Water Transfer Research Articles

Scalable MXene/Sepiolite film-based hydrovoltaic generators with outstanding output power

Harvesting energy from the ambient environment via hydrovoltaic effect is an emerging technology for environmentally friendly and sustainable power generation. However, its practical utilization has been hindered by the lack of scalable electrode materials with high output power. Here, novel MXene/Sepiolite composite films with scalable surface areas were designed and fabricated using highly concentrated MXene/Sepiolite ink via Meyer rod-coating, which showed promising performance used for transpiration-driven electrokinetic power generators (TEPGs). This was owing to the confined water and ion transfer in the composite films. The added Sepiolite could substantially adjust the layer spacing and hydrophilicity of the films, resulting in boosted performance. The MXene/Sepiolite composite films showed composition, size, and electrolyte-dependent power generator performance due to the controlled mass transfer in the films, producing TEPGs with tunable output power. An MXene/Sepiolite-based TEPG (MSTEPG) could generate a short-circuit current (ISC) of 163.82 μA in 1.75 wt% NaCl solution, demonstrating a maximum output power of 70.68 μW, which was larger than most reported TEPGs. This simple yet efficient roll-to-roll strategy provided a promising way for fabricating MXene-based electrodes on a large scale and represented a critical step toward the practical utilization of massive energy produced by the hydrovoltaic effect.

Numerical modeling of biophilic design incorporating large-scale waterfall into a public building: Combined simulation of heat, air, and water transfer

Biophilic design, which integrates nature into built environments, fosters beneficial human–nature interactions. It has gained traction as a promising solution to achieve a better trade-off between sustainability and occupants' well-being. However, despite its potential, quantitative assessment of biophilic design, particularly water elements, remains limited. This study addresses this gap using a two-step approach that quantifies the effects of biophilic water design on indoor hygrothermal conditions. We first developed a numerical model that couples building energy simulations with computational fluid dynamics to accurately predict the heat, air, and water transfer phenomena caused by waterfalls and ponds, and a novel mathematical model that precisely calculates water evaporation using water potential as the driving force of moisture transfer. Then, using this proposed method, we performed a numerical analysis of an actual public building as the reference space. This analysis quantitatively evaluated the effects of water elements on a hygrothermal environment and their impact on energy conservation. A series of comparisons and discussions based on the simulation results demonstrated the model's capability to accurately simulate the hygrothermal environment influenced by waterfalls and ponds. Moreover, the study confirmed and quantified the effects of waterfalls, specifically its significant evaporative cooling effect during summer, humidifying effect in winter, and heat load reduction benefits. These findings enrich our understanding of the impacts of biophilic water design on indoor environments and energy conservation, thereby contributing to the optimization of biophilic design practices.

Ligand extension of aluminum fumarate metal-organic framework in transferring higher water for adsorption desalination

This article presents the synthesis and characterization of a new microporous metal organic framework (MOF) for adsorption desalination for the first time. The new MOF, designated as “Al-t,t-Ma”, is an analogue of aluminum fumarate (Al-Fum) and is fabricated via ligand extension method. Firstly, the MOF is synthesized, and then characterized by XRD, FTIR spectroscopy, TEM, SEM, TGA and N2 adsorption techniques. Secondly, the water adsorption experiments on the pristine Al-Fum and Al-t,t-Ma are performed for a wide temperature (30 °C ≤ T ≤ 80°C) and pressure (0 < P/Ps ≤ 0.9) ranges. The water adsorption isotherms, kinetics, hydro-thermal stabilities as well as the isosteric heat of adsorption (Qst) are evaluated. Thirdly, based on the experimentally confirmed isotherms, kinetics and isosteric heats data, the adsorption assisted desalination (AD) system is modelled and simulated. Finally, the performances of AD system employing Al-Fum and Al-t,t-Ma MOFs are calculated in terms of the performance ratio (PR) and specific daily water production (SDWP) under various half cycle times (100 s ≤ tcycle ≤ 1000 s) and regeneration temperatures (55°C ≤ Tregen ≤ 80°C). As compared with the pristine Al-Fum, the pore volume of Al-t,t-Ma MOF is found 115 % higher. The proposed Al-t,t-Ma MOF possesses higher water transfer (+57.5 % more) with promising hydro-thermal stability. Employing Al-t,t-Ma MOF as porous adsorbent, the SDWP is achieved 28 m3 per tonne of MOFs per day at the regeneration temperature of 55°C. These results confirm that Al-t,t-Ma MOF is a competent candidate for adsorption desalination.

