Water Accumulation Research Articles

Biomimetic Adaptive Building Façade Modeling for Sustainable Urban Freshwater Ecosystems: Integration of Nature's Water-Harvesting Strategy into Sun-Breakers.

Urban freshwater ecosystems have many critical functions, such as providing water to all living things and supporting biodiversity. Factors such as water pollution, increased water consumption, habitat loss, climate change, and drought threaten the health of urban freshwater ecosystems. Looking for solutions to these challenges, this article aims to recycle water and return it to its life cycle using a climate-sensitive water collection strategy. The model focuses on the biomimetic method as a basic strategy. In this regard, the concept of water-harvesting has been examined in detail by conducting a deep literature review, including architecture and engineering disciplines. With all these data obtained, a synthesis/integration study was carried out by developing a model proposal based on adaptive building façade elements to solve the water problems experienced in cities. The model proposal, which is directly related to the titles of "Clean Water and Sanitation (SDG 6)" and "Sustainable Cities and Communities (SDG 11)", which are among the Sustainable Development Goals (SDGs), aims to provide different perspectives on the disciplines with its superficial and functional features. In this context, it is anticipated that the article will become an indispensable resource for other researchers working on the subject.

Leaf Vein-Inspired Superhydrophilic Microchannels for Sustainable Fog Collection.

Fog collection is a promising solution for mitigating the urgent water shortage around the world. Despite the delicate design of various bionic fog harvesting surfaces with prowess to enable fast fog capture and programmed water transport, achieving sustainable and efficient fog collection by regulating the macroscale surface refreshment efficacy remains rarely concerned yet is effective. Here, we proposed a bioinspired structural design to achieve significant improvement on the surface refreshment efficacy to 46.47%, nearly 5 times larger than that of conventional design. Specifically, we constructed superhydrophilic vein-like microchannels on a superhydrophobic brass surface by using laser texture technology and hydrothermal treatment. Our microchannel design acts as a "highway" for synergically transporting and converging the collected fog droplets, as well as rapidly refreshing large surface area for the subsequent fog collection, reminiscent of the leaf veins responsible for the persistent mass transport between plant tissues. The practical implementation also convinced our design of a maximum water collection efficiency of up to 506.67 mg cm-2 h-1 and a long-term performance stability within a 10 h test. Our design is generic to most of the fog harvesting materials, showing great application potential for efficient atmospheric fog collection.

Degradation of Emamectin Benzoate in the Aquaculture Pond Environment under Tropical Climatic Condition

Emamectin Benzoate (EMB), is an anti-parasitic drug, commonly used in aquaculture for prevention and control of parasitic infestations. The drug enters the environment through uneaten feed and faeces, ultimately accumulating in aquaculture pond sediment. Present study reports the influence of abiotic factors like, sunlight exposure (2,454 to 117,500 lux), pH, salinity and soil texture on the degradation of EMB in aquaculture pond water and sediment as per Organization for Economic Cooperation and Development (OECD). Results showed that the degradation of EMB in both water and sediment followed first-order kinetics, resulting in half-life of 5.6 days in water and 12.4 days in sediment when exposed to natural sunlight. Higher degradation of EMB was observed under alkaline conditions (pH 8.5) and at lower salinity (0.5ppt). EMB degradation is accelerated in loamy sand soil when exposed to sunlight. Results of the study suggest that in countries like India, where ample sunlight exposure is prevalent throughout the year, EMB degradation in aquaculture pond environment occurs at a rapid pace reducing the risk of accumulation in water or sediment.

