We investigated the fine-scale genetic structure of three tropical-rainforest trees, Hopea dryobalanoides, Shorea parvifolia and S. acuminata (Dipterocarpaceae), in Peninsular Malaysia, all of which cooccurred within a 6-ha plot in Pasoh Forest Reserve. A significant genetic structure was found in H. dryobalanoides, weaker (but still significant) genetic structure in S. parvifolia and nonsignificant structure in S. acuminata. Seeds of all three species are wind dispersed, and their flowers are thought to be insect pollinated. The most obvious difference among these species is their height: S. parvifolia and S. acuminata are canopy species, whereas H. dryobalanoides is a subcanopy species. Clear differences were also found among these species in their range of seed dispersal, which depends on the height of the release point; so taller trees disperse their seed more extensively. The estimates of seed dispersal area were consistent with the degree of genetic structure found in the three species. Therefore, tree height probably had a strong influence on the fine-scale genetic structure of the three species.
Several multi-walled carbon nanotubes supported Ni-Ce catalysts were synthesized, and their performance in carbon dioxide reforming of methane (CDRM) for syngas production was evaluated. The attachment of Ni-Ce nanoparticles to the functionalized carbon nanotube (fCNT) support was carried out using four synthesis routes, i.e., impregnation (I), sol-gel (S), co-precipitation (C), and hydrothermal (H) methods. Results indicated that synthesis method influences the properties of the NiCe/fCNT catalysts in terms of homogeneity of metal dispersion, size of crystallites, and metal-support interaction. The activity of the catalysts followed the order of NiCe/fCNT(H) > NiCe/fCNT(S) > NiCe/fCNT(C) > NiCe/fCNT(I). The NiCe/fCNT(H) catalyst exhibited the highest catalytic activity with CH4 and CO2 conversions of 92 and 96%, respectively, and resulted in syngas product with consistent H2/CO ratio of 0.91 at reaction temperature of 800 °C without notable deactivation up to 30 h of reaction. Moreover, the growth of carbon on the spent catalyst was only 2% with deposition rate of 4.08 mg/gcat·h; this was plausibly due to the well-dispersed distribution of nanoparticles on fCNT surface and abundant presence of oxygenated groups on the catalyst surface.