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Hybridization is one of the negative outcomes for the introduction of non-native species, which can lead to rapid displacement and genetic extinction of native species. Salmonid fishes have been widely introduced outside of their native ranges for food supply and recreational fishing. Here, we investigate the occurrence of introgressive hybridization among native Dolly Varden (Salvelinus curilus (syn. Salvelinus malma)), white-spotted charr (Salvelinus leucomaenis), and introduced brook trout (Salvelinus fontinalis), in streams of the Nishibetsu River, Hokkaido, Japan. Microsatellite DNA analysis detected five hybrids between native Dolly Varden and introduced brook trout. This is the first evidence for hybridization between native Dolly Varden and introduced brook trout, while the latter has been known to hybridize with many other salmonids. Furthermore, incongruence between mitochondrial DNA and microsatellite DNA analyses suggested introgression among the three Salvelinus species. Further studies to estimate the hybrid fitness are necessary to understand how hybridization among the three species affects the native species.

Hybridization is one of the negative outcomes for the introduction of non-native species, which can lead to rapid displacement and genetic extinction of native species. Salmonid fishes have been widely introduced outside of their native ranges for food supply and recreational fishing. Here, we investigate the occurrence of introgressive hybridization among native Dolly Varden (

In this study, the low-temperature synthesis of rhodium phosphide (Rh2P) on alumina (Al2O3) using triphenylphosphine (TPP) as a phosphorus (P) source and its catalytic activity toward hydrodesulfurization (HDS) were investigated to prepare a highly active HDS catalyst. TPP was more easily reduced than phosphate, and Rh2P was formed in the P(T)/Rh/Al2O3 catalyst prepared from TTP at lower temperature as compared with the temperature required by Rh-P(A)/Al2O3 catalyst prepared from a phosphate precursor. However, after reduction at a low temperature (450 °C), excess P covered the surface of Rh2P. The optimal reduction temperature for HDS rate of the P(T)/Rh/Al2O3 catalyst (650 °C) was lower than that of the Rh-P(A)/Al2O3 catalyst (800 °C). Furthermore, this temperature was slightly higher than the optimal reduction temperature for CO uptake (600 °C). These results are explained as follows: HDS rate is increased by both elimination of excess P on the active sites at higher reduction temperatures and enhancement of the crystallinity of Rh2P. Furthermore, because the particle size of the P(T)/Rh/Al2O3 catalyst (ca. 1.2 nm) was substantially smaller than that of the Rh-P(A)/Al2O3 catalyst, the P(T)/Rh/Al2O3 catalyst exhibited greater HDS rate compared with the Rh-P(A)/Al2O3 catalyst.

[10]Cycloparaphenylene ([10]CPP) and its tetraalkoxy derivatives were synthesized on the gram scale in 7 steps starting from 1,4-benzoquinone or 2,5-dialkoxy-1,4-benzoquinone. The key steps involve the highly cis-selective bis-addition of 4-bromo-4′-lithiobiphenyl to the quinones to produce a five-ring unit containing cyclohexa-1,4-diene-3,6-diol moiety, the platinum-mediated dimerization of the five-ring unit, and the H2SnCl4-mediated reductive aromatization of cyclohexadienediol. The tetraalkoxy substituents increased the solubility of [10]CPP in common organic solvents. The carrier-transport properties of thin films of [10]CPP and its derivatives were measured for the first time and indicated that [10]CPP derivatives could rival phenyl-C61-butyric acid methyl ester, which is used widely as an n-type active layer in bulk heterojunction photovoltaics.

Effect of sodium (Na) addition on rhodium phosphide (Rh2P) formation on MFI zeolite, SiO2 and Al2O3 and hydrodesulfurization (HDS) activity were examined. The TPR results revealed that Na addition enhanced reducibility of phosphates. The XRD results indicated that Rh2P phase was easily formed on NaMFI support as compared with on HMFI support. The maximum HDS activity of Rh–P/NaMFI catalyst was obtained at lower reduction temperature and this activity was higher than that of Rh–P/HMFI catalyst. We concluded that since Na would weaken interaction between Al and phosphate, high HDS activity of Rh–P/NaMFI catalyst was observed at lower reduction temperature.

Effects of reduction temperature and phosphorus loading on rhodium phosphide (Rh 2 P) formation and on the catalytic activity of Rh- x P catalysts for hydrodesulfurization (HDS) were investigated to prepare highly active HDS catalysts. Analysis of the Rh- x P catalysts showed that a suitable P loading for HDS activity is 1.5 wt%—four times greater than that of an Rh catalyst. Temperature-programmed reduction and X-ray diffraction analyses of the Rh- x P catalysts showed that Rh 2 P is readily formed in catalysts with higher P loading. In contrast, the results of transmission electron microscopy observation and CO adsorption experiments indicated that the Rh 2 P particle size increased with increasing P content. Thus, the high HDS activity of the Rh-1.5P catalyst was explained by the formation of small Rh 2 P at a relatively low reduction temperature (550 °C).

The effect of precursors on the active phase formation and hydrodesulfurization activities of noble metal phosphide catalysts was examined. The maximum activities of Pd–P and Rh–P catalysts prepare...