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Experimental methods capable of selectively probing water at the DNA minor groove, major groove, and phosphate backbone are crucial for understanding how hydration influences DNA structure and function. Chiral-selective sum frequency generation spectroscopy (chiral SFG) is unique among vibrational spectroscopies because it can selectively probe water molecules that form chiral hydration structures around biomolecules. However, interpreting chiral SFG spectra is challenging since both water and the biomolecule can produce chiral SFG signals. Here, we combine experiment and computation to establish a theoretical framework for the rigorous interpretation of chiral SFG spectra of DNA. We demonstrate that chiral SFG detects the N–H stretch of DNA base pairs and the O–H stretch of water, exclusively probing water molecules in the DNA first hydration shell. Our analysis reveals that DNA transfers chirality to water molecules only within the first hydration shell, so they can be probed by chiral SFG spectroscopy. Beyond the first hydration shell, the electric field-induced water structure is symmetric and, therefore, precludes chiral SFG response. Furthermore, we find that chiral SFG can differentiate chiral subpopulations of first hydration shell water molecules at the minor groove, major groove, and phosphate backbone. Our findings challenge the scientific perspective dominant for more than 40 years that the minor groove "spine of hydration" is the only chiral water structure surrounding the DNA double helix. By identifying the molecular origins of the DNA chiral SFG spectrum, we lay a robust experimental and theoretical foundation for applying chiral SFG to explore the chemical and biological physics of DNA hydration. [ABSTRACT FROM AUTHOR]

Aggregation-induced emission (AIE) is an effective strategy for improving the photoluminescence (PL) performance of metal nanoclusters (MNCs). However, the origin of AIE in MNCs is still not fully understood, which is pivotal for the design of AIE luminogens (AIEgens). Here, water soluble silver nanoclusters (Ag NCs) with AIE properties were synthesized. These as-synthesized non-luminescent Ag NCs will become photoluminescent when transferred from water to ethanol, and the emission peak was redshifted from ∼560 to ∼600 nm and largely intensified with the addition of Cu2+. The addition of Cu2+ makes a big difference in the PL properties of Ag NCs. That is, the PL will be enhanced if Cu2+ is added with the sequence "Ag NCs + Cu2++EtOH." In contrast, the PL will be quenched if Cu2+ is added with the sequence "Ag NCs + EtOH + Cu2+." The PL was from the supramolecular clusters formed by the assembly of capping ligands on the confined surface of individual silver clusters through weak interactions. The addition of Cu2+ could regulate the assembly structure and further affect the energy lever (p-band) through space electron interactions. These results provide new insights into the AIE process in metal nanoclusters. [ABSTRACT FROM AUTHOR]

Solar‐driven water evaporation is considered as the sustainable approach to alleviate freshwater resource crisis through direct use of solar energy. However, it is still challenging to achieve the multifunctional solar evaporators equipped with both high evaporation and purification performance to handle practical complex wastewater. Here, a simple and cost‐effective multifunctional 3D solar evaporator is prepared by alternately decorating the commercial sponge with FeOOH quantum dots (FQDs) supported MXene sheets composites and chitosan hydrogel coatings for enabling the solar water evaporation and organic wastewater photodegradation simultaneously. MXene composites allow the solar evaporator with excellent photothermal conversion performance, the hydrophilic chitosan hydrogel coated interconnecting skeleton structures of sponge serve as the mass transfer and water transport channels. The Fenton‐catalytic FQDs anchored on the MXene sheets surface accept the photo‐generated electrons of MXene sheets to induce the organic pollutant photo‐Fenton degradation reaction under sunlight irradiation. The resulting evaporator possesses both excellent water evaporation rate of 2.54 kg m−2 h−1 and high degradation efficiency (99.24% for methylene blue), coupled with durable salt‐resisting performance during long‐term seawater desalination (20 wt.% NaCl). This work provides a simple and feasible strategy for designing multifunctional solar evaporators to meet the potential application scenarios in practice. [ABSTRACT FROM AUTHOR]

When the water content of a porous material is high, air entrapped in the pore space is expected to affect water transfer through the pores. To understand the effects of air entrapment on water transfer in porous building materials in the high-water-saturation region, we examined the water transfer characteristics corresponding to significantly small air entrapment effects. First, we conducted two sets of water uptake experiments. In the first experiment, using three building materials, the time evolution of the amount of water absorption was measured at a low air pressure near vacuum (several kPa). In the second experiment, the water content profile during water uptake was measured using the gamma-ray attenuation method. The experimental results showed that low air pressure accelerated the water uptake by the brick and aerated concrete specimens, whereas water uptake by the calcium silicate board specimens was not significantly affected. These differences among materials were analyzed from a pore structure viewpoint. Moreover, gamma-ray attenuation measurements confirmed that the obtained water content profile was qualitatively similar at atmospheric and low air pressures, although the low air pressure increased both the water content of the material after capillary absorption and the wetting front propagation rate. Finally, simultaneous water and air transfer calculations based on the air and liquid water balance in a material reproduced the measured water absorption rates well, confirming that air entrapment and pressure development in the pores can significantly reduce the rate of water uptake and water content after capillary absorption. The calculation results also indicated that the air pressure in a material did not significantly increase at early water uptake stages where local water content was not high, which supported the general assumption that treating the liquid-water transfer in porous building materials as a one-component flow is valid in most cases. [ABSTRACT FROM AUTHOR]

Autochthonous dissolved organic matter (Auto-DOM) produced by a biological carbon pump using dissolved inorganic carbon (DIC) from carbonate weathering plays an important role in carbon cycling within inland waters. However, little is known regarding how environmental conditions impact the composition and fate of organic matter, especially in surface waters of the semi-arid Loess Plateau, which is enriched in DIC by significant carbonate weathering. To obtain novel insight, we combined hydrochemistry, isotopic composition (δ2H, δ18O, and δ13C DIC), Rayleigh fractionation model, optical spectroscopy (absorbance and fluorescence), and Fourier transform ion cyclotron resonance mass spectrometry measurements to elucidate how primary production and hydrology impact the composition of DOM and the stability of the resulting Auto-DOM throughout the river–reservoir–wetland aquatic continuum of the Bahe River in the carbonate-mineral-rich semi-arid Loess Plateau where carbonate weathering is significant. The Rayleigh fractionation model results indicated that watershed DIC is primarily consumed through aquatic primary production rather than CO 2 degassing. Further investigation revealed that primary production and evaporation co-occurred in this watershed. With the enrichment of the stable water isotope δ2H, the relative abundances of the allochthonous compounds decreased and the relative abundances of the autochthonous substances increased, suggesting that the terrestrial signal of riverine DOM decreased while autochthonous production increased along the flow pathway. In addition, associations between optical and molecular characteristics among DOM samples from different water bodies revealed that the stability ratio (Fmax(C2/(C2 + C4))) of Auto-DOM to the ratio of carboxylic-rich alicyclic molecules showed a consistent trend, suggesting that phytoplankton-derived and biomineralized C2 compounds are potentially recalcitrant DOM in inland waters. We conclude that hydrology and primary production affect the source, composition, and, potentially, the stability of DOM in DIC-enriched surface waters of the semi-arid Loess Plateau, which may lead to a more humic-like DOM composition in inland water and export this lower bioavailability DOC to the ocean in the long term. [ABSTRACT FROM AUTHOR]

Flow boiling heat transfer is a promising technology for thermal management. In this paper, flow boiling heat transfer characteristics in a rectangular vertical flow channel are experimentally and numerically investigated at low flow rate. Visualization results provide guidance for the prediction of flow patterns. The flow boiling correlation at low flow rates is improved with an error of less than 30%. Numerical results reveal vortices enhanced local heat transfer. Absolute vorticity is introduced to quantify the secondary flow. The results indicate that the secondary flow intensity increases with heat flux, verifying that boiling flow produces the local convection enhancement. [ABSTRACT FROM AUTHOR]

