Calcium Metal Research Articles

Production and properties of powder and pigments from bacuri (Platonia insignis Mart) rinds

Bacuri (Platonia insignis Mart) pulp content does not reach 20 % of the fruit's weight, rind corresponds to 64–70 % of the raw material, and presents phenolic compounds which suggests the possibility of obtaining colored compounds by complexation with metals. This work studied the bacuri rind powder without treatment, as we as with different metals (calcium, iron, zinc, selenium, copper, magnesium and aluminum) to evaluating which ones had potential for application after the complexation process. The best results in complexation, FT-IR spectroscopy, and color change were obtained with iron and aluminum salts. Temperature and pH had a strong influence on the color of the pigments. At room temperature, complexed with iron and aluminum salts in the range of pH 5 and 6 showed a significant color difference (p < 0.05) from the control (without treatment). The results of colors in the terracotta range (yellow to reddish brown) can be especially recommended for future studies for cosmetics, as well as plant-based doughs, or other chemical applications, with prospects for replacing yellow tartrazine and caramel, in specific application, according its properties.

Determination of trace analytes in nuclear grade Calcium Metal Samples by Axially Viewed Inductively Coupled Plasma – Atomic Emission Spectrometric technique

An Inductively Coupled Plasma – Atomic Emission Spectrometric (ICP-AES) method has been developed for the direct determination of 19 analytes namely, Al, B, Be, Cd, Co, Cr, Cu, Fe, Li, Mg, Mo, Mn, Ni, Pb, Pd, Si, Ta, V and W at trace concentration levels in calcium matrix. In nuclear industry, quality control and assurance of nuclear fuels and associated materials for trace metallic impurity contents form an integral part of the system for the smooth functioning of the reactor for the stipulated time span. In this context, it was required to determine trace analytes in nuclear grade Calcium which is used as a reducing agent for the production of U, Th, Pu, etc. in nuclear industry. Using axial ICP-AES, initially calibration curve for Ca with 396.847nm analytical line was obtained. Systematic studies were carried out to identify various analytical wavelengths of the analyte elements which are almost free from Ca, being the main matrix and calibration curves were obtained. For all analytes and Ca, detection limits and sensitivity values were calculated. To validate the method, three synthetic samples with analyte contents in the range of 0.1 - 5 g/mL and Ca at 1 mg/mL were analyzed, the % recovery being in the range of 80-120% with precision better than 5% RSD. The method was found to be useful for the direct determination of the elements of interest in calcium matrix and was applied for the analysis of two nuclear grade real life calcium metal samples.

Influence of alkali metal formates and calcium formate on workability, hydration and basic properties of reactive powder concrete

AbstractThis work aims to study whether it would be possible to use alkali metal formates and calcium formate in order to increase the workability of reactive powder concrete (RPC) and how these additives affect hydration, mechanical properties and mineralogical composition of RPC. These substances were added together with superplasticizer. Therefore, paper deals with possibility of increase in workability which would be higher when compared to the sole addition of only the superplasticizer themself. The effect of alkali metal formates and their replacement with calcium formate on slump flow, mechanical properties and pH of RPC was studied. Furthermore, the influence of potassium formate and its replacement with calcium formate and with calcium oxide on the hydration of RPC was observed with the help of isothermal calorimetry and thermal analysis. The results showed that the addition of studied compounds allows to achieve an increase in RPC slump flow. However, it is necessary to add these substances in an optimal ratio of alkali metal formate/calcium formate because a higher content of calcium formate leads to a decrease in slump flow. For ideal ratios, the compressive strength after 90 days is still above 218 MPa and the flexural strength is still above 23 MPa. In calorimetric measurements, it was observed that the addition of potassium formate leads to a decrease in the total amount of heat developed in the induction period. According to thermal analysis, additions of the studied additives to RPC caused changes in the content of portlandite and calcite.

The Impact of Biotechnologically Produced Lactobionic Acid on Laying Hens' Productivity and Egg Quality during Early Laying Period.

