Increasing Fe Content Research Articles

Alkaline and acidic soil constraints on iron accumulation by Rice cultivars in relation to several physio-biochemical parameters

Agricultural production is severely limited by an iron deficiency. Alkaline soils increase iron deficiency in rice crops, consequently leading to nutrient deficiencies in humans. Adding iron to rice enhances both its elemental composition and the nutritional value it offers humans through the food chain. The purpose of the current pot experiment was to investigate the impact of Fe treatment in alkaline (pH 7.5) and acidic (pH 5.5) soils to introduce iron-rich rice. Iron was applied to the plants in the soil in the form of an aqueous solution of FeSO4 with five different concentrations (100, 200, 300, 400, and 500 mM). The results obtained from the current study demonstrated a significant increase in Fe content in Oryza sativa with the application of iron in both alkaline and acidic pH soils. Specifically, Basmati-515, one of the rice cultivars tested, exhibited a notable 13% increase in iron total accumulation per plant and an 11% increase in root-to-shoot ratio in acidic soil. In contrast to Basmati-198, which demonstrated maximum response in alkaline soil, Basmati-515 exhibited notable increases in all parameters, including a 31% increase in dry weight, 16% increase in total chlorophyll content, an 11% increase in CAT (catalase) activity, 7% increase in APX (ascorbate peroxidase) activity, 26% increase in POD (peroxidase) activity, and a remarkable 92% increase in SOD (superoxide dismutase) in acidic soil. In alkaline soil, Basmati-198 exhibited respective decreases of 40% and 39% in MDA and H2O2 content, whereas Basmati-515 demonstrated a more significant decrease of 50% and 67% in MDA and H2O2 in acidic soil. These results emphasize the potential for targeted soil management strategies to improve iron nutrition and address iron deficiency in agricultural systems. By considering soil conditions, it is possible to enhance iron content and promote its availability in alkaline and acidic soils, ultimately contributing to improved crop nutrition and human health.

Effect of Fe on the oxidation, sulfidation and carburization behaviors of alloys in CO2 containing SO2

The effect of Fe on the oxidation, sulfidation and carburization behaviors of alloys in CO2 containing SO2 at 1000 ℃ was investigated using multiple evaluation methods, including first-principles, molecular dynamics simulation, high-temperature corrosion experiment and thermodynamic analysis. The adsorption capacity of both gas molecules on FeCr alloy surface was stronger than that on NiCr alloy surface. The molar content of O, C and S atoms in Fe-25Ni-22Cr alloy was higher than that in Ni-25Fe-22Cr alloy. The increase of Fe content promoted the reactions between alloy elements and O, C, S atoms, which caused serious corrosion of Fe-Ni-Cr alloys.

The effect of Fe content on crystal phase and mechanical properties of 6061 aluminium alloy

In order to eliminate the adverse effects of impurity element Fe in aluminium alloy, the effects of Fe content on the microstructures and mechanical properties of 6061 aluminium alloy were studied utilizing scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and tensile testing machine. The results show that Fe exists mainly in α-AlFeSi and β-AlFeSi phases. Elemental Fe promotes the generation of fishbone shaped α-AlFeSi phase, while the percentage of needle shaped β-AlFeSi phase gradually decreases. After homogenizing annealing, the Mg2Si phase has been redissolved, and a large amount of Si element exists in the aluminium matrix. With the increase of Fe and Si content, β→α phase transition has been completed, and the fishbone α-AlFeSi phase accumulates at the grain boundary. After the extrusion forming process, the morphology of the α-Al12(MnFe)3Si phase changes from fishbone to granular, and the bulk deposition of α-Al12(MnFe)3Si improves the strength of 6061 aluminium alloy.

