Amount Of Mn Research Articles

La0.8Sr0.2Mn0.8Co0.2O3-δ perovskite as an efficient functional electrocatalyst for oxygen reduction reactions

The negative effects of the widespread and rough use of fossil energy have promoted the emergence of new energy technologies. Cost-effective electrocatalysts play an irreplaceable role in energy conversion and storage, especially oxygen reduction reactions (ORR) catalysts. While the reserves of precious metal catalysts are rare and expensive, it is of prime importance to develop catalysts that can replace precious metals. In the present work, La0.8Sr0.2Mn0.8Co0.2O3-δ (LSMC) with Mn and Co is successfully prepared by sol-gel method and subsequent calcination. The characterizations of physical phase, microstructure, BET and valence state of elements demonstrate that LSMC material possesses ample mesoporous structure, large specific surface area, and multivalent elements, which can provide abundant active sites for ORR. The electrochemical tests reveal that the LSMC delivers outstandingly higher electrocatalytic activity for ORR, relatively lower overpotential and Tafel slope and a better long-term stability than the other perovskites (LSM, LSC) under alkaline condition. Furthermore, the coupling effects of high content of high-valence Co, multivalent Mn and large amounts of adsorbed oxygen endow the catalyst excellent ORR electrocatalytic activity. The present work investigating the effect of Mn and Co elements on the electrocatalysis of LSMC perovskite, will provide the possibility of developing a new type of perovskite electrocatalyst with excellent ORR electrocatalytic activity and low cost.

Pivotal role of MnOx physicochemical structure in soot oxidation activity

Arising an interest in climate and health problems, catalytic soot oxidation and its mechanism need to be understood, in order to effectively reduce PM (particulate matter) emissions from industry and transportation. Here, a synergistic effect of the Mn physicochemical structure on the soot oxidation activity of Ti-based oxide catalysts is investigated. To unravel the structural change and role of different Mn species, a comparison of different Mn loading and pretreatment conditions was done. While a fine loading with different Mn arrangements is observed by XRD analysis, a comparative XPS study of these Mn catalysts reveals the predominant presence of Mn3+ oxidation state and optimal combination of surface adsorbed and lattice oxygen species (ratio of 1.07) imparts a promotional role in soot oxidation activity. Furthermore, the TPR, O2-TPD, and TEM analysis represent that the increased Mn amount with different configurations led to a decreased reducibility, difficulty in lattice oxygen accessibility, and changed the morphology of MnOx species from cubic to hexapod and/or truncated octahedra associated with the presence of α-Mn2O3-C, β-MnO2 and/or α-Mn2O3-TO, respectively. The presence of smaller segregated cubic particles, ease of reducibility, and predominant presence of Mn3+ species led to superior performance even at lower 10 %Mn supported TiO2 catalyst and was revealed with an activation energy of 112.9 kJ mol−1. This proves the consequence of a proper design of an optimum Mn structure on oxide supports for an efficient soot oxidation reaction.

Revealing opposite behaviors of catalyst for VOCs Oxidation: Modulating electronic structure of Pt nanoparticles by Mn doping

Revealing the role of Pt electronic structure in the catalytic degradation of VOCs is of great significance for developing efficient catalysts. Herein, the catalytic oxidation of acetone and benzene on the ZSM-5 confined Pt-based catalyst (Pt@Z) was investigated. Surprisingly, after introducing Mn to Pt@Z, the activity of the PtMn@Z catalyst for acetone was significantly increased, while the activity for benzene was decreased. It was found that Mn introduction led to electron transfer to Pt, which enhanced the adsorption of acetone and gaseous oxygen, and promoted acetone degradation. However, the high electron density of Pt inhibited the adsorption and degradation of benzene. Importantly, we used this phenomenon to regulate the electronic structure of Pt by simply adjusting the amount of Mn and achieving the synergistic removal of benzene and acetone. Therefore, this work provided an idea for the design of highly efficient catalytic materials with mixed VOCs.

