7,633 research outputs found
Large-scale numerical modelling of CO2 injection and containment phases for an Italian near-coast reservoir using PFLOTRAN
A potential CO2 storage site located offshore the west coast of Italy, has been modelled using PFLOTRAN assuming an injection rate of 1.5 Mtons/year for 20 years. The model predicts a CO2 footprint characterised by a diameter of about 3.5 km and a maximum pressure build up of 38 bars. The solubility trapping has been quantified, predicting a dissolution in brine of 69% and 79% of the total amount of CO2 injected after 1000 and 2000 years respectively. The residual trapping has also been found to play an important role, with 9% and 6% of the injected CO2 being locked into the hosting matrix pores after 1000 and 2000 years respectively. Considering a worst-case scenario for leakages, where zero critical capillarity pressure has been assumed, minor CO2 leakages through the caprock have been identified, caused by the combined effects of the long-term structural trapping and the large and lasting overpressure caused by the CO2 injection in an ideally closed system. Finally, some preliminary work undertaken as part of an ongoing effort to couple a geochemical model to the multi-phase flow simulations reveals i) small changes in mineral volume fraction and porosity during and after the injection (~5% after 1000 years), and ii) a not negligible self-sealing effect due to precipitation of calcite in the lower layer of the caprock. Further investigations and longer physical time runs are needed to confirm this assumption, but also to gain more confidence on the geochemical model built so far and to estimate the mineral trapping potential for this site. © 2013 The Authors. Published by Elsevier Ltd. Selection and peer-review under responsibility of SINTEF Energi AS
Experimental determination of the frequency and field dependence of Specific Loss Power in Magnetic Fluid Hyperthermia
Magnetic nanoparticles are promising systems for biomedical applications and
in particular for Magnetic Fluid Hyperthermia, a promising therapy that
utilizes the heat released by such systems to damage tumor cells. We present an
experimental study of the physical properties that influences the capability of
heat release, i.e. the Specific Loss Power, SLP, of three biocompatible
ferrofluid samples having a magnetic core of maghemite with different core
diameter d= 10.2, 14.6 and 19.7 nm. The SLP was measured as a function of
frequency f and intensity of the applied alternating magnetic field H, and it
turned out to depend on the core diameter, as expected. The results allowed us
to highlight experimentally that the physical mechanism responsible for the
heating is size-dependent and to establish, at applied constant frequency, the
phenomenological functional relationship SLP=cH^x, with 2<x<3 for all samples.
The x-value depends on sample size and field frequency/ intensity, here chosen
in the typical range of operating magnetic hyperthermia devices. For the
smallest sample, the effective relaxation time Teff=19.5 ns obtained from SLP
data is in agreement with the value estimated from magnetization data, thus
confirming the validity of the Linear Response Theory model for this system at
properly chosen field intensity and frequency
Economic benefit and social impact derived by a food loss prevention strategy in the vegetable sector: A spatial and temporal analysis at the regional level
Introduction: Reduction of food loss in the horticultural sector is critical to simultaneously support the transition toward a diet with higher consumption of vegetables and the achievement of policy goals aimed at halving the quantity of wastage by 2030. However, the lack of precise information and the presence of múltiple interconnected factors makes it difficult to assess the potential socioeconòmic benefits and therefore the decision-making process of food loss reduction strategies. Methods: A case study approach has been used to assess the econòmic loss and nutrional impact of food loss in the horticulture primary production. The selection of the main vegetable products was based on an historical series while econòmic and nutritional impact were estimated starting from national and European indicator. Results: The food loss correspond to 26% of the total production and 14% of the total agricultural production econòmic value. The social analysis confirm the possibility of redistributing food loss among the population even in the most critical months and areas. Discussion: The combination of social and econòmic indicator resulted essential to provide key information at the decision-making level to pave the way for the elaboration of short- and long-term food loss reduction strategies. Indeed, no single-bullet strategy can be applied to overcome the problem of food loss as many actor with different needs are involved
Reação de genótipos de milho e sorgo a Meloidogyne incognita, M. javanica e Pratylenchus brachyurus.
Colloidal Assemblies of Oriented Maghemite Nanocrystals and their NMR Relaxometric Properties
Elevated-temperature polyol-based colloidal-chemistry approach allows for the
development of size-tunable (50 and 86 nm) assemblies of maghemite iso-oriented
nanocrystals, with enhanced magnetization. 1H-Nuclear Magnetic Resonance (NMR)
relaxometric experiments show that the ferrimagnetic cluster-like colloidal
entities exhibit a remarkable enhancement (4 to 5 times) in the transverse
relaxivity, if compared to that of the superparamagnetic contrast agent
Endorem, over an extended frequency range (1-60 MHz). The marked increase of
the transverse relaxivity r2 at a clinical magnetic field strength (1.41 T),
which is 405.1 and 508.3 mM-1 s-1 for small and large assemblies respectively,
allows to relate the observed response to the raised intra-aggregate magnetic
material volume fraction. Furthermore, cell tests with murine fibroblast
culture medium confirmed the cell viability in presence of the clusters. We
discuss the NMR dispersion profiles on the basis of relaxivity models to
highlight the magneto-structural characteristics of the materials for improved
T2-weighted magnetic resonance images.Comment: Includes supporting informatio
Cold streams of ionospheric oxygen in the plasma sheet during the CDAW-6 event of March 22, 1979
During magnetospheric substorm events, the plasma and ion composition experiments in the ISEE-1 and 2 satellites detected cold ionospheric O+ streams, moving tailwards in the near Earth magnetotail. Flow is parallel to the magnetic field lines, with drift velocity in agreement with the electric field topology obtained by mapping the model ionospheric field along the magnetic field lines. Fluctuations of the flow velocity of the streams can be related to magnetotail movements. Oscillations of the flow direction and speed with periods ranging from 5 to 10 min that suggest the presence of waves are observed. The streams are observed at all distances between 15 and 6 Re from the Earth. When averaged over 360 deg, the streams show up as a low energy peak, superimposed on the distribution of isotropic plasma sheet ions. This double-peak structure of the energy spectrum seems typical of the disturbed plasma sheet
Utilisation de poudres fluorescentes pour l'analyse des déplacements des petits rongeurs dans la nature
GPS-based CERN-LNGS time link for Borexino
We describe the design, the equipment, and the calibration of a new GPS based
time link between CERN and the Borexino experiment at the Gran Sasso Laboratory
in Italy. This system has been installed and operated in Borexino since March
2012, and used for a precise measurement of CNGS muon neutrinos speed in May
2012. The result of the measurement will be reported in a different letter.Comment: 13 pages, 11 figure
Raising Capital Overseas
The article states that more and more companies are trying to raise capital by listing their securities for sale on foreign exchanges.More and more companies are trying to raise capital by listing their securities for sale on foreign exchanges. However, the way financial statements are prepared varies from one country to the next. U.S. companies looking to raise capital abroad must consider the myriad rules regarding financial statement presentation just as foreign companies listing stock in the United States must adhere to the rules and regulations of the Securities and Exchange Commission. Similarly, the costs of reconciling U.S. accounting standards to adhere to foreign standards also can be high, so it is important that U.S. companies know the questions they will face when going global. Although the details of additional disclosures must be determined case by case, they can be developed in the context of normal corporate reporting. However, U.S. public companies should determine the nature and extent of additional disclosures in advance to provide for an orderly approach to corporate reporting and to avoid any undue delay in the listing process
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