Protective Layer Research Articles

Solution-Processed Metallic Nanowire Network for Wearable Transparent Thermal Radiation Shield.

Heating requirements for residential and commercial dwellings result in significant energy consumption and deleterious environmental effects. Personal radiative thermal management textiles regulate the wearer's body temperature by controlling the material's intrinsic optical properties. Passive heating textiles suppress radiative heat losses and therefore significantly reduce the energy consumption required for building heating systems. Guided by an optical theoretical approach, a transparent radiation shield (TRS) is designed based on silver nanowires (AgNWs) that can suppress human body heat with simultaneous visible light transmittance anticipated for practical fabrics. We experimentally demonstrated a TRS with large infrared light reflectance (low emissivity of 35%) and a visible (VIS) transparency value of 75% (400-800 nm). The results are well corroborated by the Mie scattering theory and the wire-mesh equivalent sheet impedance model, which provide fundamental mechanism understanding and guidance toward higher performance. The TRS is fabricated by a simple, solution-processing method with thermoplastic elastomer protective layers, granting notable stretching capabilities, mechanical robustness, and conformability to any body shape or object. The rigorous theoretical strategy enables the scalable synthesis of low-emissivity and visibly transparent textiles for personal thermal comfort.

Synthesis and study of the inhibitory properties of a new Schiff base for C45 carbon steel in 1 M HCl

A newly Schiff base 1, 13-bis-[(4-dimethylamino) benzaldehyde 4, 7, 10-trioxatridecane-diimine] (DABT) was synthesized and characterized on the basis of the results of FT-IR, mass spectroscopy (MS), 1HNMR and 13CNMR. The desired performance of the organic compound DABT which is easy, inexpensive to prepare and eco-friendly, as a corrosion inhibitor for C45 carbon steel in 1 M HCl medium was evaluated using weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) measurements. The results suggest that the corrosion inhibition effectiveness increases with increasing inhibitor concentration and decreases with increasing temperature. The polarization experiments demonstrate that DABT exhibits the characteristics of a mixed-type inhibitor and follows the Langmuir isotherm in its adsorption behavior. Contact angle measurement revealed that the inhibitor on the surface of the carbon steel is hydrophobic. The synergistic effect of DABT has been investigated; inhibitory efficiency rises with increasing concentration of KI by competitive adsorption to form a layer of protection on the metal surface. Energy dispersive X-ray spectroscopy (EDS) combined with scanning electron microscope (SEM) was utilized to interpret the morphological study of the carbon steel surface. A good correlation was found between theoretical [Density functional theory (DFT), molecular dynamics simulation (MDS)] and experimental findings.

Quantitative risk assessment of gas leakage and explosion in open kitchens and partitioned kitchens

ABSTRACT In recent years, natural gas companies have faced more and more gas supply applications for open kitchens in China. However, natural gas cannot be utilized in open kitchens according to the current compulsory regulations. The numerical models for three typical open kitchen layouts and the corresponding partition kitchen layouts were developed, respectively. The experimental setup of gas leakage and explosion, like a residential kitchen, was established based on the similarity theory. The accuracy and reliability of numerical models have been validated by three sets of experiments. An innovative quantitative risk assessment method was proposed to quantify the integrated risks for the open kitchen layout and the partition kitchen layout. The effectiveness of the proposed risk reduction measures was assessed using a modified LOPA (i.e. Layer Of Protection Analysis). The results show that the integrated risk for the open kitchen layout in different apartments is 1.37 ~ 4.65 times than that for the partition kitchen layouts. The integrated risk of gas leakage explosion in three open kitchen layout arrangements was reduced by 94.8%, 50%, and 94.5%, respectively, by setting two layers of protection. Meanwhile, the increased expense of ¥400 can be generally acceptable for the majority of residential users. The achievements could provide theoretical and technological guidance for gas safety supply in open kitchens.

In Situ Laser-Induced 3D Porous Graphene within Transparent Polymers for Encapsulation-Free and Tunable Ultrabroadband Terahertz Absorption.