This paper examines the bordering and debordering deployment of water infrastructures on the Islands of Kinmen. Located less than 5 km off the coast of China, yet 200 km from their governing authority, Taiwan, Kinmen holds a critical position in cross-strait relations, and its water infrastructures have carried opposite political intentions. The 2018 Fujian-Kinmen water transfer pipeline serves as a debordering tool as it showcases that the People’s Republic of China could offer benefits to the people on the islands. In contrast, Kinmen’s existing water infrastructure, established during the Cold War, served as part of the bordering campaign to counter Communist China, as it represented progress and modern living under the government of the Republic of China (Taiwan). However, rather than assuming the successful deployment of infrastructure or a passive role of the islands, this paper highlights that the planning and construction of Kinmen’s water infrastructures were influenced by conditions of militarisation, shifting cross-strait relations, the islands’ socio-material constraints and their relationships with Taiwan and China. The case of Kinmen illustrates the capacity of water infrastructure to serve bordering and debordering purposes, as well as how other factors disrupt or facilitate these processes. [ABSTRACT FROM AUTHOR]

This article aims to investigate the hall current consequences on the transfer of clean water containing silver in addition to copper nanoparticles suspended nanofluids through vertical rotating channel. Boussinesq approximation is taken into consideration. Exact analytical solutions of governing equations subject to physical boundary conditions are obtained using the techniques of non‐dimensionalization. The impacts of Grashof number, radiation parameter, Prandlt number, frequency parameter, magnetic parameter, Hall parameter, parameter of rotation and its effects on primary as well as secondary velocity and temperature profiles are presented graphically. We analyze the Hall effects and mixed convection in magnetohydrodynamic (MHD) flow of nanofluids through a vertical rotating channel, based on extensive research and applications. An analytical approach is used to derive the exact solution to this problem. A comparative study for silver and copper nanoparticles is made. A tabular solution for impacts of said parameters on convection rate and skin friction coefficient is also presented. This study is applicable for geophysical dynamics and engineering applications. [ABSTRACT FROM AUTHOR]

This study aims to assess the efficacy of machine learning models in predicting solute concentration (C) distribution in a membrane separation process, using the input parameters which are spatial coordinates. Computational fluid dynamics (CFD) was employed with machine learning for simulation of process. The models evaluated include Kernel Ridge Regression (KRR), Radius nearest neighbor regression (RNN), K-nearest neighbors (KNN), LASSO, and Multi-Layer Perceptron (MLP). Additionally, Harris Hawks Optimization (HHO) was utilized to fine-tune the hyperparameters of these models. Leading the way is the MLP model, which achieves a remarkable test R2 value of 0.98637 together with very low RMSE and MAE values. Strongness and generalization capacity are shown by its consistent performance on test and training datasets. To conclude, the effectiveness of using machine learning regression methods more especially, KRR, KNN, RNN, LASSO, and MLP in estimating concentration from spatial coordinates was demonstrated in this work. For separation science via membranes where predictive modeling of spatial data is essential, the results offer important new perspectives by developing hybrid model. [ABSTRACT FROM AUTHOR]

Seomijn River Basin has numerous hydraulic structures designed to satisfy water demands and mitigate future droughts. However, the increasing water demand and export to neighboring areas cause water deficits and conflicts between water users. Therefore, practical strategies to mitigate the potential damage from climate change are essential. In this study, we aimed to propose practical strategies under climate change by examining the future water security of the Seomjin River Basin under five different water allocation scenarios referenced from the practical policies of various countries. Future climate models determined based on extreme precipitation indices of the ETCCDI were used to investigate their impact on water security, which was evaluated using unmet demand; demand coverage; reliability, resilience, and vulnerability; and aggregation index metrics. We found that prioritizing domestic and industrial water use is the optimal water security strategy, and unconditional allocation of instream flow can cause a significant water deficit for other water uses. However, prioritizing all water uses equally also proved effective under some conditions. Thus, our study highlights the importance of adaptive management and suggests that the optimal water allocation strategy lies in its flexibility in response to varying circumstances. [ABSTRACT FROM AUTHOR]

Reprogrammable shape morphing is ubiquitous in living beings and highly crucial for them to move in normal situations, even to survive under dangerous conditions. There is increasing interest in using asymmetric hydrogel structures to understand and mimic living beings’ shape morphing upon an external trigger in a controlled way. However, these asymmetric or heterogeneous configurations cannot be further modified once the polymer hydrogels are prepared. Therefore, it is a great challenge to achieve reprogrammable shape morphing using the existing hydrogels. Inspired by marine amoebae, which transform into several different morphologies according to the various external salt concentrations, a new strategy is developed for salting hydrogels to reconfigure their anisotropy toward reprogrammable shape morphing. Polyampholyte hydrogels with equal stoichiometric COO− and N+(CH3)3 groups were first swollen in HCl/NaCl solution. After being then transferred into water, they first swollen again by water uptake driven by the osmotic pressure, and then were spontaneously deswollen due to increase in internal pH and dialysis of ions leading to deprotonation of COOH to COO− and regeneration of COO−/N+(CH3)3 electrostatic attraction. This work provides a novel strategy to reconfigure anisotropy of hydrogel soft actuators and to open up an avenue for reprogrammable shape morphing. [ABSTRACT FROM AUTHOR]

Wireless power transfer (WPT) system in seawater exhibits distinct transmission characteristics from those in air due to the unique properties of seawater medium and the complexity of the seawater environment. In this paper, transmission characteristics of a 2-transmitter (2TX) and 1-receiver (1RX) WPT system in the frequency band of 350 ~ 550 kHz in seawater are investigated. When the transfer distance is at midrange, the maximum load voltage point of the system is shifted from 460 to 430 kHz compared to that in air, and the maximum transfer efficiency is 7 times of that in air, which is very different from the traditional view that the transfer efficiency in water is always worse than in air. The system maintains a stable output voltage when the receiving coil is at different offsets. To grasp the influence mechanism of seawater on wireless power transfer, two new parameters, complex self-inductance and complex mutual inductance, are introduced into the circuit model to explain the shift of the optimal frequency and the increase of transfer efficiency, and the model is verified through experiments. [ABSTRACT FROM AUTHOR]

The diel vertical variations of chlorophyll a (Chl-a) concentration are thought of primarily as an external manifestation of regulating phytoplankton's biomass, which is essential for dynamically estimating the biogeochemical cycle in inland waters. However, information on these variations is limited due to insufficient measurements. Undersampled observations lead to delayed responses in phytoplankton assessment, impacting accurate evaluations of carbon export and water quality in dynamic inland waters. Here, we report the first lidar-observed diel vertical variations of inland Chl-a concentration. Strong agreement with r2 of 0.83 and a root mean square relative difference (RMSRD) of 9.0% between the lidar-retrieved and in situ measured Chl-a concentration verified the feasibility of the Mie–fluorescence–Raman lidar (MFRL). An experiment conducted at a fixed observatory demonstrated the lidar-observed diel Chl-a concentration variations. The results showed that diel variations of Chl-a and the formation of subsurface phytoplankton layers were driven by light availability and variations in water temperature. Furthermore, the facilitation from solar radiation-regulated water temperature on the phytoplankton growth rate was revealed by the high correlation between water temperature and Chl-a concentration anomalies. Lidar technology is expected to provide new insights into continuous three-dimension observations and be of great importance in dynamic inland water ecosystems. [ABSTRACT FROM AUTHOR]