Lactobionic acid (Lba), an oligosaccharide aldonic acid, has demonstrated various health-promoting benefits and applications in diverse areas. Lba has been recognized for its multifunctional properties, such as metal ion chelation and calcium sequestration. This study aimed to evaluate the effects of supplementing the diet of early-laying hens with Lba (EXP group) on their performance and the physical-chemical properties, and nutritional quality of eggs. The 12-week study involved 700 Sonja breed hens per group, with the EXP group's diet enriched with 2% of biotechnologically produced Lba, while the control group (CON) received no Lba supplementation. Lba supplementation influenced both the hen's performance and egg quality, particularly in terms of egg production and fatty acid accumulation. Performance in the EXP group was significantly improved (p < 0.05), showing a 4.6-8.9% increase compared to the CON group at all experiment stages. Lba also promoted an increase in monounsaturated fatty acid (MUFA) content, particularly palmitoleic and vaccenic acids. Overall, Lba supplementation enhanced both the productivity of laying hens and the nutritional value of eggs during the early laying period.

Refining of Secondary Pb with Retention of Sn Using Al and Ca Additions

AbstractLead grid from spent lead-acid batteries contains significant amounts of tin and antimony. In classical pyro-refining processes of lead, tin oxidizes and is transferred to dross, making its recovery problematic and expensive. This paper presents an innovative method of pyro-refining lead using metallic aluminum and calcium to purify the lead from contaminants while retaining a higher amount of tin than in the traditional process. The changes in the chemical composition of an impure lead alloy containing tin, under the influence of refining by adding Al and/or Ca, are discussed based on laboratory-scale studies. Microanalysis of the metallic dross formed during the process was conducted. Analyses of the metallic dross microstructures showed that lead impurities, such as Sb, As, Cu, Se, and Te, tend to accumulate in areas containing Al or Ca. The amount and form of dross produced in industrial practice indicate that its removal would be challenging. Therefore, in the second part of the study, the metallic dross was subjected to a reduction process, and the resulting products were analyzed for their chemical and phase composition. The analyses indicate that the degree of impurities return to the lead during reduction varied significantly depending on the method used.

Navigating the combinations of platelet-rich fibrin with biomaterials used in maxillofacial surgery.

Platelet-rich fibrin (PRF) is a protein matrix with growth factors and immune cells extracted from venous blood via centrifugation. Previous studies proved it a beneficial biomaterial for bone and soft tissue regeneration in dental surgeries. Researchers have combined PRF with a wide range of biomaterials for composite preparation as it is biocompatible and easily acquirable. The results of the studies are difficult to compare due to varied research methods and the fact that researchers focus more on the PRF preparation protocol and less on the interaction of PRF with the chosen material. Here, the literature from 2013 to 2024 is reviewed to help surgeons and researchers navigate the field of commonly used biomaterials in maxillofacial surgeries (calcium phosphate bone grafts, polymers, metal nanoparticles, and novel composites) and their combinations with PRF. The aim is to help the readers select a composite that suits their planned research or medical case. Overall, PRF combined with bone graft materials shows potential for enhancing bone regeneration both in vivo and in vitro. Still, results vary across studies, necessitating standardized protocols and extensive clinical trials. Overviewed methods showed that the biological and mechanical properties of the PRF and material composites can be altered depending on the PRF preparation and incorporation process.

Analysis of Differential Gene Expression under Acute Lead or Mercury Exposure in Larval Zebrafish Using RNA-Seq.

This study was first conducted to investigate the effects of acute lead exposure on developing zebrafish embryos or larvae from 24 to 120 h post-fertilization (hpf). Our data showed that treatment with 50-200 μM lead significantly affected larval survivability and morphology compared to the respective control. Second, we chose 120 hpf larvae treated with 12.5 μM lead for RNA sequencing due to its exposure level being sufficient to produce toxic effects with minimum death and lead bioaccumulation in developing zebrafish. A total of 137.45 million raw reads were obtained, and more than 86% of clean data were mapped to the zebrafish reference genome. Differential expression profiles generated 116 up- and 34 down-regulated genes upon lead exposure. The most enriched GO terms for representative DEGs were ion transport and lipid metabolism. Third, a comparison with the dataset of mercury-regulated gene expression identified 94 genes (64 up-regulated and 30 down-regulated) for exposure specific to lead, as well as 422 genes (338 up-regulated and 84 down-regulated) for exposure specific to mercury. In addition, 56 genes were co-regulated by micromolar mercury and lead treatment, and the expression of thirteen genes, including mt2, ctssb.1, prdx1, txn, sqrdl, tmprss13a, socs3a, trpv6, abcb6a, gsr, hbz, fads2, and zgc:92590 were validated by qRT-PCR. These genes were mainly associated with metal ion binding, proteolysis, antioxidant activity, signal transduction, calcium ion or oxygen transport, the fatty acid biosynthetic process, and protein metabolism. Taken together, these findings help better understand the genome-wide responses of developing zebrafish to lead or mercury and provide potential biomarkers for acute exposure to toxic metals.

