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Effect assessments of metals are mostly based on single‐metal, single‐species tests, thereby ignoring metal‐mixture effects and indirect effects through species interactions. We tested the combined effects of metal and species interactions in two‐trophic algal–daphnid microcosms. Metal‐mixture effects on daphnid communities may propagate from effects on the generally more sensitive algal communities. Four different algal communities (three species each), with and without addition of the same daphnid community (three species) were exposed to single metals and one metal mixture (17:17:51 µg/L Ni:Cu:Zn). Daphnid densities were negatively affected by metals in the two‐trophic test, the magnitude of which depended on the algal community composition. Algal densities were overall positively affected by the metals in the two‐trophic test but negatively in the single‐trophic test, illustrating an indirect positive effect in the two‐trophic system due to a reduced grazing pressure. Metal effects on daphnid communities in the two‐trophic test (day 21) were correlated with metal effects on the single‐trophic–level algal communities during exponential growth (R2 = 0.55, p = 0.0011). This finding suggests that metal effects propagate across trophic levels due to a reduced food quantity. However, the indirect positive effects on algal densities, resulting in abundant food quantity, suggests that metal effects can also propagate to daphnids due to a reduced food quality (not measured directly). Metal‐mixture interactions on daphnid densities varied during exposure, but were additive or antagonistic relative to independent action when final daphnid densities were considered (day 56). This suggests stronger indirect effects of the mixture compared with the single metals. Overall, our study highlights the dynamic aspect of community‐level effects, which empirical reference models such as independent action or concentration addition cannot predict. Environ Toxicol Chem 2024;00:1–15. © 2024 SETAC [ABSTRACT FROM AUTHOR]

Nominally, meso-hydroxyoxochlorins, like known 5-hydroxy-7-oxo-octaethylchlorin (9), its nickel complex [5-hydroxy-7-oxo-octaethylchlorinato]nickel(II) (9Ni), or the novel 5-hydroxy-7,17-dioxo-octaethylbacteriochlorin (10), incorporate an acetylacetonate (acac)-moiety in the enol form in their chromophore structures. X-Ray diffraction studies of the compounds show the presence of a strong H-bond between the enol and flanking β-ketone. Like acac, the functionality can be deprotonated. However, unlike regular acac-like moieties, we did not find any indication that this functionality is competent in chelating any of the 3d or 4d transition metal ions tested. Evidently, the conjugation that contributes to the stability of acac as a ligand cannot be expressed in the meso-hydroxyoxochlorins since it would perturb the aromaticity of the porphyrinic chromophores; in other words, the metal binding energies do not offset the loss in aromaticity. The halochromic properties of the molecules provide some more insight into the location of the protonation/deprotonation sites. The interpretation of the findings is supported by computations. [ABSTRACT FROM AUTHOR]

The hydraulic bulge test with micro-samples is expected to be useful in the damage assessment of long-service-period metals to understand the degeneration of their mechanical properties. Since the hydraulic bulge test has a different stress state from the classical uniaxial tensile test, we need to understand their correlation and differences. In this study, the hydraulic bulge test and the uniaxial tensile test are employed to analyze the mechanical properties of three typical metals used in pressure vessels: 316L, 16MnDR, and Q345R. By utilizing Kruglov's vertex thickness and Panknin's curvature radius equivalent, the pressure–displacement curves from the hydraulic bulge test are converted into biaxial stress–strain curves. Based on the equivalent plastic energy model, the biaxial stress–strain curves are converted into uniaxial stress–strain curves with an error less than 10% in the strain hardening stage, achieving the unified characterization of mechanical properties under different stress states. Moreover, the hydraulic bulge test provides a more extensive strain hardening stage, and the fracture strains are 9–16.5% larger than those of uniaxial tensile test. This paper provides a reference for using the hydraulic bulge test with micro-samples in studying the mechanical properties and presents the advantages of this novel test method. [ABSTRACT FROM AUTHOR]

For the determination of tin(II) traces, an extractive spectrophotometric approach is devised. The applied method serves a powerful tool for determination of tin(II), involves the formation of yellow colored complex after the binding of 6-bromo-3-hydroxy-2-(5-methylfuran-2-yl)-4H-chromen-4-one (BHMF) and tin(II) in 1:2 stiochiometry in a slightly acidic medium (HCl). The complex shows absorbance at 434 nm with respect of the blank reagent. The outcomes of spectral investigation for complexation showed a Beer's range of 0–1.3 μg Sn mL−1, molar absorptivity, specific absorptivity and Sandell's complex sensitivity are 9.291 × 104 L mol−1 cm−1, 0.490 mL g−1 cm−1 and 0.002040 μg cm−2 at 434 nm that was stable for two days. The interferences study results showed that this method is free from interferences, when tested with metal ions including Ag, Be, Bi, Ca, Cd, Ce, Co, Hg, Mo, Re, Pt, Se,Ti, U, V, W and other common cations, anions, and complexing agents. The applied method is quite simple, highly selective, and sensitive with good re-producibility. This method has been satisfactorily by utilizing the proposed procedure, and its applicability has been tested by analyzing synthetic samples and an alloy sample of gunmetal. The procedure assumes this because of the scarcity of better methods for determining tin(II). The results are in good agreement with the certified value. [ABSTRACT FROM AUTHOR]

