896 resultados para laboratory instruments


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The substitution of petroleum-based fuels with those from renewable sources has gained momentum worldwide. A UV-vis experiment for the quantitative analysis of biofuels (bioethanol or biodiesel) in (petroleum-based) diesel oil has been developed. Before the experiment, students were given a quiz on biofuels, and then they were asked to suggest a suitable UV-vis experiment for the quantification of biofuels in diesel oil. After discussing the results of the quiz, the experiment was conducted. This included the determination of lambda(max) of the medium-dependent, that is, solvatochromic, visible absorption band of the probe 2,6-bis[4-(tert-butyl)phenyl]-4-{2,4,6-tris[4-(tert-butyl)phenyl]pyridinium-1-yl}phenolate as a function of fuel composition. The students appreciated that the subject was linked to a daily situation and that they were asked to suggest the experiment. This experiment served to introduce the phenomena of solvation and solvatochromism.

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The Center for the Study of Free-Reed Instruments Collection is an archival collection at the City University of New York Graduate Center’s Mina Rees Library which contains materials donated by Professor Allan W. Atlas, related to free-reed instruments and the International Concertina Association.

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Several students are shown working in a section of the Television Laboratory at the New York Trade School. Black and white photograph with some damage due to writing in red ink along the long edges.

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The current paper presents a study conducted at CERN, Switzerland, to investigate visitors' and tour guides' use and appreciation of existing panels at visit itinerary points. The results were used to develop a set of recommendations for constructing optimal panels to assist the guides' explanation.

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The goal of primary science education is to foster children’s interest, develop positive science attitudes and promote science process skills development. Learning by playing and discovering provides several opportunities for children to inquiry and understand science based on the first–hand experience. The current research was conducted in the children’s laboratory in Heureka, the Finnish science centre. Young children (aged 7 years) which came from 4 international schools did a set of chemistry experiments in the laboratory. From the results of the cognitive test, the pre-test, the post-test, supported by observation and interview, we could make the conclusion that children enjoyed studying in the laboratory. Chemistry science was interesting and fascinating for young children; no major gender differences were found between boys and girls learning in the science laboratory. Lab work not only encouraged children to explore and investigate science, but also stimulated children’s cognitive development.

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This thesis has been done in ROM (Royal Ontario Museum) located in Toronto Canada. It focuses on learning in two parts of the museum. It tries to find out how much each part is effective in terms of learning. Studies have been done in the Digital gallery, which has been equipped with digital video projector and workstation that allows visitors to interact with the collections in 2 or 3 dimensional spaces while they are watching the presenting film. The rest of the study was in Hands-on laboratory, which allows students to examine artifacts and discuss their findings .The method was used in this research is Concept mapping .In Digital gallery, 24 schools surveys in the form of pre-post- test by help of the concept mapping method has been done. In Hands-on laboratory, 12 schools have been studied by using the combination of interviewing and written pre post-test of concept mapping.

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PAPRO operates within the Forest Research company and their mission is to develop value-addingindustry solutions. At present there are no good ways for mills to easily test the printing quality on newsprintpaper. There is a great need for a fast way to do this on different paper qualities; with a laboratory-offset press this can be both a time and money saving method. At PAPRO Forest Research, NewZealand, a laboratory offset press has been developed and designed, during the past seven years, concerningthis issue. Earlier projects were made concerning the press, e.g. to establish the optimal settings.The mission with this project was to partly determine the present variability of the print quality andto evaluate if the fountain solution, distilled water and 2% Diol green concentrate, used at the momentmixed with different percentages of Isopropanol could decrease the variability and contribute to morestabile results. Throughout the whole project the print quality showed a high variation and was evenmore variable when the Isopropanol was added. All in all 50 print rounds times twelve printed paperstrips was carried out through the project divided into three parts. To analyse the print quality, amicroscope with an image capture camera has been used. Data from the taken images was analysedand inserted into charts to see the variations.The conclusions of the whole project are not satisfying because no final evaluations were possible tomake. Main conclusions are that the additive of Isopropanol to the ordinary fountain solution, used atpresent, only contributed to more unstable results of the print quality. And it seems to be difficult toget some stable results from the lab press as long as the room where it is placed is not fully conditionedas required for the process of offset printing. And the fact that the airbrush which applies theamount of fountain solution is also variable, as shown in earlier projects, which contributes to unstableresults as well. For further work more exact parameters as a conditioned room are required and thepossibility to further design the laboratory press to use waterless offset printing instead.