Influence of Water Transfer between River Basins on the Operation of Water Systems in Semi-arid Regions

Influence of Water Transfer between River Basins on the Operation of Water Systems in Semi-arid Regions

Research progress on operation control and optimal scheduling of irrigation canal systems

AbstractOpen canals are a common water transfer method used in water transfer projects and agricultural irrigation and drainage projects. With the emergence of drawbacks in traditional canal control models and the increasingly severe shortage of water resources, accurate transport and distribution of water in the canal system of the irrigation district, rational allocation of water resources, reduction in water loss, improvement in the efficiency and benefit of water resource utilization, and satisfaction of the water demand of different water users are needed. Many scholars have conducted extensive research on canal operation control and optimal scheduling. This paper systematically reviews and summarizes the relevant research progress, including the theory of unsteady flow in open canals, the operation mode of the canal system, the operation control model and algorithm of canal systems, and the optimization of water distribution in canal systems. By summarizing the research progress already achieved, the existing problems and future development directions are identified according to actual needs, providing a reference for the ongoing modernization of irrigation districts and the research and application of digital twin irrigation district technology.

Effect of the Fe2O3/SBA-15 Surface on Inducing Ozone Decomposition and Mass Transfer in Water

Effect of the Fe2O3/SBA-15 Surface on Inducing Ozone Decomposition and Mass Transfer in Water

Combining mathematical models and machine learning algorithms to predict the future regional-scale actual transpiration by maize

Plants on the land surface play a vital role in the hydrological water cycle as they transport soil water to the atmosphere through transpiration. Root water uptake (RWU) is considered a crucial step in this process as it is the first stage of transpiration, directly determining the actual transpiration (Ta) of plants. However, accurately measuring RWU or Ta in situ poses significant challenges. Here, we establish an overall approach of combining mathematical models and machine learning algorithms to obtain high-precision (500 m×500 m) regional-scale daily Ta maps for various future climate patterns. The Hydrus-1D and AquaCrop models were employed to calculate the total RWU fluxes across the entire root zone, aiming to achieve Ta at a point scale. A machine learning model was developed using the CatBoost algorithm and environmental covariates extracted from the Google Earth Engine (GEE) platform to upscale these point-scale Ta to the regional scale. Furthermore, a total of 22 CMIP6 Earth System Models (ESMs) were evaluated, and among them, ACCESS-CM2 and ACCESS-ESM1–5 were selected for simulating future climate scenarios. Based on the established machine learning model and selected ESMs, regional-scale Ta maps were generated from 2020 to 2100 for the SSP245 and SSP585 (Shared Socioeconomic Pathways) scenarios. The results indicate that near-surface specific humidity, mean near-surface air temperature, latitude, and surface downwelling shortwave radiation are the critical factors influencing regional-scale Ta. As greenhouse gas emissions intensify and temperatures rise, regional-scale Ta is enhanced, leading to an accelerated transfer of soil water to atmospheric water. Under the SSP245 scenario, Ta increases on average by 0.55–1.16 % every 20 years, with its incremental value ranging from 7.14∙10−4 to 8.65∙10−4 cm day−1, while under the SSP585 scenario, Ta increases more significantly, achieving an average increase of 0.64–1.81 % every 20 years, with its incremental value ranging from 1.595∙10−3 to 2.821∙10−3 cm day−1. This study provides a robust integrated approach to assess the future regional-scale Ta providing valuable insights into the underlying water cycle mechanisms and regional water requirements for future climate scenarios.

