Water Accumulation Research Articles

Siphon-based scalable and salt-resistant multistage thermal desalination system

Recent advances in thermal localization-based passive solar desalination provide a great opportunity for the economical generation of freshwater, particularly in regions with insufficient energy and water infrastructure. Yet, the capillary-assisted passive desalination systems with a high-water productivity flux (measured in Lm−2 h−1) suffer from the issue of performance degradation due to salt accumulation and the inability to be scaled up. In this work, we propose siphon-based supply of saline water over the evaporator that enables scale up of the desalination system to a size significantly higher than the capillary rise height of the hydrophilic evaporator while preventing salt accumulation on the evaporator. The composite siphon comprises insulating fabric wick and a metallic grooved surface for localizing heat to evaporate a thin layer of saline liquid over the evaporator. We perform heat and mass transfer analysis to show that the thermal-to-vapor efficiency depends on the inlet mass flow rate and air gap between the evaporator and the condenser. We propose a methodology to passively control the mass flow rate to maximize the thermal to vapor efficiency at different input heat flux and initial concentration of the brine. A grooved condenser avoids mixing of brine and the freshwater, even at air gaps as low as 2 mm. A siphon-assisted 10-stage desalination system with a footprint area 15 cm × 15 cm and an air gap of 2 mm is shown to have a high water productivity flux of ∼5.73 Lm−2 h−1 from 3.5 wt% saline water at an applied heat flux 1000 W/m2, which increases to a record high distillate flux of ∼6.23 Lm−2 h−1 and thermal to water collection efficiency of ∼423 % for a 15-stage system. The ability of the desalination system to maintain a high-water productivity flux even when the evaporator area is increased by 4 times demonstrates its scalability to achieve higher desalinated water productivity rate.

Water scarcity and public health concerns in rural India: a case study of Nongpok Sekmai and surrounding villages

This study examines the critical issue of water scarcity and its impact on public health in Nongpok Sekmai and surrounding villages in India. Despite government initiatives to provide universal tap water access by 2024, these villages lack safe drinking water. Traditional sources like open wells are contaminated, and the primary river is drying up due to illegal sand mining and gravel extraction activities upstream. This situation results in a significant public health burden, with villagers facing financial strain due to waterborne diseases and the need to purchase water for basic needs. The study also examines the negative link between on-premise access to safe water and mothers' time spent on water collection. The study highlights the need for a multi-pronged approach. Renewed government efforts to implement the tap water initiative or provide alternative clean water sources like filtration plants or community wells are crucial. Additionally, stricter enforcement is needed to curb illegal mining activities and ensure river sustainability. Furthermore, exploring community-based solutions like rainwater harvesting and raising awareness about waterborne diseases and sanitation practices can empower the population. Addressing this water crisis demands a collaborative effort from the government, local communities, and environmental agencies. This study employed a mixed-methods approach, utilizing visual photographic analysis and community engagement to investigate water contamination in Nongpok Sekmai river, Manipur. The findings highlight key contamination indicators such as turbidity, algae blooms, and floating debris, while also addressing the health and social impacts perceived by the local population.

Design of Terrace-Based Hydroponic System using Hydraulic Ram Pump

The primary objective of the study is to design a terrace-based hydroponic system incorporating a hydraulic ram pump and to evaluate the effectiveness of the hydraulic ram pump in terms of drive head, flow rate, and delivery head, while also assessing its overall performance, particularly in terms of water loss percentage. The hydraulic ram pump can deliver a delivery head of 200 cm. To achieve this 200 cm delivery head, a drive head of 20 cm and a drive pipe length of 60 cm are necessary. The flow rate of the ram pump at the delivery pipe is 1.13 liters per minute. The water balance equation was employed to quantify water loss, considering parameters such as initial water volume in storage tanks, water collected in excess water collectors, and overall water losses during a system operation. The study's key findings reveal that during each 15-minute operational cycle, the terrace-based hydroponic system, incorporating a hydraulic ram pump, experienced an average water loss of 4.59 liters, equating to a 2.7% water loss percentage. This 2.7% loss could have a significant impact on sustainability if the system were to be upscaled.

