1,310 research outputs found
Evidence for partial rotation alignment in proton emitting 121Pr
Abstract Using nonadiabatic quasiparticle calculations we reproduce the experimental half-life for proton radioactivity in 121Pr assuming that the decaying state has angular momentum J π = 7 / 2 − , thus showing for the first time clear evidence for partial rotation alignment in a proton emitting nucleus. The treatment of the pairing interaction in the BCS approach produces profound changes in the ordering of energy levels, and at high deformation, the state 7 / 2 − coming from the h 11 / 2 spherical shell becomes the bandhead
Nonlinear stabilitty for steady vortex pairs
In this article, we prove nonlinear orbital stability for steadily
translating vortex pairs, a family of nonlinear waves that are exact solutions
of the incompressible, two-dimensional Euler equations. We use an adaptation of
Kelvin's variational principle, maximizing kinetic energy penalised by a
multiple of momentum among mirror-symmetric isovortical rearrangements. This
formulation has the advantage that the functional to be maximized and the
constraint set are both invariant under the flow of the time-dependent Euler
equations, and this observation is used strongly in the analysis. Previous work
on existence yields a wide class of examples to which our result applies.Comment: 25 page
Design Concepts for Peel-Dominant Adhesive Joints in Aeronautic Applications
The adhesive bonding technique is employed from the aeronautical/aerospace industry to current house products. To comply with the requirements of distinct applications, different joint configurations are available to the designer. While single-lap joints (SLJ) are the most common in application and research, double-lap joints, scarf joints and T-joints find specific applications. T-joints are seldom studied in the literature, but these are used, for instance, in aircraft to bond the stiffener beams to the skin, or in the cars between the B-pillar and the rocker. Due to the high stress concentrations, T-joints often fail under average stresses much lower than the adhesive strengths, giving rise to the necessity for proper design and strength improvement methodologies. This work initially aims to validate the cohesive zone modelling (CZM) technique with experiments, and then use it to numerically evaluate and optimize the performance of T-joints subjected to peel loads. CZM is nowadays regarded as the most powerful strength prediction tool for adhesive joints, and can be a valuable tool to improve T-joints. Different features are addressed for a complete analysis: adhesive type, geometrical parameters, dual-adhesive technique for strength improvement, and composite joints. The evaluated geometrical parameters are the base adherend thickness (a), T-part thickness (t), overlap or bonding length (l) and curvature radius (r). As a result of this work, the model was successfully validated, and clear design guidelines were provided to define the ideal geometric and material (adhesive) conditions for best performance
An Extension Of Marchioro's Bound On The Growth Of A Vortex Patch To Flows With Lp Vorticity
We observe that C. Marchioro's cubic-root bound in time on the growth of the diameter of a patch of vorticity [Comm. Math. Phys, 164 (1994), pp. 507-524] can be extended to incompressible two-dimensional Euler flows with compactly supported initial vorticity in Lp, p > 2, and with a distinguished sign.293596599Delort, J.-M., Existence de nappes de tourbillons en dimension deux (1991) J. Amer. Math. Soc., 4, pp. 553-586Majda, A., Vorticity and the mathematical theory of incompressible fluid flow (1986) Comm. Pure Appl. Math., 39, pp. S187-S220Marchioro, C., Bounds on the growth of the support of a vortex patch (1994) Comm. Math. Phys., 164, pp. 507-524Schocket, S., The weak vorticity formulation of the 2D Euler equations and concentration-cancellation (1995) Comm. Partial Differential Equations, 20, pp. 1077-110
Composição esterólica e em ácidos gordos de azeites monovarietais provenientes das regiões de Elvas, Castelo Branco e Santarém
Comunicação apresentada no III Simpósio Nacional de Olivicultura que decorreu em Castelo Branco, na Escola Superior Agrária do Instituto Politécnico de Castelo Branco, de 29 a 31 de Outubro de 2003.Neste trabalho apresenta-se um estudo efectuado em cinco azeites monovarietais
(Olea europaea ‘Cordovil De Castelo Branco’, ‘Cobrançosa’, ‘Conserva De Elvas’,
‘Galega Vulgar’ e ‘Picual’). O estudo reporta-se a três campanhas consecutivas
(2000/03) e o material experimental provém de olivais situados em três regiões
portuguesas, nomeadamente Elvas, Castelo Branco e Santarém. Os azeites foram
extraÃdos em equipamento Oliomio e as análises foram: ácidos gordos, esteróis e álcoois
triterpénicos (eritrodiol + uvaol). Dos resultados obtidos, o azeite ‘Cordovil De Castelo
Branco’ destaca-se pelos seus teores elevados em eritrodiol + uvaol nas três regiões em
estudo. Por seu turno, o teor de ácido oleico do azeite ‘Galega Vulgar’ permite
distinguir cada uma das regiões, enquanto no azeite ‘Cobrançosa’ o teor em esteróis
totais distingue as três regiões
Is PCBs concentration variability between and within freshwater fish species explained by their contamination pathways?