A Network Governance Model for Enhancing Socially Responsible Collective Action in Mega Water Transfer Projects

A Network Governance Model for Enhancing Socially Responsible Collective Action in Mega Water Transfer Projects

Synergistic ionic liquid encapsulated MIL-101 (Cr) metal-organic frameworks for an innovative adsorption desalination system

The transformations of brackish water into freshwater employing porous materials such as metal-organic frameworks (MOFs) show a great potential for a green environment. But the adsorption-based desalination slows down due to slow water adsorption/desorption rates and inadequate water storage capacity in conventional adsorbents. Therefore, the restructuring of porous MOFs increases water storage and transfer rates. This paper presents a comprehensive investigation on the fabrication of ionic liquid encapsulated MIL-101 (Cr) MOFs (metal-organic frameworks), and its interactions with water for desalination applications. Firstly, the pristine MIL-101 (Cr) is encapsulated with various types/amounts of ionic liquids. Next, these MOFs are characterized via SEM (Scanning electron microscope), FTIR (Fourier transform infrared), XRD (X-ray diffraction), TGA (Thermal gravimetric analysis), N2 adsorption techniques. The water adsorption on these MOFs is performed experimentally for a wide temperature (30–80 °C) and pressure (0 < P/Ps < 0.95) ranges. The effects of the size (or type) as well as the encapsulation ratio of ionic liquids on water adsorption behaviors are conducted. Based on the experimentally proven water adsorption (isotherms and kinetics) data, an AD (adsorption desalination) system is modelled and simulated. Finally, the AD performances in terms of the specific daily water production (SDWP) and performance ratio (PR) are parametrically studied with respect to various regeneration temperature (50–80 °C) and cycle times (100 s–1000 s). It is found that by ionic liquid encapsulation, the water uptakes/offtake rates are expedited up to 48% (for adsorption)/55% (for desorption), respectively. In addition, the water transfer (Δq) improves up to 45% more than the parent MIL-101(Cr) MOFs. Furthermore, the SDWP increases from 38 to 56 m3 of water per tonne of MOFs per day at the regeneration temperature of 70 °C. The simulation results also show that the ionic-liquid-encapsulated MIL-101 (Cr) MOFs generates water (>25 m3 water per tonne of IL-MOFs) at the regeneration temperature of 50 °C and is potential for the next generation desalination applications.

Transport numbers of ion-exchange membranes in ternary mixtures of KCl, H2O and ethanol relevant for electrodialysis and desalination processes

Understanding the transport phenomena in electrolyte mixtures involved in electrochemical processes is of utmost importance for the modelling and improvement of battery technology, fuel cells, ion-exchange membrane processes, and much more. In this work, we derive relations and present methods for the analysis of electric potential measurements of concentration cells and ion-exchange membrane permselectivity with ternary mixtures of KCl, H2O and ethanol (EtOH). Measurements of electric potentials across the Selemion CMVN (cation-exchange) and AMVN (anion-exchange) membranes in this ternary mixture suggest that the presence of EtOH affects the membrane permselectivity, but that the transference of EtOH is zero; i.e., ta=0. Instead, the decrease in membrane permselectivity can be explained by a varying water transference coefficient, tw. In the absence of EtOH we find tw≈4 in both membranes, and that the decrease in tw is proportional to the average thermodynamic activity of EtOH in mixtures adjacent to the membranes. The membranes were also found to be charge selective, as quantified by the ionic transport numbers; i.e., tK+=1 for the Selemion CMVN and tK+=0 for the Selemion AMVN. The presented method can readily be extended and leveraged to determine transference coefficients in other electrochemical systems.

Spatial differentiation and influencing factors of effective phosphorus in cultivated soil in the water source area of the mid-route of South-to-North water transfer project.

The long-term application of phosphate fertilizers in agricultural production leads to a large accumulation of phosphorus in the soil. When it exceeds a certain limit, phosphorus will migrate to surrounding water bodies through surface runoff and other mechanisms, potentially causing environmental risks such as eutrophication of water bodies and increasing the risk of water source pollution. This study takes Shiyan City, the water resources area of the mid-route of the South-to-North Diversion Project (MSDP), as the study area. Based on 701 sampling points of topsoil, geostatistics and geodetectors were used to explore the spatial heterogeneity and influencing factors of available phosphorus (AP) in the topsoil of the area. The results show that the effective phosphorus content in the topsoil of the study area ranges from 0.30 to 146.00 mg/kg, with an average value of 14.28 mg/kg, showing strong variability characteristics. Geostatistical analysis shows that among all theoretical models, the exponential model has the best fitting effect, with a lump gold effect of 0.447 and a range of 82,000 m. The soil available phosphorus content shows an increasing trend from the Central Valley lowlands to the surrounding mountainous hills. Among them, elevation is the main controlling factor for the spatial variation of available phosphorus in the topsoil, followed by soil types, planting systems, annual precipitation, and organic matter. The non-linear enhancement or dual-factor enhancement among various environmental factors reveals the diversity and complexity of spatial heterogeneity affecting available phosphorus content in cultivated soil. This study could provide scientific references for maintaining ecological security in the water source area of the MSDP, improving the precise management of AP, and enhancing cultivated land quality.

