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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] Academic nanoscale science and engineering (NSE) research provides a foundation for nanotechnology innovation reflected in patents. About 60% or about 50,000 of the NSE-related patents identified by 'full-text' keyword searching between 1976 and 2004 at the United States Patent and Trademark Office (USPTO) have an average of approximately 18 academic citations. The most cited academic journals, individual researchers, and research articles have been evaluated as sources of technology innovation in the NSE area over the 28-year period. Each of the most influential articles was cited about 90 times on the average, while the most influential author was cited more than 700 times by the NSE-related patents. Thirteen mainstream journals accounted for about 20% of all citations. Science, Nature and Proceedings of the National Academy of Sciences (PNAS) have consistently been the top three most cited journals, with each article being cited three times on average. There is another kind of influential journals, represented by Biosystems and Origin of Life, which have very few articles cited but with exceptionally high frequencies. The number of academic citations per year from ten most cited journals has increased by over 17 times in the interval (1990-1999) as compared to (1976-1989), and again over 3 times in the interval (2000-2004) as compared to (1990-1999). This is an indication of increased used of academic knowledge creation in the NSE-related patents
[en] There is a significant body of literature concerning the potential formation of electrically conductive moieties in polymeric materials. The conductive path is not associated with conjugation (such as in the case of 'conductive polymers') but rather associated with a new conductivity route. The objective of the experiments reported herein was to provide insight into the phenomenon of unusually high electrical conductivity in polymers that have been reported by several research groups. In some experiments, the test apparatus did indeed indicate high levels of conductance. Arguments pro and con for high conductivity based on known physical phenomena and the collected data were examined.
[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.