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Estuarine wetlands harbor considerable carbon stocks, but rising sea levels could affect their ability to sequester soil carbon as well as their potential to emit methane (CH4). While sulfate loading from seawater intrusion may reduce CH4 production due to the higher energy yield of microbial sulfate reduction, existing studies suggest other factors are likely at play. Our study of 11 wetland complexes spanning a natural salinity and productivity gradient across the San Francisco Bay and Delta found that while CH4 fluxes generally declined with salinity, they were highest in oligohaline wetlands (ca. 3-ppt salinity). Methanogens and methanogenesis genes were weakly correlated with CH4 fluxes but alone did not explain the highest rates observed. Taxonomic and functional gene data suggested that other microbial guilds that influence carbon and nitrogen cycling need to be accounted for to better predict CH4 fluxes at landscape scales. Higher methane production occurring near the freshwater boundary with slight salinization (and sulfate incursion) might result from increased sulfate-reducing fermenter and syntrophic populations, which can produce substrates used by methanogens. Moreover, higher salinities can solubilize ionically bound ammonium abundant in the lower salinity wetland soils examined here, which could inhibit methanotrophs and potentially contribute to greater CH4 fluxes observed in oligohaline sediments.IMPORTANCELow-level salinity intrusion could increase CH4 flux in tidal freshwater wetlands, while higher levels of salinization might instead decrease CH4 fluxes. High CH4 emissions in oligohaline sites are concerning because seawater intrusion will cause tidal freshwater wetlands to become oligohaline. Methanogenesis genes alone did not account for landscape patterns of CH4 fluxes, suggesting mechanisms altering methanogenesis, methanotrophy, nitrogen cycling, and ammonium release, and increasing decomposition and syntrophic bacterial populations could contribute to increases in net CH4 flux at oligohaline salinities. Improved understanding of these influences on net CH4 emissions could improve restoration efforts and accounting of carbon sequestration in estuarine wetlands. More pristine reference sites may have older and more abundant organic matter with higher carbon:nitrogen compared to wetlands impacted by agricultural activity and may present different interactions between salinity and CH4. This distinction might be critical for modeling efforts to scale up biogeochemical process interactions in estuarine wetlands.

Seawater intrusion into freshwater wetlands causes changes in microbial communities and biogeochemistry, but the exact mechanisms driving these changes remain unclear. Here we use a manipulative laboratory microcosm experiment, combined with DNA sequencing and biogeochemical measurements, to tease apart the effects of sulfate from other seawater ions. We examined changes in microbial taxonomy and function as well as emissions of carbon dioxide, methane, and nitrous oxide in response to changes in ion concentrations. Greenhouse gas emissions and microbial richness and composition were altered by artificial seawater regardless of whether sulfate was present, whereas sulfate alone did not alter emissions or communities. Surprisingly, addition of sulfate alone did not lead to increases in the abundance of sulfate reducing bacteria or sulfur cycling genes. Similarly, genes involved in carbon, nitrogen, and phosphorus cycling responded more strongly to artificial seawater than to sulfate. These results suggest that other ions present in seawater, not sulfate, drive ecological and biogeochemical responses to seawater intrusion and may be drivers of increased methane emissions in soils that received artificial seawater addition. A better understanding of how the different components of salt water alter microbial community composition and function is necessary to forecast the consequences of coastal wetland salinization.

Coastal wetlands are vulnerable to sea level rise with unknown consequences for mercury (Hg) cycling, particularly the potential for exacerbating neurotoxic methylmercury (MeHg) production and bioaccumulation in food webs. Here, the effect of sea level rise on MeHg formation in the Florida Everglades was evaluated by incubating peat cores from a freshwater wetland for 0-20 days in the laboratory at five salinity conditions (0.16-6.0 parts-per-thousand; 0.20-454 mg L-1 sulfate (SO42-)) to simulate the onset of sea level rise within coastal margins. Isotopically enriched inorganic mercury (201Hg(II)) was used to track MeHg formation and peat-porewater partitioning. In all five salinity treatments, porewaters became anoxic within 1 day and became progressively enriched in dissolved organic matter (DOM) of greater aromatic composition over the 20 days compared to ambient conditions. In the four highest salinity treatments, SO42- concentrations decreased and sulfide concentrations increased over time due to microbial dissimilatory SO42- reduction that was concurrent with 201Hg(II) methylation. Importantly, elevated salinity resulted in a greater proportion of produced Me201Hg observed in porewaters as opposed to bound to peat, interpreted to be due to the complexation of MeHg with aromatic DOM released from peat. The findings highlight the potential for enhanced production and mobilization of MeHg in coastal wetlands of the Florida Everglades due to the onset of saltwater intrusion.

Pyrite is one of the most abundant metal sulfide tailings and is susceptible to oxidation, yielding acidic mine drainage (AMD) that poses significant environmental risks. Consequently, the exploration of pyrite surface oxidation and the kinetic influencing factors remains a pivotal research area. Despite the oxidation of pyrite producing a significant amount of sulfate (SO42−), a comprehensive investigation into its influence on the oxidation process is lacking. Leveraging pyrite's semiconducting nature and the electrochemical intricacies of its surface oxidation, this study employs electrochemical techniques—cyclic voltammetry (CV), Tafel polarization, and electrochemical impedance spectroscopy (EIS)—to assess the effect of SO42⁻ on pyrite surface oxidation. The CV curve shows that SO42− does not change the fundamental surface oxidation mechanism of pyrite, but its redox peak current density decreases with the increase in SO42−, and the surface oxidation rate of pyrite decreases. The possible reason is attributed to SO42− adsorption onto pyrite surfaces, blocking active sites and impeding the oxidation process. Furthermore, Tafel polarization curves indicate an augmentation in polarization resistance with elevated SO42− concentrations, signifying heightened difficulty in pyrite surface reactions. EIS analysis underscores an increase in Weber diffusion resistance with increasing SO42⁻, indicating that the diffusion of Fe3+ to the pyrite surface and the diffusion of oxidized products to the solution becomes more difficult. These findings will improve our understanding of the influence of SO42− on pyrite oxidation and have important implications for deepening the understanding of surface oxidation of pyrite in the natural environment. [ABSTRACT FROM AUTHOR]

Leaf litter in coastal wetlands lays the foundation for carbon storage, and the creation of coastal wetland soils. As climate change alters the biogeochemical conditions and macrophyte composition of coastal wetlands, a better understanding of the interactions between microbial communities, changing chemistry, and leaf litter is required to understand the dynamics of coastal litter breakdown in changing wetlands. Coastal wetlands are dynamic systems with shifting biogeochemical conditions, with both tidal and seasonal redox fluctuations, and marine subsidies to inland habitats. Here, we investigated gene expression associated with various microbial redox pathways to understand how changing conditions are affecting the benthic microbial communities responsible for litter breakdown in coastal wetlands. We performed a reciprocal transplant of leaf litter from four distinct plant species along freshwater‐to‐marine gradients in the Florida Coastal Everglades, tracking changes in environmental and litter biogeochemistry, as well as benthic microbial gene expression associated with varying redox conditions, carbon degradation, and phosphorus acquisition. Early litter breakdown varied primarily by species, with highest breakdown in coastal species, regardless of the site they were at during breakdown, while microbial gene expression showed a strong seasonal relationship between sulfate cycling and salinity, and was not correlated with breakdown rates. The effect of salinity is likely a combination of direct effects, and indirect effects from associated marine subsidies. We found a positive correlation between sulfate uptake and salinity during January with higher freshwater inputs to coastal areas. However, we found a peak of dissimilatory sulfate reduction at intermediate salinity during April when freshwater inputs to coastal sites are lower. The combination of these two results suggests that sulfate acquisition is limiting to microbes when freshwater inputs are high, but that when marine influence increases and sulfate becomes more available, dissimilatory sulfate reduction becomes a key microbial process. As marine influence in coastal wetlands increases with climate change, our study suggests that sulfate dynamics will become increasingly important to microbial communities colonizing decomposing leaf litter. [ABSTRACT FROM AUTHOR]

