Search Results (121)

Access to safe drinking water is a critical public health priority, particularly in arid regions such as Saudi Arabia where water scarcity and reliance on desalination present unique challenges. This study was conducted to evaluate the quality of drinking water in Madinah City and to examine the potential influence of the distribution system on water quality before it reaches consumers. Water samples were systematically collected from both primary and secondary reservoirs as well as from points within the distribution network. The samples were analyzed for key physical parameters, inorganic constituents, heavy metals, volatile organic compounds, and microbiological indicators using standard laboratory procedures. The results demonstrate that Madinah’s drinking water meets national and WHO drinking water quality standards, with most parameters well below the maximum contaminant levels (MCLs). Slight variations were observed between the primary and secondary reservoirs, likely due to the blending of desalinated seawater with groundwater. Importantly, six heavy metals—iron (115 µg/L), aluminum (48.5 µg/L), copper (58 µg/L), lead (0.22 µg/L), magnesium (7.15 µg/L), and strontium—were detected at higher concentrations in the distribution system compared to the reservoir sources (15, 15, 8.5, <0.05, and 0.71 µg/L, respectively). Although these values remained within acceptable limits, their presence suggests potential leaching from distribution pipes and underscores the need for continuous monitoring. This study provides an evidence-based assessment of water quality in Madinah, offering valuable insights for water authorities to strengthen monitoring programs and ensure long-term protection of public health. Full article

We quantitatively analyzed the effects of physical properties of metallic pipe materials on the thermal performance of firestop systems. Fire-resistance tests under realistic fire conditions were conducted for 120 min using five types of metallic pipes—carbon steel, stainless steel, cast iron, copper, and aluminum—under identical firestop material conditions. The temperature distribution at key locations within the slab and average rate of temperature increase over specific time intervals were compared. Materials with higher thermal conductivity and lower wall thickness exhibited faster thermal response characteristics. High-temperature behavior was most pronounced at the pipe surface, where copper and aluminum pipes reached temperatures approximately equal to 200 °C and 190 °C, respectively. During the initial 30 min, the average rates of temperature increase were the highest for aluminum (2.9 °C/min), followed by copper (2.2 °C/min), although the rate of heat transfer gradually decreased subsequently. A correlation analysis between the composite index of thermal conductivity and cross-sectional area, revealed a strong correlation at the pipe’s surface, with a coefficient of determination greater than 0.85. The thermal properties and cross-sectional characteristics of metallic pipes can directly affect the thermal behaviors of firestop systems. The results may serve as a basis for material-informed structural design and performance evaluation criteria. Full article

Drinking water biofilm ecosystems harbor complex and dynamic prokaryotic and eukaryotic microbial communities. However, little is known about the impact of copper corrosion on microbial community functions in metabolisms and resistance. This study was conducted to evaluate the impact of upstream Cu pipe materials on downstream viable community structures, pathogen populations, and metatranscriptomic responses of the microbial communities in drinking water biofilms. Randomly transcribed cDNA was generated and sequenced from downstream biofilm samples of either unplasticized polyvinylchloride (PVC) or Cu coupons. Diverse viable microbial organisms with enriched pathogen-like organisms and opportunistic pathogens were active in those biofilm samples. Cu-influenced tubing biofilms had a greater upregulation of genes associated with potassium (K) metabolic pathways (i.e., K-homeostasis, K-transporting ATPase, and transcriptional attenuator), and a major component of the cell wall of mycobacteria (mycolic acids) compared to tubing biofilms downstream of PVC. Other upregulated genes on Cu influenced biofilms included those associated with stress responses (various oxidative resistance genes), biofilm formation, and resistance to toxic compounds. Downregulated genes included those associated with membrane proteins responsible for ion interactions with potassium; respiration–electron-donating reactions; RNA metabolism in eukaryotes; nitrogen metabolism; virulence, disease, and defense; and antibiotic resistance genes. When combined with our previous identification of biofilm community differences, our studies reveal how microbial biofilms adapt to Cu plumbing conditions by fine-tuning gene expression, altering metabolic pathways, and optimizing their structural organization. This study offers new insights into how copper pipe materials affect the development and composition of biofilms in premise plumbing. Specifically, it highlights copper’s role in inhibiting the growth of many microbes while also contributing to the resistance of some microbes within the drinking water biofilm community. Full article

