990 research outputs found
Analysis of the energy performance of a ground source heat pump system after five years of operation
[EN] GeoCool plant was the result of a EU project whose main purpose was to adapt ground coupled heat pump
technology to coolingdominatedareas. The executionofthis experimentalplant was completedatthe end
of year 2004, starting on February 2005 the regular operation of the air conditioning system. Since then,
GeoCool facility has been monitored by a network of sensors characterizing its most relevant parameters.
Several aspects of the performance and behaviour of the system during its first operational year were
presented on a previous paper. This paper presents the energy performance measurements of GeoCool
ground coupled heat pump system acquired during five years of operation as well as the evolution of the
return water temperature from the ground as a representative of the ground temperature. The analysis
of the experimental results shows that the system energy performance is maintained through the years
with no appreciable impact on ground thermal responseThis work has been supported by FP7 project "Advanced ground source heat pump systems for heating and cooling in Mediterranean climate" (GROUND-MED).Montagud Montalvá, CI.; Corberán Salvador, JM.; Montero Reguera, ÁE.; Urchueguía Schölzel, JF. (2011). Analysis of the energy performance of a ground source heat pump system after five years of operation. Energy and Buildings. 43(12):3618-3626. https://doi.org/10.1016/j.enbuild.2011.09.036S36183626431
A comparative study of the electrochemical properties of vitamin B-6 related compounds at physiological pH
A comparative study of vitamin B6 group and related compounds in buffered solutions using electrochemical techniques has been performed at neutral pH. Irreversible bi- or tetra-electronic processes are observed for these substances, and the electron transfer coefficient (αn) calculated. It was concluded that either the first or second electron transfer were the rate determining step of the electrode process. The diffusion coefficient of these substances was calculated and the values given follow an inverse tendency to the molecular size. For aldehydes the values obtained were corrected of the hydration reaction.
It is important to remark that catalytic waves were reported for the first time for these compounds. Using a model involving the nitrogen of the basic structure the kinetic constants were calculated for most of them
Life cycle modelling of environmental impacts of application of processed organic municipal solid waste on agricultural land (EASEWASTE)
A model capable of quantifying the potential environmental impacts of agricultural application of composted or anaerobically digested source-separated organic municipal solid waste (MSW) is presented. In addition to the direct impacts, the model accounts for savings by avoiding the production and use of commercial fertilizers. The model is part of a larger model, Environmental Assessment of Solid Waste Systems and Technology (EASEWASTE), developed as a decisionsupport model, focusing on assessment of alternative waste management options. The environmental impacts of the land application of processed organic waste are quantified by emission coefficients referring to the composition of the processed waste and related to specific crop rotation as well as soil type. The model contains several default parameters based on literature data, field experiments and modelling by the agro-ecosystem model, Daisy. All data can be modified by the user allowing application of the model to other situations. A case study including four scenarios was performed to illustrate the use of the model. One tonne of nitrogen in composted and anaerobically digested MSW was applied as fertilizer to loamy and sandy soil at a plant farm in western Denmark. Application of the processed organic waste mainly affected the environmental impact categories global warming (0.4–0.7 PE), acidification (–0.06 (saving)–1.6 PE), nutrient enrichment (–1.0 (saving)–3.1 PE), and toxicity. The main contributors to these categories were nitrous oxide formation (global warming), ammonia volatilization (acidification and nutrient enrichment), nitrate losses (nutrient enrichment and groundwater contamination), and heavy metal input to soil (toxicity potentials). The local agricultural conditions as well as the composition of the processed MSW showed large influence on the environmental impacts. A range of benefits, mainly related to improved soil quality from long-term application of the processed organic waste, could not be generally quantified with respect to the chosen life cycle assessment impact categories and were therefore not included in the model. These effects should be considered in conjunction with the results of the life cycle assessment
