Two new semiquantitative green chemistry metrics, the green circle and the green matrix, have been developed for quick assessment of the greenness of a chemical reaction or process, even without performing the experiment from a protocol if enough detail is provided in it. The evaluation is based on the 12 principles of green chemistry. The…

A laboratory inquiry into the thermochemical relationships in the reaction between aqueous solutions of NaHCO[subscript 3] and NaOH is described. The enthalpy change for this reaction, delta[subscript r]H, and that for neutralization of strong acid and NaOH(aq), delta[subscript n]H, are determined calorimetrically; the explanation for the…

This paper explores the research perspective of neuroscience by documenting the brain cell (neuron) drawings of undergraduates, trainee scientists, and leading neuroscience researchers in a single research-intensive university. Qualitative analysis, drawing-sorting exercises, and hierarchical cluster analysis are used to answer two related…

"PlantingScience" is an award-winning program recognized for its innovation and use of computer-supported scientist mentoring. Science learners work on inquiry-based experiments in their classrooms and communicate asynchronously with practicing plant scientist-mentors about the projects. The purpose of this study was to identify specific…

Teachers' professional knowledge is assumed to be a key variable for effective teaching. As teacher education has the goal to enhance professional knowledge of current and future teachers, this knowledge should be described and assessed. Nevertheless, only a limited number of studies quantitatively measures physics teachers' professional…

In this new context concept approach, field research on the Trinidadian guppy is used as an appealing example of evolutionary change in populations. Pupils are asked to investigate the underlying mechanisms. In doing so, defects in their knowledge are revealed, in particular the role of meiosis in creating genetic variation. The reason for these…

The aim of this study is to evaluate the effects of Argumentation Based Science Teaching on 5th grade students' conceptual understanding of the subjects related to "Matter and Change". This research is a qualitative research and its design is a multiple (compare) case study. In this study, semi-structured interviews related to the…

This qualitative study investigates the gap between a lab experiment and theory of science. Two groups of 4 students in 2 different classes in 11th grade (15-16 years old) are followed as they process results and experiences from a lab experiment using a digital environment. The experiment is as a part of a larger project about genes and cells,…

Designing opportunities for students to discover core science concepts can be challenging, however, with a good understanding of their interests, proper planning, and the use of technology and the outdoors, students can become engaged in a way that can leave a legacy for future students. Last fall, this author designed a nine-session unit for a…

Terms to be familiar with before you start to solve the test: tryptophan, transcription unit, operon, "trp" repressor, corepressor, operator, promoter, palindrome, initiation, elongation, and termination of transcription, open reading frame, coupled transcription/translation, chromosome-polysome complex. (Contains 2 figures and 1 footnote.)

Jay Orear, in his introductory physics text, defined the weight of a person as the reading one gets when standing on a (properly calibrated) bathroom scale. Here we will use Jay's definition of weight in a thought experiment to measure the weight of a photon. The thought experiment uses the results of the Pound-Rebka-Snider experiments, Compton…

The purpose of this laboratory experiment is to introduce aspects of materials chemistry, such as polymers and nanoparticle synthesis and properties, to students by their fabrication of a take-home polydimethylsiloxane window cling containing gold or silver nanoparticles. This lab covers small portions of three successive laboratory periods and is…

A multistep experiment for an advanced synthesis lab course that incorporates topics in organic-inorganic synthesis and catalysis and highlights green chemistry principles was developed. Students synthesized two "N"-heterocyclic carbene ligands, used them to prepare two well-defined copper(I) complexes and subsequently utilized the complexes as…

Winds in desert regions form the well-known barchan dunes. Frequently, human settlements are threatened by the migration of these dunes. But why do these dunes move? And how is dune migration in deserts connected to scour development in the vicinity of pylons in river beds or to snow cornices in alpine regions? This paper introduces the topic of…

During the Thai high-school physics teacher training programme, we used an aluminum loop-the-loop system built by the Institute for the Promotion of Teaching Science and Technology (IPST) to demonstrate a circular motion and investigate the concept of the conservation of mechanical energy. There were 27 high-school teachers from three provinces,…