Comparison between cocoa and chocolate: characterisation and fatty acid content

The connection between chocolate and cocoa is studied. As cocoa is produced in different countries, samples coming from the same geographical region are analysed. The analyses focus on the characterisation of the considered samples for different aspects of quality and to individuate the original locations of production, also connecting this with the nutritional aspects. For this purpose, qualitative and quantitative traditional analysis and determination of fatty acid content are performed. The obtained experimental data show interesting correlations. The percentages of fatty acids computed allow for distinctions to be made among cocoa and chocolate samples. Furthermore, a relation can be assumed among the data obtained for primary matters and final products corresponding to countries being positioned on the same latitude, even if they are situated in different continents.     

Self-energy and vertex radiative corrections in LQG

We consider the elementary radiative-correction terms in loop quantum gravity. These are a two-vertex “elementary bubble” and a five-vertex “ball”; they correspond to the one-loop self-energy and the one-loop vertex correction of ordinary quantum field theory. We compute their naive degree of (infrared) divergence.     

Reduced basis method for multi-parameter-dependent steady Navier–Stokes equations: Applications to natural convection in a cavity

This work focuses on the approximation of parametric steady Navier–Stokes equations by the reduced basis method. For a particular instance of the parameters under consideration, we are able to solve the underlying partial differential equations, compute an output, and give sharp error bounds. The computations are split into an offline part, where the values of the parameters are not yet identified, but only given within a range of interest, and an online part, where the problem is solved for an instance of the parameters. The offline part is expensive and is used to build a reduced basis and prepare all the ingredients – mainly matrix–vector and scalar products, but also eigenvalue computations – necessary for the online part, which is fast.     

Extrinsic symplectic symmetric spaces

We define the notion of extrinsic symplectic symmetric spaces and exhibit some of their properties. We construct large families of examples and show how they fit in the perspective of a complete classification of these manifolds. We also build a natural ?$?$-quantization on a class of examples.     

Coherence transfer between spy nuclei and nitrogen-14 in solids

Coherence transfer from 'spy nuclei' such as (1)H or (13)C (S=1/2) was used to excite single- or double-quantum coherences of (14)N nuclei (I=1) while the S spins were aligned along the static field, in the manner of heteronuclear single-quantum correlation (HSQC) spectroscopy. For samples spinning at the magic angle, coherence transfer can be achieved through a combination of scalar couplings J(I,S) and second-order quadrupole-dipole cross-terms, also known as residual dipolar splittings (RDS). The second-order quadrupolar powder patterns in the two-dimensional spectra allow one to determine the quadrupolar parameters of (14)N in amino acids.     

Role of 3D imaging in small scale NMR tomography

Some advantages of using 3D techniques in small scale NMR imaging are suggested. In particular the 3D methods are likely to be useful in slow dynamical processes occurring in vivo. Three-dimensional images obtained with our first home built prototype are also reported.     

Invariant*-products of holomorphic functions on the hyperbolic hermitian spaces

In this paper, we give an explicit basis of the invariant bidifferential operators on the Hermitian symmetric spaces of rank 1. As an application we prove that on noncompact Hermitian symmetric spaces of rank 1, an invariant^*-product coincides with the usual product for holomorphic functions.Aspirant du Fonds National Belge de la Recherche Scientifique.