Environmentalists, ranchers, and Indigenous nations are increasingly coming together on environmental issues in what have been called "unlikely alliances," offering important insights into the role of collaboration and collective action in environmental governance. We examine two cases of unlikely alliances that formed in response to large rural-to-urban water transfer projects in the western United States, drawing on narrative analysis of interviews and focus groups with diverse participants. We highlight several key insights about unlikely alliances in action, finding that they 1) can take many different forms, often shifting over time; 2) require a delicate balance between alignment and autonomy, particularly when involving sovereign Indigenous nations; 3) can involve divergent understandings and expectations in regard to what it means to ally, with a notable distinction between issue-oriented and relationship-oriented approaches, and 4) are valued by participants even as they grapple with these challenges, particularly in the context of growing political polarization. [ABSTRACT FROM AUTHOR]

While the permeation mechanism of solute (e.g., ions and glucose) through biological membrane has been studied extensively, the mechanical role of water transport in intracellular phenomena has not received much attention. In the present study, to investigate the effect of water permeation on the intracellular pressure response, a novel permeation flux model through a biological membrane is developed by incorporating the coupling permeabilities (between water and ion fluxes) as the water-ion interaction in the ion channels. The proposed model is applied to a two-dimensional permeation problem of water and ions in a closed cell separated by a thin membrane. The permeation flux model reproduces the typical time response of intracellular pressure to action potentials with reasonable agreement with experimental results in the literature, indicating that the pressure response can be characterized by the following three parameters: water permeability, the mass ratio of water and ion, and the ratio of the permeation fluxes of water and ion. In particular, the permeation flux ratio plays an essential role in intracellular phenomena; depending on the value of the permeation flux ratio, the time lag between the action potential and the pressure response is 0.1 times smaller than that expected by the previous researchers, indicating that water transport associated with ions may trigger a pressure response. This study demonstrates the importance of water permeation in intracellular mechanical response through coupling of the fluid motion and electric fields. [ABSTRACT FROM AUTHOR]

Interbasin water transfer projects which are considered as a solution to the water crisis have different economic and environmental implications for regions. This study investigated the economic and welfare effects of agriculture water transfer to Qazvin Province in Iran using a water-embedded computable general equilibrium (CGE) model. The model was calibrated and solved numerically using a water-embededd social accounting matrix (WSAM). A scenario transferring 290 million m3 of water was simulated. The results indicate that this policy had a positive effect on the region's welfare and increased the gross production of the agricultural sector by 14.4%, which led to an increase in the production inputs and added value of the agricultural sector. With the increase in gross production, the exports of the agricultural sector increased and the need for imports decreased. With the change of variables in the agricultural sector, other economic sectors were affected directly and indirectly. The economic variables of Qazvin province—gross domestic product (GDP), capital formation, exports of agricultural products, industries, and service efficiency—had a positive response to the policy. [ABSTRACT FROM AUTHOR]

The analysis of the influence of human activities and climate change on groundwater is an important basis for formulating groundwater management policies. However, the relationship between climate change, human activities and groundwater system is complex, and the research on the response of groundwater to changing environment is in the initial stage. In this paper, the interactions between groundwater water cycle and climate change and human activities are analyzed, based on climate change data and hydrogeological information from the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). The MODFLOW model was used to develop a numerical model of shallow groundwater movement in Zhongmu County, Henan province, and to predict the response of groundwater levels to climate change and human activities in three cases from 2016 to 2050. The results show that under the current scenario, the groundwater level will decrease at an average annual rate of 4.24 cm/A from 2016 to 2050. Under the climate change scenario, the precipitation increased by an average of 5.01%, the annual evaporation increased by an average of 17.84% and the annual temperature increased by an average of 1.29 °C from 2016 to 2050 under the three emission cases of RCP2.6, RCP4.5 and RCP8.5, under the climate change–autonomous human activities scenario, when water conservation and South–North Water Transfer Project water supply are implemented simultaneously, the water table will decrease by an average of 5.58 CMA per year under the direct impact scenario and by an average of 4.44 CMA per year under the indirect impact scenario, the water table dropped by 3.21 cm/A. The changing environment will have an important effect on groundwater circulation, and appropriate measures must be taken to deal with the continuous decline of groundwater level. [ABSTRACT FROM AUTHOR]

Purpose: Megaprojects have large impact on the environment and stakeholders should take collective action to ensure that these projects are developed in a socially responsible manner. Hitherto, it is not known whether group and subjective norms and social identity could compel stakeholders to take socially responsible collective actions in megaprojects. The aim of this study is to design and test a model to boost stakeholders' intention to take socially responsible collective action in the context of mega water transfer projects in China. Design/methodology/approach: A quasi-experimental causal research design was adopted to establish cause–effect relationships among the dependent variable (we-intention) and independent variables (subjective norms, group norms, social identity and desire). This study adopts the belief–desire–intention model and social influence theory to empirically investigate how to boost the stakeholders' intention to participate in socially responsible collective action. An online questionnaire survey was conducted and data was collected from 365 respondents who were involved in mega water transfer projects in China. The partial least squares structural equation modeling technique was employed to analyze the data. Findings: The results from partial least squares analyses indicate that the presence of subjective norms, group norms and social identity (collectively known as social influence process) could increase stakeholders' intention to take socially responsible collective action. In addition, the desire to be socially responsible also boosts stakeholders' intention to take collective action. Desire partially mediates the relationship between social influence process and intention to take socially responsible collective action. Originality/value: This study adds to existing knowledge by discovering social influence process as an antecedent to taking socially responsible collective action in megaprojects. Strong group norms and subjective norms could propel stakeholders to be more socially responsible. The study also adds to knowledge by discovering that stakeholders' desire to fulfill social responsibility also leads them to take concrete actions. Implications and recommendations are provided on how to manipulate different types of social influence processes to facilitate stakeholders to adopt socially responsible collective action in the process of managing megaprojects. [ABSTRACT FROM AUTHOR]

Cotton, as a rich cellulose polysaccharide material in nature, has increasing applications. This work studies the transfer law of water in cotton fabric after liquid-ammonia treatment. The morphological and structural changes in cotton fabric, after liquid-ammonia treatment, are analyzed using scanning electron microscopy, Fourier-transform infrared spectroscopy, and X-ray diffraction. The relationships between the gaseous and liquid water-transfer performances and the fiber morphology and structure are studied. Cotton fiber swells after liquid-ammonia treatment, and its surface becomes relatively smooth with increasing treatment time. The fiber changes from a twisted bent shape to a cylindrical shape, with a slight increase in luster. The chemical structure of cotton fiber treated with liquid ammonia does not show significant changes; however, its crystallinity decreases. After liquid-ammonia treatment, the breaking strength of cotton fabric increases and the elongation at break decreases; the K/S value of the dyed fabric increases, while the L* value decreases accordingly. In addition, the breathability and moisture permeability increase. The wicking height first increases and then decreases, whereas the water retention gradually decreases. Using the entropy-weight–TOPSIS method, the water-transfer performance of cotton fabric treated with liquid ammonia at different times is comprehensively evaluated. The advantages and disadvantages of the treatment are ranked, to objectively and comprehensively analyze their rationality and theoretical significance. This work provides a new evaluation basis for the comprehensive analysis and evaluation of the moisture-transfer and moisture-comfort performance of cotton fabric. [ABSTRACT FROM AUTHOR]

As climate change intensifies, the need to conserve ecosystem services and our natural resources increases. Nature-based solutions projects that focus on sequestering carbon can also have significant impacts on the ecosystem services in the project area. Herein, we describe a method to quantify ecosystem services via the Integrated Valuation of Ecosystem Services and Tradeoffs (Version 3.14) model. We use those quantitative methods to show where carbon projects and other restoration projects could increase certain ecosystem services through best practices. Using the Edisto River Basin in South Carolina as a study site, we developed a spatial additionality model that shows where water retention, carbon, and sediment retention can be improved. InVEST modeling showed high levels of sediment export and water yield, with 0.12 tons/acre of sediment exported and 256.3 cm/acre of water yielded downstream on average. The model indicates that over 70,000 acres comprised of parcels greater than 20 contiguous acres could implement management to increase ecosystem service provisioning. This model output shows spatially where best management practices can be implemented to achieve positive outcomes and where carbon projects could be implemented to derive additional co-benefits. Furthermore, it can be used as a tool for measurement and verification as data is updated. [ABSTRACT FROM AUTHOR]

