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Objectives: Reconstruction of ice flow velocity on the Antarctic Ice Sheet plays a critical role in estimating mass balance and contribution to global sea level rise. However, due to the low availability of optical satellite images before the 1990s, the time span of image pairs ranges from several years to more than ten years, leading to velocity overestimations. In this study, we correct the overestimated ice flow velocity based on the Lagrangian framework. After correction, we analyze the distribution of the overestimation values in the East Antarctic Ice Sheet (EAIS) according to the space and magnitude. Methods: We formulate a set of correction rules, including filtering points of ice flow velocity before correction and whether to retain results after correction. As a transition zone between grounded ice and ice shelf, ice flow velocity near the grounding line is one of the most important parameters of the ice sheet mass balance. In this paper, the overestimations of ice flow velocity are mainly studied from three aspects: First from different regions including inland region, grounding region and ice shelf region, then from different ocean sectors including Weddell Sea, West Indian Ocean, East Indian Ocean and Ross Sea, finally from different glaciers/ice shelves. Results: The average overestimation of ice flow velocity in EAIS is about 28 m/a. Both the grounding and ice shelf regions have larger overestimations than the inland region. The peak correction appears at ±25 km near the grounding line, and the maximum correction exceeds 300 m/a. As for ocean sectors, the overestimation of velocity is the largest in the East Indian Ocean. The average corrections of the Holmes Glacier, Ninnis Glacier, Publications Ice Shelf, and Totten Glacier in this sector exceed 50 m/a, much larger than that of EAIS. Conclusions: This paper shows that only a very small proportion of ice velocity points can meet the correction rules. The points show differences in regional distribution and they are concentrated mainly in the fast-flowing areas such as glaciers and ice shelves. Especially at the grounding zone and ice front areas of ice shelves, the ice flow velocity can be greatly overestimated. By analyzing the corrections and ice flow velocities in different ocean sectors, we found that the spatial acceleration trend of velocity in the East Indian Ocean is obvious and may be related to the interaction between the ocean and the ice shelves. The distribution of corrections varies among different ice shelves and glaciers. For example, Amery Ice Shelf has a larger correction at the confluence of three upstream glaciers, while Shirase Glacier has a larger correction in the inland region. The correction results in this paper have been applied to historical ice flow velocity products for East Antarctica from 1960s to 1980s. The overestimation correction of ice velocity is important for reducing the uncertainty in estimation and forecasting the contribution of Antarctic mass loss to the global sea level rise. [ABSTRACT FROM AUTHOR]

Since the new century aluminum-air battery has become one of the most ideal energy batteries due to its high specific energy green environmental protection, economical, last charging speed (mechanical charging) and abundant anode resources，The open circuit voftage and anode activity of the alkaline aluminum-air battery are much higher than those of the neutral salt system，but the hydrogen evofution corrosion of the alkaline aluminum-air battery and the pofarization of the aluminum anode during battery use are very serious，which greatly limited the development of aluminum-air batteries. In this paper the research and development status of alkaline aluminum-air battery aluminum alloy anodes on anode slow release and pofarization reduction are reviewed in the aspect of the effects of alloying elements in aluminum alloy anode materials and related mechanisms，the influence of metal oxides， the influence of impurity elements，the heat treatment of later alloys，the effect of grain refinement and so on，which propose the next research direction of aluminum-air battery aluminum alloy anodes. [ABSTRACT FROM AUTHOR]

The flotation tailings of selenium removal residue produced in the copper smelting system contain valuable elements such as Pb, Sb, Te, and Bi. For the tailings, the reduction-leaching was carried out to separate lead and enrich valuable metals such as Sb, Te，and Bi. The effect of carbon reduction pretreatment on leaching efficiency of lead was investigated. The effects of liquid-solid ratio, NaOH concentration, reaction temperature, and reaction time on leaching efficiency of lead were also explored. The results show that the leaching rate of lead from tailings is obviously improved after carbon reduction pretreatment. The optimum conditions of carbon reduction pretreatment are roasting temperature 550 °C , roasting time 6 h, and the ratio of carbon powder to material 1 : 20. The optimum conditions of leaching are liquid-solid ratio 8 : 1, NaOH concentration 180 g/L, leaching temperature 90 °C，and leaching time 1 h. Under these conditions? the leaching rate of lead is the highest (97. 1%). The effective leaching of lead makes the elements such as Sb, Te, and Bi in the tailings enriched, which lays a foundation for the subsequent extraction of valuable elements. [ABSTRACT FROM AUTHOR]

A new type of A1 0» 017Ga 0. 885Mn 0. 038Ca 0. 048Cu(wt % ) anode alloy was fabricated through a series of processes including casting，calendering，and annealing. EIS and polarization curve analysis were conducted to study its corrosion behavior and electrochemical performance in different concentrations of NaOH solution. The results show that with the increase of NaOH concentration, the self corrosion rate of the alloy anode is gradually increasing，and the corrosion rate of A1 0. 017Ga 0. 885Mn 0. 038Ca 0. 048Cu alloy in 4 mol/L NaOH solution is significantly reduced. The discharge voltage can still be maintained at about 1 V at a current density of 120 mA/cm2， and the anode energy density is also the highest，reaching 6. 056 kW • h/kg，which is more suitable for continuous constant current discharge at different current densities. Moreover，the constant current discharge and EIS results of the alloy are in good agreement with the corrosion characteristics. [ABSTRACT FROM AUTHOR]