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64 pages, 12203 KiB  
Review
Beyond Lithium: Future Battery Technologies for Sustainable Energy Storage
by Alan K. X. Tan and Shiladitya Paul
Energies 2024, 17(22), 5768; https://doi.org/10.3390/en17225768 (registering DOI) - 18 Nov 2024
Abstract
Known for their high energy density, lithium-ion batteries have become ubiquitous in today’s technology landscape. However, they face critical challenges in terms of safety, availability, and sustainability. With the increasing global demand for energy, there is a growing need for alternative, efficient, and [...] Read more.
Known for their high energy density, lithium-ion batteries have become ubiquitous in today’s technology landscape. However, they face critical challenges in terms of safety, availability, and sustainability. With the increasing global demand for energy, there is a growing need for alternative, efficient, and sustainable energy storage solutions. This is driving research into non-lithium battery systems. This paper presents a comprehensive literature review on recent advancements in non-lithium battery technologies, specifically sodium-ion, potassium-ion, magnesium-ion, aluminium-ion, zinc-ion, and calcium-ion batteries. By consulting recent peer-reviewed articles and reviews, we examine the key electrochemical properties and underlying chemistry of each battery system. Additionally, we evaluate their safety considerations, environmental sustainability, and recyclability. The reviewed literature highlights the promising potential of non-lithium batteries to address the limitations of lithium-ion batteries, likely to facilitate sustainable and scalable energy storage solutions across diverse applications. Full article
(This article belongs to the Section D: Energy Storage and Application)
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14 pages, 4587 KiB  
Article
Mg/Si- and Ag-Doped Carbon-Based Media Rainwater Filtration System for Multiple Pollutants Removal
by Soyeon Yoon, Hyeseong Kim, Reneesha Valiyaveettil Basheer, Nurhaslina Abd Rahman, Seokbyum Jang, Kientiek Wong, Deokhyun Moon, Choeearn Choong and Min Jang
Materials 2024, 17(22), 5638; https://doi.org/10.3390/ma17225638 (registering DOI) - 18 Nov 2024
Abstract
In this study, the removal performances of a multi-pollutant elimination cartridge system (MPECS) composed of palm shell waste-based activated carbon (PSAC), magnesium (Mg)/silicon (Si)-doped PSAC (Mg/Si-PSAC), and silver (Ag)-doped PSAC (Ag-PSAC) for heavy metals, organic pollutants, and Escherichia coli were investigated. Mg/Si impregnation [...] Read more.
In this study, the removal performances of a multi-pollutant elimination cartridge system (MPECS) composed of palm shell waste-based activated carbon (PSAC), magnesium (Mg)/silicon (Si)-doped PSAC (Mg/Si-PSAC), and silver (Ag)-doped PSAC (Ag-PSAC) for heavy metals, organic pollutants, and Escherichia coli were investigated. Mg/Si impregnation significantly improved heavy metal removal using PSAC by increasing the surface area and adding more sorption sites to the magnesium silicate nanolayer. Fixed-bed column experiments showed that the MPECS column outperformed PSAC and commercial activated carbon (DJAC), with a 1.5 to 2.0 times higher E. coli removal and a higher removal of organic pollutants and heavy metals. The MPECS column, with its disinfection ability and adsorption of heavy metals and organic matter, is a promising system for removing multiple pollutants from rainwater. Full article
15 pages, 4483 KiB  
Article
The Influence of Mg, Na, and Li Oxides on the CO2 Sorption Properties of Natural Zeolite
by Manshuk Mambetova, Kusman Dossumov and Gaukhar Yergaziyeva
Processes 2024, 12(11), 2592; https://doi.org/10.3390/pr12112592 - 18 Nov 2024
Abstract
This study presents a comparative analysis of the CO2 sorption properties of natural zeolites sourced from the Tayzhuzgen (Tg) and Shankanay (Sh) deposits in Kazakhstan. The Tayzhuzgen zeolite was characterized by a Si/Al ratio of 5.6, suggesting partial dealumination, and demonstrated enhanced [...] Read more.
