Ana M. Criado

Introduction to Semiconductor Physics in Secondary Education: Evaluation of a teaching sequence

The present article presents a didactic proposal oriented to teaching notions of semiconductor physics in secondary education. The methods and the results of a pilot study designed to analyse the effectiveness of a teaching sequence on the topic are also described. The subjects were 60 students, aged 14–15 years, of a secondary school in Seville, Spain. The levels of knowledge acquired by the students were evaluated by means of a test and personal interviews, which we also used to detect the most frequent obstacles they encountered against learning. Also, we employed personal interviews and analysis of the students’ notebooks to evaluate their attitudes towards semiconductor physics and its learning, and to evaluate the degree to which the teaching sequence fosters cooperative learning and the self‐regulation of learning. The results indicated that the students in general acquired ideas and reasoning in the appropriate line, although with some mistakes or inaccuracies with respect to scientific conceptions, and acquired positive attitudes towards the learning of semiconductor physics, with a high degree of motivation during the teaching–learning process. The conclusion is that it is possible to initiate teaching the basic notions of semiconductor physics in secondary education, although it is necessary to continue going deeper into the topic with new research. As a proposal for improvement in future actions, we formulate new objectives oriented at overcoming the students’ commonest obstacles against learning with respect to the topic.

Chemistry of dithiocarbamate derivatives of amino acids. Part III. X-ray photoelectron spectroscopy of Ba(S2CNHCH2CO2)·3H2O. I.r. and e.s.r. studies of α-amino acid-dithiocarbamate complexes of copper(II)

SummaryCoordination compounds [Cu(S2CNHCHRCO2H)2], were obtained by reaction of dithiocarbamate derivatives of amino acids with copper(II), and the products were characterized by i.r. and e.s.r. spectroscopy. The xps spectrum of Ba(S2CNHCH2CO2)·3H2O is reported.

An Analysis of the Questions Proposed by Elementary Pre-Service Teachers When Designing Experimental Activities as Inquiry.

ABSTRACT A qualitative study of an interpretative nature is presented of the topics that elementary pre-service teachers (EPTs) choose and the types of questions they propose when designing an experimental activity (ExA) as inquiry, after receiving explicit instruction about it. The participants in the study were 154 EPTs organised into small groups to design an ExA. The data were processed using a rubric designed and applied through processes of inter- and intra-rater analysis. The results showed the instruction they had received to be, in general, effective for their formulation of quality questions that can generate ExA-based inquiry. Questions dealing with relations between variables were the commonest. In their free selection of the topic, the EPTs were most likely to ask high-order questions (i.e. ones that foster inquiry) on a wide variety of physics content. There were very few questions concerning biology, and none on chemistry, the environment, health sciences, and so on. After a discussion of the results, specific actions are proposed to improve future EPT training in the formulation of questions with which to initiate school science inquiry.

Prospective Teachers’ Difficulties in Interpreting Elementary Phenomena of Electrostatic Interactions: Indicators of the status of their intuitive ideas

Student teachers were tested before and after a teaching unit on electrostatic interactions in an attempt to consider their intuitive ideas and concept development. A study was made of students’ explanations of basic interactions: those between two charged bodies, and those between a charged body and a neutral body. Two indicators of the cognitive status of the explanations were investigated: “context dependence” and “certainty or confidence index”. This allowed cognitive comparisons to be established between the explanations of different electrostatic interactions, and between the degrees of difficulty they represent for satisfactory conceptual evolution. The greatest difficulties were found with explanations of the phenomena of electrostatic induction. The sample consisted of 52 students in primary school teacher education who participated in a teaching unit designed to overcome these obstacles.

Oxidation of bis(4-toluenesulphonyl-L-serinato)copper(II) to bis(formylglycine)copper(II)

SummaryOxidation of L-serine occurs on degradation of bis(L-serinato)copper(II) and at the same time copper is reduced.