The present study is to understand the impact of process conditions on the quality attributes of wheat oat, barley, and canola straw briquettes. Analysis of variance indicated that briquette moisture content and initial density immediately after compaction and final density after 2 weeks of storage are strong functions of feedstock moisture content and compression pressure, whereas durability rating is influenced by die temperature and feedstock moisture content. Briquettes produced at a low feedstock moisture content of 9 % (w.b.) yielded maximum densities >700 kg/m 3 for wheat, oat, canola, and barley straws. Lower feedstock moisture content of <10 % (w.b.) and higher die temperatures >110°C and compression pressure >10 MPa minimized the briquette moisture content and maximized densities and durability rating based on surface plots observations. Optimal process conditions indicated that a low feedstock moisture content of about 9 % (w.b.), high die temperature of 120-130°C, medium-to-large hammer mill screen sizes of about 24 to 31.75 mm, and low to high compression pressures of 7.5 to 12.5 MPa minimized briquette moisture content to <8 % (w.b.) and maximized density to >700 kg/m 3 . Durability rating >90 % is achievable at higher die temperatures of >123°C, lower to medium feedstock moisture contents of 9 to 12 % (w.b.), low to high compression pressures of 7.5 to 12.5 MPa, and large hammer mill screen size of 31.75 mm, except for canola where a lower compression pressure of 7.5 to 8.5 MPa and a smaller hammer mill screen size of 19 mm for oat maximized the durability rating values.

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This study investigated the relationship between vegetation coverage, species richness, and environmental factors, and also analyzed the relationship between vegetation coverage, species richness, and dune stability in different terrains, in the southern part of Gurbantu¨nggu¨t Desert in China. The results showed that the order of vegetation coverage and species richness was greatest in middle areas, followed by the eastern areas, with the western areas being sparse. On a large scale, precipitation from April to June determined the amount of vegetation coverage. On a small scale, vegetation coverage was influenced by the type of terrain and the water and salt content in soils. Species richness of vegetation was determined by soil water and salt content on both the large and small scales. There were also remarkable differences in relative wind erosion among the different terrains and their order was: crest, slope, and inter-dune in descending order. The correlations between wind erosion and vegetation coverage and species richness were influenced by the type of terrain. Furthermore, there were significant correlations between wind erosion and vegetation coverage and species richness in dune slopes and crests. There was, however, no significant correlation between wind erosion and vegetation coverage and species richness in inter-dune sites. Vegetation coverage was the dominant factor influencing wind erosion in both slopes and crests. Species richness may have an impact on wind erosion through vegetation coverage in both slopes and crests. These results suggest that the effect of terrain type should be fully considered during the establishment of vegetation cover in the desert.

Hierarchical porous carbon spheres (PCSs) with a tunable pore structure were prepared from larch sawdust via spray pyrolysis and a soft-templating method. Decomposition of the soft template, i.e., Pluronic F127, in the carbonization step led to formation of a hierarchical porous structure with mesopores and macropores. Swelling of the core, presumably predominantly of the poly(propylene oxide) component, was induced by evaporation of water. This led to the generation of ultra-large mesopores and macropores. The surface morphology and pore structure of the carbon spheres were controlled by varying the F127 concentration. The PCSs morphologies changed from smooth to rough with increasing addition of F127, and the particle sizes became more uniform. When the content of F127 reached 0.075 (ratio of F127/ larch-based resin), the prepared PCSs (PCSs-0.075) had structural integrity, a high surface area (760.3 m 2 g −1 ), and a large pore volume (0.59 cm 3 g −1 ), and contained a combination of micropores, macropores, and mesopores. X-ray diffraction and Raman spectroscopy showed that addition of F127 had little effect on the graphitic degree of the samples. Because of its hierarchical pore structure and high surface area, the optimized sample, i.e., PCSs-0.075, gave an excellent electrochemical performance as an electrode material for supercapacitors, with a specific capacitance of 338.8 F g −1 at 0.2 A g −1 and a good rate capability (165.1 F g −1 at 5 A g −1 ) in 6 M KOH solution. These PCSs with mesopores and macropores, which facilitate penetration of ions into pores, are promising as efficient electrode materials for supercapacitors.