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To determine the feasibility of β-diversity measures to evaluate the impact of salinity stress on community homogeneity in marine environments, a 1-month bioassay was conducted using the protozoan assemblage as the test community. The test samples were collected using the slide method in coastal waters of the Yellow Sea, northern China. Five treatments were designed according to a salinity gradient of 9, 19, 29, 39, and 49 PSU. The homogeneity of the test community showed significant variability in both composition and abundance patterns among five treatments. The multivariate dispersion measure on compositional data was linearly associated with the salinity stress compared to those on abundance alone or in combination with occurrence. The traditional β-diversity index represented a different behavior from that of the multivariate dispersion measures. These findings suggest that the composition-based multivariate dispersion may be a useful tool to evaluate the global salinity stress on community homogeneity in marine ecosystems. [ABSTRACT FROM AUTHOR]

In order to investigate the properties of seawater mixing alkali-activated materials, the development law of hydration reaction, mechanics and corrosion resistance of seawater alkali-activated materials based on multi-component composite cementitious materials was studied. The results show that seawater mixing has a certain inhibitory effect on the hydration reaction of alkali-activated slag, and the compressive strength of SLCM at different ages also shows a decreasing trend to a certain extent, which is not conducive to the development of strength. Fly ash and silica fume can reduce the hydration reaction rate, early strength and toughness of the seawater alkali-activated materials, but their strength and toughness increase potential is significant in the later period, in which the strength and toughness growth rate of the silica-fly ash-slag terpolymer system from 7 days to 28 days reaches 50. 9% and 86. 7%, respectively. Compared with alkali-activated slag, adding fly ash and silica fume can improve the electric flux permeability and chloride ion mobility coefficient of alkali excited materials in seawater to a certain extent, which is consistent with their microstructure, but the three still belong to the same chloride ion permeability grade, i. e., medium permeability grade (electric flux method). [ABSTRACT FROM AUTHOR]

Electrochemical seawater splitting faces competing chlorine evolution reactions and chlorine corrosion, proposing significant obstacles to commercial applications. In this work, a feasible strategy is developed for the simultaneous oxidation of SO42− and CoFe LDH to form an intercalation SO42−/CoFe LDH, which achieves excellent OER performance (265.2 mV@100 mA cm−2) and satisfactory stability (1000 h@500 mA cm−2). The presence of SO42− is found to enhance the intrinsic activity of CoFe LDH and reduce the corrosion tendency of CoFe LDH. In situ Raman and selected area electron diffraction results demonstrated that CoFe LDH and SO42− are simultaneously generated and inserted into the LDH interlayer. DFT calculations further confirmed that the insertion of SO42− reduced the tendency of Cl− adsorption, which improved the OER selectivity. Finally, in the flow AEM electrolyzer, the SO42−/CoFe LDH and Pt/C system exhibited a voltage of only 2.264 V at 500 mA cm−2 and achieved stable operation in natural seawater for 150 h. The working efficiency in natural seawater is as high as 55.0% with the price per GGE H2 as low as $1.211, which is promising for a wide range of applications. [ABSTRACT FROM AUTHOR]

[Display omitted] The development of efficient and stable catalysts for oxygen evolution reaction (OER) in seawater presents a major challenge for hydrogen production through water electrolysis. In this work, we present a stable NiFe foam catalyst with a Se-doped Ni/Fe oxide surface prepared through a combination of chemical vapor deposition and electrochemical exfoliation. This method effectively modifies the surface of the commercial NiFe foam to a rough and stable Se-doped Ni/Fe oxide surface, displaying exceptional OER performance in both freshwater and seawater with more than 54 days stability in natural seawater. Characterizations reveal Ni-Se doped Fe oxide surface, with subsurface layers consisting of Ni alloyed with a moderate concentration of Fe, optimizes the adsorption free energy of oxygen-containing intermediates. Our results demonstrate a surface engineering approach to activate NiFe foam as a robust OER catalyst for seawater electrolysis, which is beneficial for the hydrogen economy and for the environment. [ABSTRACT FROM AUTHOR]

Construction of a proper electron donor-acceptor (D-A) microenvironment through introducing a suitable chemical moiety is an effective strategy to facilitate photogenerated charge transfer in a cascade step actively, which can boost the corresponding photocatalytic performance significantly. Herein, a series of naphthalenediimide (NDI y), possessing unique electron-deficient aromatic imides, were introduced to prepare D-A structured g -C 3 N 4 (CN) derivative hybrid photocatalysts for photocatalytic hydrogen evolution (PHE) from water splitting. Remarkably, the modification with NDI y all significantly improved the PHE performance, in which 1%NDI NH2 @CN exhibits the best photocatalytic activity (14.57 mmolꞏg−1ꞏh−1), exceeding 5.6 times over the unmodified pure CN under the same conditions. The enhanced PHE activity is highly associated with the interfacial D-A interactions between NDI y and CN , which also lays the foundation for the further rational design of analogs toward various types of photocatalytic reactions. [Display omitted] • Electron-deficient NDI y moiety was introduced to construct hybrid photocatalysts. • Optoelectronic properties of x%NDI y @CN were precisely regulated. • Modification of NDI y enhances the PHE performance both in freshwater and seawater. • 1%NDI NH2 @CN exhibits the best PHE activity, exceeding 5.6 times over pure CN. [ABSTRACT FROM AUTHOR]

Background: Actinomycetes are a well-known example of a microbiological origin that may generate a wide variety of chemical structures. As excellent cell factories, these sources are able to manufacture medicines, agrochemicals, and enzymes that are crucial. Results: In this study, about 34 randomly selected Streptomyces isolates were discovered in soil, sediment, sea water, and other environments. Using a qualitative fast plate assay, they were tested for L-glutaminase production, and nine of them produced a significant amount of pink L-glutamine. Streptomyces sp. strain 5 M was identified by examining the 16S rRNA gene in the promising strain G8. A pH of 7.5, an incubation temperature of 40 °C, and the use of glucose and peptone as the carbon and nitrogen sources, respectively, produced the highest quantities of L-glutaminase. The molecular weight of the isolated L-glutaminase was estimated to be 52 kDa using SDS-PAGE analysis. At pH 7.5 and Temp., 40 °C, the isolated enzyme exhibited its highest levels of stability and activity. The isolated enzyme's Km and Vmax values were 2.62 mM and 10.20 U/ml, respectively. Strong toxicity against HepG-2, HeLa, and MCF-7 was observed due to the anticancer properties of the isolated L-glutaminase. Conclusion: Our findings include the discovery of Streptomyces sp. strain 5 M, which yields a free L-glutaminase and maybe a possible applicant for extra pharmacological investigation as an antineoplastic drug. [ABSTRACT FROM AUTHOR]

Submerged or partially floating seagrasses in marine or brackish waters form productive seagrass beds, feeding grounds for a rich and varied associated biota, play key ecological roles in mitigating climate change and provide ecosystem services for humanity. The objective of this study was to perform a temporal quali- and quantitative analysis on the scientific production on seagrasses in the Atlantic Ocean during last 64 years (1960 to 2024) through defined workflow by scientometric analysis on Scopus database. Publications in this database date back to 1969, comprising a total of 3.482 scientific articles, primary focused on seagrass ecology. These articles were published in 574 distinct peer-reviewed scientific ecological journals, and are divided into four periods based on the number of articles, keywords and biograms, with an average annual increase of 8.28% in the number of articles published. Zostera marina , Halodule wrightii and Thalassia testudinum were the most researched species, especially in Atlantic coastal areas of Europe and North/Central America. Studies on seagrasses along the Atlantic coast have been well consolidated by a few authors with prolific scientific output, but much of the research has been conducted by non-specialists who published only one or a few articles. We also found that researches from each continent tend to focus on specific topics: North America researches investigated future climate change scenarios and seagrass ecology, while those from Europe prioritize on restoration plans. Additionaly, European researchers from Europe predominantly collaborate with local scientists, a trend also observed among American researches. This indicates a need for increase research and scientific production in the South Atlantic region. [ABSTRACT FROM AUTHOR]

