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Background: This research investigated the effects of various iron fertilizers and the introduction of Piriformospora indica (P. indica) fungus on the biodegradation of diesel oil in soil experiencing water deficiency. Methods: The treatments included applying pure Fe at rates of 0, 60, and 90 kg/ha, derived from Fe sulfate (FeSO4) and Fe slag (containing 58.2 % Fe2O3), in a diesel oilcontaminated soil with concentrations of 0 % and 8 % (W/W). These treatments were implemented in a corn plant cultivation system, where the plants were inoculated with P.indica fungus under conditions of drought stress. After 90 days, the plant and soil Fe concentration was determined by atomic absorption spectroscopy (AAS). Furthermore, the extent of diesel oil bio-degradation in the soil was assessed. Results: Applying 90 kg/ha pure Fe from Fe sulfate and Fe slag significantly enhanced the bio-degradation of diesel oil in the soil by 13.2 and 16.1 %, respectively. However, the efficiency of this process was lower under drought-stress conditions. In addition, Plant inoculation with P.indica significantly enhanced the diesel oil bio-degradation of the soil contaminated with 8 % (W/W) diesel oil under drought stress by 15.7 %. Moreover, the soil microbial activity was significantly increased by 14.1 %. Conclusion: The combined use of P.indica, along with iron slag and iron sulfate, markedly enhances the biodegradation process of diesel oil within the soil. [ABSTRACT FROM AUTHOR]

The Middle Devonian (Eifelian) paleosol (PS) recently discovered in the area of Voronezh Anteclise has been studied in detail. The PS is developed from acid volcanic rock, rhyolitic tuff. The thickness of laterally continuous PS varies from 20 to 150 cm depending on the relief of the Proterozoic basement beneath it. The tuff contains the inclusions of allochthonous coal particles most part of which is partially or completely substituted by pyrite. The main part of coal particles belongs to the remnants of nematophytes (Nematophyta and Prototaxites). The absence of rhizoliths and the microstructure of plant debris suggest that the PS developed under primitive rootless vegetation. The set of obtained analytical characteristics demonstrates that this PS is an analogue of the modern acid sulfate soils. The PS formation was the result of predominantly chemical weathering initiated by pyrite oxidation. The following pedological characteristics were noted: kaolinite formation and redistribution; tonguing soil bottom; iron mobility; formation of iron- and gypsum-containing nodules; and in situ formation of gypsum, iron oxides, and iron sulfates. Characteristic of the PS top is an increase of Al2O3 and Fe2O3; the values of Al/Ti, Ba/Sr, and K/Rb ratios; and the lateritization index. The pedogenesis had the local (focal) character without formation of distinct soil horizons. [ABSTRACT FROM AUTHOR]

Objectives: This study aims to evaluate the success rate of formocresol and ferric sulfate through meta-analysis with trial sequential analysis (TSA). Method and materials: The protocol of the review was registered in the PROSPERO database (CRD 42018090044). Two independent reviewers used PubMed, Scopus and EBSCOhost databases to identify randomized clinical trials published from inception to June 2019. Patients undergoing pulpotomy therapy in vital primary molars with pulp exposure due to caries treated with formocresol and ferric sulfate were evaluated for clinical and radiographic success. Metaanalysis was conducted to evaluate the success at 6, 12, 18, and 24 months and TSA was performed for success at 24 months. Quality of evidence was determined by Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) analysis. Results: Eight clinical trials were included in metaanalysis. No difference was observed in the clinical and radiographic success rate between formocresol and ferric sulfate at 6, 12, 18, and 24 months. TSA identified required information size of 687 teeth for clinical success and 568 teeth for radiographic success. In addition, it demonstrated evidence for radiographic success rate at an anticipated intervention effect of 10% for formocresol over ferric sulfate. Conclusion: Formocresol and ferric sulfate show comparable clinical and radiographic success rates as pulpotomy material in primary molars at 24 months based on the studies with low to moderate quality of evidence. [ABSTRACT FROM AUTHOR]

The mineral waters of "Guber" Srebrenica are highly mineralized waters with a significant content of soluble iron. They belong to iron-sulfate waters, which are rich in arsenic and therefore also called iron-arsenic waters with low pH values. Some of the "Guber" waters of Srebrenica were used for therapeutic purposes in the past. Spectrophotometric methods were used for their characterization. Today, instrumental methods are known which are faster and more efficient. This work focusses on using the Inductively Coupled Plasma - Optical Emission Spectrometry (ICP-OES) for the characterization of Guber Srebrenica mineral waters. Two standards were used to determine the elemental composition of these mineral waters, which differ in concentration and number of elements present. The results obtained by this method for soluble iron from different sources were compared with the spectrophotometric method of iron determination. The obtained results show that the lower iron concentrations in the samples obtained by the ICP method coincide with the results of the spectrophotometric method. However, with higher concentrations of iron (Očna voda), the deviations of the ICP method from the standard spectrophotometric method are greater and this may be the subject of further research. There are also discrepancies in the results between the standards for lead and arsenic, with higher values occurring in the samples where standards with a smaller number of present elements were used, which necessitates the use of standard methods. [ABSTRACT FROM AUTHOR]

Agriculture is one of the economic activities with the most potential in Colombia, given its climatic and geographical conditions. Bean cultivation is classified as climbing, which grows in a branched way, and bushy, whose growth occurs up to 70 cm. The objective of this research was to study zinc and iron sulfates in different concentrations as fertilizers capable of increasing the nutritional value of kidney beans (Phaseolus vulgaris L.), whose strategy is known as biofortification, and thus determine the most effective sulfate. The methodology details the sulfate formulations, their preparation, the application of additives, sampling and quantification methods of total iron, total zinc, °Brix, carotenoids, chlorophylls a, b, and antioxidant capacity using the DPPH (2,2-diphenyl-1-picrylhydrazyl) method in leaves and pods. As for the results, it was found that biofortification with iron sulfate and zinc sulfate is a strategy that favors the country's economy and human health, because it allows the increase of minerals, antioxidant capacity and total soluble solids. [ABSTRACT FROM AUTHOR]

