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The root powder of Stellera chamaejasme was extracted with petroleum ether. The crude extract obtained was chromatographed repeatedly with silica gel columns. One pure natural product was obtained, which was identified as 5-isopropyl-2-methylphenol (carvacrol), separated for the first time from the root of S. chamaejasme. The results of a laboratory bioassay showed that it had good insecticidal activity against Aphis craccivora and Leucania separata. Its median lethal concentrations (LC(50)) (24 h after treatment) were 16.8 and 12.7 mg L(-1), respectively. This is the first report of the insecticidal activity of carvacrol against A. craccivora and L. separata.

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This paper investigates spatial competition and spatial interdependence in two key strategic variables in franchising: the proportion of franchised outlets (franchise proportion) and the royalty rate. Employing a simultaneous equations model and data from 353 U.S.franchise chains in 43 sectors in 2005, we find robust evidence for significant spatial competition and stable interdependence in these two strategic variables. Specifically, we find spatial competition in each strategic variable, and spatial interdependence between the two strategic variables. Each strategic variable and its spatial lag are strategic complements in spatial competition due to the market share effect, while the two strategic variables are strategic substitutes in spatial interdependence due to the market power effect, and the former effect is stronger than the latter effect. Besides, we also find that franchisors are strongly inclined to a combination of a low royalty rate and a high franchise proportion, which evolves and stabilizes in the long-run equilibrium. These findings provide a consistent framework with which to explain many stylized facts in franchising, such as the time-invariance of a uniform royalty rate, the stability of a mixed organizational structure, and the co-existence of head-on competition and diversification of chains of different sizes. JLE Classification: L1, L2

At present, TiO2 is one of the most widely used photocatalytic materials. However, the narrow response range to light limits the photocatalytic performance. Herein, we reported a successful construction of self-doped R-WO3/R-TiO2/CC nanocomposites on flexible carbon cloth (CC) via electrochemical reduction to increase the oxygen vacancies (Ovs), resulting in an enhanced separation efficiency of photo-induced charge carriers. The photocurrent of R-WO3/R-TiO2/CC at −1.6 V (vs. SCE) was 2.6 times higher than that of WO3/TiO2/CC, which suggested that Ovs could improve the response to sunlight. Moreover, the photocatalytic activity of R-WO3/TiO2/CC was explored using methylene blue (MB). The degradation rate of MB could reach 68%, which was 1.3 times and 3.8 times higher than that of WO3/TiO2/CC and TiO2/CC, respectively. Furthermore, the solution resistance and charge transfer resistance of R-WO3/R-TiO2/CC were obviously decreased. Therefore, the electrochemical reduction of nanomaterials enabled a promoted separation of photogenerated electron–hole pairs, leading to high photocatalytic activity.