Developing an advanced strategy to decrease the charge recombination of BiVO4 is a vital requirement to boost charge transfer for photoelectrochemical water oxidation. Herein, a type II BiVO4/Bi2Mo2O9 heterojunction is successfully synthesized on fluorine‐doped tin oxide substrate by successive ionic layer adsorption and reaction method. Thanks to the Fermi‐level energy difference of 275 mV between BiVO4 and Bi2Mo2O9, an outward built‐in electric filed pointing from Bi2Mo2O9 to BiVO4 is induced, which accelerates the directional flowing of photogenerated electron and hole. Such a unique design structure fastens the electron migration from BiVO4 to Bi2Mo2O9, and the holes will transfer to the surface to participate in water oxidation. The longer lifetime (9.2 ns) by time‐resolved transient photoluminescence signifies that the Bi2Mo2O9 can boost interfacial carriers' anisotropic migration; the surface charge transfer rate of BiVO4/Bi2Mo2O9 is up to 387.6 s−1 (1.4 V vs reversible hydrogen electrode (RHE)). The BiVO4/Bi2Mo2O9 heterojunction exhibits a remarkable charge separation efficiency of 64% and outstanding photocurrent density of 0.9 mA cm−2 at 1.23 V versus RHE. [ABSTRACT FROM AUTHOR]

The Makassar Strait throughflow (MST) is the major component of the Indonesian Throughflow (ITF), transferring Pacific water into the Indian Ocean. In our previous study, we identified a new zonal pathway, a. k.a. the North Equatorial Subsurface Current (NESC), which carried equatorial water into the MST sub‐thermocline (>300 m) in the summer 2016 following the 2015/16 El Niño. We now show continued strong southward MST in the sub‐thermocline during the winter of 2016–2017, with salinity higher than that in the summer 2016, due to direct South Pacific water intrusion into the Sulawesi Sea. The origin of the intrusion is identified from the New Guinea Coastal Undercurrent (NGCUC) and from an anomalous westward flow along 3°N in the western equatorial Pacific. The identified interannual variability of the western Pacific Ocean circulation is particularly strong in the winter following super El Niño events. Plain Language Summary: The Indonesian Throughflow (ITF) transfers Pacific waters into the eastern Indian Ocean through the complex passages of the Maritime Continent, affecting the water properties and heat content in both oceans. The vertical structure of the ITF plays an important role in modulating the Indo‐Pacific Ocean heat content and climate. Understanding the Pacific water mass sources of the ITF and their variations is essential to understanding interocean heat and salt transports. The sub‐thermocline (>300 m) throughflow within the Indonesian Seas, has waters drawn from the relatively salty South Pacific thermocline. To date, the pathway of the South Pacific water into the ITF is not understood well. Here we present evidence showing a new pathway for high salinity South Pacific water flowing into the sub‐thermocline Makassar Strait directly after strong El Nino events, which may become more common in the future. This study helps to understand the importance of the South Pacific water in the variations of the Great Ocean Conveyer Belt and in biogeochemical processes with ecological impacts downstream of the ITF. Key Points: Strong anomalous southward flow with higher salinity in the winter of 2016–2017 was observed in the sub‐thermocline Makassar StraitThe high salinity is due to direct intrusion of South Pacific water from the western boundary current and an anomalous flow along 3 °NThe identified direct intrusion of South Pacific water into the Makassar Strait appears strong in the winter following a super El Niño [ABSTRACT FROM AUTHOR]

Catalytic transfer hydrogenation of levulinic acid (LA) to γ‐valerolactone (GVL) was attractive in biomass conversions since GVL is highly useful in different applications, such as polymer synthesis, fuel, and food. Various catalytic systems were reported for the reaction, yet harsh reaction conditions were generally required, which could restrict the scaling up of the reaction. Herein, we developed an effective and green bi‐solvent system of isopropanol/water for the catalytic transfer hydrogenation of LA to GVL over a ruthenium–phosphorous carbon (Ru‐PC) catalyst. It was found that the presence of water in the solvent system promoted the production of GVL from LA. The effect of isopropanol/water ratios and other reaction conditions were investigated, exhibiting that 93.8% yield of GVL was achieved using isopropanol/water ratio of 2.5:2.5 at 140 °C for 4 h and over Ru‐PC catalyst. Combining water and organic solvent not only reduced the usage of organic solvent but also created an effective bi‐solvent system for catalytic reactions. [ABSTRACT FROM AUTHOR]

The erosion and sedimentation of bank slopes are important factors affecting the safety of wharf operations. The essence of bank slope monitoring is to identify the water–soil interface. This paper proposes a model for soil-and-water interface identification and monitoring equipment buried on the bank slope of the wharf, based on the difference in thermodynamic heat transfer between water and soil media, and presents the results of multi-condition numerical simulation. The comparison between numerical simulation results and indoor experimental results shows that the overall patterns are consistent, with an error of less than 11.4%, which is lower than the deviation between theoretical calculation results and indoor experiments. Based on the accuracy of the numerical calculation results, the temperature rise and propagation characteristics of linear heat sources made of iron and PVC in eight types of cohesive soils and six types of non-cohesive soils were studied. The results indicate that there are significant differences in the temperature distribution of linear heat sources made of iron and PVC in both water and soil media. The monitoring equipment model based on the difference in heat transfer between water and soil can be applied in practical engineering. This provides a foundation for the design and application of subsequent monitoring equipment. [ABSTRACT FROM AUTHOR]

Optimizing both performance and stability under varying relative humidity (RH) conditions is crucial for proton exchange membrane fuel cells (PEMFCs). Therefore, effective management of mass transfer and water is an essential key factor. To further improve performance and stability, this paper reports a novel PEMFC design strategy that introduces carbon nanotube (CNT) sheets with titanium (Ti) deposited onto them as an additional functional layer using the sputtering method. The Ti‐CNT (as Ti‐deposited CNT is abbreviated to Ti‐CNT) sheets are inserted between the catalyst layer (CL) and the gas diffusion layer (GDL). This exhibit enhances performance across all testing conditions (25‐100% RH), which is attributed to their optimal pore structure and hydrophilic properties. It shows up to ≈94% higher power density and ≈60% improvement in charge transfer resistance compared to conventional. Moreover, stability tests conducted under a constant voltage demonstrated that this innovative design strategy significantly reduced degradation, thereby proving its superior stability. This novel design strategy of inserting Ti‐CNTs as a functional layer improves electrochemical performance and stability. [ABSTRACT FROM AUTHOR]

The Tibetan Plateau has exhibited a discernible trend towards increased precipitation over the past 50 years. However, previous research predominantly focused on thermal stability of permafrost without the consideration of water flux boundary conditions, and therefore ignored the dynamics of water migration and its impacts on the embankment stability. To bridge this gap, a novel water-heat transfer model incorporating rainfall and water migration was developed and subsequently validated using monitored data. Comparative analyses were then conducted across three distinct rainfall intensities to investigate the variations in the moisture and temperature of superficial soil. Results indicate rainfall events exert a notable cooling effect during warm seasons but have little influence on cooling during cold seasons. By increasing the latent heat of evaporation, sensible heat and reducing the soil heat flux, rainfall results in embankment cooling, and the cooling effect correlates positively with rainfall intensity. Disregarding the water flux boundary conditions will overestimate the embankment temperature and underestimate the variation of water content, especially at the superficial soil. Rainfall results in a decline in water vapor flux and an increase in liquid water flux, which facilitates rapid downward transport and accumulation of liquid water. Despite the increased convective heat transfer of liquid water, the decrease in heat conduction, latent heat of evaporation and convective heat transfer of water vapor in the embankment is more pronounced. Rainfall changes the stability of permafrost embankment mainly by adjusting the energy distribution, which delays temperature increases in the underlying permafrost. When predicting the stability of permafrost, it is recommended to incorporate the water flux boundary conditions. [ABSTRACT FROM AUTHOR]

