HC

To identify long term replacement for the existing refrigerant, system performance should not be compromised, refrigerant and lubrication interaction should be as required, it should be environment friendly, energy efficient etc. So there is need to find out a refrigerant which is environment friendly, such as hydrocarbon (HC) refrigerants used in refrigeration and air conditioning systems and which can be used long term substitute for existing refrigerants. The most important caveat for developing new refrigerants is its low ozone depleting potential (ODP) and global warming potential (GWP). Though HC refrigerants are highly flammable, they have several preferable features such as zero ozone depletion potential(ODP), very low global warming(GWP), non-toxicity and higher performance than other refrigerant types but also high miscibility with mineral oil and good accordance with the existing refrigerating systems. They are used in many applications with safety of the leakage from the system also with these refrigerants it was found that, there was no need to change in the design of the refrigeration system. So we can look forward to HC refrigerants as best substitute refrigerant.

The concept of 'uneven and combined development' was originally coined by Leon Trotsky to theorise Tsarist Russia's distinctive experience of modernity and revolution. But it has re-emerged over the last decade or so as a burgeoning research programme within International Relations (IR) and historical sociology. It has been critically and creatively deployed in two main areas: the provision of a sociological foundation to international theory overcoming the chronic schism between ‘sociological’ and ‘geopolitical’ modes of enquiry; and, relatedly, in superseding prevailing Eurocentric approaches in the social sciences. This volume is the first to provide a sustained reflection on the idea of uneven and combined development as the intellectual basis for a non-Eurocentric social theory of ‘the international’. It does so through a series of empirically rich and theoretically informed analyses of socio-historical change, political transformation, and intersocietal conflict ov...

Este estudo procurou investigar como a estrategia didatica da resolucao de situacoes-problema pode auxiliar no aprendizado de conceitos pelos alunos da 8a serie/ 9o ano do Ensino Fundamental de uma escola da rede Estadual de Calumbi, Pernambuco. Para isso, a partir das indicacoes propostas por Merieu (1998), foi elaborada, uma Situacao-problema, que teve sua tematica ligada ao efeito estufa. A obtencao dos dados foi feita usando, entre outros instrumentos, questionario impresso e entrevista semiestruturada (gravada em audio) com o professor de ciencias, e um questionario aplicado a dez alunos, apos a intervencao em sala de aula. A atividade realizada permitiu ao docente uma reflexao acerca do uso de situacoes-problema como estrategia didatica, alem de alguns aportes teoricos que fundamentam a abordagem de uso destas. As respostas dos alunos mostraram que houve de forma significativa a construcao do conhecimento em algum grau, como mostram os dados obtidos depois de analisados adequa...

One of the undesirable emissions from diesel engine is NOx emission. In order to reduce NOx emission exhaust gas recirculation is used. Regulations to reduce NOx emissions continue to become more and more stringent year by year. Exhaust gas recirculation (EGR) is one of the techniques used to reduce nitrogen oxides because it lowers flame temperature in the combustion chamber. However as NOx reduces, hydrocarbon (HC) emissions and smoke level increases. As the EGR rate increases the engine operation becomes instable and there is a little reduction in thermal efficiency. Alcohol fumigation is a technique used for reducing emissions and improving the thermal efficiency of the engine. An experimental set up is fabricated to facilitate EGR and ethanol fumigation in the inlet duct of the engine. Engine performance, NOx and HC emissions without EGR, with EGR and with EGR and ethanol fumigation are presented in this work.

ABSTRACTWith the recent rise in global history as a discipline, early modern Europe's Asian trade has become a new focus of interest. In French historiography, however, this still remains marginalized. Some studies of the French East India Companies and the French presence in Asia exist, but the impact of this on metropolitan France remains woefully underexplored. This article outlines the history and historiography of the French East India Companies and their wider role and importance, outlining pathways of both existing, current, and possible future research.

We report the carbon (C) substitution effects of MgB2+10 wt% C4H6O5 (malic acid) on the lattice parameters, critical temperature (Tc), upper critical field (Hc2), and irreversibility field (Hirr) as a function of sintering temperature in the range from 600 to 900 °C. The additive C4H6O5 as the C source resulted in a small depression in Tc, but significantly increased the

In this paper, contributions from scholars working in the field of visual communication and/or online communication are gathered whose scholarly work falls into the BRICS countries realm. The interviews are framed by a brief sketch of the relevance of BRICS countries research in communication and media studies and some prospective comments on this novel field. The contributing scholars in this issue focus on China and Brazil in particular and work across the globe in Germany, the Netherlands, Austria, Switzerland, PR China, the UK and Brazil. They shared their ideas on the subject even though they are scholarly roots lie in fields as diverse as regional studies, political studies, communication and media studies and educational studies. Their thoughts were collected through email interviews and they are presented here in form of a cross-disciplinary dialogue on the issue of visual online communication in BRICS countries and the De-Westernization discourse. Gratefulness goes out to a...