Sulfate Research Articles

Exploring the feasibility of using fluidized bed homogeneous crystallization technology to recover sulfate ions from briny water as calcium sulfate pellets

The increasing salinity of water sources poses significant operational and environmental challenges, highlighting the importance of developing efficient methods for recovering [SO42−] ions from briny wastewater. In this study, the potential of fluidized bed homogeneous crystallization (FBHC) technology for recovering [SO42−] ions from briny water is explored. FBHC is an innovative technique that enhances scalability and separation efficiency by promoting the growth of crystalline particles in a fluidized state. To achieve maximum [SO42−] recovery and maintain stable fluidized bed conditions, a pH of 8 is recommended. A removal ratio (RR) of 71 % was recorded at a [SO42−] concentration of 0.14 M. Various [SO42−] concentrations exhibited a molar ratio (MR) of [Ca2+]/[SO42−] = 1.5. Smaller particles, which are more soluble and exhibit less nucleation, are typically formed under conditions with lower pH and [Ca2+] levels. Intermediate-sized particles are favored at neutral to slightly alkaline pH levels and near-stoichiometric [Ca2+]/[SO42−] MR. Greater calcium content and higher pH values promote the development and agglomeration of larger particles, with 50 % of the particles exceeding an average size of 0.38 mm. In the XPS study of CaSO4 crystals (gypsum), the Ca 2p1/2 and Ca 2p3/2 peaks are observed at binding energies of 351.5 eV and 347.7 eV, respectively. Gypsum is identifiable due to the presence of clear and distinct peaks in XRD patterns. SEM analysis reveals the coexistence of amorphous patches and tiny crystalline domains on the surface. These gypsum crystals resemble stacked needle-like structures accompanied by small, powdery crystals. In an acidic environment, the primary phase is CaSO4·2H2O, which generates well-formed, elongated, or tabular crystals that are characteristic of gypsum. The FBHC process, characterized by a high crystallization ratio (CR = 68 %) and the recovery of crystal pellets (>0.3 mm), significantly reduces sludge production compared to traditional chemical precipitation methods. Its cost-effectiveness and recoverability make FBHC a promising technology for the recovery of sulfate ions from briny wastewater.

Degradation mechanism of dual-phase thermal barrier coatings Gd2Zr2O7 + 8YSZ under hot corrosion in pure Na2SO4

AbstractThe research presented in the article concerns the identification and characterisation of degradation mechanisms of two-phase coating thermal barriers based on the 8YSZ/Gd2Zr2O7 (8YSZ/GZO) system, and analysed under the conditions of exposure to pure sulphate salts of the Na2SO4 type. The scope of the presented research included the characterisation of microstructural phenomena in conditions of heating at a temperature of 920 °C for 240 h, followed by heating at a temperature of 970 °C for another 96 h until visually significant degradation effects of the ceramic coating were achieved. Detailed studies of the phase and chemical composition using XRD and SEM/EDS methods were carried out on the surface of the tested coatings and their cross sections to describe microstructural phenomena. The analysis of the phase composition of the ceramic layer showed the course of degradation processes based on the disintegration of the pyrochlore phase into intermediate forms of non-stoichiometric fluorite with the simultaneous enrichment of tetragonal zirconium oxide into a cubic form with a high content of the stabilising phase (Gd2O3). Tests on model powder systems confirmed the degradation mechanism of two-phase TBC coatings.

Effect of Deuteration on Raman Scattering in Single Crystals of Potassium Alum

ABSTRACTRaman spectra of KAl(SO4)2·12H2O and KAl(SO4)2·12D2O crystals in the range of 10–4000 cm−1 were experimentally obtained and studied. An increase in the number of sulfate ions, oriented by oxygen atoms towards the K+ ion, was detected upon deuteration of the sample. Low‐intensity Stokes components ν = 2485 cm−1 (ν = 1820 cm−1 for the deuterated crystal) were recorded, which indicates the formation of hydrogen bonds O–H•••SO42− (O–D•••SO42−), where the donors are water molecules of the [Al(H2O)6]3+ complex and the oxygen atoms of the sulfate ion act as acceptors. The decrease in the wavenumbers of internal vibrations of the sulfate ion during deuteration was explained by an increase in the strength of hydrogen bonds. The results obtained indicate the direct influence of deuteration on the degree of initial disordering of sulfate ions and on the stability of the crystal structure of potassium alum.