The decommissioning of the Zion Nuclear Power Plant (NPP) provided a unique opportunity to harvest and study service-aged reactor pressure vessel (RPV) beltline materials. This work, conducted through the U.S. Department of Energy’s Light Water Reactor Sustainability (LWRS) Program, aims to improve the understanding of radiation-induced embrittlement to support extended nuclear plant operations. Material segments containing the Linde 80 flux, wire heat 72105 (WF-70) beltline weld and the A533B Heat B7835-1 base metal, obtained from the intermediate shell region with a peak fluence of 0.7 × 10¹⁹ n/cm² (E > 1.0 MeV), were extracted, cut into blocks, and machined into test specimens for mechanical and microstructural characterization. The segmentation process involved oxy-propane torch-cutting, followed by precision machining using wire saws and electrical discharge machining (EDM). A chemical composition analysis confirmed the expected variations in alloying elements, with copper levels being notably higher in the weld metal. The harvested specimens enable a detailed evaluation of through-wall embrittlement gradients, a comparison with the existing surveillance data, and the validation of predictive embrittlement models. This study provides critical data for assessing long-term reactor vessel integrity, informing aging-management strategies, and supporting regulatory decisions to extend the life of nuclear plants. This article is a revised and expanded version of a paper entitled, “Current Status of the Characterization of RPV Materials Harvested from the Decommissioned Zion Unit 1 Nuclear Power Plant”, PVP2017-65090, which was accepted and presented at the ASME 2017 Pressure Vessels and Piping Conference, Waikoloa, HI, USA, 16–20 July 2017. Full article

With the proliferation of flexible electronics, the advancement of mechanically compliant thermal management systems, notably flexible heat pipes, is imperative to address evolving demands for adaptive thermal regulation in deformable device architectures. The wicks of heat pipes commonly utilize porous copper. In this study, three types of porous copper materials were fabricated: sintered pure copper powder, sintered copper powder with a copper mesh (as a reinforcing network), and sintered copper powder with NaCl (as a pore-forming agent). Their pore structure characteristics, tensile, and compressive mechanical properties were systematically investigated. Results demonstrated that incorporating NaCl into copper powder significantly increased porosity and enlarged pore size, thereby enhancing permeability. For instance, compared to sintered pure copper powder, the addition of NaCl increased the average pore diameter from 0.31 μm to 2.44 μm and improved permeability from 1.908 × 10⁻¹⁴ m² to 2.832 × 10⁻¹² m², effectively reducing fluid flow resistance. The introduction of copper mesh notably improved mechanical performance: under a sintering temperature of 900 °C, tensile strength increased from 121.6 MPa to 132.2 MPa, and compressive strength rose from 443.5 MPa to 458.4 MPa. However, NaCl-added porous copper exhibited a drastic decline in tensile strength. Consequently, NaCl-modified porous copper is unsuitable for flexible wick applications, whereas copper mesh-reinforced porous copper shows potential as a flexible wick, though further investigation is required to enhance its permeability mechanisms. Full article

The increasing power density of electronic devices drives the need for lighter, more compact heat dissipation devices. This research determines whether a hollow heat sink filled with fluid outperforms solid heat sinks for heat dissipation. Research on the integration of a heat spreader, heat pipe, and finned heat sink as a single component is limited. The copper and aluminum heat sinks consisted of a 4 × 4 fin array with a volume of 44.5 × 44.5 × 44.5 mm³. The working fluids were water and acetone with a 50% fill volume for the hollow copper and aluminum heat sinks, respectively. Each was tested at nine operating points (varying applied heats and air velocities). The hollow copper heat sink had similar overall heat sink thermal resistance while the hollow aluminum increased by 8% when compared to the solid copper heat sink, and the hollow heat sinks had a 2–9% lower fin array thermal resistance. The weight was reduced by 82% and the mass-based thermal resistance was 77% lower than the solid copper heat sink for the hollow aluminum heat sink. The considerable decrease in mass without significant loss in thermal resistance demonstrates the potential widespread application across technologies requiring low-weight components. In addition, the hollow heat sink design provides comparable or superior thermal performance to previous flat heat pipe solutions. Full article