Three-dimensional (3D) porous carbon materials have great potential for fabricating flexible tunable broadband absorbers owing to their high electrical conductivity, strong dielectric loss, and unique microstructure. Herein, we introduce an innovative method for synthesizing 3D porous graphene that incorporates advanced tuning and encapsulation processes to augment its functional efficacy. Through the modulation of both thermal and nonthermal interactions between a femtosecond (fs) laser and a polydimethylsiloxane (PDMS) film, we have synergistically fine-tuned the surface morphology and lattice properties of 3D porous graphene. This approach enabled us to create a flexible terahertz (THz) absorber with customizable characteristics, boasting an impressive absorbance range of 80%-99% in the 0.4-1.0 THz spectrum, alongside a peak reflection loss (RL) of up to 35.6 dB. Furthermore, we have successfully demonstrated the production of photoinduced 3D porous graphene within a PDMS film, which serves as both a carbon precursor and protective layer. This simplifies the conventional packaging process. These devices exhibit a RL of up to 41.6 dB and an absorption bandwidth of 2.5 THz (0.6-3.1 THz). Our study presents a production methodology for high-performance, flexible THz absorbers, offering a straightforward and innovative solution for the rapid development of sophisticated, flexible THz absorbing materials.

Self-Adaptive Graphdiyne/Sn Interface for High-Performance Sodium Storage.

Efficiently reconciling the substantial volume strain with maintaining the stabilities of both interfacial protection and three-dimensional (3D) conductive networks is a scientific and technical challenge in developing tin-based anodes for sodium ion storage. To address this issue, a proof-of-concept self-adaptive protection for the Sn anode is designed, taking advantage of the arbitrary substrate growth of graphdiyne. This protective layer, employing a flexible chain doping strategy, combines the benefits of 2D graphdiyne and linear chain structures to achieve 2D mechanical stability, electronic and ion conductions, ion selectivity, adequate elongation, and flexibility. It establishes close contact with the Sn particles and can adapt to dynamic size changes while effectively facilitating both electronic and ion transports. It successfully mitigates the detrimental effects of particle pulverization and coarsening induced by large-volume changes. The as-obtained Sn electrodes demonstrate exceptional stability, enduring 1800 cycles at a high current density of 2.5 A g-1. This strategy promises to address the general issues associated with large-strain electrodes in next-generation of high-energy-density batteries.

Is Ba3In2O6 a high-Tc superconductor?

It has been suggested that Ba3In2O6 might be a high-Tc superconductor. Experimental investigation of the properties of Ba3In2O6 was long inhibited by its instability in air. Recently epitaxial Ba3In2O6 with a protective capping layer was demonstrated, which finally allows its electronic characterization. The optical bandgap of Ba3In2O6 is determined to be 2.99 eV in-the (001) plane and 2.83 eV along the c-axis direction by spectroscopic ellipsometry. First-principles calculations were carried out, yielding a result in good agreement with the experimental value. Various dopants were explored to induce (super-)conductivity in this otherwise insulating material. Neither A- nor B-site doping proved successful. The underlying reason is predominately the formation of oxygen interstitials as revealed by scanning transmission electron microscopy and first-principles calculations. Additional efforts to induce superconductivity were investigated, including surface alkali doping, optical pumping, and hydrogen reduction. To probe liquid-ion gating, Ba3In2O6 was successfully grown epitaxially on an epitaxial SrRuO3 bottom electrode. So far none of these efforts induced superconductivity in Ba3In2O6, leaving the answer to the initial question of whether Ba3In2O6 is a high-Tc superconductor to be ‘no’ thus far.

Anti-Oxidized Self-Assembly of Multilayered F-Mene/MXene/TPU Composite with Improved Environmental Stability and Pressure Sensing Performances