In situ optimization methodology for the water circulation pumps frequency of ground source heat pump systems
[EN] This paper presents an experimental study of the influence of the water circulation pumps frequency atthe indoor and outdoor loops in the overall system performance of a ground source heat pump moni-tored plant, and describes a three steps new methodology to optimize the system energy performanceand obtain the values of the optimal frequencies when ON/OFF regulation is employed. The first stepconsists of several experimental tests of pseudo-random sequence of frequency steps for both, internaland external circulation pumps, carried out during a single day. The second step is the characterization ofthe quasi-steady state system performance as a function of circulation pumps frequencies. The final stepconsists of, by means of an analytical expression, the extrapolation of results to any partial load ratio,what allows finding the optimal frequency as a function of the instantaneous thermal load. The advantageof the proposed methodology is that it can be carried out on site and is able to consider the phenomenaoccurring at the heat pump and the ground source heat exchanger when the flow rates are varied. Themethodology can be applied to any installation incorporating variable speed circulation pumps. Resultsindicate large energy savings potential for this kind of installation.This work was supported by the European Commission under the FP7 framework project GROUND-MED: "Advanced ground source heat pump systems for heating and cooling in Mediterranean climate".Montagud Montalvá, CI.; Corberán Salvador, JM.; Montero Reguera, ÁE. (2014). In situ optimization methodology for the water circulation pumps frequency of ground source heat pump systems. Energy and Buildings. 68, A:42-53. https://doi.org/10.1016/j.enbuild.2013.09.030S425368,
A 'civilized' drink and a 'civilizing' industry: wine growing and cultural imagining in colonial New South Wales
My starting point for this thesis was the absence of a foundation history of Australian wine growing conducted by an historian rather than researchers in other disciplines or the media. I have used existing work on wine history in New South Wales from 1788 to 1901 alongside a significant body of new research to create an historical argument suitable for incorporation into more broadly-themed narratives of Australian history and to inform studies of wine growing in other academic fields. My main argument is that although wine growing proved of little economic value in colonial primary production compared with nation-building commodities - such as pastoralism, wheat growing and gold - advocates of the cultivation of wine grapes believed wine growing embodied beneficial, even transformative, cultural value so they persisted in attempting to create a ‘civilizing’ industry producing a ‘civilized’ drink despite lacklustre consumption of their product and very modest profits. Several times, from 1788 to 1901, these advocates spoke out or wrote about wine and wine growing as capable of creating order in a wild or ‘savage’ landscape and within a settler society shaped culturally by shifting adaptations to both imported and ‘native’ influences in agriculture as well as alcohol production, consumption and distribution. While the methodological framework employed here falls mainly within cultural and economic history, sociological theories have contributed to findings on causation. The result is a comprehensive narrative of colonial wine growing in New South Wales enriched by links to key developments in Australian colonial history and with reference to wine growing in other British colonies or former territories
A novel HIV vaccine adjuvanted by IC31 induces robust and persistent humoral and cellular immunity.
