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[en] The claim has often been made that nanotechnologies will contribute to the global development process. In 2005, a careful study identified specific areas where nanotechnologies could help developing countries achieve the millennium development goals. This article examines whether the research agenda of nanotechnology in the intervening period, as reflected in publications, has followed the directions identified at that time, in three key areas, water, energy, and agri-food. We find that the research community has taken up the broad directions indicated in the earlier study, although not so often the detailed applications of specific nanoscale techniques or phenomena. However, the impact on global development is unclear, both because the same applications can be useful in both developed and developing countries, and because the conditions in developing countries may not match the socio-technical requirements of the applications
[en] Spatially and spectrally resolved low-energy cathodoluminescence (CL) microscopy was applied to the characterization of nanostructures. CL has the advantage of revealing not only the presence of luminescence centers but also their spatial distribution. The use of electrons as an excitation source allows a direct comparison with other electron-beam techniques. Thus, CL is a powerful method to correlate luminescence with the sample structure and to clarify the origin of the luminescence. However, caution is needed in the quantitative analysis of CL measurements. In this review, the advantages of cathodoluminescence for qualitative analysis and disadvantages for quantitative analysis are presented on the example of nanostructures. (topical review)
[en] This contribution is focused on fabrication processes of nanostructured material formed from organic self-assembly (nicotine amide supergelators), polymers (zwitterionic polymers and their copolymers), metal carbide (Mxene, WC) and alloy-based nanocomposite. Moreover, their application such as reusable fuel gels, controlled solution (upper critical solution temperature) and cell adhesion materials, biosensing, sustainable osmotic engine and in heterogenous catalytic processes such as direct methanol fuel cells and hydrogen evolution reaction will be presented and discussed. (authors)
[en] The insulator band gap Eg of graphene nanoribbons, one side of which is completely coated with hydrogen, is calculated numerically. It is shown that Eg is ∼1.5 eV narrower than the band gap in graphane nanoribbons with the same width w and steadily increases with decreasing w. As in graphane nanoribbons, the atomic structure of nanoribbon edges has virtually no effect on the value of Eg.
[en] The purpose of the study was to examine the effect of activity-based nanoscience and nanotechnology education (ABNNE) on pre-service science teachers’ (PST’) conceptual understanding of nanoscience and nanotechnology. Within this context, the study was conducted according to mixed methods research with the use of both quantitative and qualitative methods. The participants were 32 PST who were determined by using criterion sampling that is one of the purposive sampling methods. ABNNE was carried out during 7 weeks as 2 h per week in special issues at physics course. Design and implementation of ABNNE were based on “Big Ideas” which was found in literature and provided guidance for teaching nanoscience and nanotechnology. All activities implemented during ABNNE were selected from literature. “Nanoscience and Nanotechnology Concept Test (NN-CT)” and “Activity-Based Nanoscience and Nanotechnology Education Assessment Form (ABNNE-AF)” were used as data collection tools in research. Findings obtained with data collection tools were discussed with coverage of literature. The findings revealed that PST conceptual understanding developed following ABNNE. Various suggestions for increasing PST conceptual understanding of nanoscience and nanotechnology were presented according to the results of the study.