2,219 research outputs found

    Solar thermal energy receiver

    Get PDF
    A plurality of heat pipes in a shell receive concentrated solar energy and transfer the energy to a heat activated system. To provide for even distribution of the energy despite uneven impingement of solar energy on the heat pipes, absence of solar energy at times, or failure of one or more of the heat pipes, energy storage means are disposed on the heat pipes which extend through a heat pipe thermal coupling means into the heat activated device. To enhance energy transfer to the heat activated device, the heat pipe coupling cavity means may be provided with extensions into the device. For use with a Stirling engine having passages for working gas, heat transfer members may be positioned to contact the gas and the heat pipes. The shell may be divided into sections by transverse walls. To prevent cavity working fluid from collecting in the extensions, a porous body is positioned in the cavity

    Evidence against memorial facilitation and context-dependent memory effects through the chewing of gum

    Get PDF
    The experiment examined the prediction that chewing gum at learning and/or recall facilitated subsequent word recall. Chewing gum at learning significantly impaired recall, indicating that the chewing of gum has a detrimental impact upon initial word encoding. In addition, a context-dependent memory effect was reported for those participants who both learned and recalled in the absence of gum, however a context dependent effect was not found with chewing gum. The findings contradict previous research

    Chewing gum and context-dependent memory: The independent roles of chewing gum and mint flavour

    Get PDF
    Two experiments independently investigated the basis of the chewing-gum induced context-dependent memory effect (Baker et al, 2004). At learning and/or recall participants either chewed flavourless gum (Experiment 1) or received mint-flavoured strips (Experiment 2). No context dependent memory effect was found with either flavourless gum or mint-flavoured strips, indicating that independently the contexts were insufficiently salient to induce the effect. This is found despite participants’ subjective ratings indicating a perceived change in state following administration of flavourless gum or mint-flavoured strips. Additionally, some preliminary evidence for a non-additive facilitative effect of receiving gum or flavour at either learning and/or recall is reported. The findings raise further concerns regarding the robustness of the previously reported context-dependent memory effect with chewing gum

    A heat receiver design for solar dynamic space power systems

    Get PDF
    An advanced heat pipe receiver designed for a solar dynamic space power system is described. The power system consists of a solar concentrator, solar heat receiver, Stirling heat engine, linear alternator and waste heat radiator. The solar concentrator focuses the sun's energy into a heat receiver. The engine and alternator convert a portion of this energy to electric power and the remaining heat is rejected by a waste heat radiator. Primary liquid metal heat pipes transport heat energy to the Stirling engine. Thermal energy storage allows this power system to operate during the shade portion of an orbit. Lithium fluoride/calcium fluoride eutectic is the thermal energy storage material. Thermal energy storage canisters are attached to the midsection of each heat pipe. The primary heat pipes pass through a secondary vapor cavity heat pipe near the engine and receiver interface. The secondary vapor cavity heat pipe serves three important functions. First, it smooths out hot spots in the solar cavity and provides even distribution of heat to the engine. Second, the event of a heat pipe failure, the secondary heat pipe cavity can efficiently transfer heat from other operating primary heat pipes to the engine heat exchanger of the defunct heat pipe. Third, the secondary heat pipe vapor cavity reduces temperature drops caused by heat flow into the engine. This unique design provides a high level of reliability and performance

    Design of a scientific probe for obtaining Mars surface material

    Get PDF
    The objective is to return a 1 Kg Martian soil sample from the surface of Mars to a mothership in a 60 km Mars orbit. Given here is information on the mission profile, the structural design and component placement, thermal control and guidance, propulsion systems, orbital mechanics, and specialized structures

    Effects of copper on the cupellation of silver

    Get PDF
    The object of this work is to find the effect of copper in the cupellation of silver. Our method of attack was: 1st. To find the effect of varying the amount of copper with constant lead and constant temperature. 2nd. Effect in cupellation of varying the temperature and the lead in the presence of a constant amount of copper. 3rd. To determine the rate at which the copper is removed during cupellation --page 1

    Parents with complicated lives: do child protection services help or hinder?

    Get PDF
    This paper will outline a research project which seeks to centre the voices of parents who have been involved with Child Protection services. The need for a study which focuses on the experiences of service users who have ‘complicated lives’ is discussed with reference to some literature about the intersection of child protection with multiple difficulties relating to violence, disability and problematic substance use. The term ‘complicated lives’ is drawn from the work of Liz Kelly (2000). She uses this expression in her analysis of the systemic constraints facing women who experience multiple and repetitive forms of violence and abuse in order to describe the complex and compound difficulties that may characterise people’s lives. We have chosen to use the term ‘complicated lives’ because it enables us to purposefully avoid pathologising approaches and language which rigidly categorise and stigmatise those with such experiences. Australian research confirms the significant extent to which parents who come to the attention of statutory child protection services are experiencing multiple difficulties. In up to 75% of child protection cases, parents experience problematic substance use, a physical, psychiatric or intellectual disability or ‘family violence’ (Community Care Division, Victorian Government Department of Human Services 2002). The Inquiry into Children in Institutional Care reports an increase in child protection applications resulting from parental issues with substance use, mental illness and/or violence (Senate Community Affairs Committee 2005). Child protection figures from the Australian Institute for Health and Welfare show that 44% of such parents experience two or more of these problems (Australian Institute for Health and Welfare 2003)

    Chewing gum and impasse-induced self-reported stress

    Get PDF
    An insoluble anagram task (Zellner et al., 2006) was used to investigate the proposition that chewing gum reduces self-rated stress (Scholey et al., 2009). Using a between-participants design, forty participants performed an insoluble anagram task followed by a soluble anagram task. These tasks were performed with or without chewing gum. Self-rated measures were taken at baseline, post-stressor, and post-recovery task. The insoluble anagram task was found to amplify stress in terms of increases in self-rated stress and reductions in both self-rated calmness and contentedness. However, chewing gum was found not to mediate the level of stress experienced. Furthermore, chewing gum did not result in superior performance on the soluble anagram task. The present study fails to generalise the findings of Scholey et al. to an impasse induced stress that has social components. The explanation for the discrepancy with Scholey et al. is unclear; however, it is suggested that the impossibility of the insoluble anagram task may negate any secondary stress reducing benefits arising from chewing gum-induced task improvement
    • …
    corecore