Increase In Zinc Content Research Articles

The Effects of Seed Inoculation with Bacterial Biofilm on the Growth and Elemental Composition of Tomato (Solanum lycopersicum L.) Cultivated on a Zinc-Contaminated Substrate

Biofilm obtained from Bacillus subtilis subsp. spizizenii inoculated on vegetable seeds has been shown to have plant growth-promoting capacity. Seed inoculation with biofilm produced by this strain could also reduce the adverse effects on plant growth caused by soil or substrate heavy metal overabundance. Therefore, the objective of this work was to evaluate the impact of biofilm inoculated on tomato (Solanum lycopersicum L.) seeds, which were planted on a substrate with artificially added zinc. First, seeds of the Río Grande tomato variety were exposed to increasing zinc concentrations, namely: 50, 100, 200, and 400 ppm, with and without bacterial biofilm inoculation. Zinc addition and seed inoculation affected germination parameters. For example, an extra 200 and 400 ppm of zinc led to high toxicity. Biofilm inoculation, however, reduced the noxious effects of excess zinc, bringing acute toxicity down to moderate. Then, tomato plants growing from inoculated and non-inoculated seeds were cropped for 4 months in both substrates with 400 ppm zinc and without added zinc. Extra zinc addition significantly (p < 0.05) reduced tomato root and shoot biomass, plant height, and fruit number at harvest time. However, seed biofilm inoculation avoided the harmful effect of zinc on plant growth parameters, fruit yield, and fruit quality. The roots and shoots of plants growing on contaminated substrates showed very noticeable increases in zinc levels compared to the control, while fruits only showed a much weaker zinc gain, even if this was significant (p < 0.05). Moreover, root shoot and fruit concentrations of elements other than zinc, (nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, iron, manganese, copper, lead, and cadmium) were not or only weakly affected by the addition of this metal to the substrate. In summary, the biofilm of B. subtilis proved to be effective as a bioinoculant to alleviate negative effects on tomatoes cropped in a substrate with excess zinc.

Enhancing optical properties of Ba-Ni ferrite through nonmagnetic ion doping for sustainable green technologies and renewable energy applications

Barium ferrite powder was produced using a standard ceramic procedure, and its structure and optical properties were investigated. X-ray diffraction analysis (XRD) showed that the powder had a w-type hexagonal structure. The crystallite size was at approximately 35–36 nm, with bulk density and lattice constants increasing as zinc concentration rose. Conversely, X-ray density and porosity decreased with the increasing zinc concentration. This material has useful optical properties, as well as the standard ferrimagnetic properties of barium ferrite, which make it suitable for use in recording media. Ferrimagnetic behavior, which is useful for recording media, occurs because the powder's crystallites have their unit cell axes aligned. Up to the near-infrared part of the spectrum, the powder was found to have a very low absorption coefficient. Both of these properties—an arrangement that gives rise to ferrimagnetism and a corresponding low optical density—make barium ferrite very attractive for high-density recording and microwave applications. Fourier transform infrared spectra of the samples were recorded in the wavenumber range of 400–4000 cm−1 and supported the X-ray diffraction findings by confirming the idea of the formation of W-type hexagonal ferrite by the presence of two prominent peaks at 454 and 591 cm−1 in the FTIR spectra. Zinc addition was also found to enhance the optical properties of the material. The UV–VIS analysis confirms that the band gap energy of Ba-Ni ferrite was indeed reduced by zinc doping. Values decrease from 3.34 eV to 3.20 eV for direct transitions and from 2.96 eV to 2.79 eV for indirect transitions, using Tauc equation. That means that zinc doping enhances the optical properties of Ba ferrite without affecting the hexagonal structure of Ba-Ni ferrite. Moreover, key parameters of optical performance such as the dielectric constant, the extinction coefficient, the penetration depth, and the refractive index show a dramatic increase with a rise in zinc concentration. These attributes make zinc-doped Ba-Ni ferrite a promising optoelectronic material. The material also showed high absorbance in the wavelengths ranging from 334 to 338 nm, which makes it good for the solar cell applications. Overall, zinc-doped Ba-Ni ferrite is a good candidate for sustainable and renewable energy applications. Our study of the optical properties of barium ferrite up to the near-infrared part of the spectrum demonstrated that the powdered material has a very low absorption coefficient. Indeed, the combination of ferrimagnetism and low optical density makes barium ferrite particularly appealing for use in high-density recording and microwave technology applications.

