A new polymerizable imidazolium salt monomer, 1-(4-vinylbenzyl)-3-methyl-imidazolium chloride ([VBMI]Cl), has been readily synthesized by reaction of 4-vinylbenzyl chloride with 1-methylimidazole. Novel anion exchange membranes (AEMs) based on the copolymers of [VBMI]Cl and styrene have been prepared and characterized. Excellent thermostability of the membranes is observed through the thermo-gravimetric analysis (TGA) curves. Water uptake and ion exchange capacity (IEC) of the OH(-) form AEMs range from 26.1% to 61.9% and from 0.95 to 1.45 mmol g(-1), respectively. This type of AEM displays significant ionic conductivities over the order of 10(-2) S cm(-1) in deionized water at room temperature, and the membranes are stable in 10 mol L(-1) NaOH solution at 60 degrees C for 120 h. For the H(2)/air single fuel cell at 30 degrees C with this novel AEM, the peak power density of 33 mW cm(-2) is obtained at a current density of 59 mA cm(-2).High-Tech Research and Development Program of China[2008AA05Z107]; National Nature Science Foundation of China[20876129

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This paper researches the compatibility of bamboo and Portland cement by measuring the hydration temperature of Portland cement. Meanwhile, bamboo shavings and Portland cement, which were utilized as main raw materials, were prepared into bamboo Portland cement particle boards through cold compression forming, so as to further verify the compatibility of bamboo and Portland cement and research the practicability of preparing bamboo Portland cement particle boards by using bamboo. Research studies show that bamboo contain water-soluble saccharides, such as polysaccharide, disaccharide, and glucose, and organic carboxylic acids, such as formic acid and acetic acid. Water-soluble saccharides are converted into saccharic acid after dissolving in water, then a saccharide–calcium complex with a pompon-like structure is formed through a reaction between saccharic acid and calcium ions of Portland cement hydrates, and the saccharide–calcium complex covers the surfaces of the cement particles and prevents further hydration of the cement, achieving a certain anticoagulation effect on Portland cement; a chelation reaction between the carboxyl of the organic carboxylic acid and the calcium ions of Portland cement hydrates takes place and the concentration of calcium ions in the hydration system is reduced, which exerts an influence on further hydration process of Portland cement and achieves a certain anticoagulation effect. Because of the poor compatibility of Portland cement and bamboo, the physical and mechanical properties of bamboo Portland cement particle boards prepared from bamboo shavings and Portland cement directly cannot meet the requirements of the national standards (GB/T24312-2009) of cement particle boards.

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