GEOCHEMISTRY OF GROUNDWATERS AND SURFACE WATERS, AND GROUND ICE OF THE OKA PLATEAU, EASTERN SAYAN (RUSSIA)

The study area is located in the Eastern Sayan hydrogeological folded area. The objects of the study were groundwaters, surface waters and ground ice in the Sentsa River basin on the Oka Plateau. Cold and thermal groundwaters are associated with Proterozoic and Paleozoic metamorphic and igneous rocks. Their discharge as springs occurs in the river valleys along fault zones. Ground ice was studied in mineral frost mounds (lithalsas) composed of clays, clayey silts and silts of lacustrine-alluvial and fluvioglacial genesis. It has been established that thermal and cold groundwaters have HCO3 Ca-Na compositions, river and lake waters, as a rule, have HCO3 Ca-Na compositions, and ground ice melts – HCO3, SO4-HCO3 and NH4-HCO3 Ca. Thermal waters are largely enriched in Li, Be, B, Si, Mn, Ga, Ge, Se, As, Br, Rb, Sr, Cs, Ba and all REE relative to river and rain waters, and have the highest values of trace elements enrichment factor (EFREE). The latter shows that atmospheric precipitation participates in the formation of the composition of groundwaters (cold and thermal) and surface waters. The specificity of the geochemistry of ground ice is determined by the composition of precipitation, the injection of ice-forming groundwater from taliks, the interaction in the water-rock system, and the presence of organic matter in unconsolidated sediments. The participation of river water and groundwater in the formation of the frost mound ice core is also evidenced by similar values of stable isotopes (δ18O, δD) in surface water, groundwater and ground ice. The 3He/4He ratio points to a possible influx of mantle helium into thermal waters, and δ13С points to the magmatic and thermometamorphic mechanisms of carbon dioxide accumulation in thermal waters. The 87Sr/86Sr ratio in travertines indicates a significant contribution of intrusive rocks to the formation of fluid composition.

Integrated urban and riverine flood risk management in the Fujiang River Basin-Mianyang city

China’s monsoon climate, characterized by hot summers and substantial rainfall, leads to significant seasonal water accumulation in river basins. This often results in short-term heavy rainfall events, causing rapid water flow into river basins and subsequent flooding. River embankments, which narrow channels, exacerbate downstream flooding and pose severe safety threats. This study explores integrated urban and riverine flood risk management strategies within the Fujiang River Basin, focusing on Mianyang City. The research addresses the growing challenges of global climate change and rapid urbanization, which have intensified flood risks. Utilizing the one-dimensional Storm Water Management Model (SWMM) and two-dimensional hydrodynamic Rainfall-Runoff-Inundation (RRI) model, the study simulates flood events and urban flooding in Mianyang City and the Fujiang River Basin. These models were validated with data from hydrological stations and satellite imagery. The study evaluates extreme flood events in Mianyang City between 2015 and 2021. The findings highlight the significant role of sponge city initiatives and low-impact development (LID) facilities in mitigating flood impacts. Despite their benefits, these measures have limitations under extreme flood conditions. This study contributes to understanding the interactions between urban and riverine systems and provides a basis for improving flood risk management and resilience in rapidly urbanizing river basins. It supports ongoing efforts to implement sponge city concepts in China, offering crucial insights into effective strategies for managing flood risks in similar geographic and climatic contexts.

Unsteady numerical simulations of aircraft icing based on the dynamic grid method

In this study, an unsteady numerical simulation method based on dynamic grids was established to solve unsteady aircraft icing processes. The dual-time step method was used to achieve the time advancement of the transient airflow and droplets fields. The droplets trajectory was calculated using the Euler method, which incorporates a supercooled large droplets model. The transient evolution of the water film and ice layer on the substrate surface was considered in the icing thermodynamic model. The accuracy of the unsteady method for ice-shape prediction was verified via comparison and analysis of numerical examples. Additionally, the rime and glaze ice formation processes were explored, and the coupling effects of ice horn growth and the air convective heat transfer coefficient, water collection coefficient, and water film flow on the substrate surface were studied. The ice shapes calculated by unsteady and quasi-steady methods were compared. The results indicated that the latter predicts a larger icing range than the former. Moreover, there may be more obvious distinctions between these two methods in predicting glaze ice.