The paper explores the doxologies in the book of Amos, arguing that they articulate a polemical viewpoint distinct from prevailing biblical and ancient Near Eastern notions about the formation of the sea, mountains, wind, and God's abode. Central to the comprehension of this cosmogony is the recurring phrase in Amos 5:8d and 6:9c, "(He) who summons the waters of the sea and pours them on the surface of the earth." While previous scholars have understood this phrase as referring to the primeval Flood, a tsunami event, or Levantine torrential rain, the present paper suggests a cosmogonic interpretation, in line with its context. Subsequent elements in the same series of texts are interlinked with this portrayal, emphasizing the unified—and polemical—perspective of the doxologies. This new explanation also has ramifications for the dating and composition of the doxologies in the book of Amos. [ABSTRACT FROM AUTHOR]

A novel and rapid method to determine 90Sr activity in seawater by proportional counter has been developed. Precipitation of 90Sr and radiochemical separation were investigated. 90Sr was precipitated in the form of oxalate to remove the dominant salts present in seawater and then radiochemical separation was performed by using Sr-resin. The chemical recovery of 90Sr (75–95%) was determined gravimetrically using a stable primary Sr2+ solution. The minimum detectable activity (MDA) of 90Sr was determined to be 0.025 Bq L−1 for 1 L seawater sample for 2 h counting time using ultra-low background proportional counters. The validation of the method has been performed by using the samples from the IAEA-RML-2021 and IAEA-RML-2019 proficiency tests organized by International Atomic Energy Agency (IAEA).ı [ABSTRACT FROM AUTHOR]

Benzene, toluene, ethylbenzene, and xylene (BTEX) can be found in marine and estuarine waters due to accidental spills of oil and derivatives, as well as in production water and effluents discharged from petrochemical plants. Addressing the bioremediation of these compounds in saline environments and effluents with elevated salinity levels is imperative. In this study, the halotolerance of Aspergillus niger was assessed by subjecting it to a stepwise increase in salinity, achieved through progressive addition of NaCl from 2 to 30‰ (v/v). The fungal strain exhibited optimal growth support up to a salinity concentration of 25‰, accompanied by a biomass production rate of (0.93 ± 0.11) g.d-1. The adapted biomass was employed in batch reactors to evaluate the biodegradation of BTEX (1,500 mg.L-1). In the absence of sucrose, the reactors inoculated with fungi demonstrated almost complete BTEX removal within 7 days, with rates ranked as follows: benzene (1.12 d-1) > toluene (0.78 d-1) > ethylbenzene (0.65 d-1) > xylene (0.63 d-1). Enhanced BTEX removal rates were obtained in the presence of sucrose, notably with 2 g.L-1: benzene (3.63 d-1) > toluene (2.10 d-1) > ethylbenzene (1.56 d-1) > xylene (1.50 d-1). Notably, benzene was found to be the sole compound adsorbed onto the fungal mycelium (1.50 ± 0.19) to (13.35 ± 4.72) mg.g-1 of biomass. [ABSTRACT FROM AUTHOR]

Heavy metal and nitrogen contaminations are serious concerns in aquatic environments. Marichromatium gracile YL28, a marine purple sulfur bacterium, has shown great potential as a bioremediation agent for removing inorganic nitrogen from marine water. This study further investigated its ability to simultaneously absorb heavy metals, including Pb(II), Cu(II), Cd(II) and Cr(VI), and remove inorganic nitrogen. The contributions of photopigment and extracellular polymeric substances (EPS) in the YL28 biofilm to heavy metal adsorption and tolerance were also evaluated. The YL28 biofilm demonstrated higher adsorption efficiencies for heavy metal ions than planktonic cells. A high level of EPS was detected in the biofilm. The effects of four heavy metal on the inhibition of photopigment synthesis showed that high concentrations of Cu(II) greatly inhibited the production of BChl a and Car. The adsorption efficiencies of Pb(II), Cu(II), Cd(II), and Cr(VI) in the YL28 biofilm reactor reached 86.59%, 72.94%, 80.06%, and 95.95%, respectively. Elevated concentrations of heavy metal ions only marginally impeded ammonia nitrogen removal; they impacted neither nitrite and nitrate removals nor hindered the simultaneous elimination of three inorganic nitrogen compounds. Coupled with their ability to remove inorganic nitrogen, the high adsorption capacity and tolerance of YL28 biofilms toward heavy metal suggest a promising solution for mitigating metal pollutants. [ABSTRACT FROM AUTHOR]

Tides represent the daily alternations of high and low waters along coastlines and in oceans, and the current theory (termed the gravitational forcing mechanism) explains them as a manifestation of the response of ocean water to the Moon's (Sun's) gravitational force. However, although the purely hydrodynamic models representing the current theory have been widely tested over global ocean, their tidal elevation accuracies are generally low. This implies an uncertainty as to whether the gravitational forcing mechanism is the best explanation for tides. In this study, we present a new theory (termed the oceanic basin oscillation-driving mechanism), in which tides are explained as a manifestation of oscillating ocean basin that is intricately linked to the elongated spinning solid Earth due to the Moon (Sun). Based on this new theory, we develop an algebraic tide model and test it using 11-year observations from 33 bottom pressure stations over the Pacific Ocean, the average root mean square (RMS) deviation of tidal elevation predicted by this model against observation is 7.54 cm. Using a ratio of M2 elevation RMS of ocean tide model EOT11a and its total tidal elevation RMS as a reference, we estimate the total tidal elevation RMS of six purely hydrodynamic models [i.e., Hallberg Isopycnal Model (HIM), OSU Tidal Inversion Software-GN (OTIS-GN), STORMTIDE model (STORMTIDE), OSU Tidal Inversion Software-ERB (OTIS-ERB), STM-1B, and HYbrid Coordinate Ocean Model (HYCOM)] to be 59.93, 51.64, 57.05, 38.56, 86.92, and 53.56 cm, respectively. [ABSTRACT FROM AUTHOR]

Maritime accidents frequently occur in the Philippine archipelagic waters, often resulting in significant loss of life. These incidents highlight the urgent need for improvements in the country's maritime safety systems. By utilising accident data from the Philippine Coast Guard and the GISIS IMO databases, spatial analytical approaches were employed to determine incident distribution patterns and resulted in an overall depiction of the likelihood component of risk across the country's territorial waters. Kernel density and hotspot analysis revealed areas where incidents were concentrated and where statistically significant hotspots occurred. The Maxent tool was used to develop risk likelihood models for the incident locations using environmental rasters representing wind speed, significant wave height, depth, surface current, land distance and port distance. Model performance metrics including the AUC, TSS and Kappa were used to compare the two datasets and provide confidence on model robustness. Variable contribution figures showed that land distance is the most influential variable, with the majority of high-risk areas predominantly located near population centres. The resulting maps provide an intuitive and informative depiction of the characteristic patterns of maritime accidents in the country, identify areas of high risk requiring immediate attention and offer valuable insights to support strategies for improving and enhancing the country's maritime safety. [ABSTRACT FROM AUTHOR]