Influence of Fe on Crystallization Behaviour and Electrical Conductivity of V2O5 ⋅ MoO3 ⋅ CdO ⋅ ZnO Glass Nanocomposite

AbstractThe effect of varying iron content on the crystallization behavior and electrical conductivity mechanism of glass nanocomposite based on the system xFe ⋅ (1‐x) ⋅ (0.3 V2O5 ⋅ 0.2MoO3 ⋅ 0.4CdO ⋅ 0.1ZnO) (x=0.0, 0.05 and 0.1) was investigated by differential scanning calorimetry (DSC), Fourier transforms infrared (FTIR), X‐ray diffraction (XRD), and field emission‐scanning electron microscopy (FESEM). Different crystal phases and the average size of the developed nanocrystallites in the as‐prepared samples have been obtained from the XRD diffraction data. The size of estimated nanocrystallites increases up to Fe (x) content 0.05, after which the size of nanocrystallites decreases as the Fe content in the compositions increases. FESEM micrographs confirm the formation of plate‐like and dendrite nano crystallites throughout the glass matrix. Energy‐dispersive X‐ray spectroscopy (EDX) mapping analysis shows the weight percentage of each constituent element. The dc activation energy (Eσ), as well as activation energy (EH) for hopping frequency of as‐prepared samples, gradually decreases with increasing Fe content whereas AC and DC conductivity gradually increased.

Modulation of the magnetization and Gilbert damping in Heusler-alloy Co3–xFexAl thin films

The saturated magnetization (mtot) and the Gilbert damping constant (α) are the two key factors that determine the critical current density of the magnetization reversal in the spin-transfer-torque magnetic memory devices. Here, this study demonstrates the efficient modulation of these two parameters by tunning the composition of the Heusler Co3–xFexAl thin films, utilizing the x-ray magnetic circular dichroism technique and ferromagnetic resonance measurements. With the increase in Fe concentration, the mtot shows a downward trend mainly resulting from the decrease in Fe local magnetic moment instead of Co. On the other hand, the ultralow α decreases from 0.004 to 0.0012. This has been attributed to the reduction in the spin–orbit coupling, which is corroborated by the decrease in the orbit-to-spin moment ratio. Our findings add a building block for the Heusler compounds with tunable Gilbert damping and appropriate magnetization and show great potential in spintronic applications.

Thermodynamic Calculation of 2618 High Performance Aluminum Alloy

The thermodynamic-related physical parameters, precipitation amount of equilibrium phase, and initial precipitation temperature of Al-(1.9–2.5) Cu-(1.2–1.8) Mg-(0.9–1.5) Fe-(0.9–1.5) Ni alloy were simulated by using the thermodynamic simulation software JMat-Pro. The results show that with the change of element content, the liquidus temperature is in the range of 641.92–638 °C. The precipitation transition temperature of the eutectic phase with a low melting point ranges from 515 °C to 517.25 °C. The solidus temperature is closely related to Cu/Mg. The dendrite spacing decreases with the increase of Mg and Fe (Ni) contents, among which Mg has the greatest influence, followed by Fe (Ni) and Cu. The partial molar Gibbs free energy of Cu, Mg, Fe, and Ni is negative. The activity of Mg increases with the decrease in temperature, and the maximum activity is 0.10189, while the activities of Cu, Fe, and Ni are close to 0. The initial precipitation temperatures of S(Al2CuMg) and Al9FeNi phases are 424–450 °C and 635.4–643.01 °C, respectively. The initial precipitation temperature of the Al9FeNi phase decreases with the increase of Cu and Mg contents, while it increases with the increase of Fe (Ni) contents. With the increase of Cu and Mg contents, the initial precipitation temperature of S(Al2CuMg) increases and decreases with the increase of Fe (Ni) contents. The precipitation amount of S(Al2CuMg) mainly depends on the content and ratio of Cu and Mg, while that of Al9FeNi increases with the increase of Fe and Ni elements in the same proportion.