This study presents a comparative analysis of the CO2 sorption properties of natural zeolites sourced from the Tayzhuzgen (Tg) and Shankanay (Sh) deposits in Kazakhstan. The Tayzhuzgen zeolite was characterized by a Si/Al ratio of 5.6, suggesting partial dealumination, and demonstrated enhanced specific surface area following mechanical activation. Modification of the Tayzhuzgen zeolite with magnesium oxide significantly improved its CO2 sorption capacity, reaching 8.46 mmol CO2/g, attributed to the formation of the CaMg(Si2O6) phase and the resulting increase in basic active sites. TPD-CO2 analysis confirmed that MgO/Tg exhibited the highest basicity of the modified samples, further validating its potential for CO2 capture applications. Full article
(This article belongs to the Section Separation Processes)
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11 pages, 7897 KiB  
Article
In Vivo Study of Organ and Tissue Stability According to the Types of Bioresorbable Bone Screws
by Tae-Young Kwon, Geum-Hwa Lee, Hyuk Lee and Kwang-Bok Lee
Materials 2024, 17(22), 5632; https://doi.org/10.3390/ma17225632 (registering DOI) - 18 Nov 2024
Abstract
Biodegradable material, such as magnesium alloy or polylactic acid (PLA), is a promising candidate for orthopedic surgery. The alloying of metals and the addition of rare earths to increase mechanical strength are still questionable in terms of biosafety as absorbent materials. Therefore, the [...] Read more.
Biodegradable material, such as magnesium alloy or polylactic acid (PLA), is a promising candidate for orthopedic surgery. The alloying of metals and the addition of rare earths to increase mechanical strength are still questionable in terms of biosafety as absorbent materials. Therefore, the purpose of this study is to understand the effect of substances due to the degradation of various biodegradable substances on organs in the body or surrounding tissues. A total of eighty male Sprague−Dawley rats were selected for this study, and the animals were divided into four groups. Each of the three experimental groups was implanted with magnesium alloy, polymer, and titanium implants; the control group only drilled into the cortical bone. Serum assay, micro-CT, hematoxylin and eosin staining, immunoblotting, and real-time PCR were evaluated. There was no significant difference between the two groups of magnesium alloy and polymer in serum assay, but micro-CT analysis confirmed that magnesium alloy degrades faster than polymer, and histological examination showed a strong inflammatory response in the early stages, which was similarly observed in immunoblotting and real-time PCR. Our findings show that there was no toxicity due to the degradation of the biodegradable material, and the difference in each inflammatory response is thought to be determined by the rate of degradation in the body. Full article
(This article belongs to the Special Issue Advanced Biomaterials for Medical Applications (2nd Edition))
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12 pages, 4713 KiB  
Article
Liquid Metal Leaching for Rare Earth Magnet Recycling
by Emmanuel Opoku, Chinenye Chinwego, Adam Powell and Brajendra Mishra
Metals 2024, 14(11), 1299; https://doi.org/10.3390/met14111299 - 18 Nov 2024
Viewed by 64
Abstract
This study investigates the optimization of liquid metal leaching for recycling rare earth elements (REEs) from NdFeB magnets, a critical step in addressing the increasing demand for these materials in various high-tech applications. We explored the effects of leaching time, stirring, and magnet [...] Read more.