As a part of efforts to develop a laboratory soil-resin incubation technique to assess soil phosphorus (P) release by mixing resin beads directly with soil acting as a P sink to mimic plant root uptake, selecting a suitable type of anion exchange resin (AER) is essential. Thus, five types of strong basic AER in bicarbonate (HCO3)—form were evaluated for their ion exchange characteristics in salt solutions. The P adsorption study was conducted under four sulfate (SO42-) concentrations (0.1, 0.01, 0.001, and 0.0001 M) at each of three fixed concentrations (0.21, 0.62, and 2.06 mM) of potassium dihydrogen phosphate (K2HPO4). Results showed that adsorbed P was quantitatively extracted from the resins with dilute hydrochloric acid (1 M, HCl). Also, increasing the SO42- concentration dramatically decreased the adsorption of P by the resins, with little difference between a one- and seven-day equilibration period. All five resins behaved similarly at higher concentrations of SO42-, but at lower concentrations of SO42-, the HCO3—form Amberlite I-6766 resin had a higher affinity for P than other Dowex resins. There was much greater P adsorption to the resin at solution pH > 7.2, which suggests hydrogen phosphate (HPO42-) to be much more strongly adsorbed than dihydrogen phosphate (H2PO4−). Also, the Amberlite resin has more favorable physical properties with a granular structure, lower density, and ease of handling and separation from soil, which was chosen for subsequent soil studies. [ABSTRACT FROM AUTHOR]

China is the largest producer and user of Ordinary Silicate Cement (OPC), and rapid infrastructure development requires more sustainable building materials for concrete structures. Portland cement emits large amounts of CO2 in production. Given proposals for "carbon peaking and carbon neutralization", it is extremely important to study alternative low-carbon cementitious materials to reduce emissions. Alkali-activated slag (AAS) cement, a new green cementitious material, has high application potential. The chemical corrosion resistance of AAS concrete is important for ensuring durability and prolonging service life. This paper reviews the hydration mechanism of AAS concrete and discusses the composition of hydration products on this basis, examines the corrosion mechanism of AAS concrete in acid, sulfate, and seawater environments, and reviews the impact of its performance due to the corrosion of AAS concrete in different solutions. Further in-depth understanding of its impact on the performance of concrete can provide an important theoretical basis for its use in different environments and provides an important theoretical basis for the application of AAS concrete, so that we can have a certain understanding of the durability of AAS concrete. [ABSTRACT FROM AUTHOR]

AbstractThe degradation of cement-stabilized soil foundations in coastal environments is primarily caused by the corrosive effects of chloride and sulfate ions. While Nano-SiO2 enhances the mechanical properties of cemented soil, it may also increase brittleness, affecting safety and cost-effectiveness. Polypropylene fibers improve ductility by inhibiting crack propagation but contribute minimally to strength enhancement. To optimize performance, this study employed 3.6% Nano-SiO2 and 0.8% polypropylene fibers. Unconfined compressive strength (UCS) tests indicate that with increasing curing time, erosion from Cl− and SO42− significantly increases the brittleness of Nano-modified cemented soil, with compressive strength initially rising and then declining. The incorporation of polypropylene fibers further enhances both compressive strength and deformation modulus. At 60 days of curing, the composite cemented soil exhibits strength improvements greater than the sum of the individual gains in various environments, with compressive strength increases of 248.9, 159.9, and 102.9% in freshwater, chloride, and sulfate conditions, respectively. Scanning electron microscopy and X-ray diffraction analyses indicate that excessive expansion products from Cl− and SO42− reduce Nano-SiO2’s effectiveness. The C-S-H gel fills the indentations on the fiber surface and tightly envelops it, while Nano-SiO2 further enhances the mechanical interlocking between the fibers and the matrix, thereby improving durability in marine. [ABSTRACT FROM AUTHOR]

Small bifunctional molecules are attractive for use as models in different areas of knowledge. How can their functional groups interact in solids? This is important to know for the prediction of the physical and chemical properties of the materials based on them. In this study, two new hydrogen-bonded organic frameworks (HOFs) based on sterically demanding molecular compounds, bis(1-hydroxy-2-methylpropane-2-aminium) sulfate (1) and 2-methyl-4-oxopentan-2-aminium hydrogen ethanedioate hydrate (2), were synthesized and fully characterized by means of FTIR and NMR spectroscopies, as well as by X-ray powder diffraction and thermogravimetric analyses. Their molecular and crystal structures were established through single-crystal X-ray diffraction analysis. It was shown that both compounds have a layered structure due to the formation of a 2D hydrogen-bonding network, the layers being linked by systematically arranged Van der Waals contacts between the methyl groups of organic cations. To unveil some dependencies between the chemical nature of bifunctional molecules and their solid structure, Hirschfeld surface (HS) analysis was carried out for HOFs 1, 2, and their known congeners 1-hydroxy-2-methylpropan-2-aminium hemicarbonate (3) and 1-hydroxy-2-methylpropan-2-aminium (1-hydroxy-2-methylpropan-2-yl) carbamate (4). HS was performed to quantify and visualize the close intermolecular atomic contacts in the crystal structures. It is clearly seen that H–H contacts make the highest contributions to the amino alcohol based compounds 1, 3 and 4, with a maximal value of 65.2% for compound 3 having CO32− as a counterion. A slightly lower contribution of H–H contacts (64.4%) was found for compound 4, in which the anionic part is represented by 1-hydroxy-2-methylpropan-2-yl carbamate. The significant contribution of the H–H contacts in the bifunctional moieties is due to the presence of a quaternary carbon atom with a short three-carbon chain. [ABSTRACT FROM AUTHOR]

Single crystal of a thallium‐containing sulfate Tl2Pb(SO4)2 was prepared through hydrothermal crystallization starting from Tl2CO3, Pb(NO3)2 and H2SO4. The crystal structure was solved from single‐crystal X‐ray diffraction data: Tl2Pb(SO4)2 crystallizes in space group R3‾ ${\bar{3}}$ m with lattice parameters of a=5.5955(2) Å, c=22.1001(9) Å, and Z=3, which is also corroborated by Rietveld refinement on X‐ray powder data. The crystal structure can be regarded as [Pb(SO4)2]2− sheets intercalated by double layers of Tl+ along the c‐axis. From a mineralogical perspective, Tl2Pb(SO4)2 belongs to the palmierite family and can further be classified within palmierite‐supergroup. Validation of the structure models was carried out utilizing various concepts including Bond Valence (BV), Charge Distribution (CD) and Madelung Part of Lattice Energy (MAPLE). Notably, a contrast in stereochemical activity of 6s2 lone electron pair (LEP) between Tl+ and Pb2+ is interpreted in terms of bonding behaviours as well as Wang‐Liebau Eccentricity (WLE) parameters. Moreover, an extensive investigation into the crystal chemistry of thallium‐containing sulfates was conducted for the first time, focusing on the coordination environment and bonding behaviour of Tl+ and corresponding WLE parameters. A comparative analysis of these structurally related compounds including Tl2Pb(SO4)2, Tl3H(SO4)2, TlBi(SO4)2, TlIn(SO4)2, TlRh(SO4)2, and TlAl(SO4)2 was delineated. [ABSTRACT FROM AUTHOR]

Acid mine drainage (AMD) is an environmental concern, and its discharge into the surrounding environment can lead to acidification of water bodies and soil. In this research, red mud (RM) with alkaline pH as aluminum industry waste was implemented as an adsorbent for sulfate removal, which can be available in AMD and adsorption processes as an influential method was applied for AMD treating. Seawater washing (BRM), acid treatment (HRM), and composition with chitosan (CRM) were employed as RM modification methods. Various analytical methods were applied, including x-ray fluorescence spectroscopy (XRF), Fourier-transform infrared spectroscopy (FTIR), Brunauer Emmett Teller (BET), inductively coupled plasma analysis, and zeta potential, to have a clear comprehension of the sulfate adsorption behaviors and performance of activated methods. These methods have had desirable effects on the sulfate adsorption and adsorption amount, which range from 1.1 mg g−1 for RM reached to 13.4, 39.7, and 67.4 mg g−1 for BRM, HRM, and CRM, respectively. XRF results demonstrated a decrease in calcium and sodium ion amounts that can occur due to their dissolution in the acidic solution. It can create the active surface areas for adsorption onto RM with acid washing. Based on FTIR results, sharp intensity vibration was observed in BRM, HRM, and CRM after sulfate adsorption in the 1,100 cm−1 band that is approximately related to SO42− vibration. BRM porosity decreased from 0.0686 to 0.0345 cm3 g−1 due to various salts' precipitation in seawater, but the porosity volume and specific surface area increased for HRM from 0.0686 to 0.184 cm3 g−1 due to dissolution of ions in HCl. In addition, zeta potential increased to positive amounts from 2.7 to 3.4, 3.8, and 4.5 mv for BRM, HRM, and CRM, respectively. Langmuir isotherm indicated that the highest adsorption amount (qm) as a calculated parameter for BRM, HRM, and CRM was 0.88, 2.45, and 18.6 mg g−1 , respectively. Among modification methods, combination RM and chitosan had the highest impact and increases sulfate removal and adsorption amount at lower pH levels due to further positive charge on the CRM surface. [ABSTRACT FROM AUTHOR]

