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Many Phenomena (many + phenomenon)
Selected AbstractsAqueous Foams: A Field of Investigation at the Frontier Between Chemistry and PhysicsCHEMPHYSCHEM, Issue 4 2008Dominique Langevin Dr. Abstract This paper reviews the properties of aqueous foams. The current state of knowledge is summarized briefly and the interdisciplinary aspects of this field of investigation are emphasized. Many phenomena are controlled by physical laws, but they are highly dependent upon the chemicals used as foam stabilizers: surfactants, polymers, particles. Most of the existing work is related to surfactants and polymer foams, and little is known yet for particle foams although research in this field is becoming popular. This article presents the general concepts used to describe the monolayers and the films and also some of the recent advances being made in this area. [source] Heat transfer by radiation and convection in fire testingFIRE AND MATERIALS, Issue 5 2004Ulf Wickström Abstract Fire safety engineers, especially those experts writing fire test standards, often have different understandings of the concepts of heat transfer from a fire to a surface by radiation and convection. The concepts are therefore often not very well defined, in e.g. ISO and CEN standards, leading in many cases to confusions, misunderstandings and considerable errors. This paper is an effort, in a very simple way, to make the issue a little clearer, particularly for use in international standardization work. ISO/TC92 and the International FORUM of Fire Research Directors are currently endorsing very important work on procedures to calibrate heat flux meters. The two entities, heat transfer by radiation and convection, may be treated independently. The presentation below is deliberately very short and basic avoiding many phenomena that are not immediately needed in most fire standardization work. Recommendations are reached on how to define and measure heat transfer in fire testing. Copyright © 2004 John Wiley & Sons, Ltd. [source] Stacking interaction study of trans -resveratrol (trans -3,5,4,-trihydroxystilbene) in solution by Nuclear Magnetic Resonance and Fourier Transform Infrared SpectroscopyMAGNETIC RESONANCE IN CHEMISTRY, Issue 7 2008Claudia Bonechi Abstract Interactions between aromatic rings or other unsaturated systems, including ,-stacking and face-to-edge complexes, are the origin of many phenomena in both organic and biological chemistry. It is well known that these interactions play an important role in the stabilization of the stereo-structure of DNA and the tertiary structure of many proteins. Trans -resveratrol (trans -3,5,4,-trihydroxystilbene, trans -RSV) is a phytoalexin found in Vitis sp. and in many other plants and food products and has received much attention because of its possible positive health benefits. In this work, the ,-stacking interaction of trans -RSV was studied by nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectroscopy. In particular, the proton chemical shift dependence of the RSV concentration in the range 2 × 10,2 , 1 × 10,5M and temperature were analysed. Moreover, the dynamics of the supramolecular aggregates were studied by nuclear spin relaxation data. Copyright © 2008 John Wiley & Sons, Ltd. [source] Examining understanding, acceptance, and support for the biorefinery concept among EU policy-makersBIOFUELS, BIOPRODUCTS AND BIOREFINING, Issue 3 2009Philip Peck Abstract This paper outlines how an understanding of the processes of building cognitive and sociopolitical legitimacy is relevant to the formation of a biorefining sector. First we describe a number of theoretical insights into challenges faced by emerging industries and how these can relate to the formation of a biorefining sector. Second, we present the conduct and results of an initial exploration of understanding, acceptance, and support for the biorefinery concept among a sample of actors in the EU policy community. General conclusions of this study are then provided in these two areas. Addressing theory versus evidence from the fi eld, it is found that many phenomena predicted by theory indeed appear in the empirical results and seem immediately relevant to the formative biorefining industry. Analysis of the perceptions of members of the policy community toward biorefinery-related environmental, social, policy, reputational and policy issues reveals that there are a number of areas where prompt action from the political and scientifi c communities could yield signifi cant benefi ts. We conclude that theories enfolding the concepts of cognitive and sociopolitical legitimacy are relevant to discussions of biofuels, bioproducts and biorefining. Importantly, proponents of the biorefinery concept can draw upon a broad body of knowledge generated in both related and non-related industries, to support their work reducing barriers to the emergence of commercial biorefineries. A key area in this regard will be improved communication of biorefinery contributions to sustainable development. © 2009 Society of Chemical Industry and John Wiley & Sons, Ltd [source] | ||||||||||