Alterations in tissue content of iron and zinc in mice bearing hepatoma 22a and their correction by zinc sulphate supplementation

It is known that many tumors induce iron and zinc deficiency in the organism. We studied the content of these metals, as well as the specific activity of two antioxidant metal-dependent enzymes – catalase and superoxide dismutase of three distal organs (thymus, liver and spleen) in animals bearing transplantable hepatoma 22a. These alterations were compared to weight changes of organs. On day 21 of tumor growth, as compared to control group, nonheme iron content in all three organs was decreased, and zinc content – only in the thymus. The specific activities of catalase and superoxide dismutase were both increased in the thymus, while in the liver activity of superoxide dismutase decreased. At the same time point thymic involution and splenomegaly were developed. In order to normalize metal content mice bearing hepatoma 22a were supplemented with 22 mkg of zinc sulphate per ml of drinking water during 3 weeks. Zinc sulphate supplementation partly compensated zinc deficiency in the thymus, increased zinc content in the liver and restored iron content in three organs. It also normalized superoxide dismutase activity in the liver and had no influence on enzymes in other organs. Zinc supplementation did not influence the weight of spleen and liver, but prevented the development of thymic involution. Moreover, metal deficiency in the thymus was restored while the activity of antioxidant enzymes remained unchanged. Based on this we can conclude that thymus involution in hepatoma 22a mice was associated with iron and zinc deficiency in this organ and was not linked with antioxidant enzyme activity, while splenomegaly had no relation to both types of parameters in the spleen. Thus, zinc sulphate positively influences metabolism of two vital trace elements – zinc and iron in animals bearing hepatoma 22a, what contributes to maintaining of the central immune organ – the thymus, and along with this it improves antioxidant system of the liver.

In Vitro Evaluation of Electrospun PCL Bioscaffold with Zinc-Doped Bioactive Glass Powder Addition.

Preparing electrospun fibers by applying a potential difference between a polymeric solution and a contacting substrate is increasingly attracting attention in tissue engineering applications. Among the numerous polymers, polycaprolactone (PCL) bioscaffold has been widely investigated due to its biocompatibility and biodegradability. Bioactive powder can be added to further improve its performance. In the present study, bioactive glass powder modified by adding 0-6 wt.% antibacterial zinc element (coded as ZBG) was prepared through the sol-gel process. Furthermore, PCL bioscaffolds with various ZBG additions were prepared using the electrospinning technique. The zinc-doped bioactive glass powder and electrospun PCL/ZBG bioscaffolds were evaluated using scanning electron microscopy, X-ray diffraction and Fourier-transform infrared spectroscopy to determine their structural properties. Additionally, in vitro bioactivity, biocompatibility and antibacterial performance were investigated. Experimental results showed that sol-gelled ZBG powder possessed superior bioactivity and 0.8 g ZBG was the optimal addition to prepare PCL/ZBG bioscaffolds with. All the electrospun PCL/ZBG bioscaffolds were biocompatible and their antibacterial performance against two S. aureus strains (SA133 and Newman) improved with increasing zinc concentration. Electrospun PCL/ZBG bioscaffolds exhibited excellent bioactivity and have great potential for biomedical application.