Deteriorating wintertime habitat conditions for waterfowls in Caizi Lake, China: Drivers and adaptive measures

China has made enormous strides to achieve high-quality development and biodiversity conservation, and the establishment of nature-protected areas is one of the essential initiatives. Caizi Lake involves a natural reserve and two national wetland parks, accommodating winter migratory waterfowl over the middle and lower Yangtze River basin in China. However, the water transfer from the Yangtze River to the Huai River (YR-HR water transfer) has modified the winter hydrological conditions of Caizi Lake, negatively affecting wintertime waterfowl habitats. Hence, conserving wintertime waterfowl habitats necessitates knowledge of the dynamical mechanisms behind the impacts of YR-HR water transfer on wintertime waterfowl habitats and adaptive measures. Here we developed a machine learning model, the normalized difference vegetation index, and on-spot observatory datasets such as the spatial distribution of waterfowl species and underwater topography of Caizi Lake. We found that the rising winter water level of Caizi Lake encroaches on winter waterfowl habitat with extremely high suitability. Meanwhile, rising water levels reduced waterfowl food sources. Thus, rising water levels due to YR-HR water transfer deteriorated waterfowl living conditions over Caizi Lake. Therefore, we proposed adaptive measures to alleviate these negative effects, such as water level regulation, artificial feeding of waterfowls, restoration and reconstruction of contiguous mudflats, grass flats. This study highlights human interferences with waterfowl habitats, necessitating biodiversity conservation at regional scales.

A Harmony-Based Approach for the Evaluation and Regulation of Water Security in the Yellow River Water-Receiving Area of Henan Province

Water security, as a crucial component of national security, plays a significant role in maintaining regional stability and ensuring the healthy and rapid development of the economy and society. The Yellow River water-receiving area of Henan Province (YRWAR-HN) is selected as the research area in this study. Firstly, a comprehensive evaluation index system is constructed based on the actual water security problems of the research area, and the single index quantification–multiple indices syntheses–poly-criteria integration method (SMI-P) is introduced to quantify the water security degree of 14 cities in the YRWAR-HN from 2010 to 2021. Then, the obstacle degree model is used to identify the key obstacle indexes that restrict the improvement of water security. Finally, the harmonious behavior set optimization method is adopted to carry out the regulation of water security, and the improvement path of water security in the YRWAR-HN is formulated. The results indicate the following: (1) the water security degree of the YRWAR-HN shows a fluctuating upward trend, increasing from 0.4348 (2010) to 0.6766 (2021), a significant rise of 55.61%. The water security level improves from the relatively unsafe level to the relatively safe level. Hebi City exhibits the fastest rate of water security improvement, while Xinxiang City shows the slowest rate. (2) The density of the river network (X1) and the proportion of investment in water conservancy and environmental protection in the total investment (X15) are the two indexes with the highest obstacle degree, with the average obstacle degrees being 15.09% and 10.79%, respectively. (3) The combination of the composite regulation scenario and improvement Path 2 is the optimal regulation strategy for water security in the YRWAR-HN. From the implementation process, Luoyang, Sanmenxia, Jiyuan, Xuchang, and Shangqiu may prioritize improving their flood and drought disaster defense capabilities and emergency response capabilities, continuously enhancing the flood prevention and disaster reduction system. Zhengzhou, Kaifeng, Xinxiang, Jiaozuo, Anyang, Hebi, Pingdingshan, and Zhoukou may prioritize resolving the regional water supply and demand conflicts, balancing development and conservation, actively seeking transboundary and external water transfers, and strengthening the capacity for water conservation and intensive utilization. Puyang City may prioritize enhancing its comprehensive water environment management capabilities, increasing investment in water conservancy and the environment, improving production processes, reducing pollutant emissions, and mitigating agricultural non-point source pollution.