Pressure-induced phase transitions in Ni-bearing ferrosilite (Ni-En31Fs65)

Abstract Orthopyroxene is an abundant mineral in subducting slabs. Studying its phase transitions at high pressure is important to the understanding of mineralogy of subducting slabs in the deep Earth. Synchrotron-based single-crystal X-ray diffraction experiments were conducted on a synthetic Ni-bearing ferrosilite (Ni-En31Fs65) at pressures up to 33.8 GPa. Three phase transitions were observed at 12.1(6), 15.6(6), and 31.3(25) GPa. The first two phase transitions in Ni-En31Fs65 resemble the previously described phase transitions in Ni-free Fe-rich orthopyroxenes, i.e., the initial α-opx (Pbca) transforms to β-opx (P21/c), then the latter transforms to γ-opx (Pbca). This indicates that the incorporation of a few mol% NiSiO3 does not influence the phase transition path of Fe-rich orthopyroxene. After the third phase transition, the structure (P21ca) of Ni-En31Fs65 resembles the previously reported β-popx observed in En90 at high pressure, although the onset pressure of the phase transition in Ni-En31Fs65 is ~7 GPa lower than that in En90. β-popx has a post-pyroxene structure that contains fivefold- and sixfold-coordinated Si cations. Our results indicate that the post-pyroxene structure is β-popx (P21ca) for either Fe-poor or Fe-rich orthopyroxenes, although the phase transition path before the pyroxene → post-pyroxene is compositionally dependent. Additionally, unlike the second and third transitions, whose onset pressures are monotonously decreased by increasing Fe content, the Fe effect on shifting the first transition is much more significant for orthopyroxenes within En <50 mol% than that within En >50 mol%.

Behavior of Carbothermal Dephosphorization of Phosphorus-Containing Converter Slag and Its Resource Utilization

Phosphorus-containing converter slag is a common waste in the iron and steel industry, and has the characteristics of high generation and low secondary-utilization values; however, the high-phosphorus content in converter slag limits its ability to be recycled during the steelmaking process. In this study, the dephosphorization behavior of converter slag by carbothermal reduction was studied through experiments and thermodynamic calculations. The results showed that the gas product of the converter slag produced by carbothermal reduction was mainly P2, and that part of P2 entered the iron phase to generate iron phosphate compounds. With the increase in Fe content, the amount of P2 also increased, which may provide a suitable new direction for the production of ferrophosphorus. Based on the carbothermal reduction theory, a new “circulating steelmaking process of converter steel slag gasification” was proposed and applied to Chengde Iron and Steel Group Co., Ltd. (Chengde, China). The industrial production practice showed that the process did not affect the dephosphorization effect of the next furnace, and that the average iron, steel, and slagging-material consumption per furnace was reduced by 4.74 kg and 608 kg, respectively. CO2 emissions were reduced by 4.86 kg, thus achieving the goals of energy saving, environmental protection, and efficient dephosphorization.

Effect of Sulfur Granular Municipal Solid Waste, Humic Acid, and Nano Fe-Oxide on Lead Uptake by Plants in a Calcareous Soil in the Presence of Thiobacillus

Soil poisoning with heavy metals is one of the most significant aspects of environmental research. In the soil treated with Thiobacillus, the effect of sulfur granular municipal solid waste (sulfur granular MSW), humic acid, and nano Fe-oxide on reducing Pb absorption by plants was investigated. Treatments consisted of applying sulfur granular MSW (0 and 30 t/ha), spraying humic acid (0 and 1.5 mmol/L), and using nano Fe-oxide (0 and 2% w/w) in the soil contaminated with Pb (0, 600, and 1200 mg/kg-soil). Plants were collected after 5 months, and the Pb content in the soil and plants was estimated by atomic absorption spectroscopy (AAS). The activity of ascorbate peroxidase (APX) and peroxidases (POX) enzymes were also determined. The use of 30 t/ha of sulfur granular MSW in the Pb-polluted soil reduced Pb concentration in the soil and plant by 13.4% and 15.1 %, respectively, while it increased Fe concentration by 15.2% in the plant. Using nano Fe-oxide (2% w/w) in the Pb-contaminated soil (600 and 1200 mg/kg soil) considerably enhanced Fe content in the plant. Pb absorption by plants was dramatically reduced by foliar application of humic acid. According to the findings of this study, the interaction effects of sulfur granular MSW, nano Fe-oxide, and humic acid significantly reduced the Pb absorption by plants. However, the impacts of soil physico-chemical characteristics and the kind of soil pollutant on plant Pb concentration cannot be ignored.

