A biocontrol fungus isolated from rotting wood was identified as a Trichoderma strain (named as Trichoderma sp. ZH1) by internal transcribed spacer (ITS) sequences of rRNA genes. The laccase yield of Trametes sp. AH28-2 in cocultivation with Trichoderma sp. ZH1 reached 6,210 U l(-1), approximately identical to those induced by toxic aromatic inducers. Cocultures maintained 60-70 % of their highest laccase activity obtained at 5 days after inoculation of the biocontrol fungus, at least for 20 days. Furthermore, a novel laccase isozyme (LacC) was obtained through the fungal interactions. The molecular weight of LacC is about 64 kDa, and its isoelectric point is 6.6. The temperature and pH optimum for LacC to oxidize guaiacol are 55 degrees C and 5.0, respectively. LacC is stable both at 60 degrees C and pH 4.0-8.0. Furthermore, the K (m) values of LacC for various substrates were also determined. Our work demonstrates a safe strategy for the production of industrial laccases, instead of the traditional method of chemical induction.

The dynamics of first-order electronic phase transitions in complex transition metal oxides are not well understood but are crucial in understanding the emergent phenomena of electronic phase separation. We show that a manganite system reduced to the scale of its inherent electronic charge-ordered insulating and ferromagnetic metal phase domains allows for the direct observation of single electronic phase domain fluctuations within a critical regime of temperature and magnetic field at the metal-insulator transition.

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A self-assembled MoS/Mo-S-C multilayer film prepared by r.f. co-sputtering of MoS and graphite targets was tribotested in diverse sliding atmospheres, and the lubricant mechanism and its correlations to the selective releasing behavior of non-lubricant component were analyzed in detail. Based on the analysis of composition and structural transformation of transferred materials by Raman and HRTEM characterizations, selective releasing behavior according to the sliding atmospheres were found to be particularly apparent in vacuum and dry inert atmospheres. Under these conditions, a-C in graphitic form was selectively released outwards from the topmost surfaces of contacts, leaving MoS layers finely reordered in (002) orientation playing a lubricant role. Composition and structural transformation were observed not only on the topmost surface of wear track but also on the underlying layer at a thickness of tens of nanometers. Moreover, it was found that the selective releasing of a-C initiated from the center of contacts with higher pressure, and then developed toward the edges, resulting in a gradual change in the composition and microstructure of the transferred materials from the well-aligned MoS layers in the center to the graphitic a-C dominant composites at the edges. The short running-in periods and low-friction performance in all the tribotests suggested that the initial preference of MoS-riched sublayers in (002) orientation may facilitate the formation of shearless tribofilms and therefore provide a feasible way of structural tailoring in the MoS-based lubricant films for an improved triboactive response.