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The newly adopted energy efficiency directive (2012/27/EU) highlights the importance of energy efficiency in reaching the Union’s 2020 targets. The directive commits member states to defining national energy efficiency targets (art. 3), achieving yearly energy savings of 1.5% of the annual energy sales through the energy efficiency obligation scheme (art. 7), and providing a long-term strategy for the building sector that aims at a 3% refurbishment rate for public buildings (art. 4+5). Buildings currently account for 40% of energy use in most countries, putting them among the largest end-use sectors. This report takes a closer look at the best practices for implementing increasing energy efficiency in different regions and countries in Europe. The final aim is to identify some policy tools to be suggested to the region of Dalarna (Dalarna having been chosen as the pilot county in Sweden) as a means of implementing energy efficiency in the building sector. The final objective is to give analysts and decision-makers a better analytical foundation to explore future policy development in the area of buildings to be proposed and tested at the regional level in Dalarna and later at the national level in Sweden.

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Photograph of students at the Voorhees Technical Institute.

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Photograph of students at the Voorhees Technical Institute.

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Photograph of students at the Voorhees Technical Institute.

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This dissertation deals with the problem of making inference when there is weak identification in models of instrumental variables regression. More specifically we are interested in one-sided hypothesis testing for the coefficient of the endogenous variable when the instruments are weak. The focus is on the conditional tests based on likelihood ratio, score and Wald statistics. Theoretical and numerical work shows that the conditional t-test based on the two-stage least square (2SLS) estimator performs well even when instruments are weakly correlated with the endogenous variable. The conditional approach correct uniformly its size and when the population F-statistic is as small as two, its power is near the power envelopes for similar and non-similar tests. This finding is surprising considering the bad performance of the two-sided conditional t-tests found in Andrews, Moreira and Stock (2007). Given this counter intuitive result, we propose novel two-sided t-tests which are approximately unbiased and can perform as well as the conditional likelihood ratio (CLR) test of Moreira (2003).

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The negotiations of mega agreements between the US and the Pacific countries (TPP) and between the US and the EU (TTIP) are raising the attention of experts on international trade law and economics. TPP and TTIP are proclaimed to be the designers of the rules for the XXI Century. Old trade instruments such as tariffs are said to be no more important for TTIP because tariffs are negligible among those partners but significant to for TPP. Another relevant agreement in negotiation is between the EU and Mercosul, where tariffs are the most important issue in discussion. The main purpose of this paper is to shows that tariff are important for all these agreements, not because of its nominal value, but because the impacts of exchange rate misalignments on tariffs are so significant that all concessions can be distorted by overvalued and by devaluated currencies. The article is divided into several sections: the first gives an introduction to the issue; the second explains the methodologies used to determine exchange rate misalignments and also presents some results for Brazil, US and China; the third summarizes the methodology applied to calculate the impacts of exchange rate misalignments on the level of tariff protection through an exercise of “misalignment tariffication” and examines the effects of exchange rate variations on tariffs and their consequences for the multilateral trading system; the fourth creates a methodology to estimate exchange rates against a basket of currencies (a virtual currency of the World) and a proposal to deal with persistent and significant misalignments related to trade rules. The fifth presents some estimates for the main PTAs. The conclusions are present in the last section

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O completo desenvolvimento larval de Notolopas brasiliensis é descrito, a partir de material criado em laboratório, com ênfase na morfologia externa de Majoidea e comparado aos demais gêneros de Pisidae. O desenvolvimento larval de N. brasiliensis consiste em dois estágios de zoea e um de megalopa. A duração media de cada estágio foi de 4.2 ± 1.0 dias para a Zoea I e 3.8 ± 0.7 dias para a Zoea II, a megalopa aparece entre 8.1 ± 0.4 dias após a eclosão. Os caracteres previamente utilizados para definir as formas larvais de Pisidae ou são simplesiomórficos ou altamente homoplásticos. Foi observado que não existe um conjunto de caracteres capazes de definir Pisidae até o presente.Contudo foi mostrado que uma combinação de caracteres pode ser utilizada para diferenciar Notolopas dos demais gêneros da família.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)