The HIV vaccine strategy that, to date, generated immune protection consisted of a prime-boost regimen using a canarypox vector and an HIV envelope protein with alum, as shown in the RV144 trial. Since the efficacy was weak, and previous HIV vaccine trials designed to generate antibody responses failed, we hypothesized that generation of T cell responses would result in improved protection. Thus, we tested the immunogenicity of a similar envelope-based vaccine using a mouse model, with two modifications: a clade C CN54gp140 HIV envelope protein was adjuvanted by the TLR9 agonist IC31®, and the viral vector was the vaccinia strain NYVAC-CN54 expressing HIV envelope gp120. The use of IC31® facilitated immunoglobulin isotype switching, leading to the production of Env-specific IgG2a, as compared to protein with alum alone. Boosting with NYVAC-CN54 resulted in the generation of more robust Th1 T cell responses. Moreover, gp140 prime with IC31® and alum followed by NYVAC-CN54 boost resulted in the formation and persistence of central and effector memory populations in the spleen and an effector memory population in the gut. Our data suggest that this regimen is promising and could improve the protection rate by eliciting strong and long-lasting humoral and cellular immune responses
On the gravitational, dilatonic and axionic radiative damping of cosmic strings
We study the radiation reaction on cosmic strings due to the emission of
dilatonic, gravitational and axionic waves. After verifying the (on average)
conservative nature of the time-symmetric self-interactions, we concentrate on
the finite radiation damping force associated with the half-retarded minus
half-advanced ``reactive'' fields. We revisit a recent proposal of using a
``local back reaction approximation'' for the reactive fields. Using
dimensional continuation as convenient technical tool, we find, contrary to
previous claims, that this proposal leads to antidamping in the case of the
axionic field, and to zero (integrated) damping in the case of the
gravitational field. One gets normal positive damping only in the case of the
dilatonic field. We propose to use a suitably modified version of the local
dilatonic radiation reaction as a substitute for the exact (non-local)
gravitational radiation reaction. The incorporation of such a local
approximation to gravitational radiation reaction should allow one to complete,
in a computationally non-intensive way, string network simulations and to give
better estimates of the amount and spectrum of gravitational radiation emitted
by a cosmologically evolving network of massive strings.Comment: 48 pages, RevTex, epsfig, 1 figure; clarification of the domain of
validity of the perturbative derivation of the string equations of motion,
and of their renormalizabilit
Development and validation of an electroanalytical methodology for determination of isoniazid and rifampicin content in pharmaceutical formulations
Kepler-22b: A 2.4 Earth-radius Planet in the Habitable Zone of a Sun-like Star
A search of the time-series photometry from NASA's Kepler spacecraft reveals
a transiting planet candidate orbiting the 11th magnitude G5 dwarf KIC 10593626
with a period of 290 days. The characteristics of the host star are well
constrained by high-resolution spectroscopy combined with an asteroseismic
analysis of the Kepler photometry, leading to an estimated mass and radius of
0.970 +/- 0.060 MSun and 0.979 +/- 0.020 RSun. The depth of 492 +/- 10ppm for
the three observed transits yields a radius of 2.38 +/- 0.13 REarth for the
planet. The system passes a battery of tests for false positives, including
reconnaissance spectroscopy, high-resolution imaging, and centroid motion. A
full BLENDER analysis provides further validation of the planet interpretation
by showing that contamination of the target by an eclipsing system would rarely
mimic the observed shape of the transits. The final validation of the planet is
provided by 16 radial velocities obtained with HIRES on Keck 1 over a one year
span. Although the velocities do not lead to a reliable orbit and mass
determination, they are able to constrain the mass to a 3{\sigma} upper limit
of 124 MEarth, safely in the regime of planetary masses, thus earning the
designation Kepler-22b. The radiative equilibrium temperature is 262K for a
planet in Kepler-22b's orbit. Although there is no evidence that Kepler-22b is
a rocky planet, it is the first confirmed planet with a measured radius to
orbit in the Habitable Zone of any star other than the Sun.Comment: Accepted to Ap
Interpreting Quantum Particles as Conceptual Entities
We elaborate an interpretation of quantum physics founded on the hypothesis
that quantum particles are conceptual entities playing the role of
communication vehicles between material entities composed of ordinary matter
which function as memory structures for these quantum particles. We show in
which way this new interpretation gives rise to a natural explanation for the
quantum effects of interference and entanglement by analyzing how interference
and entanglement emerge for the case of human concepts. We put forward a scheme
to derive a metric based on similarity as a predecessor for the structure of
'space, time, momentum, energy' and 'quantum particles interacting with
ordinary matter' underlying standard quantum physics, within the new
interpretation, and making use of aspects of traditional quantum axiomatics.
More specifically, we analyze how the effect of non-locality arises as a
consequence of the confrontation of such an emerging metric type of structure
and the remaining presence of the basic conceptual structure on the fundamental
level, with the potential of being revealed in specific situations.Comment: 19 pages, 1 figur
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