Search results for " Emission"
showing 10 items of 1496 documents
Inter-crystal scatter in positron emission tomography: Identification techniques and effects on reconstructed images for AX-PET demonstrator
2012
La PET es una técnica de imagen en medicina nuclear que permite la visualización in-vivo y en 3D de procesos funcionales en seres vivos. Un escáner PET mide los rayos gamma producidos al aniquilarse un positrón, el cual es emitido por un radioisótopo inyectado al paciente. La eficiencia del sistema es una característica crucial de los escáneres PET de alta resolución dedicados a la imagen del cerebro o de animales pequeños con el fin de obtener una imagen más fiel o de reducir la actividad del radiotrazador, y por consiguiente, la dosis inyectada al paciente. El objetivo de este trabajo de investigación es mejorar la eficiencia y calidad de imagen de un prototipo de escáner PET axial (AX-PE…
Consequential life cycle assessment of the Italian power system
2022
Energy production and consumption contribute to 76% of the European greenhouse gas (GHG) emissions in 2018, and 90% of global GHG emissions with land use, land use change and forestation (LULUCF) in the same year. By applying energy efficiency (EE) and renewable energy (RE) technologies, the GHG emission intensity of the energy sector reduced by 1.3% in 2018 compared to the previous year. The current climate change policy aims at decarbonization, sustainable environment, economic prosperity and social equity. It requires the deep decarbonisation of the economies, meaning that the energy and power systems as well as other emission intensive sectors need to transform into zero-emission ones. …
Proton dripline studies at ISOLDE: 31Ar and 9C
2002
In this contribution examples of the application of new technologies to disentangle the mechanism of beta-delayed multiparticle emission are given. In particular the mechanism of β-delayed two-proton emission from 31Ar has be resolved and proved to be sequential, a preview of 9C-decay data is discussed. peerReviewed
Characteristics of segmented super clover detector in close geometry decay measurements
2001
Characteristics of the segmented Super Clover germanium detector response in close geometries have been studied. Results obtained with localising hit pattern recognition are compared with results from add-back and individual crystal analysis. The detector has been used at the focal plane of a gas filled recoil separator to detect isomeric gamma-rays from the nuclei produced in the 150Sm(42Ca,4n)188Pb reaction. Coincidence data from the detector was analysed and the level scheme below the 1.2 μ s isomeric state in 188Pb could be deduced. peerReviewed
Energy level determination of purine containing blue light emitting organic compounds
2018
Organic light emitting diodes (OLED) have found their applications in the mobile and TV screens. Till now the commercially available diodes are made by expensive thermal evaporation in a vacuum. The costs of OLED fabrication could be decreased by applying low-cost wet casting methods, for example, spin-coating. In this work, we have studied a group of blue light emitting purine derivatives which could potentially be used in OLEDs. The advantage of these compounds is their ability to form amorphous thin films from solutions. All the thin films were prepared by the spincoating method from chloroform solution on ITO glass. The position of hole and electron transport energy levels is important …
Combined Spectroscopic and TD-DFT Analysis to Elucidate Substituent and Acidochromic Effects in Organic Dyes: A Case Study on Amino- versus Nitro-Sub…
2020
Made available in DSpace on 2020-12-12T01:33:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01 A combined spectroscopic and TD-DFT case study was performed, to identify a robust method to calculate the complex near UV/Vis absorption spectra of various amino- vs. nitro-substituted 2,4-diphenylquinolines, which vary strongly under neutral and successively acidic conditions. For this, different DFT functionals were tested for geometry optimization and the TD part to calculate the neutral and different protonated species in a fast screening approach, i. e. using single point calculations in an implicit solvent. Offset-corrected M06HF, hitherto only applied to polymers, was identif…
Radiolabeling of Nanoparticles and Polymers for PET Imaging
2014
Nanomedicine has become an emerging field in imaging and therapy of malignancies. Nanodimensional drug delivery systems have already been used in the clinic, as carriers for sensitive chemotherapeutics or highly toxic substances. In addition, those nanodimensional structures are further able to carry and deliver radionuclides. In the development process, non-invasive imaging by means of positron emission tomography (PET) represents an ideal tool for investigations of pharmacological profiles and to find the optimal nanodimensional architecture of the aimed-at drug delivery system. Furthermore, in a personalized therapy approach, molecular imaging modalities are essential for patient screeni…
Chemical and isotopic characterization of rainwater in volcanic, urban and industrial areas of Sicily (Italy)
2021
The chemical composition of rainwater depends on (i) the dissolution of gases and particulate matter emitted by different sources, (ii) the chemical and physical reactions occurring during local and regional scale transport, and (iii) removal processes. The source of major and trace elements dissolved in rainwater can be both natural (e.g. sea salts, volcanic emissions, geogenic dust, biogenic material) and anthropogenic (e.g. industrial plants, vehicular traffic, domestic heating, vessel traffic). A group of trace elements has been recently brought to attention, especially for their possible environmental impacts, the Technology-critical elements (TCEs): Ga, Ge, In, Te, Nb, Ta, Tl, the Pla…
Husk Energy Supply Systems for Sunflower Oil Mills
2020
Together with solar, wind, and hydro renewable energy sources (RES), biomass constitutes an integral part of the high-renewables electricity systems. Considerable feedstocks for electricity generation are process-based residues. Ukraine is the world leader in sunflower seed production, therefore, husk (a by-product of oil production) is a promising biofuel for combustion- based power plants. The plants consume primarily electricity and fossil fuels (natural gas or fuel oil) for steam production. Their usage affects the edible oil production cost and impacts on climate change. The above facts force us to look for alternatives. By-product (husk) utilization can reduce exhaustible energy consu…
A methodology for the control of the residual lifetimes of carbon fibre reinforced composite pressure vessels
2005
International audience; Pressure vessels must be periodically proof tested. Traditional techniques for metal vessels are inapplicable for composite vessels as the latter do not break by crack propagation so that the reasoning behind the traditional testing procedures is not appropriate. Damage accumulation leading to the degradation of a composite vessel is by fibre failure. Fibres show a wide distribution in strengths and loading a composite inevitably breaks some. The method which has been developed is supported by an analysis of delayed fibre failure due to the relaxation of the resin around fibre breaks. This provokes overloading of intact fibres neighbouring breaks. The time until a cr…