This study investigates the optimization of liquid metal leaching for recycling rare earth elements (REEs) from NdFeB magnets, a critical step in addressing the increasing demand for these materials in various high-tech applications. We explored the effects of leaching time, stirring, and magnet demagnetization on the yield of the leaching process using molten magnesium. Conducted at 900 °C, our experiments assessed the leaching process over periods of 2, 3.5, and 5 h, with and without the application of stirring. Our findings show that longer leaching times considerably increase neodymium (Nd) and praseodymium (Pr) leaching yield, with a notable peak in efficiency found at 5 h. Stirring improved the uniformity of REEs significantly and resulted in up to 80% yield. Furthermore, our data show that pre-leaching magnet demagnetization improves leaching specificity, significantly reducing the presence of non-target metals like nickel and copper. These insights offer a pathway to more cost-effective recycling of REEs from magnet scrap, which is essential for environmentally conscious management of resources amid the escalating global demand for REEs. Full article
(This article belongs to the Section Extractive Metallurgy)
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11 pages, 1134 KiB  
Article
The Hypothesis of Trace Elements Involvement in the Coronary Arteries Atherosclerotic Plaques’ Location
by Tomasz Urbanowicz, Anetta Hanć, Julia Frąckowiak, Jakub Piecek, Ievgen Spasenenko, Anna Olasińska-Wiśniewska, Beata Krasińska and Andrzej Tykarski
J. Clin. Med. 2024, 13(22), 6933; https://doi.org/10.3390/jcm13226933 (registering DOI) - 18 Nov 2024
Viewed by 59
Abstract
Background: Coronary artery disease (CAD) is a chronic inflammatory disease with multiple well-known risk factors. Although epidemiological studies report improvements in classical CAD risk-factor control, except for diabetes and obesity, cardiovascular diseases remain the leading causes of morbidity and mortality in the [...] Read more.
Background: Coronary artery disease (CAD) is a chronic inflammatory disease with multiple well-known risk factors. Although epidemiological studies report improvements in classical CAD risk-factor control, except for diabetes and obesity, cardiovascular diseases remain the leading causes of morbidity and mortality in the current population. The question regarding the atherosclerotic plaque location in particular arteries remains unanswered. Research on novel possible aspects that could help to properly understand atherosclerosis pathophysiology is essential. This study was based on a body trace-elements analysis, measured in scalp hair samples, as possible co-factors of various enzymes that may be crucial for CAD development. Methods: A total of 133 consecutive male patients with a median age of 71 (65–75) years, who presented with anginal symptoms of CCS class 2.0 (0.3) without previous heart-related interventions, were included in the analysis. The results of the cine-angiography were compared with the demographical, clinical, and laboratory results, followed by scalp-hair trace analysis. The possible predictors for coronary disease locations in the left descending artery (LAD), the circumflex artery (Cx), and the right coronary artery (RCA) were the subjects of this study. Results: Statistically significant differences in the scalp-hair trace elements concentration between the CAD and normal angiogram groups were noticed for magnesium (p = 0.003), calcium (p < 0.001), chromium (p = 0.011), and copper (p = 0.043). The multivariable analysis for epicardial atherosclerotic disease revealed the co-existence of diabetes mellitus (OR: 2.94, 95% CI: 1.27–6.79, p = 0.012) as a possible causative factor for the LAD location. The multivariable analysis for the atherosclerosis location in the Cx artery presented scalp-hair magnesium as a possible predictive factor (OR: 0.98, 95% CI: 0.96–1.00, p = 0.024). The multivariable model for the RCA location of atherosclerotic plaque indicated scalp-hair Zn concentration (0.99, 95% CI: 0.98–1.00, p = 0.002) and serum HDL (OR: 0.61, 95% CI: 0.04–0.09, p = 0.016). Conclusions: Possible hypothetical distinctive pathomechanisms, in particular, coronary artery involvement, in atherosclerosis processes are presented in the male group. Diabetes mellitus was found to be the primary factor for left descending artery disease. The low scalp-hair magnesium concentration was found to be a possible risk factor involved in the circumflex artery atherosclerotic plaque location. The inverse relation between serum high-density lipoprotein, the scalp hair zinc concentration, and right coronary disease was noticed. Full article
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20 pages, 1426 KiB  
Review
Antioxidant Therapy in Neonatal Hypoxic Ischemic Encephalopathy: Adjuvant or Future Alternative to Therapeutic Hypothermia?
by Veronica Notarbartolo, Bintu Ayla Badiane, Vita Maria Angileri, Ettore Piro and Mario Giuffrè
Metabolites 2024, 14(11), 630; https://doi.org/10.3390/metabo14110630 (registering DOI) - 16 Nov 2024
Viewed by 268
Abstract
Background: Oxidative stress-related diseases in newborns arise from pro-oxidant/antioxidant imbalance in both term and preterm neonates. Pro-oxidant/antioxidant imbalance has shown to be present in different pathological conditions such as hypoxic ischemic encephalopathy (HIE), retinopathy of prematurity (ROP), bronchopulmonary dysplasia (BPD), necrotizing enterocolitis (NEC), [...] Read more.