The Yenikapı (YK) 12 shipwreck is 1 of 37 shipwrecks found at Yenikapı, Istanbul. This merchantman has been dated to AD 672–876 by radiocarbon analyses. The conservation of YK 12, which was assembled with iron nails, was completed with the pre-impregnation of polyethylene glycol (PEG) and using vacuum freeze-drying processes. However, after conservation, dust formation was observed on some wooden parts of the shipwreck during storage. In this study, iron–sulfur-related problems detected in the woods of YK 12 were evaluated. We analysed samples taken from YK 12 to study the sulfur and iron content in woods from oak (Quercus), walnut (Juglans), and hornbeam (Carpinus), representing taxa with different wood properties. Fourier-transform infrared spectroscopy (FTIR) analyses, X-ray diffraction (XRD), and pH measurements were conducted on five samples. The results of these studies showed that the dust consisted of wood particles, PEG, and hydrated iron sulfates, such as FeSO4·4H2O and FeSO4·7H2O. Additionally, one sample included SiO2, whilst another exhibited a low pH value. These findings highlight the importance of optimum ambient conditions for the storage and display of these shipwrecks in order to prevent the irreversible degradation of YK 12 and other recovered shipwrecks. [ABSTRACT FROM AUTHOR]

Acid sulfate soils (AS-soils) are a common feature along coastlines in many countries that can have significant environmental and economic impacts. AS-soils oxidation may cause soil and water acidification, the release and mobilization of metals and the formation of new precipitated phases. In northern Sweden, some soils are already oxidized and constitute an environmental concern. This study aimed to analyze the geochemistry and mineralogy of AS-soils profiles by identifying element depletion and accumulation zones, the parent material, minerals that contribute to acidity and their oxidation products as well as anomalous element content values that could be related to anthropogenic sources. Two soil profiles were drilled close to the Lule River in Södra Sunderbyn, Luleå. The profiles were characterized by an oxidized zone (OZ) with a declining trend in element content, a transition zone (TZ) where elements tended to accumulate and a reduced zone (RZ) where elements had their maximum content. The pH was a key determinant of the element distribution. Cadmium, Co, Ni and Zn were found to be typical elements released into the environment during AS-soils oxidation. After sample incubation, pH measurements showed a pronounced decrease in layers with higher S and total organic carbon (TOC) content. Both profiles developed a larger thickness of potential acid-risk sediments according to S, TOC and pH measurements during incubation. Iron sulfides were identified as the main acidity generators, represented by an abundance of framboidal pyrites with a Mn-rich rim formed under anoxic-euxinic conditions. Iron sulfates and iron oxyhydroxides (FeOOH, FeOH 3) were identified as the most common products of oxidation processes. [Display omitted] • pH influenced the element distribution by forming depletion and accumulation zones. • Layers with high S and TOC content showed a pronounced pH decrease during incubation. • The AS-Soils parent material formed in a zone where anoxic-euxinic conditions prevailed. • Framboidal pyrites represent the most abundant iron sulfide and are the main acidity generator. [ABSTRACT FROM AUTHOR]

In this work, the conditions for the synthesis of open vase-like microcapsules with a size of 1–5 μm and 20–40 nm walls of NiFe0.3(OH)x layered double hydroxide were studied. These microcapsules were obtained by the rapid hydrolysis of microdroplets of a solution of a mixture of NiSO4 and FeSO4 salts at the surface of an alkali solution. A hypothetical model of successive chemical processes occurring at the interface during synthesis is presented. The features of the "rim" formation around each microcapsule hole from the wall material with a peculiar nozzle-like shape are noted. These microcapsules can be transferred to the surface of a nickel foil using the Langmuir–Schaefer (LS) method. During the transfer process, they are fixed to the surface in an oriented position with a "rim" that contacts the nickel surface. It was established that electrodes made of such a foil with a layer of microcapsules exhibit active electrocatalytic properties in the oxygen evolution reaction during the electrolysis of water in an alkaline medium. [ABSTRACT FROM AUTHOR]

Active polyethylene/carbon black films with the capability of controlled release of micronutrients were developed in this work. A simple technique allowed modifying film surface through the incorporation of different mineral particles (talc, zeolite and calcium carbonate), without altering material bulk properties. Particle distribution and dispersion on surface were analyzed by scanning electron microscopy (SEM); meanwhile, particle concentration was determined by thermogravimetric analysis (TGA). Particle adhesion on films surface was also determined. Saturated solutions of different micronutrients sources (iron, copper and manganese sulfates) were sprayed separately on surface-modified films. SEM, elemental mapping by energy-dispersive X-ray spectrometry (EDS) and X-ray diffraction (XRD) were used to verify the presence of salts on modified films. Finally, release of micronutrients (salts) in distilled water was studied by flame atomic absorption spectroscopy (FAAS). Surface-modified films allowed a controlled release of copper and iron sulfates in water up to a minimum time of 5 weeks. However, the release of manganese could be prolonged up to 1 week. The obtained results could be promissory for the development of active agricultural films with the capability of releasing micronutrients in a controlled manner to satisfy the nutritional requirements of crops, mainly in depleted soils. [ABSTRACT FROM AUTHOR]