On the Selection of the Current Collector for Water Processed Activated Carbon Electrodes for Their Application in Electrochemical Capacitors

AbstractElectrode manufacturing for electrochemical energy storage technologies often relies on hazardous fluorine‐containing compounds and toxic organic solvents. To align with sustainability goals and reduce costs, there is a pressing need for water‐processable alternatives. These alternatives can halve electrode processing costs and ease regulatory burdens. While progress has been made with water‐processed graphite electrodes using eco‐friendly binders, challenges persist for high‐mass loading activated carbon (AC) electrodes. This study investigates the impact of modified aluminium current collectors on water‐processed AC electrodes, focusing on compatibility, processability, and electrochemical performance. Various aluminium foils, including etched and carbon‐coated types, were evaluated. The results show that modifications at the interface significantly improve the wetting properties and mechanical stability. Electrochemical tests revealed that carbon‐coated aluminium provided the lowest internal resistance and highest rate capability due to intimate contact between the electrode components. In contrast, etched aluminium foil exhibited higher contact resistance and poorer performance. Ageing studies demonstrated that carbon‐coated foils maintained better electrochemical performance over time, as the carbon layer reduced degradation reactions and contact resistance. These findings suggest that uniformly carbon‐coated aluminium current collectors are the optimal choice for high‐power electrochemical capacitors, balancing performance, sustainability, and cost‐efficiency.

Comparative Analysis of Concentrations of Heavy Metals in Surface Water of Nafada, Ashaka and Almakashi Corridors of River Gongola, Nigeria

A study on comparative analysis of heavy metals concentrations in surface water was carried out in three selected stations: Nafada, Ashaka and Almakashi along the corridors of River Gongola in Gombe state for a period of eighteen months. The water samples were collected in triplicate from the sampling stations. Water samples were collected using sampling bottles of 250ml dipped below the water surface for water collection. Zinc, lead, copper, cadmium and manganese were determined using Atomic Absorption Spectrophotometer. The result elucidates that most of the heavy metals were found to be within the recommended ranges as compared to standard limits. The result of concentrations of heavy metals in the surface water elucidates that there was a significant difference (P>0.05) among the months with respect to zinc and there was no significant difference in the concentration of lead (P<0.05). The concentrations follow the order (Zn >Cd>Cu>Mn>Pb). The higher concentration of heavy metals was found in Ashaka corridors with Zinc concentration ranging between 0.99±0.01 and 0.33±0.01, Cadmium 0.88±0.02 and 0.03±0.00, Cupper 0.58±0.02 and 0.14±0.02, Manganese 0.87±0.56 and 0.17±0.01, Lead 0.28±0.36 and 0.01±0.01. The wastewater from the cement effluent factory in Ashaka might have impacted negatively on the water chemistry by elevating the levels of some heavy metals. Therefore, more intensive treatment of the factory effluents before discharging into the River Gongola is recommended.

Engineering of Hierarchical Porous Composite Film (ZIF-8@PVDF/PMMA) with Superhydrophobicity for Highly Efficient Water Harvesting.

Atmospheric water harvesting has attracted much attention because of its potential to escalate the global freshwater shortage. However, the water collection efficiency is hindered by the trade-off between fast droplet nucleating and rapid droplet dripping due to the opposite requirements in the chemistry and the morphology of surfaces. Herein, the hierarchical porous composite film (ZIF-8@PVDF/PMMA, HPCF) with superhydrophobicity is designed for highly efficient and stable water harvesting. It indicates that the HPCF film has a large water contact angle (WCA) of 155.50° and ultralow sliding angle (SA) of 2°, exhibiting the self-cleaning function. Significantly, it is demonstrated that the water collection efficiency of HPCF can achieve 1.13 g·cm-2·h-1, which is much higher than the value of the blank sample, as well as most of the reported values. It is attributed to the hierarchical porous structure with the ZIF-8 crystals enhancing the surface roughness and endowing the film with the hydrophilic/superhydrophobic regions. This design promotes an optimal balance between droplet nucleation and shedding, significantly enhancing the water harvesting efficiency. Consequently, this work introduces an effective approach for water collection materials suitable for fog/mist conditions and provides an effective solution for the foggy area with water scarcity, demonstrating significance for advancing research aimed at mitigating the worldwide water shortage.

