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2-hydroxy-N-(2-hydroxyethyl)-N-methylethanaminium methanesulfonate ([BHEM][mesy]) displayed good ability for separating cellulose from biomass material in previous works. In order to have a better understanding of the structure–property relationship and facilitate further potential applications in industry, it is necessary to obtain more data for the physicochemical properties of [BHEM][mesy] and its mixtures. In this work, the densities (ρ) and viscosities (η) of [BHEM][mesy] + solvents (water, methanol, ethanol, n-propanol and isopropanol) mixtures were measured at six temperatures from (298.15 to 323.15) K over the full molar composition range and fitted by an empirical quadratic equation and Vogel–Fucher–Tammann (VFT) equation. Moreover, the excess molar volumes (VE) and viscosity deviation (Δη) of five binary mixtures were calculated and correlated by the Redlich–Kister equation. In addition, the apparent molar volumes ($${V}_{\varphi }$$) and partial molar volumes ($$\stackrel{-}{V}$$) of [BHEM][mesy] and solvents were also calculated and all these physicochemical property data (density, viscosity, excess molar properties as well as the apparent molar properties) are discussed in terms of the structure and interaction of binary mixtures.

Based on the revised First Chinese Glacier Inventory (FCGI), the Second Chinese Glacier Inventory (SCGI) and Landsat OLI images for 2015–2016, we analyzed the spatial-temporal variation characteristics of glaciers in the Gangdise Mountains from 1970 to 2016. The results showed that there were 3953 glaciers with a total area of 1306.45 km2 and ice volume of ~58.16 km3 in the Gangdise Mountains in 2015–2016. Glaciers with sizes of 0.1–5 km2 and

Bio-gasoline derived from biomass is a clean and renewable energy, which can replace conventional petroleum-derived transport fuels. Here, we developed and evaluated a new catalytic process for the production of a renewable bio-gasoline from corn stover. In this process, corn stover is converted into bio-gasoline via a four-step catalytic conversion: hydrolysis of corn stover to levulinic acid (LA), dehydration of LA to angelica lactone (AL), di-/trimerization of AL to AL dimer and trimer and hydrogenation of AL dimer and trimer to bio-gasoline. Techno-economic analysis of a plant with a production capacity of 10,000 t/yr bio-gasoline was performed based on the integrated bio-gasoline production process using corn stover as feedstock. The results indicated that the price of target product as well as raw materials had great influence on this process. The return on investment of this process was estimated to be 15.8%, which maintained a break-even point when this process was operating at only 39% of the designed capacity. The results demonstrated that this technology provided an economically attractive and sustainable pathway in the conversion of waste biomass to bio-gasoline. Schematic of the integrated process for the bio-alkanes production from corn stover

Nanoflower-like ZnO–C3N4 thin film with a porous net structure was successfully synthesized by a simple chemical corrosion method. The prepared ZnO–C3N4 thin films presented remarkable photocatalytic activities for the degradation of methyl orange under visible light irradiation, and more than 90% methyl orange was removed from water by ZnO–C3N4 composite. Meanwhile, the ZnO–C3N4 composite presented an enhanced photocatalytic stability. The loading content of C3N4 had a great effect on the photocatalytic performance. Moreover, the photocatalytic activities were higher in acidic media than those in alkaline conditions. The adsorption of methyl orange was enhanced, and the recombination of photogenerated electrons and holes was suppressed with a suitable content of C3N4. However, too much loading content of C3N4 resulted in a poor dispersion of C3N4 as the aggregated C3N4 can behave as recombination centers. In addition, the prepared ZnO–C3N4 thin film can be used for the water splitting in water–methanol system under simulated solar light irradiation.

A highly stable solvate ionic liquid comprising a 2:1 (mol/mol) mixture of ethylene carbonate (EC) and AlCl3 was used for near room-temperature electrochemical codeposition of an Al-Nd alloy using chlorides as precursors. This liquid is low-cost, easy to prepare, and has high electrochemical stability. The ionic structure was analyzed by 27Al nuclear magnetic resonance; Raman spectroscopy and the dissolution phenomenon was studied by ultraviolet-visible spectroscopy. The dissolution mechanism of NdCl3 in this solvate ionic liquid was derived as 3[AlCl2(EC)n]+ + 2NdCl3 ⇆ 2Nd(III) + 3[AlCl4]− + 3nEC. Cyclic voltammetry was used to explore the electrochemical behavior of Nd- and Al-containing species, revealing that the reduction of Al and Nd are both one-step electron-gaining processes. X-ray diffraction confirmed that an Al-Nd alloy can be obtained in the form of thermally stable Al2Nd by potentiostatic electrolysis at high cathode overpotential (− 3.5 V vs. Al). Although the deposited alloy layer is not dense, Al-containing solvate ILs have immense potential in green electrometallurgy because of their higher tunability and similar properties to ILs.