Background: Oxidative stress-related diseases in newborns arise from pro-oxidant/antioxidant imbalance in both term and preterm neonates. Pro-oxidant/antioxidant imbalance has shown to be present in different pathological conditions such as hypoxic ischemic encephalopathy (HIE), retinopathy of prematurity (ROP), bronchopulmonary dysplasia (BPD), necrotizing enterocolitis (NEC), and patent ductus arteriosus (PDA). Methods and Results: We performed a narrative review according to the most recent available literature (2012–2024), using Scopus and PubMed as electronic databases. Many observational and experimental studies in vitro and in vivo have evaluated the effectiveness of antioxidant therapies such as melatonin, erythropoietin (EPO), allopurinol, N-acetylcisteine (NAS), and nitric oxide synthase (NOS) inhibitors in these diseases. Perinatal asphyxia is one of the most important causes of mortality and morbidity in term and near-term newborns. Therapeutic hypothermia (TH) is the gold standard treatment for neonates with moderate-severe perinatal asphyxia, resulting in a reduction in the mortality and neurodevelopmental disability rates. Conclusions: According to the most recent literature and clinical trials, melatonin, allopurinol, NAS, NOS inhibitors, magnesium sulfate, and stem cells stand out as promising as both adjuvants and future probable alternatives to TH in the treatment of HIE. Full article
(This article belongs to the Section Endocrinology and Clinical Metabolic Research)
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20 pages, 20721 KiB  
Article
Investigating Exchange Efficiencies of Sodium and Magnesium to Access Lithium from β-Spodumene and Li-Stuffed β-Quartz (γ-Spodumene)
by Joanne Gamage McEvoy, Yves Thibault and Dominique Duguay
Crystals 2024, 14(11), 988; https://doi.org/10.3390/cryst14110988 (registering DOI) - 16 Nov 2024
Viewed by 262
Abstract
After the high-temperature pretreatment of α-spodumene to induce a phase transition to β-spodumene, a derivative of the silica polymorph keatite, often coexisting with metastable Li-stuffed β-quartz (γ-spodumene), the conventional approach to access lithium is through ion exchange with hydrogen using concentrated sulfuric [...] Read more.
After the high-temperature pretreatment of α-spodumene to induce a phase transition to β-spodumene, a derivative of the silica polymorph keatite, often coexisting with metastable Li-stuffed β-quartz (γ-spodumene), the conventional approach to access lithium is through ion exchange with hydrogen using concentrated sulfuric acid, which presents drawbacks associated with the production of low-value leaching residues. As sodium and magnesium can produce more interesting aluminosilicate byproducts, this study investigates Na+ ↔ Li+ and Mg2+ ↔ 2 Li+ substitution efficiencies in β-spodumene and β-quartz. Thermal annealing at 850 °C of the LiAlSi2O6 silica derivatives mixed with an equimolar proportion of Na endmember glass of equivalent stoichiometry (NaAlSi2O6) indicates that sodium incorporation in β-quartz is limited, whereas the main constraint for not attaining complete growth to a Na0.5Li0.5AlSi2O6 β-spodumene solid solution is co-crystallization of minor nepheline. For similar experiments in the equimolar LiAlSi2O6-Mg0.5AlSi2O6 system, the efficient substitution of Mg for Li is observed in both β-spodumene and β-quartz, consistent with the alkaline earth having an ionic radius closer to lithium than sodium. Ion exchange at lower temperatures was also evaluated by exposing coexisting β-spodumene and β-quartz to molten salts. In NaNO3 at 320 °C, sodium for lithium exchange reaches ≈90% in β-spodumene but less than ≈2% in β-quartz, suggesting that to be an efficient lithium recovery route, the formation of β-quartz during the conversion of α-spodumene needs to be minimized. At 525 °C in a molten MgCl2/KCl medium, although full LiAlSi2O6-Mg0.5AlSi2O6 solid solution is observed in β-quartz, structural constraints restrict the incorporation of magnesium in β-spodumene to a Li0.2Mg0.4AlSi2O6 stoichiometry, limiting lithium recovery to 80%. Full article
(This article belongs to the Collection Topic Collection: Mineralogical Crystallography)
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16 pages, 2408 KiB  
Article
Adaptive Agronomic Strategies for Enhancing Cereal Yield Resilience Under Changing Climate in Poland
by Elżbieta Wójcik-Gront, Dariusz Gozdowski, Rafał Pudełko and Tomasz Lenartowicz
Agronomy 2024, 14(11), 2702; https://doi.org/10.3390/agronomy14112702 - 16 Nov 2024
Viewed by 193
Abstract
Climate-driven changes have raised concerns about their long-term impacts on the yield resilience of cereal crops. This issue is critical in Poland as it affects major cereal crops like winter triticale, spring wheat, winter wheat, spring barley, and winter barley. This study investigates [...] Read more.