The emergence of a crystal nucleus from disordered states is a critical and challenging aspect of the crystallization process, primarily due to the extremely short length and timescales involved. Methods such as liquid-cell or low-dose focal-series transmission electron microscopy (TEM) are often employed to probe these events. In this study, we demonstrate that ion mobility spectrometry-mass spectrometry (IMS-MS) offers a complementary and insightful perspective on the nucleation process by examining the sizes and shapes of small clusters, specifically those ranging from n = 2 to 40. Our findings reveal the significant role of sulfate ions in the growth of adeninediium sulfate clusters, which are the precursors to the formation of single crystals. Specifically, sulfate ions stabilize adenine clusters at the 1:1 ratio. In contrast, guanine sulfate forms smaller clusters with varied ratios, which become stable as they approach the 1:2 ratio. The nucleation size is predicted to be between n = 8 and 14, correlating well with the unit cell dimensions of adenine crystals. This correlation suggests that IMS-MS can identify critical nucleation sizes and provide valuable structural information consistent with established crystallographic data. We also discuss the strengths and limitations of IMS-MS in this context. IMS-MS offers rapid and robust experimental protocols, making it a valuable tool for studying the effects of various additives on the assembly of small molecules. Additionally, it aids in elucidating nucleation processes and the growth of different crystal polymorphs. [ABSTRACT FROM AUTHOR]

Root-based uptake of inorganic carbon has been suggested as an additional carbon source. Our study aimed to characterize and understand the root-based uptake and fixation mechanisms and their impact on plant growth. 13C-labeled bicarbonate fed to Arabidopsis roots was assimilated into aspartic acid but mainly into sucrose, indicating that the added inorganic carbon was transported to the leaves. A hydroponic treatment was also established for A. thaliana using 2 mM NaHCO3 at pH 5.6, which enhanced the photosynthetic and growth parameters. According to transcriptome sequencing data, the observed enhancement in growth may be orchestrated by trehalose-6-phosphate signaling and supported by augmented nitrogen and sulfur assimilation. The analysis also revealed regulatory and transporter activities, including several nitrate (NRT2.1), and sulfate transporter (SULTR1;1 and SULTR1;2) candidates that could participate in bicarbonate uptake. Different transporters and carbon fixation mutants were assessed. Arabidopsis homologs of SLOW-TYPE ANION CHANNEL 1 (slah3) CARBONIC ANHYDRASE (bca4), and SULFATE TRANSPORTER (sultr1;2) mutants were shown to be inferior to the bicarbonate-treated wild types in several growth and root ultrastructural parameters. Besides, aquaporin genes PIP1;3 and PIP2;6 could play a negative role in the carbon uptake by venting carbon dioxide out of the plant. The findings support the hypothesis that the inorganic carbon is taken up by the root anion channels, mostly transported up to the shoots by the xylem, and fixed there by RuBisCo after the conversion to CO2 by carbonic anhydrases. The process boosts photosynthesis and growth by providing an extra carbon supply. [ABSTRACT FROM AUTHOR]

Fine particulate matter (PM 2.5) has been implicated in various health concerns. However, a comprehensive understanding of the specific PM 2.5 components affecting depression remains limited. This study conducted a Cox proportional-hazards model to assess the effect of PM 2.5 components on the incidence of depression based on the China Health and Retirement Longitudinal Study (CHARLS). Participants with 10-item Center for Epidemiologic Studies Depression Scale (CESD-10) score of 10 or higher were classified as exhibiting depression. Our findings demonstrated a significant positive correlation between long-term exposure to black carbon (BC), sulfate (SO 4 2−), and organic matter (OM) components of PM 2.5 and the prevalence of depression. Per 1 Interquartile Range (IQR) increment in 3-year average concentrations of BC, OM, and SO 4 2− were associated with the hazard ratio (HR) of 1.54 (95 % confidence intervals (CI): 1.44, 1.64), 1.24 (95% CI : 1.16, 1.34) and 1.25 (95% CI : 1.16, 1.35). Notably, females, younger individuals, those with lower educational levels, urban residents, individuals who were single, widowed, or divorced, and those living in multi-story houses exhibited heightened vulnerability to the adverse effects of PM 2.5 components on depression. Firstly, pollutant data is confined to subjects' fixed addresses, overlooking travel and international residence history. Secondly, the analysis only incorporates five fine particulate components, leaving room for further investigation into the remaining fine particulate components in future studies. This study provides robust evidence supporting the detrimental impact of PM 2.5 components on depression. The identification of specific vulnerable populations contributes to a deeper understanding of the underlying mechanisms involved in the relationship between PM 2.5 components and depression. • This study explore the association between PM 2.5 components and depression. • Black carbon, sulfate, and organic matter have significant impacts on depression. • Females, who living in multi-story house were susceptible to the PM 2.5 components. [ABSTRACT FROM AUTHOR]

In traditional sulfate electroforming copper without additives, the electroformed deposit often exhibits defects such as pinholes, burrs and nodules. The mechanical properties of copper electroforming deposits can be improved through an abrasive-assisted electroforming process at high current density. However, excessive dissolution of copper anodes often results in the generation of a significant amount of copper ions, which subsequently turn into copper powder by disproportionation reaction, leading to the formation of burrs on the surface of cathode. In this paper, the anode area is increased to reduce the anode current density and enhance the electric field. This can improve electric field and decrease Cu+ or copper powder in the solution. The experimental results show that the mechanical properties of the electroformed deposit with bilateral anodes are significantly improved. The electroformed copper deposit with a microhardness value of 138.4 HV, a tensile strength of 259.2 Mpa and an elongation of 13.6% can be obtained, which is increased by 8.5, 27.2 and 1.7%, respectively, compared with the one-sided placement. [ABSTRACT FROM AUTHOR]

Al3+-toxicity in acidic soils is among the main abiotic stress factors that generate adverse effects in plant growth; in leaves, it affects several physiological parameters such as photosynthesis and ROS balance, leading to limited crop production. On the other hand, sulfur is a macronutrient that has a key role against oxidative stress and improves plant growth in acidic soils; however, the implication of sulfate nutritional status in the modulation of short-term Al3+-toxicity tolerance mechanisms in plant leaves are barely reported. This study is focused on the role of sulfate on the leaf response of an Al3-sensitive perennial ryegrass (Lolium perenne cv. Jumbo) after 48 h of exposure. Lolium perenne cv. Jumbo seeds were cultivated in hydroponic conditions with modified Taylor Foy solutions supplemented with 120, 240, and 360 μM sulfate in the presence or absence of Al3+-toxicity. The L. perenne cv. Jumbo leaves were collected after 48 h of Al3+-toxicity exposure and processed to evaluate the effects of sulfate on Al3+ toxicity, measuring total proteins, mineral uptake, photosynthesis modulation, and ROS defense mechanism activation. The plants exposed to Al3+-toxicity and cultivated with a 240 µM sulfate amendment showed a recovery of total proteins and Ca2+ and Mg2+ concentration levels and a reduction in TBARS, along with no changes in the chlorophyll A/B ratio, gene expression of proteins related to photosynthesis (Rubisco, ChlAbp, and Fered), or ROS defense mechanism (SOD, APX, GR, and CAT) as compared with their respective controls and the other sulfate conditions (120 and 360 µM). The present study demonstrates that adequate sulfate amendments have a key role in regulating the physiological response against the stress caused by Al3+ toxicity. [ABSTRACT FROM AUTHOR]

The corrosion of pre-passivated Cr10Mo1 steels in simulated concrete pore solution of saturated Ca(OH)2 induced by different corrosive ions were investigated, namely Cl−, SO2- 4, and combination of Cl− and SO2- 4. Electrochemical methods, Pourbaix analysis of Fe–Cr–H2O system and DFT calculation were adopted to characterize corrosion behavior and reveal underlying mechanism. Results showed that while sulfate may induce corrosion at higher threshold value, the scenario of chloride alone leads to lowest corrosion potential, linear polarization resistance and highest corrosion rate, and the presence of SO2- 4 ions mitigate corrosion risk under the coexistence condition of chloride and sulfate. A two-step reaction model of competitive adsorption-catalytic corrosion was proposed based on theoretical analysis and DFT calculation results.