Green surfactants have significant potential for improving environmental remediation methods. The aim of the present study was to formulate a green natural detergent containing the biosurfactant produced by Starmerella bombicola ATCC 22214 grown in 1.2% canola oil, 10% sucrose, and 0.5% corn steep liquor. The biosurfactant reduced surface tension to 31.84 mN/m and was produced at a yield of 22 g/L. Twelve formulations were proposed using cottonseed oil as the natural solvent and different stabilisers (vegetable wax, hydroxyethyl cellulose, and sodium alginate). The detergent was evaluated for its emulsifying capacity and stability over a 10-day period. Ecotoxicity was investigated using the marine recruitment test on metal plates covered with paint into which the biosurfactant was incorporated as well as tests with a microcrustacean and vegetable seeds. The formulation designated H, consisting of 1% biosurfactant, 40% cottonseed oil, and 2% hydroxyethyl cellulose, achieved the best results. The formulation exhibited both stability and emulsifying capacity (100% of petroleum). The ecotoxicity tests revealed the safety of the natural detergent. The detergent achieved satisfactory oil dispersion and solubilised 98% of the oil impregnated on the rock. The results indicate that the natural detergent holds promise for efficiently cleaning up environmental areas contaminated with oil and petroleum products. [ABSTRACT FROM AUTHOR]

Fracture resistance is an important parameter used to predict the performance of indirect dental restorations. The purpose of this in vitro study was to assess the fracture load of posterior milled nanoceramic crowns, in comparison with the lithium disilicate crowns, after fatigue loading, for two different restoration occlusal thicknesses. Forty test metal dies were fabricated by duplicating a master metal model consisting of an anatomic abutment preparation of the maxillary first premolar for a single crown. The dies were divided into two groups of 20 each for the fabrication of nanoceramic (Lava Ultimate) and lithium disilicate (IPS e.max CAD) single crowns. Each material group was further divided into two sub-groups of 10 dies each, based on crown occlusal thickness, of 0.5-mm and 0.75-mm (n = 10). Dental Type V stone dies poured from polyvinyl siloxane impressions of the test metal dies were laboratory scanned in order to design and mill 40 ceramic crowns. The crowns were cemented on to the test metal dies with a self-adhesive resin luting cement. All crowns were thermocycled (2500 cycles) and mechanically loaded (250,000 cycles) in a chewing simulator followed by static loading until failure, and the values noted. The data were statistically analyzed by 2-way ANOVA and Tukey HSD post-hoc multiple comparison tests (α = 0.05). The mean fracture loads ranged from 1022 to 1322 N for nanoceramic crowns and from 1145 to 1441 N for the lithium disilicate crowns. Two-way ANOVA revealed insignificant differences between the nanoceramic and lithium disilicate crowns (p > 0.05) in terms of fracture load. Significant differences were noted in the fracture resistance of crowns based on occlusal thickness (303 N; p = 0.013) regardless of the material used. Multiple comparisons by Tukey HSD post-hoc test showed insignificant differences between the four material-occlusal thickness groups (p > 0.05). The nanoceramic crowns were found to be comparable with lithium disilicate crowns in terms of fracture load. The mean fracture loads of all of the tested crowns were within the normal physiological masticatory load limits. Based on the fracture-resistance results, nanoceramic crowns seem to be suitable for clinical use for the tested occlusal thicknesses. [ABSTRACT FROM AUTHOR]

Today, bran is considered a functional compound in the food industry. The aim study was to investigate different processing methods of rice bran to improve its physicochemical characteristics. Treatments were prepared in 12 groups, control (C0), 4 samples hydrothermal treated H1 and H2 (1 and 2 h at 30 °C, respectively), H3 and H4 (1 and 2 h at 80 °C, respectively), 4 samples microwave treated M1 and M2 (4 and 7 min at a 600 w, respectively), M3 and M4 ((4 and 7 min at a 600 w, respectively), 4 samples hydrothermal -microwave treated HM1 and HM2 (First, 1 and 2 h at 50 °C, respectively, then 4 min at 750 w), HM3 and HM4 (First, 1 and 2 h at 50 °C, respectively, then 7 min at 750 w). The results showed that the hydrothermal - microwave method was more effective in reducing phytic acid than the other two methods (p<0.05) so the HM4 treatment had the lowest amount of phytic acid (p<0.05). The color value test showed the lowest ΔE change was related to rice bran hydrothermal treated (H1 with ΔE equal to 6.36) (p<0.05). The hydrothermal -microwave process showed the highest retention of iron, zinc, and calcium (p<0.05). Most minerals were shown in HM1 (6.68, 1.56, and 106.43 ppm, respectively). The heavy metals test indicated that in all treatments, the number of heavy metals significantly decreased compared to the control (p<0.05). However, the microwave method was more effective than others (p<0.05). Therefore, it can be concluded that using the hydrothermal -microwave method provides better quality rice bran. [ABSTRACT FROM AUTHOR]