MXenes, as emerging 2D sensing materials for next-generation electronics, have attracted tremendous attention owing to their extraordinary electrical conductivity, mechanical strength, and flexibility. However, challenges remain due to the weak stability in the oxygen environment and nonnegligible aggregation of layered MXenes, which severely affect the durability and sensing performances of the corresponding MXene-based pressure sensors, respectively. Here, in this work, we propose an easy-to-fabricate self-assembly strategy to prepare multilayered MXene composite films, where the first layer MXene is hydrogen-bond self-assembled on the electrospun thermoplastic urethane (TPU) fibers surface and the anti-oxidized functionalized-MXene (f-MXene) is subsequently adhered on the MXene layer by spontaneous electrostatic attraction. Remarkably, the f-MXene surface is functionalized with silanization reagents to form a hydrophobic protective layer, thus preventing the oxidation of the MXene-based pressure sensor during service. Simultaneously, the electrostatic self-assembled MXene and f-MXene successfully avoid the invalid stacking of MXene, leading to an improved pressure sensitivity. Moreover, the adopted electrospinning method can facilitate cyclic self-assembly and the formation of a hierarchical micro-nano porous structure of the multilayered f-MXene/MXene/TPU (M-fM2T) composite. The gradient pores can generate changes in the conductive pathways within a wide loading range, broadening the pressure detection range of the as-proposed multilayered f-MXene/MXene/TPU piezoresistive sensor (M-fM2TPS). Experimentally, these novel features endow our M-fM2TPS with an outstanding maximum sensitivity of 40.31 kPa−1 and an extensive sensing range of up to 120 kPa. Additionally, our M-fM2TPS exhibits excellent anti-oxidized properties for environmental stability and mechanical reliability for long-term use, which shows only ~0.8% fractional resistance changes after being placed in a natural environment for over 30 days and provides a reproducible loading–unloading pressure measurement for more than 1000 cycles. As a proof of concept, the M-fM2TPS is deployed to monitor human movements and radial artery pulse. Our anti-oxidized self-assembly strategy of multilayered MXene is expected to guide the future investigation of MXene-based advanced sensors with commercial values.

Constructing Lysozyme Protective Layer via Conformational Transition for Aqueous Zn Batteries.

The practical applications for aqueous Zn ion batteries are promising yet still impeded by the severe side reactions on Zn metal. Here, a lysozyme protective layer (LPL) is prepared on Zn metal surface by a simple and facile self-adsorption strategy. The lysozyme protective layer exhibits extremely strong adhesion on Zn metal to provide stable interface during long-term cycling. In addition, the self-adsorption strategy triggered by the hydrophobicity-induced aggregation effect endows the protective layer with a gap-free and compacted morphology which can reject free water for effective side reaction inhibition performance. More importantly, the lysozyme conformation is transformed from α-helix to β-sheet structure before layer formation, thus abundant functional groups are exposed to interact with Zn2+ for electrical double layer modification, desolvation energy decrease, and ion diffusion kinetics acceleration. Consequently, the LPL renders the symmetrical Zn battery with ultra-long cycling performance for more than 1200h under high Zn depth of discharge (DOD) for 77.7%, and the Zn/Zn0.25V2O5 pouch cell with low N/P ratio of 2.1 at high Zn utilization of 48% for over 300 cycles. This study proposes a facile and low-cost method on constructing stable protective layer of Zn metal for high Zn utilization aqueous devices. This article is protected by copyright. All rights reserved.

Contacting of Bicomponent TPU-Fibers with a Conductive Core: A Method for Data Acquisition and Analysis of the Electrical Properties

With the megatrend of digitalization, the demand for sensors in previously difficult-to-access scenarios is increasing. Filament-shaped sensors (FSS) are ideal for this demand, especially in applications in which the monitoring of textile structures is the focus. Electrically conductive bicomponent filaments based on thermoplastic polyurethane (TPU) and doped with carbon nanotubes (CNTs) offer great potential due to their flexible mechanical properties. Through the core-conducting, bicomponent structure, the sensing material is protected from environmental factors such as surrounding conductive materials and external moisture. The insulating material, however, simultaneously complicates the contacting method in order to measure sensing changes in the conductive core. In this work, laser cutting is employed as a technology in order to expose the conductive core of the filaments. The filament is then coated with silver and mechanically crimped, providing both a conductive interface for the data acquisition device as well as a protective layer. Laser parameters (power 20–100 W and speed 5–50 mm/s) are investigated to identify the parameters with the best cutting properties for which the filaments are analyzed visually and electrically. This work provides a robust and reproducible method for contacting core-conducting TPU filaments for strain-sensing applications. This study shows that while the choice of laser parameter influences the morphology of the cut surface, its impact on the resulting linear resistivity is negligible.

