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The large, newly discovered Lijiagou pegmatite spodumene deposit, is located southeast of the Ke'eryin pegmatite ore field, in the central Songpan-Garze Fold Belt (SGFB), Eastern Tibet. The Lijiagou albite spodumene pegmatites are unzoned, granite-pegmatites of the subtype LCT (Lithium, Cesium, and Tantalum) and consist of medium- to coarse-grained spodumene, lepidolite, microcline, albite, quartz, muscovite, and accessory amounts of beryl, cassiterite, columbite-tantalite and zircon. Secondary fluid inclusions in quartz and spodumene include two-phase aqueous inclusions (V + L), mono-phase vapor inclusions (V); three-phase CO2-rich CO2-H2O inclusions (CO2 + V + L) and less abundant liquid inclusions (L). The homogenization temperature of the fluid inclusions are low (257.3 to 204.3°C in early stage, 250.3 to 199.6°C in middle stage, 218.7 to 200.6°C in late stage). Fluid inclusions were formed during the long cooling period from the temperature of the pegmatite emplacement. Liquid-vapor-gas boiling was extensive during the middle and late stages. The salinity of the corresponding stages are 15.4 to 13.0 wt.% NaCl equiv., 12.5 to 9.1 wt.% NaCl equiv. and 9.8 to 7.8 wt.% NaCl equiv., respectively. δ18O values of fluid are 7.2 to 5.2‰, 5.6 to 3.9‰ and 2.7 to −0.2‰ from early to late stages; and δD range from −75.1 to −76.8‰, −59.0 to −73.5‰ and −61.6 to −85.5‰ respectively. The δ13C of CO2 values are −5.6 to −6.6‰, −8.5 to −19.9‰, −11.8 to −18.7‰ from early to late stages, suggesting that CO2 in the fluids were probably sourced from a magmatic system, possibly with some mixing of CO2 dissolved in groundwater. δD and δ18O values of fluid indicate that the fluids were originally magmatic water and mixed with some meteoric water in late stage. The magma evolution sequence in the Ke'eryin orefield, from the central two-mica granite through the Lijiagou deposit out to the distal pegmatites, with the ages gradually decreasing, indicates that the Ke'eryin complex rocks are the product of multistage magmatic activity. The large Lijiagou spodumene deposit is a typical magmatic, fractional crystallization related pegmatite deposit. [ABSTRACT FROM AUTHOR]

ABSTRACT Poly( l-lactic acid) (PLA) is now a very attractive polymer for food packaging applications. In this study, PLA/poly(trimethylene carbonate) (PTMC)/talc composite films were prepared by solvent casting. The influence of the talc loading (0, 1, 2, and 3 wt %) on the phase morphology of the PLA/PTMC/talc composites and the improvement in the resulting properties are reported in this article. The scanning electron microscopy images of the composite films demonstrated good compatibility between the PLA and PTMC, whereas talc was not thoroughly distributed in the PLA matrix at talc contents exceeding 3 wt %. The tensile strength and elongation at break of the composite films significantly improved ( p < 0.05). On the contrary, the water vapor permeability and oxygen properties of the composite films decreased by 24.7 and 39.2%, respectively, at the 2 wt % talc loading. Differential scanning calorimetry showed that the crystallinity of the PLA phase increased with the presence of talc filler in the PLA/PTMC/talc composites. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014, 131, 40016. [ABSTRACT FROM AUTHOR]