In this work, the phytochemical composition and the biological activity of the ethanolic extracts obtained from Ajuga reptans L. (Lamiaceae) leaves and roots (growing in Lesser Poland Voivodeship, Poland) were compared. The phytochemical composition of the extracts were determined by the high-performance liquid chromatography with diode-array detection (HPLC–DAD) method. The dominant compounds in both extracts were verbacoside, isoverbacoside, 3,4-dihydroxyphenylacetic acid and rosmarinic acid. The antioxidant capacity of the extracts was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and 2,2'-azobis(3-ethylbenzothiazoline-6-sulfonate (ABTS) tests. The Folin–Ciocalteu assay was used to determine the total polyphenolic content. Additionally, enzyme (tyrosinase, collagenase) inhibition tests and metal chelating ability were studied to assess the anti-aging properties of the extracts. Moreover, the A. reptans extracts' capacity to absorb the whole range of ultraviolet radiation and high-energy visible (HEV) light was evaluated. The skin irritation test (SIT) EpiDerm was applied to evaluate the safety of the bugle extracts. The noteworthy point is that there is a lack of literature on the assessment of A. reptans root extract activity. Our study is the only one that compares the quantitative composition and biological activity of extracts from the root and leaves of A. reptans. The obtained results indicated that both of the extracts exhibit high antioxidant, chelating and photoprotective activity, but the extract from A. reptans roots showed a higher enzyme inhibition effect for mature skin. The A. reptans root extract, similarly to the leaf extract, could be applied as potentially multi-functional, safe and sensitive cosmetic raw materials, especially in anti-aging and anti-pollution cosmetics. [ABSTRACT FROM AUTHOR]

Generally, brazing is completed when the brazing filler metal permeates the gap by uniform wetting. It is believed that the joining process is completed with the formation of joint defects 'voids' in the process of uniform wetting. However, previous studies have shown that what occurs when brazing is performed is non-uniform wetting. It is suggested that this non-uniform wetting is the cause of void generation. Wetting and spreading of brazing filler metal is tested on a metal plate, as described in JIS Z 3191. This is used to investigate the wetting of the brazing filler metal. However, this method does not cover the wetting of the molten brazing filler metal as it moves into the gap. Therefore, it is suggested that the JIS Z 3191 experiment is insufficient to evaluate the wetting of the molten brazing filler metal that penetrates into the gap. In this experiment, we created new specimen. It is called us 'V-groove specimen'. Specimens were created with two base metals. They are pure copper and lead-free brass in which bismuth was used as an alternative element. In order to do in situ experiments, it was not possible to observe the inside of a conventional electric furnace. Therefore, we produced a furnace with a window for in-situ observation and experimented with it. As a result of experiments with V-groove specimens, it was found that there are two types of wetting of brazing filler metal. They are called 'primary wetting' and 'secondary wetting'. The shape of the specimen was measured and evaluated for two types of wetting. The results showed that the primary wetting was measurable in shape and spread evenly. However, the shape of the secondary wetting could not be measured, and it was found to be non-uniformly spread. [ABSTRACT FROM AUTHOR]

Continuous wave EPR spectroscopy at 35 GHz is an essential cornerstone in multi-frequency EPR studies and crucial for differentiating multiple species in complex systems due to the improved g tensor resolution compared to lower microwave frequencies. Especially for unstable and highly sensitive paramagnetic centers the reliability of the measurements can be improved by the use of a single sample for EPR experiments at all frequencies. Besides the advantages, the lack of common availability of oversized-sample resonators at 35 GHz often limits scientists to lower frequencies or smaller sample geometries, the latter may be non-trivial for sensitive materials. In this work, we present the design and performance of an oversized-sample 35 GHz EPR resonator with a high loaded Q value up to 3300 well suited for continuous wave EPR and single microwave frequency experiments with low excitation power. The design is driven by electromagnetic field simulations and the microwave characteristics of manufactured prototypes were found in agreement with the predictions. The resonator is based on a cylindrical cavity with a TE011 mode allowing for 3 mm sample access. Design targets met comprise high sensitivity, robustness, ease of manufacturing and maintenance. The resonator is compatible with commercial EPR spectrometers and cryostats, allowing for measurements at temperatures down to at least 4 K. To highlight the general applicability, the resonator was tested on metal centers as well as on organic radicals featuring extremely narrow lines. [ABSTRACT FROM AUTHOR]

In order to predict the shelf life of non-ferrous metals, laboratory studies into the kinetics of corrosion processes of metals under various temperature and humidity conditions were performed. The results of 12-month corrosion tests of the following non-ferrous metals are presented: aluminum, cobalt, copper, nickel, tin, lead, and zinc at various relative humidity and air temperature conditions. All the metals studied were found to be corrosion-resistant under atmospheric conditions at a relative humidity of no more than 80% and an air temperature of no more than 30 °C. An increase in air humidity from 70 to 95% and air temperature from 20 to 50 °C leads to an increase in corrosion-induced losses of metals, primarily for zinc, cobalt, and lead. During the tests, changes in the appearance of the sample surface were recorded. The chemical and phase composition of oxide films on the metal surface, as well as their morphology, were studied after different test periods. The results will be used in future works in developing methods for predicting the shelf life of non-ferrous metals. [ABSTRACT FROM AUTHOR]

