We have designed a new hypercrosslinked supermicroporous polymer (HMP-1) with a BET surface area of 913 m(2) g(-1) by FeCl3 via a catalyzed Friedel-Crafts alkylation reaction between carbazole and α,α'-dibromo-p-xylene. Upon sulfonation HMP-1 yielded a very efficient solid acid catalyst for the production of biodiesels via esterification/transesterification of free fatty acids (FFA)/esters at r...

The tensile properties of sulfonated polyoxadiazoles have been studied as a function of molecular weight and sulfonation level. All sulfonated polyoxadiazoles synthesized through a polycondensation reaction of the hydrazine sulphate salt and a dicarboxylic acid in poly(phosphoric acid) exhibit rigid-ductile behavior with high Young’s modulus (3-4 GPa) and with larger elongations at break (up to...

a type of novel hypercross-linked fiber adsorbent was obtained by sulfonation and cross-linking reaction of polypropylene fiber grafted styrene-divinylbenzene. the aim of the fiber sulfonation and cross-linking method was to prepare rigid three dimensional networks in the entire fiber and change the ion exchange capacity of fiber. the hypercross-linked fiber adsorbent possesses a principally di...

Brassinosteroids represent a class of plant hormones. More than 70 compounds have been isolated from plants. Currently 42 brassinosteroid metabolites and their conjugates are known. This review describes the miscellaneous metabolic pathways of brassinosteroids in plants. There are some types of metabolic processes involving brassinosteroids in plants: dehydrogenation, demethylation, epimerizati...

Direct liquid-phase sulfonation of methane to methanesulfonic acid (MSA) with SO2 has been achieved in triflic acid using K2S2O8 as the oxidant and a small amount of a Ca salt as the promoter. The effects of reaction conditions on the conversion of SO2 to MSA were examined. Included were the influence of solvent acidity, reaction duration, reaction temperature, amount of K2S2O8, and composition...

It has been drawn to the attention of the authors that in Figure 1 the common intermediate products of the transformation of progesterone and 5,16 androstadien-3bol into androstenone is 4,16-androstadien-3-ene (and not 4,16 androstadien-3-one). In addition, the list of the final products of androstenone sulfonation has been completed. This corrigendum published in issue 5, 2008 is freely availa...

      The muscle-like technology would be of enormous advantages for biomedical applications such as medical implants and human assist devices. Ionic polymer metal composites (IPMCs) are one kind of biomimetic actuators. An ionic polymer metal composite composed from an ionomer with high ion exchange capacity that packed between two thin metal layers. In the present study we focused on the prep...