Ozone-based advanced oxidation processes (AOPs) have emerged a promising avenue for water treatment, offering effective removal of micropollutants. Recent research underscores the potential of ozone microbubbles to enhance ozone mass transfer during water treatment, particularly when combined with pre-treatment steps. This study aimed to evaluate the efficacy of three different combined processes (chlorine/KMnO4/PAC pre-treatment followed by ozonation) in removing atrazine, a common micropollutant from natural source water. Results revealed that all combined processes achieved higher atrazine removal rates compared to individual pre-treatment or ozonation methods. Notably, the highest atrazine removal rates were observed under alkaline pH conditions, with treatment outcomes influenced by oxidant dose and pH levels. Among the combined processes, chlorine pre-treatment followed by ozonation emerged as the most effective approach, achieving a removal rate of 59.7% that exceeded the sum of individual treatments. However, this treatment efficacy was affected by water quality parameters, particularly the presence of organic matter and elevated ammonia nitrogen concentration (> 0.5 mg/L). This study highlights the potential for utilizing ozone micro/nanobubbles to enhance ozone mass transfer and offers valuable insights for optimizing the combined application of pre-treatment and ozonation strategies for efficient atrazine removal from natural water sources. [ABSTRACT FROM AUTHOR]

Traditional flow fields and gas diffusion layers (GDL) suffer from water flooding at the rib contact surface, resulting in mass transfer obstruction. Herein, an integrated component (i‐component) with tri‐part of the flow field, gas diffusion backing, and the microporous layer is prepared using the filter molding method to prevent flooding at the rib. The i‐component with micro‐tunnels is more compact than traditional fuel cells and has no distinct interface, significantly enhancing fuel cell performance, reducing mass transfer resistance, and improving water management. Remarkably, the mass transfer resistance of the i‐components is reduced by six times, accompanied by a 50% increase in power density (1.63 W cm−2) and a 146% surge in volume‐specific power (24 500 W L−1). Additionally, it exhibits excellent humidity tolerance in the relative humidity range of 30–100%. This method achieves large‐area i‐component (388 cm2) preparation in 0.5 h at 350 °C, which reduces time by dozens and energy consumption by over 100 times compared to the traditional method for preparing commercial GDL. The i‐component significantly enhances the mass transfer and water management capabilities of fuel cells. Hence, the i‐component provides new strategies for next‐generation fuel cells, water electrolysis, flow battery, carbon dioxide reduction, etc. [ABSTRACT FROM AUTHOR]

Commodity exports have played a crucial role in driving global economic growth, but they have also led to increased flow and consumption of natural resources worldwide. To measure and analyse the inter‐regional virtual water consumption and value‐added benefits driven by exports, as well as the unequal exchange between regions, we utilised the global supply chain database of Eora to construct a multi‐regional input–output (MRIO) model of virtual water consumption and value‐added benefits among 189 countries and regions from 1991 to 2016. We also proposed a virtual water consumption uneven index. The results highlight that relatively less developed regions accounted for 27% of the world's total export value added and 56% of virtual water exports. In contrast, relatively developed regions contributed 73% of the global export value added but only 44% of virtual water exports. The export of high‐value‐added products, such as financial services, was concentrated in the relatively developed regions, while water‐intensive products, like agriculture, forestry, and animal husbandry, were mainly exported by relatively less developed regions. Economically developed regions enjoyed a beneficiary position in terms of virtual water consumption, with each unit of export‐driven added value requiring only 4–100 kg of virtual water. Conversely, economically less developed regions consumed 140–1800 kg of virtual water per unit of export‐driven added value. The disparities in virtual water exchanges across different regions primarily stem from the differences between developed and less developed regions. Therefore, less developed regions and countries should focus on improving water efficiency in water‐consuming industries, adjusting the structure of export industries, and striving to reduce or reverse the disadvantageous position of resource consumption, such as virtual water, in global trade exports. [ABSTRACT FROM AUTHOR]

One of the main challenges most organic photodiodes (OPDs) facing is to overcome the traditional trade‐off between ultralow dark current and high responsivity (R) in existing research. Here, van der Waals multilayer OPD based on water transfer printing method, termed hybrid bulk‐heterojunction (BHJ)/planar‐heterojunction (PHJ) (B‐PHJ) framework, is constructed making certain the high‐quality interface and novel two‐phase energy band alignment between the active and barrier layer with noise suppression and photovoltaic complement simultaneously. The prepared OPD exhibits the combined advantages of ultralow dark current (0.2 nA cm−2 at −1 V) and high responsivity (0.49 A W−1 at 850 nm). As a result, these superimposed effects enable the device to feature a superior liner dynamic range (LDR) of 210 dB and a specific detectivity of 1014 Jones to address the conventional responsivity‐noise trade‐off. The results reveal that the balance dynamics of charge transfer and charge blocking in van der Waals hybrid two‐phase framework OPD, may inspire the development of next OPDs. Finally, its diverse practical application potential is demonstrated through long‐distance misaligned photoplethysmography (PPG) measurement. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Temperature gradient metamorphism in dry snow is driven by heat and water vapor transfer through snow, which includes conduction/diffusion processes in both air and ice phases, as well as sublimation and deposition at the ice–air interface. The latter processes are driven by the condensation coefficient α , a poorly constrained parameter in the literature. In the present paper, we use an upscaling method to derive heat and mass transfer models at the snow layer scale for values of α in the range 10 -10 to 1. A transition α value arises, of the order of 10 -4 , for typical snow microstructures (characteristic length ∼ 0.5 mm), such that the vapor transport is limited by sublimation–deposition below that value and by diffusion above it. Accordingly, different macroscopic models with specific domains of validity with respect to α values are derived. A comprehensive evaluation of the models is presented by comparison with three experimental datasets, as well as with pore-scale simulations using a simplified microstructure. The models reproduce the two main features of the experiments: the non-linear temperature profiles, with enhanced values in the center of the snow layer, and the mass transfer, with an abrupt basal mass loss. However, both features are underestimated overall by the models when compared to the experimental data. We investigate possible causes of these discrepancies and suggest potential improvements for the modeling of heat and mass transport in dry snow. [ABSTRACT FROM AUTHOR]

We present experimental results of a study on oxygen transfer rates in a water channel facility with varying turbulence inflow conditions set by an active grid. We compare the change in gas transfer rate with different turbulence characteristics of the flow set by four different water channel and grid configurations. It was found that the change in gas transfer rate correlates best with the turbulence intensity in the vertical direction. The most turbulent cases increased the gas transfer rate by 30% compared to the low turbulence reference case. Between the two most turbulent cases studied here, the streamwise turbulence and largest length scales in the flow change, while the gas transfer rate is relatively unchanged. In contrast, for the two less turbulent cases where the magnitude of the fluctuations normal to the free surface are also smaller, the gas transfer rate is significantly reduced. Since the air–water interface plays an important role in the gas transfer process, special attention is given to the free-surface deformations. Despite taking measures to minimise it, the active grid also leaves a direct imprint on the free surface, and the majority of the waves on the surface originate from the grid itself. Surface deformations were, however, ruled out as a main driver for the increase in gas transfer because the increase in surface area is < 0.25%, which is two orders of magnitude smaller than the measured change in the gas transfer rate. [ABSTRACT FROM AUTHOR]