DEVELOPMENT, STANDARDIZATION, PHYSICO-CHEMICAL AND NUTRITIONAL ANALYSIS OF BISCUITS DEVELOPED WITH DIFFERENT REPLACEMENT LEVELS OF PUMPKIN FLESH POWDER

Present study was planned and conducted at Institute of Food Science and Nutrition, University of Sargodha and Food Technology Section, AARI Faisalabad during 2020, to develop and analyze pumpkin flesh powder (PFP) and to prepare, standardize and evaluate biscuits with 0, 5, 10 and 15% replacement levels of PFP. Full ripened pumpkins were sliced, dried and grinded to obtain PFP. Straight grade flour (SGF) and PFP were analyzed for physico-chemical properties. PFP exhibited greater (6.15 ± 0.08) a* (redness) and (36.94 ± 0.19) b* (yellowness) values, significantly higher contents of moisture (14.29 ± 0.05%), ash (1.36 ± 0.03%), fat (1.24 ± 0.03%) and fiber (1.82 ± 0.01%), as compared to SGF. Upon analysis of physical characteristics of developed biscuits, as replacement level of PFP was increased to 15%, with SGF to develop biscuits, a* and b* values of biscuits were significantly increased to 5.06 ± 0.079 and 28.01 ± 0.14 respectively, thickness was also significantly increased to 48.50 ± 0.75 mm, while width was significantly decreased. Chemical analysis of biscuits revealed a significant increase in ash, fat fiber, Na, K and Fe contents of biscuits with increasing level of replacement of PFP. Whereas, non-significant results for moisture and protein contents were found. The contents of Ca, Mg and P were significantly decreased in added PFP biscuits. Sensory evaluation of biscuits proved that 5 to 10% replacement level of PFP got good scores close to the control so up to 10% replacement level of PFP with SGF was acceptable to develop good quality, nutritional biscuits. By keeping in view, the nutritional profile of pumpkin an effort was made to highlight the nutritional significance of pumpkin, pumpkin powder and biscuits developed with addition of pumpkin powder.

Tunable Iron–Cobalt Thin Films Grown by Electrodeposition

Iron–cobalt (FeCo) alloys are highly desirable for their exceptional and adjustable physicochemical properties, particularly in the form of thin films. This study focuses on the growth of iron–cobalt (FeCo) alloy thin films using potentiostatic electrodeposition. The effects of applied voltage and FeCo stoichiometry on the morphology, structure, and magnetic properties of the films are investigated. The results indicate that the electrodeposition potential does not affect the overall stoichiometry or the structural and magnetic properties. However, it does impact film thickness and grain sizes. Higher applied potentials lead to thicker films with faster growth rates, as well as smoother and more homogeneous films with smaller grains. Films with different Fe:Co ratios (Fe90Co10, Fe50Co50, and Fe10Co90) are obtained, and their compositions have a direct impact on morphology, with the amount of Fe influencing film thickness, growth rates, and grain sizes. Increasing Fe content (50, 90%) leads to thicker films and smaller grains. Films with low Fe content (10%) exhibit a face-centered cubic (fcc) structural phase instead of the typical body-centered cubic (bcc) structure. All FeCo alloys display soft magnetic properties with characteristic coercivities, and the low Fe (10%) sample with the fcc structure exhibits the highest coercivity among all the samples. The nucleation and growth mechanisms are investigated using electrodeposition curves and the Scharifker and Hills model. Increasing the applied potential leads to thicker films and higher growth rates, with the nucleation mechanism identified as instantaneous nucleation in the diffusion-controlled regime.