Snow molds are an important group of diseases of amenity turfgrass in temperate climates. Acceptable control is typically achieved through one or two fungicide applications prior to snow cover, though there is increasing interest in exploring alternative control products such as iron sulfate and/or potassium phosphite. Previous research has demonstrated that poor snow mold control is achieved when these alternative products are applied once prior to snow cover, so the objective of this study was to assess their efficacy when applied repeatedly throughout the fall. Iron sulfate heptahydrate, potassium phosphite, and the fungicide propiconazole were applied six times, every 2 weeks, throughout the fall of 2019 at three locations in Wisconsin that typically produce high, medium, and low snow mold pressure. No reduction in disease relative to the nontreated control was observed at any location in response to the iron sulfate and potassium phosphite treatments. Propiconazole did provide effective snow mold control at the low and moderate pressure locations but not at the high pressure location. Both iron sulfate and potassium phosphite have shown efficacy against select turfgrass diseases, but do not appear to provide control of snow mold in areas where snow cover persists during winter. Core Ideas: Demand is increasing for alternative, nonfungicidal snow mold control strategies.Repeated applications of iron sulfate and potassium phosphite during the fall failed to suppress snow mold at three locations in Wisconsin.Repeated applications of propiconazole did provide effective control in low and moderate disease pressure environments, providing a potential control strategy for locations with few fungicides available. [ABSTRACT FROM AUTHOR]

Nickel is mostly extracted from sulfide ores, however, laterite ores account for over 60 pct of all nickel resources in the world, and despite its predominance, there is no well-established process to extract nickel from such ores. Nickel in laterites is hosted in many different compounds such as oxides, hydroxides, and silicates minerals. The sulfation-roasting-leaching process has the potential to change this scenario once it can be applied to all kinds of nickel laterite ores and does not consume much acid, as in the atmospheric leaching process. The main characteristic of the process is the iron sulfates decomposition during roasting steps, which produces sulfur trioxide (SO3). The sulfur trioxide is reactive with metals such as nickel and cobalt, converting them to soluble sulfates, and reducing acid consumption. Experiments were conducted to establish the optimal conditions to extract nickel from laterite ores using the sulfation-roasting-leaching process. Various parameters were investigated: water addition, sulfuric acid concentration, the number of heat-treatments steps, roasting temperature and time, leaching time, and solid/liquid ratio. Furthermore, the phase changes during thermal treatments were investigated to identify the mechanisms involved in the transformation of the minerals. Experimental results indicated that nickel forms sulfates through three different ways: reacting with H2SO4 during sulfation, with Fe2(SO4)3 (ferric sulfate) or Fe(OH)SO4 (basic iron sulfates) during the heat-treatments, and also throughout the leaching step due to iron-rich phase dissolution. More than 83.0 pct Ni, 90.0 pct Co, 61.3 pct Al, 17.3 pct Ca, 85.7 pct Mg, 87.5 pct Mn, 1.1 pct Ti, and 16.6 pct Fe were extracted under optimums conditions. [ABSTRACT FROM AUTHOR]

Lubricating oil-related engine emission reduction is now a key path to further control the engine-out emission level and to meet the restrict regulations, especially in the manner of particulate number emission. This work experimentally studied the contribution of lubricating oil and its key constituents to the particle emission via monitoring the combustion process and analyzing the particle physic-chemical characteristics. Two sets of experiments were conducted to understand how the lubricating oil alters the regular combustion cycles and to study the effects of oil sulfur and metallic-ash constituents on the particle chemical characteristics, respectively. Details of the surface oxygenated functional groups and carbon chemical state on the particle surface were analyzed by XPS, while the FTIR was employed to characterize the possible functional groups in the bulk particle samples and the bonding patterns of the sulfur element. The effects on the particle morphology and elemental compositions were analyzed by SEM-EDS. Results show that the lubricating oil could shorten the ignition-delay phase combustion effectively, for instance, by 20% when 1wt% oil is burned along with diesel. Furthermore, more oxygenated surface functional groups and relatively more sp3 hybridization carbon shows up in the oil-derived particles. The sulfur element in the oil increases the oxygenated functional groups and lowers the aliphatic C H group by forming –SH radical. On the contrary, the metallic-ash fraction reduces the amount of oxygenated functional groups because the inorganic sulfates/phosphates occupy some oxygen atoms during the combustion reaction. Both the sulfur and ash tend to generate more un-substituted and meta-disubstituted benzene instead of the mono-disubstituted benzene structure, which is popular in diesel fuel-related particles mainly. Last but not the least, the sulfur and ash content significantly increase the concentration of the sulfates and phosphates of Iron, Calcium, and Zinc in the particles. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to test the hypothesis that the pulp medication ferric sulphate (FS) may remain on primary dentin, affecting its microchemical structure and the bond strength of adhesives to primary dentin. Materials and Methods: The effects of FS and pre-bonding conditioning (37% phosphoric acid [PA] for 15 s or a self-etching primer, with or without the use of 2% chlorhexidine [CHX]) on FS-treated primary dentin were characterized using optical microscopy with Masson's and Perls' stains, variable-pressure SEM/energy-dispersive x-ray spectroscopy (VP-SEM/EDS), Fourier transform infrared spectroscopy (FT-IR), and x-ray diffraction. Ferric sulphate was applied for 30 s or 1 h for microchemical analysis. The adhesive interface and the bond strength were studied by VP-SEM/EDS and the μTBS test (1 mm² bars, crosshead speed 0.5 mm/min), respectively. The study groups were: etch-and-rinse (E&R, Excite) adhesive (group 1); FS+E&R (group 2); FS+CHX+E&R (group 3); self-etching (SE, Adper Scotchbond) adhesive (group 4); FS+SE (group 5); FS+CHX+SE (group 6). Results: Ferric sulphate application produced demineralization, gypsum formation, and adsorption of Fe on the dentin surface, and it modified the collagen structure of primary dentin. There were no effects of FS on bond strength of the tested etch-and-rinse adhesive system. FS slightly reduced the bond strength between the primary dentin and the SE adhesive, and the values were not restored by CHX (group 4 = 17.58 ± 5.52 MPa > group 5 = 14.26 ± 7.08 MPa = group 6 = 13.96 ± 4.87 MPa). Conclusions: Ferric sulphate alters the microchemical structure of primary dentin and can impair the adhesive strength of some self-etching adhesives. [ABSTRACT FROM AUTHOR]