This research investigates the origins of high-salinity water in the southern Bay of Bengal (SBHSW) in summer (June to August) and its interannual variabilities associated with El Niño-Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD). The two distinctive sources of the SBHSW, including the eastern Arabian Sea (AS) origin and the western equatorial Indian Ocean (EIO) origin mentioned in the previous studies are identified. The eastern AS origin has much higher salinity (35.5 PSU vs. 35.2 PSU), shallower isopycnal layers (1023.0–1023.5 kg m-3 vs. 1024.0–1024.5 kg m-3), and intrudes into the Bay of Bengal (BOB) approximately one month later compared to the western EIO origin, while accounting for 53% of the total salinity variability compared to 47% contribution from the western EIO origin. The interannual variabilities of SBHSW are closely linked with ENSO and IOD events, with contributions of approximately 47% and 41%, respectively. During El Niño decaying years, high-salinity water export from the western EIO origin into the southern bay (< 7°N) is enhanced due to the anomalous strong spring Equatorial Undercurrent (EUC) associated with El Niño; while in the north of 7°N, the SBHSW was freshened both by the increased rainfall and by the downwelling associate with the anomalous anticyclonic wind. Similar processes operate but in an opposite direction during La Niña decaying years. In contrast, IOD exerts its influence on the SBHSW primarily through modulating the strength of SMC. Positive (negative) IOD caused the anomalous freshening (salty) SBHSW by weakening (enhancing) SMC and consequently advecting less (more) saline water into the BOB. [ABSTRACT FROM AUTHOR]

The stability and performance of loess infrastructure in cold regions are often challenged by seasonal freezing–thawing action. The action of the foundation loess is a complex thermo-hydro-mechanical coupling process, and it is crucial to understand this process for the loess infrastructure in cold regions. A series of controlled tests were conducted to observe the changes in temperature, moisture, and frost heave variations within loess samples under freezing–thawing, and the influences of cycle period, freezing–thawing amplitude, and cycle number on the thermo-hydro-mechanical behavior of loess were investigated. The results reveal that freeze–thaw cycles significantly affect the heat transfer, water migration, and deformation of the loess. The temperatures of sample at different heights periodically vary under freezing–thawing. Water is absorbed to the samples, which undergoes a rapid water intake stage, a water drained stage, and a slow water intake stage under freezing–thawing, resulting in moisture redistribution in loess. Loess undergoes frost heave, thaw settlement, and consolidation processes during freezing–thawing, and a slight wetting collapse may occur after several freezing–thawing cycles. Within the same cycle, frost heave is the largest while consolidation deformation is the smallest. Frost heave and consolidation deformation reach their maximum values at the second cycle, whereas thaw settlement reaches its maximum value during the second or third cycle. Each stage deformation increases with an extended cycle period and almost decreases as the freezing–thawing amplitude increases. Freeze–thaw cycles can induce wetting collapse of loess, resulting in negative residual deformation. Furthermore, the thermo-hydro-mechanical coupling process and the deformation mechanism of loess have been elucidated. These insights contribute to a more comprehensive understanding of the failure mechanisms in loess engineering in cold regions. [ABSTRACT FROM AUTHOR]

In Iran, Behesht Abad Water Transfer from the headwaters of Karoon to the central plateau is one of the most critical inter-basin water transfer projects. This study aims to evaluate the impacts of the Water Transfer (WT) on the water level and flow of Farsan Aquifer in the origin basin. To achieve this goal, WEAP-GMS was used. Some defined scenarios include maximum water transfer from the origin to the destination basin in three modes of normal hydrologic, drought, and increasing environmental demand of the river. The maximum transferable water in a normal year is 450 and deceases to 160 MCM in a drought year. Also, the groundwater level before and after WT, the flow direction, the dry aquifer surface, and the dry wells were calculated. The results demonstrate that water transfer in the long term will cause a drop in the aquifer volume and level of the origin basin. Almost 34% of the aquifer surface and 138 wells will be thoroughly dried. Based on the results, inter-basin water transfer plans may solve the water shortage of the destination basin (recipients) over the short-term, but in long periods have adverse impacts on the environmental sustainability of the origin basin (donor). [ABSTRACT FROM AUTHOR]

Reservoir sediment severely impacts water supply in water-scarce regions, making reservoir dredging an urgent global issue. The investment required for deep-water dredging far exceeds that for dry land dredging. Therefore, against the backdrop of the national water network construction, this study focuses on a typical inter-basin water transfer project in Northern China. To increase the proportion of dry land dredging volume and save costs, this study uses compensation reservoirs to replace the emptied reservoir in undertaking water supply tasks as a constraint. Single-objective optimization models for single reservoirs and multi-objective optimization models for reservoir groups are established, using game theory comprehensive subjective and objective weighting methods to select the optimal solution. The following conclusions are drawn from comparing the water supply effects under various emptying sequences: the optimal sequence for emptying reservoirs should be determined through precise quantitative analysis; as the dredging is completed, the water supply tends to stabilize; the satisfaction with the water supply and the variance of the water shortage rate are primarily related to reservoirs with a large inflow and storage capacity; dredging occurs according to the descending order of the storage capacity of reservoirs; and the startup proportion of pump stations shows an increasing trend. [ABSTRACT FROM AUTHOR]

In India, air conditioning is essential in the truck driver's cabin during the summer. An air conditioning system powered by the vehicle's engine adds to the engine's workload, resulting in higher fuel demand and more emissions. An adsorption chiller that runs on engine exhaust is designed here to lower the interior temperature of a truck cabin to address the above-mentioned issue. Here, an adsorption air conditioner system's effectiveness is forecast using a lumped analytical technique. During the adsorption process, heat from the adsorber bed is absorbed by cold water and released into the radiator. The desorber bed has been heated using hot water as a heat transfer medium from the engine exhaust heat. The analysis was carried out using the adsorption kinetic equation at adsorption equilibrium. The influence of inlet water flow rate, temperature and switching time (adsorber process to desorber process and vice versa) on adsorption chiller performance has been studied here. According to simulation results, the proposed adsorption chiller can be used to keep the driver cabin cool during summer for operational conditions adopted during the simulation. The adsorption air conditioner's highest coefficient of performance (COP), as determined by this investigation, was found to be 0.214. [ABSTRACT FROM AUTHOR]

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In the latest years, the concentration levels of certain metals and metalloids in the sediments of the Galician Rías have shown an increasing trend (e.g., As, Zn, Cu, Pb, Hg). These areas are also characterized by their richness in nutrients and their great aquaculture or mariculture activity, with the presence of more than 3500 mussel rafts in the Rías Baixas. The inner areas of the Galician Rías are subjected to activities that resuspend the sediment such as high levels of maritime traffic and dredging or cleaning operations. It is likely that a transfer of these elements to the water column happens during the resuspension of sediments caused by natural events or anthropogenic activities. In this study, selected samples of surface sediments of the Ría de Pontevedra (NW Spain) were subjected to a procedure of aerobic oxidation to determine the concentration of some elements (Fe, Mn, Cu, Cr, Pb, Hg, and Zn) released from the sediment to the aqueous phase. The experiment was carried out within 5 days. Measurements of pH and total concentration were taken both in water and sediment samples. Furthermore, speciation of trace elements was carried out in the sediment samples. Trace element concentrations were lower in the sediments during aerobic oxidation, being released to the aqueous phase. From an environmental point of view, Cu was the only trace element released in quantities that may be toxic for the organisms in the area. This problem of sediment oxidation related to dredging activities or natural storm conditions should be considered in environmental impact studies and transferred to stakeholders. [ABSTRACT FROM AUTHOR]