Simulated nanoindentation into single-phase fcc Fe_{x}Ni_{1-x} alloys predicts maximum hardness for equiatomic stoichiometry

We investigate by molecular dynamics simulation the mechanical behavior of concentrated alloys under nanoindentation for the special example of single-phase fcc Fe_{x}Ni_{1-x} alloys. The indentation hardness is maximum for the equiatomic alloy, x=0.5. This finding is in agreement with experimental results on the strength of these alloys under uniaxial strain. We explain this finding with the increase of the unstable stacking fault energy in the alloys towards x=0.5. With increasing Fe content, loop emission from the plastic zone under the indenter becomes less pronounced and the plastic zone features a larger fraction of screw dislocation segments; simultaneously, the length of the dislocation network and the number of atoms in the stacking faults generated in the plastic zone increase. However, the volume of twinned regions in the plastic zone is highest for the elemental solids and decreases for the alloys. This feature is explained by the fact that twinning proceeds by the glide of dislocations on adjacent parallel lattice planes; this concerted motion is less efficient in the alloys. Finally, we find that surface imprints show increasing pile-up heights with increasing Fe content. The present results will be of interest for hardness engineering or generating hardness profiles in concentrated alloys.

Influence of iron seed priming on seed germination, growth and iron content in rice seedlings

The area under direct-seeded aerobic rice (DSR) is increasing in Indo-gangetic plains due to labor and water scarcity. However, iron (Fe) deficiency is a severe problem in DSR under coarse-textured soils, resulting in poor germination, interveinal chlorosis, and poor seedling establishment. Fe seed priming is a better option to ensure higher seed germination and optimum supply of Fe at initial growth stages. Hence, the experiment was conducted with seven seed priming treatments i.e. Control (hydropriming), 0.5% Fe through ferrous sulfate (FeSO4 7H2O), 1.0% Fe through FeSO4 7H2O, 0.25% Fe through ethylene diamine tetra acetic acid chelated iron (Fe-EDTA), 0.5% Fe through Fe-EDTA, 0.025% Fe through iron oxide nanoparticle (FeO NPs) and 0.05% Fe through FeO NPs. The Fe seed priming showed a significant increase in Fe content of paddy seeds over the hydropriming treatment. Among different treatments, FeSO4.7H2O (1.0% Fe) showed highest germination percentage (91.3%), root length (8.4%) and shoot length (9.4%) followed by FeSO4.7H2O (0.5% Fe) which was significantly higher over the control. But, the treatment involving Fe-EDTA (0.5% Fe) showed adverse effects on germination and seedling growth. Ferrous (Fe2+) iron and total Fe content in rice seedlings showed similar trends to total Fe content in primed seeds treated with different Fe sources. Thus, Fe seed priming of rice with FeSO4.7H2O (1.0%Fe) for 12 h was effective for higher germination percentage, greater iron content at initial growth stages and ameliorated the Fe deficiency in direct seeded aerobic rice.

Removal of BTEX from water system by synergistic flocculation of biosurfactant and iron salt

The adsorption micelle flocculation (AMF) effect of biosurfactants (rhamnolipids, RL) and polymerized ferric sulfate (PFS) on the removal of low molecular weight benzoic acid (benzoic acid and p-methyl benzoic acid) and phenol (2,4-dichlorophenol and bisphenol A) organics was investigated. The coexistence system of RL and organic matter was constructed, and the effects of pH, Fe concentration, RL concentration and initial concentration of organic matter on the removal effect were discussed. For benzoic acid and p-methyl benzoic acid, the increase of Fe and RL concentrations was beneficial to their removal rates under weak acidic conditions, and the removal rate of the coexistence system was higher for methyl benzoic acid (87.7 %) than for benzoic acid (78.6 %), which might be attributed to the stronger hydrophobicity of the coexistence system for methyl benzoic acid; while for 2,4-dichlorophenol and bisphenol A, pH and Fe concentration changes had less effect on the removal rate, but the increase in RL concentration was favorable to the removal rate, which was 93.1 % and 86.7 % for BPA and 2,4-dichlorophenol, respectively. These findings provide feasible ideas and directions for the removal of organics by AMF using biosurfactants.