Climate-driven changes have raised concerns about their long-term impacts on the yield resilience of cereal crops. This issue is critical in Poland as it affects major cereal crops like winter triticale, spring wheat, winter wheat, spring barley, and winter barley. This study investigates how soil nutrient profiles, fertilization practices, and crop management conditions influence the yield resilience of key cereal crops over a thirteen-year period (2009–2022) in the context of changing climate expressed as varying Climatic Water Balance. Data from 47 locations provided by the Research Centre for Cultivar Testing were analyzed to assess the combined effects of agronomic practices and climate-related water availability on crop performance. Yield outcomes under moderate and enhanced management practices were contrasted using Classification and Regression Trees to evaluate the relationships between yield variations and agronomic factors, including soil pH, nitrogen, phosphorus, potassium fertilization, and levels of phosphorus, potassium, and magnesium in the soil. The study found a downward trend in Climatic Water Balance, highlighting the increasing influence of climate change on regional water resources. Crop yields responded positively to increased agricultural inputs, especially nitrogen. Optimal soil pH and medium phosphorus levels were identified as crucial for maximizing yield. The findings underscore the importance of tailored nutrient management and adaptive strategies to mitigate the adverse effects of climate variability on cereal production. The results provide insights for field crop research and practical approaches to sustain cereal production in changing climatic conditions. Full article
(This article belongs to the Section Agroecology Innovation: Achieving System Resilience)
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14 pages, 1351 KiB  
Article
Movement Behaviors and Bone Biomarkers in Young Pediatric Cancer Survivors: A Cross-Sectional Analysis of the iBoneFIT Project
by Jose J. Gil-Cosano, Esther Ubago-Guisado, Francisco J. Llorente-Cantarero, Andres Marmol-Perez, Andrea Rodriguez-Solana, Juan F. Pascual-Gazquez, Maria E. Mateos, Jose R. Molina-Hurtado, Beatriz Garcia-Fontana, Pedro Henrique Narciso, Panagiota Klentrou and Luis Gracia-Marco
Nutrients 2024, 16(22), 3914; https://doi.org/10.3390/nu16223914 (registering DOI) - 16 Nov 2024
Viewed by 330
Abstract
Background/Objectives: This study aims to investigate the association of movement behaviors with irisin, sclerostin, and bone turnover markers in young pediatric cancer survivors. Methods: A total of 116 young pediatric cancer survivors (12.1 ± 3.3 years; 42% female) were recruited. Time spent in [...] Read more.