Stabilizing Zn/electrolyte Interphasial Chemistry by a Sustained‐release Drug Inspired Indium‐chelated Resin Protective Layer for High‐areal‐capacity Zn//V2O5 Batteries

For zinc‐metal batteries, the instable chemistry at Zn/electrolyte interphasial region results in severe hydrogen evolution reaction (HER) and dendrite growth, significantly impairing Zn anode reversibility. Moreover, an often‐overlooked aspect is this instability can be further exacerbated by the interaction with dissolved cathode species in full batteries. Here, inspired by sustained‐release drug technology, an indium‐chelated resin protective layer (Chelex‐In), incorporating a sustained‐release mechanism for indium, is developed on Zn surface, stabilizing the anode/electrolyte interphase to ensure reversible Zn plating/stripping performance throughout the entire lifespan of Zn//V2O5 batteries. The sustained‐release indium onto Zn electrode promotes a persistent anticatalytic effect against HER and fosters uniform heterogeneous Zn nucleation. Meanwhile, on the electrolyte side, the residual resin matrix with immobilized iminodiacetates anions can also repel H2O and detrimental anions (SO42‐ and polyoxovanadate ions dissolved from V2O5 cathode) outside the electric double layer. This dual synergetic regulation on both electrode and electrolyte sides culminates a more stable interphasial environment, effectively enhancing Zn anode reversibility in practical high‐areal‐capacity full battery systems. Consequently, the bio‐inspired Chelex‐In protective layer enables an ultralong lifespan of Zn anode over 2800 h, which is also successfully demonstrated in ultrahigh areal capacity Zn//V2O5 full batteries (4.89 mAh cm‐2).

Stabilizing Zn/electrolyte Interphasial Chemistry by a Sustained-release Drug Inspired Indium-chelated Resin Protective Layer for High-areal-capacity Zn//V2O5 Batteries.

For zinc-metal batteries, the instable chemistry at Zn/electrolyte interphasial region results in severe hydrogen evolution reaction (HER) and dendrite growth, significantly impairing Zn anode reversibility. Moreover, an often-overlooked aspect is this instability can be further exacerbated by the interaction with dissolved cathode species in full batteries. Here, inspired by sustained-release drug technology, an indium-chelated resin protective layer (Chelex-In), incorporating a sustained-release mechanism for indium, is developed on Zn surface, stabilizing the anode/electrolyte interphase to ensure reversible Zn plating/stripping performance throughout the entire lifespan of Zn//V2O5 batteries. The sustained-release indium onto Zn electrode promotes a persistent anticatalytic effect against HER and fosters uniform heterogeneous Zn nucleation. Meanwhile, on the electrolyte side, the residual resin matrix with immobilized iminodiacetates anions can also repel H2O and detrimental anions (SO42- and polyoxovanadate ions dissolved from V2O5 cathode) outside the electric double layer. This dual synergetic regulation on both electrode and electrolyte sides culminates a more stable interphasial environment, effectively enhancing Zn anode reversibility in practical high-areal-capacity full battery systems. Consequently, the bio-inspired Chelex-In protective layer enables an ultralong lifespan of Zn anode over 2800 h, which is also successfully demonstrated in ultrahigh areal capacity Zn//V2O5 full batteries (4.89 mAh cm-2).

A “two cooking with one fish” strategy for modulating both polyaniline cathode and zinc anode towards enhanced kinetics and cycling stability for aqueous zinc ion batteries

The adverse stability of both polyaniline (PANI) and Zn anode remains a challenge to the long−term cyclability and rate capability of aqueous Zn−PANI batteries. Herein, a “two–cooking with one fish” strategy is presented to modulate both PANI cathode and Zn anode, in which nanoscale graphene sheets in cathode can promote ordered growth of PANI array, being conducive to provide large electrochemical active area and efficient transport pathways and alleviate volume variation during repeated charging/discharging process. Meanwhile, the honeycomb–like structure of graphene sheets as protective layer can accelerate zinc ion transport kinetics and suppress side reactions and zinc dendrite growth. Consequently, the optimized G/Zn symmetric cell delivers a remarkable lifespan over 1000 h at 1 mA cm−2 with 1 mAh cm−2. Furthermore, the assembled PANI/G/CC||G/Zn battery could deliver a specific capacity of 265.8 mAh g−1 at 0.2 A g−1, excellent rate capability (145.5 mAh g−1 at 20 A g−1), a maximum energy density of 246.9 W h kg−1 and power density of 8675.9 W kg−1, and especially capacity retention of 91.1 % after 10000 cycles. Combining with additional merits of low cost, eco–friendliness, and safe operation, our design will shed light on resolving the issues on cyclability and rate capability of aqueous Zn−PANI batteries.