(1) Background: To date, data concerning the population of Alosa immaculata and Alosa tanaica from the marine waters of Bulgaria are rather scarce. In the range of a project for mapping the Bulgarian marine protected sites from the network NATURA 2000, we provide an intense investigation of the biology and distribution of both Alosa species. (2) Methods: A trawling survey was carried out within 102 predefined sampling plots of 10 × 10 km grid cells (93 cells on the continental shelf, up to 100 m depth, and 9 offshore cells). In some coastal regions, sampling was conducted with gill nets of different mesh sizes (28 mm to 36 mm). Analysis of the suitability of the occupied habitat of both species was carried out using the MAXENT v 3.4.0 software application. The status of the populations was studied based on the parameters abundance (ind./km−2), biomass (kg/km−2), size, sex structure, maturity, and food spectrum. (3) Results: Out of 102 transects studied, A. immaculata was found in 12 transects and A. tanaica in 13. A total of 408 fish specimens were captured, out of which 313 were A. immaculata and 95 were A. tanaica. Both species were distributed along Bulgaria's entire Black Sea coast, with a numerical prevalence of the catches in the southern part. The population size of A. immaculata for the number of individuals on a biographical level in the Marine Black Sea Biographic Region (MBLS) was a minimum of 100,255 individuals and a maximum of 526,408 individuals (the average was 313,286). The population size for A. tanaica was a minimum of 28,183 individuals and a maximum of 449,549 individuals (an average of 238,866). The current population density of A. immaculata in the MBLS was 25.98 ind./km−2, and for A. tanaica, it was 19.00 ind./km−2. The current biomass of the population of A. immaculata in the MBLS was 3.44 kg/km−2, and the population of A. tanaica was 0.53 kg/km−2. The sex ratio for A. immaculata was 1 male:2.6 females, and for A. tanaica, 1 male:3.8 females. Both shad species were feeding with less intensity or not feeding during the winter. The diversity in the food spectrum of A. tanaica was more limited compared to that of A. immaculata. (4) Conclusions: Key parameters for the Bulgarian Black Sea Exclusive Economic Zone indicate current stability in the resources of A. immaculata and A. tanaica and more favorable conditions for the populations in the Natura 2000 sites compared to that outside the Natura 2000. The results of this study should be used to develop management plans for marine protected areas, and future monitoring projects should follow the sampling protocol. [ABSTRACT FROM AUTHOR]

This study addresses the challenges of and opportunities for achieving the ambitious greenhouse gas emissions reduction target of the fishery sector of the Republic of Korea, set at 96% by 2030. We also focus on the current status of land-based aquaculture and underground seawater resource development, quantitatively compare energy inputs for land-based fish cultivation, and evaluate the potential of underground seawater to reduce CO2 emissions. Since 2010, 762 underground seawater boreholes have been developed, yielding a cumulative daily pumpage of 125,780 m3. Jeollanam-do was found to have the highest daily pumpage, with an annual energy requirement of 131,205,613 Mcal. Despite the fact that the energy demands for underground seawater are higher in some months, it provides a 22.6% reduction in total annual energy consumption compared to surface water. The use of underground seawater for heating or cooling resulted in a 24.1% reduction in the required input energy. However, energy requirements increase due to the relatively high surface water temperature in some regions and seasons. This study also highlights the utilization of underground seawater in heating or cooling surface water via indirect applications using geothermal heat pumps. This innovative research broadens the methods of greenhouse gas mitigation, particularly in the agriculture, livestock, and fisheries industries. [ABSTRACT FROM AUTHOR]

MoS2 coating is a newly developed method to prevent bolt corrosion and the seizure of bolts used in equipment in sea areas. It is of great significance to investigate the evolution of the tensile properties and intact coatings for the maintenance of coated bolts. To evaluate the tensile properties of MoS2-coated titanium alloy bolts, titanium alloy bolts coated with MoS2 (TC4+MoS2) and bolts treated with a composite treatment of anodizing oxidation and MoS2 coating (TC4+AO+MoS2) were corroded in salt spray tests for 4300 h. The MoS2 coating significantly enhanced the bolts' corrosion resistance, demonstrating exceptional protective performance by only experiencing minor peeling due to oxidation-induced cracking of the coating during the extensive 4300 h salt spray test. The tensile strengths of the TC4+MoS2 and TC4+AO+MoS2 bolts both decreased as compared with the original bolts. The bolts pretreated with anodic oxidation revealed lighter coating peeling and maintained a higher tensile strength after corrosion. Therefore, it can be concluded that the coatings provided excellent corrosion resistance, leading to a minor impact on the bolts' tensile strength and fracture behavior under the synergistic damage of sea water corrosion and preloading. [ABSTRACT FROM AUTHOR]

The aim of this study is to verify the possibility of detecting oil in the bottom sediment using a fibre optic system. The presence of oil is assessed on excitation–emission spectra obtained from spectral fluorescence signals of the sediment sample. A factory spectrofluorometer coupled with an experimental fibre optic measurement system was used. During the determination of spectra, the fibre optic system is set at a 45° angle to the sediment surface and placed above its surface. The light exciting the fluorescence and the light emitted by the sediment are transmitted in a combined bundle of fibre optic threads. The analysis of excitation–emission spectra of sediments contaminated with oil shows variability of the shapes of fluorescence spectra depending on the type and degree of oil contamination, which indicates the feasibility of the sensor design for detecting oil in the sediment in situ. [ABSTRACT FROM AUTHOR]

The delayed eukaryote evolution during the mid-Proterozoic may have been linked to prolonged low oxygen levels during this period. Two short oxygenation events have recently been identified at ca. 1.57 Ga and ca. 1.4 Ga, but the redox conditions during the intervening interval remain poorly constrained. In this study, we conducted mineralogical and geochemical investigations on three sections of the Wumishan Formation (ca. 1.52-1.47 Ga) that were deposited between the two oxygenation events in the Yanliao basin. The results revealed two distinct changes in carbonate mineralogy and precipitation style associated with concurrent changes in carbonate I/(Ca + Mg): a transition from intervals with positive I/(Ca + Mg) anomalies and abundant watercolumn carbonate mud to intervals with no I/(Ca + Mg) anomalies and abundant seafloor precipitates, suggesting a shift from suboxic to anoxic conditions in shallow seawater. In both of the suboxic intervals, I/(Ca + Mg) values reached 0.5-2.6 µmol/mol, with negative Ce anomalies (Ce/Ce*(SN) = 0.69; data from literature) occurring in the later interval (ca. 1.48 Ga). The results suggest significant redox fluctuations in the shallow seawater during the Mesoproterozoic. However, these pulsed oxygenation episodes may not have been sufficient to sustain the continuous evolution of early eukaryotes. [ABSTRACT FROM AUTHOR]

The crustacean family Ampithoidae is one of the most abundant invertebrate families associated with macroalgae in shallow marine waters. Ampithoe, the largest genus, was previously documented as non‐monophyletic by phylogenetic analyses based on morphological and molecular characters. Here, we reconstructed a multi‐gene phylogeny of Ampithoidae with the first data of the southwestern Atlantic Ocean. We performed the first biogeographic analyses for the family, which indicated its origin in the Indo‐West Pacific, with subsequent dispersion to the Atlantic Ocean around the Eocene. Divergence times suggest that the diversification of Ampithoidae is congruent with the brown algae crown radiation, which allowed the colonization of new environments. [ABSTRACT FROM AUTHOR]