Background/Objectives: This study aims to investigate the association of movement behaviors with irisin, sclerostin, and bone turnover markers in young pediatric cancer survivors. Methods: A total of 116 young pediatric cancer survivors (12.1 ± 3.3 years; 42% female) were recruited. Time spent in movement behaviors over at least seven consecutive 24 h periods was measured by accelerometers (wGT3x-BT accelerometer, ActiGraph). Blood samples were collected at rest and serum was analyzed for irisin, sclerostin, cross-linked telopeptide of type I collagen (CTX), procollagen type I amino-terminal propeptide (P1NP), total osteocalcin (OC), alkaline phosphatase (ALP), 25-hydroxyvitamin D, parathyroid hormone (PTH), calcium, phosphorous, and magnesium. Results: Irisin and sclerostin were not significantly correlated with bone turnover markers. Sedentary time was negatively correlated with the P1NP (r = −0.411, p = 0.027) and total OC (r = −0.479, p = 0.015) Z-scores, whereas moderate-to-vigorous physical activity was positively correlated with the P1NP (r = 0.418, p = 0.024) and total OC (r = 0.478, p = 0.016) Z-scores. Moreover, total physical activity was positively correlated with the total OC Z-score (r = 0.448, p = 0.025). Finally, the uncoupling index [CTX/P1NP] was positively correlated with sedentary time (r = 0.424, p = 0.012) and negatively correlated with light physical activity (r = −0.352, 0.041). Conclusions: Reducing sedentary time and increasing physical activity may favor bone formation over resorption in young pediatric cancer survivors. Full article
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20 pages, 1836 KiB  
Article
Effects of Long-Term Nitrogen Fertilization and Application Methods on Fruit Yield, Plant Nutrition, and Soil Chemical Properties in Highbush Blueberries
by Charitha P. A. Jayasinghege, Carine Bineng and Aimé J. Messiga
Horticulturae 2024, 10(11), 1205; https://doi.org/10.3390/horticulturae10111205 - 15 Nov 2024
Viewed by 253
Abstract
Nitrogen (N) fertilizer is routinely applied in highbush blueberry (Vaccinium corymbosum L.) production. The recommended N fertilizer rate increases as the plants mature, and is usually determined based on regional growing conditions. However, the effects of N fertilizer rates and application methods [...] Read more.
Nitrogen (N) fertilizer is routinely applied in highbush blueberry (Vaccinium corymbosum L.) production. The recommended N fertilizer rate increases as the plants mature, and is usually determined based on regional growing conditions. However, the effects of N fertilizer rates and application methods over the long term remain poorly understood. In this study, ammonium sulfate was applied as an N source at the recommended rate (100%), which corresponds to a maximum of 155 kg N ha−1 for plants older than eight years, along with higher rates at 150% and 200% of the recommended level, as well as a control treatment of no N. Treatments were applied to the blueberry cultivar ‘Duke’ as either broadcast (BROAD) or fertigation (FERT), and impacts were analyzed after 12 and 13 years of treatment. In the 14th year, the 100% N rate was uniformly applied as BROAD across all plants to separate the effects of different N rates from those caused by long-term soil condition changes. The BROAD treatment at the 100% N rate achieved the highest yield, and the FERT treatment at 200% resulted in the lowest yield in the 12th year, suggesting that excessive N rates can reduce fruit yield. However, no significant yield differences were observed in the 13th year. Higher N rates were associated with reduced titratable acidity in fruits and fewer flower buds. The soil pH declined across all N treatments, with the FERT at 200% showing the most significant reduction. All N treatments generally increased soil electrical conductivity (EC). High N rates also decreased plant accumulation of magnesium, calcium, and copper, with the latter reaching deficiency levels. These findings emphasize the importance of adhering to recommended N application rates and adjusting soil pH and EC to mitigate the adverse effects of prolonged N treatments. Full article
(This article belongs to the Special Issue Irrigation and Fertilization Management in Horticultural Production)
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22 pages, 13669 KiB  
Article
Equivalent Heat Source Model of Thermal Relay Contact Based on Surface Roughness of Silver–Magnesium–Nickel Contact
by Bo Li, Huimin Liang, Pinmou Li, Yuexian Li and Aobo Wang
Materials 2024, 17(22), 5583; https://doi.org/10.3390/ma17225583 - 15 Nov 2024
Viewed by 262
Abstract
In a sealed electromagnetic relay, the change in the surface roughness mainly depends on the collision wear between the contact and the moving reed and the ablation effect of the arc on the contact surface based on the strong correlation between the contact [...] Read more.