Characterization of Zinc Nanoparticles Synthesized Using the Mushroom, Pleurotus sajor-caju

Fungi including mushrooms contain various enzymes and biomolecules, making them an effective agent for synthesizing various nanoparticles. This study aimed to synthesize and characterize zinc nanoparticles using the zinc sulphate salt at the concentration of 1mM and the mushroom Pleurotus sajor-caju. The P. sajor-caju synthesized zinc nanoparticles were characterized using UV-Visible spectral analysis, Field Emission Scanning Electron Microscopy, and Fourier Transform Infrared Spectroscopy. They did not change the color and showed a characteristic surface plasmon resonance band peaking at 300nm. They were spherical and the particle size was found in the range of 7.29 nm to 13.27 nm. They showed ten bands at different stretching with wave numbers ranging between 675.17cm-1 and 3675.56cm-1. The presence of advantageous features in the zinc nanoparticles synthesized from P. sajor-caju revealed the usefulness of the synthesis of other metal nanoparticles from P. sajor-caju.

Removal of hexavalent chromium and pentavalent arsenic from aqueous solutions by adsorption on polyethylenimine-modified silica nanoparticles.

Chromium and arsenic are commonly found in water and wastewater as hexavalent chromium, Cr(VI), and inorganic arsenic species, such as pentavalent arsenic, As(V). In aqueous media, both Cr(VI) and As(V) exist predominantly in the form of oxy-anions. In our study, we prepared a polyethylenimine-silica composite material (SiO₂-PEI) as an adsorbent to study the adsorption capacity for chromate and arsenate ions. Polyethylenimine (PEI) can effectively bind negatively charged species through electrostatic interactions. The parameters that were evaluated, regarding the adsorption capacity were the effect of pH, the effect of the initial concentration of Cr(VI) and As(V), and the presence of other anions. Also, we examined the effect of Cr(VI) and As(V) on each other by studying the simultaneous removal of chromate and arsenate ions. Isotherm, kinetic, and thermodynamic analyses on the experimental data obtained were conducted. The results showed that the pH of the solution is affecting the charge density of PEI, and at pH 4, the lower value that was examined, the SiO₂-PEI exhibited higher adsorption capacity. The presence of other anions, such as phosphate, nitrate, and sulfate ions, had an adverse effect on the adsorption capacity of the SiO₂-PEI material for both chromate and arsenate ions. The adsorption capacity of arsenate was more affected by the presence of other anions compared to the chromate, and the higher impact was observed by the sulfate ions at pH 4, on the contrary for the chromate ions the higher impact was observed by the sulfate ions at pH 7 and by the phosphate ions at pH 4. Concerning the effect of temperature, the adsorption is an exothermic process and it was more favorable at lower environmental temperature. The study of simultaneous removal of Cr(VI) and As(V) declares the material's ability to accommodate both types of ions without requiring separate treatment steps. Addressing the simultaneous removal is essential for reducing the complexity of water treatment systems, lowering operational costs, and improving the safety of treated water.

Formation of Sodium Chloride on the Surface of Sulfate-Rich Gobi Desert Salt in Response to Water Adsorption.

Dust storms in arid regions transport desert salts and dust, affecting geochemical processes, atmospheric chemistry, climate, and human health. This study examines how the gas-salt interface composition of desert salt changes with varying relative humidity (RH), using ambient pressure X-ray photoelectron spectroscopy (APXPS), near-edge X-ray absorption fine structure (NEXAFS) spectroscopy, and molecular dynamics (MD) simulations. Ion chromatography analysis of desert salt indicates it is predominantly composed of sulfate, sodium, and magnesium ions, with traces of calcium, chloride, nitrate, and potassium ions. APXPS and NEXAFS surface analyses show that, at 0% RH, the gas-salt interface primarily features Na2SO4, with smaller amounts of MgSO4 and a trace of NaCl on the top layers. As humidity increases, the composition at the gas-salt interface changes, notably with Mg2+ binding to SO4 2- ions and a dominant NaCl formation throughout the studied surface depth. This shift indicates a transition from a sulfate- to a chloride-rich surface as humidity increases, contradicting MD simulations that predicted that on salt crystals covered by a submonolayer of water with electrolytes, chloride ions migrate toward the liquid-solid interface. This discrepancy indicates that other factors, like enhanced ionic mobility at grain boundaries, might drive the accumulation of chloride ions at the gas interface. The study emphasizes the crucial role of adsorbed water in ion migration and surface composition transformation of desert salts, affecting geochemical processes in arid regions.