Inter-basin water transfer projects, such as the Yellow River to Qingdao Water Diversion Project (YQWD), are essential for addressing water scarcity, but impact local aquatic ecosystems. This study investigates the seasonal characteristics of eukaryotic microbial communities in the Jihongtan Reservoir, the main water-receiving body of YQWD, over a one-year period using 18S rDNA amplicon sequencing. The results showed that the eukaryotic microbial diversity did not exhibit significant seasonal variation (p > 0.05), but there was a notable variance in the community structure (p < 0.05). Arthropoda and Paracyclopina, representing the most dominant phylum and the most dominant genus, respectively, both exhibited the lowest abundance during the winter. The Chlorophyta, as the second-dominant phylum, demonstrates its higher abundance in the spring and winter. The Mantel test and PLS-PM (Partial Least Squares Path Modeling) revealed that water temperature (WT), dissolved oxygen (DO), and pH influenced the seasonal dynamic of eukaryotic microbial communities significantly, of which WT was the primary driving factor. In addition to environmental factors, water diversion is likely to be an important influencing factor. The results of the co-occurrence network and robustness suggested that the spring network is the most complex and exhibits the highest stability. Moreover, keystone taxa within networks have been identified, revealing that these key groups encompass both abundant and rare species, with specificity to different seasons. These insights are vital for understanding the seasonal variation of microbial communities in the Jihongtan Reservoir during ongoing water diversions. [ABSTRACT FROM AUTHOR]

Shelf water is influenced by atmospheric forcing, river outflows, and the open ocean. Studying its variability is crucial for understanding anthropogenic impacts on coastal oceans and their transport to the open ocean. In the Middle Atlantic Bight (MAB), the interaction of the Gulf Stream with shelf/slope circulation leads to some of the complex exchanges between the shelf and open ocean along the U.S. East Coast. This study employs a Lagrangian particle tracking approach, grounded in a high‐resolution, data‐assimilative ocean reanalysis, to examine the export pathways of surface shelf water in the MAB. We analyzed over 700 daily images of simulated particle distributions using image clustering techniques. This revealed three distinct export patterns: abrupt entrainment to the Gulf Stream, gradual entrainment, and southern transport. Each pattern was observed roughly equally during the study period from January 2017 to December 2018. The observed export patterns are closely linked to the coastal circulation dynamics near Cape Hatteras. Understanding the timing and duration of these patterns is vital for assessing water quality and predicting the settlement of species that spawn in the region. Our study further underscores the influence of tropical cyclones, including Hurricanes Jose, Maria, and Chris, on these export patterns. These extreme weather events lead to significant shifts in coastal circulation near Cape Hatteras. Plain Language Summary: This study focuses on the movement of ocean water in the Middle Atlantic Bight (MAB), a region along the U.S. east coast. The movement of this coastal water, or "shelf water," is affected by the weather, rivers, and the ocean. A Lagrangian particle tracking method was used to track the movement of water by simulating how particles move in the coastal ocean. Over 700 daily images of particle tracking simulations were obtained. Shelf water moves out of the MAB by three main pathways: abrupt entrainment, gradual entrainment, and southern transport. Each of these pathways happened about equally over 2 years (2017–2018). Understanding these water movements is key for knowing how long water stays in an area, which is important for water quality and for the life cycle of marine species that breed there. The study also highlights how tropical cyclones (like Hurricanes Jose, Maria, and Chris) can dramatically change these water movement patterns, especially near Cape Hatteras. Key Points: Three Middle Atlantic Bight shelf water export patterns linked to specific wind conditions are identifiedLagrangian flow patterns of the MAB Shelf Water were notably impacted by 2017 and 2018 Atlantic Hurricane SeasonsSea Surface Velocity maps and Progressive Vector Diagrams reveal varied estuarine water pathways from Chesapeake and Delaware Bays [ABSTRACT FROM AUTHOR]

This paper investigates the impregnation of Japanese cedar (Cryptomeria japonica D. Don) with water using ultrasound irradiation, followed by immersion in water containing bulk nanobubbles (NBs). Cavitation bubbles generated during ultrasound irradiation mechanically remove extractives from the wood surface, enhancing the mass transfer of water into the wood. Water containing bulk NBs has a lower surface tension compared to pure water, enabling superior permeability into narrow spaces. However, the application of water containing NBs for wood impregnation post-sonication remains underexplored. In this study, wood was subjected to ultrasound irradiation at 38 kHz, followed by immersion in water containing bulk NBs, to determine the optimal sonication time and NB concentration for efficient impregnation. The results indicate that water uptake by the wood initially increases and then decreases with increasing NB concentration and sonication time. Optimal sonication time and NB concentration resulted in highly efficient impregnation. [ABSTRACT FROM AUTHOR]

A large number of force fields have been proposed for describing the behavior of liquid water within classical atomistic simulations, particularly molecular dynamics. In the past two decades, models that incorporate molecular polarizability and even charge transfer have become more prevalent, in attempts to develop more accurate descriptions. These are frequently parameterized to reproduce the measured thermodynamics, phase behavior, and structure of water. On the other hand, the dynamics of water is rarely considered in the construction of these models, despite its importance in their ultimate applications. In this paper, we explore the structure and dynamics of polarizable and charge-transfer water models, with a focus on timescales that directly or indirectly relate to hydrogen bond (H-bond) making and breaking. Moreover, we use the recently developed fluctuation theory for dynamics to determine the temperature dependence of these properties to shed light on the driving forces. This approach provides key insight into the timescale activation energies through a rigorous decomposition into contributions from the different interactions, including polarization and charge transfer. The results show that charge transfer effects have a negligible effect on the activation energies. Furthermore, the same tension between electrostatic and van der Waals interactions that is found in fixed-charge water models also governs the behavior of polarizable models. The models are found to involve significant energy–entropy compensation, pointing to the importance of developing water models that accurately describe the temperature dependence of water structure and dynamics. [ABSTRACT FROM AUTHOR]

Due to the influence of geometric factors, the temperature and humidity profile of lidar's near-field signal was warped when sensing the air environment. In order to perform geometric factor correction on near-field signals, this article proposes different correction solutions for the Mie and Raman scattering channels. Here, the Mie scattering channel used the Raman method to invert the aerosol backscatter coefficient and correct the extinction coefficient in the transition zone. The geometric factor was the ratio of the measured signal to the forward-computed vibration Raman scattering signal. The aerosol optical characteristics were reversed using the corrected echo signal, and the US standard atmospheric model was added to the missing signal in the blind zone, reflecting the aerosol evolution process. The stability and dependability of the proposed algorithm were validated by the consistency between the visibility provided by the Environmental Protection Agency and the visibility acquired via lidar retrieval data. The near-field humidity data were supplemented by the interpolation method in the Raman scattering channel to reflect the water vapor transfer process in the temporal dimension. The measured transmittance curve of the filter, the theoretical normalized spectrum, and the sounding data were used to compute the delay geometric factor. The temperature was retrieved and the near-field signal distortion issue was resolved by applying the corrected quotient of the temperature channel. The proposed algorithm exhibited robustness and universality, enhancing the system's detection accuracy compared to the temperature and humidity data constantly recorded by the probes in the meteorological gradient tower, which have a high correlation with the lidar observation data. The comparison between lidar data and instrument monitoring data showed that the proposed algorithm could effectively correct distorted echo signals in the transition zone, which was of great value for promoting the application of lidar in the meteorological monitoring of the urban canopy layer. [ABSTRACT FROM AUTHOR]