The production of fruit brandies is based on distilling fermented fruit juices. Distillation equipment is usually made of copper. In traditional manufacturing, it consists of a boiler (batch) distiller, a boiler (pot), a steam pipe, and a condenser, all of which are made of pure copper. This study determined the corrosion parameters for copper (Cu) and Cu72Zn28 (in wt%) alloy in fermented apricot juice at room temperature. The fermentation process examined in this research utilized natural strains of yeast and bacteria, supplemented by active dry yeast Saccharomyces cerevisiae strains. This research used the following methods: open circuit potential (OCP), linear polarization resistance (LPR), and Tafel extrapolation to identify corrosion parameters. Cu had a 3.8-times-lower value of corrosion current density than brass, and both were within the range of 1–10 μA·cm⁻², with an excellent agreement between LRP and Tafel. This study proved that Cu is an adequate material for the distillation of fruit brandies from a corrosion perspective. Despite this, there are occasional reports of corrosion damage from the field. Significant corrosion impacts can arise, as evidenced by laboratory tests discussed in this paper. In the absence of a highly corrosive environment, this study indicates that, to some extent, microbiologically influenced corrosion (MIC) can influence the degradation of the equipment material. Full article

Hybrid PVT systems simultaneously produce electrical energy using photovoltaic technology and thermal energy using a heat extraction method that collects induced heat from the module. The purpose of this work is to establish a PVT system based on characterization, efficiency study, and performance analysis for both an electrical and a thermal system. A mathematical analysis of the electrical, thermal, and optical model is performed to establish the proposed system. Three types of heat exchanger pipes, including stainless steel, aluminum, and copper, are considered for a heat transfer analysis of the system. The results include temperature profiling, a comparison of the PVT system’s different components, and an overall output and efficiency study for all of the mentioned pipes. Results show that the obtained electrical and thermal efficiency for stainless steel is 0.1653 and 0.237, respectively, for aluminum it is 0.16515 and 0.2401, respectively, and for copper it is 0.16564 and 0.24679, respectively. After comparison, it was found that the overall efficiency for stainless steel is 0.40234, for aluminum is 0.40526, and for copper is 0.41244. Thus, this study will enhance the opportunity to provide an effective hybrid PVT energy management system. Full article

This study extends beyond conventional Battery Thermal Management System (BTMS) research by conducting a Life Cycle Analysis comparing the environmental impacts of two technologies: a traditional active cold plate system and an innovative passive Loop Heat Pipe (LHP) system. While active cold plate BTMS requires continuous energy input during operation and charging, leading to significant energy consumption and emissions, the passive LHP BTMS operates without external power or moving parts, substantially reducing the climate change impact. This analysis considered two materials for LHP construction: copper and stainless steel. The results demonstrated that the LHP design achieved a 9.9 kg reduction in overall BTMS mass compared to the cold plate system. The implementation of stainless steel effectively addressed the high resource consumption associated with copper while reducing environmental impact by over 50% across most impact categories, compared to the cold plate BTMS. The passive operation of the LHP system leads to substantially lower energy usage and emissions during the use phase compared to the active cold plate. These findings highlight the potential of passive LHP technology to enhance the environmental sustainability of Battery Thermal Management Systems while maintaining effective thermal performance. Full article

