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Aqueous zinc-ion batteries (ZIBs) offer numerous advantages, such as high energy density, enhanced safety, and low cost, making them an ideal choice for energy storage and conversion applications in the “postlithium” era. Hydrogel electrolytes, as the key component of flexible ZIBs, combine the ionic conductivity of traditional water electrolytes with the dimensional stability of solid polymer electrolytes. However, it remains a challenge to design comprehensive and appropriate hydrogel electrolytes to provide flexible ZIBs with good reversibility and versatility. This review discusses the engineering design of hydrogel electrolytes required for flexible ZIBs from the viewpoint of an electrolyte designer. The basic properties of the hydrogel electrolytes, zinc anodes, cathodes and electrolyte stabilization effects are described in detail. Furthermore, we explore the various challenges faced by hydrogel electrolytes and propose corresponding strategies. Finally, the review offers insights into the future development of hydrogel-stabilized ZIBs. [ABSTRACT FROM AUTHOR]

With the growing demand for scalable and cost-effective electrochemical energy storage systems, aqueous Zn-ion batteries (ZIBs) have attracted attention as cheap, efficient, and safe energy storage devices. However, practical applications of ZIBs are hampered by some challenges, such as Zn dendrite growth, corrosion, passivation, byproducts, cathodic dissolution, and harmful electrostatic interactions. These problems are directly associated with the electrolytes of ZIBs, which are in contact with both the cathode and anode. Recently, several studies have been conducted to optimize ZIB electrolytes. The electrolyte system includes the electrolyte and solvent. The solvent ensures stable operation of the electrolyte and improves the electrochemical efficiency of the cathode and anode, thus improving the electrochemical performance and stability of ZIBs. However, to date, the effect of solvents on the stability of Zn anodes remains unclear. Therefore, there is a need for detailed studies on solvents for ZIB electrolytes. Herein, we review the research progress in the stabilization of Zn anodes using various solvents, including alcohols, amines, acetonitrile, lipids, ethers, and dimethyl sulfoxide. In addition, we discuss the effects of different solvents on the stabilization mechanism of Zn anodes. Finally, the challenges and prospects of solvents used for stabilizing Zn anodes in electrolytes are analyzed, and future research directions for ZIB electrolyte dissolution are proposed. [ABSTRACT FROM AUTHOR]

The water resources of the Chari River basin, contributing more than 90% of the water to one of the largest lakes in Africa, known as Lake Chad, are highly vulnerable to natural and anthropogenic changes. Therefore, the changes in water resources were predicted for the next 20 years (i.e., 2016-35) by using the harmonic regression model (HRM), one of the most sophisticated time series methods, and also projected under representative concentration pathways (RCPs) by using the multimodel approach for the periods 2021-50, 2051-80, and 2081-2100, with respect to the baseline period (1971-2001). The Tropical Rainfall Measuring Mission (TRMM), Climatic Research Unit (CRU), and dynamically downscaled climatic data were used in the analysis of the present study. The results showed that under MME-RCP2.6 (multimodel ensemble of RCMs), low flow (average of low-flow months, December-July), high flow (August-November), and annual flow were projected to decrease in the future. In contrast, under MME-RCP4.5 and MME-RCP8.5, high and annual flows were projected to increase in all three time horizons, while low flow will decrease except in 2021-50 under MME-RCP8.5. In the next two decades, the HRM showed decrease in all type of flows (low, high, and annual), very similar to the results under MME-RCP2.6 for the same period. In contrast, almost all flows are expected to increase underMME-RCP4.5 andMME-RCP8.5 in the next two decades. On the whole, the flows are expected to decrease under the HRM and RCP2.6 but to increase under RCP4.5 and RCP8.5. [ABSTRACT FROM AUTHOR]

The knowledge of water storage variations in ungauged lakes is of fundamental importance to understanding the water balance on the Tibetan Plateau. In this paper, a simple framework was presented to monitor the fluctuation of inland water bodies by the combination of satellite altimetry measurements and optical satellite imagery without any in situ measurements. The fluctuation of water level, surface area, and water storage variations in Lake Qinghai were estimated to demonstrate this framework. Water levels retrieved from ICESat (Ice, Cloud, and Elevation Satellite) elevation data and lake surface area derived from MODIS (Moderate Resolution Imaging Spectroradiometer) product were fitted by linear regression during the period from 2003 to 2009 when the overpass time for both of them was coincident. Based on this relationship, the time series of water levels from 1999 to 2002 were extended by using the water surface area extracted from Landsat TM/ETM+ images as inputs, and finally the variations of water volume in Lake Qinghai were estimated from 1999 to 2009. The overall errors of water levels retrieved by the simple method in our work were comparable with other globally available test results with r = 0.93, MAE = 0.07 m, and RMSE = 0.09 m. The annual average rate of increase was 0.11 m/yr, which was very close to the results obtained from in situ measurements. High accuracy was obtained in the estimation of surface areas. The MAE and RMSE were only 6 km2, and 8 km2, respectively, which were even lower than the MAE and RMAE of surface area extracted from Landsat TM images. The estimated water volume variations effectively captured the trend of annual variation of Lake Qinghai. Good agreement was achieved between the estimated and measured water volume variations with MAE = 0.4 billion m3, and RMSE = 0.5 billion m3, which only account for 0.7% of the total water volume of Lake Qinghai. This study demonstrates that it is feasible to monitor comprehensively the fluctuation of large water bodies based entirely on remote sensing data. [ABSTRACT FROM AUTHOR]

