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Using different molecular weight of PDADMAC as template, Hβ zeolites and NiMoC/Hβ-Mx catalysts were successfully prepared. The textural properties, acidity and active metal dispersion of samples were characterized by XRD, N2 adsorption and desorption, NH3-TPD, Py-FTIR, H2-TPR, XPS, HRTEM characterizations, to have a better understanding of the importance of PDADMAC molecular weight role. Hydrogenation of model compounds, including naphthalene and quinoline, and real oils were performed on a fixed bed to evaluate the NiMoC/Hβ-Mx catalysts aromatics hydrogenation performance. By analyzing the collected liquid and gas products, it was found that the NMCH-M3 catalyst with PDADMAC molecular weight of 400,000–500,000 exhibited excellent hydrogenation performance in both model compounds and real oils. The mesopore diameter of NiMoC/Hβ-Mx catalysts has great effect on hydrogenation of real oils where the larger pore size is favorable for the hydrogenation reaction. Meanwhile, the B/L ratio of total acid sites and strong acid sites have great effect on aromatics hydrogenation.

Time irreversibility is one of the most important properties of nonstationary time series. Complex time series often demonstrate even multiscale time irreversibility, such that not only the original but also coarse-grained time series are asymmetric over a wide range of scales. We study the multiscale time irreversibility of time series. In this paper, we develop a method called multiscale multifractal time irreversibility analysis (MMRA), which allows us to extend the description of time irreversibility to include the dependence on the segment size and statistical moments. We test the effectiveness of MMRA in detecting multifractality and time irreversibility of time series generated from delayed Henon map and binomial multifractal model. Then we employ our method to the time irreversibility analysis of stock markets in different regions. We find that the emerging market has higher multifractality degree and time irreversibility compared with developed markets. In this sense, the MMRA method may provide new angles in assessing the evolution stage of stock markets.

Three new flavanes and eight known flavonoids were isolated from the fruits of Livistona chinensis. The structure of the new flavanes were established as 2S,3S-3,5,7,3',5'-pentahydroxyflavane (1), 2R,3R-3,5,6,7,8,4'-hexahydroxyflavane (2) and 2R,3R-3,5,6,7,8,3',5'-heptahydroxyflavane (3), respectively, on the basis of chemical and spectroscopic data. The antiproliferative activity against four human tumor cell lines (HL-60, Mata, HepG2 and CNE-1) was evaluated. 1 had significantly antiproliferative effects against HL-60 and CNE-1 with the IC(50) of 0.2 ± 0.01 and 1.0 ± 0.1 μM, respectively, overpowering the reference compound in the assay (cisplatin). Most compounds also exhibited potent antioxidant activity.

Since the early evolution of land plants from primitive green algae, flavonoids have played an important role as UV protective pigments in plants. Flavonoids occur in liverworts and mosses, and the first committed step in the flavonoid biosynthesis is catalyzed by chalcone synthase (CHS). Although higher plant CHSs have been extensively studied, little information is available on the enzymes from bryophytes. Here we report the cloning and characterization of CHS from the moss, Physcomitrella patens. Taking advantage of the available P. patens EST sequences, a CHS (PpCHS) was cloned from the gametophores of P. patens, and heterologously expressed in Escherichia coli. PpCHS exhibited similar kinetic properties and substrate preference profile to those of higher plant CHS. p-Coumaroyl-CoA was the most preferred substrate, suggesting that PpCHS is a naringenin chalcone producing CHS. Consistent with the evolutionary position of the moss, phylogenetic analysis placed PpCHS at the base of the plant CHS clade, next to the microorganism CHS-like gene products. Therefore, PpCHS likely represents a modern day version of one of the oldest CHSs that appeared on earth. Further, sequence analysis of the P. patens EST and genome databases revealed the presence of a CHS multigene family in the moss as well as the 3'-end heterogeneity of a CHS gene. Of the 19 putative CHS genes, 10 genes are expressed and have corresponding ESTs in the databases. A possibility of the functional divergence of the multiple CHS genes in the moss is discussed.