Century eggs (also known as pídàn) are a widely used preserved food product in Taiwanese cuisine. Due to their peculiar appearance, pungent odor, and unusual texture, several consumers have raised concerns. Actually, some metallic additives are employed to control the quality of gelation of protein during the production of century eggs. Therefore, a method involving microwave plasma-atomic emission spectrometer and microwave-assisted digestion was proposed in this study. In addition, to clarify distribution information of metallic additives in century eggs, detailed analyses based on the egg structure were adopted. The linearities for Fe and Zn were obtained in the range of 0.1-5, and 0.02-1 mg L-1 for Cu and Pb. The method detection limits for test metals were 0.06-0.036 mg L-1. The measured values for the RM EGGS-1 sample agreed reasonably well with the reference values, demonstrating that the developed method is practical for routine analysis with lower instrument procurement/running cost. The analytical results for century eggs collected from local markets revealed diverse distributions of metal ions in different parts. Remarkably, this method can readily identify the metallic additives used during the production processes even in the presence of complicated matrices. [ABSTRACT FROM AUTHOR]

Quorum quenching (QQ) is an efficient way to mitigate membrane biofouling in a membrane bioreactor (MBR) during wastewater treatment. A QQ bacterium, Lysinibacillus sp. A4, was isolated and used to mitigate biofouling in an MBR during the treatment of wastewater containing metals. A QQ enzyme (named AilY) was cloned from A4 and identified as a metallo-β-lactamase-like lactonase. The QQ activity of A4 and that of Escherichia coli BL21 (DE3) overexpressing AilY could be promoted by Fe2+, Mn2+, and Zn2+ while remaining unaffected by other metals tested. The two bacteria effectively mitigated biofouling by reducing the transmembrane pressure from around 30 to 20 kPa without negative influence on the COD, NH4+-N, or total phosphorus of the effluent. The relative abundance of Lysinibacillus sp. A4 increased greatly from 0.04 to 8.29% in the MBR with metal-containing wastewater, suggesting that Lysinibacillus sp. A4 could multiply quickly and adapt to this environment. Taken together, the findings suggested that A4 could tolerate metal to a certain degree, and this property could allow A4 to adapt well to metal-containing wastewater, making it a valuable strain for mitigating biofouling in MBR during the treatment of metal-containing wastewater. [ABSTRACT FROM AUTHOR]

During the manufacturing and service of thin metal sheets, different stress states occur, often caused by non-proportional loading conditions. They can lead to localization of inelastic deformations as well as to damage and failure processes. In the present paper, a series of experiments with newly designed biaxially loaded specimens is presented to analyze the damage and failure behavior of thin ductile metal sheets under non-proportional load paths. Bands of holes with different orientation have been milled in critical regions of the specimens to localize stresses and strains. In compression tests, a special downholder is used to avoid buckling. During the loading processes, strain fields in critical regions of the specimens are monitored by digital image correlation technique. After the experiments, fracture surfaces are investigated by scanning electron microscopy showing different damage and fracture modes depending on the loading history. The experiments clearly demonstrate the efficiency of the thin specimens and the experimental program. [ABSTRACT FROM AUTHOR]

The corrosion damage of an epoxy coating/metal system was accelerated by different cyclic tests. Electrochemical impedance spectroscopy (EIS), optical microscopy, laser microscopy, adhesion measurement, scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) were employed to reveal the degradation processes of the coating/metal system in these tests. The results showed that the test of cyclic polarization in immersion dramatically accelerated the corrosion of the metallic substrate. It is interesting that the alternating simple immersion and UV irradiation could slightly retard the coating damage in the first 15 days, whereas the alternating UV irradiation in air and electrochemical polarization in immersion could speed up the damage, which might better simulate the degradation of the coating/steel system in the marine tidal zone. [ABSTRACT FROM AUTHOR]

Using the created experimental equipment for testing metals by the method of instrumented indentation, a procedure for determining Brinell hardness during the nondestructive testing of structural elements has been developed. In contrast to the conventional method, the hardness is determined by the proposed procedure using the proportionality parameter of plastic indentation, a, which is equal to the slope of the instrumented indentation diagram in the coordinates maximum force of cycle Fmax – residual indentation depth hp after removing the test load of this cycle. Based on the results of a series of tests by the method of instrumented indentation of hardness standards, a linear correlation dependence was obtained between the Brinell hardness value and the proportionality parameter of plastic indentation in a wide range of measured hardness values of 110–650 HBW. The peculiarities of using this procedure and its limitations are analyzed on a number of structural carbon, heat-resistant, and high-strength steels. It is shown that the Brinell hardness measurement results, obtained by the improved procedure, agree within the permissible error with the results of the conventional DSTU ISO 6506-1:2019 method. The difference between their values does not exceed 3.9%. The presented improved procedure can be used in the laboratories of research and educational institutes, central factory laboratories and specialized divisions of various subordination, and other organizations involved in monitoring the condition of the operating critical equipment and setting its further service life both in the laboratory and in the field. [ABSTRACT FROM AUTHOR]

In order to improve the adsorption capacity of waste-based ceramsite, this study proposed to use acid-alkali surface modification to enhance the adsorption capacity of ceramsite for heavy metals. In acid treatment, the ceramsite surface generated a composite pore structure, thus the specific surface area of ceramsite is significantly increased through acid treatment. In alkaline treatment, hydroxyl functional groups were loaded on the surface of the ceramsite, therefore the adsorption capacity for heavy metals was significantly improved. The surface of modified ceramic particles carries a negative charge, which is beneficial for the adsorption of cations. Taking lead ions as an example, the adsorption performance of ceramic particles on heavy metals was tested, and the maximum adsorption capacity reached 33.2 mg/g. Furthermore, the modified ceramic particles exhibit good desorption and regeneration properties. The modified ceramsite offers advantages in terms of raw material sources and production costs compared to natural zeolite. [ABSTRACT FROM AUTHOR]