Zn(II)-doped graphitic carbon nitride (g-C3N4) with high photodegradation activity was prepared by one facile step. The morphology and structure of the prepared Zn(II)-doped g-C3N4 were investigated, and the results showed that Zn(II) could self-disperse during the pyrolysis process and Zn–N bond was formed between g-C3N4 and Zn. The dope of Zn(II) influenced the structure of g-C3N4. The performance of photocatalytic activity of Zn(II)-doped g-C3N4 series indicated that the doped g-C3N4 with a small quantity of Zn (0.10 wt%) exhibits the best photocatalytic performance. The photodegradation activity for methyl orange was 2 times higher than that of pure g-C3N4. However, the photocatalytic activity decreased with the further increased content of Zn, which may be attributed to the structure change of g-C3N4 and the interaction of Zn–N bond between Zn and g-C3N4. Moreover, Zn(II)-doped g-C3N4 showed good recycling photocatalytic stability.

The variation of glacier mass balance during the past decades remains poorly known for Duxueshan, Burog Kangri, and Zangser Kangri (DBZ) which are located in the Inner Tibetan Plateau (ITP), a transition zone with shifting influences between the westerlies and the Indian summer monsoon. In the present study, glacier area and mass changes were determined by topographic maps (TOPO), Landsat imagery and multi-temporal digital elevation models (DEMs) generated with TOPO, SRTM, TanDEM-X bistatic interferometric synthetic aperture radar (InSAR) images, and High Mountain Asia 8-m DEMs. On average, the glaciers showed a slight retreat from 343.27 ± 5.23 km2 in 1971 to 334.67 ± 3.21 km2 in 2018 (0.05 ± 0.04% a−1). However, glaciers lost mass at a rate of -0.32 ± 0.03 m w.e. a−1 from 1971 to 2012. For the 1999–2012 and 2012–2017 periods, mass balances of − 0.03 ± 0.16 and 0.09 ± 0.04 m w.e. a−1, respectively, were observed, which represents an approximately equilibrium. Two glaciers also advanced in our investigation period, and we confirmed one of them surged in 2015.

Separation of cellulose Ι material from biomass with high efficiency by using ionic liquid (IL) is still challenging. In this work, three low-cost polyhydric protic ammonium-salt ILs (about $1000/t) based on sulphonethane anion were synthesized via one-step protonation reaction and firstly applied in the pretreatment of corn straw. After study on the influence of selected process parameters, such as extraction time, extraction temperature and the IL recycling, 2-hydroxy-N-(2-hydroxyethyl)-N-methylethanaminium methanesulfonate ([BHEM]mesy) exhibits the highest efficiency with the content of cellulose up to 90 wt% in the cellulose material obtained at 140 °C for 6 h. Characterization analysis of the cellulose products certified that the cellulose materials maintain the same crystal structure of cellulose I as native corn straw. Gas chromatography–mass spectrometry and mass spectrometry methods were conducted to explore the possible separation mechanism. [BHEM]mesy shows the prospect of industrialization for cellulose I material separation from biomass owing to its low-cost and high-efficiency characteristics.

Glaciers are the most important fresh-water resources in arid and semi-arid regions of western China. According to the Second Chinese Glacier Inventory (SCGI), primarily compiled from Landsat TM/ETM+ images, the Qilian Mountains had 2684 glaciers covering an area of 1597.81±70.30 km2 and an ice volume of ~84.48 km3 from 2005 to 2010. While most glaciers are small (85.66% are 20 km2 in the Qilian Mountains. Median glacier elevation was 4972.7 m and gradually increased from east to west. Glaciers in the Qilian Mountains are distributed in Gansu and Qinghai provinces, which have 1492 glaciers (760.96 km2) and 1192 glaciers (836.85 km2), respectively. The Shule River basin contains the most glaciers in both area and volume. However, the Heihe River, the second largest inland river in China, has the minimum average glacier area. A comparison of glaciers from the SCGI and revised glacier inventory based on topographic maps and aerial photos taken from 1956 to 1983 indicate that all glaciers have receded, which is consistent with other mountain and plateau areas in western China. In the past half-century, the area and volume of glaciers decreased by 420.81 km2 (–20.88%) and 21.63 km3 (–20.26%), respectively. Glaciers with areas