Influence of Sodium Lauryl Sulfate Anionic Micelles on the Complex Equilibria of Divalent Metal Ions with Isoleucine Amino Acid

The main objective of the present investigation is the formation analysis of metal-ligand complexes of isoleucine with divalent calcium, magnesium and zinc metal ions in various concentrations of sodium dodecyl sulphate (0.0, 0.5, 1.0, 1.5, 2.0 and 2.5 percent w/v). To look into the impact of the concentration of negatively charged micelles, the parameters were changed and the possible chemical species of isoleucine that interact with the metal ions, are being studied. The experiment was performed using pH meter at 303 K using NaCl to keep ionic strength stable at 0.16 mol dm-3 in the presence of anionic surfactant sodium dodecyl sulphate (SDS). The determination of the correction factor was conducted via the computer program SCPHD. The computational software MINIQUAD75 is utilized to determine the stability constants of ligand-metal complexes through the analysis of titration data. Based on statistical features such as skewness, 2, kurtosis and crystallographic R-factor, the best fit to the complicated speciation was selected. The metal ions Ca (II), Mg (II) and Zn (II) formed complexes ML, ML2 and ML2H2 for Ca (II), Mg(II) and ML, ML2 and ML2H for Zn (II) through the complexation of isoleucine. In order to validate the accuracy of the final established model, deliberate defects were introduced into the relevant components.

Detection and assessment of heavy metals concentration in wheat leaves collected from the vicinity of Sahiwal coal power plant, Pakistan, employing a modern data analysis approach

ABSTRACT Heavy metal pollution in food crops has become a global issue, especially in staple crops like wheat and rice. Electricity production utilising coal, ignites this issue in crops grown in the surrounding areas of coal power plants. Keeping this view in mind, the concentration of six heavy metals (HMs) Calcium (Ca), Cadmium (Cd), Chromium (Cr), Cobalt (Co), Lead (Pb) and Magnesium (Mg) in wheat leaves have been assessed in this study. Fifty samples of wheat leaves have been collected from the surrounding areas of the coal power plant in Sahiwal. The samples were prepared using the wet digestion method (WDM). Finally, these samples have been sent for analysis via atomic absorption spectroscopy (AAS). The limit of detection (LOD) and limit of Quantification (LOQ) of AAS were calculated with the help of blank samples. The concentration of Ca, Cd, Cr, Co, Pb and Mg in wheat leaves were 1.0187 ± 0.549 mg/kg, 0.00484 ± 0.00403 mg/kg 00,416 ± 0.00334 mg/kg, 0.0534 ± 0.0351 mg/kg, 0.035 ± 0.018 mg/kg, 0.464 ± 0.200 mg/kg respectively. The concentration of all understudy metals was below the Food and Agriculture Organization/World Health Organization (WHO/FAO) standards except for Co, in one sample. However, the concentration of heavy metals may increase, which may have profound repercussions. Therefore, preventive measures should be taken in this regard. The neutrosophic approach has been utilised to examine the variation of the heavy metals content in wheat leaves. This study provides a solid scientific foundation for future appropriate actions and management of heavy metals contamination in food crops near coal-fired power stations.