Malaysian herbs, Averrhoa Bilimbi, and Flos Lonicerae, are widely known in traditional Chinese medicine. Both are used as natural remedies for jaundice treatment in newborns. Formulating herbal bath soap by the saponification method is proposed because newborn babies are poor feeders. Today, a lot of chemicals are used in soap production. Users will have a wide range of issues due to chemicals like parabens and triclosan. As a result, soap is made from herbs without chemicals. This herbal soap uses two herbs, Averrhoa Bilimbi leaf and Flos Lonicerae. Paper journals examining these herbs’ physicochemical properties are scarce in Malaysia. After the herbal soap has been successfully created, it will be examined for its physicochemical properties. The antioxidant activity and total phenolic content (TPC), of Averrhoa Bilimbi leaf extract and Flos Lonicerae extract were all tested. The antibacterial activity, heavy metal and pH tests were also validated the suitability of this herbal soap for skin application. According to the findings, Averrhoa Bilimbi leaf extract had a TPC value of 24.49 mg GAE/g compared to 4.96 mg GAE/g for Flos Lonicerae extract. Averrhoa Bilimbi leaf required a slightly higher concentration of 0.0588 g/mL extract to inhibit 50% of the DPPH assay compared to Flos Lonicerae plant extract, which required 0.0315 g/mL. Since there was no evidence of any bacterial growth, the herbal soap was effective against all the tested bacterial strains. The heavy metal test showed the soap does not contain any lead, mercury or arsenic and exhibits a pH value which close to the range for suitable skin application. [ABSTRACT FROM AUTHOR]

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Introduction: Prolonged exposure to a complete button battery can cause severe tissue necrosis in the eye and permanent impairment of visual function. The main mechanism of injury is the current generated by the hydrolysis of tissue fluid at the negative electrode and the production of hydroxide ions. Case Presentation: A 3-year-old girl went to the local hospital because of swelling and pain in her right eye of 12-h duration. The local doctor performed an orbital CT (computed tomography) scan and found a foreign body between the right eyelid and the eyeball. The foreign body was removed immediately under general anesthesia. In addition, it was found that the foreign body was a button battery, but it prolonged 39 h from the onset of the child's symptoms. The child underwent a second operation in our hospital and received amniotic membrane transplantation combined with conjunctival flap coverage. Topical corticosteroid and antibiotic eye ointment were continued for 3 months after surgery. Local pigmentation was seen, there was no symblepharon, but the cornea was still opaque and the visual acuity was only FC (finger count). In this particular case, heavy metal testing conducted on the child's blood fortunately revealed that the levels were within the normal range. Conclusion: Early detection and urgent removal of button battery are crucial in order to minimize exposure time. We should also be concerned about heavy metals in the blood. Children should be kept away from button batteries as much as possible to avoid such injury. [ABSTRACT FROM AUTHOR]

This article explores the rarity of green haüyne gemstones, which are typically known for their blue color. However, greenish blue and green variations have been discovered in Afghanistan and Tanzania. The Gems and Precious Metal Testing Laboratory of the Gem and Jewelry Institute of Thailand examined seven green haüyne gemstones, confirming their haüyne properties. The article provides a scientific analysis of the gemstones' physical properties, microscopic observations, and chemical analyses. This study is the first to describe gem-quality green haüyne. [Extracted from the article]

On a worldwide scale, A. cepa is among the most commonly consumed vegetables. In Europe, the leading onion producers are Russia, the Netherlands, Spain, Poland and Germany. In this study, the bioaccumulation of heavy metals (Cr, Cu, Zn, Ni, Fe, Mn, Co, Sr, Cd and Pb) by Allium cepa L. plants was followed under hydroponic conditions. The heavy metals were applied at six concentrations (0, 25, 50, 100, 200 and 400 mg L−1) over three weeks. The quantitative analysis of selected heavy metals in plant tissues (bulbs, roots and assimilation leaves) was performed using atomic absorption spectrometry with flame atomization (F-AAS). The accumulation of metal ions was strongly dependent on their concentrations in the solution and the analyzed parts of plants. The highest accumulation of metal ions was confirmed for the roots and ranged from 8.48 to 5912.34 µg g−1 DW (dry weight). All parts of A. cepa were characterized by the high accumulation of Mn2+. The lowest accumulation was confirmed for Co2+ in the roots, Pb2+ in the assimilation leaves and Cu2+ in the bulbs of onion. Moreover, the study showed that the highest concentrations of heavy metals decreased the growth of bulbs and even caused them to die off. In contrast, lower concentrations of some elements stimulated plant development. [ABSTRACT FROM AUTHOR]

There are high demands for the early and reliable detection of metal components used in safety-critical structures. Nondestructive testing (NDT) is a pivotal technique used across industries to assess a material's integrity without causing damage and has been used in early crack detection of metals, mainly based on changes in the crystal structure and magnetic properties of metals. This review provides an overview of internal and external detection technology based on nondestructive testing methods such as ultrasonic, electromagnetic, ray, magnetic particle, etc. Especially, the integration of advanced methodologies such as machine learning and artificial intelligence deserves a place in NDT methods. Furthermore, the multifactorial detection method is promoted to enhance the sensitivity and detection range due to advantage integration but still has emerging challenges for safer equipment and applications. The review aims to compare these methods and outline the future challenges of NDT technologies for metal crack detection. [ABSTRACT FROM AUTHOR]

