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Constructing advanced anode materials with suitable operational potential and high energy density toward metal ion batteries is of significance for next-generation batteries. Carbon-coated porous Sb 2 Te 3 nanoplates with high density and suitable operational potential, prepared by a hydrothermal and carbonization technique, manifest good electrochemical performance, including excellent rate capability, high capacities, and outstanding cycling performance. This performance can be traced to its special structure, including porous Sb 2 Te 3 and the shell of carbon, which can provide fast charge transfer paths and maintain the structural stability for the entire material. The proposed strategy here of embedding porous high-density anode material in twodimensional carbon provides a new avenue for designing anode materials with excellent gravimetric and volumetric capacities toward superior energy storage. KEYWORDS: volumetric capacity, porous Sb 2 Te 3 @C, lithium ion batteries, Sb 2 Te 3 , sodium ion batteries, nanoplates

Melodinus is an important genus comprising of approximately 53 species of medicinal plants (Apocynaceae). Some species have been used in Chinese folk medicine for the treatment of meningitis in children, rheumatic heart diseases, and diuresis, as well as a decongestive against migraine and sinusitis. This paper is a review of the literature up to May 2015 and describes 263 compounds from 69 articles, and includes chemical constituents isolated from Melodinus, mainly indole alkaloids, quinoline alkaloids, dimeric alkaloids, terpenoids and other compounds. It is also hoped that an overview of their cytotoxic characteristics will further the development of new anti-cancer agents.

Methyl laurate was synthesized from lauric acid (LA) and methanol via an esterification reaction using ionic liquids (ILs) as catalysts. The efficiencies of three different catalysts, 1-methylimidazole hydrogen sulfate ([Hmim]HSO4), 1-methyl-2-pyrrolidonium hydrogen sulfate ([Hnmp]HSO4) and H2SO4, were compared. The effect of the methanol/LA molar ratio, reaction temperature, reaction time and catalyst dosage on the esterification rate of LA was investigated by single-factor experiments. Based on the single-factor experiments, the esterification of LA and methanol was optimized using response surface methodology. The results showed that the most effective catalyst was the IL [Hnmp]HSO4. The optimal conditions were as follows: [Hnmp]HSO4 dosage of 5.23%, methanol/LA molar ratio of 7.68 : 1, reaction time of 2.27 h and reaction temperature of 70°C. Under these conditions, the LA conversion of the esterification reached 98.58%. A kinetic study indicated that the esterification was a second-order reaction with an activation energy and a frequency factor of 68.45 kJ mol−1 and 1.9189 × 109 min−1, respectively. The catalytic activity of [Hnmp]HSO4 remained high after five cycles.