Hydroxyapatite layer evolution on silica-based (45S10P) bioactive glass-ceramic nanoparticles doped with Zn2+ ions: Augmentation of in vitro bioactivity, antibacterial activity and textural modification for bone regeneration

Zinc-incorporated bioactive glasses (BG) and bioactive glass-ceramic (BGC) nanoparticles (BGC-NPs) represent highly adaptable, biodegradable, and bioactive materials in tissue engineering and regenerative medicine. This study delves into the synthesis, characterization and biomedical implications of Zn2+ ions-doped 45S10P spherical BGC-NPs, employing analytical techniques and in vitro assays. The resulting (Zn2++ 45S10P) BGC-NPs, prepared using a modified Strober's method, exhibited spherical morphology with excellent dispersion, as verified by TEM, FE-SEM, and DLS analyses. XRD, FTIR, and FESEM analysis revealed an augmented hydroxyapatite (HAp) layer formation with increasing zinc content. Zeta potential analysis showcased a shift from negative to positive values after immersion in simulated body fluid (SBF), indicating the bioactive potential of the developed BGC-NPs. Hemocompatibility assays indicated the biocompatibility of all BGC-NPs, demonstrating minimal hemolytic effects with incorporating Zn2+ ions below a standard threshold (<5 % lysis). Further, the migration assay revealed the potentiality of the BGC-NPs to stimulate the migration of HeLa cells. Cell viability assays employing MG-63 osteoblast-like cells highlighted enhanced cell viability over time, underscoring their non-toxic nature and potential for tissue regeneration. Antibacterial assays displayed significant inhibitory effects against Gram-negative compared to Gram-positive bacteria, underscoring their potential for anti-infection applications. Overall, the results affirm the promising prospects of Zinc incorporation into 45S10P BGC-NPs for bone tissue regeneration applications.

Rietveld refined crystal structure, magnetic, dielectric, and electric properties of Zn substituted Ni-Mg ferrites

Sol − gel technique was used to synthesize Ni0.7-xZnxMg0.3Fe2O4 (Ni – Zn – Mg) ferrites with x = 0.1, 0.2, 0.3, 0.4, 0.5. Formation of single phase cubic spinel structure of the synthesized samples was confirmed by employing Rietveld refinement technique. Spherical and inhomogeneous distribution of grains was observed from Transmission Electron Microscopy (TEM) image. The frequency dependent initial permeability (μi), real part of initial permeability (μ′), imaginary part of initial permeability (μ″) was studied for synthesized samples. For zinc content x = 0.2 in Ni – Zn – Mg ferrites μi is observed to be high as compare to other compositions and that attributed to grain size. DC electrical resistivity (ρdc) analysis shows both conducting and semiconducting behavior for all the samples. Room temperature electrical resistivity values were observed to be lower for lower content of zinc and higher for higher content of zinc and that attributed to the hopping mechanisms at octahedral site. The decreasing trend of Curie temperature was observed with increase in zinc content in Ni – Zn – Mg ferrites. Frequency dispersive dielectric properties study of Ni – Zn – Mg ferrites revealed normal dielectric behavior.

Structural, dielectric, impedance, ferroelectric, piezoelectric, energy harvesting, and optical properties of Ca1-xZnx(Fe0.5V0.5)O3 ceramics

The present work mainly describes the fabrication and characterization (structural, micro-structural, dielectric, piezoelectric, optical, and energy-harvesting) of Ca1-xZnx(Fe0.5V0.5)O3 with x = 0, 0.05, 0.10, and 0.15 complex perovskite. All four compounds are prepared by using the solid-state reaction method (calcination temperature = 1100 °C (6 h) and sintering temperature = 1150 °C (7 h)). The room temperature XRD data analysis confirms all four compounds' single-phase orthorhombic structures. Different modes of vibrations are confirmed by Raman spectroscopy. The grain size increases from 1.09 μm to 2.53 μm with increased zinc concentration. The variation of dielectric constant with frequency has been explained based on Maxwell-Wagner polarization. The effects of grain and grain boundary have been confirmed by impedance spectroscopy, which contributes to the conduction and relaxation mechanism of the compounds. The d33, g33, and energy harvesting performance gradually increase with an increase in zinc concentration, confirming the enhancement of the compounds' piezoelectric properties. The decrease in the band gap from 3.58 eV (x = 0) to 3.00 eV (x = 0.15) confirms the enhancement of optical properties.