Abstract Groundwater is a vital source of water for human and agricultural use in many parts of the world. The purpose of this research was to establish the quality of groundwater in Riyadh, Saudi Arabia, as well as the human health concerns associated with it. We collected and examined groundwater samples for pH, EC, TDS, CaCO3, fluoride (F−), chloride (Cl−), sulfate (SO4 2−), and nitrate (NO3 −). The ion chromatography conductometric detection method was constructed to determine fluoride, chloride, sulfate, and nitrate in groundwater. The suggested method worked well for the anions that were being studied; it had a high coefficient of determination (r2 > 0.998) and average recoveries for all analytes that were between 97.5% and 99.0%, with a range of error of 0.77 to 2.37%. Fluoride concentrations were detected between 0.001 and 0.14 mg/L, which are within the acceptable limit by several organizations. Chloride was measured in the range of 17.1 to 966.5 mg/L, with some samples above the limits. The influence on sulfate ranged from 2.0 to 1136.0 mg/L, with several samples exceeding the limits. In contrast, with nitrate levels ranging from 1.4 to 5.0 mg/L, the majority of the samples fall within the acceptable range. The overall intake of fluoride, chloride, sulfate, and nitrate is 0.00605, 138.911, 65.515, and 1.19, respectively, which is lower than the recommended daily consumption except for chloride. The groundwater sample contains fluoride and nitrate with HQ values less than one: 0.000064–0.0641 and 0.033654–0.120192. Humans in Riyadh, Saudi Arabia, do not pose a health risk when digesting or absorbing groundwater fluoride or nitrate.

Marine phytoplankton are primary producers in ocean ecosystems and emit dimethyl sulfide (DMS) into the atmosphere. DMS emissions are the largest biological source of atmospheric sulfur and are one of the largest uncertainties in global climate modeling. DMS is oxidized to methanesulfonic acid (MSA), sulfur dioxide, and hydroperoxymethyl thioformate, all of which can be oxidized to sulfate. Ice core records of MSA are used to investigate past DMS emissions but rely on the implicit assumption that the relative yield of oxidation products from DMS remains constant. However, this assumption is uncertain because there are no long-term records that compare MSA to other DMS oxidation products. Here, we share the first long-term record of both MSA and DMS-derived biogenic sulfate concentration in Greenland ice core samples from 1200 to 2006 CE. While MSA declines on average by 0.2 µg S kg-1 over the industrial era, biogenic sulfate from DMS increases by 0.8 µg S kg-1. This increasing biogenic sulfate contradicts previous assertions of declining North Atlantic primary productivity inferred from decreasing MSA concentrations in Greenland ice cores over the industrial era. The changing ratio of MSA to biogenic sulfate suggests that trends in MSA could be caused by time-varying atmospheric chemistry and that MSA concentrations alone should not be used to infer past primary productivity.

[Display omitted] • Fe-Ni 2 P-SO 4 2−/carbon was synthesized via sulfate salt assistant strategy. • This strategy can incorporate SO 4 2− into phosphide nanofibers. • The incorporation of SO 4 2− can optimize the adsorption strength of intermediates. • The electrocatalyst requires a low overpotential of 357 mV at 1000 mA cm−2. The incorporation of oxyanion groups offers a greater potential for enhancing the activity of oxygen evolution reaction (OER) electrocatalysts compared to traditional metal cations doping, owing to their unique configurations and high electronegativity. However, the incorporation of oxyanion groups that differ from those derived from the oxidation of anions in transition metal monoxides poses significant challenges, thereby limiting further applications of oxyanion group modification approach. Herein, we present a novel sulfate salt assistant approach to fabricate Fe-doped Ni 2 P modified with SO 4 2−/carbon (Fe-Ni 2 P-S/C) nanofibers as highly efficient OER electrocatalyst. The optimized Fe-Ni 2 P-S/C nanofibers display superb OER activity, requiring low overpotentials of 266, 323, and 357 mV at 100, 500, and 1000 mA cm−2, respectively. Theoretical calculations reveal that the co-adsorption of PO 4 3− and SO 4 2− on the surface of reconstructed electrocatalyst can reduce the energy barrier of rate-determining step, thereby resulting in enhanced OER activity. The present study emphasizes the crucial role played by anion groups in OER activity as well as proposes a novel approach for incorporating anion groups into electrocatalysts. [ABSTRACT FROM AUTHOR]

In recent years, "sulfate-free" products have become increasingly common for most cosmetics and personal care products. With a boom in the number of sulfate-free claims, an analytical method for determining sulfate is certainly needed. Analysis of sulfate in cosmetic products can be difficult due to matrix interference and the complex nature of the ingredients used in the formulation. A simple and novel modified method for the determination of sulfate was developed by using UV–Vis spectroscopy. The procedure involved the precipitation of sulfate as barium sulfate and the removal of interference under controlled conditions, using different reagents such as acid, glycerol and ethanol. The method was optimized for the best conditions using response surface methodology. According to the experimental design, nitric acid and glycerol at 2% concentration yielded the maximum absorbance and the optimized method was validated in terms of linearity, accuracy, precision, limit of detection and limit of quantification. Fifteen market samples belonging to the shampoo and conditioner product types were analyzed to evaluate the performance of the optimized method. The results obtained were found to be satisfactory, and the proposed method is linear (R2—0.9971), accurate (89 to 92%), precise (%RSD < 4) and robust (% deviation < 5) with limit of detection (4.2 mg/l), limit of quantification (12.59 mg/l) and can be employed for the analysis of sulfate in cosmetics and personal care products. [ABSTRACT FROM AUTHOR]

This study provided insight into the origin, age, and formation conditions of the Late Oligocene sulfate lithofacies that were deposited in the SW Erzincan Basin throughout a broad region. Primary, secondary gypsum, and anhydrite make up the majority of sulfates, which are interbedded with clastic, volcanic, volcaniclastic and carbonated rocks. During the early-late diagenetic processes, primary gypsum changes into secondary gypsum along with primary anhydrite that is growing within the host-sediment. In the lithofacies, sedimentary structures created by tectonism and diagenesis are commonly found. The distribution of element concentrations shows that continental detrital input has a significant impact. Fe- and Mg-rich clays imply alkaline and hot-humid environmental conditions in the basin. The negative trend relationship of CaO with MgO refers to carbonation in the environment, while Sr, Ba, U, Mo, Ni, Cu and Zn values and Co, Ni/Co (0.98), Co/Zn (11.3), Cu/Zn (1.39) ratios and the high positive correlation of Cu with Al2O3 (r = +0.72) indicate the dominance of biologic factor, high salinity and reducing conditions in sulfates. The presence and values of Fe–Mn-rich alteration zones detected by field, mineralogical and geochemical studies within the gypsum revealed the hydrothermal solution activity in the region. 87Sr/86Sr, 18O/16O, 34S/32S and δ13C isotope data are consistent with Late Oligocene marine sulfates and suggest occasional mixing of freshwater. In addition, the origin and age data revealed by this study; It contributed to the paleogeographic evolution of the northern branch of Neotethys (Inner Tauride Ocean), which extends along the Central and northern-central Anatolia and Eastern Anatolia basins line, which includes Paleogene evaporitic deposits in Turkey, where the study area is located. Accordingly, it is obvious that the Neotethys, which extends along the basins from west to east, is quite shallow (lagoonal and coastal sabkha, etc.) and started to close further east during the Middle-Late Miocene (Erzurum-Pasinler- Horasan, Erzurum-Hınıs-Tekman, Iğdır-Tuzluca lacustrine basins, etc.). [ABSTRACT FROM AUTHOR]

Abstract Background There is increasing evidence that exposure to PM2.5 and its constituents is associated with an increased risk of gestational diabetes mellitus (GDM), but studies on the relationship between exposure to PM2.5 constituents and the risk of GDM are still limited. Methods A total of 17,855 pregnant women in Guangzhou were recruited for this retrospective cohort study, and the time-varying average concentration method was used to estimate individual exposure to PM2.5 and its constituents during pregnancy. Logistic regression was used to assess the relationship between exposure to PM2.5 and its constituents and the risk of GDM, and the expected inflection point between exposure to PM2.5 and its constituents and the risk of GDM was estimated using logistic regression combined with restricted cubic spline curves. Stratified analyses and interaction tests were performed. Results After adjustment for confounders, exposure to PM2.5 and its constituents (NO3 −, NH4 +, and OM) was positively associated with the risk of GDM during pregnancy, especially when exposure to NO3 − and NH4 + occurred in the first to second trimester, with each interquartile range increase the risk of GDM by 20.2% (95% CI: 1.118–1.293) and 18.2% (95% CI. 1.107–1.263), respectively. The lowest inflection points between PM2.5, SO4 2−, NO3 −, NH4 +, OM, and BC concentrations and GDM risk throughout the gestation period were 18.96, 5.80, 3.22, 2.67, 4.77 and 0.97 µg/m3, respectively. In the first trimester, an age interaction effect between exposure to SO4 2−, OM, and BC and the risk of GDM was observed. Conclusions This study demonstrates a positive association between exposure to PM2.5 and its constituents and the risk of GDM. Specifically, exposure to NO3 −, NH4 +, and OM was particularly associated with an increased risk of GDM. The present study contributes to a better understanding of the effects of exposure to PM2.5 and its constituents on the risk of GDM.