The present study was undertaken to determine / assess the contamination of heavy metals in different six sites of Narmada River in Jabalpur region. The study was conducted during September, 2022 to February, 2023. Water samples of different Sites A to F were also assessed for presence of heavy metals by spot test. The results indicated the presence of heavy metals (Lead, Copper and Mercury) in the sites B and C. Results showed poor water quality of these sites due to the different anthropogenic activities. Twenty-four fishes (Nile tilapia, Oreochromis niloticus) were collected from different sites for histopathological study. Liver tissues were collected from all fishes. The liver tissues of fishes showed normal structure in control group (Site A). In the fishes of Site B, the liver showed necrosis of hepatocytes and vascular degenerations. In the fishes of Site C, the liver tissues showed hydropic vacuolation and necrosis. In the fishes of Site D, the liver sections showed congestion and central vein nuclear pyknosis. However, the liver tissue showed vacuolation, degenerative and necrotic changes in the fishes of Site E. Similarly, the liver tissues showed degenerations of hepatocytes and intravascular haemolysis in blood vessels in the fishes of Site F. [ABSTRACT FROM AUTHOR]

The laminated metal materials are widely used in military, automobile and aerospace industries, but their dynamic response mechanical behavior needs to be further clarified, especially for materials with joint interface paralleling to the loading direction. The mechanical properties of TA2/Q345 (Titanium/Steel) laminated metal of this structure were studied by using the split Hopkinson pressure bar (SHPB). To shed light on the stress-state of a laminated metal with parallel structure, the relative non-uniformity of internal stress R(t) was analyzed. The mechanism of deformation compatibility of welding interface was discussed in detail. The current experiments demonstrate that in the strain rate range of 931–2250 s−1, the discrepancies of the internal stress in specimens are less than 5%, so the stress-state equilibrium hypothesis is satisfied during the effective loading time. Therefore, it is reasonable to believe that all stress–strain responses of the material are valid and reliable. Furthermore, the four deformation stages, i.e., the elastic stage, the plastic modulus compatible deformation stage, uniform plastic deformation stage and non-uniform plastic deformation stage, of the laminated metal with parallel structure were firstly proposed under the modulating action of the welding interface. The deformation stages are helpful for better utilization of laminated materials. [ABSTRACT FROM AUTHOR]

Increasing pollution in the environment calls for the precise determination of metal toxicity in plants as they are at the base of the food chain. Mosses are often employed as biomonitors and provide good models for testing metal adsorption. However, species may react differently and many studies only look at one metal at a time, even though toxicity levels are affected by metal combinations. In this study, the effects of CuCl2, MnCl2, FeCl2, and Sb-acetate were examined individually and in combinations on the moss species Pohlia drummondii and Physcomitrium patens. In general, the two species reacted differently to the presence of trace metals; although, for both, the tolerance limit was at 100 µM. Overall, individual metals were less toxic than combinations, with some exceptions for Fe and Mn in P. patens. Additionally, we demonstrate that multiple combinations of metals are especially toxic if Cu is present. [ABSTRACT FROM AUTHOR]

This study is conducted to determine the extent to which transfer stations in the Karkh neighborhood of Baghdad, Iraq, contribute to physicochemical and heavy-metal contamination of the soils in the immediate area. The concentrations of physicochemical primary indicators (pH, OC, OM, Ca+2, Mg+2, Na+1, NO3 -1, Cl-1, SO4 -2) and heavy metals (Pb, Cd, and Cu) were measured during July 2022 at four investigation sites that were located at distances of 5 m (Site 1), 10 m (Site 2), 15 m (Site 3), and 20 m (Site 4) from the edges of the mentioned transfer stations (Al-Rasheed, Al-Mansour, Al-Shula, and AlDora). The concentrations of the physico-chemicals and heavy metals were compared to the standards of the Food and Agriculture Organization (FAO) and the Consensus-Based Sediment Quality Guidelines (CBSQG). Based on the data collected, it was determined that Site 1 had the greatest physico-chemical and heavy metal concentrations, whereas Site 4 had the lowest. The metals tested were found to accumulate in the following order: Cu > Pb > Cd. Additionally, it was noticed that all the measured concentrations of metals were higher than the limitations of the CBSQG. The presence of Ca+2, Mg+2, Na+1, Pb, Cd, and Cu in soil suggests that leachate percolation is having a major impact on the soil. [ABSTRACT FROM AUTHOR]

Nickel‐based superalloys are unique materials with complex doping that demonstrate excellent resistance to mechanical and chemical degradation. Over a long period of use in industry, a variety of information has been accumulated about their possible chemical compounds and features corresponding to a certain composition. One of the main service properties of the alloy is the tensile strength (σ). For a more convenient comparison of the characteristics of the alloys with different chemical compositions, the temperature and holding time of the metal during testing are often combined into a complex Larson–Miller parameter (PLM). The availability of experimental or simulated data on the alloys' properties in the entire range of temperatures and exposures would significantly expand the possibilities of the alloy applications and would allow a more accurate evaluation and comparison of the alloys. In this work, we use a machine learning method for modeling the properties of the alloys according to their composition. A Bayesian regularized artificial neural network was engaged to simulate missing tensile strength values for 278 superalloys. Special data preprocessing and the use of an ensemble of networks during training reduced the model error. Comparison of the predicted and experimental data showed excellent convergence. The method made it possible to obtain enough data to approximate the relation σPLM with a sigmoid function. The slope coefficient is considered as a quantitative expression of the thermal stability of the superalloys. [ABSTRACT FROM AUTHOR]

