Analysis and Applications》2010,368(2):508-524
We study the extension properties of Orlicz-Sobolev functions both in Euclidean spaces and in metric measure spaces equipped with a doubling measure. We show that a set E⊂R satisfying a measure density condition admits a bounded linear extension operator from the trace space W1,Ψ(Rn)E| to W1,Ψ(Rn). Then we show that a domain, in which the Sobolev embedding theorem or a Poincaré-type inequality holds, satisfies the measure density condition. It follows that the existence of a bounded, possibly non-linear extension operator or even the surjectivity of the trace operator implies the measure density condition and hence the existence of a bounded linear extension operator. 相似文献
214.
Science as a Learner and as a Teacher: Measuring Science Self‐Efficacy of Elementary Preservice Teachers 下载免费PDF全文
Academic science achievement of U.S. students has raised concerns regarding our ability as a nation to compete in a global economy. Additionally, research has shown that many elementary teachers have weak science content backgrounds and had poor/negative experiences as students of science, resulting in a lack of confidence regarding teaching science. However, efforts to increase science self‐efficacy (SE) in preservice teachers can help to combat these issues. This study looked at a sample of preservice elementary teachers engaged in a semester‐long science content course, using Bandura's concept of SE as a conceptual framework. Our quantitative data showed significant increases in science SE on both subscales (personal efficacy and outcome expectancy). Our qualitative data showed that students communicated an increased sense of confidence with regard to the discipline of science. In addition, students reported learning science pedagogy through the instructor's modeling. Combining our findings resulted in several meta‐inferences, one of which showed students growing as both confident learners of science and teachers of science simultaneously. We created a construct new to the literature to describe this phenomenon: “teacher‐learner,” for students are both learning science and learning to teach science simultaneously through the content course experience, resulting in increased science SE. 相似文献
215.