CaCO3 has long been used as a filler to increase many properties of the material. The filler commonly consists of inexpensive materials that replace some volume of the more expensive materials, which can reduce the cost of the final product. CaCO3 morphology that can be used as filler depends on the filler's function, such as filler for paper, paint, rubber, or composite. A filler for composite materials is needed to increase interfacing interactions between the particulate fillers and the matrix. So, the particulate in a broader shape will be the best choice to function for such filler. In this research, in an attempt to increase the interfacing interaction, CaCO3 morphology was modified in such a way through crystal lattice modification assisted by sulfate incorporation and vibration. SEM analysis was implemented, and showed that the research successfully produced novel morphology in branchy-like polymorphs. FTIR analysis also proved that the crystal lattice has been modified. The morphology in branchy-like polymorph is supposed to increase interfacing interaction between CaCO3 as the filler and the matrix. The methods are also supposed to be implemented as the research is scaled up to commercial scale.

This paper presents the application of the artificial neural network model (ANN) to predict the expansion of ground bottom ash mortar due to sodium sulfate. Portland cement type I was replaced by ground bottom ash at ratios of 0, 10, 20, 30, 40, 50 and 60 percent by weight of binder. The expansion of mortar which immersed in 5% sodium sulfate at various ages was measured. To show the efficiency of the proposed model, the prediction results of the ANN model are compared with the multiple linear regression (MLR) and the multiple second order polynomial regression (MSPR) models through statistical values. From the prediction results, it was found that the ANN model has a very high expansion prediction accuracy and more effective than the MLR and MSPR. The ANN model has a statistical value of absolute variance higher than 0.99. Therefore, it is concluded that the ANN model has a strong prediction capability of expansion due to sulfate of ground bottom ash mortar.

The increasing mining activities have led to the problem of acid mine drainage (AMD) pollution. A method that combines biochar treatment as an adsorbent with wetland sediment treatment as a source of sulfate-reducing bacteria is used to address AMD effectively. This research aimed to determine the ability of biochar in combination with wetland sediment treatment to reduce sulfate and heavy metal content in acid mine drainage wastewater. This research was conducted on a laboratory scale in an AMD wastewater treatment reactor with the following treatments of biochar mixed with wetland sediment. Observations included sulfate content, pH, and heavy metal content. Scanning electron microscope (SEM) analysis was also performed on the biochar. SEM observations revealed the presence of small, dense, and irregularly shaped pores on the surface of the biochar. The results on day 30 showed that biochar mixed with wetland sediment was able to reduce sulfate concentration by 74.19% and reduced Pb by 73.79%, compared with treatment sediment only to 64.81% sulfate concentration and reduced Pb by 53.85%, treatment biochar only had reduced sulfate of 46.90% and reduced Pb by 58.67% and control 1.79% sulfate concentration and reduced Pb by 1.87%.

Sulfate is an important anion in natural waters, and its excessive concentration can be harmful. Therefore, in this study, the efficiency of sulfate removal using nanoclay montmorillonite (adsorbent) from water was investigated by determining the effect of adsorbent concentration, pH, time, and temperature to determine the optimal conditions. The sulfate adsorption isotherms were also examined. The highest sulfate removal was achieved at a concentration of 1 g/l of nanoclay montmorillonite, resulting in 4.47 mg/g or 23% removal, at pH 3 with 2.87 mg/g or 27% removal, at a time of 90 minutes with 2.15 mg/g or 21% removal, and at a temperature of 25°C with 3.54 mg/g or 35% removal. Thermodynamic constants indicated that sulfate adsorption on the adsorbent surfaces is endothermic and spontaneous. The pseudo-second-order kinetic model provided a better fit to the time data, indicating chemical adsorption of sulfate. Among the isotherm equations, the Langmuir equation showed a better fit compared to Freundlich, indicating monolayer adsorption surfaces. Furthermore, the maximum adsorption capacity of nanoclay montmorillonite for sulfate (SO4˭-S) was found to be 9.7 mg/g. SEM-EDX analysis also revealed surface adsorption of sulfur and changes in the surface. Therefore, this nanoclay was effective in removing sulfate from water.

Background: There is increasing evidence that exposure to PM2.5 and its constituents is associated with an increased risk of gestational diabetes mellitus (GDM), but studies on the relationship between exposure to PM2.5 constituents and the risk of GDM are still limited. Methods: A total of 17,855 pregnant women in Guangzhou were recruited for this retrospective cohort study, and the time-varying average concentration method was used to estimate individual exposure to PM2.5 and its constituents during pregnancy. Logistic regression was used to assess the relationship between exposure to PM2.5 and its constituents and the risk of GDM, and the expected inflection point between exposure to PM2.5 and its constituents and the risk of GDM was estimated using logistic regression combined with restricted cubic spline curves. Stratified analyses and interaction tests were performed. Results: After adjustment for confounders, exposure to PM2.5 and its constituents (NO3−, NH4+, and OM) was positively associated with the risk of GDM during pregnancy, especially when exposure to NO3− and NH4+ occurred in the first to second trimester, with each interquartile range increase the risk of GDM by 20.2% (95% CI: 1.118–1.293) and 18.2% (95% CI. 1.107–1.263), respectively. The lowest inflection points between PM2.5, SO42−, NO3−, NH4+, OM, and BC concentrations and GDM risk throughout the gestation period were 18.96, 5.80, 3.22, 2.67, 4.77 and 0.97 µg/m3, respectively. In the first trimester, an age interaction effect between exposure to SO42−, OM, and BC and the risk of GDM was observed. Conclusions: This study demonstrates a positive association between exposure to PM2.5 and its constituents and the risk of GDM. Specifically, exposure to NO3−, NH4+, and OM was particularly associated with an increased risk of GDM. The present study contributes to a better understanding of the effects of exposure to PM2.5 and its constituents on the risk of GDM. [ABSTRACT FROM AUTHOR]

The release of pollutants from lead-zinc mining areas poses a significant threat to the environment, making pollution tracing crucial for environmental protection. However, the complexity of carbonate mining areas makes tracing these pollutants challenging. This study used δ34SSO4 and δ18OSO4 isotopes combined with the Stable Isotope Mixing Models in R (SIMMR) to assess anthropogenic sulfate sources in the Daliangzi mining area. The river water types were mainly Ca2+-Mg2+-HCO3−, and SO42−, which are significantly influenced by dolomite dissolution. The δ34SSO4 values ranged from 6.47‰ to 17.96‰ and the δ18OSO4 values ranged from −5.66‰ to 13.98‰. The SIMMR results showed that evaporite dissolution in tributaries, driven by gypsum, contributed 31% of sulfate, while sulfide oxidation, sewage, and atmospheric deposition contributed 19%, 18%, and 24%, respectively. The tailings pond near Xincha Creek has a higher sulfate release potential than the processing plant near Cha Creek. In the mainstream, sulfide oxidation contributed 25%, primarily from mine drainage. Anthropogenic sources, including sulfide oxidation, fertilizers, and sewage, made up about 50% of the total sulfate, with sulfide oxidation accounting for half of this input. The strong correlation between the Zn and SO42− concentrations (R2 = 0.82) and between the Zn and the contribution from the sulfide oxidation (R2 = 0.67) indicates their co-release during sulfide oxidation, making SO42− a proxy for tracing Zn sources. This study highlights the utility of δ34SSO4 and δ18OSO4 with SIMMR in tracing anthropogenic inputs and underscores the significant impact of mining on river systems and the sulfur cycle. [ABSTRACT FROM AUTHOR]

The characteristics and hazards of acid coal mine drainage (ACMD) were introduced, and the treatment methods of ACMD were described. Techniques that could be used for source prevention and process containment were analyzed. The widely used terminal treatment technologies at present were summarized, such as the active treatment technology based on neutralization, sulfidation, adsorption and membrane technology, and the passive treatment technology based on chemical, biological and chemical-biological combined method. It was summarized and concluded that the multi-technology combination process was the main trend of engineering application and an effective way for large-scale collaborative treatment of ACMD. Finally, the development prospect of ACMD treatment method was prospected. [ABSTRACT FROM AUTHOR]