Poly(l-lactic acid) Janus Shape Memory Membranes with Uniform Vertically Penetrative Channels and Slit Pores for Enhanced Fog Collection: Synergistic Effect of Transport through Membranes and Sequential Sliding Behaviors of Water Droplets.

In this work, poly(l-lactic acid) (PLLA) Janus shape memory membranes with uniform vertically penetrative channels (SMEUVs) with slit pores have been fabricated with the help of template-assisting spray-coating and uniaxial tension at high temperature. During fog collection, superhydrophobic and hydrophilic surfaces act as the front (fog-facing) side and back side, respectively, in which the structural characteristics play essential roles. On one hand, the vertically penetrative channels in SMEUVs and the special pore geometry contribute to lower resistance, accelerating the transport of captured water through membranes (from the superhydrophobic side to the hydrophilic side). On the other hand, the movement of water droplets along the back side has been guided by the oriented structures of slit pores, promoting the detachment of droplets from the hydrophilic surface. Their synergistic effect removes captured water in a timely manner and provides fresh sites for the subsequent nucleation of water, enhancing fog collection performance. As a result, the optimal specimen (Janus SMEUVs with a draw ratio of 2.5, placed in the parallel direction) exhibits a much higher water collection rate (∼6×) relative to references (superhydrophobic and hydrophilic membranes). Our results are significant for sustainable development in view of both fog collection in arid regions and the biodegradability of PLLA.

Spontaneous continuous multiple jump of condensate droplets on superhydrophobic surface with hierarchical micro-nano structures

When two or more droplets coalesce on a superhydrophobic surface, the released surface energy will partially convert into kinetic energy, resulting in droplet jump from substrate surface. In this paper, a kind of superhydrophobic surface with hierarchical papillary micro-nano structures was fabricated to facilitate droplets coalescence-induced jump. The surface is easy to prepare without complex process. Different from single jump, a kind of spontaneous continuous multiple jump was observed on this kind of superhydrophobic surface. The influences of continuous multiple jump on condensation nucleation rate and water collection rate are investigated and a theoretical model is adopted to determine energy conversion efficiency of continuous multiple jump. The results find that continuous multiple jump makes large droplets to move spontaneously, and improves performance of superhydrophobic surface to maintain dropwise condensation even under a high subcooling. With condensing, the continuous multiple jump becomes more frequent. The average condensation nucleation rate is 303 % higher than those of surfaces without hierarchical micro-nano structures. The water collection rate on superhydrophobic surface is 2 times higher than those without hierarchical micro-nano structures. The energy conversion efficiency of continuous multiple jump is two times higher than that of single jump. This study provides a potential direction for heat transfer enhancement of condensation and self-cleaning.

Experimental Study on Water and Salt Migration and the Aggregate Insulating Effect in Coarse-Grained Saline Soil Subgrade under Freeze–Thaw Cycles

Understanding multiphase transformations and the migration of heat, water, vapor, and salt in coarse-grained saline soil under groundwater recharge and environmental freeze—thaw cycles is crucial for ensuring the stability of highway infrastructures. To clarify the water, heat, vapor, and salt migration patterns in coarse-grained saline soil, as well as the salt-insulating effect of the aggregate insulating layer, an experimental study was conducted in a soil column model under pressureless water replenishment with fluorescein-labeled liquid water under freeze—thaw cycles. The results showed that the temperature in the saline soil columns periodically changed and that hysteresis effects occurred during temperature transfer. External water replenishment and the content of liquid water inside the soil exhibited nonlinear changes with environmental temperatures. After multiple freeze—thaw cycles, two water and salt accumulation zones formed within the coarse-grained saline soil subgrade. The migration of liquid water resulted in a water and salt accumulation zone in the nonfrozen zone, whereas the migration of water vapor yielded a water and salt accumulation zone in the frozen zone. To prevent water and salt migration, a 20 cm thick gravel insulating layer could be laid at a distance of 10 cm from the bottom of the roadbed, which could provide a satisfactory salt-insulating effect. The research results provide a theoretical basis and guidance for regulating the stability of subgrades in saline soil areas.