An UV/Vis/NIR optical absorption spectroscopic and color investigation of transition-metal-doped gahnite (ZnAl2O4 spinel) crystals grown by the flux method

Abstract Synthetic flux-grown end-member gahnite, ZnAl2O4, and several different colored crystals doped with one or more transition metals including Mn, Ni, Cr, Co, and Fe were studied by electron microprobe methods and UV/Vis/NIR single-crystal optical absorption spectroscopy. The first major objective was to measure and assign the various electronic absorption features. The second was to analyze quantitatively the crystal colors using the experimental spectra and the CIE 1931 color-space-chromaticity diagram. The microprobe results show that the doped gahnites have transition metal concentrations between about 0.001 and 0.1 cations per formula unit. The spectrum of colorless, nominally pure ZnAl2O4 displays no absorption in the visible region. Microprobe analysis of a light-blue gahnite crystal reveals small amounts of Ni and Mn. The UV/Vis/NIR spectrum does not indicate any dd-electronic transitions relating to Mn. All absorption features also cannot be fully interpreted using Tanabe-Sugano diagrams for Ni2+ in either octahedral or tetrahedral coordination. A series of seven slightly different colored gahnites with differing concentrations of Cr3+ and most also containing smaller amounts of Ni was investigated. The spectrum of a one pink crystal shows two intense absorption features in the visible region. They are assigned to spin-allowed 4A2g → 4T2g (4F) and 4A2g → 4T1g (4F) transitions of VICr3+. Other spectra display additional weak bands and lines that are most probably spin-forbidden dd-transitions of Ni2+. These gahnites with Ni and Cr show varying purple colorations depending on the concentrations of both metals. Two more deeply blue gahnites contain Co2+ as demonstrated by their UV/Vis spectra but not by microprobe analysis. Two intense absorption features at ~7440 and ~16 850 cm–1 are observed and assigned to the spin-allowed transitions 4A2 → 4T1 (4F) and 4A2 → 4T1 (4P) of Co2+, respectively. Complex absorption fine structure, caused by spin-orbit and/or vibronic interactions, is also observed. Three different gahnites with yellow to orange colorations contain measurable Mn. Their spectra are similar in appearance and display several weak IVMn2+ spin-forbidden transitions located above 20 000 cm–1. The spectra of two green gahnites show several Fe spin-forbidden electronic transitions arising from single, isolated IVFe2+ and VIFe3+ cations between 10 000 and 25 000 cm–1. The intensities of some of the VIFe3+-related bands can be increased through exchange-coupled interactions with next nearest IVFe2+ neighbors. The colors of various doped gahnites and the end-member galaxite are analyzed using their single-crystal absorption spectra in the visible region. Their dominant wavelength, λk, and hue saturation, pc, values are given on the CIE 1931 color-space-chromaticity diagram and are discussed. The Hex colors of all crystals are calculated and can be compared to those of the studied crystals.

Combined modeling and experimental characterization of Mn segregation and spinodal decomposition along dislocation lines in Fe–Mn alloys

In the current work, Mn enrichment at dislocations in Fe–Mn alloys due to segregation and spinodal decomposition along the dislocation line is studied via modeling and experimental characterization. To model these phenomena, both finite-deformation microscopic phase-field chemomechanics (MPFCM) and Monte Carlo molecular dynamics (MCMD) are employed. MPFCM calibration is carried out with the same Fe–Mn MEAM-based potential used in MCMD, as well as CALPHAD data. Simulation results for Mn segregation to, and spinodal decomposition along, straight screw and edge dislocations as well as dislocation loops, are compared with characterization results from atom probe tomography (APT) for two Fe–Mn alloy compositions. In contrast to classical Volterra (linear elastic) dislocation theory, both MPFCM and MCMD predict a non-zero hydrostatic stress field in screw cores. Being of much smaller magnitude than the hydrostatic stress in straight edge cores, much less solute segregates to screw than to edge cores. In addition, the segregated amount in screw cores is below the critical concentration of 0.157 for the onset of spinodal decomposition along the line. On the other hand, results from MPFCM-based modeling imply that the concentration dependence of the solute misfit distortion and resulting dependence of the elastic energy density on concentration have the strongest effect. The maximum amount of Mn segregating to straight edge dislocations predicted by MPFCM agrees well with APT results. On the other hand, the current MPFCM model for Fe–Mn predicts little or no variation in Mn concentration along a straight dislocation line, in contrast to the APT results. As shown by the example of a dislocation loop in the current work, a change in the hydrostatic stress along the line due to changing character of dislocation does lead to a corresponding variation in Mn concentration. Such a variation in Mn concentration can also then be expected along a dislocation line with kinks or jogs.

