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The remnants of explosive devices contain copper, aluminium, tin and other non-ferrous metals, which often play a key role in the detection of explosive cases. Therefore, compared with the remnants of explosive devices made of plastic and other materials, the discovery and extraction of non-ferrous metals remains is particularly important in the field investigation of explosive cases, especially the small non-ferrous metal remains that are difficult to be found by the naked eyes. It is necessary to study new techniques and methods for the discovery and extraction of residues. In this study, the automatic screening technology of small non-ferrous metal residues in explosive devices is analysed. Through the comparative analysis of various separation and extraction technologies, it is believed that electromagnetic separation technology is expected to be used in the rapid screening of small non-ferrous metal residues in explosive devices.

In order to firstly explore the stable isotope evolution of Shiyi glacier system in the central Qilian Mountains, a total of 167 samples have been collected from newly deposited snow, surface snow, snowpits, meltwater and glacier-fed river water from July 2012 to November 2013. The results indicated that only the newly deposited snow in 23 November 2013 showed a significant ‘altitude effect’, whereas surface snow had a reverse ‘altitude effect’ owing to evaporation and sublimation in summer 2012 and 2013. The d

In order to explore the glaciochemistry of Shiyi glacier in the central Qilian Mountains, a total of 142 samples have been collected for fresh snow, surface snow, snowpit and meltwater from July 2012 to November 2013. The results indicated cations dominated the glaciochemistry, especially the high Ca2+ concentration. Relatively high Cl- and Na+ concentrations were mainly contributed by desert dust aerosols and the atmospheric aerosols from warm water bodies such as the Black, Caspian, and Aral seas. The analysis also confirmed the chemical ions in fresh snow are mainly contributed by atmospheric wet deposition. Surface snow is mainly influenced by dry deposition, and snowpits are influenced by both atmospheric deposition and leaching process, while meltwater is influenced by water-rock interactions. The profile of ionic concentration in the snowpit became more smoothed during ablation period owing to the influence of leaching. The elution sequence of the snowpit in the Shiyi Glacier was: SO42- > K+ > Ca2+ > Mg2+ > Na+ > Cl- > NO3-. The chemical concentrations for meltwater are mainly influenced by water dilution and soil thawing. The ions in snow in the central Qilian Mountains showed relatively lower concentrations than in the western Qilian Mountains, Tianshan Mountains and Altai Mountains. It was closer to balance than in glaciers in the central Tibetan Plateau, but was higher than in the southern Tibetan Plateau. Different ionic sources and dissolution process had caused the differences of chemical composition for fresh snow, surface snow, snowpit and meltwater, and these chemical compositions reflected the atmospheric background values in the northern Tibetan Plateau. (C) 2014 Elsevier Ltd and INQUA. All rights reserved.

The isotopic composition of precipitation has been measured in samples simultaneously collected during individual precipitation events at a high-altitude station (Hulugou at 3260 m a.s.l.) in the middle Qilian Mountains, northwestern China. The observed changes of delta O-18 (delta D) and deuterium excess with surface air temperature, precipitation and season have been evaluated to derive information on water vapor sources and the effects from monsoon moisture. The results indicated monsoonal moisture can arrive in the Qilian Mountains in summer, as indicated by: (1) under temperatures between 8 degrees C and 15 degrees C, the precipitation events are characterized by the decrease of delta O-18 and d excess owing to the influence from monsoonal moisture; (2) delta O-18 and dD showed statistically negative correlation with precipitation, which reflected the amount effect in at precipitation events scale; (3) not only the water vapor transporting vector but also composite circulation maps verified the arrival of monsoonal moisture in summer along the eastern margin of the Tibetan Plateau, which made a great contribution to regional precipitation under climate warming. (C) 2014 Elsevier Ltd and INQUA. All rights reserved.

Global warming would inevitably lead to the increased glacier-snow meltwater and mountainous discharge. Taking an example the Hulugou River Basin in the Qilian Mountains, this study confirmed the contribution of cryosphere to runoff by means of the isotope hydrograph separation. The hydro-geochemistry and the isotope geochemistry suggested that both the meltwater and rainwater infiltrated into the subsurface and fed into the river runoff of the Hulugou River Basin in the form of springs. The isotopic composition of river water and underground water was close to the Local Meteoric Water Line, and the delta O-18 and delta D ranged among precipitation, glacier-snow meltwater and frozen soil meltwater. The results indicated that 68% of the recharge of the Hulugou River water was the precipitation, thereinto, glacier-snow meltwater and frozen soil meltwater contributing 11% and 21%, respectively. For tributary-1, precipitation accounted for 77% of the total stream runoff, with frozen soil meltwater accounting for 17%, and glacier-snow meltwater only supplied 6%. During the sampling period, the contribution of surface runoff from precipitation was 44% to tributary-2, and glacier-snow meltwater had contributed 42%; only 14% from frozen soil meltwater. For tributary-3, precipitation accounted for 63% of the total runoff, and other 37% originated from the frozen soil meltwater. According to the latest observational data, the glacier-snow meltwater has accounted for 11.36% of the total runoff in the stream outlet, in which the calculation has been verified by hydrograph separation. It is obvious that the contribution of ayosphere has accounted for 1/3 of the outlet runoff in the Hulugou River Basin, which has been an important part of river sources. This study demonstrated that the alpine regions of western China, especially those basins with glaciers, snow and frozen soil, have played a crucial role in regional water resource provision under global warming. (C) 2014 Elsevier B.V. All rights reserved.