Application of MgO/ZrO2 coating on 309 stainless steel to increase resistance to corrosion at high temperatures and oxidation by an electrochemical method

Abstract 309 stainless steel is one of the steels that have the highest resistance to corrosion and thermal oxidation compared to other steel grades, but it should not be used at temperatures higher than 980°C if there are temperature fluctuations. Additionally, 309 stainless steel is not designed for use in wet environments and has the least corrosion resistance. This study aims to cover 309 stainless steel with MgO/ZrO2 particles using a two-step electroplating deposition method and then sintering to increase its resistance to wet corrosion and oxidation in temperature fluctuations. The intermediate ZrO2 coating makes the outer MgO layer about two times thicker and reduces the corrosion current density. The morphology of the coatings was determined using scanning electron microscopy and X-ray diffraction, and oxidation resistance was determined using cyclic oxidation tests and the wet corrosion test of the corrosion solution. 3.5% NaCl was used. The results showed that the coated samples, due to the use of TiO2 middle layer and MgO protective layer in the electrochemical method, have a 2-fold increase in wet corrosion and an increase in hardness of about 77%, as well as an increase in oxidation resistance of 1.8% compared to the sample without coating. Also, the reason for using the electrochemical deposition method is for better surface smoothness and less porosity of the coating as well as its use on all metals compared to thermal spray methods.

Current status, challenges and prospects of antifouling materials for oncology applications

Targeted therapy has become crucial to modern translational science, offering a remedy to conventional drug delivery challenges. Conventional drug delivery systems encountered challenges related to solubility, prolonged release, and inadequate drug penetration at the target region, such as a tumor. Several formulations, such as liposomes, polymers, and dendrimers, have been successful in advancing to clinical trials with the goal of improving the drug’s pharmacokinetics and biodistribution. Various stealth coatings, including hydrophilic polymers such as PEG, chitosan, and polyacrylamides, can form a protective layer over nanoparticles, preventing aggregation, opsonization, and immune system detection. As a result, they are classified under the Generally Recognized as Safe (GRAS) category. Serum, a biological sample, has a complex composition. Non-specific adsorption of chemicals onto an electrode can lead to fouling, impacting the sensitivity and accuracy of focused diagnostics and therapies. Various anti-fouling materials and procedures have been developed to minimize the impact of fouling on specific diagnoses and therapies, leading to significant advancements in recent decades. This study provides a detailed analysis of current methodologies using surface modifications that leverage the antifouling properties of polymers, peptides, proteins, and cell membranes for advanced targeted diagnostics and therapy in cancer treatment. In conclusion, we examine the significant obstacles encountered by present technologies and the possible avenues for future study and development.

Milk fat globule membrane (MFGM) phospholipid - Whey protein interaction characterization and its effect on physicochemical, interfacial properties and evaluation of in vitro digestion of emulsions - Inspired by the MFGM

The interfacial composition of fat globules can change the interfacial structure and further affect the digestive characteristics. In this study, the interaction between whey protein (WP), which is the main protein added in infant formula (IF), and milk fat globule membrane phospholipid (MPL) was investigated from the perspective of simulated fat globule structure, we further characterized the physicochemical properties and the in vitro digestive performance of the emulsions. The results showed that the interaction between MPL and WP changed the secondary and tertiary structures of WP, and formed a dense protective layer at the interface of the fat globule with strong interaction, which improved the emulsification property and physical stability of the emulsion. When MPL: WP was 5:10, the emulsions showed smaller particle size, higher absolute value of zeta-potential and more uniform and stable emulsion state. In addition, during the simulated in vitro digestion of infants, the degree of lipolysis and free fatty acid release content were significantly increased, which improved the fat digestion.

Revealing the origin of enhanced structural stability for nickel-rich LiNi0.83Co0.11Mn0.06O2 cathodes in situ modified with multifunctional polysiloxane

Multifunctional polysiloxane (MPS) layer is elaborately constructed on the surface of LiNi0.83Co0.11Mn0.06O2 (NCM83) particles via in situ hydrolysis-polycondensation of tetraethyl orthosilicate. Impressively, optimal NCM83 (NCM83-2) electrode covered with average 7 nm-thickness of fresh MPS layer delivers improved capacity retention ratio of 81.8 % after 150 cycles at 25 °C and retains the value of 78.7 % after 200 cycles at 60 °C and 1.0 C. Moreover, NCM83-2 electrode presents lower polarization degree with sluggish growth of the capacity platform. The significant advantages of NCM83-2 can be interpreted by the fact that the MPS layer effectively mitigates microcracks generation by inhibiting phase transition and lattice oxygen loss. Moreover, the MPS protective layer suppresses the thickening of cathode electrolyte interphase film and boosts the structural stability of NCM83 electrode to optimize electrochemical properties. Therefore, this strategy may provide promising enlightenments for preserving structural integrity and improving interfacial stability of nickel-rich cathodes for lithium-ion batteries.

