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Evapotranspiration is a crucial component of the hydrological cycle and Gross Primary Productivity (GPP) is the largest flux in the global carbon cycle. However, both evapotranspiration and GPP are significantly affected by climate disasters, especially extreme drought events. Therefore, in this study, MODIS product data from 2002 to 2021 was used to analyze the spatiotemporal variations of actual evapotranspiration (ET), potential evapotranspiration (PET) and GPP within the Haihe River Basin. Then extreme drought events were identified by using EDDI drought index. A statistical analysis was performed to assess the impact of extreme drought on ecosystem evapotranspiration and GPP. The results showed that: (1) the annual evapotranspiration in the Haihe River Basin fluctuated greatly, ET showed a general increasing trend which was higher in the eastern region and lower in the central and western regions, PET showed an overall decreasing trend which was higher in the central and western regions and lower in the eastern region; (2) the annual GPP in the Haihe River Basin from 2002 to 2021 was 646.88 g C/m2/a and the increase rate was 14.75 g C/m2/a, which exhibited a decreasing trend from the northern to the southern and central-western regions; (3) under extreme drought conditions, ET decreased compared with the mean value, while PET increased, the Zhangweihe and the Tuhaimajiahe sub-basins were the most affected, with ET decreasing by 16.36% and PET increasing by 7.00% compared to the reference year. Additionally, extreme drought led to a decrease in GPP, with a reduction ranging from 7% to 18%. • The ET and GPP have a similar temporal and spatial distribution pattern. • The negative effect of extreme drought on actual evapotranspiration reached 8.05%. • The negative effect of extreme drought on gross primary productivity reached 12.0%. [ABSTRACT FROM AUTHOR]

The data source and resolution of DEM will affect the extraction of watershed features and flood simulation precision. In this paper, based on the 7 cm resolution DEM of the Liulin watershed obtained by tilt photography technology, the nearest neighbor interpolation, bilinear interpolation, and cubic convolution methods were used to resample DEMs with 1m and 30m resolution, and 6 resampled DEMs were obtained. The Aster 30m resolution DEM was downloaded from the geospatial data cloud. The watershed features were extracted from the 7 DEMs and compared. Based on these DEMs, the HEC-HMS model was established. 20 flood events were selected in the Liulin watershed for model calibration and verification. The results showed that the resampling method has little effect on the topographic features, but there were some differences between the resampling and downloaded DEM topographic features. The flood simulation results of the 1m resolution DEM-based HEC-HMS model are slightly better than that of the 30m resolution DEM-based model. The resampled 30m resolution DEM-based model performed identically with Aster 30m resolution DEM-based model. Therefore, an Aster 30m DEM can be used for flood simulation in a watershed that lacks measured high-precision topographic data. • Create DEMs using various resampling techniques from tilt-photographed terrain at 7 cm resolution. • The simulated results of resampling DEMs and Aster 30m DEM were compared. • The resampled 30m resolution DEM performed identically with Aster30m resolution DEM. [ABSTRACT FROM AUTHOR]

A large quantity of pollutants is washed off by stormwater during rainfall events. Polluted storm runoff deteriorates the water quality of receiving water bodies, which is becoming a main threat to urban water environment. In this work, five rainfall events were monitored to clarify the characteristics of land surface pollution in Wuqing district, China. Four pollutant indicators of storm runoff samples, including chemical oxygen demand (COD), total phosphorus (TP), total nitrogen (TN) and ammonia nitrogen (NH 3 -N), were analyzed and then used to validate the parameters of a model established by Infoworks integrated catchment modeling (ICM). The land surface pollutant loads of metropolitan area for four different rainfall scenarios and the variations in pollutants concentration in urban rivers were illustrated based on the model. The simulated results showed that the volume of runoff increased from 31.8 × 104 m3 to 139.7 × 104 m3 with the increase in the return period. The EMCs (Event Mean Concentration) of pollutants, however, were negatively correlated with return periods and the maximum drop was approximately 67%. Furthermore, the increased runoff enhanced the dilution effect and reduced the residence time of pollutants in rivers, which were the main reasons for the decrease of the pollutants concentrations. The results suggested that the runoff should be taken into account when considering the effects of surface pollution on urban river water quality. [Display omitted] • Field experiments were conducted to confirm the surface pollution characteristics. • The simulated pollutant concentration decreases when storm return period increases. • The peak of pollutant concentration in rivers is higher for 1-year return period. • Rainfall runoff significantly affects the concentration of pollutant in rivers. [ABSTRACT FROM AUTHOR]