In this study, minerals required for the growth and aflatoxin production of A. flavus were determined. Then, the effectiveness of some chelating agents such as citric acid, phytic acid and ethylenediaminetetraacetic acid (EDTA) in preventing mold growth and toxin production was investigated in a fig-based medium and in two synthetic media, called Czapek-dox agar (CZA) and potato dextrose agar (PDA). A. flavus did not grow in CZA without sodium nitrate during 6-day incubation at 30 °C. The absence of the other components (magnesium sulfate, iron sulfate, potassium chloride and potassium phosphate) did not significantly (p>0.05) affect the growth of the mold. However, the mold produced significantly (p<0.05) higher amounts of aflatoxins in the media without magnesium sulfate and iron sulfate. A. flavus grew faster on fig-based medium and produced higher amounts of aflatoxins in PDA. In all media tested in this study, EDTA was found to be more effective than the other agents in controlling the growth of A. flavus. It was also effective in inhibiting the production of aflatoxins. It was determined that 1.75 mM EDTA reduced aflatoxin production up to 97% in PDA. Citric and phytic acids could inhibit the growth of the mold only in PDA. All chelating agent reduced aflatoxin production over 90% in fig-based medium. [ABSTRACT FROM AUTHOR]

This study reports on the effect of inoculum history, growth substrates, and yeast extract on sodium chloride tolerance of Sulfobacillus thermosulfidooxidans DSM 9293T. The concentrations of NaCl for complete inhibition of Fe2+ oxidation by cells initially grown with ferrous iron sulfate, or tetrathionate, or pyrite as energy sources were 525 mM, 725 mM, and 800 mM, respectively. Noticeably, regardless of NaCl concentrations, oxygen consumption rates of S. thermosulfidooxidans with 20 mM tetrathionate were higher than with 50 mM FeSO 4. NaCl concentrations of higher than 400 mM strongly inhibited the iron respiration of S. thermosulfidooxidans. In contrast, the presence of NaCl was shown to stimulate tetrathionate oxidation. This trend was especially pronounced in NaCl-adapted cells where respiration rates at 200 mM NaCl were threefold of those in the absence of NaCl. In NaCl-adapted cultures greater respiration rates for tetrathionate were observed than in non-NaCl-adapted cultures, especially at concentrations ≥ 200 mM NaCl. At concentrations of ≤ 200 mM NaCl, cell growth and iron oxidation were enhanced with the addition of increasing concentrations of yeast extract. Thus, cell numbers in cultures with 0.05% yeast extract were ∼5 times higher than without yeast extract addition. At NaCl concentration as high as 400 mM, however, iron oxidation rates improved compared to control assays without yeast extract, but there was no clear dependence on yeast extract concentrations. The initial growth of bacteria with and without yeast extract in the presence of different NaCl concentrations was shown to impact leaching of copper from chalcopyrite. Copper dissolution was enhanced in the presence of 200 mM NaCl and absence of yeast extract, while the addition of 0.02% yeast extract was shown to promote copper solubilization in the presence of 500 mM NaCl. [ABSTRACT FROM AUTHOR]

The aim of the study was to assess the concentration of salinity indicators in the Bystrzyca River in the city of Lublin, located in south-eastern Poland. The studies on the quality of water from the river were carried out from November 2018 to June 2019, i.e. in winter and spring. The water samples for analysis were taken from 9 measurement points located on the river under bridges and at high traffic roads. In total, 8 series of analyses were carried out, during which 72 water samples from the Bystrzyca River were examined. The samples were analyzed in terms of: water temperature, pH value, conductivity as well as concentration of chlorides and sulfates. An increase in both the specific conductivity and chloride and sulfate concentrations was found in the water from the Bystrzyca River during the period of low air temperatures (≤0o C), i.e. in December 2018 and January 2019. This may be a result of winter road maintenance procedures, i.e. by using salts for their defrosting. At the same time, an increase in the conductivity value and the concentration of chlorides and sulfates was observed with the course of the river, which indicates that the pollution generated in the city of Lublin has a negative impact on the water quality in the studied river. The salinity of the Bystrzyca River was greatly affected by the operation of the municipal wastewater treatment plant in Hajdów, especially by the use of coagulants: polyglycol chloride (PAX 18) and iron sulfate (PIX 113). [ABSTRACT FROM AUTHOR]

Vibrational spectroscopy has been used to characterize the three uncommon complex iron sulfates clairite, (NH4)2Fe3(SO4)4(OH)3 3H2O, metavoltine, Na6K2Fe2+Fe3+6(SO4)12O2·18H2O, and voltaite, K2Fe2+5Fe3+3Al(SO4)12 18H2O. The investigated specimens were formed at the burning coal dump Anna I (Alsdorf, Germany) due to alteration processes connected with the subsurface thermal activity. It is found that all three minerals display complex Raman spectra with an extensive proliferation of bands attributed to the sulfate vibrational modes. Both clairite and metavoltine show extraordinary strong Raman bands in the low‐wavenumber region, which can be attributed to the FeO stretching modes. Clairite and metavoltine show a very similar spectral shape; it can be concluded that both minerals can exhibit a similar crystal structure. In comparison, voltaite represents a different structural type; therefore, a distinct Raman spectrum is observed. [ABSTRACT FROM AUTHOR]

