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Seven known metabolites, dianhydro-aurasperone C (1), isoaurasperone A (2), fonsecinone A (3), asperpyrone A (4), asperazine (5), rubrofusarin B (6) and (R)-3-hydroxybutanonitrile (7), were isolated from the culture of Aspergillus sp. KJ-9, a fungal endophyte isolated from Melia azedarach and identified by spectroscopic methods. All isolates were evaluated in vitro against several phytopathogenic fungi (Gibberella saubinetti, Magnaporthe grisea, Botrytis cinerea, Colletotrichum gloeosporioides and Alternaria solani) and pathogenic bacteria (Escherichia coli, Bacillus subtilis, Staphyloccocus aureus and Bacillus cereus). Compounds 3 and 7 were active against almost all phytopathogenic fungi tested with minimum inhibitory concentration (MIC) range of 6.25-50 μM. Moreover, compound 3 was active against all pathogenic bacteria with MIC in the range of 25-100 μM. Compound 7 is a rare new natural product isolated from a natural source for the first time, and the detailed NMR data of 1 were first assigned.

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Negative thermal expansion Zr 2 WP 2 O 12 (ZWP) powder prepared by hydrothermal method was used as fillers to tailor the thermal expansion coefficient (TEC) of the polyimide (PI)-based composites. A series of PI-based composites containing different loading (0-40 wt% or 0-19.6 vol%) of ZWP powder were fabricated by the in-situ polymerization technique. Their structures and properties were characterized by Scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), Impedance meter, Thermal mechanical analysis (TMA) and Thermogravimetric analysis (TGA). The additions of ZWP steadily reduced the TEC of the PI matrix at all loadings studied. A 40 wt% (19.6 vol%) ZWP loading gives a 32.5% (about 15×10 -6 /K) reduction of TEC. The thermal stability of the ZWP/PI composites can be enhanced with the increment of ZWP powder. The independence of the dielectric constant on frequency is improved by introduction of ZWP particles to PIs. The dielectric loss displays good stability, which indicates that the ZWP/PI composites 2 show potential applications in microelectronic and aerospace industries.