The synthesis of new functionalized silica gel with immobilized thiosemicarbazone fragments by the reaction of aldehyde silica gels with thiosemicarbazide in an ethanol medium in the presence of a catalytic amount of hydrochloric acid is described. The material was characterized by thermogravimetric analysis and infrared spectroscopy data. Effective solid-phase extraction of Sn(II) and Hg(II) using synthesis organomineral material—silica with immobilized thiosemicarbazone fragment has been demonstrated. Determination of Sn(II) and Hg(II) in samples whose matrix excludes the possibility of direct ETAAS (electrothermal atomic absorption spectrometry) determination, for example in sea waters, an approach has been proposed to replace the matrix of the analyzed sample with a sorbent matrix based on modified silica. ETAAS conditions for the determination and preconcentration of Sn(II) and Hg(II) in the sorbent used with slurry sampling have been described. The proposed methodology for determination Sn(II) and Hg(II) was tested on the example of sea water of the Black Sea, fresh tap water and mineral drinking water "Esentuki." The error of determination was no more than 10% rel. The detection limit for mercury was 50 ng/L, tin 7 ng/L. The concentration factor is 100 for both elements. The advantage of the developed ETAAS approach for the determination of mercury and tin in comparison with other spectroscopic methods (ICP-AES, ICP-MS) is shown. [ABSTRACT FROM AUTHOR]

The water budget components of an atmospheric column are precipitation, evaporation, and horizontal water vapor divergence. This study finds that when precipitation from the Global Precipitation Climatology Project (GPCP), evaporation from the SeaFlux product, and water vapor divergence from ERA5 are employed, the degree of budget closure depends strongly on the location and time period. Variations in this error are not random, and this study seeks to better understand these biases as the climate system evolves. Errors are particularly significant over ocean regions in and near the west Pacific warm pool, where there are multiyear budget residuals of roughly 10% of the magnitude of precipitation. Biases in other tropical ocean basins are more seasonal and smaller in magnitude. Time-varying budget errors are strongly linked to variations in convective organization that vary with the large-scale environment; errors correlating with deep organized rain show coefficients of 0.62 and 0.56 in the west Pacific and central Pacific, respectively. Errors are linked to a lesser extent with cloud microphysical structures in the East Indian. Both factors affect rainfall retrievals through well-known precipitation bias mechanisms (beam-filling, convective/stratiform effects). Characteristics of the large-scale environment that produce changes in convective organization and precipitable ice water content are explored. [ABSTRACT FROM AUTHOR]

Aluminum alloy plays a powerful role in construction industries, particularly automotive, aircraft and shipbuilding. This study analyses the corrosion behaviour of the friction stir welded, dissimilar aluminium alloy (AA6061 and AA8011) by laboratory immersion test method with different corrosion mediums (with two acidic nature solutions and one alkaline nature solution) in atmospheric temperature. Each specimen of the base metals AA6061, AA8011 and the weld zone area are immersed separately in 3 wt% HCl, 3 wt% H2SO4 and seawater under 25 days is the exposed time. The weight loss method was employed in the computation of corrosion rate. The experimental observations reveal that the weld zone of the specimen possesses more corrosion resistance compared to the base metals. The specimens immersed in the seawater got lesser weight loss than other solutions. The SEM analysis clearly shows that the base metal of AA8011 has been fairly affected on its surface by corrosion attack and 3D Laser profilometry scan images of the specimens visually show its corrosion. [ABSTRACT FROM AUTHOR]

AbstractThe sector-field–inductively coupled plasma–mass spectrometry (SF-ICP-MS) technique was applied for the quantification of toxic metals in microplastic particles (MPs) from seawater of six coastal sites from the Barents and White Seas following a microwave-assistant leaching with 30% HNO3. The mean repeatability of the method (relative standard deviation) was 1–4%, and intermediate precision averaged 4–7% for all metals. The dependence of metal content on the MPs size was also of immense consideration. The developed method can be recommended as a standard tool for accurate and precise microplastic analysis with important geochemical and environmental implications. [ABSTRACT FROM AUTHOR]

We examined the potential of environmental DNA (eDNA) for identifying tsunami deposits in the geological record using lake-bottom sediments in the Tohoku region, Japan. The presence of eDNA from marine organisms in a lacustrine event deposit provides very strong evidence that the deposit was formed by an influx of water from the ocean. The diverse DNA assemblage in the deposit formed by the 2011 Tohoku-oki tsunami included DNA of marine origin indicating that eDNA has potential as an identifying proxy for tsunami deposits. Subsequently, we examined the applicability of eDNA for recognizing paleo-tsunami events using the deposits formed by the 869 CE Jogan tsunami and a prehistoric event (2400–2900 cal year BP). The taxa detected in the tsunami deposits were markedly different from those of the background sediments. Many taxa that were represented in the Jogan tsunami deposit were also detected in the layer immediately above the tsunami deposit. This layer was indistinguishable from the overlying peat by visual observation, but the eDNA results suggest that it is likely to be a muddy tsunami deposit. The results of this study indicate that eDNA has the potential to elucidate the origin of event deposits that have been difficult to identify. [ABSTRACT FROM AUTHOR]

The marine carbon cycle has a central role in biogeochemical cycling and a close interaction with the climate system. Here, we use the stable carbon isotope (δ 13C) of particulate inorganic carbon (PIC) and particulate organic carbon (POC) in marine particles to diagnose carbonate dissolution and organic matter respiration processes in the ocean water column. We show PIC dissolution both in the euphotic zone, potentially driven by POC remineralization, and a preferential dissolution of coccoliths compared to foraminifera below the saturation horizon in the water column. Within the oxygen deficient zone (ODZ), POC remineralization and consequent respiration-driven PIC dissolution are both significantly diminished. We also demonstrate that POC remineralization preferentially removes a 13C-enriched component compared to isotopically-light bulk POC in both the large size fraction (LSF, > 51 μ m) and small size fraction (SSF, 0.5 – 51 μ m) of the pump particles, but exhibits a greater impact on the large particles because of its smaller inventory. Simultaneously, addition of a 13C-enriched heterotrophic or chemoautotrophic component to the SSF further increases the isotopic offset between SSF and LSF POC. Overall, this study uses δ 13C to provide novel evidence for different biogeochemical processes in marine particles, and demonstrates carbonate dissolution in the ocean water column, both driven by bulk seawater chemistry and organic matter respiration within particles. The absence of O 2 in the ODZ likely protects carbonate from dissolving by severely limiting organic matter respiration, thus reducing shallow PIC dissolution within the ODZs. [ABSTRACT FROM AUTHOR]

Atlantic sturgeon Acipenser oxyrinchus oxyrinchus is widely distributed along the Atlantic coast of North America, with spawning populations extending from the St. Lawrence River, Quebec to the St. Marys River, Georgia-Florida. At one time, Atlantic sturgeon supported lucrative fisheries on adults within rivers where they spawned and on subadults and adults within coastal waters. Because of decimated population sizes, Atlantic sturgeon in U.S. waters are now federally protected as five Distinct Population Segments (DPS) under the U.S. Endangered Species Act. While juvenile Atlantic sturgeon are resident within their natal rivers, subadults and adults are highly migratory in coastal waters and often occur in non-natal estuaries, exposing them to a variety of anthropogenic threats outside of their natal estuaries, including bycatch. To most effectively protect the smallest and most vulnerable populations, a method is needed to accurately identify the population origin of individual specimens and their aggregations outside of their natal systems. In this study, microsatellite DNA analysis was used to identify the genetic population structure of Atlantic sturgeon across 13 reference populations. Their genetic profiles then were used to identify the population origin of individuals collected from six coastal locales and one non-natal estuary. All 13 reference collections harbored genetically distinct, and in some cases more than one, population of Atlantic sturgeon. The Hudson River was by far the largest contributor to the overall coastal and non-natal estuarine collections, at 35.3%. The contributions of the other reference populations varied considerably between < 1.0% (York, Edisto, Savannah, and Satilla rivers) to 15.6% (Saint John River) and 12.9% (James River) and appeared unrelated to their estimated population sizes. These results suggest that migratory behavior in marine waters varies greatly among Atlantic sturgeon populations, and should assist resource managers assess the effects of anthropogenic stressors on sturgeon outside of their individual natal river or DPS. [ABSTRACT FROM AUTHOR]

