Search results for "fusion [vector boson]"
showing 10 items of 526 documents
Semi-empirical simulations of F-center diffusion in KCl crystals
1997
Abstract The semi-empirical method and 224 atom quantum clusters were used for calculating the activation energy for diffusion of cation and anion vacancies and F-centers in KCl crystals. The relevant activation energies of 1.19 eV, 1.44 eV and 1.64 eV, respectively agree well with the experimental data.
Analysis of the Diffusion-Induced Stress Effect on the Oxidation in Finely Divided Vanadium Ferrites
1999
L'oxydation isotherme des cations fer(II), vanadium(II) et vanadium(III) pour les ferrites spinelles finement divises, lesquels sont oxydes en phases deficitaires en cations, a ete etudiee par thermogravimetrie. La faible temperature de cinetique d'oxydation de chaque cation oxydable a ete expliquee en considerant que l'oxydation genere des contraintes qui en modifie la cinetique ou les cations a la surface sont plus oxydes que dans le volume. Pour cela, il at ete considere que le coefficient de diffusion chimique est donne par la relation D = D 0 exp [-(E' a + pV a )/RT] ou D 0 represente le facteur pre-exponentiel, E' a l'energie d'activation, V a le volume d'activation et p la pression i…
Fabra and the linguistic authority in the Valencian Country: the Philological Section of Institut d’Estudis Valencians (1937-1939)
2019
Davant la dificultat d’acceptar al País Valencià l’autoritat lingüística de l’IEC i la codificació de la llengua catalana, Fabra reconegué en almenys tres declaracions (1918, 1930 i 1937), que corresponia als escriptors valencians la tasca de depurar i de redreçar la llengua i admeté que la constitució d’un centre d’estudis filològics al País Valencià hi podria ajudar. No es pronuncià sobre les Normes de Castelló, però s’interessà per la seua aplicació i, com a president de l’IEC, mantingué una bona relació amb l’Institut d’Estudis Valencians (1937-1939), creat per Francesc Bosch i Morata a imitació de l’IEC. La creació de l’Institut d’Estudis Valencians (= IEV) fou una aspiració constant d…
Nonlinear Diffusion in Transparent Media
2021
Abstract We consider a prototypical nonlinear parabolic equation whose flux has three distinguished features: it is nonlinear with respect to both the unknown and its gradient, it is homogeneous, and it depends only on the direction of the gradient. For such equation, we obtain existence and uniqueness of entropy solutions to the Dirichlet problem, the homogeneous Neumann problem, and the Cauchy problem. Qualitative properties of solutions, such as finite speed of propagation and the occurrence of waiting-time phenomena, with sharp bounds, are shown. We also discuss the formation of jump discontinuities both at the boundary of the solutions’ support and in the bulk.
Cataclastic solution creep of very soluble brittle salt as a rock analogue
1998
Until about the late 1960s, macroscopically ductile deformation of quartz was seen as a microscopically cataclastic process by most geologists (cf. the origin of the name ‘mylonite’). Undulatory extinction, subgrains, recrystallised grains and even crystallographic preferred orientations were interpreted as due to water-assisted brittle deformation processes. Nowadays, by contrast, the occurrence of these optical microstructures is considered as conclusive and unequivocal evidence for dislocation creep. The abundance of these microstructures in naturally deformed rocks lead to the conclusion that dislocation creep is the most important ductile deformation mechanism within the Earth’s crust.…
Integral approach to the safety design of the EU-DEMO Helium-Cooled Pebble Beds with reference to the associated relevant systems
2020
Estrategias locales de capacitación profesional y desarrollo local: el caso de Gandia, España
2009
En los últimos años, Gandia, una ciudad media del mediterráneo español, se ha convertido en un ejemplo de crecimiento económico mientras que, al mismo tiempo, enfrenta retos importantes. Estos incluyen la llegada de un relevante flujo de inmigrantes y la necesidad de adaptar el sistema económico local y el mercado de trabajo a un entorno cada vez más competitivo. Desde 1998 el Centro de Servicios Integrales de la municipalidad (CSI-COM) ha liderado un proceso de cooperación de los agentes locales para afrontar estos desafíos. CSI-COM constituye un ejemplo de buena práctica en la mejora del funcionamiento del mercado de trabajo local. Sus principales herramientas son la formación de recursos…
Business owners, employees, and firm performance
2018
The novel Finnish Longitudinal OWNer-Employer-Employee (FLOWN) database was used to analyze how the characteristics of owners and employees relate to firm performance as determined by labor productivity, survival, and employment growth. Focusing on the role of the employment history, the results show that previous experience in a high-productivity firm strongly predicts high productivity and probability of survival for the entrepreneur’s new firm. This can be interpreted as evidence of knowledge spillovers through labor mobility of both the owners and the employees. The results also show that the owner’s high education in a technical field is positively related to firm performance. Differen…
Electrochemical treatment of paper mill wastewater by electro-Fenton process
2019
Abstract The electrochemical oxidation of organics in paper mill wastewater belonging to Halfa industries (Tunisia) was performed by galvanostatic electrolyses using electro-Fenton (EF) process. The effect of several operating parameters, such as applied current density, electrodes material, air pressure and the presence of sodium chloride (NaCl) was evaluated. In particular, carbon felt (CF), modified carbon felt (MCF) and gas diffusion electrode (GDE) were used as cathode while Ti/IrO2-Ta2O5 and Boron Doped Diamond (BDD) as anode. Total Organic Carbon (TOC) measure was chosen as reference parameter to assess the extent of the treatment. The experimental results show that, by adopting the …
Ab Initio Calculations of the Transfer and Aggregation of F Centers in CaF2
2012
The F center and R center in CaF2 crystals have been studied by using density functional theory (DFT) with a hybrid B3PW description of exchange and correlation. Our calculations show that the F-center diffusion barrier is equal to 1.67 eV. During the F-center transfer, the trapped electron is more delocalized than that in the regular F-center case, and the gap between defect level and CB in the α-spin state decreases. The surface F-center investigation shows the trend of F centers to locate near the surface. The association energy calculations of R centers indicate stable aggregations of isolated F centers. During the F-center aggregation, a considerable covalency forms between two neighbo…