The Implementation of IoT Sensors in Fog Collector Towers and Flowmeters for the Control of Water Collection and Distribution

This study describes the implementation of Internet of Things (IoT) sensors in flow meters installed in drinking water systems and in fog catchers built in low-income, high-altitude communities in the Andes region of Ecuador, taking studies at the University de las Fuerzas Armadas ESPE as our reference. The influence and management of these intelligent sensors are analyzed, as well as a basic review of the materials and methods used in their implementation. The importance of validating the accuracy and reliability of IoT sensors compared to professional devices is highlighted, especially in mountain areas with difficult access. Additionally, the cost–benefit of using IoT sensors in fog catchers and drinking water distribution networks is mentioned, which depends on several factors such as the scale of the project, the objectives to be achieved concerning monitoring, and the available resources. Finally, it is highlighted that using Internet of Things (IoT) sensors in construction and water collection systems has proven beneficial in detecting possible effects on its operation and determining consumption and supply flows for a given population.

Organic Capillary Barriers for Soil Water Accumulation in Agriculture: Design, Efficiency and Stability

Acute shortage of water resources and high unproductive water losses are the key problems of irrigated agriculture in arid regions. One of the possible solutions is to optimize soil water retention using natural and synthetic polymer water absorbers. Our approach uses the HYDRUS-1D design to optimize the placement of organic water absorbents such as peat and composite hydrogels in the soil profile in the form of water-storing capillary barriers. Field testing of the approach used a water balance greenhouse experiment with the cultivation of butternut squash (butternut squash (Cucurbita moschata (Duchesne, 1786)) under sprinkler irrigation with measurement of the soil moisture profile and unproductive water losses in the form of lysimetric water outflow. In addition, the biodegradation rate of organic water absorbents was studied at the soil surface and at a depth of 20 cm. Organic capillary barriers reduced unproductive water losses by 40–70%, retaining water in the topsoil and increasing evapotranspiration by 70–130% with a corresponding increase in plant biomass and fruit yield. The deepening of organic soil modifiers to the calculated depth not only allowed capillary barriers to form, but also prevented their biodegradation. The best results in soil water retention, plant growth and yield according to the “dose-effect” criterion were obtained for a composite superabsorbent with peat filling of an acrylic polymer matrix. The study showed good compliance between the HYDRUS design and the actual efficiency of capillary barriers as an innovative technology for irrigated agriculture using natural and synthetic water absorbents.

Comprehensive Analysis of Agricultural Practices in Adapting Soil, Water and Pest Management to Climate Change in Sub-Saharan Africa

Agriculture constitutes the primary economic sector in Sub-Saharan African (SSA) countries, engaging over 70% of the population, predominantly vulnerable rural communities. For decades, agriculture in SSA has grappled with climatic constraints, intensifying the vulnerability of impoverished communities. In response, communities have developed indigenous practices to adapt to these climatic hazards, warranting greater recognition for potential optimization. This review identifies agricultural practices related to climate change adaptation, specifically focusing on soil management, water, and pests. The operational mechanisms of the most widely utilized practices were scrutinized through a thorough analysis. The study concludes by identifying nine practice categories. Results indicate that water collection practices and the use of organic fertilizers are the most prevalent in soil and water management. Additionally, agricultural and biological control practices dominate pest management. The comprehensive analysis underscores that the most frequently cited practices may not always be the easiest to implement. Nevertheless, these practices are agro-ecologically sustainable, contributing to soil health restoration, efficient water management, and pest control in Sub-Saharan African countries. The findings suggest a need for a research program that concentrates on the simultaneous application of these practices, enabling their optimization for more sustainable agriculture, particularly in the context of climate change adaptation and soil fertility restoration in Sub-Saharan Africa.

Effect of Water Immersion on the Reoxidation Capacity of Coal with Different Secondary Oxidation Degrees

ABSTRACT Water accumulation and secondary oxidation of residual coal are commonly encountered in goaf, which can endanger the safety of coal mines. Both factors can affect the oxidation capacity of coal. Hence, it is essential to investigate the reoxidation capacity of residual coal with secondary oxidation in goaf after water immersion. This helps reveal the influence of different degrees of water immersion on coal samples with varying degrees of secondary oxidation. In this study, a programmed temperature system was used to examine the re-burning capacity of bituminous coal under the combined effects of secondary oxidation and water immersion. An electron spin resonance spectrometer was employed to examine the alteration in free radicals present for analyzing the evolution of microscopic groups of coal. According to the research results, under the same soaking conditions, an increase in secondary oxidation temperature leads to a decrease in the reoxidation capacity of coal. During re-oxidation, the immersion in water accelerates the process in bituminous coal with a secondary oxidation temperature of 120°C, while it has a certain inhibitory effect on coal samples with a secondary oxidation temperature of 180°C. This research lays a theoretical foundation for comprehending the re-oxidation of coal under complex conditions.