The Need to Maintain the Quality of Naturally Pure Water of Sarayu River

Rivers are a link between human life and nature. All the ancient developed cities are situated on the banks of some river or the other ancient civilizations of India have developed on the banks of rivers. The river is helpful in both, flood and drought conditions, works to balance nature by absorbing the flood water inside itself and giving water to animals and humans during drought. In the present scenario, due to the increasing population of cities and the pollution arising from it, the water of rivers is getting polluted rapidly. Many rivers of the country are slowly disappearing and some rivers have water only during monsoon. Our country is slowly moving towards water crisis. To get out of this crisis, we all need a corrective change in behaviour along with scientific remedial system. The per capita availability of water has decreased significantly in the last 75 years. According to one figure, in 1951 the per capita was 5177 cubic meters but in the year 2011 only 1545 cubic meters of water is available per person. According to a study by the National Institute of Hydrology, India will have only 814 cubic meters of usable water per capita in 2025. When we studied the water of Sarayu river, it was found that all the parameters and heavy metals present in the water raised after monsoon are within the processed limit. When the properties of the water of Sarayu river were studied, surprising results came out. All the elements present in the water like calcium, magnesium, chloride, fluoride, alkalinity, nitrate ion, sulphate ion, arsenic and manganese etc. were within the required limits. Desirable limits of calcium, magnesium, chloride, alkalinity, nitrate ion, sulphate ion are 75 mg/l, 30 mg/l, 25 mg/l, 200 mg/l, 200 mg/l, respectively. The maximum values in pre-monsoon were found to be 38.47 mg/l, 26.24 mg/l, 15.9 mg/l, 192 mg/l, 0.20 mg/l and 20.10 mg/l respectively and in post-monsoon its maximum value was found to be 28.86 mg/l, 12.49 mg/l, 17.99 mg/l, 128 mg/l, 1.5 mg/l and 41.30 mg/l, respectively. The desirable limit of arsenic is 0.01, found to be 0.01 at some places in pre-monsoon but found to be nil in post-monsoon.

Evaluation of the Effect of pH and Concentration of Calcium and Sulfate Ions on Coal Flotation

The presence of calcium sulfate in the process water during the coal flotation greatly influences the recovery and selectivity of the separation. The concentrations of calcium and sulfate ions modify mineral hydrophobicity by altering surface properties resulting in depression or activation of the mineral species. An investigation to evaluate the statistical significance of the effect of the pH and concentration of calcium and sulfate ions on coal flotation was carried out; for this purpose, a 23 factorial design was implemented. A p-value < 0.05 was determined for the effect of calcium and sulfate ion concentrations, indicating that it is statistically significant. The interactions between factors (pH × calcium, pH × sulfate, calcium × sulfate and pH × calcium × sulfate) are also statistically significant, but the interaction between the concentration of calcium and sulfate ions has a notable influence according to the F statistic value. Employing 800 and 1920 mg/L of calcium and sulfate ions as experimental conditions yields a recovery of 90.4% with a concentrate containing 13% ash.

Ionic composition of snow cover on the territory of Siberia and the Far East

Long-term (from 2007 to 2022) observations of the dynamics of acidity, mineralization and ionic composition of snow cover in remote mountainous and lowland landscapes of Northern Asia were carried out. As a result, spatiotemporal changes in the molar concentration of basic (Ca2+, Mg2+, HCO3-, Cl- and SO42-) and nitrogen-containing (NH4+, NO3- and NO2-) ions were analyzed. It turned out that during the entire observation period, bicarbonate ions prevailed in all monitoring regions, even near the sea coasts, where there is an intensive intake of sulfate and chloride ions into the atmosphere. Until 2012, the molar concentration of these three anions was characterized by higher values, which decreased 3–8 times in subsequent years, this is especially noticeable for bicarbonate ions and to a lesser extent for chloride ions. The molar concentration of nitrogen-containing ions in the snow cover of Northern Asia was at a low level (especially nitrite ions). Ammonium ions were predominant throughout the observation period (especially in mountainous landscapes) and only in some years – nitrate ions.