(1- x)SrWO 4 - x TiO 2 (x = 0, 0.05, 0.10, 0.15, 0.20, 0.25) were prepared by a conventional solid-state sintering method. The X-ray diffraction and Rietveld refinement data show that the SrWO 4 phase can coexist with the TiO 2 phase to form composite ceramics. Scanning electron microscopies show that the samples have dense and uniform particles. The lattice vibration properties were analyzed in detail by Raman and Infrared spectra. The intrinsic properties calculated by the FPSQ model based on FTIR spectra agree well with the results derived from the Clausius-Mossotti and damping equations. There is a positive relativity between the Raman shifts of the v 1 (A g) modes and the permittivities, while a negative relativity exists between the full width at half-maximum values of the B g modes and the dielectric losses. The measured dielectric constant values of SWT ceramics are between 7.05 and 9.30, the range of quality factor is 7669–63232 GHz, and the τ f values of which are between −24.44 and −84.37 ppm/°C. Among them, when x = 0.15, the SWT ceramics achieved the most excellent dielectric properties with ε r = 8.06, Q × f = 42,617 GHz (f = 15.70 GHz), τ f = −35.07 ppm/°C. • The lattice vibrational modes were analyzed by Raman and far-infrared spectra. • The intrinsic properties of the samples were calculated by the Clausius-Mossotti (C-M) as well as damping equations. • The contribution of various vibrational modes on the dielectric properties has been comprehensively studied. • Lattice vibration characteristics and structure-characteristic relationship are deeply understood. • Our research has achieved a semi-quantitative description. [ABSTRACT FROM AUTHOR]

Determining the features of soil CO 2 and N 2 O emissions and the driving factors of deficit irrigation is of great significance for optimizing cropland management modes. In this study, the experimental plots were selected in a typical area of the North China Plain during the whole growth period of winter wheat. Six irrigation levels were designed to investigate the effect of deficit irrigation on CO 2 and N 2 O emissions and wheat yield. CK represents reference irrigation (full-water irrigation), and T1-T5 represent irrigation water decreasing by 10%, 20%, 30%, 40% and 50%, respectively. The experiment showed that soil CO 2 and N 2 O emissions decreased under the deficit irrigation treatments (T1, T2, T3, T4 and T5). Pearson correlation analysis showed that there were significant correlations between the CO 2 emissions and soil temperature or water-filled pore space (WFPS) under the different irrigation treatments, and these correlations had a significant linear relationship. However, there was no discernible correlation between the N 2 O emissions and soil temperature or WFPS under the other irrigation treatments except the CK treatment. Compared with that of the CK treatment, the equivalent CO 2 of the T1-T5 treatments decreased by 8.6%, 5.7%, 14.3%, 14.1% and 19.3%, respectively. Compared with the CK treatment, the T3-T5 treatments significantly decreased the N 2 O emissions (P < 0.05), and the reduction in CO 2 by deficit irrigation did not reach a significant level (P > 0.05). Moreover, some deficit irrigation treatments had negative influences on the yield of winter wheat. Through the TOPSIS method and RSR method, the effects of the irrigation levels on equivalent CO 2 and wheat yield were evaluated comprehensively. The T3 treatment was shown to be the best irrigation level for the conservation of wheat yield and reduction of greenhouse gas emissions. Therefore, the corresponding irrigation water amount under the T3 treatment could be regarded as the most appropriate scheme. Image 1 • Deficit irrigation (T1-T5) resulted in a decrease in CO 2 and N 2 O emissions. • Soil temperature and moisture had a significant effect on CO 2 emissions. • Soil temperature and moisture had no impact on N 2 O emissions. • The most appropriate irrigation level was determined using two evaluation methods. • Wheat yield and greenhouse gas emissions were considered in the evaluating process. [ABSTRACT FROM AUTHOR]

• A long series of highly accurate soil moisture data was combined. • SWDI was improved and extended to the monthly scaled drought index. • Temporal features of SWDI were characterized in four geographical regions. • The relationship among drought indexes (SPI, SWDI and VCI) was explored. Drought monitoring and assessment are of great importance due to the costly damage caused by drought. Datasets, drought indexes and drought relationships are three critical areas of drought research. Satellite-retrieved soil moisture (SM) products derived from the European Space Agency Climate Change Initiative (ESA CCI) show application potential in drought monitoring. However, the products are missing certain data in some areas. The model-assimilated SM product derived from the Global Land Data Assimilation System (GLDAS) was used to supplement these missing data. The main goals of this paper are to characterize agricultural drought after the utility and applicability of the combined SM product and the monthly scaled soil water deficit index (SWDI) have been evaluated and to investigate the relationships among meteorological, agricultural and vegetation droughts. First, we provided a long series of highly accurate SM products through simple calculations. The drought index, SWDI, was extended to a monthly scale for long-term drought analysis by using the combined SM product. The probability of detection (POD) between the SWDI and in situ drought records performed fairly well. Half of the 566 stations had PODs higher than 0.9, and one-third of these stations had POD values equal to 1. Through correlation analysis and grey incidence analysis (GIA) between the standardized precipitation index (SPI) and SWDI, we found that the propagation time from meteorological drought to agricultural drought was shorter under drier conditions than wetter conditions, and at the regional scale, the response time ranged from 1 month to 2.5 months. Correlation analysis between the SWDI and vegetation condition index (VCI) indicated that there was no delay effect from agricultural to vegetation drought on a monthly scale in most parts of China except in several provinces distributed in the South; additionally, there was a significant time lag in forests, while grassland and agriculture were more inclined to have no time lag or the response time was less than 1 month. [ABSTRACT FROM AUTHOR]