Environmental forensics evaluation of residual soybean sludge using trees of Brazilian savannah

Truck and train are the primary transport means for soybean shipments to national or international markets from Brazil. Substantial amounts of grain residues are dispersed throughout the transport and may accumulate in various places by the runoff. The objective of this study was to evaluate the contamination and mortality of Brazilian savannah trees due to the accumulation of soybean runoff that comes from a grain storage yard. Xylem samples were collected from 28 dead trees in a forest where residues severely polluted the natural environment. Increment cores at breast height were also taken from 25 living trees for control procedure. All samples were analyzed by X-ray densitometry and microfluorescence (XRF) techniques. No differences were observed in the xylem densitometry profile from bark to pith between dead and living trees, indicating that the stagnation in cell production and tree growth occurred drastically after the accumulation of soybean residual sludge, which was confirmed by temporal analysis of satellite images. Significantly higher S, P, Ca and Fe concentrations were observed close to the bark in dead trees. The roots of dead trees accumulated higher amounts of Al, Si, S, Ca and Mn. Higher K, Ca and Si concentrations and lower Mn concentrations were observed in trees closer to the polluted area, and it indicates the need for soil remediation. However, As, Pb and Cd, markers of fertilizers and pesticides in soybean production, were not detected by the analyses performed. It is likely that the residual soybean sludge and its fermentation process during the rainy season (tree - growing season) have generated toxic concentrations of inorganic constituents, that together with warmer soil conditions caused the death of many trees. This study provides tools for the assessment of the environmental impact of soybean production through a novel protocol for monitoring the physical and chemical patterns of tree growth using rapid microscopic scale X-ray techniques.

Groundwater Quality Assessment in Korba Coalfield Region, India: An Integrated Approach of GIS and Heavy Metal Pollution Index (HPI) Model

The goal of this study was to examine the water quality for drinking and domestic purposes in the Korba coalfield region of Chhattisgarh, India. The Korba Coalfield region has seen the collection of fifteen groundwater samples from different places. The content of eight metals was determined using ICP-MS instruments: aluminum (Al), barium (Ba), cadmium (Cd), iron (Fe), magnesium (Mn), lead (Pb), nickel (Ni), and zinc (Zn). Spatial distribution maps were produced using GIS software to make it simple to understand the groundwater’s quality. The groundwater samples were collected during the pre-monsoon season and the amount of Al, Ba, Cd, Fe, Mn, Pb, Ni, and Zn exceeded the ideal drinking water standards in a few sites. The elevated metal concentrations in the study region’s groundwater could be hazardous to the quality of water. The HPI value based on mean concentration was calculated to be 21.64, which is significantly lower than the reference pollutant index score of 100. The HPI calculation revealed that 73.33% of groundwater samples had low HPI values, 6.67% had medium HPI values, and the remaining 20% had high HPI values. The correlation between heavy metals and HPI was calculated; HPI is positively correlated with Fe (r > 0.9471), Pb (r > 0.9666), and Zn (r > 0.9634), indicating that these elements contribute significantly more to heavy metal concentration in the various samples examined than the other selected elements. The box plot seems to be a graphical representation of the outcomes of the different parameter concentrations which show the mean, maximum, and minimum metal values. The cluster analysis was performed and it was classified into two clusters. Cluster-1 comprises 14 members (93.33%) of the water samples examined and is distinguished by relatively low Ba (<700 μg.L-1), pH, TDS, Al, Fe, Cd, Mn, Pb, and Zn concentrations. Cluster-II is made up of 1 member (6.67%), which is primarily made up of groundwater samples (GW-10) taken in the KCF region, India. High values of HPI are found in the eastern portion of Chhattisgarh’s KCF region, reflecting the spatial distribution of metals. Heavy metal leaching from open-pit mining and transit routes was observed to have contaminated groundwater in the eastern section of the research region.

Metal impregnation on steel converter slag as an oxygen carrier

AbstractOxygen carriers used in chemical looping processes operated with biofuel are affected by the inorganic matter of the fuel. It is therefore expected that the lifetime of the oxygen carrier is limited, and preferably low‐cost oxygen carriers should be used. Oxygen carriers based on iron ore or steel manufacturing waste products are available in significant quantities at low cost. However, it is common for these types of materials that their reactivity is low. This study investigates the effect of adding small amounts of more reactive elements into steel converter slag, also called LD slag.Slag particles were wet impregnated with 2 or 5 wt.% of Ni, Cu, Mn, or Ce. The new material's morphology was evaluated using X‐Ray Diffraction and SEM‐EDS. Changes in reactivity towards CO, CH4 and the model tar molecule benzene were evaluated using a bench‐scale laboratory fluidized bed reactor.It was observed that even small amounts of either Ni, Cu, or Mn could increase reactivity toward CO. Both Cu and Mn formed phases with LD slag that released oxygen via CLOU (chemical looping with oxygen uncoupling) and increased the conversion of methane and benzene. Ni and Ce doping also increased methane conversion but had only a minor effect on the benzene conversion. © 2023 The Authors. Greenhouse Gases: Science and Technology published by Society of Chemical Industry and John Wiley & Sons Ltd.

