Structural and optical properties of thin-film GeSi alloy with Ag nanoparticles obtained by ion implantation and laser irradiation

В данной работе впервые изучено влияние импульсного лазерного отжига (ИЛО) излучением рубинового лазера на слои монокристаллического Si, имплантированного ионами Ge+и Ag+, с целью создания кристаллического композитного плазмонного материала Ag:GeSi. Изучена трансформация структуры слоя и его оптического отражения в зависимости от режимов отжига.In this work for the first time the effect of pulsed laser annealing by ruby laser radiation to monocrystalline Si layers implanted by Ge+and Ag+ ions in order to produce crystalline composite plasmonic Ag:GeSi material is studied. The transformation of layer structure and its optical reflectance depending on annealing regimes is investigated.Работа выполнена при финансовой поддержке РНФ № 17-12-01176

Investigating First-Year Chemistry Students Perception of the Relevance of Practicals at the University of the South Pacific, Fiji

BACKGROUND The laboratory component of any science course is a long established way of teaching students more than just concepts. Laboratories provide ways to not only visualise and strengthen theories learned in the classroom, but to gain agility in handling laboratory equipment. The University of the South Pacific (USP) is a regional university owned by 12 member countries, supported through 14 campuses spread over an area of 30 million square kilometers of the Pacific Ocean, with 20,000 students enrolled. At USP, CH102 (Reactions/Principles of Organic Chemistry) is delivered as a compulsory first year course for those who wish to complete a Bachelor of Science (BSc) Degree Program, with a major or minor in chemistry. AIMS In this investigation, we seek to analyse and rationalise the thoughts, experiences and perceptions of chemistry practicals by undergraduate students at USP. DESIGN AND METHODS This study involved using a questionnaire based survey (with ethics approval) that involved a mix of qualitative and quantitative responses. It contained 10 questions as described by Naiker, Wakeling and Aldred (2013), with the key changes being: in question 5 the weighting was 20 % not 32% and the Chemistry course being CH102; in question 9 the ‘other assessable components’ referred to were tutorials and tests. The questionnaire was given to first year chemistry students from the University of the South Pacific, Fiji, who were recruited to complete the survey (hard-copy) during their second week of Semester 2 in 2012. Descriptive statistics were formulated and qualitative results were grouped by theme, with quantitative data analysed using a Likert scale (1 lowest -5 highest). RESULTS The response rate for the survey was 58% (121/209 students) and there was overwhelming agreement (95%) by the students that laboratory practical work is essential for their learning. The key reasons noted were the benefit of seeing things for ‘real’ and skills development, particularly observational, teamwork and specific laboratory and safety skills. Students felt practical activities were more important (88%) to them than tutorial classes and tests. The students disliked having to write practical reports (45%) and would prefer a greater range of topics were covered. Regarding a weighting of 20% for the practical activity, there was a 50:50 split between it being ‘about right’ and students feeling it should be more. While 50% of students saw no barriers to successfully completing laboratory work, the main barrier was related to time management and completing reports. The key area where students felt their practical experience could be improved was in providing in-depth pre-laboratory explanations to better prepare the students and also interactive guidance in the laboratory environment to ensure students gained the most from the experience. CONCLUSIONS Laboratory work is considered to be essential to students studying chemistry at USP, with a key reason being that it allows a clear link between theory and practice to be made. The high regard students place on laboratory work should be balanced by an assessment weighting that reflects its importance. Importantly, students see laboratory work as providing key skills vital to their overall success. REFERENCES Naiker, M., Wakeling, L., Aldred, P. (2013). The relevance of chemistry practicals – first year student’s perspective at a regional university in Victoria, Australia. Proceedings of the Australian Conference on Science and Mathematics Education, Australian National University, September 19th to September 21st, page 169-173

Seamless navigation in GPS-denied environment using Lirhot's real time north finding sensor

This paper presents a new type of north finding sensor. The passive optical sensor captures images of the sky at a high frame rate and analyzes them into a polarized map of the sky with a high degree of accuracy. The sensor operates in real time, under various weather and atmospheric conditions. The sensor output shows high heading accuracy relative to the celestial true north. Based upon the NAS-14V2 astronomical method of navigation, it is possible to define the sensor global position on earth

Aspectes legals aplicables a les begudes energètiques, riscos i acceptació per part del consumidor

[ES] El consumo de bebidas energéticas por parte de determinados colectivos puede resultar contraproducente para la salud. El acceso a este tipo de productos hace que se tenga que tener en cuenta cuál es la regulación, la indicación de una edad determinada y los riesgos en el etiquetado para su consumo. En este trabajo se analizará la aplicación de la legislación sobre bebidas energéticas, así como la normativa en materia de publicidad para determinar si se cumplen las indicaciones legales sobre este tipo de bebida que se consume por el componente estimulante, el mayor rendimiento cognitivo, y si se indica en el etiquetado los riesgos que puede determinar para el consumidor este tipo de productos.[EN] The consumption of energy drinks by certain groups may be negative for health. Access to this type of product means that it is necessary to take into account its regulation, the indication of a certain age and the risks in the labeling for its consumption. In this work, the application of the legislation on energy drinks will be analyzed, as well as the regulations on advertising to determine if the legal indications on this type of drink that is consumed due to the stimulant component, the greater cognitive performance, and if the labeling indicates the risks that this type of product may cause for the consumer.Granero Lloria, V. (2023). Aspectos legales aplicables a las bebidas energéticas, riesgos y aceptación por parte del consumidor. Universitat Politècnica de València. http://hdl.handle.net/10251/19833

­Que venga la luz!

Contiene: Propuesta didáctica y cuaderno de claseUnidad didáctica que propone al alumnado cuestiones referidas al ámbito de la electricidad. Pretende poner en contacto al alumnado del segundo ciclo de educación primaria con una estrategia de aprendizaje eminentemente experimental y manipulativa que le permita la reestructuración de sus conocimientos sobre el tema y posibilita la integración de la ciencia en el entorno social.ValenciaBiblioteca de Educación del Ministerio de Educación, Cultura y Deporte; Calle San Agustín, 5; 28014 Madrid; Tel. +34917748000; [email protected]