This study introduces a novel mathematical approach rooted in X-ray spectroscopy principles to evaluate the oxidation state of sulfur, which is then applied in concrete and cementitious materials. Unlike previous studies that relied on an empirical quadratic relationship based on the ratios of characteristic X-ray lines (SKα, SKβ, and SKβ') for sulfur oxidation state determination, unique linear relationships between the intensities of the three X-ray lines for each oxidation state and total sulfur were utilized. Rational equations are then derived by combining these linear relationships for each species. Two independent rational calibration curves are constructed using the SKβ/SKα and SKβ'/SKβ ratios for samples containing sulfide-sulfate mixtures, irrespective of total sulfur concentration within the range of 0.3% to 2.0% by weight of concrete. These equations demonstrated interchangeability across three simulated matrices (Portland cement, concrete, and silica) and two sulfide species (pyrrhotite and pyrite). Absolute quantification of sulfide and sulfate species in concrete is achieved by independently measuring total sulfur. Compared to previous quadratic and linear equations, this approach is shown to minimize the difference between the experimental and calculated ratios of the calibration samples. Agreement was also observed between the sulfate ratio calculated through the rational approach and gravimetric analysis for concrete samples. [ABSTRACT FROM AUTHOR]

The impact of heavy fuel oil (HFO) on the chemical and isotopic composition of submicron particulate matter (PM1) was investigated. For this purpose, we conducted an analysis of water-soluble inorganic ions (WSIIs) and multiple isotopes (δ34S, δ13C, 14C) of PM1 and SO2 collected during two heating periods: before (2021–2022) and during the use of HFO (2022–2023) in Vilnius, Lithuania. The results showed that the combustion of HFO increased the concentrations of SO2 (by 94%) and PM1-related sulfate (by 30%). It also altered the chemical composition of PM1, with sulfate becoming the predominant component (~40%) of WSIIs. The stable sulfur isotope ratios of SO2 (δ34SSO2) and sulfate (δ34SPM1) shifted significantly to more negative values (δ34SSO2 = 0.4‰, δ34SPM1 = −0.3‰) compared to the previous heating period. Anticorrelation between δ13C and δ34S values indicated increased contributions of 13C-enriched fossil fuel sources (coal and HFO) in EC, although the share of fossil fuels in elemental carbon (EC) slightly decreased during the HFO period. The combustion of HFO affected the concentrations of PM1 chemical components and substantially impacted the isotopic composition and source contributions of sulfate and EC. [ABSTRACT FROM AUTHOR]

This study examined the associations of long-term exposure to ambient fine particulate matter (PM2.5) compositions/ozone with methylation of peripheral brain-derived neurotrophic factor (BDNF) promoters. A total of 101 participants were recruited from a cohort in Shijiazhuang, Hebei province, China. They underwent baseline and follow-up surveys in 2011 and 2015. DNA methylation levels were detected by bisulfite-PCR amplification and pyrosequencing. Participants' three-year average levels of PM2.5 compositions and ozone were estimated. Bayesian kernel machine regression (BKMR) models were used to examine the joint effects of pollutants on methylation levels. Exposure to PM2.5 compositions and ozone mixtures at the 75th percentile was associated with increased methylation levels at CpG2 of BDNF promoter (203%, 95% CI: 89, 316) than the lowest level of exposure, and sulfate dominated the effect in the BKMR models.Our findings provide clues to the epigenetic mechanisms for the associations of PM2.5 compositions and ozone with BDNF. [ABSTRACT FROM AUTHOR]

Gypsum is a common mineral at Gale crater on Mars, currently being explored by the Mars Science Laboratory (MSL) rover, Curiosity. In this paper, we summarize the associations of gypsum with other sulfate minerals (bassanite, anhydrite, jarosite, starkeyite, and kieserite) from the lowest levels of the crater's northern moat zone (Aeolis Palus) up through ~0.8 km of the stratigraphic section in the lower slopes of the sedimentary mound developed around the central peak, Aeolis Mons (informally, Mount Sharp). The analysis is based on results from the CheMin X-ray diffraction instrument on Curiosity, supplemented with information from the rover's versatile instrument suite. Gypsum does not occur with the same frequency as less hydrous Ca-sulfates, likely, in most cases, because of its dehydration to bassanite and possibly to anhydrite. All three of these Ca-sulfate phases often occur together and, along with other sulfates, in mixed assemblages that are evidence of limited equilibration on a cold, dry planet. In almost all samples, at least one of the Ca-sulfate minerals is present, except for a very limited interval where jarosite is the major sulfate mineral, with the implication of more acidic groundwater at a much later time in Gale crater's history. Although observations from orbit reveal a sulfate-rich surface, currently active dark basaltic dunes at Gale crater have only small amounts of a single sulfate mineral, anhydrite. Gale crater has provided the most complete mineralogical analysis of a site on Mars so far, but the data in hand show that Gale crater mineralogy is not a blueprint with planet-wide application. The concurrent study of Jezero crater by the Mars 2020 mission and comparisons to what is believed to be the most extensive deposit of gypsum on Mars, in the dune fields at the north polar ice cap, show significant diversity. Unraveling the stories of gypsum and other sulfates on Mars is just beginning. [ABSTRACT FROM AUTHOR]

The synchrotron technique of micro X-ray absorption near-edge structure spectroscopy at the sulfur K-edge (S-XANES) provides a unique opportunity to measure the proportion of different oxidation states of sulfur (S) in silicate glasses. Although applied extensively in the analysis of basaltic silicate glasses, few S-XANES studies have investigated variations in S oxidation states with fO2 in felsic silicate glasses. In addition, no study has systematically compared the S-XANES results obtained from the same samples at different photon flux densities to quantify the relationship between exposure time and changes in S speciation in silicate glass, as has been done for Fe and V. This study evaluates observed differences in S speciation measured in experimentally produced H2O-saturated dacitic glasses over a range of reducing to oxidizing conditions (from log fO2 = ΔFMQ-0.7 to ΔFMQ+3.3; FMQ is the fayalite-magnetite-quartz mineral redox buffer) and equilibrated at 1000 °C and 300 MPa. S-XANES spectra were collected at three different photon flux densities using three microspectroscopy beamlines. As is observed in S-XANES analyses of basaltic silicate glasses, beam-induced changes to the S6+/ΣS are observed as a function of photon flux density and beam exposure time. Our results demonstrate that silicate glasses of dacitic composition undergo beam-induced photo-reduction in samples equilibrated at ΔFMQ > +1.75 and photo-oxidation if equilibrated at ΔFMQ < +1. The time required to observe beam-induced changes in the spectra varies as a function of flux density, and our study establishes an upper photon density limit at ~1.0 × 1012 photons/μm2. The S6+/ΣS calculated from spectra collected below this absorbed photon limit at intermediate flux densities (~1–4 × 109 photons/s per μm2) are affected by beam damage, as no conditions were found to be completely free of beam-induced changes. However, the S6+/ΣS ratios calculated below the limit at intermediate flux densities are consistent with thermodynamic constraints, demonstrating that S6+/ΣS ratios calculated from S-XANES spectra can be considered reliable for estimating the oxygen fugacity. Our results carry important implications for the S budget of felsic magmas and dissolution mechanisms in evolved melts. While our results from all three flux densities show the presence of S4+ dissolved in relatively oxidized (ΔFMQ > +1.75) dacitic glass, even in the spectra exposed to the lowest photon densities, we are unable to rule out the possibility that the S4+ signal is the result of instantaneous X-ray irradiation induced beam damage using S-XANES alone. When our spectra are compared to S-XANES spectra from basaltic silicate glasses, important differences exist in the solubility of S2− and S6+ between dacitic silicate melts, pointing to differences in solubility mechanisms as melt composition changes. This study highlights the need for further investigation into beam damage systematics, presence of S4+, and the solubility mechanisms of different oxidation states of S as silicate melt composition changes. [ABSTRACT FROM AUTHOR]