350 Awardee Talk: Beef cattle mineral nutrition: What do we know and where do we go from here

Abstract Trace minerals are pivotal in enhancing cattle growth and ensuring profitability in beef production. Historically, supplementation strategies have aimed at preventing deficiencies, significantly improving growth and reproductive performance. However, as cattle breeding has evolved to achieve remarkable growth rates, the challenges related to health and stress during the feeding period have intensified. This presentation explores refined trace mineral recommendations, focusing on zinc’s “stress requirement” for cattle undergoing transit and health challenges, and its impact on performance. The segmented nature of the beef industry, necessitating multiple transports, induces physiological stress and oxidative stress, highlighting the need for tailored mineral supplementation. Further, when recognizing feedlot cattle as the high-performing athletes they are, the potential benefits of adjusted trace mineral concentrations become apparent. Preliminary findings suggest that optimal zinc concentrations may exceed current National Academies of Sciences, Engineering, and Medicine (NASEM) 2016 recommendations, whereas for other minerals like copper and manganese, the existing guidelines remain appropriate. This presentation will explore the differential effects of increasing dietary zinc and copper in conjunction with various growth-promoting technologies. Preliminary data indicates that increasing zinc concentrations can linearly enhance average daily gain (ADG) and hot carcass weight (HCW), especially when using potent anabolic implants, while the response to increased copper concentrations exhibits a more quadratic relationship with performance. Building upon the foundational work of pioneering researchers in the field of mineral nutrition, this presentation advocates for the continuous refinement and optimization of trace mineral supplementation strategies. By integrating cutting-edge technologies and fostering collaborative research efforts, we aim to further enhance the sustainability of the beef industry. A deeper understanding of trace mineral requirements in the face of modern production challenges will pave the way for more precise and effective nutritional strategies.

Effectiveness of Zinc Supplementation for Sepsis Treatment: A Single-Center Retrospective Observational Study.

Zinc plays an important role in sepsis; however, the effectiveness of zinc supplementation and the appropriate dose remain unclear. This study aimed to verify the effectiveness of zinc supplementation and the appropriate dose in patients with sepsis. This single-center retrospective observational study included 247 patients with sepsis from 1 April 2015 to 31 March 2023 who were receiving ventilatory management. The patients were divided into three groups according to the zinc supplementation dose: <15 mg, 15-50 mg, and ≥50 mg. The <15 mg, 15-50 mg, and ≥50 mg groups had 28 (19%), six (21%), and 16 deaths (22%) at discharge, with no statistically significant difference (p = 0.36). No statistically significant differences were observed in the length of intensive care unit (ICU) stay (p = 0.06). A higher supplementation dose corresponded with a statistically significant increase in blood zinc concentration in the first week (38.5 ± 16.6 µg/dL, 58.8 ± 19.7 µg/dL, 74.2 ± 22.5 µg/dL, respectively; p < 0.01) but not in the second or third weeks (p = 0.08, 0.19, respectively). Zinc supplementation did not reduce the mortality rate or length of ICU stay or contribute to an increased serum zinc concentration. High-dose zinc supplementation may not be effective during acute sepsis.

Metagenomic insights into the prokaryotic communities of heavy metal-contaminated hypersaline soils

