Spatial distribution of the difference in glacier surface elevation between the corrected SRTM data and the DEM 1966 of the Tuanjiefeng region.

<p>Spatial distribution of the difference in glacier surface elevation between the corrected SRTM data and the DEM 1966 of the Tuanjiefeng region.</p

Metadata of Landsat satellite images around the Tuanjiefeng region, Qilian Mountain, China.

<p>Metadata of Landsat satellite images around the Tuanjiefeng region, Qilian Mountain, China.</p

The before and after correction average surface elevation differences between the SRTM and the DEM 1966 over the barren terrain of the Tuanjiefeng region.

<p>(a) elevation zone, (b) slope, and (c) aspect.</p

Location of the Tuanjiefeng region in the Qilian Mountains on the northeastern Tibet Plateau, China.

<p>The lower left map is the distribution of glaciers in the region.</p

The average annual changes in glacier area relative to the area measured in 1966 along the altitude zone over the time periods of 1966–1995, 1995–1999, 1999–2006, and 2006–2010 in the Tuanjiefeng region.

<p>(a) is relative change(%), and (b) is absolute change (km²).</p

Changes in lengths of four typical glaciers (m) around Tuanjiefeng region in 1966, 1973, 1995, 2000, 2006, and 2010, respectively.

<p>Changes in lengths of four typical glaciers (m) around Tuanjiefeng region in 1966, 1973, 1995, 2000, 2006, and 2010, respectively.</p

Changes in areas of four typical glaciers (km²) around Tuanjiefeng region in 1966, 1973, 1995, 2000, 2006, and 2010, respectively.

<p>Changes in areas of four typical glaciers (km²) around Tuanjiefeng region in 1966, 1973, 1995, 2000, 2006, and 2010, respectively.</p

Changes in the glacier areas from 1966 to 2010 in the Tuanjiefeng region, Qilian Mountain, China.

<p>Changes in the glacier areas from 1966 to 2010 in the Tuanjiefeng region, Qilian Mountain, China.</p

Nanoscale Observation of Microfibril Swelling and Dissolution in Ionic Liquids

Ionic liquids (ILs) are widely used for biomass pretreatment because of their excellent dissolving capacity. The efficient and economical use of ILs in pretreatment greatly depends on revealing the underlying mechanism of biomass dissolution. Here, we observed that cellulose microfibrils of rice straw swelled in ILs using atomic force microscopy, and the swelling resulted in a decrease in cellulose crystallinity as determined by time-course X-ray diffraction analysis. The swelling of the IL-induced cellulose microfibrils greatly promoted the saccharification efficiency of rice straw. Compared with conventional acid or alkali solutions, strong hydrogen bond interactions between ILs of the appropriate size and polysaccharides resulted in cellulose microfibrils swelling in ILs, which was demonstrated by nuclear magnetic resonance and molecular simulation. Therefore, microfibril swelling is the key step in cellulose dissolution with ILs; effective swelling could accelerate cellulose dissolution and biomass pretreatment. Thus, those results are helpful in understanding the mechanism of lignocellulose dissolution in ILs and developing new ILs for biomass pretreatment

Location and topography of Muztag Ata and Kongur Tagh.

<p>Location and topography of Muztag Ata and Kongur Tagh.</p