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In this work, a highly efficient and rapid method for simultaneously removing cationic dyes from aqueous solutions was developed by using monodispersed mesoporous silica nanoparticles (MSNs) as the adsorbents. The MSNs were prepared by a facile one-pot method and characterized by scanning electron microscopy, transmission electron microscopy, Fourier-transform infrared spectroscopy, and Brunauer-Emmett-Teller. Experimental results demonstrated that the as-prepared MSNs possessed a large specific surface area (about 585 m2/g), uniform particle size (about 30 nm), large pore volume (1.175 cm3/g), and narrow pore size distribution (1.68 nm). The materials showed highly efficient and rapid adsorption properties for cationic dyes including rhodamine B, methylene blue, methyl violet, malachite green, and basic fuchsin. Under the optimized conditions, the maximum adsorption capacities for the above mentioned cationic dyes were in the range of 14.70 mg/g to 34.23 mg/g, which could be achieved within 2 to 6 min. The probable adsorption mechanism of MSNs for adsorption of cationic dyes is proposed. It could be considered that the adsorption is mainly controlled by electrostatic interactions and hydrogen bonding between the cationic dyes and MSNs. As a low-cost, biocompatible, and environmentally friendly material, MSNs have a potential application in wastewater treatment for removing some environmental cationic contaminants.

In this study, we document the kinematics and Late Quaternary slip rates of actively developing faults and folds on the northern side of the Altyn Tagh Fault (ATF) that accommodate uplift and lateral expansion of the northern Tibetan Plateau. Field observations and detailed measurements using Unmanned-Aerial-Vehicle Structure-from-Motion high-resolution imagery of offset fan surfaces, gullies, and channel risers coupled with optically stimulated luminescence and 10 Be ages constrain the timing and slip rates of the Sanweishan Fault (SWSF) and Nanjieshan Fault (NJSF) systems. The NE striking SWSF is characterized by sinistral strike slip with a top-to-the-NW thrusting component. Offset geomorphic markers and dating results yield Pleistocene strike slip and vertical uplift rates of 0.06-1.25 mm/a and 0.05-0.08 mm/a, respectively. The E-W trending NJSF is dominated by north and south directed thrusting and km-scale folding with variable components of sinistral strike slip. The calculated total N-S shortening rate across the NJSF is~0.3 mm/a. Low rates of deformation for the SWSF and NJSF account for less than 10% of the total intraplate strain accommodated along the northeasternmost ATF system. Over a 1,000-km length, the northward expansion of the Tibetan Plateau occurs by progressive northeastward growth of a transpressional duplex rooted SE into the ATF. An assumed crustal strength discontinuity along the northeast trending southern margin of the Tarim Craton focuses oblique convergence along the ATF. Oblique-slip thrusting and sinistral strike slip along the ATF and to the north accommodate the oblique convergence, consistent with the ENE directed geodetically derived crustal velocity field driven by India's continued indentation 1,500 km to the south.

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The Altyn Tagh fault (ATF) is a major intracontinental strike‐slip fault system that defines the northern margin of the Tibetan Plateau. The fault system loses its obvious surface expression north of the Qilian Shan fold‐and‐thrust belt, but may link eastward with multiple faults in the northern Hexi Corridor and southern Alxa block. To better understand the potential connectivity and displacement transfer between the ATF and the northern Hexi Corridor fault array, we carried out a multidisciplinary field and remote sensing‐based investigation of the actively deforming Heishan and Jinta'Nanshan region north of Jiayuguan City. We document Quaternary sinistral strike‐slip motion on the Heishan fault (HF) system and active sinistral transpression within a 70‐km‐long, E‐W deforming belt east of the Heishan, which is characterized by multiple left‐stepping, en‐échelon Quaternary folds and linking faults. Cosmogenic 10Be dating of displaced terrace surfaces yields a vertical slip rate of ∼0.2 mm/a for the northern Heishan thrust and a sinistral strike‐slip rate of 0.6 ± 0.2 mm/a for the HF. Within the uplifted core of the Heishan massif, the HF contains ductilely deformed Paleozoic basement lithologies with dextral‐sense shear fabrics that indicate that the modern HF has reactivated and inverted an older shear zone. A previously published magnetotelluric profile across the HF system suggests that it roots into a steep, deeply penetrating fault that is unlinked to the Qilian Shan thrust wedge. Instead, we suggest that the active sinistral deformation belt of the Heishan‐Jinta'Nanshan represents the eastward‐evolving, upper crustal expression of the modern ATF system.

The ∼1,000 km‐long Bolokenu‐Aqikekuduk fault (Dzhungarian fault, BAF) is one of the major right‐lateral strike‐slip faults that cut across the Tian Shan Range. Although the BAF plays an important role in accommodating crustal shorting of the Tian Shan and cuts through densely populated cities, little is known about its late Quaternary tectonic activity or earthquake history. Here we quantify the late Quaternary dextral strike‐slip rate of the BAF along the Jinghe segment based on interpretation of high‐resolution remote sensing images and structure‐from‐motion (SfM)‐derived DEMs, field observations and the abandonment ages of displaced alluvial fans, which were constrained by optically stimulated luminescence (OSL) and cosmogenic 10Be depth profile dating methods. Using the offset of fan risers and gullies incised into the fan surfaces, we yielded a right‐lateral strike‐slip rate of 3.2 + 1.4/−1.1 mm/a. Compared with the entire crustal shortening rates across the Tian Shan, the BAF accommodates ∼23% of the N‐S crustal shortening rate. Additionally, a paleoseismic trench reveals four events since the late Pleistocene with an average recurrence time of ∼4–6 ka. The last event occurred after ∼6.6 ka, which is slightly larger than the average recurrence time, suggesting that the BAF represents a potential high seismic risk for the densely populated area nearby.

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