Enhanced transport anisotropy of Bi film through carrier mobility modulation controlled by calcium metal

Ca-doped Bi films were fabricated on the glass substrate using the molecular beam epitaxy (MBE). The systematic evolution for the preferred orientation, transport properties and surface morphology of Bi films were observed in the change of doping content. The measurement results show the adjustability of the preferred orientated surface morphology and Bi film carrier mobility. As the doping content increases, the mobility ratio four-fold and increases the anisotropy. Transport measurement simplifies the characteristic analysis of topological quantum materials. This work controls the material quantum property by doping Ca using MBE, which extends the potential application of quantum anomalous Hall effect-based devices.

Influence of Sodium Dodecyl Sulfate Anionic Micelles on The Complex Equilibria of Divalent Metal Ions with L-Leucine Amino Acid

The main objectives of the present investigation are the formation analysis of metal-ligand complexes of L-Leucine with divalent calcium, magnesium, and zinc metal ions in various concentrations of sodium dodecyl sulphate (0.0, 0.5, 1.0, 1.5, 2.0, and 2.5 percent w/v). To also look into the impact of the concentration of negatively charged micelles, the parameters that were changed, and the possible chemical species of L-Leucine that interact with the metal ions that were being studied. The experiment was performed using pH meter at 303 K using NaCl to keep your ionic strength stable of 0.16mol dm-3 in the presence of anionic surfactant, sodium dodecyl sulphate (SDS). The determination of the correction factor was conducted via the computer program SCPHD. The computational software MINIQUAD75 is utilized to determine the stability constants of ligand-metal complexes through the analysis of titration data. Based on statistical features such as skewness, 2, kurtosis, and crystallographic R-factor, the best fit to the complicated speciation was selected. The metal ions Ca (II), Mg (II), and Zn (II) formed complexes ML, ML2, and ML2H2 for Ca (II), and ML, ML2, and ML2H for Mg (II) and Zn (II) through the complexation of L-Leucine. In order to validate the accuracy of the final established model, deliberate defects were introduced into the relevant components.

Determination of Some Minerals and Heavy metals in Raw Cow’s Milk

Milk is a healthy and nutritious food. Its ability to be consumed by all age groups and its easy accessibility increase the importance of milk in our diet. As technological developments increase, so does environmental pollution. As a result of this pollution, metals and metal mixtures reach animals and humans through the food chain. This situation negatively affects the health of living organisms. In addition, excessive intake of some mineral substances can also be toxic. The contamination of heavy metals in food occurs through various pathways. The risk of metals in the composition of the containers used in the production of acidic foods such as milk and cheese dissolving and passing into the product is more likely to occur than in other foods. For this purpose, in our research, 10 samples of raw cattle milk collected from different regions of Muş province were analyzed for the amounts of calcium, magnesium, sodium, potassium, zinc, iron, copper, manganese, and heavy metals lead and cadmium using Atomic Absorption Spectrometry device. The samples' lead, cadmium, iron, copper, and manganese contents were determined as 0.40±0.01-0.19±0.01, 0.38±0.00-0.20±0.00, 1.96±0.01-0.24±0.01, 0.50±0.00-0.11±0.00 and 0.20±0.00-0.12±0.00 mg/L, respectively. The highest levels of calcium (433.45±0.00 mg/L) and potassium (1146.25±0.02 mg/L) were detected in sample S10. The lowest levels of magnesium (197.81±0.00 mg/L) and sodium (661.17±0.01 mg/L) were found in sample S3. The zinc contents of the samples varied between 8.25±0.00-14.51±0.00 mg/L. The results obtained were evaluated considering the factors affecting the amount of mineral substances and heavy metal contamination in the milk.

Electrode materials for calcium batteries: Future directions and perspectives

AbstractDespite the prevailing dominance of lithium‐ion batteries in consumer electronics and electric vehicle markets, the growing apprehension over lithium availability has ignited a quest for alternative high‐energy‐density electrochemical energy storage systems. Rechargeable batteries featuring calcium (Ca) metal as negative electrodes (anodes) present compelling prospects, promising notable advantages in energy density, cost‐effectiveness, and safety. However, unlocking the full potential of rechargeable Ca metal batteries particularly hinges upon the strategic identification or design of high‐energy‐density positive electrode (cathode) materials. This imperative task demands expeditious synthetic routes tailored for their meticulous design. In this Perspective, we mainly highlight the development in the cathode materials for calcium batteries and accentuate the unparalleled promise of solid‐state metathesis routes in designing a diverse array of high‐performance electrode materials.