A hybrid cooling method for 18650 lithium-ion batteries has been investigated using both experimental and numerical approaches for electric vehicle applications. The experimental setup includes a heater section, a phase change material (PCM) reservoir, and a cooling section. The heater section simulates battery heat generation with two cylindrical aluminum housings, each sized to match an 18650 battery, two cartridge heaters, and an aluminum heat sink. An airflow channel is incorporated into the cooling section. Heat transfers sequentially from the heaters to aluminum housings, the heat sink, through three copper-water heat pipes (HPs), to/from the PCM, and finally to the cooled air in the airflow channel. This innovative design eliminates direct contact between the PCM and the batteries, unlike recent studies where the PCM has been in direct contact with the batteries. Decoupling the PCM reduces system design complexity while maintaining effective thermal management. Temperature measurements at various locations are analyzed under different heater powers, air velocities, and scenarios with and without PCM. Results show that the experimental design effectively maintains battery temperatures within acceptable limits. For a power input of 16 W, steady-state temperatures are reduced by approximately 14%, 10%, and 4% with PCM compared to without PCM for air velocities of 2 m/s, 3 m/s, and 4 m/s, respectively. A transient three-dimensional numerical model was developed in ANSYS-FLUENT to provide insights into the underlying physics. The phase change was simulated using the enthalpy-porosity approach, with computational results showing reasonable agreement with experimental data. Full article

For communities without access to uninterrupted, piped water, household water storage (HWS) practices can lead to adverse public health outcomes caused by water degradation and mosquito proliferation. With over 700,000 deaths caused by vector-borne diseases annually, the objective of this study was to determine whether water disinfectants, at concentrations deemed safe for human consumption and beneficial for water treatment, are effective in reducing the emergence of adult mosquitoes that transmit disease. Laboratory bioassays, designed to resemble the context of treating HWS containers, were conducted to assess the larvicidal effects of chemicals at concentrations below regulatory limits for drinking water: silver (20, 40, 80 μg/L Ag), copper (300, 600, 1200 μg/L Cu), and chlorine (500, 1000, 2000 ug/L free chlorine). The water disinfectants demonstrated the ability to significantly reduce the population of juvenile Ae. aegypti. Sodium hypochlorite was found to be the most effective in decreasing the survival rate of late first instar larvae, while silver nitrate exhibited the highest effectiveness in inhibiting the emergence of late third instar larvae. Ultimately, this study highlights the potential of an integrated approach to Water, Sanitation, and Health (WASH) solutions with vector control management. Full article

Acid mine drainage (AMD) forms in mining areas during or after mining operations cease. This is a primary cause of environmental pollution and poses risks to human health and the environment. The hydrographic system from the Maramureș mining industry (especially the Baia Mare area) was heavily contaminated with heavy metals for many years due to mining activity, and after the closing of mining activity, it continues to be polluted due to water leaks from the abandoned galleries, the pipes, and the tailing ponds. The mineralization in the Băiuț area, predominantly represented by pyrite and marcasite associated with other sulfides, such as chalcopyrite, covelline, galena, and sphalerite, together with mine waters contribute to the formation of acid mine drainage. The Breiner-Băiuț mining gallery (copper mine) permanently discharges acidic water into the rivers. The efficiency of iron scrap (low-cost absorbent) for the treatment of mine water from this gallery was investigated. The treatment of mine water with iron shavings aimed to reduce the concentration of toxic metals and pH. Mine water from the Breiner-Baiut mine, Romania, is characterized by high acidity, pH = 2.75, and by the association of many heavy metals, whose concentration exceeds the limit values for the pollutant loading of wastewater discharged into natural receptors: Cu—71.1 mg/L; Zn—42.5 mg/L; and Fe—122.5 mg/L. Iron scrap with different weights (200 g, 400 g, and 600 g) was put in contact with 1.5 L of acid mine water. After 30 days, all three treatment variants showed a reduction in the concentrations of toxic metals. A reduction in Cu concentration was achieved below the permissible limit. In all three samples, the Cu concentrations were 0.005 for Sample 1, 0.001 for Sample 2, and <LOQ for Sample 3. The Zn concentration decreased significantly compared to the original mine water concentration from 42.5 mg/L to 1.221 mg/L, 1.091 mg/L, and 0.932 mg/L. These values are still above the permissible limit (0.5 mg/L). The Fe concentration increased compared to the original untreated water sample due to the dissolution of iron scrap. This research focuses on methods to reduce the toxic metal concentration in mine water, immobilizing (separating) certain toxic metals in sludge, and immobilizing various compounds on the surface of iron shavings in the form of insoluble crystals. Full article