Deformation-Adapted Spatial Domain Filtering Algorithm for UAV Mining Subsidence Monitoring

Underground coal mining induces surface subsidence, leading to disasters such as damage to buildings and infrastructure, landslides, and surface water accumulation. Preventing and controlling disasters in subsidence areas and reutilizing land depend on understanding subsidence regularity and obtaining surface subsidence monitoring data. These data are crucial for the reutilization of regional land resources and disaster prevention and control. Subsidence hazards are also a key constraint to mine development. Recently, with the rapid advancement of UAV technology, the use of UAV photogrammetry for surface subsidence monitoring has become a significant trend in this field. The periodic imagery data quickly acquired by UAV are used to construct DEM through point cloud filtering. Then, surface subsidence information is obtained by differencing DEM from different periods. However, due to the accuracy limitations inherent in UAV photogrammetry, the subsidence data obtained through this method are characterized by errors, making it challenging to achieve high-precision ground surface subsidence monitoring. Therefore, this paper proposes a spatial domain filtering algorithm for UAV photogrammetry combined with surface deformation caused by coal mining based on the surface subsidence induced by coal mining and combined with the characteristics of the surface change. This algorithm significantly reduces random error in the differential DEM, achieving high-precision ground subsidence monitoring using UAV. Simulation and field test results show that the surface subsidence elevation errors obtained in the simulation tests are reduced by more than 50% compared to conventional methods. In field tests, this method reduced surface subsidence elevation errors by 39%. The monitoring error for surface subsidence was as low as 8 mm compared to leveling survey data. This method offers a new technical pathway for high-precision surface subsidence monitoring in mining areas using UAV photogrammetry.

Patterned Hybrid Surfaces for Efficient Dew Harvesting.

Dew harvesting, minimally influenced by climate and geographical locations, is an ideal method for addressing water shortage problems. Superhydrophilic surfaces, characterized by their highest affinity for water, are particularly attractive for this purpose as they can attract more water molecules via condensation. However, a significant challenge arises from the high surface capillary force that impedes water from sliding down and being effectively collected. The resulting water film on the superhydrophilic surface tends to stay around the edge of the water collection surface, leading to evaporation loss and reduced collection efficacy. To overcome this problem, triangular patterns with low surface adhesion to water were introduced at the edge of superhydrophilic surfaces. This modification, achieved through a wet chemical method and masked oxygen plasma treatment, has significantly improved the efficiency of water collection. Results indicate that the hybrid surface reduced the time for the first water droplet to slide down by half and increased water collection efficiency by 78% compared to uniform superhydrophilic surfaces and by 536% compared to uniform superhydrophobic surfaces under a relative humidity of 55% with a temperature difference of 15 °C. The underlying principles were elucidated through computational simulations, and the mechanisms driving the enhancement in collection efficiency were explained.

Trophic flows to mesozooplankton support the conventional paradigm of pelagic food web structure in ocean ecosystems

Abstract The current conventional paradigm of ocean food web structure inserts one full level or more of microzooplankton heterotrophic consumption, a substantial energy drop, between phytoplankton and mesozooplankton. Using a dataset with contemporaneous measurements of primary production (PP), size-fractioned mesozooplankton biomass, and micro- and mesozooplankton grazing rates from 10 tropical to temperate ocean ecosystems, we examined whether the structural inefficiencies in this paradigm allow sufficient energy transfer to support active metabolism and growth of observed zooplankton standing stocks. Zooplankton carbon requirements (ZCR) were determined from allometric equations that account for ecosystem differences in temperature and size structure. ZCRs were relatively low (∼30% of PP or less) for both oligotrophic systems and bloom biomass accumulation in eutrophic coastal waters. Higher relative ZCRs (>30% PP) were associated with elevated mesozooplankton grazing scenarios (bloom declines, abundant salps), advective subsidies, and open-ocean upwelling systems. Microzooplankton generally dominated as grazers of PP but were equal or secondary to direct herbivory as nutritional support for mesozooplankton in five of eight regional studies. All systems were able to satisfy ZCR within the conventional food-web interpretation, but balanced open-ocean upwelling systems required the most efficient alignments of contributions from microzooplankton grazing, direct herbivory, and carnivory to do so.