South-to-North Water Diversion Project, a globally renowned engineering feat, aims to address water supply issues. The sediments within reservoirs play a pivotal role in natural ecosystems, not only as habitats for diverse biota but also as repositories of heavy metals, organic matter, and other contaminants. These sediments serve as a critical interface between sediment and water bodies. This comprehensive analysis focused on the spatial patterns of nutrients, organic matter, and heavy metals in the surface layer and profiles of reservoirs, exploring their interconnectedness. Leveraging the integrated pollution index, organic pollution index, potential ecological risk index, and geo-accumulation index, an ecological risk assessment was performed. The key findings are as follows: (i) Along the Middle Route of the South-to-North Diversion Project, the nutrient and organic matter contents in sediments tends to rise with distance from the Danjiangkou Reservoir, with the TN and TC contents increasing by 2.35- and 3.05-fold, respectively. (ii) As the sediment depth increases, the carbon, nitrogen, phosphorus, and organic matter contents exhibit varying degrees of decline, with average decreases of 62.38%, 67.47%, 17.56%, and 41.83% for TN, TC, TP, and OM, respectively. (iii) Among the eight heavy metals, only manganese (Mn) and zinc (Zn) in the Yahekou Reservoir showed moderate pollution levels, according to the geo-accumulation index. The Mn content within the surface sediments of the six reservoirs ranges from 550 to 1837 mg/kg (average, 1019.5 ± 548.3 mg/kg), whereas the Zn content ranges from 89 to 360 mg/kg (average, 156.5 ± 101.6 mg/kg). (vi) Total phosphorus (TP) and total nitrogen (TN) emerged as the primary pollutants in surface sediments. Comprehensive nitrogen and phosphorus pollution assessment revealed that the surface sediment of Danjiangkou Reservoir is mildly polluted, while Baiguishan and Jiangang Reservoirs are moderately polluted, and the rest are heavily contaminated. For the Yahekou and Chaohe Reservoirs, the average pollutant content indicates moderate pollution, while the remaining reservoirs show mild pollution levels. Highlights: Characteristics of nutrients in the profile of sediments were investigated. Complex relationship between organic matter and heavy metal was revealed. Water quality of part reservoirs has ecological risk by the multiple methods. [ABSTRACT FROM AUTHOR]

Objectives: Land subsidence caused by long-term over-exploitation of groundwater is one of major problems in Beijing. Since the opening of the South-to-North Water Transfer Project, the problem of water shortage in Beijing has been greatly alleviated, and the pressure of land subsidence has been reduced to a certain extent. Methods: In order to analyze the development of land subsidence after the start of the South-to-North Water Transfer in Beijing, ascending and descending time-series interferometric synthetic aperture radar (InSAR) technique is used to monitor land subsidence in Beijing. First, the mean deformation velocity and cumulative deformation in line of sight in Beijing from January 2015 to December 2020 is obtained by the small baseline subset InSAR. Second, the robust least square fitting method is used to fuse the deformation results of the lifting rail, after that the global positioning system monitoring data are compared with the fusion results of lifting rail. Finally, the variation trend between the deformation results obtained by the robust least quadratic fitting and groundwater data is analyzed. Results: The deformation results show that the center of Beijing is basically stable and the deformation distribution is not uniform. The maximum ascending annual deformation velocity and the maximum ascending cumulative deformation amount reach −134 mm/a and −697 mm respectively. The maximum descending annual deformation velocity and the maximum descending cumulative deformation amount reach −135 mm/a and −734 mm respectively. And the fusion results obtained by the least square fitting method has reliability and accuracy. Conclusions: The subsidence rate in Beijing shows a decreasing trend with the gradual increase of groundwater level. In general, the middle route of South-to-North Water Transfer Project has alleviated the expansion trend of land subsidence in Beijing to a certain extent. [ABSTRACT FROM AUTHOR]

Inter-basin water transfers are implemented to counter the uneven geographical distribution of natural water sources. This paper's novelty consists of providing a system-dynamics framework to evaluate inter-basin water transfers based on integrated water governance. The Big Karun Basin, Iran, has long been of interest to water managers due to its discharge potential. It houses several water-transfer projects that are under operation or under study for possible future implementation. This study implements system dynamics modeling (SDM) in the Big Karun Basin considering existing inter-basin water transfers. This study's results estimate an average annual 8 to 10 billion cubic meters of water are transferred from the Karun River to the Persian Gulf. Part of this flow can be used to meet some of the water demands in Iran's central and eastern basins subject to social and environmental assessment of impacts. SDM modeling was also implemented accounting for the existing water transfers plus the under-study water transfers. This study's results indicate the firm energy from hydropower produced by the Big Karun Basin system would decrease by 28% relative to existing water transfer conditions. This issue raises concerns given the Big Karun Basin contribution to electricity production Iran. The water supply to several sectors would be marginally impacted by future water tranfers, yet water quality would be compromised in some instances. Therefore, the Big Karun Basin water system was simulated considering inter-basin water governance based on hedging rules for the under-study water transfers. Results indicate the minimum drinking and industrial demands could be met. In addition, the firm energy from hydropower produced by the Big Karun Basin system would decline by 12% relative to existing water-transfer conditions and the vulnerability of the water system would decline in terms of required quality for downstream demands and water users in comparison with the full-transfer water condition. [ABSTRACT FROM AUTHOR]

The tubular pump is a typical water transfer apparatus designed for extremely low heads and large flow rates. It serves as the core equipment in pumping stations situated at lakes, rivers, and canals. An adverse effect on the ecological environment stems from fish injury and mortality primarily caused by blade strikes. The present work combines computational fluid dynamics and the discrete element method to simulate the dynamics of fish passing through a simplified blade, allowing us to establish a safe margin of the strike force to further assess fish damage in a more complex tubular pump system. The results indicated that strikes on fish alter their motion state in terms of direction and magnitude, inducing chaotic movements that heighten the risk of subsequent strikes with downstream components. Fish tend to align their velocities with the surrounding fluid due to flow-induced drag after multiple contacts with solid structures. The knife-shaped leading edge, and particularly the blade tip side, emerged as the primary factor in creating strike damage, and the adoption of a slanted and blunt leading edge can effectively reduce fish damage. In addition, decreasing the shaft speed, increasing the flow rate, and restricting the fish size were identified as measures conducive to fish survival in running pumps. The study further suggested that using fewer but larger pumps operating at lower shaft speeds would contribute to better fish friendliness, which can also ensure a sufficient delivery head and mass flow rate. [ABSTRACT FROM AUTHOR]

Taitema Lake, situated at the terminus of the Tarim River Basin in Northwest China, represents a crucial ecological resource impacted by climate variability and anthropogenic interventions. In this study, we investigate the dynamic changes in Taitema Lake's area and water quality resulting from the implementation of an ecological water transfer project in 2000. Leveraging Landsat remote sensing data and comprehensive water quality monitoring, we analyzed the relationship between lake area variations and shifts in water quality parameters. Notably, our findings reveal a significant increase in Taitema Lake's area from 9.4 km2 in 2000 to 320 km2 in 2013. Concurrently, water quality indicators exhibited marked fluctuations, with total salt content ranging from 45,323.6 mg/L in 2000 to 970.4 mg/L in 2010 before increasing to 14,586.3 mg/L by 2014. Furthermore, a linear regression analysis highlights the moderate positive correlation between lake area and mineralization (R2 = 0.506) and sodium levels (R2 = 0.4907). Additionally, chloride (R2 = 0.5681) and sulfate (R2 = 0.6213) concentrations demonstrated a strong negative correlation with the lake area, indicative of a dilution effect. Furthermore, a comparison of water quality indicators between the years of minimum (2008) and maximum (2013) lake area underscores improvements in pH, chemical oxygen demand, and anionic surfactant concentrations as the lake area increased. Our study provides valuable insights into the effectiveness of ecological water management strategies in restoring and maintaining the ecological health of Taitema Lake, thereby informing evidence-based decision-making for the sustainable management of freshwater resources in arid environments. [ABSTRACT FROM AUTHOR]