Background/Objectives: Pathogen inactivation and harmful gene destruction from water just before drinking is the last line of defense to protect people from waterborne diseases. However, commonly used disinfection methods, such as chlorination, ultraviolet irradiation, and membrane filtration, experience several challenges such as continuous chemical dosing, the spread of antibiotic resistance genes (ARGs), and intensive energy consumption. Methods: Here, we perform a simultaneous elimination of pathogens and ARGs in drinking water using local electric fields and in-situ generated trace copper ions (LEF-Cu) without external chemical dosing. A 100-μm thin copper wire placed in the center of a household water pipe can generate local electric fields and trace copper ions near its surface after an external low voltage is applied. Results: The local electric field rapidly damages the outer structure of microorganisms through electroporation, and the trace copper ions can effectively permeate the electroporated microorganisms, successfully damaging their nucleic acids. The LEF-Cu disinfection system achieved complete inactivation (>6 log removal) of Escherichia coli O157:H7, Pseudomonas aeruginosa PAO1, and bacteriophage MS2 in drinking water at 2 V for 2 min, with low energy consumption (10⁻² kWh/m³). Meanwhile, the system effectively damages both intracellular (0.54~0.64 log) and extracellular (0.5~1.09 log) ARGs and blocks horizontal gene transfer. Conclusions: LEF-Cu disinfection holds promise for preventing horizontal gene transfer and providing safe drinking water for household applications. Full article

The wall thickness of the TP2 copper tube casting billet is not uniform after a three-roll planetary rotational rolling, which affects the wall thickness uniformity of the copper tube in the subsequent process. In order to study the influence of wall thickness at different positions of copper pipe after rolling on the wall thickness of copper pipe after joint drawing, an online ultrasonic test platform was used to measure the wall thickness of copper pipe after tying, and based on the test data, a finite element model of copper pipe billet was established, and the numerical simulation of joint drawing wall thickness was conducted. Based on the results of the ultrasonic testing experiment and finite element simulation, different neural network models were used to predict the joint tensile wall thickness with the data of the ultrasonic testing experiment as input and the results of finite element simulation as output. The prediction effect of different neural network models was compared, and the results showed that the prediction and fitting effect of the SVM model was better, but overfitting occurred during the fitting process. Furthermore, particle swarm optimization is used to optimize the penalty parameter C and the kernel parameter g in the SVM model. Compared with the traditional SVM model, the PSO–SVM model is more suitable for the prediction of joint tensile wall thickness, which can better guide the production to solve this problem. Full article

Deep hot dry rock (HDR) geothermal energy is a widespread and sustainable renewable energy that could be extracted for the decarbonisation of electricity generation. Measurements are essential for hydraulic fracturing in HDR monitoring, which can be used for assessing the current state and predicting the future performance of geothermal systems. However, a major challenge is that it is difficult to implement hydraulic fracturing for HDR under high-temperature and high-pressure (HTHP) conditions. Similarly, it is hard to conduct laboratory-scale hydraulic fracturing experiments under HTHP due to the sealing failure of injection pipes in boreholes. Therefore, in this paper, we proposed a novel sealing technique by using a wedge-shaped structure for sealing injection pipes under HTHP environments. By conducting numerical simulations and experimental verifications, we discovered that (1) compression stress should be applied on the seal to achieve pre-sealing. Specifically, a compression displacement of between 2 mm and 6 mm is suggested. (2) Copper material with good ductility, high-temperature bearing performance, and excellent thermal expansion is preferred for manufacturing the seal components. (3) Heating-induced thermal expansion of sealing is conducive to re-sealing rocks. Full article