Saline soils and their microbial communities have recently been studied in response to ongoing desertification of agricultural soils caused by anthropogenic impacts and climate change. Here we describe the prokaryotic microbiota of hypersaline soils in the Odiel Saltmarshes Natural Area of Southwest Spain. This region has been strongly affected by mining and industrial activity and feature high levels of certain heavy metals. We sequenced 18 shotgun metagenomes through Illumina NovaSeq from samples obtained from three different areas in 2020 and 2021. Taxogenomic analyses demonstrate that these soils harbored equal proportions of archaea and bacteria, with Methanobacteriota, Pseudomonadota, Bacteroidota, Gemmatimonadota, and Balneolota as most abundant phyla. Functions related to the transport of heavy metal outside the cytoplasm are among the most relevant features of the community (i.e., ZntA and CopA enzymes). They seem to be indispensable to avoid the increase of zinc and copper concentration inside the cell. Besides, the archaeal phylum Methanobacteriota is the main arsenic detoxifier within the microbiota although arsenic related genes are widely distributed in the community. Regarding the osmoregulation strategies, “salt-out” mechanism was identified in part of the bacterial population, whereas “salt-in” mechanism was present in both domains, Bacteria and Archaea. De novo biosynthesis of two of the most universal compatible solutes was detected, with predominance of glycine betaine biosynthesis (betAB genes) over ectoine (ectABC genes). Furthermore, doeABCD gene cluster related to the use of ectoine as carbon and energy source was solely identified in Pseudomonadota and Methanobacteriota.

Micronutrients and Allergic Diseases: A Mendelian Randomization Study

Introduction: Previous studies have indicated a controversy regarding the association between dietary micronutrient concentrations and the risk of allergic diseases. In this study, we employed Mendelian randomization (MR) analysis using data from two samples to investigate the causal relationship between circulating micronutrient concentrations and three allergic diseases. Methods: In this study, we considered 16 circulating micronutrients as exposure variables (beta carotene, calcium, copper, folate, iron, lycopene, magnesium, phosphorus, selenium, vitamin A1, vitamin B6, vitamin B12, vitamin C, vitamin D, vitamin E, and zinc); and three common allergic diseases (allergic asthma [AA], atopic dermatitis [AD], and allergic rhinitis [AR]) as outcomes. The inverse variance weighted (IVW) method was primarily applied for MR analysis, supplemented by MR-Egger and weighted-median methods to corroborate the IVW results; and sensitivity analysis was conducted to ensure the robustness of the MR assumptions. Results: Our results revealed that an increase in serum phosphorus and zinc concentrations may diminish the risk of AA, while for AD an increase in serum zinc concentration may reduce the risk, but an increase in serum vitamin C concentration may elevate the risk. As for AR, an increase in serum phosphorus and selenium concentrations appeared to be associated with a reduced risk. We did not find evidence for an association between other micronutrients and the risk of allergic diseases. Conclusion: Our study indicates that an increase in serum phosphorus and zinc concentrations may reduce the risk of AA, while an increase in serum zinc concentration may reduce the risk of AD, but an increase in serum vitamin C concentration may elevate the risk of AD. An increase in serum phosphorus and selenium concentrations is associated with a reduced risk of AR. This provides additional support for research on the effects of micronutrients on allergic diseases.

An Ex-Ante Analysis of the Impact of Biofortified Zinc Rice on Dietary Zinc Inadequacy: Evidence from Bangladesh, Indonesia, and the Philippines

BackgroundSouth, East, and Southeast Asia are among the regions of the world with the highest estimated prevalence of inadequate zinc intake. Because populations in those regions eat rice as their main staple, zinc biofortification of rice can potentially improve zinc intake, especially among the most vulnerable. ObjectivesWe modeled the impact of the consumption of zinc-biofortified rice on zinc intake and inadequacy among women of childbearing age and young children nationally in Indonesia, the Philippines, and at a subnational level in Bangladesh. MethodsWe conducted an ex-ante analysis by applying increments of zinc content in rice, from a baseline level of 16 parts per million (ppm) to 100 ppm, and based on rice consumption data to substitute levels of conventional rice with zinc-biofortified rice varying between 10% and 70%. ResultsAmong all datasets evaluated from these 3 countries, the prevalence of dietary zinc inadequacy at baseline was 94%–99% among women of childbearing age, 77%–100% among children 4–5 y old, and 27%–78% among children 1–3 y old. At the current breeding target of 28 ppm, zinc-biofortified rice has the potential to decrease zinc inadequacy by ≤50% among women and children in rural Bangladesh and among children in the Philippines where consumption of rice is higher compared with Indonesia. ConclusionsOur analysis shows that increasing zinc content in rice ≤45 ppm reduces the burden of zinc inadequacy substantially, after which we encourage programs to increase coverage to reach the highest number of beneficiaries.