Long-term electrochemical and biological study of archaeological iron-wood composite impregnated with 10 % PEG-200 solution

Electrochemical and biological analyzes were carried out on iron-wood composite archaeological objects from the “KASBA-OUDAYA” site in Morocco in 10 % PEG-200 solutions. Electrochemical measurements of steel combined with wood were made possible thanks to a proposed steel-wood configuration, with characterization of the surfaces after natural aging tests focused on the steel-wood interface by scanning electron microscope. The Mohr and Nephelometric method allow the determination of chloride and sulfate ions. While the biological study is ensured by isolation and enumeration of strains. The results revealed that the presence of wood in the PEG-200 solution decreased the pH of the solution and accelerated corrosion of steel. At the interface, we observe the development of pitting corrosion zones. In addition, PEG-200 solutions constitute a favorable environment for the proliferation of microorganisms.

A highly water-soluble phenoxazine quaternary ammonium compound catholyte for pH-neutral aqueous organic redox flow batteries

The pH-neutral aqueous redox flow battery (ARFB) is one of the most attractive flow batteries due to its non-corrosiveness, low-cost, and wider electrochemical stability window compared to those with acidic or alkaline electrolytes. However, there are few families of organic redox-active molecules available as catholyte materials for pH-neutral ARFBs. Herein, through incorporation of quaternary ammonium moiety into the redox-active phenoxazine nucleus, an organic catholyte material, N, N, N-trimethyl-2-(10H-phenoxazin-10-yl) ethan-1-aminium chloride (NEt-POZ) is achieved for pH-neutral ARFBs. The NEt-POZ has a high redox potential of 0.79 V versus SHE and rapid redox kinetics (0.23 cm s−1) as well as high water-solubility (∼2.6 M in H2O). Paired with a methyl viologen (MV) anolyte in the pH-neutral aqueous electrolyte, a viologen-phenoxazine ARFB full cell is assembled, which shows an open circuit voltage of ∼1.23 V. However, the results of long-term cycling experiments indicate low Coulomb efficiency and rapid declining capacity of the NEt-POZ catholyte. The mechanism analysis unveils that the unstable doubly oxidized tri-cations (NEt-POZ3+) formed via the disproportionation of radical di-cations (NEt-POZ2+) in solution readily react with chloride anions to form poly-chlorinated derivatives, which precipitate from the catholyte due to their poor water solubility, leading to a rapid decrease in capacity. When there is no chloride present in the electrolyte solution, highly reactive NEt-POZ3+ cations can interact with other counter-anions (such as sulfate and carbonate ions) and even water to form complex adducts.

Systematic long-term investigation on Cu2ZnCdS4 wide band gap semiconducting materials for optics and luminescence applications

Copper Zinc Cadmium Sulfide (Cu2ZnCdS4) semiconducting material compound synthesized using a new economic beneficial route. Copper sulfate, zinc sulfate, cadmium sulfate and thiourea salt solutions were utilized for Cu2ZnCdS4 compound formation. Basic characteristics like pH value, electrical conductivity, concentration measurements were investigated for several hundred samples. Optics transmittance was investigated by UV – Vis spectrophotometer within the 350 to 950 nm range. Photo luminescence measurement was examined by using photo–fluorometer. Optic properties of Cu2ZnCdS4 compound were investigated through photo-calorimeter measurements including mixed wavelength bands. The real time investigated noteworthy results from several hundred samples are presented and discussed.

Comparative study of pre- and post-Cu modified calcium-based desulfurizers: experimental and theoretical insights into adsorption vs. catalysis

This study focused on the dry desulfurization of calcium-based materials, with the aim of conducting an in-depth investigation into the mechanistic differences in desulfurization between traditional commercial calcium-based materials and their Cu-modified counterparts, utilizing experiments, reaction kinetics, and density functional theory (DFT). Through a fixed-bed reactor, factors affecting desulfurization efficiency were investigated, with characterizations pre- and post-desulfurization. The experimental results showed that Cu significantly improved desulfurization performance of calcium-based materials, shifting the mechanism from adsorption- to catalysis-dominated. Among factors, temperature notably influenced calcium-based materials. Reaction kinetics analyses revealed that temperature boosted both rates of the surface chemical reaction-controlled stage and the internal diffusion process, explaining its significant impact. DFT simulations indicated Ca(OH)2(101) surfaces strongly adsorbed reactants but suffered from saturation and competitive adsorption, hindering efficiency. In contrast, Cu-modified surfaces, while exhibiting reduced adsorptive capacity, introduced new catalytic sites with low energy barriers, thereby enhancing desulfurization efficiency, particularly in the presence of water, which can directly participate in the subsequent formation of sulfate ions.

