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It is essential to analyze the dynamic characteristics of regional groundwater levels and their driving factors for the rational development of groundwater in irrigated areas. This article explores the spatial distribution characteristics of the amplitude of groundwater level change in the Shihezi irrigated area by using the ArcGIS interpolation method and contrast coefficient variance method and analyzes the influence factors of dynamic change of groundwater levels by integrating the grey relational degree and path analysis methods and obtaining the sensitivity of each influencing factor to changes in groundwater levels and the relative importance of the influencing factors. The following results are obtained: (1) the groundwater level of the Shihezi irrigated area showed an overall increasing trend from 2012 to 2019, with a fluctuation range of 12.26–14.14 m. The groundwater level in the southeast of the irrigated area showed an upward trend, while the groundwater level in the northwest area showed a downward trend. (2) The groundwater level in the irrigated area first increased, then decreased, and then increased again. The variance of the contrast coefficient in the irrigated area ranged from 0.04 to 11.31, and the fluctuation range of the groundwater level in the central area was higher than that in the northern and southern areas. (3) The irrigated area of cultivated land and evaporation are the main factors affecting groundwater level change in the Shihezi irrigated area. The grey relation analysis shows that the irrigated area of cultivated land has the highest grey correlation degree with the evolution of the groundwater level, which is 0.947, and the average grey correlation index is between 0.74 and 0.95. Path analysis showed that the irrigated area of cultivated land, surface water usage, and evaporation were the main factors affecting groundwater levels. Human activities are one of the main driving forces of groundwater level change, and the research results provide a theoretical basis for the rational utilization and sustainable development of groundwater resources in the Shihezi irrigation area.

Controllable synthesis of tin-doped all-inorganic perovskite (e.g. CsPb1-XSnXBr3) nanocrystals while maintaining tin at the divalent state is of great importance for tuning their optoelectronic properties by changing the chemical composition and geometrical size; however, this remains a non-negligible challenge. In contrast to the conventional high-temperature (>150 °C) synthesis reaction that would more likely facilitate oxidation of divalent Sn2+ to quadrivalent Sn4+, this work demonstrates a facile low-temperature (105-150 °C) hot-injection method to synthesize quantum-confined Sn2+-doped CsPb1-XSnXBr3 nanocrystals with sizes ranging from ∼6.2 nm to ∼8.3 nm depending on the reaction temperature. The optimized reaction temperature of 135 °C led to a Sn2+-doping ratio of 3.4% in CsPb1-XSnXBr3 nanocrystals which exhibited uniform nanoplatelets with an average lateral size of ∼7.4 nm. Furthermore, for the first time, we show that the perovskite nanocrystals are promising for the development of low-cost and trap-assisted photomultiplication UV-photodetectors, and the photodetectors based on CsPb0.966Sn0.034Br3 nanocrystals exhibited wavelength-dependent detectivities in the magnitude of 1011 Jones for UV light extending from 310 nm to 400 nm at a reverse bias of -7 V. The high EQE of ∼1940% at around 340 nm indicates that the devices had a gain at the large reverse bias condition, which is attributed to the formation of interfacial traps by CsPb0.966Sn0.034Br3 nanocrystals that can make the electron injection barrier thin enough to allow electron tunneling in the photodetectors for photomultiplication.

In the context of global warming, the acceleration of the water cycle increases the risk of meteorological drought (MD) and hydrological drought (HD) in the arid region of Northwest China. The Manas River Basin is a typical agricultural oasis and the largest oasis farming area in Xinjiang, Northwest China. Droughts in this basin have significant implications for both agricultural production and the livelihoods of inhabitants. To evaluate the MD and HD and provide information for drought relief in the MRB, the standardized precipitation evapotranspiration index (SPEI) and standardized runoff index (SRI) were calculated using long-term rainfall and runoff data. Subsequently, combined with ArcGIS 10.3 software and the trend analysis method, the SPEI and SRI characteristics were evaluated at different time scales (1-, 3-, 6-, and 12-month). There were three main findings. First, both MD and HD were alleviated, with significantly more HD alleviation. MDs in spring and autumn exhibited a trend of aggravation. The SRIs in summer, autumn, and winter increased significantly at a confidence level of p < 0.01, with an insignificant decline in spring. In the 2010s, the frequency of light drought of MD was stable at 10% to 20%, while severe and extreme droughts increased. The frequency of HDs has decreased since the 1990s. Second, on annual and seasonal scales, MDs occurred mainly as light and moderate droughts. The highest frequency of MD was 24% of moderate droughts in winter. Spatially, the northern region of the MRB was characterized by more frequent light and extreme droughts. Third, runoff in the Manas River Basin increased significantly during the 1990s, which may have been related to the acceleration of glacial retreat in the Tianshan Mountains. This study can effectively reveal the changes in meteorological and hydrological drought in NWC and provide the basis for risk decision-making and management for watershed managers. [ABSTRACT FROM AUTHOR]

In the last few decades, tear-based biosensors for continuous glucose monitoring (CGM) have provided new avenues for the diagnosis of diabetes. The tear CGMs constructed from nanomaterials have been extensively demonstrated by various research activities in this field and are gradually witnessing their most prosperous period. A timely and comprehensive review of the development of tear CGMs in a compartmentalized manner from a nanomaterials perspective would greatly broaden this area of research. However, to our knowledge, there is a lack of specialized reviews and comprehensive cohesive reports in this area. First, this paper describes the principles and development of electrochemical glucose sensors. Then, a comprehensive summary of various advanced nanomaterials recently reported for potential applications and construction strategies in tear CGMs is presented in a compartmentalized manner, focusing on sensing properties. Finally, the challenges, strategies, and perspectives used to design tear CGM materials are emphasized, providing valuable insights and guidance for the construction of tear CGMs from nanomaterials in the future. [ABSTRACT FROM AUTHOR]

The inability to conduct hydrological simulations in areas that lack historical meteorological data is an important factor limiting the development of watershed models, understanding of watershed water resources, and ultimate development of effective sustainability policies. This study focuses on the Manas River Basin (MRB), which is a high-altitude area with no meteorological stations and is located on the northern slope of the Tianshan Mountains, northern China. The hydrological processes were simulated using the China Meteorological Assimilation Driving Datasets for the SWAT model (CMADS) using the Soil and Water Assessment Tool (SWAT) model. Simulated runoff was corrected using calibration/uncertainty and sensitivity program for the SWAT. Through parameter sensitivity analysis, parameter calibration, and verification, the Nash–Sutcliffe efficiency (NSE), adjusted R-square (Radj2{R}_{\text{adj}}^{2}), and percentage bias (PBIAS\text{PBIAS}) were selected for evaluation. The results were compared with statistics obtained from Kenswat Hydrological Station, where the monthly runoff simulation efficiency was NSE=0.64\text{NSE}\hspace{.25em}=0.64, Radj2=0.69{R}_{\text{adj}}^{2}\hspace{.25em}=0.69, and PBIAS=–0.9\text{PBIAS}\hspace{.25em}=\mbox{--}0.9, and the daily runoff simulation efficiency was NSE=0.75\text{NSE}\hspace{.25em}=0.75, Radj2{R}_{\text{adj}}^{2} = 0.75, PBIAS\text{PBIAS} = −1.5. These results indicate that by employing CMADS data, hydrological processes within the MRB can be adequately simulated. This finding is significant, as CMADS provide continuous temporal, detailed, and high-spatial-resolution meteorological data that can be used to build a hydrological model with adequate accuracy in areas that lack historical meteorological data.