Effects of heat treatment routes on microstructure and damping properties of Mg–Zn–Y–Mn alloys

The effects of different heat treatment processes on the morphology and damping properties of long-period stacking order (LPSO) phase in Mg-4.9Zn-8.9Y-xMn alloys were studied. The microstructure analysis shows that the as-cast second phase presents a vein-shaped distribution at the grain boundary, and the heat treatment temperature has a significant effect on the morphology of the second phase. After heat treatment at 540 °C, the LPSO phase at the grain boundary changes into rod-like; When the heat treatment temperature is 550 °C, the LPSO phase changes into bulk or flocculent, and part of the LPSO phase melts into the matrix.In this process, the addition of Mn also has an important influence on the morphology transformation of LPSO phase. An appropriate amount of Mn can divide the bulk LPSO into several small parts during heat treatment, thus forming a large number of dispersed LPSO phases. In general, heat treatment and Mn elements can affect the mechanical and damping properties of the alloy. Heat treatment can reduce the mechanical properties of the alloy, but effectively improve the damping properti es of the alloy. With the addition of Mn into the alloy, the mechanical properties of the alloy can be improved without significantly reducing the damping.

More negative charges on roots enhanced manganese(II) uptake in leguminous and non-leguminous poaceae crops.

Manganese (Mn) is an essential micronutrient for plants, whereas excess Mn(II) in soils leads to its toxicity to crops. Mn(II) is adsorbed onto plant roots from soil solution and then absorbed by plants. Root charge characteristics should affect Mn(II) toxicity to crops and Mn(II) uptake by the roots of the crops. However, the differences in the effects of root surface charge on the uptake of Mn(II) among various crop species are not well understood. The roots of nine legumes and six non-legume poaceaewere obtained by hydroponics and the streaming potential method and spectroscopic analysis were used to measure the zeta potentials and functional groups on the roots, respectively. The results indicate that the exchangeable Mn(II) adsorbed by plant roots was significantly positively correlated with the Mn(II) accumulated in plant shoots. Legume roots carried more negative charges and functional groups than non-legume poaceae roots, which was responsible for the larger amounts of exchangeable Mn(II) on legume roots in 2h and the Mn(II) accumulated in their shoots in 48 h. Coexisting cations, such as Ca2+ and Mg2+ , were most effective in decreasing Mn(II) taken up by roots and accumulated in shoots than K+ and Na+ . This was because Ca2+ and Mg2+ could compete with Mn(II) for active sites on plant roots more strongly compared to K+ and Na+ . The root surface charge and functional groups are two important factors influencing Mn(II) uptake by roots and accumulation in plant shoots. © 2023 Society of Chemical Industry.

Nitrogen-containing carbon nanofibers as supports for bimetallic Pt-Mn catalysts in aqueous phase reforming of ethylene glycol

Aqueous phase reforming (APR) of ethylene glycol was performed at 225 °C and 30 bar in batch and continuous reaction conditions. The effect on the APR performance by functionalizing carbon supports with nitrogen and adding Mn to Pt-based catalysts was investigated. The presence of nitrogen species on the carbon surface and Mn-addition (PtMn) improved the catalytic activity and promoted H2 production. XPS results suggest that the enhancement of the catalytic activity may be attributed to charge transfer from platinum to the nitrogen groups and Mn. Pt-based catalysts were stable under the studied reaction conditions, while up to 97 % of the manganese leached into the liquid solution during APR. However, the catalytic activity was maintained even with such significant decrease in Mn content, indicating that only a small amount of Mn is necessary to maintain the promotional effect on Pt during APR.

The Impact of Zinc on Manganese Bioavailability and Cytotoxicity in HepG2 Cells.