Glaciers in the western Nyainqentanglha Range are an important source of water for social and economic development. Changes in their area were derived from two Chinese glacier inventories; one from the 1970 1:50,000 scale Chinese Topographic Maps series and the other from Landsat TM/ETM+ images acquired in 2009. Analyses also included boundaries from 2000 and 2014 Landsat TM/ETM+ images. A continuing and accelerating shrinkage of glaciers occurred here from 1970 to 2014, with glacier area decreasing by 244.38 ± 29.48 km2 (27.4% ± 3.3%) or 0.62% ± 0.08% a–1. While this is consistent with a changing climate, local topographic parameters, such as altitude, slope, aspect and debris cover, are also important influences. Recession is manifested by a rise in the elevation of the glacier terminus. The shrinkage of glaciers with NE, N and NW orientations exceeded that of other aspects, and glaciers with SE and S orientations experienced less shrinkage. Changes in the average positive difference of glaciation (PDG) show that the western Nyainqentanglha Range has unfavorable conditions for glacier maintenance which is being exacerbated by a warming climate since 1970.

Volcanic rock found in the Longgang Volcano Group in Jilin Province of China has properties essentially similar to Apollo lunar soils and previously prepared lunar soil simulants, such as Johnson Space Center Lunar simulant and Minnesota Lunar simulant. In this study, an electrochemical method of preparation of Al-Si master alloy was investigated in 52.7 wt.%NaF-47.3 wt.%AlF3 melt adding 5 wt.% volcanic rock at 1233 K. The cathodic electrochemical process was studied by cyclic voltammetry, and the results showed that the cathodic reduction of Si(IV) is a two-step reversible diffusion-controlled reaction. Si(IV) is reduced to Si(II) by two electron transfers at −1.05 V versus platinum quasi-reference electrode in 52.7 wt.%NaF-47.3 wt.%AlF3 molten salt adding 5 wt.% volcanic rock, while the reduction peak at −1.18 V was the co-deposition of aluminum and silicon. In addition, the cathodic product obtained by galvanostatic electrolysis for 4 h was analyzed by means of x-ray diffraction, x-ray fluorescence, scanning electron microscopy and energy dispersive spectrometry. The results showed that the phase compositions of the products are Al, Si, Al5FeSi, and Al3.21Si0.47, while the components are 90.5 wt.% aluminum, 4.4 wt.% silicon, 1.9 wt.% iron, and 0.2 wt.% titanium.

Glaciers in the eastern Pamir are important for water resources and the social and economic development of the region. In the last 50 years, these glaciers have shrunk and lost ice mass due to climate change. In order to understand recent glacier dynamics in the region, a new inventory was compiled from Landsat TM/ETM+ images acquired in 2009, free of clouds and with minimal snow cover on the glacierized mountains. The first glacier inventory of the area was also updated by digitizing glacier outlines from topographical maps that had been modified and verified using aerial photographs. Total glacier area decreased by 10.8%±1.1%, mainly attributed to an increase in air temperature, although precipitation, glacier size and topographic features also combined to affect the general shrinkage of the glaciers. The 19.3–21.4 km3 estimated glacier mass loss has contributed to an increase in river runoff and water resources.

A two-dimensional coupled tide-surge model was used to investigate the effects of tide-surge interactions on storm surges along the coast of the Bohai Sea, Yellow Sea, and East China Sea. In order to estimate the impacts of tide-surge interactions on storm surge elevations, Typhoon 7203 was assumed to arrive at 12 different times, with all other conditions remaining constant. This allowed simulation of tide and total water levels for 12 separate cases. Numerical simulation results for Yingkou, Huludao, Shijiusuo, and Lianyungang tidal stations were analyzed. Model results showed wide variations in storm surge elevations across the 12 cases. The largest difference between 12 extreme storm surge elevation values was of up to 58 cm and occurred at Yingkou tidal station. The results indicate that the effects of tide-surge interactions on storm surge elevations are very significant. It is therefore essential that these are taken into account when predicting storm surge elevations.

