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A power-balance model, with radiation losses from impurities and neutrals, gives a unified description of the density limit (DL) of the stellarator, the L-mode tokamak, and the reversed field pinch (RFP). The model predicts a Sudo-like scaling for the stellarator, a Greenwald-like scaling, , for the RFP and the ohmic tokamak, a mixed scaling, , for the additionally heated L-mode tokamak. In a previous paper (Zanca et al 2017 Nucl. Fusion 57 056010) the model was compared with ohmic tokamak, RFP and stellarator experiments. Here, we address the issue of the DL dependence on heating power in the L-mode tokamak. Experimental data from high-density disrupted L-mode discharges performed at JET, as well as in other machines, are taken as a term of comparison. The model fits the observed maximum densities better than the pure Greenwald limit.

Hexanuclear complexes [Pt,Ag,(C=CR),] [R = Ph (1) or But (2)] have been obtained by treating [PtCl,(tht),] (tht = tetrahydrothiophene) with [Ag(C=CR)],( Pt/Ag 1 : 4). The complexes [Pt,M,(CrCR),] [M = Cu, R = Ph (3) or But (4); M = Au, R = But ( 5 ) ] were obtained from [Pt,Ag,( CzCR),] with CuCl or [AuCl(tht)] respectively. Alternatively, the reactions between [N Bu,],[Pt (CKR),] and AgCIO,, CuCI-NaCIO,, or [AuCl (tht)]-NaClO, yield respectively complexes (1)-(5). The molecular structure of [Pt,Ag,(C=CBut),]has been determined b y an X-ray diffraction study: monoclinic, space group C, with a = 37.062( 7), b = 12.0223( 16), c = 20.459(3) A, p = 107.485(15)0, Z = 6, R 0.041 6, R' 0.0465 for 5 61 3 reflections with F > 6o(F). The six metal atoms are arranged in a slightly irregular octahedron with the platinum atoms mutually trans and the silver atoms in the equatorial plane, with Pt A g and A gA g distances longer than 3.0 A.Each platinum atom is in an almost square-planar environment formed b y four C=CBut ligands. Each acetylenic fragment also forms an asymmetric n: interaction with one silver atom of the equatorial positions so that each silver atom is bonded to t w o acetylenic fragments, of two different Pt(C=CBut), moieties. These moieties of each [Pt,Ag,(C=C6ut),] unit are staggered.Substituted acetylides are very useful ligands in the syntheses of polynuclear derivatives. These usually contain metal-metal bonds and in such species the acetylides can either be coordinated to the cluster as terminal ligands, e.g. [Au6Pt(C= CBU')(PM~~)~][AU(C=CBU')~],~ or as bridging ligands, e.g.: p-(T in [ C U ~( C = C C ~H , M ~-~) ~R , ] , ~ p3-0 in [(Cu(PPh,)(C= CPh)}4],3 p-q2 in [CU,I~(C=CP~),(PP~~),],~ p3-q2 in[ Rh Ag , ( C=CC6 F 5 ) (PP h 3) 3], and p4-q in [R u ( C g P h)( p-

The 2014–2016 JET results are reviewed in the light of their significance for optimising the ITER research plan for the active and non-active operation. More than 60 h of plasma operation with ITER first wall materials successfully took place since its installation in 2011. New multi-machine scaling of the type I-ELM divertor energy flux density to ITER is supported by first principle modelling. ITER relevant disruption experiments and first principle modelling are reported with a set of three disruption mitigation valves mimicking the ITER setup. Insights of the L–H power threshold in Deuterium and Hydrogen are given, stressing the importance of the magnetic configurations and the recent measurements of fine-scale structures in the edge radial electric. Dimensionless scans of the core and pedestal confinement provide new information to elucidate the importance of the first wall material on the fusion performance. H-mode plasmas at ITER triangularity (H  =  1 at βN ~ 1.8 and n/nGW ~ 0.6) have been sustained at 2 MA during 5 s. The ITER neutronics codes have been validated on high performance experiments. Prospects for the coming D–T campaign and 14 MeV neutron calibration strategy are reviewed.

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The alkynylation of [Cp*MX 2 (PEt 3 )] (Cp* ) η 5 -C 5 Me 5 ; X ) Cl, M ) Rh; X ) I, M ) Ir) with an excess of LiCtCR (R ) Ph (a), t Bu (b), SiMe 3 (c)) in thf leads to novel bis(alkynyl)) complexes depending on the reaction time. Complex 4a and the related (phenylethynyl)iridium derivatives [Cp*Ir(CtCPh)X(PEt 3 )] (X ) Cl, 2a; X ) I, 2a′) can be prepared by reactinga′,c′), Pd (12a,a′,c′)) heterodinuclear compounds. Complexes 5a,c and 7a,c can, alternatively, be obtained through a neutralization reaction between the dianionic complexes Qand solvento species [Cp*M(PEt 3 )(acetone) 2 ](ClO 4 ) 2 (M ) Rh, Ir) (prepared in situ). The molecular structures of the heterobridged Rh-Pt (9b) and Ir-Pd (12a) and homobridged Rh-Pt (5c), Ir-Pt (7a,c), and Ir-Pd (8a) complexes have been determined by X-ray analyses. In the iridium mixed complexes 7a,c, 8a, and 12a the alkynyl ligands are σ-bonded to iridium and π-bonded to Pt (7a,c) or Pd (8a, 12a) centers. In contrast, the crystal structure of 5c shows a dinuclear zwitterionic complex formed by two different alkynyl organometallic termini, [Cp*Rh + (CtCSiMe 3 )(PEt 3 )] and [cis-Pt -(C 6 F 5 ) 2 (CtCSiMe 3 )], held together through η 2 -bonding of the alkynyl groups.

The partition of a series of substituted phenols between water and polymer micelles formed by potassium salts of poly(maleic acid-co-1-olefins), PA-nK2 with n ranging from 6 to 18, has been investigated. Steady-state and time-resolved fluorescence measurements have been used to study the formation and properties of these micelles. The data indicate that just PA-6K2 exhibits a pH-induced conformational transition. All other copolymers adopt a compact configuration over the entire pH range. The hydrophobicity of these microdomains, as measured by the ratio III/I, increases with the length of the side alkyl chain. The aggregation number, i.e., the number of monomer units involved in the intramolecular micelle, has been found to be equal to the degree of polymerization, suggesting that one polymer chain forms one polymer micelle. The transfer free energies of p-alkyl-substituted phenols from water to PA-18K2 and of phenol from water to PA-nK2 have been measured. The contribution of each methylene group to the free energy is 0.97 and 0.34 kJ mol-1 in the substituted phenol and the side alkyl chain, respectively. These values are lower than those determined for transfer of phenols to ionic micelles and to heptane.