Registered Charity Number 207890 Cyclic stability of an iron-based conversion material was greatly improved through a carbon-Fe-LiF nanocomposite cathode material obtained by pyrolysis of a ferrocene/lithium fluoride mixture. The product consists of Fe nanoparticles which are intimately embedded in porous and multiwalled nanocarbon structures.

We probe the role of carbon in the ultraviolet (UV) extinction by examining the relations between the amount of carbon required to be locked up in dust [C/H] dust with the 2175Å extinction bump and the far-UV extinction rise, based on an analysis of the extinction curves along 16 Galactic sightlines for which the gas-phase carbon abundance is known and the 2175Å extinction bump exhibits variable strengths and widths. We derive [C/H] dust from the Kramers-Kronig relation which relates the wavelength-integrated extinction to the total dust volume. This approach is less model-dependent since it does not require the knowledge of the detailed optical properties and size distribution of the dust. We also derive [C/H] dust from fitting the observed UV/optical/near-infrared extinction with a mixture of amorphous silicate and graphite. We find that the carbon depletion [C/H] dust tends to correlate with the strength of the 2175Å bump, while the abundance of silicon depleted in dust shows no correlation with the 2175Å bump. This supports graphite or polycyclic aromatic hydrocarbon (PAH) molecules as the possible carrier of the 2175Å bump. We also see that [C/H] dust shows a trend of correlating with 1/R V , where R V is the total-to-selective extinction ratio, suggesting that the far-UV extinction is more likely produced by small carbon dust than by small silicate dust.

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Here we report on the magnetic properties of iron carbide nanoparticles embedded in a carbon matrix. The granular distribution of nanoparticles in an inert matrix, of potential use in various application, were prepared by pyrolysis of organic precursors using thermal assisted chemical vapour deposition method. By varying the precursor concentration and preparation temperature, compositions with varying iron concentration and nanoparticle sizes were made. Powder X-ray diffraction, Transmission Electron Microscopy and Mössbauer spectroscopy studies revealed, the nanocrystalline iron carbide (Fe 3 C) presence in the partially-graphitized matrix. The dependence of magnetic properties on the particle size and temperature (10 K

Spinning small silicate grains were recently invoked to account for the Galactic foreground anomalous microwave emission. These grains, if present, will absorb starlight in the far ultraviolet (UV). There is also renewed interest in attributing the enigmatic 2175Å interstellar extinction bump to small silicates. To probe the role of silicon in the UV extinction, we explore the relations between the amount of silicon required to be locked up in silicates [Si/H] dust and the 2175Å bump or the far-UV extinction rise, based on an analysis of the extinction curves along 46 Galactic sightlines for which the gas-phase silicon abundance [Si/H]