This paper aims to understand the pyrolysis and gasification behavior of different Chinese coal samples at different pressures. First, the pyrolysis of four typical Chinese coals samples (Xiaolongtan brown coal, Shenfu bituminous coal, Pingzhai anthracite coal, and Heshan lean coal) were carried out using a pressurized thermogravimetric analyzer at ambient pressure and 3 MPa, respectively. The surface structure and elemental component of the resultant char were measured with an automated gas adsorption apparatus and element analyzer. It was observed that higher pressure suppressed the primary pyrolysis, while the secondary pyrolysis of coal particles was promoted. With respect to the resultant solid char, the carbon content increased while H content decreased; however, the pore structure varied greatly with increasing pressure for different coal samples. For Xiaolongtan brown coal (XLT) char, it decreased greatly, while it increased obviously for the other three char types. Then, the isothermal gasification behavior of solid char particles was investigated using an ambient thermal analyzer with CO 2 as the gasifying agent at 1000 °C. The gasification reactivity of solid char was decreased greatly with increasing pyrolysis pressure. However, the extent of change displayed a vital relation with the characteristics of the original coal sample.

2009) Synthesis and mesomorphic behaviour of new 5-substituted 4-(thien-2-yl)phenyl benzoates, Liquid Crystals, 36:1, 61-66, 4-(5-Alkylthien-2-yl)phenyl 4-alkoxybenzoates and 4-(5-cyanothien-2-yl)phenyl 4-alkoxbenzoates are synthesised by using Pd (0) catalysed coupling reactions as key steps. The thermotropic liquid crystalline behaviour of these compounds is investigated using polarised optical microscopy (POM) and differential scanning calorimetry (DSC). Broad temperature ranges of nematic and/or smectic A mesophases are found in these compounds. The influence of the length of the alkoxy chains and molecular polarisability on the mesophase behaviours is discussed.

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Novel rod like phenylene thiophene based polyhydroxy amphiphiles, derivatives of gallic acid combining three hydrophilic 2,3-dihydroxypropyloxy groups and one alkyl chain via central aromatic linking units, have been synthesized by using Ni(II), Pd(0) catalyzed coupling reaction as key steps. The mesophase behavior of such compounds was investigated by POM and DSC. Thereby the influence of the position of the alkyl chains on the mesophase behavior was discussed. All such compounds exhibit smectic A phases. As the alkyl chain moving from the terminal position to the lateral position near the central of the rigid core, the stability of the smectic A phase would be decreased.