In a sealed electromagnetic relay, the change in the surface roughness mainly depends on the collision wear between the contact and the moving reed and the ablation effect of the arc on the contact surface based on the strong correlation between the contact resistance and the surface roughness of the Ag-Mg-Ni contact. With a change in contact resistance, the contact temperature increase in a hermetically sealed electromagnetic relay (HSER) is greatly affected. Under extreme overload conditions, the contact surface is severely ablated by the arc, and the roughness increases rapidly with the number of cycles, which greatly affects the contact resistance of the contact surface and the reliability of the relay. A thermal model of a relay contact system based on the surface roughness of Ag-Mg-Ni contacts was established in this paper by analyzing the effect of an arc on the surface roughness of Ag-Mg-Ni contacts under heavy overload conditions. The arc image of the Ag-Mg-Ni contact was recorded using a double-axis arc photographing platform, and the moving track of the arc center under overload conditions was drawn. This paper explored the patterns of arc center movement on the contact surface and the effects of the arc on the surface roughness of the contacts by analyzing the probabilities of the arc center appearing in various locations. A mathematical model correlating the number of contact cycles with contact resistance was established. Subsequently, a finite element simulation model for the equivalent heat source of the contact was developed. The theoretical model error was less than 10%. The accuracy of the equivalent heat source model was verified by comparing the measured data with the simulation results. Full article
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16 pages, 7454 KiB  
Article
Dimensional Accuracy After Precision Milling of Magnesium Alloys Using Coated and Uncoated Cutting Tools
by Jarosław Korpysa and Witold Habrat
Materials 2024, 17(22), 5578; https://doi.org/10.3390/ma17225578 - 15 Nov 2024
Viewed by 259
Abstract
Magnesium alloys are an important group of materials that are used in many industries, primarily due to their low weight. Constantly increasing quality requirements make it necessary to improve the accuracy of manufactured products. In this study, the precision milling process for AZ91D [...] Read more.
Magnesium alloys are an important group of materials that are used in many industries, primarily due to their low weight. Constantly increasing quality requirements make it necessary to improve the accuracy of manufactured products. In this study, the precision milling process for AZ91D and AZ31B magnesium alloys was investigated, and the results obtained with uncoated and TiB2-coated end mills were compared. The impact of variable cutting parameters was also investigated. Specifically, the study focused on the dimensional accuracy of the machined parts. The results showed that even though the dimensional accuracy obtained in milling both magnesium alloys was comparable, it was higher in the case of the AZ31B alloy by up to 22%. The study also demonstrated that the use of the TiB2 coating did not have the desired effect and that higher dimensional accuracy up to 27% was obtained with the uncoated tool. Full article
(This article belongs to the Special Issue Non-conventional Machining: Materials and Processes)
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18 pages, 2090 KiB  
Article
From Structure to Strength: Analyzing the Impact of Sulfuric Acid on Pig Bone Demineralization Through FTIR, LIBS, and AAS
by Milica Marković, Miroslav Kuzmanović, Dragan Ranković, Danica Bajuk-Bogdanović, Aleksandra Šajić and Dušan Dimić
Int. J. Mol. Sci. 2024, 25(22), 12250; https://doi.org/10.3390/ijms252212250 - 14 Nov 2024
Viewed by 303
Abstract
The present research aimed to investigate the demineralizing effects of sulfuric acid on pig bone. Alterations in collagen and phosphate contents and changes in the elemental composition of the bone during the 14-day-long immersion in sulfuric acid solutions of different concentrations were estimated [...] Read more.
