The utilization of silicon-based materials for thermoelectrics is studied with respect to synthesis and processing of doped silicon nanoparticles from gas phase plasma synthesis. It is found that plasma synthesis enables for the formation of spherical, highly crystalline and soft-agglomerated materials. We discuss the requirements for the formation of dense sintered bodies while keeping the crystallite size small. Both, small particles sizing a few ten nanometer and below that are easily achievable from plasma synthesis, and a weak surface oxidation lead to a pronounced sinter activity about 350 K below the temperature usually needed for successful densification of silicon. The thermoelectric properties of our sintered materials are comparable with the best results found for nanocrystalline silicon prepared by other methods than plasma synthesis.

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The article contains sections titled: 1. History 1.1. Centers of Gold Production 1.2. Production 1.3. Development of Production Processes 2. Properties 2.1. Physical Properties 2.2. Chemical Properties 3. Occurrence 3.1. Abundance 3.2. Gold Deposits 3.3. Gold Reserves and Resources 4. Production 4.1. Ore Treatment 4.2. Cyanidation 4.3. Recovery of Gold with Carbon 4.3.1. Adsorption of Gold by Carbon 4.3.2. Carbon‐in‐Pulp Process 4.3.3. Carbon‐in‐Leach Process 5. Gold Refining 5.1. Chemical Refining 5.2. Miller Process 5.3. Wohlwill Electrolysis 5.4. Solvent Extraction 6. Recovery of Gold from Secondary Materials 6.1. Recovery from Gold Alloys 6.2. Recovery from Sweeps 6.3. Recovery from Surface‐Coated Materials 7. Gold Compounds 7.1. Potassium Dicyanoaurate(I) 7.2. Tetrachloroauric(III) Acid 7.3. Sodium Disulfitoaurate(I) 7.4. Miscellaneous Gold Compounds 8. Gold Alloys 8.1. Binary Alloys 8.2. Ternary Alloys 8.3. Higher Alloys 8.4. Production and Processing 9. Quality Specifications and Analysis 9.1. Quality Specifications 9.2. Sampling 9.3. Qualitative and Semiquantitative Analysis 9.4. Quantitative Analysis 9.5. Purity Analysis 9.5.1. Direct Analysis of Metallic Gold 9.5.2. Purity of Gold Solution 9.6. Trace Analysis 10. Uses of Gold and Gold Alloys 10.1. Coins, Medals, and Bars 10.2. Jewelry 10.3. Electronics and Electrical Engineering 10.3.1. Electronics 10.3.2. Electrical Engineering 10.4. Solders 10.5. Pen Nibs 10.6. Chemical Technology 10.7. Dental Materials 10.8. Coatings 10.8.1. Electroplating and Electroforming 10.8.2. Bright Gold 10.8.3. Other Gold Coatings 10.9. Gold Leaf 10.10. Catalysts 11. Economic Aspects 12. Toxicology and Occupational Health

Low-pressure, lean, laminar, premixed hydrogen/oxygen/argon flames seeded with iron pentacarbonyl (35−170 ppm Fe(CO)5) were modeled with detailed chemistry and the results were compared to laser-induced fluorescence imaging measurements of iron atom concentration and gas-phase temperature. The model includes recent rate coefficients for the decomposition of iron pentacarbonyl and thermodynamic data. The simulated iron concentrations correspond well with the measurements with only minor discrepancies in the rise of the iron profiles at low Fe(CO)5 concentrations. In addition, it was shown that the mechanism is able to predict the effect of Fe(CO)5 on the flame speed also for lean conditions, where the model was not established yet. The major iron species, aside from atomic iron, in this flame are predicted to be FeOH and Fe(OH)2 with some FeO2 early in the flame. The observed increased flame temperatures in the presence of Fe(CO)5 are attributed to catalytic hydrogen recombination.

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