In this study, two surfactants with the same long chain were synthesized. One shows dicationic and the other tricationic properties. Various spectroscopic methods such as FT-IR, 1H NMR and 13C NMR were used to confirm the structures of the synthesized surfactants. The inhibition activities of two synthesized surfactants against mild steel corrosion in 1.0 M HCl solution were determined using the weight loss method. The 24-h corrosion tests on metal coupons immersed in acidic solutions were carried out using different inhibitor concentrations and similar and successful inhibition was obtained for both surfactants. Current density was determined by potentiodynamic polarization at a single inhibitor concentration to compare with the inhibition efficiency results obtained by decrease in weight method. Based on the current density, the inhibition efficiencies of the surfactants were calculated by Tafel extrapolation method. The inhibition efficiency results obtained by both weight loss and Tafel method were close and consistent. According to both methods, the corrosion inhibition of dicationic surfactant was slightly better than that of tricationic surfactant. By determining the critical micelle concentration for the two surfactants, some physicochemical parameters such as surface tensions and free energy of micelle formation at this concentration were calculated and correlated with their corrosion inhibitory activity. Scanning electron microscopy was used to ascertain the surface roughness conditions of metals submerged in an acidic solution, thus visually proving that surfactants protect the metal surface from corrosion. [ABSTRACT FROM AUTHOR]

A combination of different eco-friendly materials prepared promising fluorescent quantum dots (QDs) through the one-step process using the microwave heating of urea with cellulose, chitosan, and biochar. Characterizations of the prepared QDs, including the investigation of their structure by infrared spectroscopy, Raman analysis, X-ray diffraction, thermal gravimetric analysis, morphology, and optical properties, were performed. The results showed that QDs possess a small size, high UV absorption, and excitation wavelength-dependent fluorescence. The prepared QDs were also tested for metal ions removal from aqueous solutions. The adsorption at different contact times was investigated to optimize the adsorption efficiency of the prepared QDs. All QDs were found to be an ideal sorbent for Cr(II), Cu(II), Mn(II), and Pb(II). From the data, Cr(II) was more highly adsorbed than other metal ions. The results of the kinetic investigation showed that the pseudo-second-order kinetic model fit the adsorption process effectively. In addition, the fluorescence spectra of QDs were changed after the adsorption of metal ions; hence, the prepared QDs could be utilized in environmental sectors such as wastewater pollution detection, adsorption, and chemical sensing applications. [ABSTRACT FROM AUTHOR]

Mercury has been described as been in daily household items such as soaps, skin-lightening creams (SLC), and topical disinfectants. Mercury exposure can reportedly cause damage to the optic nerve and retina. A 30-year-old Somali woman presented with decreased vision and was found to have bilateral optic atrophy. Neuroimaging and laboratory work-up for nutritional deficiencies, heavy metals, and syphilis were performed. Evaluation revealed normal neuroimaging and laboratory work-up except for elevated serum and urine mercury levels. Mercury levels at the initial blood test was 11.1 ug/L (normal limits < 10.0 ug/L) and was 15.7 ug/L on repeat testing. A 24-h urine test showed elevated mercury at 16 ug/24 h (normal limits < 2 ug/24 h). Evaluation of an unlabelled SLC that she was using showed the presence of mercury. It is worth testing for heavy metals in the work-up of bilateral optic atrophy. Clinicians should consider cosmetic products as a potential source of mercury exposure and recommend discontinuation if mercury is present. [ABSTRACT FROM AUTHOR]

Food is one of the most prevalent ways that humans are exposed to metals. Heavy metals including cadmium, iron, zinc, lead, and mercury are harmful to humans and have a detrimental impact on health because they accumulate in biological organs. The concentration levels of these heavy metals were tested in different edible parts of the country (locally raised) chicken from various districts in Karnataka, India, namely Bengaluru, Tumakuru, Mangaluru, and Udupi, using an Atomic-Absorption Spectrophotometer (AAS). Heavy metal concentrations in various chicken parts were found to be below detectable limits (BDL)-0.0062, 0.027-3.178, and 0.262-2.103 ppm for Cd, Fe, and Zn, respectively, whereas Hg and Pb were BDL. The content of Zn was found to be significantly higher in all chicken samples from all examined districts, followed by Fe and Cd. Hg and Pb concentrations, on the other hand, were below the detection level in all samples. The estimated daily intakes (EDIs) of the observed metals from country chicken consumption were found to be lower than their respective FAO/WHO reference oral doses (RfD). The noncarcinogenic health hazards posed by the tested metals to the target population were estimated using the Hazard Quotient (HQ) and Hazard Index (HI) values. The HQ and HI values observed in this estimation were less than one, indicating that exposure to these heavy metals through the consumption of country chicken is unlikely to provide possible health concerns to the examined region's human population. [ABSTRACT FROM AUTHOR]