Environmental context: External nutrients giving rise to critical ecological issues of the coastal seawater. We investigated the nearshore nutrient concentrations and their sources in Xiamen Bay during 2013–18. Our results could provide theoretical support for controlling nearshore nutrient pollution. Rationale: External nutrients greatly increase the critical ecological risks of the coastal seawater. Therefore, it is important to understand the sources and variation characteristics of nitrogen (N) and phosphorus (P) in the coastal area. Methodology: The dissolved inorganic nitrogen (DIN) and phosphate (PO4–P) in coastal Xiamen were monitored from 2013 to 2018. The input of nitrogen from runoff in the coastal Xiamen was calculated from the runoff flow amount collected by Xiamen Marine and Fisheries Bureau. Atmospheric dry deposition of DIN was simulated using Williams model to analyse the potential sources of nutrients in the coastal Xiamen. Results: High DIN and PO4–P levels occurred in the inner bay and decreased dramatically outside Xiamen Bay. The lowest values of DIN and PO4–P were observed in summer, which is consistent with the temporal variation in nutrient inputs from the surface runoff and atmospheric deposition. The nutrient input of Jiulong River is the main source of eutrophication for Xiamen Bay, providing more than 4 × 104 tonnes (Mg) of N input per year. The atmospheric N dry deposition provided more than 2.2 × 103 Mg of DIN input per year, which accounts for ~3.4–6.3% of the Jiulong River DIN input in the coastal Xiamen. Discussion: The ratio of atmospheric nitrogen deposition to nitrogen enrichment from Jiulong River varied from 0.21 to 0.40, indicating that atmospheric nitrogen deposition was an important contributor to the coastal nutrient in Xiamen. This study provides an insight into the major sources of N and P and highlights the importance of atmospheric nitrogen deposition to the DIN in the coastal city Xiamen. Environmental context. Nutrients from external sources are related to critical ecological issues in coastal seawater. We investigated the nearshore nutrient concentrations and their sources in Xiamen Bay, China during 2013–2018. Our results provide support for the need to control sources of nearshore nutrient pollution. (Image credit: Siying Dai.) [ABSTRACT FROM AUTHOR]

The effect of different extraction processes on the properties of Typha leaf fibers was investigated. In this work, manual decortications (FNT), NaOH alkali treatment (FT), sea water retting (FM) and a combined treatment (FC) including NaOH plus enzyme Pectinex Ultra SPL were compared. After the extraction process, morphological structure was examinated, physical and mechanical properties were also discussed. Scanning electron microscopy results revealed that extraction of Typha leaf fibers by NaOH plus enzyme led to removal of surface impurities and non-cellulosic materials. According to X-ray diffraction results, crystallinity index of (FC) was improved after enzymatic process by 57% compared to manual decorticated fibers. Tenacity of Typha fibers improved after different extraction methods when compared to manual decortications. Especially sea water retting process (FM) showed an increase of 82% higher tensile strength. Moreover, attenuated infrared spectroscopy analysis revealed that chemical retting, sea water process and combined treatment caused change of chemical composition by disappearing and/or attenuation of some bands which belong to hemicelluloses and lignin compounds. Also, chemical constituents' analysis presents lignin fraction and alpha cellulose equal to 8.13% and 69.8% respectively for (FC). [ABSTRACT FROM AUTHOR]

An in situ shipborne detection device was developed and applied to the detection of manganese ion (Mn2+) in the offshore seawater. A sealed chamber design was used for insulating against the seawater corrosion. And under the control of computer, the device would be run without any manual intervention. The waste would be collected and follow further treatment. The sensitivity of the device was investigated with a limit of detection (3σ/S) of 1.0 ppb between the concentration 0 and 200 ppb. The stability of the device also examined with a RSD of 4.6% (n = 10), and the device worked well last a month with the same electrode. Finally, the in situ shipborne detection device has been successfully applied for the determination of Mn2+ in seawater around Xiamen Island. A series of optimizations would be carried out so that the shipborne detection device will be more suitably applied to the determination of heavy metal ions in seawater in the future. [ABSTRACT FROM AUTHOR]

Treatment of extremely saline water such as the brine rejected from reverse osmosis water desalination plants, and produced water from shale oil and non-conventional gas extraction, is considered a global problem. Consequently, in this work, hollow fiber membrane distillation (HFMD) is experimentally evaluated for desalinating extremely saline water of a salinity ranging from 40,000 to 130,000 ppm. For the purpose of comparison, the HFMD is also tested for desalinating brackish (3000–12,000 ppm) and sea (25,000–40,000 ppm) water. Firstly, the HFMD is tested at two values of feed water temperature (65 and 76 °C) and flow rate (600 and 850 L/h). The experimental results showed that the HFMD productivity significantly increases when the temperature of feed water increases. Increasing the feed water flow rate also has a positive effect on the productivity of HFMD. It is also concluded that the productivity of the HFMD is not significantly affected by increasing the salt concentration when brackish and sea water are used. The productivity also slightly decreases with increasing the salt concentration when extremely saline water is used. The decrement in the productivity reaches 27%, when the salt concentration increases from 40,000 to 130,000 ppm. Based on the conducted economic analysis, the HFMD shows a good potential for desalinating extremely saline water especially when the solar collector is used as a heat source. In this case, the cost per liter of freshwater is reduced by 21.7–23.1% when the evacuated tube solar collectors are used compared to the system using electrical heaters. More reduction in the cost per liter of freshwater is expected when a high capacity solar-powered HFMD plant is installed. [ABSTRACT FROM AUTHOR]

The subpolar North Atlantic (SPNA) is crucial in the global ocean circulation system and one of the few regions where deep convection occurs. The intermediate and deep waters formed in the SPNA have long been investigated, yet their sources and pathways are not fully understood. In this study, we employ a combination of two radionuclide tracers, namely, 129I and 236U, to understand water mass provenance and mixing in the SPNA. The concentrations measured between Portugal and Greenland and across the Labrador Sea in 2020/2021 agreed with previously observed tracer distributions. The highest tracer concentrations were measured in the East Greenland Current (EGC), Denmark Strait Overflow Water (DSOW), and, to a lesser extent, in the eastward-flowing Labrador Sea Water (LSW). In contrast, waters of southern origin such as the North East Antarctic Bottom Water and North East Atlantic Central Water (ENACW) carried comparably smaller amounts of 129I. By using a binary mixing model, we estimated that the EGC contains about 29%–32% of the Polar Surface Water outflowing the Fram Strait. DSOW was mainly derived from 20% to 35% Return Atlantic Water and mixed with LSW. The Iceland Scotland Overflow Water (ISOW) evolved into North East Atlantic Deep Water in the Irminger and Labrador seas primarily by mixing with LSW and, to a lesser extent, with DSOW. The 129I and 236U binary mixing approach was less conclusive for LSW, reaching the current limitation of the model. This study suggests potential benefits and limitations of using 129I and 236U to investigate the mixing and provenance of water masses in the SPNA. [ABSTRACT FROM AUTHOR]