Bioaugmentation of Phanerochaete concrescens KS7 for enhanced growth and zinc nutrition in rice (Oryza sativa L.)

Bioaugmentation of microbial strains could act as sustainable intervention in soil for enhancing the availability of nutrients. Zinc deficiency is widely reported across the world and application of zinc based fertilizers mostly resulted in formation of unavailable zinc in soil. A fungus with zinc solubilisation was isolated from rice and identified as Phanerochaete concrescens KS7. Inoculation of fungus in culture medium resulted in decrease of pH to 4.4 and analysis of medium revealed higher content of citric and gluconic acid in comparison with uninoculated broth. Indole acetic acid production by the strain was found to be enhanced in presence of tryptophan under broth conditions. Zinc solubilisation potential of strain was quantified in medium amended with insoluble zinc source. There was enhanced root growth and significantly higher zinc concentration in rice seedling on inoculation with KS7. There was increase in plant height, leaf area, number of grains per panicle and grain yield per plant on inoculation with P. concrescens in two selected varieties of rice grown in zinc deficient soil. Partition analysis was done for zinc in root, stem and grains and there was significant increase of zinc content in rice grain on inoculation with KS7. Total and available zinc was quantified from soil after harvest of rice and found that zinc contents were higher in soil of KS7 inoculated plants. Phanerochaete concrescens KS7 could act as potential solubilizer of zinc in soil and improve the zinc content of crop produce especially in zinc deficient soils.

Biological Removal of Zinc (II) by Fusarium solani under Different Modes of Operational Strategies: A Comparative Study

The goal of the current batch biosorption experiment was to determine how well Fusarium solani (isolated from soil) resting cells could remove zinc (II) from aqueous solution. With an increase in pH (up to pH 5.0) and an increase in initial zinc (II) concentration of up to 500 mg/L, the specific zinc (II) removal increases. By increasing biomass content from 2.5 to 5.5 g/L, the specific zinc (II) removal remained nearly constant. The investigations also utilised resting cells from various growth stages and at an initial zinc (II) concentration of 500 mg/L, the maximum specific zinc (II) uptake (51.7 mg/g) was accomplished (36 h old). The comparison of the results revealed that cells in a growing state (63.9 mg/g) can achieve the highest selective uptake. Hence, the uptake of zinc(II) under various operational strategies was only done with growing cells. The biological uptake of zinc (II) was then done in a fed batch mode of operation using Fusarium solani growing cells. Increased volume pulse feeding (IVPF) and constant volume pulse feeding (CVPF) were used to study the fed batch process and the impacts of these operational methods on biological performance were contrasted with those of a traditional batch process. According to batch experiments, at pH 5.0 and an initial zinc (II) ion concentration of 500 mg/l, the maximum specific zinc (II) removal was 63.9 mg/g. The maximal specific zinc (II) removal in the IVPF process was determined to be 45.47 mg/g and 33.58 mg/g, but the values in the CVPF process were 33.12 mg/g and 22.59 mg/g respectively for the first and second pulse feedings in both cases. The zinc (II) uptake found in prior investigations carried out by the current authors employing the continuous mode of operation was then compared with these results. The process could be run for a longer period of time with a maximum specific zinc (II) removal of 52.8 mg/g when operating in a continuous mode which was shown to be the optimal operational strategy.