Evidence of the Electrochemical Ca2+ Intercalation in Anatase Nanotubes

AbstractHere, we demonstrate the electrochemical intercalation of Ca2+ ions within the lattice of anatase nanotubes (a‐NTs) synthesized by hydrothermal treatment of TiO2/NaOH precursors followed by Na+/H+ ion exchange and H2O‐loss at high temperature in air. Scanning electron microscopy, X‐ray diffraction, and Raman spectroscopy confirm the formation of nanosized anatase, whereas transmission electron microscopy highlights the formation of nanotubular morphologies with an average diameter of 10 nm. TiO2 electrodes are able to deliver reversible specific capacities in aprotic batteries vs. calcium metal or in hybrid configurations vs. capacitive activated carbon using aprotic electrolytes (i. e., Ca(BH4)2 in tetrahydrofuran or Ca(TFSI)2 in dimethoxyethane, respectively). The electrochemical intercalation of Ca2+ ions into the anatase lattice is confirmed by X‐ray absorption spectroscopy in close comparison with Na+ and Li+ intercalations. Ca2+ incorporation leads to the partial amorphization of the TiO2 lattice despite the limited Ca/Ti ratio (i. e., 0.09) obtained in discharge. The analysis of the extended X‐ray absorption fine structure region allows the determination of the local structure of the incorporated Ca2+ ions and confirms that a disordered environment is obtained after the electrochemical reaction.

Incorporation of composite metal-PVP derived carbon membranes for the percrystallisation of salt water

In this research using supported metal‑carbon membranes in a membrane percrystallisation application, we investigated the influence of metal ions on the formation of carbon during carbon membrane synthesis by combining polyvinylpyrrolidone (PVP) with various metal compounds, including zinc, potassium, barium, sodium, magnesium, calcium, and strontium, through calcination at 700 °C in a nitrogen atmosphere for the first time. These carbon membranes were then subjected to continuous percrystallisation experiments to produce dry salt crystals from salt solutions. The feed solution (3.5, 10, 20 wt% of salt) were used at 30, 50, and 70 °C for the performance evaluation. Intriguingly, the addition of metal elements to the PVP solution resulted in an enhancement in the total pore volume and surface area of the resulting carbon membranes. The PVP-Zn precursor exhibited the highest increase with a maximum improvement of 99 fold. Moreover, when compared to the PVP membranes alone, the composite membranes also exhibited higher fluxes. Among the tested composite carbon membranes, PVP-Ca, PVP-Zn, and PVP-Mg demonstrated the highest flux values, reaching an impressive 55 kg.m−2.h−1. Additionally, these membranes exhibited self-elimination, where salt was effectively removed from the membrane surface during percrystallisation testing. Thus, these membranes have the potential to be employed in desalination applications.

Biodiesel Prepared Through Silver Doped Blended Heterogeneous Catalyst and Soybean Oil

Biodiesel amalgamate with silver doped nickel and calcium blended oxide catalyst &amp; soybean oil. Alkaline earth metal calcium and the use of nickel blended oxide integrated and optimized throughout a blending process that after silver doped in differing percentages to research the outcome of prepared catalysts on the change oil to FAME. Catalytic characteristics such as surface area, energy band difference, crystallinity, morphology, and the composition of prepared samples explored utilizing different BET, FTIR, XRD, SEM, and EDX methods. Silver doped 20 percent NiO-CaO blended oxide catalyst defined with a distinctive weight percentage of silver 2wt percent Ag found to be most viable with 80 percent transformation of oil. The optimized response variable for the change of biodiesel was alcohol to oil proportion 15:1, response temperature 64oC, and catalytic converter stacking 05wt percent. This prepared catalyst has added significance as a blended catalyst for biodiesel generation. Key Words: FAME, Transesterification, Silver, Mixed Oxide, Catalyst

The durability increasing of high-wear cast parts of mining and processing equipment