Antimonate (Sb(V)), sulfate and acid orange 7 (AO7) are common pollutants in printing and dyeing wastewater. Currently, there have been no reports about the effects of sulfate and AO7 on Sb(V) removal by anaerobic granular sludge (AnGS). In this study, the Sb(V) removal and Sb(Ш) accumulation was revealed in presence of sulfate and AO7, and the role of adding granular activated carbon (GAC) was investigated. Results showed that sulfate inhibited Sb(V) removal by AnGS (S + Sb, k = 0.101). GAC alleviated the inhibition of sulfate on Sb(V) removal and Sb(V) removal rate increased by 1.9 times (GAC + S + Sb, k = 0.187). Meanwhile, GAC promoted sulfate reduction by AnGS. AO7 inhibited sulfate reduction, thereby alleviating the inhibition of sulfate on Sb(V) removal, and Sb(V) removal rate increased by 1.5 times (S + Sb + dye, k = 0.147). When Sb(V), sulfate and AO7 coexisted, adding GAC actually inhibited Sb(V) removal (GAC + S + Sb + dye, k = 0.067), which may be due to GAC promoted the reduction of sulfate and AO7 by AnGS. The microbial community analysis revealed that Acinetobacter genus was related to Sb(V) reduction, with higher relative abundance in GAC + S + Sb (49.4%) and S + Sb + dye groups (28.9%). These results provided guidance for anaerobic treatment of printing and dyeing wastewater. [ABSTRACT FROM AUTHOR]

Sulfide is a toxic and hazardous substance in the agricultural environment, which can cause damage to humans and livestock when exposed to large amounts of air. In this study, we performed one-factor optimization of the culture conditions and culture fractions of the Cellulosimicrobium sp. strain L1 and combined it with a biological trickling filter cell for the degradation of hydrogen sulfide for 24 consecutive days. The degradation effect of strain L1 and the biological trickling filter (BTF) on hydrogen sulfide was investigated, and the changes in intermediate products in the degradation process were briefly analyzed. The results showed that strain L1 had the highest conversion efficiency when incubated with 3 g/L sucrose as the carbon source and 1 g/L NH4Cl as the nitrogen source at a temperature of 35 °C, an initial pH of 5, and a NaCl concentration of 1%. The concentration of thiosulfate increased and then decreased during the degradation process, and the concentration of sulfate increased continuously. When strain L1 was applied to the biological trickling filter, it could degrade 359.53 mg/m3 of H2S. This study provides a deeper understanding of sulfide degradation in biological trickling filters and helps promote the development of desulfurization technology and the treatment of malodorous gasses produced by the accumulation of large quantities of livestock manure. [ABSTRACT FROM AUTHOR]

This corrigendum addresses an error in the default seawater dimethylsulfide (DMS) climatology used in a study on the influence of coral-reef-derived DMS on the atmosphere of the Great Barrier Reef. The correction states that the correct climatology should be Kettle et al. (1999) instead of Lana et al. (2011). However, this correction does not impact the study's results, and no new seawater DMS measurements for the Great Barrier Reef region have been included in newer climatologies. The document also references three scientific articles that may be relevant to library patrons researching climate and oceanic processes. [Extracted from the article]

Marine dimethylsulfide (DMS) is an important source of natural sulfur to the atmosphere, with potential implications for the Earth's radiative balance. Coral reefs are important regional sources of DMS, yet their contribution is not accounted for in global DMS climatologies or in model simulations. This study accounts for coral-reef-derived DMS and investigates its influence on the atmosphere of the Great Barrier Reef (GBR), Australia, using the Australian Community Climate and Earth System Simulator Atmospheric Model version 2 (ACCESS-AM2). A climatology of seawater surface DMS (DMSw) concentration in the GBR and an estimate of direct coral-to-air DMS flux during coral exposure to air at low tide are incorporated into the model, increasing DMS emissions from the GBR region by 0.02 Tg yr-1. Inclusion of coral-reef-derived DMS increased annual mean atmospheric DMS concentration over northeastern Australia by 29%, contributing to an increase in gas-phase sulfate aerosol precursors of up to 18% over the GBR. The findings suggest that the GBR is an important regional source of atmospheric sulfur, with the potential to influence local-scale aerosol-cloud processes. However, no influence on sulfate aerosol mass or number concentration was detected, even with a reduction in anthropogenic sulfur dioxide emissions, indicating that DMS may not significantly influence the regional atmosphere at monthly, annual or large spatial scales. Further research is needed to improve the representation of coral-reef-derived DMS in climate models and determine its influence on local, sub-daily aerosol-cloud processes, for which observational studies suggest that DMS may play a more important role. [ABSTRACT FROM AUTHOR]

At low pH, red blood cells (RBCs) are unable to maintain their disc shape and become stomatocytes. At the same time, at pH 5.0 of a sulphate medium, under conditions of mechanical mixing of the cell suspension, RBCs are partially retransformed into discoid forms, whereas in a chloride medium (pH 5.0) this transformation is observed to a high degree. This indicates that the chloride-binding sites of RBC membranes may be an additional link in the regulation of the shape of RBC under conditions of mechanical action on the cell suspension. The work investigated the change in the RBC shape at a normal pH value (7,4) due to the replacement of Na2SO 4 in the medium with NaCl and recording an increase in the intensity of fluctuations in optical density (OD), as an indicator of an increase in the level of discoid cells (normocytes) in a stirred cell suspension. It has been 3 established that in a medium containing Na2SO4 (110 mmol/l), RBCs are transformed into small stomatocytes within ~20 s. With an increase in NaCl concentration in the range of 15-105 mmol/l, an increase in the level of discoid cells is noted. Increasing the NaCl concentration from 105 to 150 mmol/l, on the contrary, causes a decrease in the level of discoid cells. With the exception of mechanical mixing in a medium with NaCl concentrations of 30-90 mmol/l, RBCs are morphologically stomatocytes. Whereas in a medium containing 150 mmol/l NaCl, RBC are represented by disc-echinocytes and echinocytes. The results obtained show that mechanical mixing of the cell suspension promotes the retransformation of stomatocytic RBCs into discoid forms. The weakening of the retransforming efficiency of mixing with an increase in the NaCl concentration in the medium from 105 to 150 mmol/l and the development of echinocytosis at 150 mmol/l NaCl indicates the existence of 2 types of sites for chloride. Сhloride binding to type 1, at a NaCl concentration in the medium of 15-105 mmol/l, leads to the establishment of discoid forms of RBC. Chloride binding to type 2 sites, at a NaCl concentration in the medium of 105-150 mmol/l, leads to the development of echinocytosis. The retransforming property of mechanical stirring may be associated with a change in the degree of chloride binding to these types of sites. [ABSTRACT FROM AUTHOR]

The metal-organic framework-derived sulfate hydrates exhibit exceptional energy storage performance due to their remarkable synergistic effect. In this study, the volcanic rock-like structure of nickel and cobalt sulfates hydrates (VNCSH) was derived in situ using a nickel-cobalt metal-organic framework as a substrate by a solvothermal method. Through the characterization analysis, the structure continues the porous structural characteristics of MOF materials with abundant active sites and prominent crystal morphology, which is conducive to the full contact with the electrolyte, accelerates the ion transfer, and improves the stability of the material. The VNCSH as an electrode has a high specific capacity of 1418.2 F g−1 at a current density of 2 A g−1 and maintains a high capacity of 870.9 F g−1 when the current density is increased to 10 A g−1. Furthermore, the assembled VNCSH//AC asymmetric supercapacitor device demonstrated a remarkable energy density of 146.2 Wh kg−1 at a power density of 725.8 W kg−1, while maintaining a capacity retention of 66.2% after undergoing 6000 cycles at a current density of 10 A g−1. These results indicate that VNCSH with volcanic rock-like morphology holds significant promise for advanced supercapacitor applications. [ABSTRACT FROM AUTHOR]

Control of sulfate‐induced melt fining without excessive foaming is one of the critical steps in maintaining the stability of E‐glass fiber manufacturing processes. Besides, the efficiency of combustion or energy utilization is directly affected by the extent of the melt‐foaming. A fundamental understanding of key factors affecting melt foaming under the simulated oxy‐fuel combustion environment will enable commercial E‐glass fiber production to optimize both batch chemistry and operation conditions to achieve adequate furnace control. In this study, six types of E‐glass batches with the same target glass composition were prepared by using four different CaO sources; calcined limes with different SO3 contents, limestone, limestone with sodium sulfate, and a mixture of limestone and calcined lime. All batch samples were examined by HTMOS‐EGA system (high temperature melting observation system with evolved gas analysis). HTMOS enables monitoring batch‐to‐melt conversation steps by using a high‐resolution camera and EGA detects the evolved reaction gaseous, such as CO, CO2, and SO2 via an Fourier transform infrared (FTIR) gas analyzer. Gases of water vapor, N2, and O2 were introduced accordingly into the fused quartz crucible to simulate similar oxy‐fuel atmosphere of the furnace operation. This study aimed to investigate the effects of different SO3 contents in batches and different raw material chemistries on the foam formation in E‐glass melts under the oxy‐fuel atmosphere. Different raw materials were characterized by mineralogical analysis, chemical analysis, particle size distribution, chemical oxygen demanding (COD) level, and Brunauer–Emmett–Teller (BET) analysis. Although some of the batches contained the same SO3 content, different foam formations resulted from the effect of the batch chemistry. Our detailed HTMOS‐EGA investigations show that not only SO3 content in the batch affects foam formation in E‐glass melts, but also raw material chemistry and particle size have strong effects on the melt foaming in E‐glass batch melting, especially for those of ingredients having hydroxide phases and/or finer particles with higher specific areas. [ABSTRACT FROM AUTHOR]