Effect of Zinc Ion in Water on Properties of Ordinary Portland cement Concrete

The study is aimed at investigating the effect of presence of Zinc in water on setting times and compressive strength of cement concrete. In the present study, the effect of Zinc (Zn) on setting time and compressive strength of cement is assessed under laboratory conditions. The research program included tests of setting times and Mechanical strengths up to 28 days. In this research, the cement concrete cubes were cast with deionized water and deionized water containing the Zinc ions at various concentrations. The concentrations of Zinc (Zn) tested for different samples are 10, 50, 100, 500, 1000, 2000, 3000, 4000 and 5000 mg/L. The experimental results show that the presence of Zinc in deionized water accelerates both initial and final setting times up to 2000 mg/L. Zinc in deionized water up to 2000 mg/L there is a nominal change in compressive strength at early age (3-day). Beyond 2000 mg/L there is a significant change in the compressive strength at early ages as well as 28-day. Comparisons of the Zinc with those of control mix levels reveal that the presence of Zinc increases the compressive strength. The rate of increase in compressive strength is with increase in concentration of Zinc.

The structural, magnetic and electrical properties of zinc-doped orthorhombic calcium ferrite nanoparticles: Memory device and high-frequency applications

Calcium ferrite nanoparticles (NPs), doped with Zinc in the range of 10–50[Formula: see text]mol%, were synthesized through a solution combustion method using citrus Limon extract as a reducing agent, followed by calcination at 500∘C. The synthesized samples are characterized with different techniques. Bragg reflections confirmed the formation of orthorhombic crystal structure. The shifting of the peak toward higher angle side is observed with increase in the dopant concentration. The surface exhibited irregular shapes and sized NPs with pores and voids in their morphology. The direct energy band gap increases from 2.91 to 2.97[Formula: see text]eV with increase in Zinc concentration. Further, magnetic and dielectric properties were carried out to know their importance in the high-frequency devices. Magnetic parameters, such as saturation magnetization (Ms), remanence (Mr), and coercivity (Hc) values, are discussed. Ms, Mr and Hc increase with increase in dopant concentration upto 30[Formula: see text]mol% and thereafter decreases. The dielectric studies revealed a decreasing dielectric constant from 2.98 to 1.84 as the dopant concentration increased. These findings suggest the potential use of these samples in memory devices and high-frequency applications.

Synthesis, XPS and NEXAFS spectroscopy study of Zn, Cr codoped bismuth tantalate pyrochlores

The study investigated the formation of inhomophase ceramics through Zn doping in Bi2СrTa2O9.5–Δ. It was found that all Bi2ZnxCr1–xTa2O9.5–Δ (0.3 ≤ x ≤ 0.7) investigated samples crystallized in the pyrochlore structural type (sp. Gr. Fd-3m) and contained an admixture of triclinic β-BiTaO4 (up to 24 wt %, sp. gr. P-1), with the admixture concentration proportional to the degree of zinc doping. It was shown that impurities in the samples could be eliminated by creating a defective bismuth sublattice proportional to the impurity content, resulting in single-phase Bi2–yZnxCr1–xTa2O9.5–Δ (y ≤ 0.5, 0.3 ≤ x ≤ 0.7) samples with the pyrochlore structure. The unit cell parameter of pyrochlore increased with an increase in zinc ion content in the samples from 10.4493 Å (x = 0.3) to 10.4976 Å (x = 0.7). The microstructure of ceramics was represented by individual slightly melted grains 0.5–2 μm in size, which increased in size and fuse with each other with an increase in zinc content. The near edge X-ray absorption fine structure (NEXAFS) and X-ray photoelectron spectroscopy (XPS) data showed that zinc doping did not change the oxidation degree of bismuth and tantalum in pyrochlore, with the ions in charge states Bi(+3), Zn(+2) and Ta(+5). The study also observed an energy shift of the absorption band in the Ta 4f spectrum toward lower energies (ΔE = 0.55 eV) characteristic of tantalum ions with an effective charge (+5–δ) and a shift of the Bi 4f7/2 and Bi 4f5/2 bands shift to lower energies with increase in x(Zn), due to the distribution of some Zn(II) ions in the bismuth position. The oxidation degree of chromium ions in the samples was mainly (+3), with some chromium ions oxidized and having an oxidation degree close to (+6) according to NEXAFS data. The studied ceramics showed promise as dielectrics for multilayer ceramic capacitors and devices for microwave applications due to their low sintering temperature and high porosity.