Despite their essentiality, several studies have shown that either manganese (Mn) or zinc (Zn) overexposure may lead to detrimental health effects. Although Mn is transported by some of the SLC family transporters that translocate Zn, the role of Zn in hepatocellular Mn transport and Mn-induced toxicity have yet to be fully characterized. The human hepatoma cell line, HepG2, is utilized. Total cellular Mn and Zn amounts are determined after cells are treated with Zn 2 or 24h prior to Mn incubation for additional 24h with inductively coupled plasma-based spectrometry and labile Zn is assessed with the fluorescent probe FluoZin-3. Furthermore, mRNA expression of genes involved in metal homeostasis, and mechanistic endpoints associated with Mn-induced cytotoxicity are addressed. These results suggest that Zn protects against Mn-induced cytotoxicity and impacts Mn bioavailability to a great extent when cells are preincubated with higher Zn concentrations for longer duration as characterized by decreased activation of caspase-3 as well as lactate dehydrogenase (LDH) release. Zn protects against Mn-induced cytotoxicity in HepG2 cells possibly due to decreased Mn bioavailability. Additionally, mRNA expression of metal homeostasis-related genes indicates possible underlying pathways that should to be addressed in future studies.

Synthesis of Ag and Mn/ZnO nanoparticles using a hydrothermal method - A brief study and their role in the electrocatalytic oxidation of glucose in alkaline media

Ag and Mn/ZnO were synthesized via a low-temperature hydrothermal process and applied as glucose oxidation reaction (GOR) catalysts. The sample characterization was performed by scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX), which revealed homogenous clustered nanoparticles for synthesized materials. The various amounts of Ag and Mn were loaded in ZnO nanostructure and their electrocatalytic effect on GOR was investigated by electrochemical techniques such as cyclic voltammetry (CV) and electrochemical impedance spectroscopy in an alkaline solution containing 3 mM glucose and 0.1 M NaOH. The Ag/ZnO and Mn/ZnO with 50% and 60% loading, respectively, were identified as the best electrocatalysts. The experimental data showed that the larger effective surface area of Ag/ZnO-50 (6.9 cm2) and Mn/ZnO-60 (9.25 cm2) accompanied by faster glucose diffusion coefficient due to the effective impact of Ag and Mn loading on the ZnO nanostructure improved the GOR for Ag/ZnO-50 and Mn/ZnO-60 compared to the ZnO.

Influence of Mn Content in the Alloy on the Oxidation, Electrical and Volatilization Behavior of Co-Coated Steel Interconnects

Two Co-alloy-coated steels with 1.0 wt% and 3.0 wt% Mn content were subjected to 1000 h of thermal exposure (750 °C) in air. The coated alloys displayed an increased oxidation rate as the Mn content varied between 1.0 wt% and 3.0 wt%. And Co coating was thermally converted into a three-layer structure composed of Cr-rich oxide (inner layer), mixed oxide with Co, Fe, Mn and Cr (middle layer) and doped Co3O4 spinel oxide (outer layer). Regardless of the Mn content, only a small amount of Mn was incorporated in the Co3O4 spinel. The area specific resistance for the Co-coated Fe-Cr containing 1.0 wt% Mn was as low as 5.37 mΩ cm2 subsequent to oxidation (lasting for 1000 h). Compared to the cathode with the uncoated alloy present, the polarization resistance of the cathode in the presence of the Co-coated alloy increased very slowly under the conditions of open circuit potential set as 750 °C and 200 h, and Cr deposition on the cathode surface declined noticeably. This showed that the Co coating effectively inhibited outward diffusion of Cr to poison the cathode during long-term exposure.

Nutritional and Phytochemical Investigation of Boerhaavia diffusa L. an Edible Wild Vegetable in South West Nigeria

The leaves and roots of Boerhaavia diffusa L. were analysed for phytochemical, proximate and mineral compositions. The results of the qualitative phytochemical screening revealed the presence of alkaloids, saponins, phlobatanins, cardiac glycosides and reducing sugar in both the leaves and roots of the plant. More so, Tannins and phenols were found in the roots while flavonoids and terpenoids were found in the leaves. The results of the quantitative composition of the phytochemicals showed that the roots and leaves of the vegetable were rich sources of alkaloids (19.91±0.74% and 28.57±0.30%), saponins (66.65±0.83% and 45.91±0.67%) and cardiac glycosides (45.13± 0.13% and 56.29± 0.25%). Proximate results showed that the roots and leaves of the wild vegetable had low moisture content (14.14±0.23% and 14.34±0.02%), ash content (5.32± 0.04% and 4.09 ±0.42%), crude protein (4.80± 0.05% and 2.42 ± 0.06 %), very low crude fat (0.40±0.10% and 0.45 ± 0.59%), high crude fiber (29.65 ±0.00% and 30.44± 0.42%) and moderate Carbohydrate (45.65± 0.09% and 48.29 ± 0.09%) respectively. The vegetable was rich in Na, K, Ca, Mg and Fe with moderate amount of Cu, Zn, and Mn while Pb and Ni (heavy metals) were not detected. This wild vegetable investigated contained bioactive phytochemicals that might support its excellent therapeutic uses in the treatment and prevention of diseases. The vegetable could also serve as energy and mineral rich food supplement.