An Attribution Analysis of Runoff Alterations in the Danjiang River Watershed for Sustainable Water Resource Management by Different Methods

Determining the relative roles of climatic versus anthropogenic factors in runoff alterations is important for sustainable water resource utilization and basin management. The Danjiang River watershed is a crucial water resource area of the middle route of the South-to-North Water Transfer Project. In this study, four widely used quantitative methods, including the simple linear regression, the double mass curve, the paired year with similar climate conditions, and an elasticity method based on the Budyko framework were applied to detect the relative contribution of climatic and anthropogenic factors to runoff variation in the Danjiang River watershed. The calculation processes of each method were systematically explained, and their characteristics and applications were summarized. The results showed that runoff decreased significantly (p &lt; 0.05) with an average change rate of −3.88 mm year−1 during the period of 1960–2017, and a significant change year was detected in 1989 (p &lt; 0.05). Generally, consistent estimates could be derived from different methods that human activity was the dominant driving force of significant runoff reduction. Although the impacts of human activity estimated by the paired year with similar climate conditions method varied among paired years, the other three methods demonstrated that human activity accounted for 80.22–92.88% (mean 86.33%) of the total reduction in the annual runoff, whereas climate change only contributed 7.12–19.78% (mean 13.67%). The results of this study provide a good reference for estimating the effects of climate change and human activities on runoff variation via different methods.

Ecological impacts and supply demand evolution of the Yangtze to Huaihe water transfer project in Anhui section

Human activities have profound impacts on land use and the supply–demand balance of ecosystem services (ESs). Various activities, such as urban construction, urban and rural planning, and inter-basin water transfer projects, continuously reshape land use patterns. This is a case study of the Anhui section of the Yangtze-Huaihe Water Diversion Project. Data from 2000, 2010, and 2020 is analyzed. Additionally, the patch-generating land use simulation (PLUS) model is utilized to quantify the specific impacts of the water diversion project construction on the supply and demand of ESs. The results indicate that the comprehensive dynamic attitude of land use during the project construction period significantly increased, rising from 0.16 to 13.79%, and mainly affected forest, water areas, construction land, and unused land. Specifically, the construction of the project led to significant changes in water purification, biodiversity, and, especially, hydrological regulation services. Additionally, the migration of residents significantly impacted the demand for ESs. The study also found a significant correlation between land use changes and the balance of ES supply and demand: the proportion of cultivated land and construction land is positively correlated with the balance, while the proportion of forest, grassland, and water areas is negatively correlated. This study provides empirical data for understanding the environmental and socio-economic impacts of large-scale water diversion projects and offers a scientific basis for local mitigation and control of adverse impacts. Through quantitative analysis and model prediction, this research effectively bridges the gap between theory and practice, providing important references for sustainable regional development.

A framework for seasonal groundwater banking in agricultural regions: A case study

Groundwater banking has been used for demand-oriented management of groundwater resources in semi-arid and arid regions. This paper aims to propose a new framework for seasonal groundwater banking. In this framework, crop production functions are used to estimate users' bid packages representing the price of each unit volume of water in each auction period. The bid packages, along with users' water rights, are considered inputs of an optimization model, which maximizes the profit of users participating in the groundwater bank. The main outputs of the optimization model are the volumes of exchange and storage of water, as well as the water price in the auction periods. The efficiency of the proposed framework has been evaluated by applying it to the Nough region in the Rafsanjan Plain, central Iran. An existing plan for inter-basin water transfer to this region is also considered in the water banking framework. The results illustrate that the total annual profit of all users after the establishment of the bank compared to the status quo has increased up to 43.8 %. The profit of the water-recipient basin has also increased more than 4 times compared to the existing condition. In addition, water banking with a water transfer system increases the economic productivity of water and crop production by 37.32 % and 22.41 %, respectively.

