E_{10} Symmetry in One-dimensional Supergravity

We consider dimensional reduction of the eleven-dimensional supergravity to less than four dimensions. The three-dimensional $E_{8(+8)}/SO(16)$ nonlinear sigma model is derived by direct dimensional reduction from eleven dimensions. In two dimensions we explicitly check that the Matzner-Misner-type $SL(2,R)$ symmetry, together with the $E_8$, satisfies the generating relations of $E_9$ under the generalized Geroch compatibility (hypersurface-orthogonality) condition. We further show that an extra $SL(2,R)$ symmetry, which is newly present upon reduction to one dimension, extends the symmetry algebra to a real form of $E_{10}$. The new $SL(2,R)$ acts on certain plane wave solutions propagating at the speed of light. To show that this $SL(2,R)$ cannot be expressed in terms of the old $E_9$ but truly enlarges the symmetry, we compactify the final two dimensions on a two-torus and confirm that it changes the conformal structure of this two-torus.Comment: 33 pages, 3 figures. The action of the Chevalley generators of SL(2,R)_8 is corrected. Commutativity of SL(2,R)_0 and SL(2,R)_8 is checked in detail. The generalized Geroch compatibility (hypersurface-orthogonality) condition is derive

Classical Symmetries of Some Two-Dimensional Models Coupled to Gravity

This paper is a sequel to one in which we examined the affine symmetry algebras of arbitrary classical principal chiral models and symmetric space models in two dimensions. It examines the extension of those results in the presence of gravity. The main result is that even though the symmetry transformations of the fields depend on the gravitational background, the symmetry algebras of these classical theories are completely unchanged by the presence of arbitrary gravitational backgrounds. On the other hand, we are unable to generalize the Virasoro symmetries of the flat-space theories to theories with gravity.Comment: 22 pages, late

Kinetics of tetrabromobisphenol A pyrolysis. Comparison between correlation and mechanistic models

Brominated flame retardants are well recognized as being highly effective flame retardants. 4-4′-Isopropylidenebis(2,6-dibromophenol), commonly known as tetrabromobisphenol A, is the brominated flame retardant with the largest production volume and is used to improve fire safety, mainly of laminates in electrical and electronic equipment. A kinetic study of the pyrolysis of TBBA has been carried out to obtain decomposition parameters under different operating conditions and taking into account that TBBA is a compound with a high boiling point and that vaporization occurs simultaneously to decomposition. Dynamic runs and dynamic + isothermal run at different heating rates and using different masses of sample were correlated simultaneously. All TG runs were fitted with a unique set of kinetic parameters that is able to explain all the experiments. Moreover, a simplified detailed kinetic model has been developed and the kinetic parameters obtained satisfactorily reproduce the thermal decomposition of TBBA.Support for this work was provided by PROMETEO/2009/043/FEDER and ACOMP2011/224 of Generalitat Valenciana (Spain) and CTQ2008-05520 (Spanish MCI/research)

The 'mighty girl' effect: does parenting daughters alter attitudes towards gender norms?

We study the effect of parenting daughters on attitudes towards gender norms in the UK; specifically, attitudes towards the traditional male breadwinner norm in which it is the husband's role to work and the wife's to stay at home. We find robust evidence that rearing daughters decreases fathers' likelihood to hold traditional attitudes. This result is driven by fathers of school-aged daughters, for whom the effects are robust to the inclusion of individual fixed effects. Our estimates suggest that fathers' probability to support traditional gender norms declines by approximately 3%age points (8%) when parenting primary school-aged daughters and by 4%age points (11%) when parenting secondary school-aged daughters. The effect on mothers' attitudes is generally not statistically significant. These findings are consistent with exposure and identity theories. We conclude that gender norm attitudes are not stable throughout the life-course and can significantly be shaped by adulthood experiences

Thermogravimetric Study of the Decomposition of Printed Circuit Boards from Mobile Phones

Paper submitted to the 19th International Symposium on Analytical & Applied Pyrolysis, Linz, Austria, 21-25 May 2012.Printed circuit boards (PCB) are particularly problematic to recycle because of the heterogeneous mix of organic material, metals, and glass fibre. More specifically, the presence of Fe and Cu can catalyze the debromination/hydrogenation reaction, accelerating the formation of chlorinated and brominated dioxins and furans.Ministry of Education and Science (Spain): CTQ2008-05520; Valencian Community Government (Spain): PROMETEO/2009/043/FEDER and ACOMP2011/224