BACKGROUND: Conventional treatment processes and existing photocatalysts have proven insufficient in efficiently removing aldrin and dieldrin. Consequently, this study aimed to investigate the removal of aldrin and dieldrin from surface water using a titanium dioxide/graphene oxide/copper ferrite (TiO₂/GO/CuFe₂O₄) nanocomposite. RESULTS: The highest photodegradation efficiencies for aldrin (100%) and dieldrin (99%) were achieved with a TiO₂/GO/CuFe₂O₄ nanocomposite dosage of 1.3 mg L−1, at a sunlight intensity of 9 W m−2 and an optimal photodegradation time of 25 min. The maximum UV absorption wavelength of the TiO₂/GO/CuFe₂O₄ nanocomposite was observed at 365 nm. The quantum yield of the nanocomposite was recorded as 2.69 × 102 mol einstein−1, and its bandgap energy was determined to be 3.31 eV. The first‐order kinetic rate constants for aldrin and dieldrin were calculated as 0.05 and 0.047 min−1, respectively. X‐ray diffraction analysis confirmed the crystal structure of CuFe₂O₄/TiO₂, while Fourier transform infrared spectroscopy detected carboxylic, epoxy, carbonyl and other oxygenated groups within the TiO₂/GO/CuFe₂O₄ nanocomposite. Scanning electron microscopy and transmission electron microscopy images revealed that CuFe₂O₄ was situated on the outer layer of GO. Energy‐dispersive X‐ray analysis identified the elemental composition of the TiO₂/GO/CuFe₂O₄ nanocomposite as comprising GO, C, Cu, Fe, Ti and O. A reusability study demonstrated that the nanocomposite maintained excellent performance, achieving 99% removal efficiency after 79 cycles and 97% after 100 cycles. CONCLUSIONS: The TiO₂/GO/CuFe₂O₄ nanocomposite effectively removed aldrin and dieldrin from surface water. This nanocomposite holds promise for the remediation of other aquatic ecosystems, such as bays, rivers and ocean waters. © 2024 The Author(s). Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

This study puts forward a reliability analysis for the bearing performance of piles subjected to the coupled action of chloride corrosion and scouring. A chloride diffusion model was constructed based on the stiffness degradation factor and Fick's law. The Monte Carlo simulation method, along with the consideration of the scouring effect of water flow on the pile foundation, was employed to assess the impact of key factors on the failure probability, considering both the bending moment and lateral displacement damage criteria. The results show that for the same exposure period, the failure probability increases as the bending moment, lateral and vertical loads, and seawater velocity increase; furthermore for the same conditions, the failure probability increases with longer exposure times. According to a particular case study, the mean bending moment, mean lateral and vertical loads, and seawater velocity all have an impact on the lateral displacement failure criterion, making it more sensitive than the bending moment failure criterion. [ABSTRACT FROM AUTHOR]

A novel and highly promising Ag2S-P2MA nanoribbon photocathodes are synthesized using a single-step technique based on 2-mercaptoaniline oxidation with (NH4)2S2O8 and AgNO3. This process yields polymer composites with nanoribbon morphologies, typically 150 nm wide and ranging from 500 to 1,000 nm in length. These nanoribbons exhibit excellent absorbance across the entire optical spectrum up to 780 nm. The fabricated Ag2S/P2MA photocathode is designed for water splitting to generate hydrogen gas using two different electrolytes: natural Red Sea water and artificial seawater free from heavy metals. This variation allows observation of the impact of seawater's heavy metals. Hydrogen gas production is studied using a three-electrode cell with linear sweep voltammetry at room temperature. In both electrolytes, the photocurrent is measured at 0.015 mA/cm2. However, both the current density in light (Jph) and dark (Jo) values decrease in artificial seawater compared to natural seawater, with values of −0.033 and −0.017 mA/cm2 in natural seawater and −0.027 and −0.012 mA/cm2 in artificial seawater. The Ag2S-P2MA nanoribbon photocathodes exhibit stable behavior, producing hydrogen at a rate of 12 µmol/cm2 h. Combined with their cost-effectiveness and potential for mass production, this positions them as viable candidates for commercial electrode applications in various industrial settings. [ABSTRACT FROM AUTHOR]

The livelihood of small-scale fishers is highly dependent on marine resources and coastal areas while the condition of marine waters is increasingly unpredictable due to seasonal uncertainty and extreme weather due to climate variability. This condition has a negative impact on fish catches and the income of small-scale fishermen. The study results were obtained through interviews with respondents using a structured questionnaire. Sampling was carried out using multistage random sampling based on the type and number of ships controlled (1 GT-5GT). The total sample of respondents interviewed was 166 fishing households, consisting of 36 respondents from Bandar Lampung City, 65 respondents from South Lampung Regency, and 65 respondents from Tanggamus Regency. Data was evaluated using three analysis methods, namely household income structure, indicators of income vulnerability, and adaptation mechanisms. Income structure and income vulnerability use a quantitative approach, while adaptation mechanisms use a qualitative approach. The results of this empirical study found that the source of income of traditional capture fisher households is from: fishing business (on the farm) averaged 82.22%, in Tanggamus Regency, the proportion reached 86.22%. The income vulnerability index of traditional capture fisher households (LVI-IPCC value) in Bandar Lampung City and South Lampung Regency is positive (0.39 and 0.36). The income vulnerability index of traditional fishermen in Tanggamus Regency is negative -0.29. Fishermen employ an adaptation mechanism that engaged the five fundamental facets of income capital, namely natural capital, human capital, physical capital, financial capital, and social capital. [ABSTRACT FROM AUTHOR]

In this work, a screen-printed ionic liquid-graphene electrode (SPIL-GrE) was fabricated and characterised for electrochemical detections of cadmium (Cd2+) and lead (Pb2+) using square wave voltammetry (SWV). Characterizations by scanning electron microscopy and Raman spectroscopy verified the presence of multilayer graphene sheets mixed with carbon nanoparticles. From SWV measurements under an optimal condition, the anodic currents for Cd2+ and Pb2+ of SPIL-GrE were 4.2 times and 1.4 times as high as those of a conventional screen-printed carbon electrode. In addition, the SWV currents of SPIL-GrE for Cd2+ and Pb2+ dissolved in 0.1 M HCl electrolyte solution (pH 1.0) were linear in the range of 250–2,500 ppb. The detection limits (3S/N) for Cd2+ and Pb2+ of SPIL-GrE were as low as 150 and 93 ppb (1.3 and 0.5 µM), respectively. Besides, the Cd2+ and Pb2+ peak currents of SPIL-GrE were negligibly interfered by the additions of Na+, K+, Mg2+, Ca2+, Co2+, Mn2+, Ni2+ and Fe3+ ions at the concentration 10 times as high as that of Cd2+ and Pb2+. Moreover, a single SPIL-GrE displayed good repeatability with the relative standard deviation (RSD, n = 10) of 8.7% and 4.1% for SWV peak currents towards 1,000 ppb (8.9 µM) Cd2+ and 1,000 ppb Pb2+ (4.8 µM), respectively. Furthermore, SPIL-GrEs produced in the same batch exhibited good reproducibility with RSD (n = 7) of 8.9% and 5.5% for 1,000 ppb Cd2+ and 1,000 ppb Pb2+, respectively. Lastly, the determination of Cd2+ and Pb2+ in fresh and sea water samples using the developed method statistically agreed well with the results of inductively coupled plasma atomic emission spectroscopy. [ABSTRACT FROM AUTHOR]