Novel In Situ Fabrication of Fe-Doped Zinc Oxide/Tin Sulfide Heterostructures for Visible-Light-Driven Photocatalytic Degradation of Methylene Blue

Using a hydrothermal synthesis process, Fe-doped ZnO/SnS nanostructures were created and a variety of analytical methods were used to describe their characteristics. X-ray diffraction patterns were employed to confirm the hexagonal and orthorhombic crystal structures of ZnO and SnS, respectively. Nanorods and nanoparticle clouds were visible in TEM pictures, and XPS investigation verified that the dopant Fe ions were in the 3+ oxidation state. Additionally, absorption spectroscopy revealed a decrease in the energy bandgap with an increase in Fe content, and photoluminescence analysis demonstrated that the ZSF3 sample significantly reduced the rate of recombination of charge carriers. Impressively, the optimized sample (ZSF3) displayed 95.8% more photocatalytic activity during the 120 min degradation of MB dye. This study demonstrated that an easy hydrothermal procedure, carried out at 220°C for 12 hours, may be used to create iron-doped ZnO/SnS nanocomposites. The tunable energy bandgap characteristics of heterogeneous semiconducting materials and the effective charge carrier separation were thought to be the causes of the increased photocatalytic activity. Furthermore, the heterostructure of charge carriers was proposed to facilitate photocatalytic activity when exposed to light.

The removal of NO from flue gas by Fe/NaOH/H2O2 system

NO emitted from coal combustion was harmful to the environment. For most current wet denitrification technologies, obtaining the desired removal efficiency was always dependent on the contact time of NO with the reaction solution. In this paper, a novel Fe/NaOH/H2O2 technology was proposed to remove NO, which could obtain 90% NO removal efficiency when the flue gas residence time in solution was 3 s. The mechanism of H2O2 decomposition and NO removal were analyzed. Results demonstrated that Fe and NaOH together catalyzed H2O2 to produce radicals, and ⋅O2− radicals took the main responsibility in the process of NO removal. NO3− and NO2− were the final forms of NO. In addition, the effects of several common experimental parameters were investigated on the NO removal performance. The increase of H2O2 concentration, Fe concentration, solution pH and reaction temperature all had a positive effect on NO removal, but this process was also accompanied by an intensification of the useless decomposition of H2O2 (consumption of H2O2 in the form of O2). The addition of SO2 to the flue gas had a slight effect on the NO removal and the useless decomposition of H2O2.

Influence of 1:7 H phase stability on the evolution of cellular microstructure in Fe-rich Sm-Co-Fe-Cu-Zr magnets

Fe-rich Sm2Co17-type magnets have many essential applications prospects in high-temperature operation environments. However, the formation of complete cellular microstructure becomes increasingly difficult when the Fe content of Sm2Co17-type magnets exceeds 20 wt%. Herein, the phase stability of 1:7 H phase and its effect on the precipitation of the 1:5 H precipitates in Fe-rich Sm2Co17-type magnets are investigated. The results confirm that the stability of the 1:7 H phase decreases with the increasing of Fe content for the solution-treated magnets. Not only 2:17 R phase but also a lot of 2:17 R′ phase is found in solution-treated magnets when the Fe content exceeds 22 wt%. As the Fe content increases, the density of initial defects decreases for the growth of 2:17 R nanotwins in the solution-treated magnets. Furthermore, the segregation of Cu in the defects-aggregated cell boundaries weakened gradually. Consequently, the nucleation and precipitation of cell boundary precipitates is difficult, and the cellular microstructure becomes incomplete and coarse when the Fe content is above 22 wt%. The present work may provide a further insight for understanding the evolution of cellular microstructure depending on the phase decomposition behavior in Fe-rich Sm2Co17-type magnets.