Enhancing Directional Droplet Transport via Surface Charge Gradient: Insights from Molecular Dynamics Simulations.

The phenomenon of spontaneous droplet transport has a wide range of implications in water collection, microfluidic manipulation, oil-water separation, and various other fields. Achieving efficient and controllable spontaneous droplet transport is therefore of paramount importance. This study investigates the potential of surface charge manipulation to enhance spontaneous droplet transport through comprehensive molecular dynamics simulations. Our findings reveal that the surface charge of the substrate significantly influences its wettability, reducing the contact angle of the droplet and increasing both the contact area and interaction energy. Moreover, we introduce a novel approach to enhance droplet mobility by creating a surface charge gradient on the substrate. By introducing bands with varying charges along a specific direction of the substrate, the droplet experiences a force directed toward regions of increasing charge, thereby facilitating its movement. Importantly, the driving mechanism of droplet motion is well explained by combining classical electrowetting theory with the analysis of the droplet's advancing and receding contact angles, which demonstrates that a more pronounced surface charge gradient generates greater force and enhances droplet mobility. These findings offer valuable insights into the design of microfluidic systems and related applications based on electrowetting.

Triboelectrically Empowered Biomimetic Heterogeneous Wettability Surface for Efficient Fog Collection.

Biomimetic engineering surfaces featuring heterogeneous wettability are vital for atmospheric water harvesting applications. Existing research predominantly focuses on the coordinated regulation of surface wettability through structural and chemical modifications, often overlooking the prevalent triboelectric charge effect at the liquid-solid interface. In this work, we designed a heterogeneous wettability surface by strategic masking and activated its latent triboelectric charge using triboelectric brushes, thereby enhancing the removal and renewal of surface droplets. By examining the dynamic evolution of droplets, the mechanism of triboelectric enhancement in the water collection efficiency is elucidated. Leveraging this inherent triboelectric charge interaction, fog collection capacity can be augmented by 29% by activating the system for 5 s every 60 s. Consequently, the advancement of triboelectric charge-enhanced fog collection technology holds both theoretical and practical significance for overcoming the limitations of traditional surface wettability regulation.

Blood pressure alteration associated with abnormal body electrolyte and water balance in colitis mice.

Previous studies reported that there is an association between abnormal body fluid balance and prognosis in colitis patients. However, it remains to be clarified the effects of colitis on characteristics of body electrolytes or water content, including alternation in blood pressure. In this study, we examined the effects of colon injury on body water balance and blood pressure in the dextran sodium sulfate (DSS)-induced colitis mouse model. We evaluated body electrolytes and water content, blood pressure, and urea-associated water conservation in DSS mice. By 5 days after the treatment, DSS mice exhibited diarrhea but relatively maintained body weight and total body sodium, potassium, and water content by increases in water intake and hepatic ureagenesis. On 7 days after DSS treatment, when colitis becomes severe, DSS mice significantly decreased food and water intake, and body weight but significantly increased relative total body sodium, potassium, and water content per dry mass. Notably, DSS induced more total body dry mass loss relative to water loss. These body electrolytes and water accumulation on day 7 were associated with a reduction in urinary osmole excretion and urine volume accompanied by renal urea accumulation. DSS mice significantly increased blood pressure by day 5 and then decreased on day 7. These findings suggest that body electrolyte and fluid imbalance and alternations in blood pressure in colitis vary with the stage and severity of the condition. Assessment and correction of electrolyte and water content at the tissue level would be important to improve the prognosis of colitis.