Structural, Antioxidant, and Protein/DNA-Binding Properties of Sulfate-Coordinated Ni(II) Complex with Pyridoxal-Semicarbazone (PLSC) Ligand

The pyridoxal-semicarbazone (PLSC) ligand and its transition metal complexes have shown significant biological activity. In this contribution, a novel nickel(II)-PLSC complex, [Ni(PLSC)(SO4)(H2O)2], was obtained, and its structure was determined by X-ray crystallographic analysis, FTIR, and UV-VIS spectroscopy. The sulfate ion is directly coordinated to the central metal ion. The intermolecular stabilization interactions were examined using Hirshfeld surface analysis. The crystal structure was optimized by a B3LYP functional using two pseudopotentials for nickel(II) (LanL2DZ and def2-TZVP) together with a 6-311++G(d,p) basis set for non-metallic atoms. The experimental and theoretical bond lengths and angles were compared, and the appropriate level of theory was determined. The stabilization interactions within the coordination sphere were investigated by the Quantum Theory of Atoms in Molecules (QTAIM). The antioxidant activity towards hydroxyl and ascorbyl radicals was measured by EPR spectroscopy. The interactions between Human Serum Albumin (HSA) and the complex were examined by spectrofluorimetric titration and a molecular docking study. The mechanism of binding to DNA was analyzed by complex fluorescence quenching, potassium iodide quenching, and ethidium bromide displacement studies in conjunction with molecular docking simulations.

Probing the dual mechanism of load damage and flowing solution on sulfate attack resistance of alkali-activated slag concrete

Alkali-activated slag concrete (AASC) is a representative low-carbon green building material. To effectively characterize the sulfate attack resistance of AASC in complex environments, a self-designed simulation device for complex corrosion environments was used to study the sulfate attack mechanism and property deterioration law of AASC under the loads and flowing corrosion solutions. The results indicated that both load-induced damage and dissolution accelerated the transport of sulfate ions into the AASC. On the one hand, the load-induced damage and dissolution resulted in a decrease in the proportion of gel pores, reducing the electrostatic interaction between ions and the gel pore wall as well as the gel pore wall thinning effect. On the other hand, the load-induced damage and dissolution decreased the pH of the pore solutions in AASC, causing easier decalcification or dealumination of C-A-S-H gel under sulfate ion attack. This further accelerated the sulfate ion attack and deterioration of AASC.

Simultaneous recovery of ammonium sulfate and ice from aqueous solution using eutectic freeze crystallization process

This study investigated the feasibility of eutectic freeze crystallization (EFC) process for ammonium sulfate (AS) salt recovery from 41 wt% AS solution. The EFC experiments were conducted using a 1 L double-jacketed crystallizer coupled with a recirculating chiller under varying freezing time, seed mass and seed size. The EFC process demonstrated successful AS salt recovery and water purification with the highest ice purity attained at 96.28 %. The construction of a binary AS-water phase diagram allowed the determination of the eutectic temperature, which was found to be −19.06 °C at 40 wt% of AS solution. The results indicated that the increase in freezing time enhanced the AS nucleation rate, growth rate, yield and mean product crystal size. The introduction of seeding not only provided well-controlled crystal nucleation and growth during EFC process, but also promoted the formation of larger, well-structured crystals and reduced agglomeration. Overall, the EFC process is a viable and promising option for recovering AS from wastewater, which offers high potential towards achieving zero liquid discharge goal, i.e. a sustainable and efficient approach in managing industrial effluent rich in ammonium and sulfate contaminants.

Characterization of Sulfur Oxidizing Bacteria and Their Effect on Growth Promotion of Brassica napus L.