Measurement System for Short-Pulsed Magnetic Fields.

A measurement system based on the colossal magnetoresistance CMR-B-scalar sensor was developed for the measurement of short-duration high-amplitude magnetic fields. The system consists of a magnetic field sensor made from thin nanostructured manganite film with minimized memory effect, and a magnetic field recording module. The memory effect of the La1-xSrx(Mn1-yCoy)zO3 manganite films doped with different amounts of Co and Mn was investigated by measuring the magnetoresistance (MR) and resistance relaxation in pulsed magnetic fields up to 20 T in the temperature range of 80-365 K. It was found that for low-temperature applications, films doped with Co (LSMCO) are preferable due to the minimized magnetic memory effect at these temperatures, compared with LSMO films without Co. For applications at temperatures higher than room temperature, nanostructured manganite LSMO films with increased Mn content above the stoichiometric level have to be used. These films do not exhibit magnetic memory effects and have higher MR values. To avoid parasitic signal due to electromotive forces appearing in the transmission line of the sensor during measurement of short-pulsed magnetic fields, a bipolar-pulsed voltage supply for the sensor was used. For signal recording, a measurement module consisting of a pulsed voltage generator with a frequency up to 12.5 MHz, a 16-bit ADC with a sampling rate of 25 MHz, and a microprocessor was proposed. The circuit of the measurement module was shielded against low- and high-frequency electromagnetic noise, and the recorded signal was transmitted to a personal computer using a fiber optic link. The system was tested using magnetic field generators, generating magnetic fields with pulse durations ranging from 3 to 20 μs. The developed magnetic field measurement system can be used for the measurement of high-pulsed magnetic fields with pulse durations in the order of microseconds in different fields of science and industry.

New ternary powder metallurgy Ti alloys via eutectoid and isomorphous beta stabilisers additions

A group of new ternary Ti alloys bearing eutectoid and isomorphous beta stabilising elements was created to be manufactured through the conventional powder metallurgy route. The effect of the simultaneous addition of the same amount of Mn and Nb on the manufacturability, properties, and hardening behaviour was investigated. The ternary alloys are composed of the α-Ti and β-Ti phases and have a lamellar microstructure resulting from the slow cooling upon sintering. However, the size of the equiaxed α grains and of the α + β lamellae is monotonically reduced, especially the interlamellar spacing, as the amount of alloying elements increases. Due to their physical properties, Mn enhances and Nb hinders densification during sintering resulting in a decreasing trend of the relative density with the alloying elements content. Consequently, the resistance to plastic deformation increases (UTS, 514–726 MPa), the ductility decreases (elongation, 13.2–2.6%), and the fracture mode changes from intergranular to transgranular. The new ternary alloys share the same hardening mechanism, but the amount of deformation after necking is, generally, higher for lower amounts of Mn and Nb.

Effect of Malva neglecta and lactulose on survival of Lactobacillus fermentum and textural properties of synbiotic stirred yogurt.

Yogurt is a popular dairy product and its consumption has been progressively growing over the past few decades by raising consumers' health-consciousness. As yogurt is growing in popularity, manufacturers are continuously seeking for bioactive components such as probiotics and prebiotics, to produce functional yogurt with more beneficial health effects. Therefore, this study aimed to evaluate the effect of Malva neglecta (MN, 0, 5, 10 and 15%) and lactulose (0, 1 and 2%) as prebiotic substances on survival of Lactobacillus fermentum in a half-fat synbiotic stirred yogurt. The results revealed that with increasing MN and lactulose concentrations, the count of Lb. fermentum significantly increased (p < 0.05). At the end of 21-day cold storage, the count of probiotics in yogurt sample having 2% lactulose and 10-15% MN significantly was higher than control (8.37-8.4 vs. 7.73 Log cfu/g). With increasing the amount of MN and lactulose, firmness and chewiness of yogurt samples decreased while adhesiveness increased (p < 0.05). Scanning electron microscopy assessment shown that addition of MN and lactulose resulted in a higher moisture retention in the void spaces. The results revealed that by incorporating lactulose and MN in yogurt formulation, an appropriate synbiotic yogurt could be produced as a novel functional product.

