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Metal clusters and nanoparticles (NPs) have been studied intensively due to their unique chemical, physical, electrical, and optical properties, resulting from their dimensions, which provided host of applications in nanoscience and nanotechnology. Formation of new materials by embedding NPs into various matrices (i.e. formation of nanocomposites) further expands the horizon of possible application of such nanomaterials. In the last few decades, the focus was put on the formation of metallic and metal oxide NPs via a so-called gas aggregation nanoparticle source employing magnetron sputtering (i.e. Haberland concept). In this paper, an overview is given of the recent progress in formation and deposition of NPs by the gas aggregation method. Examples range from noble metals (Ag, Au) through reactive metals (Al, Ti) to Si and the respective oxides. Emphasis is placed on the mechanism of nanoparticle growth and the resulting properties. Moreover, kinetic Monte Carlo simulations were developed to explain the growth mechanism and dynamics of nanoparticle formation depending on the experimental conditions. In addition, the role of trace amounts of reactive gases and of pulsed operation of the plasma on the nucleation process is addressed. Finally, the treatment of the NPs in the plasma environment resulting in nanoparticle charging, morphological and chemical modifications is discussed.

An overview on particle-based simulation of nanocomposite formation in a magnetron plasma is given. After discussing recent kinetic Monte Carlo results for metal cluster growth and diffusion, new results for the simulation of co-sputtering of metal and polymer are presented. Then, the second method based on molecular dynamics is discussed and time-resolved results for the coalescence of two clusters in the plasma are shown. We conclude with an outlook on the prospects for an integrated simulation of cluster growth in the plasma coupled to the surface deposition phase (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

We prepared charcoals from bamboo, scrap wooden formwork and corn-cobs. Each of these charcoal powders was mixed with rice bran as a nutrient in a weight ratio of 1: 1.15.(Rice bran had previously been used as a model biomass waste for composting.) The moisture content of the mixture was adjusted to 65 %. Aerobic complex microorganisms were added to the biomass waste mixture to seed the composting. Samples were maintained in ambient air (RH 53 %, 23°C) and stirred vigorously with a spatula once a day for aeration. Scanning electron microscopy revealed microorganisms on the surface of the charcoal and in the mouths of the charcoal pores.Measurement of adenosine triphosphate concentrations of the samples revealed that the microorganisms had proliferated in the systems containing charcoal.It was suggested that this proliferation was attributed to supplying abundant oxygen for microorganisms because the charcoal has a lot of pores. Another reason why the charcoal facilitated microorganisms proliferation might be that the microorganisms on the surface of the charcoal were able to be supported in the pores of a sub-micron scale in the charcoal as a matrix might be.