Arctic fjord sediments of Svalbard receive terrestrial material from glacial runoff and organic matter from marine primary productivity. Organic carbon mineralization proceeds primarily through sulfate and iron reduction in the fjord sediment. The ongoing retreat of glaciers in the high Arctic is altering the input of glacial material to the fjords, with unknown consequences for the iron and sulfur cycles in the fjord sediments. We measured sulfate reduction rates in sediment cores and analyzed porewater geochemistry, then compared these results to long-term sediment incubations to determine the rates of iron reduction and sulfide oxidation in three glacially influenced fjords on the west coast of Spitsbergen, Svalbard. Despite an abundance of glacially-sourced Fe(III)-oxide minerals, active sulfate reduction took place throughout the sediment. Analyses of the sulfur and oxygen isotopic composition of porewater sulfate and sulfate concentrations suggest that sulfide produced from biological sulfate reduction is reoxidized to sulfate. Long-term sediment incubations indicated sulfide oxidation at all three stations. The rate of sulfide oxidation was controlled by both the rate of sulfate reduction and the quantity and reactivity of Fe(III)-oxides. In our experimental incubations, we detected a decrease in Fe(III) content of the 0.5 M HCl and ascorbate-extractable fractions, but not in the 6 M HCl fraction, indicating that the highly reactive Fe(III) fraction is utilized by microorganisms and serves as the oxidant for sulfide oxidation. Our results show that sulfide oxidation in glacially-influenced fjord sediments is a wide-spread geochemical process. Further warming will drive glacial retreat onto land, where sediment-laden glacial meltwater will be altered during flow through proglacial streams and lakes before entering the marine environment. Fjord sediments will likely become more sulfidic, as glaciers deliver less particulate, highly-reactive metal oxides to the marine environment. [ABSTRACT FROM AUTHOR]

This study presents a cost-effective method of enhancing the electrical conductivity and washing durability of bacterial cellulose (BC)-polyaniline (PANI) membrane by the addition of metal salt. In this study, two types of metal salts were tested: copper (II) sulfate and iron (II) sulfate. The optimal condition to produce BC-PANI-metal salt membranes was 0.05% (w/v) of copper (II) sulfate (copper salt). X-ray diffraction analysis showed that the crystallinity of BC-PANI increased after adding copper salt. According to the increased degree of crystallinity, the polymer chain structure of BC-PANI-copper salt (BC-PANI-Cu) was more organized than that of BC-PANI, as confirmed by scanning electron microscopy. In addition, this ordered structure of BC-PANI-Cu indicated enhanced electrical conductivity. Moreover, the addition of copper salt improved the electrical conductivity of BC-PANI to a level about 3.8 times higher than that of BC-PANI produced without metal salt, and it retained about 40% of its original electrical conductivity after three washing cycles. From the results, the addition of copper salt improved both the electrical conductivity and washing durability of the BC-PANI membrane. [ABSTRACT FROM AUTHOR]

Take-all caused by the soil-born fungi Gaeumannomyces graminis (Sacc) Arx & Olivier is an important crown and root rot diseases of wheat throughout the world. Biological control and plant nutrition management are two effective methods for the control of this disease. In this study, effect of plant nutrition was investigated on improvement of wheat growth and suppression of the Take-all disease. For this purpose, the effect of iron sulfate, copper sulfate and zinc sulfate on Take-all disease of wheat was studies on the basis of infected roots and production of shoot dry weight. The obtained results revealed that the experimental soil was slightly alkaline. The soil contained adequate amounts of nitrogen and zinc, but was poor in availability of iron, cupper and mild deficit in phosphorus. In order to investigate the effect of the nutrients on growth and severity of the disease, four levels (0, 2.5, 5.0 and 10 mg/kg soil) of micronutrients were used. Iron had greatest effect on suppression of Take-all disease among applied micronutrients. The infected roots decreased from 89 to 53% and abolished symptoms on wheat crown up to nine times with the application if iron. In addition, iron increased the dry weight of aerial parts of wheat from 0.78 to 1.3 g per plant. The effects of zinc and copper fertilizers on disease suppression on wheat was less than that of iron with decreased infected roots to 57 and 64%, respectively. Overall, increase in the amount of iron sulfate decreased the severity of the disease and enhanced biomass of aerial parts in infected wheat plants. [ABSTRACT FROM AUTHOR]

Development of an appropriate bioremediation strategy for acid mine drainage (AMD) impacted environment is imperative for sustainable mining but remained critically challenged due to the paucity of knowledge on desired microbiological factors and their nutrient requirements. The present study was conducted to utilize the potential of an anaerobic, acid-tolerant, Fe3+ and SO42− reducing microbial consortium for in situ remediation of highly acidic (pH 3.21), SO42− rich (6285 mg/L) mine drainage impacted soil (AIS). A microbial consortium enriched from AMD system and composed of Clostridiales and Bacillales members was characterized and tested for in situ application through microcosms. A combination of bioaugmentation (enriched consortium) and biostimulation (cellulose) allowed 97% reduction in dissolved sulfate and rise in pH up to 7.5. 16S rRNA gene-based amplicon sequencing confirmed that although the bioaugmented community could survive in AIS, availability of carbon source was necessary for superior iron- and sulfate- reduction. Quantitative PCR of dsrB gene confirmed the role of carbon source in boosting the SO42− reduction activities of sulfate reducers. This study demonstrated that native AIS harbored limited catabolic activities required for the remediation but addition of catabolically active microbial populations along with necessary carbon and energy source facilitate the bioremediation of AIS. [ABSTRACT FROM AUTHOR]

The mode of action of iron(III) uptake from sulfate solutions by the commercial extractant CYANEX®272, bis(2,4,4-trimethylpentyl)phosphinic acid, has been studied using conventional solvent extraction methods, together with 31P{1 H} NMR spectroscopy, electrospray ionisation mass spectrometry, and DFT calculations that have not previously been used to analyse the content of the ISOPAR M water-immiscible phase. The maximum Fe-loading recorded was 177% of the theoretical maximum, based on the formation of an Fe(III) complex [Fe(L)3] with a 1:3 molar ratio of Fe to phosphinate (L). Inductively coupled plasma optical emission spectroscopy (ICP-OES) indicates that sulfate or hydrogen sulfate ions are co-extracted in a 1:2 molar ratio with iron across the whole of the Fe-loading range, which helps to account for the loadings being greater than 100% of the theoretical value. 31P{1 H} NMR spectroscopy indicates that the limiting factor in Fe-loading is the availability of uncomplexed CYANEX®272 (sulfate is present in large excess). In contrast to the behaviour of Co(II) and Zn(II) extraction by CYANEX®272, there is no evidence for the formation of polymeric Fe(III) complexes and highly viscous solutions at high metal loadings. The identity of the extracted species is likely to be a polynuclear Fe(III) sulfate complex. [ABSTRACT FROM AUTHOR]