All-day freshwater harvesting enabled by designing benzoxazine molecule with intrinsic photothermal conversion and radiation cooling ability

The importance of clean water resources for human health and economic development cannot be overlooked. Providing a way for fully passive all-day freshwater harvesting presents a significant challenge. Herein, we propose a strategy for all-day freshwater harvesting passively through a freestanding Janus film which combining solar-driven interfacial desalination during day time and dew water generation driven by passive radiative cooling at night. Specifically, the core of the strategy was a new bio-based benzoxazine which containing high-infrared emittance in the atmospheric window and the resultant cured black freestanding film owns a steady high light absorbance in the whole range of the solar irradiation wavelength. The home-made device made by the Janus film achieved a drinkable freshwater collection efficiency of 90.9 % when desalinating seawater under 1 sun illumination and achieved a dew water collection rate of 68.36 g m−2 day−1 at night. Moreover, the film has an excellent antibacterial effect, which ensures the quality of water collection and enhances the service life. Combining the advantages of bio-based raw materials, a simple fabrication process and scalability of the film, the all-day freshwater collection system makes a promising solution to alleviate freshwater shortage in many arid regions, islands and even boats sailing on the sea.

Effect of the temperature control device on the emission character of condensable particulate matter from industrial heating plant

Condensable particulate matter (CPM) is one of the major emissions of primary particles in coal combustion. The removal efficiency of CPM using the temperature control device (TCD) based on the concept of a heat exchanger application with lower capital cost was investigated in an industrial heating plant. TCD operates without water and flue gas interactions and ensures efficient control of CPM emissions, and it also minimizes the potential ion accumulation in recycled WESP water, which could otherwise hinder the removal of CPM. The total mass and chemical speciation were determined by EPA method 202. The total mass of CPM was removed by 25.7–60.6% after the TCD. The CPM captured by CPM filters (CPMspa) was down to around 15–21% and the FPM also was reduced by around 11–26%. The occurrence of vapor gradient forces and thermophoresis forces could enhance the contact between CPM and water film, which was built up on the surface of the cooling tubes during the process of TCD. Then, part of the CPM was removed with a water film. The low capital and operating cost of TCD can be installed in the industrial heating plant or be set up after the WESP in the coal-fired power plant to enhance the CPM removal efficiency.

Rainfall water collection and irrigation via stone bud and karren on karst rocky desertification slopes: Application and benefit analysis

Lack of surface water is a key factor leading to agricultural drought in karst regions and exacerbates the karst rocky desertification, which is characterized by high rate of exposed bedrock. With the characteristics of impermeability, runoff collection, and wide distribution, stone bud and karren (SBK), a unique karst landscape type composed of exposed bedrock and gullies, has a great potential to solve water shortage in agricultural irrigation, especially in the rain-rich karst regions of Guizhou Province, China. Using unmanned aerial vehicle images to identify SBK and measured rainfall–runoff data for validation, we applied SBK as a basic unit to harvest rainfall water on rocky desertification slopes and analyzed the benefits of rainfall water collection and irrigation via SBK. The results showed the following: (1) Karrens on rocky desertification slopes could be identified using a method coupling terrain opening difference and depression filling, and the simulated runoff on SBK could achieved the average NSE and R2 of 0.82 and 0.86, with RMSE and RSR less than 0.03 m3 and 0.51, respectively. (2) The exposed bedrock utilization rate and rainfall water collection coefficient of SBK were 0.62 and 0.55, respectively, such that the area ratio of exposed bedrock to the cultivated land meeting irrigation water demand reached 1:3.1, 1:3.7 and 1:7.0 under 90 %, 80 % and 50 % possibilities of irrigation. (3) Implementing SBK for rainfall water harvesting and irrigation could efficiently avoid crop failure in the karst regions where crops faced drought within only one week after rainfall, and was at an affordable cost to local farmers with limited environmental damage. The use of SBK to harvest rainfall water could also alleviate surface water shortages in karst regions caused by problems such as uneven temporal distribution of rainfall and engineering water shortages. Consequently, SBK demonstrate a strong application potential to alleviate agricultural drought in karst rocky desertification regions.

