2,077 research outputs found
Interannual to Decadal Variability of Atlantic Water in the Nordic and Adjacent Seas
Warm salty Atlantic Water is the main source water for the Arctic Ocean and thus plays an important role in the mass and heat budget of the Arctic. This study explores interannual to decadal variability of Atlantic Water properties in the Nordic Seas area where Atlantic Water enters the Arctic, based on a reexamination of the historical hydrographic record for the years 1950-2009, obtained by combining multiple data sets. The analysis shows a succession of four multi-year warm events where temperature anomalies at 100m depth exceed 0.4oC, and three cold events. Three of the four warm events lasted 3-4 years, while the fourth began in 1999 and persists at least through 2009. This most recent warm event is anomalous in other ways as well, being the strongest, having the broadest geographic extent, being surface-intensified, and occurring under exceptional meteorological conditions. Three of the four warm events were accompanied by elevated salinities consistent with enhanced ocean transport into the Nordic Seas, with the exception of the event spanning July 1989-July 1993. Of the three cold events, two lasted for four years, while the third lasted for nearly 14 years. Two of the three cold events are associated with reduced salinities, but the cold event of the 1960s had elevated salinities. The relationship of these events to meteorological conditions is examined. The results show that local surface heat flux variations act in some cases to reinforce the anomalies, but are too weak to be the sole cause
Phosphorus loss from soil to water.
End of Project ReportThe work described under this project covers field work on
phosphorus(P) loss from soil to water under field conditions. In
addition two International Workshops on P loss to water, held in
Ireland in 1995 and 1998, are also covered under this project. The
results indicate that P loss to water is a complex process and it is
influenced by a number of factors, including hydrology of the soil,
rates and timing of P application and soil P levels. Most work on this
subject indicates that there is a positive relationship between soil test
P levels and P loss to water. There is need for further work to
establish the relative contribution of the different variables involved in
P loss from soil to water for different soils and farming conditions.
This should help provide answers to the most sustainable methods to
minimise losses of P to water and ensure that agricultural production
is compatible with good water quality.European Union Structural Funds (EAGGF
An assessment of the long-term effects of three phosphorus fertiliser regimes on soil phosphorus and sward condition.
End of Project ReportA grazing trial using beef animals (mean weight 260 kg) was used
to determine optimum soil phosphorus levels for dry stock farming.
· The trial commenced in 1968. There were three fertiliser P
treatments, 0, 15 and 30 kg P/ha applied annually. There were
two stocking rates, 3300 and 2400 kg liveweight at turn out,
respectively. Animals were rotationally grazed around six
paddocks per treatment and stocking rates were reduced in June
and September to match feed supply. The trial continued until
1998.
¸ Nitrogen was applied at a rate of 220 kg/ha per year to all
treatments.
¹ Liveweight gains/ha/year were monitored annually. Soil P levels
were monitored by sampling to 10 cm depth.
º The distribution of phosphorus in the soil was recorded by
analysing P levels at various depths from 0-2 mm to 100 cm.
Botanical composition was recorded at the commencement of the
trial and again in 1997. Phosphorus levels in herbage were also
recorded.
» An analysis of the liveweight gain data showed that for optimum
output a Soil Index of 3 (Morgans P between 6.1 and 10.0 mg/l) is
the target Soil P Index.
¼ Phosphorus recovery (as expressed by percentage of P fertiliser
recovered in product) in the P30 treatments was low and was
better in the P15 treatments.
½ The vast bulk of P accumulated near the surface of the soil, but
there was some evidence of movement down the profile in the P30
treatment over a 30 year period. The soil P status influenced both the botanical composition of the
sward and the P content in the herbage. The perennial ryegrass
content declined on the zero P treatment, while there were no
significant differences between the P15 and P30 treatments. The P
concentration in the herbage in the zero P treatments were not
sufficient for healthy growth of plants or animals.E u ropean Union Structural Funding (EAGGF
Определение оптимальных параметров источника рентгеновского излучения на базе малогабаритного ускорителя электронов
Проведено моделирование спектров рентгеновского излучения, генерируемого электронами с энергией 4…10 МэВ в мишенях из различных материалов и разной толщины. Определены оптимальные параметры мишени-конвертора для использования ее в медицинских источниках монохроматического рентгеновского излучения на базе малогабаритных электронных ускорителей. Проведены оценки интенсивности излучения и сравнение источников на базе разных ускорителей
Ex-situ evaluation of PTFE coated metals in a proton exchange membrane fuel cell environment
Metallic-based bipolar plates exhibit several advantages over graphite-based plates, including higher strength, lower manufacturing cost and better electrical conductivity. However, poor corrosion resistance and high interfacial contact resistance (ICR) are major challenges for metallic bipolar plates used in proton exchange membrane (PEM) fuel cells. Corrosion of metallic parts in PEM fuel cells not only increases the interfacial contact resistance but it can also decrease the proton conductivity of the Membrane Electrode Assembly (MEA), due to catalyst poisoning phenomena caused by corrosive products. In this paper, a composite coating of polytetrafluoroethylene (PTFE) was deposited on stainless steel alloys (SS304, SS316L) and Titanium (G-T2) via a CoBlast™ process. Corrosion resistance of the coated and uncoated metals in a simulated PEM fuel cell environment of 0.5 M H2SO4 + 2 ppm HF at 70 °C was evaluated using potentiodynamic polarisation. ICR between the selected metals and carbon paper was measured and used as an indicator of surface conductivity. Scanning Electron Microscopy (SEM), 3D microscopy, Energy Dispersive X-ray (EDX), X-Ray Diffraction (XRD), and contact angle measurements were used to characterise the samples. The results showed that the PTFE coating improved the hydrophobicity and corrosion resistance but increased the ICR of the coated metals due to the unconductive nature of such coating. Thus, it was concluded that it is not fully feasible to use the PTFE alone for coating metals for fuel cell applications and a hybrid coating consisting of PTFE and a conductive material is needed to improve surface conductivity.Enterprise Irelan