Magnesium and sulfate are a determinant key in CaCO3 mineralization. However, the works of the literature have failed to provide a clear understanding of how these ions influence the nucleation‐growth of CaCO3 precipitation. Our study uses an electrochemical method, having for principle to impose a dissolved oxygen reduction potential on gold (111) films. This technique that allows the exclusive and controlled crystallization of epitaxial calcite established an ideal system for the study of foreign ions influence. The polymorph, composition and morphology of crystals are characterized using scanning electron microscopy (SEM) coupled with X‐ray energy dispersive spectroscopy (EDS) and Raman spectroscopy. The results demonstrate that the increase of calcium concentration in calcocarbonic pure solution enhances the nucleation and then the growth of calcite crystals without affecting their morphology and their orientation. However, the magnesium directly modifies the surface morphology of calcite as a consequence of Mg substitution to calcium ions and the inhibitive effect of magnesium is assured by an incorporation mechanism. In the matter of sulfate ions influence, the experimental results indicate that SO42− slows down the epitaxial calcite nucleation by substituting itself to carbonate ions preferentially in the center of the crystals facets causing an enlargement of the lattice parameter. [ABSTRACT FROM AUTHOR]

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Three new monosulfated polyhydroxysteroid glycosides, spiculiferosides A (1), B (2), and C (3), along with new related unsulfated monoglycoside, spiculiferoside D (4), were isolated from an ethanolic extract of the starfish Henricia leviuscula spiculifera collected in the Sea of Okhotsk. Compounds 1–3 contain two carbohydrate moieties, one of which is attached to C-3 of the steroid tetracyclic core, whereas another is located at C-24 of the side chain of aglycon. Two glycosides (2, 3) are biosides, and one glycoside (1), unlike them, includes three monosaccharide residues. Such type triosides are a rare group of polar steroids of sea stars. In addition, the 5-substituted 3-OSO3-α-L-Araf unit was found in steroid glycosides from starfish for the first time. Cell viability analysis showed that 1–3 (at concentrations up to 100 μM) had negligible cytotoxicity against human embryonic kidney HEK293, melanoma SK-MEL-28, breast cancer MDA-MB-231, and colorectal carcinoma HCT 116 cells. These compounds significantly inhibited proliferation and colony formation in HCT 116 cells at non-toxic concentrations, with compound 3 having the greatest effect. Compound 3 exerted anti-proliferative effects on HCT 116 cells through the induction of dose-dependent cell cycle arrest at the G2/M phase, regulation of expression of cell cycle proteins CDK2, CDK4, cyclin D1, p21, and inhibition of phosphorylation of protein kinases c-Raf, MEK1/2, ERK1/2 of the MAPK/ERK1/2 pathway. [ABSTRACT FROM AUTHOR]

This experimental study is carried out in order to improve the properties of sulfate-attacked concrete. The concrete specimens were immersed in 15% Na2SO4 solution before being protected with a concrete repairing agent (CRA). The effects of sulfate corrosion time, the curing time after being attacked, and the concrete repairing agent on concrete were investigated. The experimental results indicate that the properties slightly increased after being attacked by sulfate for 60 days than for 30 days. However, they decreased after being attacked by sulfate for 90 days. CRA could effectively improve the properties of sulfate-attacked concrete. After being re-cured for 7 days, the properties of the sulfate-attacked concrete were significantly improved in comparison with those of the specimens taken out from the sulfate solution immediately. When the specimens were attacked for three months, the compressive strength of specimens coated with CRA was increased by 6.1%, 6.4%, and 6.4% compared to that of the specimens without CRA after being cured for 7 to 56 days, respectively. The carbonation depth of concrete specimens with CRA was reduced by 4.6%, 8.3%, and 4.9%, respectively. However, the chloride ion permeation coefficient of concrete with CRA decreased by 20.3%, 28.5%, and 28.7%, respectively, for the concrete immersed in sulfate for one month. [ABSTRACT FROM AUTHOR]

The International Maritime Organization (IMO) has formulated stringent ship emission regulations, and the global fuel sulfur limit of 0.50% became effective in 2020. Kitakyushu City is in the coastal suburbs of western Japan, and PM2.5 had already decreased prior to the global low-sulfur regulation, with concentrations in 2017, 2018, and 2019 of 12.2, 13.4, and 8.1 µg·m−3, respectively. The loading particles of the air masses passing through the Bohai Sea, Yellow Sea, and East China Sea in 2019 decreased to 3.4 µg·m−3, which was obviously higher than that of other air masses (0.5 µg·m−3), and the contribution of nss-SO42− could reach 56%, followed by OC (23%) and NH4+ (21%). Moreover, the characteristics of typical ship-emitted metals (V, Ni, As, Sb, W, and Cd) also changed greatly. Their sum concentrations in 2017, 2018, and 2019 were 10.6, 11.1, and 6.9 ng·m−3, respectively, which showed an annual variation similar to that of nss-SO42−. As for the particle exposure risk, the lowest chronic effect and carcinogenic risk were observed in 2019, with hazard indices (HI) for adults and children of 0.9 and 7.6, and carcinogenic risks (CRs) of 3.8 × 10−5 and 8.4 × 10−5, respectively. In this study, the health risks as well as air quality prior to the enforcement of the MARPOL Treaty in the leeward area of the Asian continent were totally and more precisely studied and evaluated based on the annual dataset; revealing the influence of trans-boundary transportation under individual Chinese regulations on the particle characteristic variations in Kitakyushu, Japan. [ABSTRACT FROM AUTHOR]

Dimethyl sulfide (DMS) is the largest source of natural sulfur in the atmosphere and undergoes oxidation reactions resulting in gas‐to‐particle conversion to form sulfate aerosol. Climate models typically use independent chemical schemes to simulate these processes, however, the sensitivity of sulfate aerosol to the schemes used by CMIP6 models has not been evaluated. Current climate models offer oversimplified DMS oxidation pathways, adding to the ambiguity surrounding the global sulfur burden. Here, we implemented seven DMS and sulfate chemistry schemes, six of which are from CMIP6 models, in an atmosphere‐only Earth system model. A large spread in aerosol optical depth (AOD) is simulated (0.077), almost twice the magnitude of the pre‐industrial to present‐day increase in AOD. Differences are largely driven by the inclusion of the nighttime DMS oxidation reaction with NO3, and in the number of aqueous phase sulfate reactions. Our analysis identifies the importance of DMS‐sulfate chemistry for simulating aerosols. We suggest that optimizing DMS/sulfur chemistry schemes is crucial for the accurate simulation of sulfate aerosols. Plain Language Summary: Dimethyl sulfide (DMS) is a sulfur‐bearing gas predominantly emitted from marine biological activity. DMS is the largest natural contributor to the global sulfur cycle, but its contribution is highly uncertain. Representing the complex chemical conversion of DMS to form natural sulfur atmospheric particles accurately in Earth System Models is difficult. Complex atmospheric chemistry is expensive to implement, therefore simplistic approaches to represent the chemistry are used. Here we examine the variability between different chemistry schemes. To achieve this, we employ a state‐of‐the‐art Earth System Model to compare seven simulations with differing sulfur‐related chemical reactions. We show that sulfate chemistry contributes to large uncertainties in aerosol and cloud formation. This work underscores the need to improve sulfur chemistry to improve the accuracy of cloud and aerosol projections in a warming world. Key Points: The simulated spread in aerosol optical depth and cloud droplet number concentration is more than twice as large as the change from pre‐industrial to present‐daySimulations with similar Dimethyl sulfide burdens have very different sulfate burdens driven by the different sulfate mechanisms/oxidation pathwaysConstraining the chemistry of atmospheric sulfur is critical to constrain aerosol‐cloud interactions [ABSTRACT FROM AUTHOR]