Dissimilatory iron reduction and sulfate reduction are the most important processes for anaerobic mineralization of organic carbon in marine sediments. The thermodynamics and kinetics of microbial Fe(III) reduction depend on the characteristics of the Fe(III) minerals, which influence the potential of Fe(III)-reducers to compete with sulfate-reducers for common organic substrates. In the present study, we tested different methods to quantify and characterize microbially reducible Fe(III) in sediments from a transect in Kongsfjorden, Svalbard, using different standard sequential endpoint extractions and time-course extractions with either ascorbate or a Fe(III)-reducing microbial culture. Similar trends of increasing 'reactive Fe' content of the sediment along the fjord transect were found using the different extraction methods. However, the total amount of 'reactive Fe' extracted differed between the methods, due to different Fe dissolution mechanisms and different targeted Fe fractions. Time-course extractions additionally provided information on the reactivity and heterogeneity of the extracted Fe(III) minerals, which also impact the favorability for microbial reduction. Our results show which fractions of the existing Fe extraction protocols should be considered 'reactive' in the sense of being favorable for microbial Fe(III) reduction, which is important in studies on early diagenesis in marine sediments. [ABSTRACT FROM AUTHOR]

The effect of nickel, cobalt, and iron sulfates' additives in the alkali-silicate electrolyte for microarc oxidation on the element composition and electrochemical behavior of MAO-coatings formed on titanium has been studied. It has been established that these additives were incorporated into an oxide layer. The increase of the content of these components in the electrolyte resulted in the decrease of their content (along with silicon) in the coating and the increase of the titanium content. This dependence can be related to the MAO process mechanism specifics and, first of all, to changes in temperature–time characteristics of microarc discharges. [ABSTRACT FROM AUTHOR]

• The combination of Fe2+/Fe3+ sulfate was used as selective depressant for the flotation separation of fluorite and calcite. • Ferrous and ferric species were in-situ generated on calcite surface to hinder the adsorption of NaOL. • Fluorite concentrate with CaF 2 grade of 80.29 % and recovery of 90.79 % was obtained using 1:1 mixed minerals. It is known that the flotation separation of fluorite/calcite is extremely difficult because of their similar surface features. In this research, the combination of FeSO 4 ·7H 2 O and Fe 2 (SO 4) 3 (FF) as depressant for possible flotation separation of calcite/fluorite was systematically investigated, with sodium oleate (NaOL) as collector. Besides large gap between mono-mineral flotation results of fluorite and calcite, even for 1:1 mixed sample, CaF 2 grade of 80.29 % and CaF 2 recovery of 90.79 % of fluorite concentrate can be achieved with FeSO 4 ·7H 2 O (300 mg/L) and Fe 2 (SO 4) 3 (150 mg/L) used as combined depressant and NaOL (40 mg/L) as collector at pH = 6. In addition to the quantitative micro-flotation results on mono-mineral and artificially mixed sample, SEM-EDS, contact angle measurement, zeta potential measurement, FTIR and XPS analyses, as well as collector adsorption experiment, were carried out to clarify the selective inhibition mechanism. Characterizations confirmed that, under interaction with iron sulfates (FF), ferrous hydroxide, ferric hydroxide, hydroxyl iron oxide and green rust were in-suit generated on calcite surface due to the presence of the hydrolysis of OH− and CO 3 2− on calcite surface, while such Fe-related components were barely discernible on fluorite surface. These different adsorption features for Fe (II) and Fe (III) species on mineral surfaces exactly hindered the complexation of NaOL on calcite surface, while maintained the adsorption of collector on fluorite surface, thereby to realize the selective separation of fluorite from calcite. [ABSTRACT FROM AUTHOR]

This paper presents evidence on the possible impact of aerobic and anaerobic microbiological processes on uranium migration in upper aquifers polluted by sulfates and nitrates at the Novosibirsk chemical concentrate plant (PAO NCCP). Uranium can be immobilized in local areas with high contents of organic substances, and the most important microbiological process is a decrease in redox potential owing to aerobic respiration, which can be followed under anaerobic conditions by redox-dependent uranium reduction in areas with negative Eh values. Moreover, in the presence of sufficient amounts of sulfate ions, further anaerobic processes of microbial sulfate and iron reduction result in the formation of iron sulfide, which serves as an antioxidant buffer in the case of oxygen infiltration into the sediment and transforms to molecular sulfur or sulfate preventing uranium oxidation. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Particle size reduction of FeSO 4 (iron(II) sulfate, IS) from micron to nano size was achieved by a combination of hot-melt extrusion (HME) processing and the input of Span 80, Tween 80, and poly(ethylene glycol) (PEG) 6000. Conveying, kneading, and extruding steps of the HME process and a decrease in the surface tension by surfactants were introduced to produce FeSO 4 nanoparticles (NPs) in an aqueous environment. The FeSO 4 -based NPs (ISNPs) in the dispersion were composed of FeSO 4 , Span 80, Tween 80, and PEG 6000 and displayed a hydrodynamic size of 350–400 nm (5–50 mg/mL ISNPs concentration range) and a spherical shape. Considering the feeding ratio of FeSO 4 (20%, w/w) used for preparing the ISNPs, FeSO 4 appears to be wrapped by Span 80, Tween 80, and PEG 6000 according to the results of X-ray photoelectron spectroscopy (XPS) analysis. ISNPs exhibited different thermodynamic properties from those of FeSO 4 itself. In colon adenocarcinoma (Caco-2) cells, the ISNPs group exhibited enhanced antiproliferation and apoptosis potentials compared to the FeSO 4 group (p < 0.05). Histological staining data of a dissected intestine after oral administration of ISNPs suggest the absence of severe intestinal toxicities compared to the control (no treatment) group. All of these results imply the feasibility of the use of the developed ISNPs for the treatment of colon cancers with oral administration. [ABSTRACT FROM AUTHOR]