The atomic layer deposition (ALD) technique has been extensively utilized for depositing metal oxide (MO) thin films, particularly as gate insulators in thin film transistors (TFTs). However, research on MO semiconductors as channel layer materials in TFTs using ALD is limited, especially for fully ALD-fabricated MO TFTs. In this study, fully ALD-fabricated InAlO TFTs were developed, with optimized aluminum doping content and annealing temperature to enhance the electrical properties and stability. The InAlO TFTs, fabricated with a cycle ratio of 15:1 and annealed at 350 °C, exhibit superior performance, including a field-effect mobility of 7.2 cm2/V·s, a subthreshold swing of 165 mV/decade, and an on/off current ratio of 2.3 × 106, with a threshold voltage of only 0.1 V. Additionally, they demonstrated good stability, with a threshold voltage shift of 0.11 V under positive bias stress. The improved electrical properties and stability are attributed to reduced carrier concentration and the inhibition of oxygen defect generation, achieved through appropriate annealing temperatures and aluminum doping. Thus, the development of fully ALD-fabricated high-performance TFTs holds promise for next-generation display technologies as pixel-driving circuits. • Fully ALD-fabricated InAlO TFTs were developed. • InAlO TFTs with a cycle ratio of 15:1 and annealed at 350 °C exhibit high mobility and low subthreshold swing. • The threshold voltage shift is only 0.11 V under positive bias stress. [ABSTRACT FROM AUTHOR]

The problem of insufficient water for ecological purposes in the Luanhe River basin requires urgent resolution. The regional hydrological cycle is affected by the Panjiakou-Daheiting Reservoir system and by changes in land use in the upper watershed. Therefore, this system was selected as a study area to simulate ecological reservoir operation and analyze the effects of changes in land use on ecological operation. A physical habitat simulation model (PHABSIM) was built to determine the minimum and suitable ecological water demand. Then, an ecological reservoir operation model using an improved differential evolution (DE) algorithm was established. Simulated inflow data under the land use conditions in 1970 and 2015 were input into the model, and the effects of changes in land use on ecological operation and on the weighted usable area (WUA) for cyprinoids were calculated. The results show that ecological reservoir operation significantly improves the ecological water supply and increases cyprinoid habitat. The changes in land use led to a decrease in annual runoff, which further reduced the urban water supply by 0.67%–2.25% and the ecological water supply by 0.45%–2.04% at different flow frequencies. The land use changes also caused the WUA to decrease by 1746–2999 m2/km at different flow frequencies, with a decrease rate of 1.04%–6.28%. This study could provide valuable information for water resource managers operating reservoirs in river ecosystems and planning to cope with water shortages caused by land use change in water-deficient areas. • Determining the ecological water demand by synthesize hydrological and habitat methods. • The changes in land use result in a decrease in water supply and fish habitat. • Urban water supply is most affected by changes in land use at different flow frequencies. • Effects on the ecological water supply become stronger as the flow frequency increases. [ABSTRACT FROM AUTHOR]

Microchannel heat sinks have great potential in cooling miniaturized electronics with high heat flux. However, manufacturing difficulties and pressure drop penalty are concerns need to be considered. In this work, pizza-box shaped microchambers were embedded in LTCC substrates to cool high power SiP modules. Each microchamber heat sink has a manifold inlet located just below the hot spot to generate vertical impingement jet for direct cooling of the hot spot. By adopting the form of microchamber instead of microchannels, the pressure drop was reduced. A flow rate of 10ml/min driven by a pressure below 1 kPa was sufficient to reduce the maximum temperature from 180 °C to 50°C. Run-through Ag pillar arrays were also used to enhance both conductive and convective heat transfer. The substrate thermal resistance was decreased by two orders of magnitude to about 0.2 K/W. The Nusselt number was increased by 60% ∼ 110%. An index with obvious physical significance, ease measurement, and small uncertainty has been defined to evaluate the cooling efficiency. The cooling efficiency of the microchamber heat sinks could reach 95% under normal temperature environment. Fast and effective cooling has been achieved and high system reliability was also guaranteed. • Microchambers with pizza-box shape were embedded in substrates for cooling high power SiP at low pumping and cost. • Run-through Ag pillars and hot-spot oriented manifold inlets were used to enhance conductive and convective heat transfer. • Fast effective cooling and high system reliability were simultaneously guaranteed. • A cooling efficiency index suitable for on-site assessment and monitoring of the integrated heat sinks were defined. • The effects of the pillars, flow rate, power, and ambient/inlet water temperature were studied systematically. [ABSTRACT FROM AUTHOR]