RAPPRESENTAZIONE IN CARTA DELLE CARATTERISTICHE DEI SENTIERI AI FINI DELLA MITIGAZIONE DEL RISCHIO GEOMORFOLOGICO
L’ambiente naturale di alcuni particolari ambiti geografici è in rapida evoluzione non solo per quanto
riguarda le sue variabili, legate alle tendenze climatiche in atto, ma anche in relazione all’aumentata
frequentazione turistica. La maggiore diffusione dei mezzi di risalita in montagna e di
navigazione lungo le coste, rende possibile l’accesso anche a siti altrimenti difficilmente raggiungibili:
ciò porta ad un contatto rapido e diretto con ambienti talvolta mutevoli in tempi brevi. La crescente
richiesta di una maggiore conoscenza dell’ambiente naturale, che si esplica per lo più attraverso
la frequentazione della rete sentieristica, implica la necessità di abbinare alle proposte di percorsi
ed itinerari, note illustrative e carte tematiche di immediata lettura, che evidenzino sia i siti di
interesse naturalistico - culturale sia le possibili situazioni di rischio e di difficoltà di percorrenza
degli itinerari stessi. Esistono infatti alcuni elementi morfologici del territorio che di per sé non
costituiscono una pericolosità in senso stretto ma che, a seconda delle capacità del fruitore, possono
essere fonte indiretta di danno, in quanto rendono difficile l’attraversamento di alcuni punti
specifici o la percorrenza di particolari tratti di sentiero. Contemporaneamente la stagionalità in
alcune regioni climatiche e la variabilità meteorologica possono incrementare sia la pericolosità sia
la vulnerabilità e di conseguenza il rischio per il frequentatore. Obiettivo del presente lavoro è quello
di proporre una simbologia adeguata da inserire sulle carte dei sentieri, e più specificatamente
su quelle geoturistiche, per una rapida e facile identificazione di specifiche situazioni riscontrabili
lungo itinerari: questi simboli, che dovranno riferirsi solo alla percorribilità dell’itinerario e non alla
valorizzazione naturalistica dello stesso, andranno rappresentati su base topografica separata, al
fine di non appesantire la lettura dell’elaborato cartografico principale e dovranno fornire solo
informazioni oggettive che saranno poi interpretate dal fruitore dell’itinerario. La simbologia e le
note terranno conto sia delle caratteristiche costanti dei sentieri che degli elementi variabili, in funzione
anche delle condizioni climatiche o stagionali, a seconda dei diversi ambienti interessati
Increasing compliance with wearing a medical device in children with autism
Health professionals often recommend the use of medical devices to assess the health, monitor
the well-being, or improve the quality of life of their patients. Children with autism may present
challenges in these situations as their sensory peculiarities may increase refusals to wear such
devices. To address this issue, we systematically replicated prior research by examining the
effects of differential reinforcement of other behavior (DRO) to increase compliance with
wearing a heart rate monitor in 2 children with autism. The intervention increased compliance to
100% for both participants when an edible reinforcer was delivered every 90 s. The results
indicate that DRO does not require the implementation of extinction to increase compliance with
wearing a medical device. More research is needed to examine whether the reinforcement
schedule can be further thinned
The interactive effects of fertiliser nitrogen with dung and urine on nitrous oxide emissions in grassland
The authors wish to thank the Environmental Protection Agency for funding support under the Environmental Research Technological Development and Innovation programme and the Irish Department of Agriculture, Food and the Marine for
funding support (Grant numbers RSF 13S430 and 11S138).peer-reviewedNitrous oxide (N2O) is an important and potent greenhouse gas (GHG). Although application of nitrogen (N) fertiliser is a feature of many grazing systems, limited data is available on N2O emissions in grassland as a result of the interaction between urine, dung and fertiliser N. A small plot study was conducted to identify the individual and interactive effects of calcium ammonium nitrate (CAN) fertiliser, dung and urine. Application of CAN with dung and urine significantly increased the mass of N2O-N emission. Importantly, the sum of N2O-N emitted from dung and CAN applied individually approximated the emission from dung and CAN fertiliser applied together, that is, an additive effect. However, in the case of urine and CAN applied together, the emission was more than double the sum of the emission from urine and CAN fertiliser applied individually, that is, a multiplicative effect. Nitrous oxide emissions from dung, urine and fertiliser N are typically derived individually and these individual emission estimates are aggregated to produce estimates of N2O emission. The presented findings have important implications for how individual emission factors are aggregated; they suggest that the multiplicative effect of the addition of CAN fertiliser to urine patches needs to be taken into account to refine the estimation of N2O emissions from grazing grasslands.The authors wish to thank the Environmental Protection Agency for funding support under the Environmental Research Technological Development and Innovation programme and the Irish Department of Agriculture, Food and the Marine for funding support (Grant numbers RSF 13S430 and 11S138)
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