Online spectrophotometric method was employed to monitor the degradation of Reactive Dark Blue B-2GLN (RDB B-2GLN) solution with Fenton oxidation process. The effect of initial FeSO4 concentration, initial H2O2 concentration, pH value, and initial dye concentration on chroma removal has been studied. The kinetic mechanics was estimated. The results show that: under the preparation conditions of the optimum dosage of H2O2 2.635 mM, pH 2.7, Fe2+ dosage 0.0696 mM, and the initial dye concentration 16 mg/L, the color removal rate of Reactive Dark Blue B-2GLN is about 85.04% after 300 s. The intrinsic reaction rate constant of ·OH with RDB B-2GLN in aqueous solution is 2.62 × 1011 M–1 s–1. The molecule structure of RDB B-2GLN is decomposed and not mineralized completely by Fenton’s reagent (300 s). The intermediate product and possible degradation mechanism of RDB B-2GLN is predicted by GC-MS analysis. Online spectrophotometric method is an accurate, quick, and feasible technique to monitor color removal rate of RDB B-2GLN in Fenton process. [ABSTRACT FROM AUTHOR]

Iron-sulfur (Fe-S) clusters are ubiquit1ous cofactors present in all domains of life. The chemistries catalyzed by these inorganic cofactors are diverse and their associated enzymes are involved in many cellular processes. Despite the wide range of structures reported for Fe-S clusters inserted into proteins, the biological synthesis of all Fe-S clusters starts with the assembly of simple units of 2Fe-2S and 4Fe-4S clusters. Several systems have been associated with the formation of Fe-S clusters in bacteria with varying phylogenetic origins and number of biosynthetic and regulatory components. All systems, however, construct Fe-S clusters through a similar biosynthetic scheme involving three main steps: (1) sulfur activation by a cysteine desulfurase, (2) cluster assembly by a scaffold protein, and (3) guided delivery of Fe-S units to either final acceptors or biosynthetic enzymes involved in the formation of complex metalloclusters. Another unifying feature on the biological formation of Fe-S clusters in bacteria is that these systems are tightly regulated by a network of protein interactions. Thus, the formation of transient protein complexes among biosynthetic components allows for the direct transfer of reactive sulfur and Fe-S intermediates preventing oxygen damage and reactions with nonphysiological targets. Recent studies revealed the importance of reciprocal signature sequence motifs that enable specific protein-protein interactions and consequently guide the transactions between physiological donors and acceptors. Such findings provide insights into strategies used by bacteria to regulate the flow of reactive intermediates and provide protein barcodes to uncover yet-unidentified cellular components involved in Fe-S metabolism. [ABSTRACT FROM AUTHOR]

Among the methods used in the literature for the synthesizing of nano zero valent iron (nZVI), borohydride is the most commonly used method; it is seen that different variables are used together. In this study, optimum nano zero valent iron (nZVI) synthesizing method using borohydride method has been modified by using multiple optimization method in terms of both particle size and zeta potential. Selected independent variables are selected as iron sulfate concentration, ethanol ratio, and flow rate of borohydride solution. With the optimum synthesis method determined, the lowest particle size was obtained as 70 nm only when the particle size was taken into consideration, whereas 88.2 nm nZVI could be produced when both the particle size and the zeta potential were taken into consideration. In addition, the removal of DDT, which is the most commonly used persistent organic pollutant pesticides in the world, was investigated by nZVI synthesized. Different initial DDT concentration was investigated by expressing oxidation reduction potential (ORP) difference, removal rates, and oxidation byproducts. When DDD and DDE concentrations are considered, it is found that DDT is more likely to oxidize in DDD in all studied initial DDT concentrations. Removal rate was higher than 80% with initial concentrations lower than 125 μg/L, which is a high concentration that could be found in surface waters. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate the genotoxic effects of iron sulfate on mice through the assessment of chromosomal aberration, mitotic activity and DNA fragmentation by RAPD-PCR, as well as screening for the possible ameliorating effect of extra-virgin olive oil (EVOO) against iron sulfate genotoxicity. Sixty-four swiss albino male mice (Mus musculus), weighing from 25 to 35 gm were used in the study. Forty mice were used in the acute study for 24 and 48 hrs and twenty-four were used for chronic treatment (six weeks). In both acute studies, the mice were divided into five groups, the first group acts as a control without any treatment. The second group received 75 μl EVOO on a diet for one day before samples collection. The third group received 61.2 mg/kg b.wt iron in a diet which represents 1/5 of its oral LD50, the fourth group received the same previous doses of EVOO and iron sulfate at the same time. The fifth group received EVOO as a pre-treatment for one week then received iron sulfate with the previous dose for 24 hrs. Four similar experimental groups were also used for chronic study with 15.3 mg/kg b.wt iron sulfate in the diet which represents 1/20 of its oral LD50 and the same dose of EVOO as a co-treatment. Iron sulfate in mice ration was able to produce structural chromosomal aberration in acute treatment and structural and numerical in chronic treatment, lowering mitotic activity and induced DNA fragmentation (RAPD fragments) at both treatments. EVOO as a co-treatment or pre-treatment leads to decrease in chromosomal aberration especially chromatid breaks, chromatid deletion and fragments in acute treatment. In general, EVOO as a co-treatment showed a significant role in lowering Iron sulfate genotoxicity in acute treatments. [ABSTRACT FROM AUTHOR]

Iron cations are essential for the high activity of nickel and cobalt‐based (oxy)hydroxides for the oxygen evolution reaction, but the role of iron in the catalytic mechanism remains under active investigation. Operando X‐ray absorption spectroscopy and density functional theory calculations are used to demonstrate partial Fe oxidation and a shortening of the Fe−O bond length during oxygen evolution on Co(Fe)OxHy. Cobalt oxidation during oxygen evolution is only observed in the absence of iron. These results demonstrate a different mechanism for water oxidation in the presence and absence of iron and support the hypothesis that oxidized iron species are involved in water‐oxidation catalysis on Co(Fe)OxHy. [ABSTRACT FROM AUTHOR]

