307 research outputs found

    Development and optimization of a method for analyzing biodiesel mixtures with non-aqueous reversed phase liquid chromatography

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    Biodiesel (a mixture of fatty acid esters) is normally analyzed using gas chromatography/flame ionization detection, as specified by the ASTM D6584 and EN14105 standards. This paper proposes a binary gradient method for analyzing biodiesel mixtures using non-aqueous reverse phase HPLC with a UV detector capable of overcoming the drawbacks of the gas chromatographic technique normally used. The new analytical method was developed by means of a statistical sensitivity analysis applied to the main parameters influencing the recording, using the full factorial design method combined with the Yates algorithm and the steepest ascent optimization procedure. The present study shows the influence of the main biodiesel mixture separation analysis parameters. The resulting tool proved valid for analyzing not only biodiesel but also any traces of unreacted oil

    Demand Side Management analysis of a commercial Water Loop Heat Pump system

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    Demand side management (DSM) can be defined as a set of measures adopted to modify customers\u2019 energy demand with the aim of improving the efficiency of the overall energy system. Indeed, DSM strategies can be used to reduce customers\u2019 demand at peak times, reduce energy consumption seasonally/yearly, change the timing of end-use consumption from high to low-cost periods, and increase consumption during off-peak periods. DSM strategies can be implemented by using the energy flexibility available in the final users\u2019 applications, e.g. the thermal inertia of the building mass, the presence of additional energy storage systems enabling load shaping or the use of control systems to turn on/off end-users\u2019 devices when required. Being intensive energy consumers because of a high electric energy demand (mainly for refrigeration, which accounts for about 40 % of the yearly energy consumption), supermarkets are ideal candidates for energy use optimizations obtained through a DSM approach. This work shows the results of a DSM analysis carried out for a refrigeration and HVAC plant in a supermarket coupled with a Water Loop Heat Pump (WLHP) system. The water loop is used as a heat source/sink for the refrigeration unit supplying the cooling capacity required by food preservation and for several heat pumps that provide heating/cooling inside the supermarket building. The system is modelled in TRNSYS and the role of the water loop and its thermal inertia to provide energy flexibility is investigated. The system design and control strategy are modified in order to reduce the electricity costs in presence of demand response programs based on real-time price mechanisms

    Singularity and consciousness: A neuropsychological contribution

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    none6siIn common sense experience based on introspection, consciousness is singular. There is only one ‘me’ and that is the one that is conscious. This means that ‘singularity’ is a defining aspect of ‘consciousness’. However, the three main theories of consciousness, Integrated Information, Global Workspace and Recurrent Processing theory, are generally not very clear on this issue. These theories have traditionally relied heavily on neuropsychological observations and have interpreted various disorders, such as anosognosia, neglect and split-brain as impairments in conscious awareness without any reference to ‘the singularity’. In this review, we will re-examine the theoretical implications of these impairments in conscious awareness and propose a new way how to conceptualize consciousness of singularity. We will argue that the subjective feeling of singularity can coexist with several disunified conscious experiences. Singularity awareness may only come into existence due to environmental response constraints. That is, perceptual, language, memory, attentional and motor processes may largely proceed unintegrated in parallel, whereas a sense of unity only arises when organisms need to respond coherently constrained by the affordances of the environment. Next, we examine from this perspective psychiatric disorders and psycho-active drugs. Finally, we present a first attempt to test this hypothesis with a resting state imaging experiment in a split-brain patient. The results suggest that there is substantial coherence of activation across the two hemispheres. These data show that a complete lesioning of the corpus callosum does not, in general, alter the resting state networks of the brain. Thus, we propose that we have separate systems in the brain that generate distributed conscious. The sense of singularity, the experience of a ‘Me-ness’, emerges in the interaction between the world This is an open access article under the terms of the Creative Commons Attribution-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited and no modifications or adaptations are made. and response-planning systems, and this leads to coherent activation in the different functional networks across the cortex.openHaan, Edward H. F.; Scholte, Huibert Steven; Pinto, Yair; Foschi, Nicoletta; Polonara, Gabriele; Fabri, MaraHaan, Edward H. F.; Scholte, Huibert Steven; Pinto, Yair; Foschi, Nicoletta; Polonara, Gabriele; Fabri, Mar
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