A Virus-Inspired Inhalable Liponanogel Induces Potent Antitumor Immunity and Regression in Metastatic Lung Tumors.

Pulmonary delivery of immunostimulatory agents such as poly(I:C) to activate double-stranded RNA sensors MDA5 and RIG-I within lung-resident antigen-presenting cells is a potential strategy to enhance antitumor immunity by promoting type I interferon secretion. However, following pulmonary delivery, poly(I:C) suffers from rapid degradation and poor endosomal escape, thus limiting its potency. Inspired by the structure of a virus that utilizes internal viral proteins to tune the loading and cytosolic delivery of viral nucleic acids, we developed a liponanogel (LNG)-based platform to overcome the delivery challenges of poly(I:C). The LNG consisted of an anionic polymer hyaluronic acid-based nanogel core coated by a lipid shell, which served as a protective layer to stabilize the nanogel core in the lungs. The nanogel core was protonated within acidic endosomes to enhance the endosomal membrane permeability and cytosolic delivery of poly(I:C). After pulmonary delivery, LNG-poly(I:C) induced 13.7-fold more IFNβ than poly(I:C) alone and 2-fold more than poly(I:C) loaded in the state-of-art lipid nanoparticles (LNP-poly(I:C)). Moreover, LNG-poly(I:C) induced more potent CD8+ T cell immunity and stronger therapeutic effects than LNP-poly(I:C). The combination of LNG-poly(I:C) and PD-L1 targeting led to regression of established lung metastases. Due to the ease of manufacturing and the high biocompatibility of LNG, pulmonary delivery of LNG may be broadly applicable to the treatment of different lung tumors and may spur the development of innovative strategies for cancer immunotherapy.

An Improved Synchrosqueezing S-Transform and Its Application in a GPR Detection Task

The S-transform is a fundamental time–frequency (T-F) domain analysis method in ground penetrating radar (GPR) data processing and can be used for identifying targets, denoising, extracting thin layers, and high-resolution imaging. However, the S-transform spectrum experiences energy leakage near the instantaneous frequency. This phenomenon causes frequency components to erroneously spread over a wider range, impacting the accuracy and precision of GPR data processing. Synchrosqueezing is an effective method to prevent spectrum leakage. In this work, we introduce the synchrosqueezing generalized phase-shifting S-transform (SS-GPST). Initially, it resolves the compatibility issue between the S-transform and the synchrosqueezing strategy through phase-shifting. Subsequently, the SS-GPST accomplishes spectral energy focusing and resolution enhancement via a generalized parameter and synchrosqueezing. A synthetic signal test shows that the SS-GPST excels over other methods at focusing degree, spectral resolution, and signal reconstruction accuracy and speed. In actual GPR tunnel detection data processing, we assess the adaptability of the SS-GPST from three aspects: spectral energy distribution, thin layer identification, and data denoising. The results indicate: (1) compared to other methods, the SS-GPST accurately expresses spectral components with a strong focusing degree and fewer interference components; (2) high-frequency slices of the SS-GPST accurately detect the top and bottom interfaces of a 3.0–3.5 cm reinforcement protection layer; and (3) due to fewer interference components in the SS-GPST spectrum, reconstructing GPR profiles through the SS-GPST inverse transform is an efficient denoising technique. The SS-GPST demonstrates adaptability to different data processing purposes, offers high-resolution T-F spectra, and shows potential to supersede the S-transform.