К вопросу об использовании мелиоративных приемов в целях формирования биогеохимических барьеров

The amount of lands subject to contamination with heavy metal ions is increasing due to mining of minerals. Therefore, research on the use of various composite sorbents / ameliorants, which in combination with perennial plants can act as a biogeochemical barrier to the spread of heavy metal ions in the environment, is currently relevant. In the “soil–and-plant” system, use of the peat-and-diatomite ameliorant granulated on site in the direction of the man-made flow showed a high degree of survival of the awnless brome grass (Brōmus inērmis) compared with zero survival on the reference area. The dynamics of heavy metal accumulation in the plant biomass shows an increase in the content of copper and zinc, in comparison with the background values during the second year of research, while during the third year there is a decrease in the content of copper in the biomass from 235 to 40 mg / kg, with an increase in zinc content from 473 mg / kg to 510 mg / kg. The data obtained confirm the limits of metal fluctuations in the plant biomass established by previous researchers. At the peat-and-diatomite ameliorant sites, an increase in the concentration of Cu2+ and Zn2+ was also observed in comparison with the other survey locations, which indicates the possibility of using granular peat-and-diatomite ameliorant as a material to create a network of biogeochemical barriers perpendicular to the direction of the man-made flow.

Impact of ZnO nanopriming on physiological and biochemical traits of wheat (Triticum aestivum L.) seedling

To ascertain the ideal dosage of ZnO NPs (Zinc Oxide Nanoparticles), we conducted an investigation on the priming effects of varying concentrations of ZnO NPs on germination and physio-biochemical parameters of wheat. In this study, ZnO NPs were synthesized and characterized for their physico-chemical properties followed by confirmation of the formation of ZnO NPs. Throughout this study, wheat seeds were subjected to ZnO NPs at various concentrations of 5, 50, 100, 250, and 500 ppm for a period of 4 h via continuous aeration. The primed seeds were sowed in plastic bags, allowed to grow for 21 days, following which comprehensive evaluations of physio-biochemical attributes were conducted. At 250 ppm, an impressive 100% of seeds successfully germinated compared to the control group. The examined physiological factors such as shoot length, root length, and fresh as well as dry weights of leaf and root tissues all exhibited notable increases with the ascending concentrations of ZnO NP up to 250 ppm. However, beyond this threshold, at 500 ppm, these parameters experienced a decline. Inductively coupled plasma atomic absorption spectrophotometer (ICP-AAS) measurements validated the progressive increase in Zinc content in the nanoprimed seedlings, further affirming the dose-dependent trend. Zinc oxide nanoparticles notably improved key biochemical features, including elevated levels of total chlorophyll, malondialdehyde (MDA), total protein, and the accumulation of osmolytes such as proline and glycine-betaine. Additionally, the presence of ZnO NPs led to increased activity of antioxidant enzymes like superoxide dismutase (SOD) and catalase in a dose-dependent mananer. Collectively, the amassed data underscores the efficacy of the 250 ppm ZnO NPs treatment, which emerged as superior in comparison to both the control group and other administered treatments. These findings underscore the potential of ZnO NPs at a concentration of 250 ppm as a valuable seed nanopriming agent, effectively enhanced germination and robust early-stage growth in young plants.

Effect of methyl jasmonate seed treatment on physiological processes in wheat plants under conditions of increased zinc content in substrate

The effect of methyl jasmonate (MeJA, 10 μM) seed treatment on seed germination, growth and some parameters of photosynthesis and water metabolism in wheat (Triticum aestivum L.) plants of the Zlata variety grown at optimal (5 mg/kg) or excessive (46 mg/kg) zinc content in the substrate was studied. It was shown that elevated zinc concentrations inhibited shoot growth and led to a decrease both in chlorophyll content and transpiration intensity. MeJA seed treatment stimulated germination, but slightly inhibited plant growth during the tillering phase at optimum zinc content in the substrate. Conversely, at higher zinc levels, MeJA seed treatment reduces its inhibitory effect on plant growth and transpiration rate.