875 resultados para Choruses, Sacred (Mixed voices) with instrumental ensemble


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Water retention and transport in soils is dependent upon the surface tension of the aqueous phase. Surfactants present in aqueous solution reduce the surface tension of aqueous phase. In soil–water systems, this can result in water drainage and reductions in field capacity and hydraulic conductivity. In this investigation, the surface tension of surfactant solutions mixed with soil—in a constant fixed ratio—was measured as a function of surfactant concentration. Two anionic surfactants were used: sodium dodecyl sulphate and sodium bis (2-ethylhexyl) sulfosuccinate. Two soils were also used—a clay soil and a sandy soil. The key observation made by this investigation was that the addition of soil to the surfactant solution provided a further component of surface tension reduction. Neither soil sample reduced the surface tension of water when surfactant was absent from the aqueous phase, though both soils released soil organic matter at low surfactant concentrations as shown by measurement of the chemical oxygen demand of the supernatant solutions. Furthermore, both surfactants were shown to be weakly adsorbed by soil as shown by the use of a methylene blue assay. It is therefore proposed that the additional reduction in surface tension arises from synergistic interactions between the surfactants and dissolved soil organic matter.

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We assess the fortunes of Irish unions since 1980 and, in particular, focus on the period of national social partnership since 1987. We argue that, structurally, unions have been weakened by a sharp decline in union density levels. In addition, labor law reform has not been as permissive as unions desired. However, on the other hand, we highlight that union membership in Ireland has never been higher and unions exert a strong influence over many areas of government policy. In conclusion, we argue that continuing with social partnership is the most viable option for Irish unions, though significant gains in union power are unlikely to happen.

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The activity and nature (i e heterogeneous and/or homogeneous) of catalysts based on CsF supported on alpha-Al2O3 were investigated for the transesterification of vegetable oil with methanol. The effect of the activation temperature, CsF loading and the reusability in a recirculating reactor were first studied CsF/alpha-Al2O3 exhibited the highest activity for a CsF loading of 0 6 mmol/g and when activated at 120 degrees C An important aspect of this study is the effect of CsF leaching into the reaction mixture, which is attributed to the high solubility of CsF in methanol, leading to a complete loss of activity after one run It was Identified that the activity of the catalyst resulted from a synergy between alumina and dissolved CsF, the presence of both compounds being absolutely necessary to observe any conversion The use of an alumina with a higher surface area resulted in a far greater reaction rate, showing that the concentration of surface site on the oxide (probably surface hydroxyl) was rate-limiting in the case of the experiments using the low surface area alpha-Al2O3 This work emphasizes that combined homogeneous-heterogeneous catalytic systems made from the blending of the respective catalysts can be used to obtain high conversion of vegetable oil to biodiesel. Despite the homogeneous/heterogeneous dual character, such a catalytic system may prove valuable in developing a simple and cost-effective continuous catalytic process for biodiesel production (C) 2010 Elsevier B V All rights reserved

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The work ROTATING BRAINS / BEATING HEART was specifically developed for the opening performance of the 2010 DRHA conference. The conference’s theme ‘Sensual Technologies: Collaborative Practices of Interdisciplinarity explored collaborative relationships between the body and sensual/sensing technologies across various disciplines, looking to new approaches offered by various emerging fields and practices that incorporate new and existing technologies. The conference had a specific focus on SecondLife with roundtable events and discussions, led by performance artist Stelarc, as well as international participation via SecondLife.
The collaboration between Stelarc, the Avatar Orchestra Metaverse (AOM) and myself as the DRHA2010 conference program chair was a unique occurrence for this conference.

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Here we report an example of a mixed thiol monolayer on the surface of Ag nanoparticles which promotes adsorption and quantitative SERS detection of 3,4-methylenedioxymethamphetamine (MDMA, “Ecstasy”); the thiols in the mixed monolayers act synergistically since MDMA does not adsorb onto colloids modified with either of the thiols separately.

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This output is a collection of compositions which explore issues of ensemble improvisation, ensemble management and orchestration, real-time and distributed scoring, multi-nodal inputs and outputs, and animated and graphic notation. Compositions include: Activities I; tutti, duet, trio, solo, quartet; Lewitt Notations I; Webwork I; and Sometimes I feel the space between people (voices) in terms of tempos. These compositions are presented in computer animated scores which are synchronized through the network and subject to real-time modification and control. They can be performed by ensembles distributed over large physical spaces connected by the network. The scores for these compositions include software which displays the animations to the performers, software to structure and disseminate score events, and triggering software that allows the control of a performance to be distributed. Scores can also include live electronics which are coordinated with graphic events.

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Acetylene coupling to benzene on the Pd(lll) surface is greatly enhanced by the presence of catalytically inert Au atoms. LEED and Auger spectroscopy show that progressive annealing of Au overlayers on Pd(lll) leads to the formation of a series of random surface alloys with continuously varying composition. Cyclization activity is a strong function of surface composition-the most efficient catalyst corresponds to a surface of composition similar to 85% Pd. CO TPD and HREELS data show that acetylene cyclization activity is not correlated with the availability of singleton Pd atoms, nor just with the presence of 3-fold pure Pd sites-the preferred chemisorption site for C2H2 on Pd{111}. The data can be quantitatively rationalized in terms of a simple model in which catalytic activity is dominated by Pd6Au and Pd-7 surface ensembles, allowance being made for the known degree to which pure Pd{111} decomposes the reactant and product molecules.

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Biosignal measurement and processing is increasingly being deployed in ambulatory situations particularly in connected health applications. Such an environment dramatically increases the likelihood of artifacts which can occlude features of interest and reduce the quality of information available in the signal. If multichannel recordings are available for a given signal source, then there are currently a considerable range of methods which can suppress or in some cases remove the distorting effect of such artifacts. There are, however, considerably fewer techniques available if only a single-channel measurement is available and yet single-channel measurements are important where minimal instrumentation complexity is required. This paper describes a novel artifact removal technique for use in such a context. The technique known as ensemble empirical mode decomposition with canonical correlation analysis (EEMD-CCA) is capable of operating on single-channel measurements. The EEMD technique is first used to decompose the single-channel signal into a multidimensional signal. The CCA technique is then employed to isolate the artifact components from the underlying signal using second-order statistics. The new technique is tested against the currently available wavelet denoising and EEMD-ICA techniques using both electroencephalography and functional near-infrared spectroscopy data and is shown to produce significantly improved results. © 1964-2012 IEEE.

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This article provides a reflection on my past practice as Creative Director of The Mixed Peppers Theatre Arts Training Programme. Drawing upon discourses of Disability Studies it considers how this ostensibly emancipatory project that sought to provide access to theatre activity for young people with physical disabilities living in Northern Ireland was flawed, and was eventually disbanded, partly due to a failure on the part of its non-disabled leadership to address imbalances of power in its relationship with its young disabled constituency. The article is framed within a survey of recent debates that focus upon the historical lack of a sustained, indigenous, disability-led theatre activity in Northern Ireland and the recent efforts by non-disabled professional arts practitioners to establish such activity in the region. It offers, as an exemplar to current discussion, an analysis of how the choice and agency of the young members of The Mixed Peppers were compromised by the well-meaning but potentially oppressive practices of its leadership. It questions whether the project was unduly influenced by parental desire to see their disabled children `normalized' in a high-profile theatrical production. Finally, it considers how The Mixed Peppers' institutional situation, as a project controlled and administered by a disability charity, was implicated in the premature demise of the initiative.