Efficient Fog-Harvesting Origami Fan.

Fog harvesting represents a promising strategy to address the global freshwater shortage. To enhance the water collection efficiency, diverse geometric structures that can effectively drive water droplet movement are essential. Inspired by the Livistona chinensis leaf, which naturally facilitates directional droplet motion through its unique gradually varying V-groove structure, we have developed a novel origami fan structure for fog harvesting through theoretical analysis. A key feature is that we can modulate the speed of droplet transport by adjusting the opening angle of the V-shaped grooves positioned at the outer circumference. Interestingly, the water collection efficiency exhibits a linear correlation with the opening angle. The highest efficiency of the origami fan can reach 5.75 times that of the control group calculated by the projected area and 3.76 times that of the control group calculated by the real area, showcasing its significant potential for enhancing water collection from fog. The simulations demonstrate that the hollow structure enhances the condensation rate of droplets, the geometric gradient of the gradual-variation V-groove drives the condensed droplets to move rapidly on the surface, and the Janus membrane permits the aggregated droplets to transit to the fan's rear side. The synergistic action of these three components ensures a clean surface for the subsequent water-collecting cycle, contributing to the high fog-harvesting efficiency. Given its simple fabrication and superior water transfer efficiency, the origami fan holds substantial promise for widespread application in the field of droplet manipulation.

Directional Transportation Behavior of Droplets on a Magnetically Responsive Micropillar Array Surface.

Technologies for manipulating droplets have applications in various fields, such as biomedical devices, chemical engineering, water collection, and thermal management. The morphology of magnetically responsive surfaces are modified using magnetic fields for inducing droplet directional rolling and bouncing. Herein, a study on the directional transport of droplets on magnetically responsive surfaces is reported, identifying three movement modes and analyzing the mechanisms influencing the transport behavior. The study explored working fluids with surface tension lower than that of water, achieving the directional transport of 30% ethanol droplets with a maximum transport velocity of 130 mm s-1. The practical applications of the droplets on a modified surface were analyzed, and methods were developed to accelerate droplet mixing. This study explored efficient operations and automation of complex chemical processes.

A-258 Hepatitis A infections among patients suspected of acute hepatitis attended in Brazilian health services

Abstract Background Millions of people worldwide are infected with Hepatitis A Virus (HAV) annually - the leading widely spread causes of acute viral hepatitis in developing countries across all continents. Objective To evaluate the prevalence of anti-HAV antibodies; to determine HAV genotypes by nucleotide sequencing in patients suspected of acute hepatitis at public healthcare institutions; and to assess the association between this infection with age, gender, region, and other risk factors Methods Between October 2019 and May 2023, we analyzed 1,562 patients with more than 18 years old with clinical suspected acute hepatitis. Results Out of the 1,562 individuals, 1,244 were seropositive for Anti-HAV IgG, a median age of 45 years (IQR: 35 to 56) vs. 31 years (IQR: 25 to 39) in non-reactive individuals (p<0.001). A higher seropositivity was found in men compared to women (p=0.002). North region showed the highest seropositivity (p<0.001). There was also an association between poor sanitation conditions and seropositivity, such as lack of sewage collection and consumption of untreated water (p<0.001), as well as an association between heterosexual orientation and higher likelihood of seropositivity (p=0.015). In the logistic regression analysis for anti-HAV IgG seropositivity, age and male sex were significantly associated with seropositivity (OR = 1.09, 95% CI: 1.08 to 1.11, p<0.001; OR = 1.56, 95% CI: 1.16 to 2.11, p=0.004). North region showed a significant increase in the odds for seropositivity compared to all other regions. For anti-HAV IgM, out of the 1,562 individuals, 97 were seropositive, significantly higher in younger individuals [median age of 34 years (IQR: 28 to 40) vs. 42 years (IQR: 32 to 54) in non-reactive individuals (p<0.001)] and in males (p<0.001). South and Southeast regions had higher seropositivity (p<0.001). Non-heterosexual orientation and more than 2 sexual partners significantly correlated with seropositivity (p<0.001). In the logistic regression analysis for anti-HAV IgM, age showed an inverse association with seropositivity (OR = 0.96, 95% CI: 0.94 to 0.98, p<0.001), being more frequent in men (OR = 1.86, 95% CI: 1.11 to 3.21, p=0.021). Consumption of seafood was significantly associated with increased odds of seropositivity for anti-HAV IgM (OR = 2.26, 95% CI: 1.43 to 3.56, p<0.001). South and Southeast regions showed more IgM positive cases than North, Northeast and Midwest regions. Among the 1,562 cases, 35 complete (or almost complete) HAV genomes were successfully recovered from metagenomics sequencing data. These genomes range from 6,625 to 7,462 bp in length (89-100% completeness), sequences were fairly similar in pairwise nucleotide alignment, classified as genotype I.A, and displaying identities ranging from 94.7 to 99.7%. Conclusions Hepatitis A infection was found among 6.2% acute hepatitis cases attended in public services in Brazil while previous infections or vaccinated patients were found in 78.9% patients. While anti-HAV IgG positive patients where most frequent in the North region of Brazil, acute hepatitis A (IgM-positive) were more frequent in South and Southeast regions. Our results reinforce the need to implement vaccination against hepatitis A among individuals with more than 18 years in our country.