A practical method for the in-situ estimation of the effective thermal resistance of gas diffusion layers in PEMFC

The membrane electrode assembly of a PEM fuel cell is hotter than the gas feeding plates because heat is generated within it, and the diffusion layers are thermally resistive. The temperature gradient created, which increases as a function of the current density, is useful for evacuating the water produced in vapor form. This water transport mechanism is known as the “heat pipe effect”. The temperature gradient produces a saturation vapour pressure gradient, which in turn produces a diffusive vapor flow. Mastering water management, coupled with heat management, requires knowledge of the temperature of the MEA and therefore the effective thermal resistance of the diffusion layers. In this paper, we present an original method for estimating this thermal resistance in situ, without using heat flux sensors or directly measuring the temperature of the MEA. The method requires the ability to impose a temperature gradient between the anode and cathode plates, and to perform a hot-side water balance. Thermal resistance is deduced from the coupling between heat and water transfer. Two diffusion layers widely used by the community are tested. The GDL Sigracet 22 BB (from SGL Carbon) has a lower effective thermal resistance than the GDL Freudenberg H15C14. Variations in these thermal resistances are measured as a function of the temperature gradient imposed and of the compression ratio.

Drivers of richness and abundance of parasites of fishes from an intermittent river before and after an interbasin water transfer in the Brazilian semi-arid region.

This study examined the metrics of the macroparasite community in fishes from the Jaguaribe River basin, state of Ceará, before and after receiving water from the São Francisco River in Northeastern Brazil. This research assessed the association of environmental factors (water parameters) and the traits of 30 fish species on the parasite richness and abundance across space (river course) and time (seasons, pre- and post-transposition periods). Generalized linear models reveal associations between parasite metrics and host traits, water parameters, and river sub-basin. Host size and body condition positively correlated with parasite richness and abundance, while reproductive phase was negatively related. Water quality impacted ecto- and endoparasites differently, with seasonal and sub-basins variations and differences among sub-basins. The general models also indicate that the period is a significant variable, where parasite richness decreases while abundance increases in the post-transposition period. This study underscores the importance of considering diverse environmental and host variables for understanding parasite dynamics in river ecosystems. These findings could lead to valuable insights for ecosystem management and conservation, elucidating the potential consequences of environmental alterations on parasite-host interactions and ecosystem health.

Insights to ballast water: metagenomics as a pressing priority

Metagenomics represents a pivotal development in genomics, offering unprecedented insights into a diverse spectrum of microorganisms, including bacteria, viruses, and fungi, that were previously challenging or impossible to study outside natural environments. Its applications span a remarkable range, from exploring cosmic entities to the depths of our oceans, incorporating numerous analyses. Yet, its utilization in the context of ballast water analysis remains scarce. This highlights the crux of the present review, which aims to showcase the need for metagenomics in ballast water analysis. As is known, ballast water is essential for maintaining ship stability under no cargo conditions or during adverse weather, with daily global movements estimated to be between 3 to 10 billion tonnes. A single bulk cargo ship can transport up to 60,000 tonnes of ballast water for a 200,000-tonne load. It is estimated that over 7,000 species are transported globally in ships' ballast water daily, posing significant ecological risks when these organisms are discharged into new environments where they can become invasive species, disrupting local ecosystems, economies, and human health. Despite the International Maritime Organization setting D-2 standard guidelines and endorsing several ballast water management practices for its safe discharge, the issue persists. This underscores the necessity of employing metagenomics to enhance the monitoring of microbial content in ballast water. The review summarizes some research conducted worldwide to analyze ballast water by metagenomics, all exhibiting diverse microbes, including potent pathogenic bacterial and viral forms. The findings support our view, making metagenomics an invaluable tool to monitor ballast water treatment effectiveness in compliance with evolving environmental regulations. Though the challenges facing metagenomic applications—namely cost, complexity, and the need for comprehensive reference databases—are significant, they will surely be surmountable considering continual technological and methodological advancements. Embracing metagenomics offers a pathway to not only address the ecological threats posed by ballast water transfers but also to safeguard the future of global shipping industries.

A dataset of spatial-temporal water color variations in regulating reservoirs of Jiaodong Water Transfer Project during 1990&amp;ndash;2022

A dataset of spatial-temporal water color variations in regulating reservoirs of Jiaodong Water Transfer Project during 1990&amp;ndash;2022