Iron and Manganese Oxidation States, Bonding Environments, and Mobility in the Mining-Impacted Sediments of Coeur d’Alene Lake, Idaho: Core Experiments

The mobility of a metal in mining-impacted sediments is determined by the environmental conditions that influence the metal’s oxidation state and bonding environment. Coeur d’Alene Lake, USA, has been impacted by legacy mining practices that allowed the hydrologic transport of mining waste to the lakebed, resulting in substantial amounts of redox-sensitive Fe and Mn along with Ag, As, Cd, Cu, Hg, Pb, Sb, and Zn. Future lake conditions may include algal blooms and additional algal detritus at the sediment–water interface, which may alter Fe and Mn forms that can influence their, and other metal(loid)s, mobility during seasonal anoxia. Cores of the lakebed sediments were exposed to anoxic and anoxic + algal detritus conditions for 8 weeks. Sediment samples were collected biweekly for analysis of Fe and Mn oxidation states and bonding environments by synchrotron-based X-ray absorption spectroscopy. Over the 8-week period and at a location 12.5 cm deep in the sediments, anoxic and anoxic + algae conditions produced limited changes in Fe and Mn oxidation states and bonding environments. At a location 2.5 cm below the sediment–water interface, the anoxic condition promoted a relatively stable environment in which Fe and Mn oxidation states and bonding environments did not vary greatly during the experiment. At the 2.5 cm depth, the anoxic + algae condition substantially altered the Mn oxidation state distribution and bonding environment, but this condition did not strongly influence the Fe oxidation state distribution or bonding environment. The anoxic + algae condition increased the presence of Mn3+, produced Mn4+ at select times, altered the Mn bonding environment, and temporarily increased the release of Mn into porewater. The algae influence on sediment and porewater Mn likely occurred because of the increased formation of organo-Mn complexes produced during algae-enhanced enzymatic processes. The lack of influence of algal detritus on sediment and porewater Fe and the formation of soluble organo-Mn complexes may limit the potential increase in the mobility of other metal(loid)s with future lake conditions.

Risk assessment of trace metals in Solanum lycopersicum L. (tomato) grown under wastewater irrigation conditions

Heavy metal contamination of food crop plants is viewed as a global issue. Heavy metals like cadmium (Cd), copper (Cu), lead (Pb), chromium (Cr), zinc (Zn), nickel (Ni), arsenic (As), cobalt (Co), and mercury (Hg) are poisonous. Depending on their concentration and capacity for bioaccumulation, they can provide a range of health risks.This research sought to investigate the effects of toxic metals (TMs) on the growth characteristics of produced tomatoes grown under wastewater irrigation. Additionally, it looked into the potential repercussions of both domestic and foreign individuals consuming this plant. In south Cairo, Egypt, two study locations were looked into: a control site in Abu Ragwan, which received water from tributaries of the Nile River, and a contaminated site in El-Shobak El-Sharky, which had raw industrial wastewater. The nutrients of soil and tomato plants (N, P, and K) decreased (P < 0.01), while TMs increased (P < 0.001) significantly as a result of using wastewater for irrigation. Except for Cu, all examined TM accumulating in tomato plants’ roots as opposed to shoots had a bioaccumulation factor (BF) > 1. However, the tomato plant’s shoot had solely undergone Pb and Ni translocation and storage, with a translocation factor (TF) > 1. A significant amount of Fe (5000.1 mg kg−1), Pb (360.7 mg kg−1), and Mn (356.3 mg kg−1) were present in the edible fruits. The ingestion of contaminated crops increases the daily intake rate of metals (DIR). The values of the high hazard quotient (HQ) were obtained (2073.8 and 2558.9 for Pb, 574.0 and 708.3 for Cd, and 41.1 and 50.7 for Fe for adults and children, respectively). Therefore, tomato plants grown in soils irrigated with untreated wastewater may offer a greater danger to human health, indicating that they should not be grown as a crop for human consumption.