8,280 research outputs found

    Grown organic matter as a fuel raw material resource

    Get PDF
    An extensive search was made on biomass production from the standpoint of climatic zones, water, nutrients, costs and energy requirements for many species. No exotic species were uncovered that gave hope for a bonanza of biomass production under culture, location, and management markedly different from those of existing agricultural concepts. A simulation analysis of biomass production was carried out for six species using conventional production methods, including their production costs and energy requirements. These estimates were compared with data on food, fiber, and feed production. The alternative possibility of using residues from food, feed, or lumber was evaluated. It was concluded that great doubt must be cast on the feasibility of producing grown organic matter for fuel, in competition with food, feed, or fiber. The feasibility of collecting residues may be nearer, but the competition for the residues for return to the soil or cellulosic production is formidable

    The room temperature phosphine-free synthesis of near-infrared emitting HgSe quantum dots

    Get PDF
    Luminescent mercury selenide (HgSe) quantum dots have been synthesised by a phosphine-free method using oleic acid as a capping agent. The modification of experimental conditions such as temperature resulted in particles of various sizes (15–100 nm) and morphologies not previously seen in HgSe, with emission tuneable between 1000 nm and 1350 nm

    Partnerships as a potential means of increasing the production of hardwood timber on NIPF lands in North Mississippi

    Get PDF
    North Mississippi has significant hardwood timber resources. Hardwood timber in the region has traditionally been an important source of raw material for furniture and other wood-based industries. In recent years, however, demand has greatly increased for hardwood timber for use in the pulp and paper industry, resulting in increased harvest levels of pole-sized and small sawtimber-sized hardwoods in the region. Increased harvests of hardwood timber have given rise to concerns about the longerterm availability of hardwoods that are large enough in size to be efficiently converted into lumber and other solid wood products. Futures options, futures contracts, leases, and limited partnerships were initially considered for potential application to increase the longer-term production of hardwood sawtimber on nonindustrial private forest (NIPF) lands in North Mississippi. Considering the resource, the NIPF ownership, and the timber markets involved, limited partnerships were chosen for further evaluation. Results of informal discussions involving hardwood sawmill operators, private landowners, and timberland investment firm representatives are presented. A discussion follows, assessing the acceptability and attributes of partnerships in contrast to other possible options such as long-term leases as a positive influence for investment in the long-term production of hardwood sawtimber in North Mississippi

    Molecular and morphometric variation in European populations of the articulate brachiopod <i>Terebeatulina retusa</i>

    Get PDF
    Molecular and morphometric variation within and between population samples of the articulate brachiopod &lt;i&gt;Terebratulina&lt;/i&gt; spp., collected in 1985-1987 from a Norwegian fjord, sea lochs and costal sites in western Scotland, the southern English Channel (Brittany) and the western Mediterranean, were measured by the analysis of variation in the lengths of mitochondrial DNA (mtDNA) fragments produced by digestion with nine restriction endonucleases and by multivariate statistical analysis of six selected morphometric parameters. Nucleotide difference within each population sample was high. Nucleotide difference between population samples from the Scottish sites, both those that are tidally contiguous and those that appear to be geographically isolated, were not significantly different from zero. Nucleotide differences between the populations samples from Norway, Brittany, Scotland and the western Mediterranean were also very low. Morphometric analysis confirmed the absence of substantial differentiation

    Sexual harassment and abuse in sport: The research context

    Get PDF
    This special issue of the Journal of Sexual Aggression draws on the contributions to a Symposium on ‘Sexual Harassment in Sport – Challenges for Sport Psychology in the New Millennium’, held at the Xth Congress of the International Society for Sport Psychology, Skiathos, Greece from May 28th to June 2nd 2001. The symposium, which was organised by the authors of this editorial, was intended to move forward the international research agenda on sexual harassment and abuse in sport and to examine professional practice issues for sport psychologists. It was clear from the attendance of over 60 delegates at that symposium that international interest in this subject is growing. Further evidence of this came from the attendance of 26 members states – from Azerbaijan to Sweden - at a Council of Europe seminar on The Protection of Children, Young People and Women in Sport, held in Helsinki in September 2001

    Biomechanical Tolerance of Whole Lumbar Spines in Straightened Posture Subjected to Axial Acceleration

    Get PDF
    Quantification of biomechanical tolerance is necessary for injury prediction and protection of vehicular occupants. This study experimentally quantified lumbar spine axial tolerance during accelerative environments simulating a variety of military and civilian scenarios. Intact human lumbar spines (T12‐L5) were dynamically loaded using a custom‐built drop tower. Twenty‐three specimens were tested at sub‐failure and failure levels consisting of peak axial forces between 2.6 and 7.9 kN and corresponding peak accelerations between 7 and 57 g. Military aircraft ejection and helicopter crashes fall within these high axial acceleration ranges. Testing was stopped following injury detection. Both peak force and acceleration were significant (p \u3c 0.0001) injury predictors. Injury probability curves using parametric survival analysis were created for peak acceleration and peak force. Fifty‐percent probability of injury (95%CI) for force and acceleration were 4.5 (3.9–5.2 kN), and 16 (13–19 g). A majority of injuries affected the L1 spinal level. Peak axial forces and accelerations were greater for specimens that sustained multiple injuries or injuries at L2–L5 spinal levels. In general, force‐based tolerance was consistent with previous shorter‐segment lumbar spine testing (3–5 vertebrae), although studies incorporating isolated vertebral bodies reported higher tolerance attributable to a different injury mechanism involving structural failure of the cortical shell. This study identified novel outcomes with regard to injury patterns, wherein more violent exposures produced more injuries in the caudal lumbar spine. This caudal migration was likely attributable to increased injury tolerance at lower lumbar spinal levels and a faster inertial mass recruitment process for high rate load application. Published 2017. This article is a U.S. Government work and is in the public domain in the USA

    Oxide phosphors for light upconversion; Yb3+ and Tm3+ co-doped Y2BaZnO5

    Get PDF
    Copyright 2011 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. This article appeared in Journal of Applied Physics 109, 063104 (2011) and may be found at

    Unchecked box Heat from Underground Energy London (Heat FUEL)

    Get PDF
    This paper aims to introduce a heat recovery scheme that will collect waste energy from the London Underground in Islington, London. The system is based on the installation of an air to water heat exchanger within a ventilation shaft of the London Underground. The heat captured is distributed to a heat pump, which upgrades it to a suitable temperature for reuse and provides low carbon energy to a local district heating network. This paper introduces some of the key aspects of the technical design of this novel urban heat recovery and delivery system. Its theoretical performance is evaluated and compared to the previous heating method used for the buildings supplied by the network. It also provides recommendations for the implementation of future installations for secondary heat recovery and reuse in cities
    • 

    corecore