Synthesis of ABC miktoarm star block copolymers from a new heterotrifunctional initiator by combination of ATRP and ROP

We described the obtention of well-defined ABC star block copolymers through the use of a new heterotrifunctional initiator. That way, well-defined PCL-arm–PS-arm–PLLA star block copolymers have been synthesized from a heterotrifunctional initiator bearing two hydroxyl groups able to initiate ROP of CL and LLA (using Sn(Oct)₂ as coinitiator) and a bromide function able to initiate ATRP of styrene.     

Realization and simulation of wall shear stress integrated sensors

In this paper we present the impact of hot wire geometry and fluid characteristics on the efficiency of a hot wire to be used as a wall shear stress sensor. Finite differences and finite elements modelling based simulators were used in order to evaluate the thermal performances of hot wire wall shear stress sensor. Several structures were explored including simple conductor or suspended above a cavity (free and sealed with an oxide membrane). It is found out that wire length, wire section and the dimensions of the micro-cavity lying below the hot wire are of fundamental importance on the thermal exchanges occurring between the hot wire and the fluid.     

Engine calibration: multi-objective constrained optimization of engine maps

We present two new approaches to address the optimization problem associated with engine calibration. In this area, the tuning parameters are traditionally determined in a local way, i.e., at each engine operating point, via a single-objective minimization problem. To overcome these restrictions, the first method we propose is able to cope with several objective functions simultaneously in the local formulation. The second method we put forward relies on a global formulation, which allows the whole driving cycle to be taken into account while remaining single-objective. At the practical level, the two methods are implemented by combining various existing techniques such as the LoLiMoT (Local Linear Model Tree) parameterization and the MO-CMA-ES (Multi-Objective Covariance Matrix Adaptation Evolution Strategy) algorithm. A better compromise appears to be achieved on real case applications.     

Cask and plug handling system design in port cell

The ITER maintenance strategy relies partly on the remote transfer of components from vacuum vessel to hot cells. This function will be fulfilled by transfer cask systems.This paper describes the recent design progresses on interfaces in order to increase components handling feasibility by implementing continuous guiding features that avoid cantilevered loads on the in-cask tractor. Also the design has progressed in order to allow generic docking of the casks.When the cask is connected to the port, it becomes part of the machine first confinement boundary, thus it must provide tightness continuity. This high level safety function was one of the main concerns of a finite element analysis study that has been performed to assess the behavior of the whole system. Numerical analysis methodology and results are explained and shown in order to highlight how it has reinforced the knowledge of the system.     

Easy methods for the electropolymerization of porphyrins based on the oxidation of the macrocycles

Two different methods of electropolymerization of porphyrins have been investigated and compared. They consist in the nucleophilic attack of Lewis bases onto electrogenerated dications of octaethylporphyrins. In the first method, a nucleophilic group has been directly grafted onto the macrocycle (ZnOEP-meso-bpy⁺), while in the second one, free di-nucleophilic compounds (Nu–Nu) have been used in presence of a non-substituted porphyrin (ZnOEP). The advantage of the second method is to easily modify the nature of the bridging spacer between the macrocycles. Characterizations of the polymer obtained from the second method in the case of dipyridinium-tetrazine spacer are presented.     

Corrosion behaviour of zinc–cerium alloys: Role of intermetallic phases

New zinc–cerium alloys (up to 5 wt.%) was synthesized and their corrosion behaviour was studied in a reference corrosive media. Metallographic analyses show that cerium is exclusively present in a Zn₁₁Ce intermetallic phase, homogeneously dispersed in the zinc matrix. With an optimal concentration at around 1.5 wt.%, the Zn₁₁Ce phase acts as a tank of cerium to form a protective Ce-enriched passive layer. Nevertheless, at high Ce content, the benefit in terms of corrosion resistance obtained by the incorporation of Ce in the corrosion layer is shaded by the galvanic coupling between the intermetallic phase and the matrix.     

Artificial photosynthesis at soft interfaces

The concept of artificial photosynthesis at a polarised liquid membrane is presented. It includes two photosystems, one at each interface for the hydrogen and oxygen evolution respectively. Both reactions involve proton coupled electron transfer reactions, and some ultrafast steps at the photosensitization stage.     

Bispectral analysis and reconstruction in the frequency domain of mono- and bidimensional deterministic sampled signals

Deterministic sampled signals bispectra are periodic and hold more information than analog signal bispectra. After showing this difference, the communication presents two algorithms for reconstructing a sampled signal Fourier transform from its bispectrum: the first is a least squares reconstruction method deducing the Fourier transform logarithm from the bispectrum logarithm through a simple average; the second is an algorithm for reconstructing the Fourier transform from a restricted number of values on the bispectrum diagonal slice by a simple resolution of linear equations. The resistance of both algorithms to the measurement noise is given.