Experimental investigation on operational stability and its influencing mechanisms for PEMFC with dead-ended anode

Proton exchange membrane fuel cell (PEMFC) with dead-ended anode (DEA) suffers from nitrogen diffusion and water accumulation, leading to unstable performance. The core of this paper is to enhance the stability of DEA operation. By coupling the flow field structure with the DEA mode, the factors affecting the stability are explored, the performance degradation mechanism after DEA operation is revealed, and the purging strategy is formulated by combining the energy management with the voltage stability as a prerequisite. The experimental results show that the serpentine flow field is advantageous for maintaining the most stable DEA operation with a minimum voltage recession of 17.01 mV and a voltage undershoot of 11.63 mV. The local current density distribution exhibited a pattern of highest values at anode inlet and lowest at anode outlet, which could be improved by increasing operating pressure and reducing load current density. In this experiment, PCB was innovatively combined to investigate the degradation of each region of PEMFC after 60h of DEA operation. It is found that the most severe performance degradation occurs in anode outlet with a degradation rate exceeding 50%, while the center area has a degradation rate of no more than 20%.

Micrometer Groove Array Structures Inspired by Desert Grasses on Curved Substrates for Enhanced Surface Condensation Efficiency.

Drawing inspiration from the microstructures on biological surfaces to create highly efficient water-collecting surfaces is an effective way to address water scarcity. Inspired by the role of the convex and concave grooves on the surface of Namib desert grass in promoting condensation, we show that optimizing the curvature radius improves the condensation rate of droplets. This convex-concave geometry, combined with nanoneedle structures on the groove ridges, facilitates droplet merging and self-removal through jumping, refreshing the condensation site and further enhancing condensation efficiency. Meanwhile, reducing the adhesive resistance in the groove valleys accelerates droplet migration and removal. We believe this design strategy can be applied to a wide range of water collection and phase change heat transfer applications.

Anti-Frosting and Defrosting Fins with Hierarchical Interlocking Structure for Enhancing Energy Utilization Efficiency of Heat Exchanger.

Air conditioners, being an indispensable component of contemporary living, consume a significant amount of electricity every year. The accumulation of frost, dust, and water on the fins surface hinders the efficiency of the heat exchange process, thereby reducing the effectiveness of the air conditioning system. To address these limitations, this paper proposes a large-scale and cost-effective method combining compression molding, chemical etching, and spray coating to fabricate aluminum fins (HMNA) with hierarchical interlocking structures. The HMNA exhibits outstanding durability, passive and active anti-icing, anti-frosting and defrosting, and self-cleaning capabilities associated with the robust super-hydrophobicity. The hierarchical interlocking structure effectively enhances the physical and environmental durability of the HMNA. Most significantly, the frost time of the HMNA fins assembled heat exchanger is significantly delayed by ≈700% compared to the traditional Al fins heat exchanger, while the frost layer thickness is reduced by ≈75%. This greatly reduces the frequency with which the defrosting cycle is started, thus effectively improving the efficiency of the air conditioning system. The proposed method for economical and mass production of the HMNA fins can be an excellent candidate for the development of low energy consumption air conditioning system.

Radiocarbon dating of the natural groundwater in the Ob-Zaisan folded region (Russia)

Groundwater in the Ob-Zaisan folded region (Russia) has significant differences in the stable isotope composition of oxygen and hydrogen, which cannot be explained by the geographical and relief features of the region. A probable reason for these differences could be climatic changes in the study area over the past tens of thousands of years. The method of the radiocarbon dating can be perfectly suited in order to determine such small geological ages. The dating of waters using 14C data gives an understanding of their residence time. It will make it possible to differentiate periods of recharge and accumulation of water in aquifers and track the changes of the water stable isotope composition over time. The estimated water age ranges from 650 to 19,000 years. The enrichment of δD and δ18O values with the decreasing of the water age indicates a gradual warming of the Novosibirsk region climate. These results logically complement the meteorological observations over the last century and may be useful for paleoclimate reconstructions of the region.