Stereoselective total syntheses of leiocarpin A and (-)-galantinic acid starting from D-mannitol

Stereoselective total syntheses of leiocarpin A and (-)-galantinic acid, starting from D-mannitol as a chiral synthon, are described. The key steps involve stereoselective allylations, a Grignard reaction to control the required stereogenic centers, and ring-closing metathesis followed by intramolecular Michael addition

Computation of JT-60SA TF coil temperature margin using the 4C code

The recently developed 4C thermal-hydraulic code, currently under validation, is used to compute the temperature margin of the superconducting NbTi toroidal field coil of the ITER satellite tokamak JT-60SA, for the nominal burn operation of the machine. Repetitive conditions in the simulation are reached after two plasma pulses. For given (computed) thermal load distribution on winding and coil case due to nuclear heating only, helium temperature ∼4.4K at the winding inlet, reference strand, and the most recent conductor and winding layout, the computed minimum margin occurs in pancake #7 at the peak field location and turns out to be ∼0.2-0.3K above the design value of 1.2

Conceptual design studies for the European DEMO divertor: Rationale and first results

In the European fusion roadmap, reliable power handling has been defined as one of the most criticalchallenges for realizing a commercially viable fusion power. In this context, the divertor is the key in-vessel component, as it is responsible for power exhaust and impurity removal for which divertor targetis subjected to very high heat flux loads. To this end, an integrated R&D project was launched in theEUROfusion Consortium in order to deliver a holistic conceptual design solution together with the coretechnologies for the entire divertor system of a DEMO reactor. The work package \u2018Divertor\u2019 consistsof two project areas: \u2018Cassette design and integration\u2019 and \u2018Target development\u2019. The essential missionof the project is to develop and verify advanced design concepts and the required technologies for adivertor system being capable of meeting the physical and system requirements defined for the next-generation European DEMO reactor. In this contribution, a brief overview is presented of the works fromthe first project year (2014). Focus is put on the loads specification, design boundary conditions, materialsrequirements, design approaches, and R&D strategy. Initial ideas and first estimates are presented

Progress in the engineering design and assessment of the European DEMO first wall and divertor plasma facing components

The European DEMO power reactor is currently under conceptual design within the EUROfusion Consortium. One of the most critical activities is the engineering of the plasma-facing components (PFCs) covering the plasma chamber wall, which must operate reliably in an extreme environment of neutron irradiation and surface heat and particle flux, while also allowing sufficient neutron transmission to the tritium breeding blankets. A systems approach using advanced numerical analysis is vital to realising viable solutions for these first wall and divertor PFCs. Here, we present the system requirements and describe bespoke thermo-mechanical and thermo-hydraulic assessment procedures which have been used as tools for design. The current first wall and divertor designs are overviewed along with supporting analyses. The PFC solutions employed will necessarily vary around the wall, depending on local conditions, and must be designed in an integrated manner by analysis and physical testing