Given that hexavalent chromium ions (Cr(VI)) are among the most biologically toxic heavy metal ions in the environment, it would be desirable to develop approaches that are easy-to-use, practical, and cost-effective for monitoring Cr(VI) content in environmental matrices. Herein, we report a colorimetric assay for Cr(VI) detection based on the oxidase-like activity of a series of nanoscale substituted transition metal vanadates (STMVs) with the general formula M3V2O8, where M represents divalent metal cations such as Ni2+, Cu2+, and Zn2+. The structural and physicochemical characterisations indicated that mesoporous Cu3V2O8 and Ni3V2O8 with roughly nano-spherical morphologies were successfully formed with monoclinic and orthorhombic phases, respectively. In addition, micro/mesoporous Zn3V2O8 had uniform hexagonal nanosheets with an orthorhombic crystalline phase. The UV-vis spectroscopy showed that Cu3V2O8 and Ni3V2O8 oxidised O-phenylenediamine (OPD) to 2,3-diaminophenazine (DAP); however, Zn3V2O8 did not exhibit the desired activity. Under the optimised reaction conditions, a simple, fast, and low-cost colorimetric sensor was designed based on the outstanding oxidase-like activity of Cu3V2O8 (Vmax = 0.25 µM s−1) to detect Cr(VI). The Cu3V2O8/OPD system operated selectively for Cr(VI) against other ions, and the lowest detectable [Cr(VI)] within the linear range of 2–32 μM was 0.24 μM, which is lower than the standard Cr(VI) levels (0.96 µM) for drinking water set by the World Health Organisation (WHO). This colorimetric technique was also applicable for assessing Cr(VI) in untreated tap water and Caspian Sea water samples. The analytical results showed that mesoporous Cu3V2O8 reliably developed a sensitive colorimetric system with thermal stability for the determination of toxic ions in water sources based on an intrinsic oxidase mimic. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA, 4,4'-(propane-2,2-diyl)diphenol) is a common plasticizer that is very widespread in the environment and is also found at significant concentrations in the global oceans, due to contamination by plastics. Here we show that triplet sensitization is an important degradation pathway for BPA in natural surface waters, which could prevail if the water dissolved organic carbon is above 2–3 mgC L−1. Bromide levels as per seawater conditions have the potential to slow down BPA photodegradation, a phenomenon that could not be offset by reaction of BPA with Br2•− (second-order reaction rate constant of (2.54 ± 0.09) × 108 M−1 s−1). Ultra-high resolution mass spectrometry revealed that the presence of inorganic salts (NaCl and NaBr) markedly increased the complexity of the observed CHO product compounds formed upon photosensitized degradation of BPA. The obtained results suggest that bisphenols can be efficiently removed by photosensitized reactions and generate higher number of oligomers and polyaromatic compounds in the sea surface and liquid water of marine aerosols compared to freshwaters and/or dilute cloud-water. Considering that polyaromatic compounds absorb solar actinic radiation, these results suggest that inorganic salts could significantly affect the photosensitized degradation of bisphenols and consequently influence the light-absorbing properties of marine aerosols and, ultimately, the Earth's radiative balance. [ABSTRACT FROM AUTHOR]

In the present work, acrylonitrile-butadiene-styrene (ABS)/glass fiber (varying fiber orientation angle) and with different % of carbon black (CB) particles-based hybrid composites are fabricated by hot press compression molding technique. Prepared composites were examined under marine conditions in sea water medium and erosion behavior under erodent particles entrained in gas fluid and found reduced impact. Morphological studies are studied through scanning electron microscope. Material removal mechanism is found to be micro-cracking at the impingement angle of 90°. Additionally, numerical analysis for the composite material with respect to single particle impact for erosion was conducted using LS-DYNA. [ABSTRACT FROM AUTHOR]

Biological sources are significant contributors to aquatic soundscapes. Soniferous fish can dominate the soundscape in certain locations, at specific times and frequencies, particularly during the production of choruses. Passive acoustic monitoring of fish choruses can provide important ecological information about soniferous fish populations. This study presents the Australian Fish Chorus Catalogue, an inventory of fish choruses detected from 83 locations in Australian estuarine and marine waters. The Australian Fish Chorus Catalogue contains data on fish chorus occurrence and the spectral and temporal measurements, spectrographic images, and audio examples of 301 fish choruses. This catalogue has been developed to establish the foundations of an ongoing effort to document, quantify, compare, and track Australian fish choruses. We hope this open-access data depository will be used as a reference for future research and will facilitate an increase in understanding of fish choruses, which can then be applied to the monitoring and management of fish populations and their respective ecosystems. [ABSTRACT FROM AUTHOR]

This review examines the occurrence and fate of microplastics (MPs) in freshwater, marine, and terrestrial environments in South Africa. MPs were found in Tshwane and Johannesburg in drinking water samples, with concentrations as high as 0.189 particles/L. Concentrations in freshwater bodies were greater, sometimes reaching 0.33–56 particles/L. MP levels in marine sediments were greater than many worldwide averages, particularly along the southeast coast (up to 45,867 particles/kg) and the MP levels in air were 1–5 particles/m3. These values are in line with figures around the globe which stand at 0.1–10 particles/L, and 0.3–10 particles/m3 for water, and air respectively. Low-density PE, PP, and PE-HD were the most prevalent polymers identified. Although there is little data, inappropriate disposal of waste is a major cause of soil contamination, which is a serious concern. The study highlights how important it is to conduct more research to close knowledge gaps, especially regarding MPs in groundwater and their impact on human health. The findings emphasise the necessity of improved wastewater treatment technologies, public awareness initiatives, and stronger laws governing single-use plastics. Standardizing MPs detection techniques, improving our knowledge of MPs fate and transport, and estimating the effects of MPs exposure to human health should be the main goals for future research. Effective cooperation between researchers, legislators, and industry is necessary for mitigation initiatives to be successful. [ABSTRACT FROM AUTHOR]

Hydrogen evolution in alkaline condition is kinetically unfavorable and requires active and stable electrocatalysts, not to mention the complex composition of seawater in catalytic alkaline seawater electrolysis. Herein, highly dispersed Pt on CoP nanoarray (denoted as Pt/CoP) is decorated as a hydrogen evolution electrocatalyst and further improved its activity by modulating the binding interaction between free Cl− in alkaline seawater and Pt/CoP. Compared to the blank control without Cl−, which requires an overpotential of 76 mV, this cathode exhibits an overpotential as low as 39 mV to reach −100 mA cm−2 after the addition of NaCl to the electrolyte. Characterizations and theoretical simulations demonstrate that Cl−coordinates with Pt species and strengthen the intermediates adsorption by reducing the electropositivity of the Pt sites. Furthermore, by coupling the Pt/CoP cathode with Ir/CoFe‐LDH anode, whose activity can also be boosted by Cl anions, the assembled seawater electrolyzer only required 1.75 V to 1 A cm−2 and stably operate for over 100 h. This work presents a major leap in electrode development for ultra‐high performance seawater electrolysis, highlighting that Cl−, which is generally considered detrimental, can be effectively harnessed. [ABSTRACT FROM AUTHOR]

Performing organic reactions in water, particularly in seawater under sunlight, is a desirable objective in chemistry because both are the most abundant and cheapest resources on the Earth. Herein, we describe a simple and useful hierarchical assembly based on host–guest interactions that yields tunable macrocycle (cucurbit[10]uril, Q[10])-based hybrid single-layer 2D supramolecular-organic-framework nanosheets (POM@Q[10]-SOFs) in water. The resulting 2D hybrid assemblies as heterojunction photocatalysts offer multiple electron transfer pathways for the generation of chlorine radicals (˙Cl) in aqueous solution, thereby facilitating highly selective photooxidation of the inert C(sp3)–H bonds of toluene to benzaldehyde at room temperature, even in seawater under sunlight. Notably, control experiments revealed that Q[10]-SOFs play a pivotal role in the photocatalytic process, which can be attributed to the viologen in Q[10]-SOFs acting as an electron acceptor and transfer station, effectively promoting the separation of electron–hole pairs within the integrated 2D hybrid assemblies. This work demonstrated the rational application of seawater in organic reactions. [ABSTRACT FROM AUTHOR]

The overburden of marine hydrate sediment is usually a permeable cover, and the presence of permeable overburden directly affects the depressurization effect. However, previous studies have mainly focused on the effect of the permeable overburden without considering seawater infiltration, and the influence of seawater infiltration on the production of hydrate cannot be ignored. In this article, a new numerical model considering seawater infiltration is developed and this study is completed by numerical simulation. The results show that seawater infiltration significantly reduces hydrate dissociation, and the presence of seawater substantially reduces cumulative gas production and increases water production compared to non-permeable overburden, with higher permeability resulting in lower gas production and higher water production. It is an effective means to extract hydrates through lower bottom-hole pressure by increasing the gas–water ratio. It is of great significance to further understand the production characteristics of hydrate reservoirs. [ABSTRACT FROM AUTHOR]