Since the 1950s, the major gauging stations along the Yellow River have recorded a trend of decline in measured discharge. During the 1990s, the Yellow River once became seasonal and sent no water to the sea for several months in a year. This study investigates changes in the availability of water resources and water use at different sections of the Yellow River and in different economic sectors in the basin. Some hard and soft landing measures in dealing with basin closure are introduced and policy implications regarding the reallocation of water resources are addressed. [ABSTRACT FROM AUTHOR]

This paper investigates the existence of the Kuznets curve in industrial water use. The result shows that industrial water use in most countries in the Organization for Economic Cooperation and Development (OECD) has experienced an increase, followed by a leveling off and then a decrease to some extent as income rises. The relationship between changes in industrial water use and income appears to comply with the environmental Kuznets curve, i.e., an inverted U-shaped curve seen in the relationship between income changes and environmental quality. It is found that the income threshold corresponding to the turning point of industrial water use varies across the OECD countries with a majority falling in the range of 10,000 United States dollars (USD)/capita–25,000USD/capita (1995 constant prices). Further examination suggests that decrease in the share of the secondary industry in the national economy is a precondition for the stabilization and decline in industrial water use. In the OECD countries, the share of the secondary industry in total GDP was around 40% at the turning point of industrial water use. The verification of the existence of the Kuznets curve relationship in industrial water use and the identification of the share of the secondary industry in total GDP corresponding to the turning point help in projecting the scale of future increase in industrial water use in developing countries. [ABSTRACT FROM AUTHOR]

The drought episodes in the second half of the 20th century have profoundly modified the state of Lake Chad and investigation of its variations is necessary under the new circumstances. Multiple remote sensing observations were used in this paper to study its variation in the recent 25 years. Unlike previous studies, only the southern pool of Lake Chad (SPLC) was selected as our study area, because it is the only permanent open water area after the serious lake recession in 1973–1975. Four satellite altimetry products were used for water level retrieval and 904 Landsat TM/ETM+ images were used for lake surface area extraction. Based on the water level (L) and surface area (A) retrieved (with coinciding dates), linear regression method was used to retrieve the SPLC’s L-A curve, which was then integrated to estimate water volume variations (DV). The results show that the SPLC has been in a relatively stable phase, with a slight increasing trend from 1992 to 2016. On annual average scale, the increase rate of water level, surface area and water volume is 0.5 cm year-1, 0.14 km2 year-1 and 0.007 km3 year-1, respectively. As for the intra-annual variations of the SPLC, the seasonal variation amplitude of water level, lake area and water volume is 1.38 m, 38.08 km2 and 2.00 km3, respectively. The scatterplots between precipitation and DV indicate that there is a time lag of about one to two months in the response of water volume variations to precipitation, which makes it possible for us to predict DV. The water balance of the SPLC is significantly different from that of the entire Lake Chad. While evaporation accounts for 96% of the lake’s total water losses, only 16% of the SPLC’s losses are consumed by evaporation, with the other 84% offset by outflow. [ABSTRACT FROM AUTHOR]

In this study, a new parameterization scheme of evaporative fraction (EF) was developed from the contextual information of remotely sensed radiative surface temperature (Ts) and vegetation index (VI). In the traditional Ts - VI triangle methods, the Priestley-Taylor parameter Ø of each pixel was interpolated for each VI interval; in our proposed new parameterization scheme (NPS), it was performed for each isopiestic line of soil surface moisture. Specifically, Ø of mixed pixels was determined as the weighted-average value of bare soil Ø and full-cover vegetation Ø. The maximum Ts of bare soil (Tsmax) is the sole parameter needed as the constraint of the dry edge. This has not only bypassed the task involved in the determination of the maximum Ts of fully vegetated surface (Tcmax), but also made it possible to reduce the reliance of the Ts - VI triangle methods on the determination of the dry edge. Ground-based measurements taken during 21 days in 2004 were used to validate the EF retrievals. Results show that the accuracy achieved by the NPS is comparable to that achieved by the traditional Ts - VI triangle methods. Therefore, the simplicity of the proposed new parameterization scheme does not compromise its accuracy in monitoring EF. [ABSTRACT FROM AUTHOR]