Mass loss of glaciers in the Chinese Altai was detected using geodetic methods based on topographical maps (1959), the Shuttle Radar Topography Mission (SRTM) Digital Elevation Model (DEM) (2000), and the Advanced Space-borne Thermal Emission and Reflection Radiometer (ASTER) stereo images (2008). The results indicate that a continued and accelerating shrinkage has occurred in the Chinese Altai Mountains during the last 50 years, with mass deficits of 0.43 ± 0.02 and 0.54 ± 0.13 m a−1 water equivalent (w.e.) during the periods 1959–1999 and 1999–2008, respectively. Overall, the Chinese Altai Mountains have lost 7.06 ± 0.44 km3 in ice volume (equivalent to −0.43 ± 0.03 m a−1 w.e.) from 1959–2008. The spatial heterogeneity in mass loss was potentially affected by comprehensive changes in temperature and precipitation, and had a substantial correlation with glacier size and topographic settings. Comparison shows that in the Chinese Altai Mountains glaciers have experienced a more rapid mass loss than those in the Tianshan and northwestern Tibetan Plateau (TP), and the mass balance of glaciers was slightly less negative relative to those in the Russian Altai, Himalaya, and southern TP.

The effects of different wind input and wave dissipation formulations on the steady Ekman current solution are described. Two formulations are considered: one from the wave modeling (WAM) program proposed by Hasselmann and Komen and the other provided by Tsagareli and Babanin. The solution adopted for our study was presented by Song for the wave-modifi ed Ekman current model that included the Stokes drift, wind input, and wave dissipation with eddy viscosity increasing linearly with depth. Using the Combi spectrum with tail effects, the solutions are calculated using two formulations for wind input and wave dissipation, and compared. Differences in the results are not negligible. Furthermore, the solution presented by Song and Xu for the eddy viscosity formulated using the K-Profi le Parameterization scheme under wind input and wave dissipation given by Tsagareli and Babanin is compared with that obtained for a depth-dependent eddy viscosity. The solutions are further compared with the available well-known observational data. The result indicates that the Tsagareli and Babanin scheme is more suitable for use in the model when capillary waves are included, and the solution calculated using the K-Profi le Parameterization scheme agrees best with observations.

An electrochemical method on preparation of Al-Si master alloy was investigated in fluoride-based molten salts of 47.7wt.%NaF-43.3wt.%AlF3-4wt.%CaF2 containing 5 wt.% fly ash at 1233 K. The cathodic products obtained by galvanostatic electrolysis were analyzed by means of x-ray diffraction, x-ray fluorescence, scanning electron microscopy, and energy-dispersive spectrometry. The result showed that the compositions of the products are Al, Si, and Al3.21Si0.47. Meanwhile, the cathodic electrochemical process was studied by cyclic voltammetry, and the results showed the reduction peak of aluminum deposition is at −1.3 V versus the platinum quasi-reference electrode in 50.3wt.%NaF-45.7wt.%AlF3-4wt.%CaF2 molten salts, while the reduction peak at −1.3 V was the co-deposition of aluminum and silicon when the fly ash was added. The silicon and iron were formed via both co-deposition and aluminothermic reduction. In the electrolysis experiments, current efficiency first increased to a maximum value of 40.7% at a current density of 0.29 A/cm2, and then it decreased with the increase of current density. With the electrolysis time lasting, the content of aluminum in the alloys decreased from 76.05 wt.% to 48.29 wt.% during 5 h, while the content of silicon increased from 15.94 wt.% to 37.89 wt.%.

Glaciers in the Tuotuo River basin, western China, have been monitored in recent decades by applying topographical maps and high-resolution satellite images. Results indicate that most of glaciers in the Tuotuo River basin have retreated in the period from 1968/1971 to 2001/2002, and their shrinkage area is 3.2% of the total area in the late 1960s. To assess the influence of glacier runoff on river runoff, a modified degree–day model including potential clear-sky direct solar radiation has been applied to the glaciated regions of the river basin over the period 1961–2004. It was found that glacier runoff has increased in the last 44 years, especially in the 1990s when a two-thirds increase in river runoff was derived from the increase in glacier runoff caused by loss of ice mass in the entire Tuotuo River basin.

The superalloys Cu-Ni-Al, Cu-Ni-Fe, and Cu-Ni-Cr were studied as anodes for aluminum electrolysis. The alloys were tested for corrosion in acidic electrolyte molten salt and for oxidation in both air and oxygen. The results showed that the Cu-Ni-Al anodes possess excellent resistance to oxidation and corrosion, and the oxidation rates of Cu-Ni-Fe and Cu-Ni-Al anodes were slower than those of pure copper or nickel. During electrolysis, the cell voltage of the Cu-Ni-Al anode was affected most by the concentration of alumina in cryolite molten salt. The Cu-Ni-Fe anode exhibited corrosion resistance in electrolyte molten salt. Comparatively, the Cu-Ni-Cr anode showed poor resistance to oxidation and corrosion. The testing found that further study is warranted on the use of Cu-Ni-Al and Cu-Ni-Fe as inert alloy anodes.