Oil seeds sector is one of the major dynamic components of the agriculture world. Oil seeds such as canola (Brassica napus) require a higher quantity of sulfur (S), which is supplied through inorganic fertilizers. However, the overapplication of agro-chemicals to get higher yields of crops is harming the soil health. Therefore, the application of bacterial cultures with plant growth-promoting activity as biofertilizers ensures soil health maintenance and enhances crop productivity. To achieve this aim, the present research was initiated by procuring three sulfur-oxidizing bacteria (SOBs), namely, SOB 5, SOB 10, and SOB 38, from the Microbiology Department, PAU. In the initial assessment, all three SOB cultures showed resilience to pesticide toxicity at the recommended dosage, with the exception of ridomil. These cultures were later characterized morphologically, biochemically, and at the molecular level using 16s rRNA resulting in their identification as Enterobacter ludwigii strain Remi_9 (SOB 5), Enterobacter hormaechei strain AUH-ENM30 (SOB 10), and Bacillus sp. 5BM21Y12 (SOB 38). Functional characterization of these SOB cultures revealed their ability to exhibit multifarious plant growth-promoting traits. Bacillus sp. 5BM21Y12 showed greater functional activity, including high P solubilization (14.903 µg/mL), IAA production (44.28 µg/mL), siderophore production (13.89 µg/mL), sulfate ion production (0.127 mM), ammonia excretion (2.369 µg/mL), and Zn solubilization (22.62 mm). Based on the results of functional and molecular characterization, Bacillus sp. 5BM21Y12 was selected for field trials by formulating different treatments. Composite treatment, T8 (100% S + Bacillus sp. + pesticides) significantly enhanced growth parameters (plant height, root, and shoot biomass), yield attributes (siliqua length, test weight, number of siliqua/plant), yield parameter (total biomass and seed yield), quality parameter (crude protein and oil) as compared to all other sole treatments employed in the field. A combined application of non-pathogenic Bacillus sp. 5BM21Y12, with good functional activity enhanced yield of crop due to synergistic and additive interaction with fertilizer/pesticides. As biofertilizer application reduces the input of pesticides/fertilizers new inoculant formulations with cell protectors and the development of compatible pesticides should be searched to assure the benefits of integrated treatment.

Sulcardine, an investigational multichannel blocker for atrial fibrillation with uniquely intense JTp inhibition to enhance safety

Abstract Background Sulcardine is a multi-ion channel blocker for treating atrial fibrillation (AF) with similar inhibitory potency on peak/late sodium, L-type calcium, and rapidly activating delayed-rectifier potassium (IKr) currents. The therapeutic effect of inhibiting IKr includes QT prolongation (accompanied by a proportional J to T peak [JTp] interval prolongation), which, when excessive, may cause malignant arrhythmias. As previously reported, sulcardine strongly mitigates the JTp increase that may contribute to excessive QT prolongation by inhibiting late sodium and L-type calcium currents, an intrinsic mechanism to protect from excessive IKr block. Purpose We explored the JTp mechanism, pharmacokinetics (PK), electrocardiogram (ECG) changes, safety, and drug-drug interaction (DDI) of a single sulcardine (as HBI-3000) intravenous (IV) infusion in healthy subjects. Methods An open-label Phase 1 study evaluated the PK interaction between sulcardine, dosed as a 350 mg 30-minute infusion of the sulfate salt HBI-3000, and a cytochrome P450 CYP2D6 enzyme inhibitor (paroxetine). Triplicate ECGs were extracted from continuous 12-lead Holter ECG recordings at baseline and 10 time points thereafter. Mean baseline-subtracted and heart rate-corrected QTcF (dQTcF), JTpc (dJTpc), and other ECG changes were calculated at each time point. Left ventricular ejection fraction (LVEF) was assessed at baseline, 30-, and 120-minutes post-infusion start by transthoracic echocardiography (TTE). Results 39 subjects received HBI-3000, 33 in the paired PK population. Expected ECG parameter changes proportional to sulcardine plasma concentrations were observed in the HBI-3000-alone portion of the study, including modest QTcF prolongation (Fig 1, blue slope, confidence band) and JTpc inhibition (Fig 1, red). The usual JTpc increase associated with IKr blockers, even those with mitigating channel block (such as the late sodium current), was not only reduced but actually reversed. We calculated the dQTcF change that would have been observed in the absence of JTpc reduction by sulcardine (Fig 1, green). Sulcardine reduced the QTcF increase that might have occurred by about 21 msec at the highest concentrations, and this mitigating effect was observed at all concentrations. No clinically significant safety findings or arrhythmias were observed. The most frequent TEAEs were nausea and headache (n=2 each [5.1%]). No LVEF changes were clinically significant. Sulcardine had minimal metabolic interactions. Conclusion Acute IV HBI-3000 administration resulted in no clinically significant safety findings, LVEF depression, or DDI with CYP2D6. Sulcardine facilitates QT prolongation, which has a therapeutic benefit in terminating AF, with simultaneous uncoupling and reversing of the JTpc interval increase, a potential mechanism for reducing proarrhythmic risk due to excessive QT prolongation.Figure 1.ECG Intervals vs Sulcardine Conc