We assessed the present and future climatologies of mean summer monsoon over South Asia using a high resolution regional climate model (RegCM4) with a 25 km horizontal resolution. In order to evaluate the performance of the RegCM4 for the reference period (1976-2005) and for the far future (2070-2099), climate change projections under two greenhouse gas representative concentration pathways (RCP4.5 and RCP8.5) were made, the lateral boundary conditions being provided by the geophysical fluid dynamic laboratory global model (GFDL-ESM2M). The regional climate model (RCM) improves the simulation of seasonal mean temperature and precipitation patterns compared to driving global climate model (GCM) during present-day climate conditions. The regional characteristic features of South Asian summer monsoon (SASM), like the low level jet stream and westerly flow over the northern the Arabian Sea, are well captured by the RegCM4. In spite of some discrepancies, the RegCM4 could simulate the Tibetan anticyclone and the direction of the tropical easterly jet reasonably well at 200 hPa. The projected temperature changes in 2070-2099 relative to 1976-2005 for GFDL-ESM2M show increased warming compared to RegCM4. The projected patterns at the end of 21st century shows an increase in precipitation over the Indian Peninsula and the Western Ghats. The possibilities of excessive precipitation include increased southwesterly flow in the wet period and the effect of model bias on climate change. However, the spatial patterns of precipitation are decreased in intensity and magnitude as the monsoon approaches the foothills of the Himalayas. The RegCM4-projected dry conditions over northeastern India are possibly related to the anomalous anticyclonic circulations in both scenarios. [ABSTRACT FROM AUTHOR]

Using National Oceanographic and Atmospheric Administration/Advanced Very High Resolution Radiometer (NOAA/AVHRR) and Climatic Research Unit (CRU) climate datasets, we analyzed interannual trends in the growing-season Normalized Difference Vegetation Index (NDVI) in China from 1982 to 2011, as well as the effects of climatic variables and human activities on vegetation variation. Growing-season (period between the onset and end of plant growth) NDVI significantly increased (p < 0.01) on a national scale and showed positive trends in 52.76% of the study area. A multiple regression model was used to investigate the response of vegetation to climatic factors during recent and previous time intervals. The interactions between growing-season NDVI and climatic variables were more complex than expected, and a lag existed between climatic factors and their effects on NDVI. The regression residuals were used to show that over 6% of the study area experienced significantly human-induced vegetation variations (p < 0.05). These regions were mostly located in densely populated, reclaimed agriculture, afforestation, and conservation areas. Similar conclusions were drawn based on land-use change over the study period. [ABSTRACT FROM AUTHOR]

An interval-parameter fuzzy linear programming with stochastic vertices (IFLPSV) method is developed for water resources management under uncertainty by coupling interval-parameter fuzzy linear programming (IFLP) with stochastic programming (SP). As an extension of existing interval parameter fuzzy linear programming, the developed IFLPSV approach has advantages in dealing with dual uncertainty optimization problems, which uncertainty presents as interval parameter with stochastic vertices in both of the objective functions and constraints. The developed IFLPSV method improves upon the IFLP method by allowing dual uncertainty parameters to be incorporated into the optimization processes. A hybrid intelligent algorithm based on genetic algorithm and artificial neural network is used to solve the developed model. The developed method is then applied to water resources allocation in Beijing city of China in 2020, where water resources shortage is a challenging issue. The results indicate that reasonable solutions have been obtained, which are helpful and useful for decision makers. Although the amount of water supply from Guanting and Miyun reservoirs is declining with rainfall reduction, water supply from the South-to-North Water Transfer project will have important impact on water supply structure of Beijing city, particularly in dry year and extraordinary dry year. [ABSTRACT FROM AUTHOR]

Potential assessment of water resources development (PAWRD) is very important for regional water management, water allocation, water transfer and economic planning, especially for today's China, which is under a rapid economic growth, a continued expansion of population, and an increasingly deteriorating eco-environment. In this work, the southern part of Haihe River (SPHR) is selected as the representative area of the North China Region for a case study based on considerations such as available data, geographic characteristics, administrative boundaries, and the state of water shortage. A growth pattern of regional water resources development is presented. A fuzzy assessment model is established and applied to determine the growth stage, an indicator for water resources development potential. Seven assessment factors, selected based on the conditions of supply, demand, and use efficiency of water subjected to the regional physical, social, and economic settings, include irrigation rate of arable land,, exploitation rate of water resources, the water-saving level, a water supply and demand modulus, the water supply per capita, and the ratio of eco-environmental water use. These factors are integrated into the fuzzy assessment model, which is shown to be capable and effective for potential assessment. The assessment results demonstrate the potential of water resources development is little in SPHR and are substantiated by the necessity of the middle route of the South-North Water Transfer (SNWT) in the long run. It is also suggested at present that promoting water saving and strengthening water demand controls would be the most feasible and effective solution to mitigate water shortage stress of SPHR before the SNWT scheme is implemented. PA WRD provides a scientific tool for water-demand management and water-saving improvement, as well as a necessary basis for decision- making for economy planning and water transfer design. [ABSTRACT FROM AUTHOR]