The analysis of the operation of rapidly wearing parts of the ore-grinding equipment was carried out. It has been established that unloading grates and ladles are fast-wearing parts of layered fracture mills and determine their downtime between repairs. The possibility of improving the mechanical properties of medium-carbon steel 40HL due to the reduction of harmful impurities is shown. The effects of modification with aluminum, vanadium, calcium, and rare earth metals on structural formation, mechanical, and operational properties of steel are investigated. It was established that the complex modification of cast steel 40HL (0.04…0.1% vanadium, 0.15% silicon calcium and 0.15% rare earth metals) allows to significantly increase its mechanical properties and wear resistance. The separate and joint influence of aluminum, vanadium, calcium and rare metals on the austenite grain size and hardening of steel was studied. The proposed modification technology makes it possible to obtain a fine grain, through-hardening of castings and ensure reliable and long-lasting operation of ball mills.

Chemical and electrochemical reduction of solid oxide fuel

In the present study, the reduction of solid UO2 was performed by chemical and electrochemical reductions in molten calcium salts. All the experiments were conducted at 1123 K. The chemical reduction was performed in molten CaCl2CaF2 by adding calcium metal, while the electrochemical reduction was performed in molten CaCl2CaF2CaO by applying a current from UO2 cathode to graphite anode. By optimizing the experimental conditions, both mechanisms were able to completely reduce the solid UO2 pellet in molten calcium salts. Post-test analyses showed neither uranium in the salt medium nor the intermediate compound on the product (uranium metal) surface.

Effects of multiple metals exposure on abnormal liver function: The mediating role of low-density lipoprotein cholesterol

Equilibration of metal metabolism is critical for normal liver function. Most epidemiological studies have only concentrated on the influence of limited metals. However, the single and synergistic impact of multiple-metal exposures on abnormal liver function (ALF) are still unknown. A cross-sectional study involving 1493 Chinese adults residing in Shenzhen was conducted. Plasma concentrations of 13 metals, including essential metals (calcium, copper, cobalt, iron, magnesium, manganese, molybdenum, zinc, and selenium) and toxic metals (aluminum, cadmium, arsenic, and thallium) were detected by the inductively coupled plasma spectrometry (ICP-MS). ALF was ascertained as any observed abnormality from albumin, alanine transaminase, aspartate transaminase, γ-glutamyl transpeptidase, and direct bilirubin. Diverse statistical methods were used to evaluate the single and mixture effect of metals, as well as the dose-response relationships with ALF risk, respectively. Mediation analysis was conducted to evaluate the role of blood lipids in the relation of metal exposure with ALF. The average age of subjects was 59.7 years, and 56.7 % were females. Logistic regression and the least absolute shrinkage and selection operator (LASSO) penalized regression model consistently suggested that increased levels of arsenic, aluminum, manganese, and cadmium were related to elevated risk of ALF; while magnesium and zinc showed protective effects on ALF (all p-trend < 0.05). The grouped weighted quantile sum (GWQS) regression revealed that the WQS index of essential metals and toxic metals showed significantly negative or positive relationship with ALF, respectively. Aluminum, arsenic, cadmium, and manganese showed linear whilst magnesium and zinc showed non-linear dose-response relationships with ALF risk. Mediation analysis showed that LDL-c mediated 4.41 % and 14.74 % of the relationship of plasma cadmium and manganese with ALF, respectively. In summary, plasma aluminum, arsenic, manganese, cadmium, magnesium, and zinc related with ALF, and LDL-c might underlie the pathogenesis of ALF associated with cadmium and manganese exposure. This study may provide critical public health significances in liver injury prevention and scientific evidence for the establishment of environmental standard.

Highly efficient and air-tolerant calcium-based Birch reduction using mechanochemistry

Abstract In this study, we report a mechanochemical protocol for highly efficient and air-tolerant calcium-based Birch reduction. The developed mechanochemical approach allows the use of readily available calcium metal as a safer-to-handle reductant for Birch reduction of various aromatic compounds. The reaction was rapid and the desired dearomatization products were obtained in good yields within 15 min at ambient temperature. Notably, all synthetic operations can be performed under ambient conditions without a complicated reaction setup involving inert gases. The feasibility of the gram-scale synthesis was demonstrated, further highlighting the practical utility of this protocol.