2,984 research outputs found

    Grass Pellet Bioenergy in the Northeastern USA

    Get PDF
    Grass pellets are a renewable energy supply that combines low technology/small-scale with local production/consumption for a cost effective energy system. There have been significant recent advances in pellet furnace technology and some pellet stove manufacturers now claim their stoves are capable of burning biomass with 5-6% ash content. Cool-season grasses have not been considered acceptable for pelleting and direct combustion in the past due to high ash content. Rain after harvest, however, has been shown to leach significant amounts of potassium and chlorine from grass (Sander, 1997). High yields are possible under lax harvest management (Cherney et al., 2003), producing grass biomass with potassium content as low as 0.5%. Ash content of cool-season grasses is dependent on species, plant maturity, soil type, leaching before and after cutting, loss of high-ash plant parts, and soil contamination. Our objective was to develop a strategy for practical commercial production of relatively low ash cool-season grass biomass

    Evaluation of Narrow-Row Forage Maize in Field-Scale Studies

    Get PDF
    Some dairy producers in the north-eastern USA adopted narrow row (0.38 m) maize forage production in the mid-1990s because of its 5% dry matter (DM) yield advantage (Cox et al., 1998). These dairy producers, however, continued to plant forage maize at high plant densities (125,000 plants/ha) under high N fertility (225 kg N/ha), despite research that indicated that forage maize had optimum DM yields and forage quality when planted at the recommended 100,000 plants/ha under 175 kg/ha of N fertility (Cox & Cherney, 2001). We evaluated forage maize at 0.38 and 0.76 m (conventional) row spacing under recommended vs. high plant densities and N fertility on a large dairy farm in New York. The objective of the study was to demonstrate to dairy producers that narrow-row forage maize does not require high plant densities and N fertility for optimum DM yield and forage quality

    Influence of Grass Species and Sample Preparation on Ensiling Characteristics

    Get PDF
    Laboratory silos are considered a practical method of comparing a number of treatments (O\u27Kiely, 1993). Cherney et al. (2004) reported that vacuum-sealed polyethylene bags effectively ensiled corn silage samples in the laboratory. Grasses, with their inherently higher buffering capacities and lower sugar levels, generally are more difficult to ensile. Objectives were to evaluate the influence of species and chopping (whole vs. shredded) on pH and volatile fatty acid profile of grasses ensiled in vacuum-sealed polyethylene bags and to assess the suitability of this method as a laboratory ensiling method

    Energy gap measurement of nanostructured thin aluminium films for use in single Cooper-pair devices

    Full text link
    Within the context of superconducting gap engineering, Al-\alox-Al tunnel junctions have been used to study the variation in superconducting gap, Δ\Delta, with film thickness. Films of thickness 5, 7, 10 and 30 nm were used to form the small area superconductor-insulator-superconductor (SIS) tunnel junctions. In agreement with previous measurements we have observed an increase in the superconducting energy gap of aluminium with a decrease in film thickness. In addition, we find grain size in small area films with thickness \textbf{\geq} 10 nm has no appreciable effect on energy gap. Finally, we utilize 7 and 30 nm films in a single Cooper-pair transistor, and observe the modification of the finite bias transport processes due to the engineered gap profile

    Map Based WWW Tool for Recommending Forage Species

    Get PDF
    Selecting the “best” forage species or species mixture requires a knowledge and understanding of the consuming animal, soil characteristics, and forage species. The multivariate nature of the problem presents challenges to those interested in solving the practical problem of maximizing available resources. Earlier work at Cornell University resulted in a WWW-based interface that allowed the user to provide a soil type or zip code and additional management factors to initiate the species selection. This approach relies on either user knowledge of soil series or an implied relationship between zip code and soil series that may often be wrong. To improve this management tool, we have developed a working WWW-based map interface that allows the user to move to near field-scale where a “click” will link the map location to underlying soil series information (series id, drainage and slope classes). This information is then passed to the decision support component of the system where the species selection process occurs. This map-based approach takes advantage of the inherent spatial nature of the forage selection problem

    Structure of the C-terminal domain of the arginine repressor protein from Mycobacterium tuberculosis

    Get PDF
    The structure of the core domain of the arginine repressor protein from M. tuberculosis has been determined with (1.85 Å resolution) and without (2.15 Å resolution) the arginine corepressor bound. Three additional arginine molecules have been found to bind to the core domain hexamer at high (0.2 M) arginine concentration

    Intensive Comprehensive Aphasia Programs: An International Survey of Practice

    Get PDF
    Background: In response to the need to simultaneously address multiple domains of the International Classification of Functioning, Disability and Health (ICF) in aphasia therapy and to incorporate intensive treatment doses consistent with principles of neuroplasticity, a potentially potent treatment option termed intensive comprehensive aphasia programs (ICAPs) has been developed. Objective: To conduct an international survey of ICAPs to determine the extent of their use and to explore current ICAP practices. Methods: A 32-item online survey was distributed internationally through Survey Monkey between May and August 2012. The survey addressed ICAP staffing, philosophy, values, funding, admission criteria, activities, family involvement, outcome measures, and factors considered important to success. Results: Twelve ICAPs responded: 8 from the United States, 2 from Canada, and 1 each from Australia and the United Kingdom. The majority of ICAPs are affiliated with university programs and are funded through participant self-pay. ICAPs emphasize individualized treatment goals and evidence-based practices, with a focus on applying the principles of neuroplasticity related to repetition and intensity of treatment. On average, 6 people with aphasia attend each ICAP, for 4 days per week for 4 weeks, receiving about 100 hours of individual, group, and computer-based treatment. Speech-language pathologists, students, and volunteers staff the majority of ICAPs. Conclusions: ICAPs are increasing in number but remain a rare service delivery option. They address the needs of individuals who want access to intensive treatment and are interested in making significant changes to their communication skills and psychosocial well-being in a short period of time. Their efficacy and cost-effectiveness require future investigation

    Quantum theories of (p,q)-forms

    Full text link
    We describe quantum theories for massless (p,q)-forms living on Kaehler spaces. In particular we consider four different types of quantum theories: two types involve gauge symmetries and two types are simpler theories without gauge invariances. The latter can be seen as building blocks of the former. Their equations of motion can be obtained in a natural way by first-quantizing a spinning particle with a U(2)-extended supersymmetry on the worldline. The particle system contains four supersymmetric charges, represented quantum mechanically by the Dolbeault operators and their hermitian conjugates. After studying how the (p,q)-form field theories emerge from the particle system, we investigate their one loop effective actions, identify corresponding heat kernel coefficients, and derive exact duality relations. The dualities are seen to include mismatches related to topological indices and analytic torsions, which are computed as Tr(-1)^F and Tr[(-1)^F F] in the first quantized supersymmetric nonlinear sigma model for a suitable fermion number operator F.Comment: 44 pages, 2 figures, a reference adde
    corecore