Search results for "F.U.E."

Numerical Procedures and their Practical Application in PV Module Analyses. Part IV: Atmospheric Transparency Parameters - Application

2020

Abstract The presented article relates to aspects of PV module testing using natural sunlight in outdoor conditions. It is a continuation of the article Part III: parameters of atmospheric transparency - determining and correlations. This article discusses the practical application of the indexes: atmosphere purity - k Tm , diffused component content - k s/o , beam clear sky index - K b - in testing various modules in outdoor conditions. Their influence on the conversion of modules made from various absorbers and various technologies is demonstrated. Their practical application in module testing in outdoor conditions is described and it - has been demonstrated that the results of the analys…

Geographic and temporal variations in turbulent heat loss from lakes : A global analysis across 45 lakes

2018

Heat fluxes at the lake surface play an integral part in determining the energy budget and thermal structure in lakes, including regulating how lakes respond to climate change. We explore patterns in turbulent heat fluxes, which vary across temporal and spatial scales, using in situ high-frequency monitoring data from 45 glob- ally distributed lakes. Our analysis demonstrates that some of the lakes studied follow a marked seasonal cycle in their turbulent surface fluxes and that turbulent heat loss is highest in larger lakes and those situated at low latitude. The Bowen ratio, which is the ratio of mean sensible to mean latent heat fluxes, is smaller at low lati- tudes and, in turn, the rel…

Strombolian eruptions and dynamics of magma degassing at Yasur Volcano (Vanuatu)

2020

Abstract Open vent basaltic volcanoes account for a substantial portion of the global atmospheric outgassing flux, largely through passive degassing and mild explosive activity. We present volcanic gas flux and composition data from Yasur Volcano, Vanuatu collected in July 2018. The average volcanic plume chemistry is characterised by a mean molar CO2/SO2 ratio of 2.14, H2O/SO2 of 148 and SO2/HCl of 1.02. The measured mean SO2 flux in the period of 6th to 9th July is 4.9 kg s−1. Therefore, the mean fluxes of the other species are 7.5 kg∙s−1 CO2, 208 kg∙s−1 H2O and 4.8 kg∙s−1 HCl. The degassing regime at Yasur volcano ranges from ‘passive’ to ‘active’ styles, with the latter including Stromb…

Application of entropic approach to estimate the mean flow velocity and Manning roughness coefficient in a high-curvature flume

2016

The entropy-based approach allows the estimation of the mean flow velocity in open channel flow by using the maximum flow velocity. The linear relationship between the mean velocity, umax, and the mean flow velocity, um, through the dimensionless parameter Φ(M), has been verified both in natural rivers and in laboratory channels. Recently, the authors of this study investigated the reliability of the entropy-based formula in a straight channel and under different bed and side-walls' roughness conditions. The present study aims to further validate the entropy-based approach and to explore the effectiveness of entropy-based formula in high curvature channels. Results show that as the effect o…

Comment on “Rill erosion processes on steep colluvial deposit slope under heavy rainfall in flume experiments with artificial rain by F. Jiang et al.”

2020

Abstract Since rill flows are characterized by small water depths and steeply sloping channels, the corresponding hydraulic conditions are very different to those which are typically found in channels of streams and rivers. Furthermore, limited information is currently available on the effect of rainfall on flow resistance. The objective of this comment was to investigate the applicability of a recently theoretically deduced rill flow resistance equation, based on a power-velocity profile, using measurements carried out by Jiang et al. for both different slope steepness conditions and rainfall intensity. The relationship between the velocity profile parameter Γ, the channel slope and the fl…

Petrographic and geochemical characterization of the Middle‒Upper Jurassic Fe–Mn crusts and mineralizations from Monte Inici (north-western Sicily): …

2021

AbstractFe–Mn concretions and mineralizations, associated with condensed horizons and hardground, are significant archives in ancient carbonate rocks. Their petro-chemical study allows an assessment of the palaeoenvironmental context in which they were formed also connected to their biotic or abiotic origin. At the western side of the Monte Inici (Fornazzo section, north-western Sicily) a well exposed outcrop of condensed pelagic limestones (Rosso Ammonitico facies: Middle‒Upper Jurassic) is well-known and thoroughly studied. In this section, the base of the Rosso Ammonitico facies consists of a very condensed level rich in fossils with a variable thickness deposited from the early Bathonia…

Changes in SO2 Flux Regime at Mt. Etna Captured by Automatically Processed Ultraviolet Camera Data

2019

We used a one-year long SO2 flux record, which was obtained using a novel algorithm for real-time automatic processing of ultraviolet (UV) camera data, to characterize changes in degassing dynamics at the Mt. Etna volcano in 2016. These SO2 flux records, when combined with independent thermal and seismic evidence, allowed for capturing switches in activity from paroxysmal explosive eruptions to quiescent degassing. We found SO2 fluxes 1.5−2 times higher than the 2016 average (1588 tons/day) during the Etna’s May 16−25 eruptive paroxysmal activity, and mild but detectable SO2 flux increases more than one month before its onset. The SO2 flux typically peaked during a lava fo…

Prodigious emission rates and magma degassing budget of major, trace and radioactive volatile species from Ambrym basaltic volcano, Vanuatu island Arc

2016

Abstract Ambrym volcano, in the Vanuatu arc, is one of the most active volcanoes of the Southwest Pacific region, where persistent lava lake and/or Strombolian activity sustains voluminous gas plume emissions. Here we report on the first comprehensive budget for the discharge of major, minor, trace and radioactive volatile species from Ambrym volcano, as well as the first data for volatiles dissolved in its basaltic magma (olivine-hosted melt inclusions). In situ MultiGAS analysis of H 2 O, CO 2 , SO 2 and H 2 S in crater rim emissions, coupled with filter-pack determination of SO 2 , halogens, stable and radioactive metals demonstrates a common magmatic source for volcanic gases emitted by…

2016

Gianluca Tramontana was supported by the GEOCARBON EU FP7 project (GA 283080). Dario Papale, Martin Jung and Markus Reichstein acknowledge funding from the EU FP7 project GEOCARBON (grant agreement no. 283080) and the EU H2020 BACI project (grant agreement no. 640176). Gustau Camps-Valls wants to acknowledge the support by an ERC Consolidator Grant with grant agreement 647423 (SEDAL). Kazuhito Ichii was supported by Environment Research and Technology Development Funds (2-1401) from the Ministry of the Environment of Japan and the JAXA Global Change Observation Mission (GCOM) project (no. 115). Christopher R. Schwalm was supported by National Aeronautics and Space Administration (NASA) gran…

Simulación de flujos de carbono terrestres mediante teledetección y modelización de ecosistemas

2019

[EN] The main goal of this thesis is the establishment of a framework to analyze the forest ecosystems in peninsular Spain in terms of their role in the carbon cycle. In particular, the carbon fluxes that they exchange with atmosphere are modeled to evaluate their potential as carbon sinks and biomass reservoirs. The assessment of gross and net carbon fluxes is performed at 1-km spatial scale and on a daily basis using two different ecosystem models, Monteith and BIOME-BGC, respectively. These models are driven by a combination of satellite and ground data, part of the latter being also employed as a complementary data source and in the validation process. [ES] El objetivo principal de esta…