Effect of Temperature, Atmosphere and Metals on the Thermal Degradation of Printed Circuit Boards

The permanent expansion of the market of electrical and electronic equipment (EEE) and the shorter innovation cycles, lead to a faster replacement of these appliances, making EEE a fast-growing source of waste (WEEE). As stated in Directive 2012/19/EU1 on waste electrical and electronic equipment, the content of hazardous components in EEE is a major concern during the waste management phase, and recycling of WEEE is not currently undertaken to a sufficient extent, resulting in a loss of valuable resources.Support for this work was provided by: Ministry of Education and Science (Spain) (CTQ2008-05520 project); Valencian Community Government (Spain) (PROMETEO/2009/043/FEDER project)

Pirólisis y combustión de residuos electrónicos

Resumen de la comunicación presentada en el I Congreso de Estudiantes de Ingeniería Química de la Universidad de Alicante, 13-14 abril 2010.Los costes de producción cada vez menores y el aumento de la disponibilidad de equipos electrónicos de todo tipo, incluyendo teléfonos móviles, equipos de audio y vídeo y ordenadores personales, así como sus accesorios, unido a los avances en tecnología que hacen que estos productos queden rápidamente obsoletos, supone un problema de creciente importancia. A este respecto, la Directiva 2002/96/CE del Parlamento Europeo y del Consejo de 27 de enero de 2003 sobre residuos de aparatos eléctricos y electrónicos (RAEE) regula la gestión y eliminación de estos residuos por separado, promoviendo su reutilización, reciclado y recuperación.Las ayudas para la realización de este trabajo proceden de los proyectos CTQ2008-05520 de Ministerio de Educación, Prometeo/2009/043 y ACOM2009/135 de la Generalitat Valenciana

Kinetics of pyrolysis and combustion of pine needles and cones

A wide kinetic study has been carried out under different conditions in TG and TG–MS for each material, at different operating conditions. Runs were carried out at three different atmospheres: N2, N2:O2 4:1 and N2:O2 9:1. In addition to the dynamic runs carried out at constant heating rate, other runs were performed in an isothermal regime (constant heating rate until the set temperature is reached and then the set temperature is maintained constant). In addition, a study of the thermal decomposition for both materials was also carried out in a dynamic run using TG–MS in order to observe the evolution of the major compounds and to discuss the information that could be obtained. From the overall analysis of the data, schemes of reactions and kinetic values were calculated by integration of the differential equations and minimizing the squared differences between the experimental and calculated values. It is important to emphasise that the same set of parameters is proposed for the runs for each material, and depends on neither the heating rate in dynamic runs nor whether the run is carried out in a dynamic or isothermal mode.Support for this work was provided by Spanish MEC, research project CTQ2005-05262

Emissions from the Pyrolysis and Combustion of Different Wastes

Paper submitted to the 7th International Symposium on Feedstock Recycling of Polymeric Materials (7th ISFR 2013), New Delhi, India, 23-26 October 2013.A comparison between different emission rates of various pollutants obtained from various wastes is presented. The studied wastes were the following: polyethylene, tyres, sewage sludge, polyvinyl chloride, cotton textiles, polyester textiles, meat and bone meals, varnish wastes, olive oil solid waste (pomace), waste lube oils, paper waste, tomato plant, pine needles and cones, mobile phones and automotive shredder residue. The decomposition of these wastes was studied in a horizontal laboratory scale reactor at 850 ºC in an inert and an oxidizing atmosphere, and the analysis of the pollutants evolved comprised several compounds such as light hydrocarbons, PAHs and PCDD/Fs.Ministry of Education and Science (Spain) (CTQ2008-05520 project) and Valencian Community Government (Spain) (PROMETEO/2009/043/FEDER project)

Mechanistic studies on the photogeneration of o- and p-xylylenes from α,α'-dichloroxylenes

Two-colour two-laser techniques have unambiguously proved that photolysis of the o-/p-(chloromethyl)benzyl radical leads to the sequential two-photon generation of o-/pxylylene from α,α'-dichloro-o-/p-xylene.Perez Prieto, Julia, [email protected]