Establishing fire protection patterns in wood using impregnation compositions from inorganic salts

An issue related to using inorganic salts for fire protection of wood is to ensure their flame-inhibiting ability and compatibility with wood and application technology. That is why the object of research was to establish the effectiveness of inhibitory properties of mixtures of inorganic salts during interaction with the flame and enabling interplay with wood. A synergistic increase in the inhibitory capacity of mixtures of aqueous solutions of salts of diammonium phosphate and ammonium sulfate at a ratio of 2:1, and for a mixture based on orthophosphoric acid, urea, and oxyethylidenediphosphonic acid in the concentration range of 20–25 % by mass, has been proven. During the interaction of the specified mixtures with the wood surface, it was found that after application to the wood surface, the dispersed component of the free energy of the wood surface decreased to zero; instead, the polar component increased 13 times, which indicates a change in the wood surface. During the tests of wood samples on the effect of the burner flame, it was found that the untreated sample ignited on second 53, and the flame spread throughout the sample for 102 s. On the other hand, the samples treated with a mixture of an aqueous solution of phosphate and ammonium sulfate, as well as a mixture of aqueous solutions based on orthophosphoric acid and urea and oxyethylidenediphosphonic acid, did not catch fire, the flame did not spread over the surface, and the flammability index was 0. The practical significance is that the results were taken into account when designing flame retardant compositions for wood. Thus, there are reasons to assert the possibility of targeted regulation of wood protection processes through the use of mixtures of inorganic salts capable of forming a protective layer on the surface of the material that inhibits the burning of wood

Associations of exposure to PM2.5 and its compounds with carotid intima-media thickness among middle-aged adults

BackgroundExposure to fine particulate matter (PM2.5) has been linked to an increased risk of atherosclerosis. However, it remains unclear whether specific compounds within PM2.5, rather than the overall mass, serve as a better indicator of adverse cardiovascular health outcomes associated with air pollution. MethodsIn this cross-sectional study, we included 3257 participants (aged 37–51 years) from the Coronary Artery Risk Development in Young Adults (CARDIA) study. Exposure to PM2.5 and its constituent compounds, black carbon (BC), ammonium, nitrate, organic matter, sulfate, mineral dust, and sea salt were included in the analyses. Carotid intima media thickness (cIMT; the average of common, bulb, and internal carotid) was measured by carotid ultrasonography. We assessed the cross-sectional associations of one-year exposure to PM2.5 and its compounds with mean cIMT using linear regression models adjusting for participants' demographics, individual- and neighborhood-level socioeconomic status, behavioral components, and health conditions. We also adopted Bayesian kernel machine regression (BKMR) models to investigate the association between the PM2.5 compound mixture and cIMT as well as the contribution of each compound to the association. ResultsGreater exposure to BC was associated with higher cIMT (mm) (β =0.034, 95 % CI = 0.019–0.049, per IQR increase [0.56 μg/m3] of BC) among participants with a mean age of 45.0, consisting of 45.9 % Black and 54.1 % White males and females. The association was generally consistent across participants' demographic characteristics. In our BKMR analysis, BC exhibited a dose-response association with cIMT with a high contribution to the association of cIMT with PM2.5 compound as a mixture (posterior inclusion probability [PIP]: 1.00). ConclusionsOur findings suggest that certain compounds of PM2.5, such as BC, may offer more reliable indications of the impact of air pollution on cardiovascular health.