Effect of Minor Fe, Si Contents on Microstructure and Property of 7085 Alloy during Fabrication Processes

Fe and Si elements can form non-dissolvable phases in Al-Zn-Mg-Cu alloys and furtherly affect the property of finished products while the influence of minor contents lacks sufficient investigations. In present work, 7085 alloy with different Fe and Si contents (named by LFS alloy, MFS alloy and HFS alloy as Fe and Si contents progressively enhanced) was investigated and corresponding microstructure and property during the whole fabrication were analyzed via OM, SEM and DSC observation and tensile property, fracture toughness and salty-spray corrosion property. The results showed that Fe-containing phase existed in as-cast microstructure of three alloys while part of Fe-containing phases of HFS alloy has Si element. After homogenization treatment, coarse eutectic phases had dissolved into the matrix while Fe-containing phase remained in the alloys. Similarly, Si element existed in some Fe-containing phases of HFS alloy. The order of area fraction of remaining Fe-containing phases for the three alloys was LFS alloy<MFS alloy<HFS alloy. After extrusion, Mg(Zn,Cu,Al)2 phase and Fe-containing phase possessed the majority, the former one was eliminated by solution treatment while the latter one had no obvious change. Under an unified aging treatment, the strength, elongation and fracture toughness were degraded with the increase of Fe and Si contents. Besides, the salt-spray corrosion property of HFS alloy was significantly inferior to LFS alloy and MFS alloy. This gave rise to a reference for controlling Fe and Si impurity of 7085 alloy for considering overall performance.

Role of Soil and Foliar-Applied Carbon Dots in Plant Iron Biofortification and Cadmium Mitigation by Triggering Opposite Iron Signaling in Roots.

In China, iron (Fe) availability is low in most soils but cadmium (Cd) generally exceeds regulatory soil pollution limits. Thus, biofortification of Fe along with mitigation of Cd in edible plant parts is important for human nutrition and health. Carbon dots (CDs) are considered as potential nanomaterials for agricultural applications. Here, Salvia miltiorrhiza-derived CDs are an efficient modulator of Fe, manganese (Mn), zinc (Zn), and Cd accumulation in plants. CDs irrigation (1mgmL-1 , performed every week starting at the jointing stage for 12 weeks) increased Fe content by 18% but mitigated Cd accumulation by 20% in wheat grains. This findingwasassociated with the Fe3+ -mobilizing properties of CDs from the soil and root cell wall, as well as endocytosis-dependent internalization in roots. The resulting excess Fe signaling mitigated Cd uptake via inhibiting TaNRAMP5 expression. Foliar spraying of CDs enhanced Fe (44%), Mn (30%), and Zn (19%) content with an unchanged Cd accumulation in wheat grains. This result is attributed to CDs-enhanced light signaling, which triggered shoot-to-root Fe deficiency response. This study not only reveals the molecular mechanism underlying CDs modulation of Fe signaling in plants but also provides useful strategies for concurrent Fe biofortification and Cd mitigation in plant-based foods.

Effect of Mn-based magnetic biochar /PS reaction system on oxidation of metronidazole

In order to fully exploit the potential of magnetic biochar-based persulfate (PS) systems, Mn was utilized to modify the magnetic biochar-based catalysts through impregnation-pyrolysis method. Taking metronidazole (MNZ), a typical antifungal drug, as the target contaminant, the reactivity of the synthesized magnetic biochar (MMBC) catalyst was evaluated. The degradation efficiency of MNZ in MMBC/persulfate system was 95.6%, which was 13.0 times higher than that in MBC/PS system. The characterization experiments confirmed the degradation of metronidazole by surface binding free radicals, the ·OH and 1O2 played the key role in remove of MNZ in the system of MMBC/PS. Physicochemical characterization, Fe(II) semi-quantitative analysis and masking experiments confirmed that the doping of MBC with Mn increased its Fe(II) content (43.0 mg/g), approximately 7.8 times higher than that of pristine MBC. The increase of Fe(II) content in MBC is the key reason to improve the optimization of MBC modified with Mn. Simultaneously, both Fe(II) and Mn(II) were the key components of PS activation by magnetic biochar. This paper presents a method to optimize the high efficiency of PS activation by magnetic biochar.