The present research aimed to investigate the demineralizing effects of sulfuric acid on pig bone. Alterations in collagen and phosphate contents and changes in the elemental composition of the bone during the 14-day-long immersion in sulfuric acid solutions of different concentrations were estimated using ATR-FTIR, LIBS, and AAS. FTIR spectra at amide I (1800–1600 cm−1) and phosphate ν13 (PO43−) (1300–900 cm−1) domains were scrutinized using the deconvolution method for monitoring changes in the protein secondary structure and mineral content. The results implicated sulfuric acid as a powerful demineralization agent and effective in targeting mineral components, such as hydroxyapatite, while leaving the collagen matrix relatively preserved with a complex secondary structure. Collagen maturity marker values gave valuable insights into the structural integrity of the bone. LIBS and AAS indicated changes in bone hardness; phosphorous-to-carbon ratio; and calcium, phosphorous, and magnesium content in the solutions left after the immersion period. The changes in the ratio of ionic-to-atomic calcium lines in the LIBS spectra indicated hardening of the bone, with increasing acid concentration and prolonged action, due to the deposition of calcium sulfate on the surface. The calcium concentration in the solutions decreased with increased acid concentration, while the change in phosphorus and magnesium concentrations was reversed. Full article
(This article belongs to the Special Issue Molecular Updates and Applications in Forensic Medicine)
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18 pages, 6817 KiB  
Article
Comparative Analysis of Nutrients, Phytochemicals, and Minerals in Colored Sweet Potato (Ipomoea batatas L.) Roots
by Shan Zhao, Lingli Zhong, Xi Li, Lin Qin, Ya Zhou, Xinyu Lei, Xingguo Zheng, Keting Jin, Zhigang Pu, Xue Hou, Jun Song, Tao Lang, Cong Zhang and Junyan Feng
Foods 2024, 13(22), 3636; https://doi.org/10.3390/foods13223636 - 14 Nov 2024
Viewed by 342
Abstract
Sweet potato (Ipomoea batatas (L.) is regarded among the most crucial crops globally because it is abundant in essential nutrients vital for human health. However, limited comprehensive information is available regarding the nutritional composition of sweet potato, which hinders its optimal utilization. [...] Read more.
Sweet potato (Ipomoea batatas (L.) is regarded among the most crucial crops globally because it is abundant in essential nutrients vital for human health. However, limited comprehensive information is available regarding the nutritional composition of sweet potato, which hinders its optimal utilization. This study investigated the nutritional and chemical composition of sweet potato roots and explored their interrelationships. In total, 86 sweet potato accessions, comprising white, yellow, orange, and purple flesh-colored varieties, were used. A total of 34 components, including nutrients, phytochemicals, and minerals, were identified. Multivariate analysis was performed to assess the relationships among these components. The sweet potato roots were rich in carbohydrates, polyphenols, and minerals. Carbohydrates were primarily composed of total starch (22.6–69.7 g/100 g DW), total soluble sugar (TSS) (10.3–40.0 g/100 g DW), and total dietary fiber (TDF) (7.99–26.0 g/100 g DW). Polyphenols included total caffeoylquinic acids (CQAs) (0.478–14.2 g/kg DW), total anthocyanins (0–2003 mg/kg DW), and β-carotene (0–133 mg/kg DW). The mineral content followed the order: potassium > calcium > phosphorus > sodium > magnesium > iron > manganese > zinc > copper > selenium. White-fleshed sweet potato exhibited high total starch levels (50.4 g/100 g DW) but low TSS levels (21.1 g/100 g DW). Orange-fleshed sweet potato contained high levels of TSS (26.5 g/100 g DW), TDF (17.9 g/100 g DW), and β-carotene (61.4 mg/100 g DW) but low levels of protein (2.99 g/100 g DW) and total starch (43.0 g/100 g DW). Purple-fleshed sweet potato had high levels of phytochemicals, particularly total CQAs (8.17 g/kg DW) and anthocyanins (904 mg/kg DW). Cluster analysis categorized sweet potato accessions into six clusters with unique characteristics. Furthermore, principal component analysis identified accessions with exceptionally high nutritional content. The correlation analysis indicated that starch was negatively correlated with soluble sugar and TDF, whereas CQAs and anthocyanins were highly positively correlated. These findings offer a solid theoretical foundation for sweet potato breeding and utilization. Full article
(This article belongs to the Section Food Nutrition)
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