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We attempted to study the immune response in M. rosenbergii by melanization reaction produced by plasma phenoloxidase (PO) activity. The substrate affinity of the PO enzyme was determined using different phenolic substrates, and it was found that the diphenols were only oxidized. The enzyme was characterized as catechol oxidase type of PO and L-3,4 dihydroxyphenylalanine (L-DOPA) showed the highest substrate affinity to the enzyme. The biochemical parameters that determined optimum enzyme activity were found to be 2.5 mM L-DOPA at an absorbance of 470 nm, 10 mM Tris–HCl buffer at pH 7.5, temperature at 25°C, and 15 min incubation. Kinetic characteristics of plasma were studied from the M. rosenbergii. The hemocyanin was isolated by gel filtration chromatographic technique using Sephadex G-100. The M. rosenbergii hemocyanin (MrHC) showed only one band with a molecular weight of 325 kDa on native polyacrylamide gel electrophoresis (PAGE) when stained with Coomassie Brilliant Blue (CBB) and bathocuproine sulfonic acid. The reduction of MrHC protein in SDS-PAGE displayed three subunits with a molecular weight of 74, 76, and 78 kDa, respectively. Determination of optimal condition for PO activity of plasma has also been attempted. The plasma optimal condition taken for the MrHC was tested for its ability to oxidize diphenols such as L-DOPA was shown only PO activity. These results showed that in the presence of PO and peroxidase inhibitors, phenylthiourea (PTU) and tropolone respectively have decreased plasma and MrHC PO activity. This indicates that hemocyanin triggers innate immunity probably through one of its subunits that function as the active moiety.

To the first time, thermal conductivities of spark plasma sintered β-sialons (Si3Al3O3N5) procured from combustion synthesis (CS) with no sintering additive were measured by the laser flash method at room temperature. A full densification occurred when these materials were sintered at 1600 °C with a simultaneous pressure of 50 MPa. XRD analyses indicated that single phase β-sialons were formed after SPS though the combustion synthesized β-sialon powders had considerable amounts of silicon impurities. Thermal conductivity values increased with sintering temperature and attained a maximum of 5.49 W m−1 K−1 for fully densified β-sialons sintered at 1700 °C for 10 min.

Fully dense multiwall carbon nanotubes (MWCNT)/SiO2 nanocomposites with MWCNTs contents of 5 and 10 vol% have been processed by spark plasma sintering, and the electrical conductivities of the nanocomposites were evaluated at temperatures ranging from 5 to 300 K. It has been found that the incorporation of MWCNTs converted an insulating silica nanoceramic into metallically conductive composites. The room-temperature conductivities of the nanocomposites, with over 14 orders of magnitude compared with pure silica, are in the range of 8 and 65 S/m. Also, it was interestingly found that the conductivity increased linearly with temperature from 5 to 300 K.

The influence of diluent addition on purities of β-Si5AlON7 powders synthesized by mechanically activated combustion synthesis (MA-CS) under a very low nitrogen atmosphere of 1 MPa was investigated. The purity of β-Si5AlON7 powders increased with diluent concentrations in raw materials and had a maximum value of 91% when 40 mass% of diluents were added, a 25% more pure when compared to powders procured without diluents. In contrast, when diluents were included 50% or more, the combustion synthesis (CS) reaction did not occur due to reduced exothermic heat. The results also showed that the particle sizes of β-Si5AlON7 powders synthesized with 40 mass% of diluents were only one-tenth when compared to powders synthesized without diluents.

Fine β-sialon (Si6−zAlzOzN8−z, 1