دراسة عملية لاداء سخان ماء شمسي ذو الدوران الطبيعي المتصل على التوالي

This research paper presents an experimental study on the performance of a natural circulation solar water heater system with two typical collectors connected in series. The paper provides a comprehensive analysis of the system's thermal performance under different load conditions, including no-load, intermittent, and continuous load. Mean storage tank, solar collector means plate (the left) temperature and thermosyphon flow rate in a vertical tank were measured. Results showed that there was variation in solar water tank and collector plate temperature under load and no-load conditions. Analysis of thermal performance of the system was conducted for each condition. The highest plate temperature (100 ˚C or even more) with no circulation of both collector and load conditions, indicate the high quality of the solar collectors even during the cold season. The collector’s arrangement in series connection is of highest gain in energy and higher storage tank mean water temperature. Several characteristic equations obtained to represent the performance of the present natural circulation system under collector connection arrangement in series. In fact, when large amount of hot water was required for a certain purpose (Industrial sector for example - MSF plant or central heating), multiple collectors are to be deployed in series and in parallel to produce the required amount (quantity) and desired temperature (quality) at the same time. Key words: Thermosyphon solar water heater, storage tank profile temperature, Solar Water Heaters (SWHs), instantaneous efficiency, collector flow factor, collector efficiency factor, collector heat removal factor

Acoustic emission during the freezing of water or the melting of ice in aircraft

It is a frequently overlooked phenomenon that matter can produce sound emissions when undergoing a phase transition. The exact cause of this sound is until now not modeled and understood in depth, but it appears certain that sudden volume changes, cracks, friction, and other sources that occur during e.g. crystal decay/growth in melting/freezing processes must be considered. However, a generally accepted theory of the "sound of phase transitions" is lacking. In this paper we present a general introduction in this field. Besides the more fundamental aspects, the AE generation during the melting of ice can be used to detect the presence of this respective substance in technical structures. An interesting application is to detect the melting ice in aircraft. Adverse water accumulation, resulting from contamination and condensation, is regularly found in fuel tanks, and scheduled drainage procedures of this water after the melting of the ice are important to ensure the safety of systems and structures. A practical problem for drainage after flight is determining the right time to start the process. Beginning too early would mean that the remaining ice cannot be removed, and waiting too long presents an economic problem as it increases the aircraft's downtime. There is currently no technology that reports when all water has melted. To realize this goal acoustic sensors were attached to the skin of the tank walls, and the acoustic signals were intense enough to propagate through the aluminum sheets and coating and further analyzed. In this way, the completion of the melting of ice was determined by the time at which the acoustic emission stopped. We present measurements on a laboratory scale, the results from a climate chamber on relevant replica’s, and the outcome of a first campaign on an operational aircraft (Airbus A330).

