Different oxidation treatments on CNTs using diluted 4.0 M H2SO4 solution at room temperature and or at 90℃ reflux conditions were investigated to elucidate the physical and chemical changes occurring on the treated CNTs, which might have significant effects on their performance as catalyst supports in PEM fuel cells. Raman spectroscopy, X-ray diffraction and transmission electron microscope analyses were made for the acid treated CNTs to determine the particle size and distribution of the CNT-supported Pt-Ru nanoparticles. These CNT-supported Pt-based nanoparticles were then employed as anode catalysts in PEMFC to investigate their catalytic activity and single-cell performance towards H2 oxidation. Based on PEMFC performance results, refluxed Pt-Ru/CNT catalysts prepared using CNTs treated at 90℃ for 0.5 h as anode have shown better catalytic activity and PEMFC polarization performance than those of the commercially available Pt-Ru/C catalyst from ETEK and other Pt-Ru/CNT catalysts developed using raw CNT, thus demonstrating the importance of acid treatment in improving and optimizing the surface properties of catalyst support.
The required for Mla12 resistance (RAR1) protein is essential for the plant immune response. In rice, a model monocot species, the function of Oryza sativa RAR1 (OsRAR1) has been little explored. In our current study, we characterized the response of a rice osrar1 T-DNA insertion mutant to infection by Magnaporthe oryzae, the causal agent of rice blast disease. osrar1 mutants displayed reduced resistance compared with wild type rice when inoculated with the normally virulent M. oryzae isolate PO6-6, indicating that OsRAR1 is required for an immune response to this pathogen. We also investigated the function of OsRAR1 in the resistance mechanism mediated by the immune receptor genes Pib and Pi5 that encode nucleotide binding-leucine rich repeat (NB-LRR) proteins. We inoculated progeny from Pib/osrar1 and Pi5/osrar1 heterozygous plants with the avirulent M. oryzae isolates, race 007 and PO6-6, respectively. We found that only Pib-mediated resistance was compromised by the osrar1 mutation and that the introduction of the OsRAR1 cDNA into Pib/osrar1 rescued Pib-mediated resistance. These results indicate that OsRAR1 is required for Pib-mediated resistance but not Pi5-mediated resistance to M. oryzae.
Disease is one of the significant factors to damage for the crop productivity, including rice. Although there are many methods to avoid from several diseases such as chemical pesticides and biological treatments, it has been appreciated that the most economical and environmentally effective method of disease control is application of resistance genes. A survey (Dardick & Ronald, 2006) reported that plant kinome has a small number of non-RD kinase (nRDK) (4-29% of total kinase), all known or predicted pattern recognition receptors (PRRs) fall into the class. We here introduce a strategy to identify rice resistance genes that are probably encoding PRRs. We selected 130 nRDK genes by combinational analysis of QTL and bioinformatics, 61 of rice mutant lines of 130 candidates inoculated by Xanthomonas oryzae pv. oryzae (Xoo) and Magnaporthe grisea. (M. grisea), and disease progression was monitored. Lesion lengths of the activation mutant lines for nRDK-08 and nRDK-18 genes reduced more than 34% compared to wild type of rice (Dongjin) and other mutant lines. The nRDK-03 and nRDK-17 gene activation rice line had remarkably smaller lesion lengths by M. grisea infection. Our results suggest that a reverse genetic approach using bioinformatics and T-DNA tagging system successfully identified nRDK genes conferring a resistance against Xoo and M. grisea.