Many chemical, physiological, and trophic factors are known to affect ioaccumulation of polychlorinated biphenyls (PCBs) in biota. Understanding the primary factors affecting fish contamination is critical for predicting and assessing risks to upper-trophic level consumers, including humans. Here we identify PCB contamination pathways that could explain within- and between-species variability in fish concentration levels. Three freshwater river fish species (barbel, chub and bream) were sampled at three sites along the Rhone River (France) where fish consumption is partially prohibited because of PCB levels exceeding the European health-based benchmark. The trophic position was assessed using an innovative approach based on stable isotope analyses and Bayesian inference, which takes into account both isotope data variability and parameter uncertainty. The effect of foraging habitat on fish contamination was addressed using stable isotope mixing models. The fish trophic position and PCB concentrations were found to be unrelated while the exploitation of sediment detrital carbon as a food source appeared to be a critical factor affecting fish contamination. Fish length, PCB concentration of the sediment, and individual fish foraging habitat (exploitation of detrital versus planktonic carbon sources) explained 80% of within- and between-species variability observed in PCB concentrations. These results, obtained for species that have overlapping TPs and exploit different carbon sources, reveal that the important factor in fish PCB contamination is not only what fish consume, but also and essentially the feeding location
i-Farm: A exploração vitÃcola inteligente da sociedade da informação e do conhecimento
www.i-Farm.pt.Neste trabalho iremos explorar o potencial das mais recentes inovações
tecnológicas disponÃveis no mercado para construir a i-Farm, a exploração vitÃcola inteligente da sociedade da informação e do conhecimento. O projecto
i-Farm foi financiado pelo Programa DEMTEC da Agência de Inovação, apesar
de passÃvel de ser aplicado em qualquer actividade agrÃcola, é apresentado
para o caso concreto da vinha, pois a viticultura foi considerada estratégicas
no âmbito do Plano Estratégico Nacional para o Desenvolvimento Rural
Português (GPP, 2007), numa lógica de aumento da competitividade do sector
agrÃcola, conforme previsto no Eixo 1 da referida estratégia.
A viticultura, mais concretamente a viticultura de precisão, tem vindo a receber
uma atenção crescente da comunidade cientÃfica e empresarial na medida em
que é efectivamente uma actividade capital intensivo em que a realização de
investimentos em tecnologias de informação e comunicação podem ser
justificados numa análise custo/benefÃcio rigorosa. É hoje possÃvel encontrar
na literatura cientÃfica e nas empresas de prestação de serviços especializados
exemplos concretos da aplicação das mais recentes tecnologias de
monitorização remota sem fios na vinha (Camilli et al., 2007, Morais et al.,
2008, Neto et al. 2007). Neste projecto quisemos ir mais longe na utilização
das tecnologias disponÃveis para construir um sistema integrado de apoio Ã
decisão numa abordagem de Business Intelligence e estudar a utilização de
digital dashboards para suportar a tomada de decisão ao nÃvel da exploraçãoinfo:eu-repo/semantics/publishedVersio
Is dilution of cows'milk formula necessary for dietary management of acute diarrhoea in infants aged less than 6 months?
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