A hydrological model (Soil and Water Assessment Tool, SWAT) of the Luanhe River Basin was built based on collected hydrological and meteorological data to better understand how the soil water content varies under climate change. To assess the applicability of the eight selected global climate models (GCMs), four single indicators and one comprehensive indicator were calculated at multiple stations. According to the evaluation results, a weighted multimode ensemble was established. To downscale and correct the deviation from the meteorological data while maintaining the trend signal, the enhanced Delta-DCSI technique was utilized. Eventually, the corrected GCM data were used to drive the SWAT model to simulate the spatial and temporal changes in the soil water content in the Luanhe River Basin under future scenarios. The results indicated that (1) the SWAT model was suitable for and capable of simulating hydrological processes in the basin; (2) the SWAT model can be accurately driven by multimodel ensemble data after model optimization; (3) the soil water content in the basin slowly increased and fluctuated over time; and (4) in the future, lower soil water contents will occur in a few northern subbasins, and consistently higher water contents will occur in the remaining areas. The findings could provide a scientific basis for water resource management and ecological environmental protection in the Luanhe River Basin. [ABSTRACT FROM AUTHOR]

To analyse the influence of nonpoint source pollution on the water quality in the Daheiting Reservoir, based on measured hydrological and water quality data, a coupled hydrological model for the Panjiakou-Daheiting interval basin and a two-dimensional vertical hydrodynamic and water quality model for the Daheiting Reservoir were constructed. The water quantity and water quality output results of the upstream hydrological model (Soil and Water Assessment Tool, SWAT) were input into the reservoir hydrodynamic-water quality model (CE-QUAL-W2) as boundary conditions. The annual distribution of pollutants in the reservoir was simulated and analysed. The results showed that nutrients such as nitrate nitrogen and phosphate in the reservoir area were stratified, and there were seasonal differences due to the water temperature, dissolved oxygen and upstream inflow. After lowering upstream pollution emissions, the water quality in the reservoir was improved significantly, and compared to that of reducing point source pollution, the effect of reducing nonpoint source pollution is more obvious. • Variations of water temperature and water quality in the reservoir are investigated under the coupled model. • Stratification of water temperature and water quality is obvious in front of the dam. • The concentration of pollution in the reservoir declined more after non-point source pollution was reduced. [ABSTRACT FROM AUTHOR]

Unlabelled Image • A new drought index, Non-stationary Standardized Streamflow Index, was proposed. • The index was defined using a probability model with external forces as covariates. • The model included climate-driven and human-induced non-stationarity in streamflow. • The index evaluated hydrological droughts effectively under a changing environment. The aim of this paper is to propose a new non-stationarity hydrological drought index, which incorporates the climate-driven and human-induced non-stationarities in streamflow. For this purpose, significant teleconnection indices have been selected by correlation analysis to represent large-scale climate variability, and human-induced indices have been calculated using the Soil and Water Assessment Tool (SWAT) to indicate varying anthropogenic forcing. Whereafter, a non-stationary probability model fitted to streamflow series has been developed using the climate-driven and human-induced indices as covariates. Base on the non-stationary model, we present a variation of the classical Standardized Streamflow Index (SSI), named Non-stationary Standardized Streamflow Index (NSSI). Focusing on the streamflow records of Luanhe River basin from 1958 to 2011, a comparison of performance between NSSI and SSI has been conducted to demonstrate the capability of the NSSI. Finally temporal-spatial patterns of drought during the last 40 years over the basin have been estimated by using the NSSI. The results show that the non-stationary model describes the variability of streamflow better than a stationary one, and the covariates selected with Akaike information criterion (AIC) provide insights into non-stationary behaviors. Since the NSSI effectively accounts for the non-stationarities of streamflow associated with climate changes and human activities, it provides more reasonable and satisfactory results than the SSI. Additionally, it is indicated that serious long-term droughts generally appeared more frequently in the southeast of Luanhe River basin, and an obvious aggravating tendency of drought was observed in this area during 1971–2011. The presented NSSI enables hydrological droughts to be better characterized in a non-stationary context, thus providing valuable references for the improvement of drought index and the drought related policy-making. [ABSTRACT FROM AUTHOR]