Geophysical and physicochemical assessment of groundwater and the implication on the public health in rural and semi-urban areas of Northern Nigeria

Groundwater resource plays a central role in every sector of life globally. Unfortunately, the roles of groundwater are often unappreciated in many parts of the world, especially in developing nations. The paper applied a combined geo-electrical method and hydrochemical analysis alongside physical surveys to investigate aquifer promising zones, the quality and the source of water supply in the selected regions. The geo-electric resistivity data were used to select the most aquifer-promising zone for groundwater development with a key interest in groundwater potential and aquifer overburden protective capacity overlying the water-bearing unit. Seventeen (17) vertical electrical sounding (VES) acquired in four regions reveals that the regional weathered/fractured unit which constitutes the aquifer unity extends from 13.4 m to 41.3 m in depth with the subsurface resistivity value varying between 53 Ωm–1013 Ωm in terms of resistivity values. The overburdened thickness (protective soil layers) stretches from 2.5 m to 13 m with a resistive layer of resistivity values ranging from 111 Ωm to 2877 Ωm, which could provide high aquifer protective cover for the regional groundwater systems. The computed aquifer transmissivity and hydraulic conductivity range from 0.54 m2/h\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${m}^{2}/h$$\\end{document}–15.85 m2/h\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${m}^{2}/h$$\\end{document}, and 0.95 m/day–9.19 m/day, respectively. The estimated average longitudinal conductance (0.2 moh) reveals that the regional groundwater systems are moderately protective against surface contaminants. In addition, the physicochemical water analysis was examined, which exposes the level of heavy metals (HMs) compositions in the regional groundwater systems and the possible public health risks compared to WHO permissible drinking water limits. The sample water from the Rivers had the highest concentration of HMs (0.089 mg/I–2.012 mg/l), followed by the hand-dug wells (HWDs) (0.033 mg/l–1.555 mg/l) and the lowest in the borehole (0.011 mg/l–0.511 mg/l). In contrast, the borehole water sample shows a moderation where the HMs presence falls within the WHO standard for drinking water. The outcomes of the study show that 63% of the investigated region consumed water with a high concentration of HMs above the WHO permissible standard allowance for drinking water, while only 37% took water that falls within the WHO permissible standard. In conclusion, the study showed significant impacts of anthropogenic activities on the regional water quality, which provides vital information about the regional groundwater systems and the quality of water supply for adequate groundwater development and sustainability.

Analisis Of Upgrading Low-Crested Structures As An Adaptation Measure To Climate Change For Coastal Protection: A Hybrid Approach

Coastal zones have consistently been among the most appealing settlement areas due to their proximity to the sea, rich natural resources, and the high quality of life they offer (Lamberti et al., 2005). However, these regions are affected by climate change impacts, such as sea-level rise, storm surges, and an increased intensity of extreme weather events (Burcharth et al., 2014). Traditional low-crested rubble mound breakwaters are commonly used to protect coastal areas from wave damage. However, it is expected that the variability of climate conditions will induce a loss of functionality and structural integrity in the coming decades. Coastal communities and coastal managers, within the framework of sustainable development, are demanding new approaches that include not only the preservation of the hydraulic performance of the breakwaters, but also other factors, including social and environmental impacts. These requests significantly affect the traditional way to conceive those structures to be integrated into the coastal landscape. To cope with the variation of climate drivers, existing low-crested breakwaters must be adapted to accommodate social demands and environmental issues. Therefore, upgrading and maintaining the existing rubble-mound breakwater is a hot topic in coastal engineering, and deserves special attention due to the possible intensification of external loads resulting from the impacts of climate change (Stagnitti et al., 2023). Upgrading can be done by modifying the structure profile and/or adding structure elements (Burcharth et al., 2014). In 2011, Cappietti provided curves for the functional design of submerged breakwaters to be used in place of preexisting emergent breakwaters. Burcharth et al. (2014) explained that the best way to improve the structure is to put an additional layer of protection on the front slope, as long as the foreshore has a mild slope of around 1:100. But if the foreshore becomes steeper because of erosion, then a front berm will also be needed. Stagnitti et al. (2022) introduced a novel methodology based on the calculation of the failure probability during a lifetime due to independent failure modes. Their method was employed to evaluate the performance of upgraded breakwaters in response to climate change. Estimating the wave overtopping of both existing and upgraded breakwaters is essential for designing upgrade options that can ensure the safety of port operations. Stagnitti et al. (2023) applied the numerical model IH2VOF, which was calibrated using experimental data, to study the wave overtopping of damaged and upgraded rubble-mound breakwaters. The present work examines the feasibility of converting emerged rubble-mound breakwaters into submerged breakwaters to minimize their detrimental environmental effects. To achieve this goal, an investigation was conducted to evaluate the hydraulic performance of submerged breakwaters that are created by lowering the crest of existing emerged breakwaters. Additionally, two-dimensional numerical simulations were performed using IH2VOF to investigate wave interactions with the structures.