Search results for "Breed"

Preliminary thermal optimization and investigation of the overall structural behaviour of the EU-DEMO water-cooled lead lithium left outboard blanket…

2022

The conceptual design phase of the EU-DEMO reactor has been recently launched, with the aim of evolving the DEMO pre-conceptual layout towards a more robust and articulated geometric configuration able to cope with most of the design requirements and to show further margins for the passing of the current potential show-stoppers. Hence, the achievement of the conceptual design of the Water-Cooled Lead Lithium Breeding Blanket (WCLL BB) is one of the milestones the EUROfusion consortium aims to achieve in the close future. To this purpose, within the framework of the research activities promoted by EUROfusion, a research campaign has been launched at the University of Palermo, in close cooper…

Experimental tests on Li-ceramic breeders for the helium cooled pebble bed (HCPB) blanket design

2003

The Helium Cooled Pebble Bed (HCPB) Test Blanket Module (TBM) to be tested in ITER (International Thermonuclear Experimental Reactor) Reactor foresees the utilization of Lithiate ceramics as Tritium breeder in form of pebble beds. Since 1998, ENEA has launched many experimental activities for the evaluation of the breeder thermomechanics and the interaction between the pebble beds and the prismatic steel containment walls. Main objectives of these activities are the measurement of the pebble bed effective thermal conductivity, the wall heat transfer coefficient, the pressure loads and deformations on the lateral walls and their dependency from the mechanical constraints. The paper presents …

Development of helium coolant DEMO first wall model for SYCOMORE system code based on HCLL concept

2018

Abstract The conceptual design of the demonstration fusion power reactor, known as DEMO, is ongoing and several reactor configurations have to be investigated by exploring different design parameters. For these reasons, within the European framework, systems codes like SYCOMORE (SYstem COde for MOdelling tokamak REactor) have been developed. SYCOMORE includes several specific modules, one of which is aimed to define a suitable design of the helium breeding blanket. The research activity has been devoted to improve the method to define automatically the First Wall design starting from thermal-hydraulic and thermo-mechanical considerations, using analytical design formulae and, also, taking i…

Progress of the conceptual design of the European DEMO breeding blanket, tritium extraction and coolant purification systems

2020

Abstract In the frame of the EUROfusion consortium activities the Helium Cooled Pebble Bed (HCPB) and the Water Cooled Lithium Lead (WCLL) concepts are being developed as possible candidates to become driver Breeding Blanket (BB) for the EU DEMO, which aims at the tritium self-sufficiency and net electricity production. The two BB design options encompass water or helium as coolants and solid ceramic with beryllium/beryllides or PbLi as tritium breeder and neutron multipliers. The BB segments have evolved towards a more stable conceptual design taking into account multiple feasibility aspects and requirements imposed by interfacing systems. Possible solutions to improve shielding capabiliti…

On the numerical assessment of the thermo-mechanical performances of the DEMO Helium-Cooled Pebble Bed breeding blanket module

2014

Within the framework of the European DEMO Breeder Blanket Programme, a research campaign has been launched by University of Palermo, ENEA-Brasimone and Karlsruhe Institute of Technology to theoretically investigate the thermo-mechanical behavior of the Helium-Cooled Pebble Bed (HCPB) breeding blanket module of the DEMO1 blanket vertical segment, under normal operation and over-pressurization loading scenarios. The research campaign has been carried out following a theoretical-computational approach based on the finite element method (FEM) and adopting a qualified commercial FEM code. A realistic 3D FEM model of the HCPB blanket module central poloidal-radial region has been developed, inclu…

Using the Breeder genetic algorithm to optimize a multiple regression analysis model used in prediction of the mesiodistal width of unerupted teeth

2014

For the prediction of the unerupted canine and premolars mesiodistal size, have been proposed different variants of multiple linear regression equations (MLRE). These are based on the amount of the upper and lower permanent incisors with a tooth of the lateral support. Aim of present study was to develop a method for optimization of MLRE, using a genetic algorithm for determining a set of coefficients that minimizes the prediction error for the sum of permanent premolars and canines dimensions from a group of young people in an area Romania's central city represented by Sibiu. To test the proposed method, we used a multiple linear regression equation derived from the estimation method propo…

Gli uccelli delle isole circumsiciliane

2015

Gli autori sintetizzano tutte le informazioni bibliografiche e inedite sulle specie che sino al 30 agosto 2015 sono state contattate almeno una volta nelle 14 isole circumsiciliane (Eolie, Ustica, Egadi, Pantelleria e Pelagie), confrontando alla fine la lista complessiva con quella delle isole Maltesi. In totale sono ad oggi note 434 specie (isole Maltesi incluse); molte di esse hanno mostrato nel corso dei secoli una notevole capacità di colonizzazione, fluttuando nel tempo o addirittura estinguendosi e ricolonizzando alcune isole. Questi piccoli territori in mezzo al mare rappresentano ottimi siti di controllo dell’andamento delle migrazioni nel corso dei decenni; alcune specie hanno chia…

STUDY OF FATTY ACIDS PROFILE IN OVINE AND CAPRINE SICILIAN DAIRY BREED AND ASSOCIATION WITH POSSIBLE CANDIDATE GENES

In Sicilia, le razze bovine, ovine e caprine e le produzioni lattiero-casearie rappresentano una risorsa importante per l’economia del settore zootecnico. L’importanza economica del latte ovino e caprino è soprattutto legata per il primo alla sua trasformazione in prodotti lattiero-caseari, per il secondo al possibile utilisso per il consumo fresco. Per entrambe queste specie, il contenuto di grasso e proteine è importante tanto quanto la produzione di latte. L’individuazione dei geni responsabili delle caratteristiche quanti-qualitative del latte dei piccoli ruminanti permetterebbe quindi di aumentare l’efficienza del miglioramento genetico e di considerare nuovi obiettivi di selezione com…

Genetic parameters for early lamb survival and growth in Scottish Blackface sheep1

2008

The objectives of this study were 1) to estimate the heritability of lamb survival and growth in the Scottish Blackface breed; 2) to examine the relationship between lamb survival and live BW; and 3) to investigate the possibility of using lamb survival in a breeding program for this breed. The data used for the analyses contained information about survival and live BW at different ages on 4,459 animals. The records were collected from 1988 to 2003 in a Scottish Blackface flock. Live BW was recorded every 4 wk from birth to 24 wk. Survival was defined either by perinatal or postnatal mortality (up to weaning at 12 wk), or as cumulative survival to 1, 4, 8, and 12 wk. The pedigree file compr…

Genetic polymorphism at the CSN1S1 gene in Girgentana dairy goat breed

2013

The aim of this work was to evaluate the variability of the αs1-casein locus in the endangered Girgentana dairy goat breed in order to define genetic improvement and a conservation program for this breed. The study was performed on 200 dairy goats by means of different PCR protocols. The most frequent alleles were A (0.590) and F (0.290) followed by B (0.065) and N (0.047). CSN1S1 E allele was identified with a very low frequency (0.008). The most common genotype was AF (0.365) followed by AA (0.340). The high frequency of the strong genotypes is associated with the production of milk with high fat and protein content and with optimal technological properties. In Girgentana goat breed, the …