Abstract: In this study, a fast and inexpensive approach is introduced to assist stabilization of polyacrylonitrile (PAN) fibers by adding ammonium iron(II) sulfate in coagulation bath. Effects of chemical treatment on stabilization process and structural evolution of fibers are studied using calorimetric, infrared, and X‐ray techniques. A stepwise infrared study confirms the assisted cyclization reaction, and an X‐ray analysis reveals a significant improvement in crystallinity and orientation of polymer chains which lead to an increase in tensile strength and modulus of PAN fibers. Differential scanning calorimetry results show 13 °C reductions in peak temperature of the stabilization reaction which means a sign of chemical activation at lower temperature by adding sulfate ions. Quantification of IR spectra shows a 7% increase in extent of reaction of chemically treated fibers and higher degree of conjugation compared with untreated and post‐treated fibers. Finally, mechanical properties of chemically treated fibers are improved due to an increase in size and orientation of polymer chains after chemical treatment in the coagulation bath. Compared to control and post‐treated PAN fibers, thermochemical properties of presented fibers are improved due to chemically assisted stabilization, and as a consequence, energy consumption of the stabilization step will be reduced by a simple and facile treatment. [ABSTRACT FROM AUTHOR]

Abstract: Exploring materials with regulated local structures and understanding how the atomic motifs govern the reactivity and durability of catalysts are a critical challenge for designing advanced catalysts. Herein we report the tuning of the local atomic structure of nickel–iron layered double hydroxides (NiFe‐LDHs) by partially substituting Ni2+ with Fe2+ to introduce Fe‐O‐Fe moieties. These Fe2+‐containing NiFe‐LDHs exhibit enhanced oxygen evolution reaction (OER) activity with an ultralow overpotential of 195 mV at the current density of 10 mA cm−2, which is among the best OER catalytic performance to date. In‐situ X‐ray absorption, Raman, and electrochemical analysis jointly reveal that the Fe‐O‐Fe motifs could stabilize high‐valent metal sites at low overpotentials, thereby enhancing the OER activity. These results reveal the importance of tuning the local atomic structure for designing high efficiency electrocatalysts. [ABSTRACT FROM AUTHOR]

Ferric sulfate is a simple and commercially available solid catalyst and demonstrated to be able to catalyze terpenic alcohols esterification with acetic acid, achieving high conversion and ester selectivity. This process is an attractive option to the enzymatic or acid homogenous processes commonly used to synthesize esters. The undesirable steps of neutralizing of the products are avoided. A study of the activity of hydrated Fe2(SO4)3 demonstrated that although the efficiency of the catalyst is directly linked to the ability of the FeIII cations to generate H3O+ ions, the solid catalyst plays also a key role on the esterification process. We assessed the effects of the main reaction variables such as reactants proportion, temperature, and catalyst concentration. Different terpenic alcohols such as β‐citronellol, geraniol, nerol, linalool, α‐terpineol and borneol were esterified in the presence of Fe2(SO4)3 catalyst. The Fe2(SO4)3 catalyst was easily recovered and reused. A simple method for the synthesis of fragrances is described using renewable raw material derivatives (i. e., terpenic alcohols) and acetic acid in solid ferric sulfate‐catalyzed reactions. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this study is to evaluate the role of encapsulation pH and iron source on the anchorage mode and performance of iron oxide-encapsulated aluminium pigments.Design/methodology/approach The coloured waterborne aluminium pigments were prepared at pH 5-7.5 by using FeSO4 and FeCl3 as iron source. The anchorage mode of iron oxides on aluminium was characterized using optical microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction. Furthermore, the pigmentary performance was characterized through anticorrosion test and multi-angle spectroscopy.Findings Diaspore and boehmite could form from H2O2 oxidizing aluminium. Both low pH and FeSO4 systems are beneficial for diaspore, inducing green rust anchor on the aluminium to form goethite. Either in FeSO4 or FeCl3 system, slightly high pH is beneficial for the formation of boehmite, which occurred together with ferrihydrite to form denser coating with yellowness and excellent anticorrosion property. At pH above 7, the formation of dendritic iron oxide is detrimental to the anticorrosion property and the glossiness.Research limitations/implications Only FeSO4·7H2O and FeCl3·6H2O as iron sources were explored.Practical implications The investigation results provide theoretical basis to obtain excellent chromatic waterborne aluminium pigments.Originality/value The method for investigation of encapsulation mechanism by surveying the structure of iron oxides on aluminium, which varies with the pH of the system and iron sources, is novel. [ABSTRACT FROM AUTHOR]

Abstract: Supercapacitors with fast charge/discharge rate and long cycling stability (>50 000 cycles) are attractive for energy storage and mobile power supply. In this paper, a facile strategy is developed to fabricate an Fe2O3/FeS‐decorated N, S‐codoped hierarchical porous carbon hybrid. Its microstructure and compositions can be readily controlled through adjusting the hydrothermal reaction between waxberry and iron sulfate. The constructed supercapacitors with the as‐prepared carbon materials from this reaction are able to exhibit outstanding capacitive performance with a superfast charge/discharge rate (<1 s), ultralong cycle life (>50 000 cycles, 80 A g−1), ultrahigh volumetric capacitance (1320.4 F cm−3, 0.1 A g−1), and high energy density (100.9 W h kg−1, 221.9 W h L−1). The outstanding performance makes it one of the best biomass‐derived supercapacitors. The superior capacitive behavior is likely to arise from the N and S codoping on the surface/edge/skeleton of the carbon microspheres and nanosheet composites coupled with the fast redox reaction of Fe2O3/FeS. Overall, this research presents a new avenue for developing the next generation of sustainable high‐performance energy storage device. [ABSTRACT FROM AUTHOR]