ABSTRACT While dolomitization by normal seawater has been commonly used to explain the formation of Cenozoic dolomites, ancient platform‐scale dolostones are normally interpreted as being products of either evaporative brines or mixed fresh and marine fluids. However, the viability of these two models in ancient successions is continuously questioned by new studies which favour normal or slightly modified seawater as the dolomitizing fluid. This study presents an ancient example from the lower Cambrian Longwangmiao Formation (South China) which, although appearing to have formed in association with evaporite minerals and experienced meteoric subaerial exposure, was interpreted to be dolomitized by normal seawater. Three petrographic types of dolomites, formed in the penecontemporaneous to early burial diagenetic stages in the Longwangmiao Formation. These include finely, fine to medium and medium to coarse crystalline dolomites. The stable isotope compositions (δ13Ccarb, δ18Ocarb and Δ47) were determined on pure dolomite samples that had been chemically isolated, and the results interpreted using a coupled numerical model. This analysis strongly suggests that the dolomite was replaced by Cambrian seawater (ca −2‰) and subsequently experienced closed‐system recrystallization (water/rock ratio <0.4) in the deep burial stage. The vertical variation of the mol% Mg content of the dolomite shows multiple episodes of dolomitization with the increasing stoichiometry in each episode suggesting the control of sea‐level changes. This study has revealed that the normal‐seawater dolomitization could also proceed in an evaporative environment on a shallow‐water platform. As in many studies of ancient carbonates, the recognition of diagenetic fluids is often hindered by complex geochemical overprinting in bulk samples. [ABSTRACT FROM AUTHOR]

Sea water is abundant in lithium reserves, and extracting lithium metal from it holds the potential to not only mitigate the shortage of lithium in light of the fast‐growing electric vehicle industry, but also serve as an anode electrode to provide electricity. The task, however, is challenging due to the harsh reactions and low lithium concentration in sea water. Here, we present a single‐channel strategy based on a flexible and scalable lithium ion‐sieve membrane for efficient lithium extraction. Our composite membrane exhibits high separation factor βLi/Na of more than 2.87×107 with an ionic conductivity of 6.2×10−5 S cm−1. Lithium metal was electrolytically extracted from sea water through a hybrid‐electrolyte system, which yielded a high Coulombic efficiency of 98.04 % and a low energy consumption of 17.4 kWh kgLi−1 at an optimized extracting current of 200 μA cm−2. The extracted lithium metal can be directly integrated into a lithium‐sulfur battery, delivering an energy output of 395 Wh kg−1. To demonstrate its industrial viability, we also fabricate a pouch cell with Li metal anode extracted by an amplified extraction prototype. This study has the potential to dispel concerns of lithium depletion and facilitate the sustainable development of lithium‐based energy storage systems. [ABSTRACT FROM AUTHOR]

Seawater corrosion poses significant challenges to marine industrial equipment, leading to a reduced lifespan and potential safety hazards. To enhance the corrosion resistance and reliability of titanium alloys in marine environments, a superhydrophobic TiO₂ nanotube-carbon fiber composite coating (SCF-TAD20) was developed through anodic oxidation, spraying, and chemical modification. SCF-TAD20 achieves a contact angle of 153°, which facilitates excellent corrosion protection due to its unique micro-nano structure, gas barrier properties, and chemical resistance. Electrochemical tests demonstrate that SCF-TAD20 increases the corrosion potential from −0.482 V to 0.0612 V and reduces the corrosion current density from 377.8 × 10−8 A/cm2 to 0.615 × 10−8 A/cm2, a four-order decrease. Its charge transfer resistance (∼8.81E6 Ω·cm2) is significantly higher than that of the substrate (∼3.03E5 Ω·cm2). The coating also performs well in seawater with varying pH levels, showing the lowest corrosion current density and a significant increase in resistive arc radius. This research presents a novel approach to enhancing TC4 titanium alloys for marine applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • A "ring-shaped cavity induced" strategy is proposed for abundant Pt/WO 3-x heterostructures. • Pt x P 8 W 48 POMs act as superior precursor to regulate Pt-O-W synergy at atomic level. • Pt/WO 3-x @rGO exhibits remarkable electrocatalytic activity and durability in acidic water and seawater. Developing novelplatinum (Pt)-based hydrogen evolution reaction (HER) catalysts with high activity and stability is significant for the ever-broader applications of hydrogen energy. However, achieving precise modulation of the ultrafine Pt nanoparticles coordination environment in conventional catalysts is challenging. In this work, we developed a unique "ring-shaped cavity induced" strategy to anchor the Pt x through the ring-shaped cavity of polyoxometalates (POMs) Na 33 H 7 P 8 W 48 O 184 (denoted as P 8 W 48). The Na y Pt x [P 8 W 48 O 184 ] (Pt x P 8 W 48) was in-situ converted into abundant Pt/WO 3-x heterostructure with Pt (∼2 nm) and highly depressed Pt-O-W heterointerfaces. Pt/WO 3-x nanoparticles supported on highly conductive rGO exhibit superior HER activity. The overpotentials of the catalyst are only 2.8 mV and 4.7 mV at 10 mA·cm−2 in acidic water and seawater, far superior to commercial 20 % Pt/C catalyst. Additionally, the catalyst can be stabilized at a current density of 30 mA·cm−2 for 180 h. This study provides a feasible strategy for rational design of Pt-based catalysts for renewable energy applications. [ABSTRACT FROM AUTHOR]

Based on the mechanical regulation mechanism, a super‐low‐frequency (SLF) reconfigurable magnetoelectric (ME) antenna is proposed for underwater frequency‐hopping communication. By constructing the mechanical model of the ME antenna loaded with an adjustable spring, the antenna's working frequency is predicted to be tuned in an extensive dynamic range from 148 to 331 Hz by changing the states of a loaded spring. The experiment is implemented in the frequency‐response test platform and the practical communication system using the minimum shift keying modulation. The former experiment well validates the tunable frequency response of the reconfigurable ME antenna, while the latter successfully achieves the information transmission at different working frequencies. The proposed SLF reconfigurable ME antenna serves as a potential candidate for under‐water frequency‐hopping communication. [ABSTRACT FROM AUTHOR]

Current marine research that leverages remote sensing data urgently requires gridded data of high spatial and temporal resolution. However, such high-quality data is often lacking due to the inherent physical and technical constraints of sensors. A necessary trade-off therefore exists between spatial, temporal, and spectral resolution in satellite remote sensing technology: increasing spatial resolution often reduces the coverage area, thereby diminishing temporal resolution. This manuscript introduces an innovative remote sensing image fusion algorithm that combines Sentinel-2 (high spatial resolution) and Sentinel-3 (relatively high spectral and temporal resolution) satellite data. The algorithm, based on a cross-attention mechanism and referred to as the Cross-Attention Spatio-Temporal Spectral Fusion (CASTSF) model, accounts for variations in spectral channels, spatial resolution, and temporal phase among different sensor images. The proposed method enables the fusion of atmospherically corrected ocean remote sensing reflectance products (Level 2 OSR), yielding high-resolution spatial data at 10 m resolution with a temporal frequency of 1–2 days. Subsequently, the algorithm generates chlorophyll-a concentration remote sensing products characterized by enhanced spatial and temporal fidelity. A comparative analysis against existing chlorophyll-a concentration products demonstrates the robustness and effectiveness of the proposed approach, highlighting its potential for advancing remote sensing applications. [ABSTRACT FROM AUTHOR]