Search results for " emission"

Snowpack concentrations and estimated fluxes of volatile organic compounds in a boreal forest

2012

Abstract. Soil provides an important source of volatile organic compounds (VOCs) to atmosphere, but in boreal forests these fluxes and their seasonal variations have not been characterized in detail. Especially wintertime fluxes are almost completely unstudied. In this study, we measured the VOC concentrations inside the snowpack in a boreal Scots pine (Pinus sylvestris L.) forest in southern Finland, using adsorbent tubes and air samplers installed permanently in the snow profile. Based on the VOC concentrations at three heights inside the snowpack, we estimated the fluxes of these gases. We measured 20 VOCs from the snowpack, monoterpenes being the most abundant group with concentrations …

The carbon footprint of a knowledge organization and emission scenarios for a post-COVID-19 world

2021

Publisher Copyright: © 2021 The looming climate crisis requires an immediate response, in which organizations, as major contributors, should play a central role. However, these organizations need appropriate tools to measure and mitigate their climate impacts. One commonly applied method is carbon footprint analysis. Carbon footprint analyses have been conducted for various types of organizations, but knowledge organizations, such as universities and research institutes, have received far less attention, because their carbon footprint is often less visible and can be easily underestimated. This study is based on the carbon footprint analysis of one multinational knowledge organization. This…

Spectroscopic studies of neutron-deficient light nuclei: decay properties of 21Mg, 25Si and 26P

2003

Neutron‐deficient nuclei with Tz equals to −3/2 and −2 have been produced at the GANIL/LISE3 facility in fragmentation reactions of a 95 MeV/u 36Ar primary beam in a 12C target. For the first time, β‐delayed proton and β‐γ emission has been simultaneously observed in the decay of 21Mg, 25Si and 26P. The decay scheme of the latter is proposed and the Gamow‐Teller strength distribution in its β decay is compared to shell‐model calculations based on the USD interaction. The B(GT) values derived from the absolute measurement of the β‐branching ratios are in agreement with the quenching factor of about 60% obtained for allowed Gamow‐Teller transitions in this mass region. A precise half‐life of …

Design and implementation of PET detectors based on monolithic crystals and SiPMs

2018

Esta tesis doctoral se centra tanto en el diseño como en la validación experimental de detectores de rayos gamma para escáneres de tomografía por emisión de positrones (PET, del inglés Positron Emission Tomography). El objetivo principal de esta tesis es el diseño de innovadores bloques detectores PET de alto rendimiento. La técnica PET constituye una de las principales herramientas diagnósticas en medicina nuclear, que es una especialidad médica que utiliza sustancias radiactivas con fines diagnósticos y terapéuticos. Esta técnica de imagen médica permite visualizar procesos fisiológicos y bioquímicos del cuerpo humano in vivo, mediante la administración del elemento radiotrazador. Los rad…

Wind accretion in the massive X-ray binary 4U 2206+54: abnormally slow wind and a moderately eccentric orbit

2006

Massive X-ray binaries are usually classified depending on the properties of the donor star in classical, supergiant and Be X-ray binaries. The massive X-ray binary 4U 2206+54 does not fit in any of these groups, and deserves a detailed study to understand how the transfer of matter and the accretion on to the compact object take place. To this end we study an IUE spectrum of the donor and obtain a wind terminal velocity (v_inf) of ~350 km/s, which is abnormally slow for its spectral type. We also analyse here more than 9 years of available RXTE/ASM data. We study the long-term X-ray variability of the source and find it to be similar to that observed in the wind-fed supergiant system Vela …

Thermomineral waters of Greece: geochemical characterization

2020

Deep-Sea Bioluminescence Blooms after Dense Water Formation at the Ocean Surface

2013

The deep ocean is the largest and least known ecosystem on Earth. It hosts numerous pelagic organisms, most of which are able to emit light. Here we present a unique data set consisting of a 2.5-year long record of light emission by deep-sea pelagic organisms, measured from December 2007 to June 2010 at the ANTARES underwater neutrino telescope in the deep NW Mediterranean Sea, jointly with synchronous hydrological records. This is the longest continuous time-series of deep-sea bioluminescence ever recorded. Our record reveals several weeks long, seasonal bioluminescence blooms with light intensity up to two orders of magnitude higher than background values, which correlate to changes in th…

Accretion in strong field gravity with eXTP

2019

In this paper we describe the potential of the enhanced X-ray Timing and Polarimetry (eXTP) mission for studies related to accretion flows in the strong field gravity regime around both stellar-mass and supermassive black-holes. eXTP has the unique capability of using advanced 'spectral-timing-polarimetry' techniques to analyze the rapid variations with three orthogonal diagnostics of the flow and its geometry, yielding unprecedented insight into the inner accreting regions, the effects of strong field gravity on the material within them and the powerful outflows which are driven by the accretion process.

Thermal induced conformational changes involved in the aggregation of beta-lactoglobulin

2005

Aggregation of proteins appears to be associated most often with conformational and structural changes that lead to exposure of some apolar residues. Depending on the native structure of the protein in exam, aggregation is a process that involves different mechanisms, whose time of occurrence and interplay can depend upon temperature. To single out information about the multistages of the aggregation pathway, here we investigate the thermally induced conformational and structural changes of the beta-lactoglobulin (BLG). The experimental approach consists in studying steady-state fluorescence spectra of intrinsic chromophores, two tryptophans, and Anylino-Naphthalene-Sulfonate dye (ANS) mole…

Binding mode analysis of ABCA7 for the prediction of novel Alzheimer's disease therapeutics

2021

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