Fabrication of versatile and durable superhydrophobic cotton fabrics using PTA-Ala adhesive

In recent years, the preparation of functional textiles based on polyphenols adhesion has received extensive attention and research. However, polyphenols are prone to peroxidation during oxidative polymerization, which can compromise the interfacial adhesion of their monomers. Reintroducing reactive functional groups after oxidative polymerization of polyphenols may potentially compensate for the lost interfacial adhesion while increasing cohesion. In this paper, L-alanine (Ala) is introduced into poly (tannic acid) (PTA) solution to generate the PTA-Ala via Michael addition and Schiff base reaction. Original cotton fabrics are modified with PTA-Ala solution to enhance adhesion strength between the fabrics and subsequent functional modifiers. A silver nanowire network is then incorporated to increase the surface roughness through tannic acid reduction. Finally, polydimethylsiloxane is applied to reduce fabric surface energy, resulting in superhydrophobic multifunctional OH-PDMS/Ag/PTA-Ala/cotton fabrics. The finished cotton fabric exhibits a water contact angle of 166.7 ± 1.9° and a rolling angle of 5 ± 0.5°. Moreover, the fabric features diverse functionalities such as oil-water separation, photothermal conversion, antimicrobial properties, water collection, and anti-icing capabilities, alongside excellent durability and self-healing properties that extend its service life. This finished cotton fabric demonstrates promising applications in oil pollution control, outdoor clothing and medical protection, highlighting its broad across various industries.

Groundwater in Katowice - center of a large urban and deep coal mining area in Poland

The paper presents the groundwater resources of Katowice and the results of studies conducted to identify prospective areas in aquifers with sufficient water resources for the location of public water intakes. The city of Katowice is the capital of Upper Silesia, the largest urban-industrial area in Poland, the region with a highly developed hard coal mining and many other different industries covering almost the entire scope of the economy. Due to long term drainage of mines causing the depletion and deterioration of groundwater and surface water resources, the main municipal water intakes have been located outside Katowice. Most of the pumped mine water is discharged into surface waters, causing significant salinity of water and disallow its use for municipal or industrial purposes in Katowice. The water collection and supply system is very extensive and covers a significant part of the Silesian agglomeration which is why Katowice is supplied with water from surface water intakes located outside the city. According to older published materials, such as the Hydrogeological map of Poland, there were no aquifers in the city that could have been used to supply the city with drinking water, however recent studies have shown that groundwater in the Quaternary aquifers in the western part of the city can be used to supply the city with public water. Less productive, Quaternary aquifers in north-eastern parts of the city may constitute the basis for drinking water supply in emergency situations, when surface intakes cannot be used, such as toxic, radiological or viral contamination or damage to the water supply network eg. as a result of an earthquake or warfare.

Morphological Analysis of River Characteristics in Musi Rawas Utara Regency

Effective watershed management requires the efficient collection, storage, and use of runoff water, as well as the recharge of groundwater. This study will employ morphometric analysis to determine the characteristics of the rivers flowing through one of the districts of the Province of South Sumatera, Musi Rawas Utara (Muratara). Using DEM data and GIS software, this study conducted a quantitative-descriptive analysis to obtain quantitative information about the watershed. The acquired numbers are interpreted descriptively to provide a description of the watershed's characteristics and their implications for rivers in Muratara.The eighth-order rivers of Muratara Regency are classified as major rivers. A mean bifurcation ratio (Rb) of 3.98 indicates that geological features have no effect on the typical flat drainage pattern. On average, the drainage density of the watersheds was moderate, but a few locations had a very high drainage density range, indicating their erodibility. The basins of rivers with low circularity and elongation ratios (0.19 and 0.48, respectively) are elongated and have a steep slope. The morphometric research reveals that the Muratara rivers have abundant water resources and are also predicted to experience numerous water-related disasters. Using morphometric knowledge, however, the local government could develop mitigation and planning systems for river management. Future measures must include ensuring that adequate drainage systems are in place and that all construction adheres to the principles of proper land management.