Understanding precursor transformation to active catalysts is crucial to heterogeneous Fischer-Tropsch (FT) catalysis directed towards production of hydrocarbons for transportation fuels. Despite considerable literature on FT catalysis, the effect of pre-treatment of supported cobalt catalysts on cobalt dispersion, dynamic atomic structure and the activity of the catalysts is not well understood. Here we present systematic studies into the formation of active catalyst phases in supported Co catalyst precursors in FT catalysis using in-situ environmental (scanning) transmission electron microscopy (E(S)TEM) with single atom resolution under controlled reaction environments for in-situ visualization, imaging and analysis of reacting atomic species in real time, EXAFS, XAS, DRIFTS analyses and catalytic activity measurements. We have synthesized and analyzed dried-reduced (D) and dried-calcined reduced (DC) Co real catalysts on reducible and non-reducible supports, such as SiO2, Al2O3, TiO2 and ZrO2. Comparisons of dynamic in-situ atomic structural observations of reacting single atoms, atomic clusters and nanoparticles of Co, DRIFTS, XAS, EXAFS and catalytic activity data of the D and DC samples reveal in most cases better dispersion in the D samples, leading to a larger number of low-coordination Co 0 sites and a higher number of active sites for CO adsorption. The experimental findings on the degree of reduction of D and DC catalysts on reducible and non-reducible supports and correlations between hexagonal (hcp) Co sites and the activity of the catalysts generate structural insights into the catalyst dynamics, important to the development of efficient FT catalysts.

Light without fright: A synthetic route to fluorescent primary phosphanes (RPH2) that are resistant to air oxidation both in the solid state and in chloroform solution is described. These versatile precursors undergo hydrophosphination to give tripodal ligands and subsequently fluorescent transition‐metal complexes.

The structural features required for mitochondrial uptake of BODIPY-based optical imaging agents have been explored. The first derivatives of this class of dyes shown to have mitochondrial membrane potential-dependent uptake in both cancer and heart cells have been developed.

A fluorescent tridentate phosphine, BodP3 (2), forms rhenium complexes which effectively image cancer cells. Related technetium analogues are also readily prepared and have potential as dual SPECT/fluorescent biological probes.

The syntheses of highly fluorescent analogues of PPh3 and PhPCy2 based on the Bodipy chromophore are described. The ligands have been incorporated into two- to four-coordinate group 11 metal complexes. The synthesis, characterisation and photophysical properties of the novel ligands and their metal complexes are reported; many of these compounds have also been characterised by single-crystal X-ray diffraction. Incorporation of the phosphino group and complexation to the group 11 metal centre has little effect on the absorption and emission profiles; high molar extinction coefficients and fluorescence quantum yields were still obtained. In particular, incorporation of the dicyclohexylphosphino substituent significantly increases the quantum yields relative to the parent dyes.

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D. Fatty acid balance studies in term infants fed formula milk containing long-chain polyunsaturated fatty acids. Acta Paediatr 1998; 87: 136-42. Stockholm. ISSN 0803-5253 Long-chain polyunsaturated fatty acids (LCP) are thought to be required for optimal nervous system development in the newborn. A commercial milk formula containing LCP (Aptamil-LCP) with a fatty acid profile closely resembling breast milk, has recently been introduced for term infants. The absorption of fatty acids in term infants was examined in a double-blind randomized controlled trial comparing Aptamil-LCP (n ¼ 20) and standard Aptamil (n ¼ 20). Formula-fed newborn infants were studied from birth for 14 d. Fat balances (3 d) were performed from d 10. A 3-d stool collection was performed from d 10 in a parallel breastfed group (n ¼ 21). Plasma samples were taken on d 6. Median fat excretion (mg kg -1 ) was 897.1, 615.0 and 355.2 with Aptamil, Aptamil-LCP and breastfeeding, respectively. The median total fat absorption coefficient in Aptamil-LCP-fed infants was higher than in those fed standard Aptamil (p Ͻ 0:01). These findings were accounted for by differences in the excretion and absorption of long-chain saturated fatty acids (C14:0, C16:0 and C18:0). Higher fat excretion was associated with bulkier and firmer stools. Only trace amounts of LCP were detected in the stools of all groups. This accounted for less than 4% of dietary intake in Aptamil-LCP-fed infants. No differences in the utilization of LCP from Aptamil-LCP and breast milk feeding were apparent. Plasma phospholipid fatty acid composition data reflected differences in dietary LCP intake. Thus, PL LCP levels were highest in the breastfed infants and lowest in the Aptamil-fed infants, with values for the Aptamil-LCP-fed group falling in between. ٖ Fat balance, polyunsaturated fatty acids, term infant formula

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