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Three new arylbenzofurans, 7-methoxy-2-(4-methoxyphenyl)-3-methyl-5-(3-prenyl)-benzofuran ( 1 ), 2-(4-methoxyphenyl)-3-methyl-5-(3-prenyl)-benzofuran-7-ol ( 2 ), 2-(4-hydroxy-3,5-dimethoxyphenyl)-3-methyl-5-(3-prenyl)benzofuran-7-ol ( 3 ), along with four known arylbenzofurans ( 4 – 7 ) were isolated from the fermentation products of an endophytic Phomopsis sp. Their structures were elucidated by spectroscopic methods including extensive 1D- and 2D-NMR techniques. In addition, compounds 1 – 7 were tested for their anti-tobacco mosaic virus (anti-TMV) activity. The results showed that compound 3 exhibited obvious anti-TMV activity with inhibition rate of 35.2% better than that of positive control (31.8%). The other compounds also showed potential anti-TMV activity with inhibition rates in the range of 18.6–25.7%, respectively. [ABSTRACT FROM AUTHOR]

Abstract: In order to improve the electrochemical cycle stability of La–Mg–Ni system (PuNi3-type) hydrogen storage alloy, a trace of Cr was added in the alloy and La2Mg(Ni0.85Co0.15)9Cr x (x =0, 0.1, 0.2, 0.3, 0.4) hydrogen storage alloys were prepared by casting and rapid quenching. The effects of Cr addition on the microstructures and electrochemical performances of the as-cast and quenched alloys were investigated in detail. The obtained results show that Cr addition engenders an inappreciable influence on the phase composition of the as-cast and quenched alloys, but it changes the phase abundance of the alloys significant. The Cr addition markedly enhances the cycle stability of the as-cast and quenched alloys, but it decreases the discharge capacity. When Cr content increased from 0 to 0.4, the discharge capacity of the as-cast alloy decreased from 396.3 to 355.6mAh/g, and the cycle life prolonged from 72 to 97 cycles. For the as-quenched (30m/s) alloys, the discharge capacity reduced from 364.2 to 334.2mAh/g, and the cycle life extended from 100 to 131 cycles. [Copyright &y& Elsevier]

In order to further reduce the cost of AB5 type rare-earth-based hydrogen storage alloy, a low-Co AB5 type hydrogen storage alloy was prepared by substituting Cr, Si, Cu for Co and adjusting of the composition. The result showed that the effect of the three kinds of substituting elements on cycle life increased in the sequence Si>Cr>Cu; and on the discharge capacity in the sequence Cu>Cr>Si. An overall favorable effect becomes possible by adding small quantities of Cr, Cu, Si. The discharge capacity and activation property as well as rate discharge capability of low-Co mischmetal based hydrogen storage electrode alloy reached the requirements of practical use when applying nonstoichiometric compositions. [Copyright &y& Elsevier]

In order to improve the electrochemical characteristics of AB2 Laves phase electrode alloys, the rapid quenching technology was used in the preparation of AB2 type Ti- and Ti-Zr-based electrode alloys. The effects of the rapid quenching on the electrochemical characteristics and microstructures of AB2 Laves phase electrode alloys were investigated comprehensively. The experimental results showed that the effects of the rapid quenching on the electrochemical properties and microstructures of AB2 Laves phase electrode alloys were closely relevant with the compositions of the alloys. For Ti-based alloy, the capacity of the as-quenched alloy was enhanced obviously with the increase of the quenching rate, and a maximum capacity could be obtained at a certain quenching rate. The rapid quenching had little effect on the activation capability and improved the cycle stability slightly. For Ti-Zr-based alloy, the cycle stability was exalted significantly and the capacity and activation capability were reduced dramatically with the increase of the quenching rate. The main reason why the rapid quenching can modify the electrochemical performances of AB2 Laves phase electrode alloys was that it has obviously changed the microstructures of the alloys. [Copyright &y& Elsevier]

Low Co AB5-type MmNi3.8Co0.4Mn0.6Al0.2Bx (x=0, 0.1, 0.2, 0.3, 0.4) hydrogen storage alloys were prepared by cast and rapid quenching. The microstructures and electrochemical performances of the as-cast and quenched alloys were analysed and measured. The effects of boron additive and rapid quenching technique on the microstructures and electrochemical properties of as-cast and quenched alloys were investigated comprehensively. The experimental results showed that the microstructure of as-cast MmNi3.8Co0.4Mn0.6Al0.2Bx (x=0, 0.1, 0.2, 0.3, 0.4) alloys was composed of CaCu5-type main phase and a small amount of CeCo4B-type secondary phase. The abundance of the secondary phase increases with the increase of boron context x. The rapid quenching techniques were used in the preparation of the alloys. The amount of secondary phase in the alloys decreased with the increase of quenching rate. Rapid quenching made lattice constants increase slightly. The effects of rapid quenching on the electrochemical performances of the alloys are very significant. The discharge capacity of the alloys decreased obviously and the cycle stability increased dramatically with the increase of quenching rate. Rapid quenching made the activation capability of the alloys lowered. However, the activate performance and high rate discharge capability as well as discharge voltage characteristic of the alloys were modified obviously with the increase of boron content x. [Copyright &y& Elsevier]