This study proposed to evaluate high-temperature tensile behavior of micro-scaled metal foils using rectangular samples by a resistance heating (RH)-assisted system incorporating digital image correlation (DIC) with laser speckles. High-temperature tensile tests were conducted for AZ31 magnesium alloys with a thickness of 0.05 and 2 mm in gauge width. To figure out the dominating factor that influences the temperature distribution of the foil with a micro-scale, the temperature of the samples for different materials with and without jig was simulated by finite element analysis and compared with the experimental results. As results, the heat conduction from the sample to the jig is the dominating factor that affects the temperature distribution of the micro-scaled foils rather than the thermal conductivity of the material. Furthermore, the measured temperature distribution and nominal stress–strain curves of rectangular samples show the same profiles with dog-bone samples. It turns out that the strain of micro-scaled metal foils can be measured accurately by the DIC system, in which the deviation of strains is less than 5% for the rectangular sample at the nominal strain larger than 0.05. In particular, the measurement of full strain field for the micro-scaled foils has been achieved. The anisotropy of the foils has been successfully evaluated. It is confirmed that rectangle is a suitable sample shape that can replace the conventional dog-bone shape in the tensile testing for micro-scaled foils by using RH method. The general applicability of the testing system has been proved. [ABSTRACT FROM AUTHOR]

Predicting changes in the surface roughness caused by friction allows the quality of the product and the suitability of the surface for final treatments of varnishing or painting to be assessed. The results of changes in the surface roughness of DC03 steel sheets after friction testing are presented in this paper. Strip drawing tests with a flat die and forced oil pressure lubrication were carried out. The experiments were conducted under various contact pressures and lubricant pressures, and lubrication was carried out using various oils intended for deep-drawing operations. Multilayer perceptrons (MLPs) were used to find relationships between friction process parameters and other parameters (Sa, Ssk and Sku). The following statistical measures of contact force were used as inputs in MLPs: the average value of contact force, standard deviation, kurtosis and skewness. Many analyses were carried out in order to find the best network. It was found that the lubricant pressure and lubricant viscosity most significantly affected the value of the roughness parameter, Sa, of the sheet metal after the friction process. Increasing the lubricant pressure reduced the average roughness parameter (Sa). In contrast, skewness (Ssk) increased with increasing lubrication pressure. The kurtosis (Sku) of the sheet surface after the friction process was the most affected by the value of contact force and lubricant pressure. [ABSTRACT FROM AUTHOR]

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This document discusses the challenges and solutions in environmental analysis, particularly in relation to sampling, detection, and uncertainty. Environmental measurements are crucial for understanding our changing global environment and regulating human activity. However, there are difficulties in ensuring measurement reliability, especially when dealing with small samples, long-term monitoring, low levels of contaminants, and non-normal distribution of data. The document also highlights the importance of validation procedures, detectability, and reporting measurement uncertainty and conformity. The author provides examples and references to guide environmental analysis practices. [Extracted from the article]

This Letter presents oriented growth and switching of thin (∼30 nm) co-sputtered ferroelectric (FE) aluminum scandium nitride (AlScN) films directly on degenerately doped 4H silicon carbide (SiC) wafers. We fabricate and test metal ferroelectric semiconductor capacitors, comprising of Al/Al0.68Sc0.32N/4H-SiC. Our devices exhibit asymmetric coercive electric field values of −5.55/+12.05 MV cm−1 at 100 kHz for FE switching, accounting for the voltage divided by the depletion region of the semiconducting SiC substrate under positive voltages. Furthermore, the FE AlScN exhibits a remanent polarization of 110 ± 2.8 μC cm−2, measured via a voltage-pulsed positive-up negative-down measurement. We further investigate the reliability of the reported devices, revealing an endurance of ∼3700 cycles and a retention time of 9.5 × 105 s without any significant loss of polarization. Our findings demonstrate the bipolar switching of high-quality thin Al0.68Sc0.32N films on doped SiC substrates enabling monolithic integration of nonvolatile memory with SiC-based logic devices appropriate for high temperature operation as well as for high-power switching, memory, and sensing applications. [ABSTRACT FROM AUTHOR]

Two rhodamine‐anthracene derivative probes (RA1 and RA2) were designed and synthesized to incorporate different lengths of diamine chains between the rhodamine and anthracene moieties. Among the 16 different metal ions tested, RA1 exhibited the highest fluorescence enhancement in response to Hg2+ with a limit of detection (LOD) of 3.76×10−7 M, while RA2 showed the greatest fluorescence enhancement in the presence of Fe3+ with the LOD of 2.41×10−7 M. Notably, RA1 effectively eliminated the interference caused by Fe3+ during Hg2+ detection, whereas RA2 successfully eliminated the interference of Hg2+ during Fe3+ determination. This response difference between the two ions holds particular importance in scenarios where both heavy metal ions coexist. Additionally, fluorescence microscopy imaging of mouse mammary cancer cells (4T1) under the influence of Fe3+ demonstrated the potential applications of the probe. This study highlights the significance of a simple molecular design approach in tailoring probe selectivity by modifying the intramolecular flexible chain length. [ABSTRACT FROM AUTHOR]

This paper addresses the challenge ol accurately measuring the conductivity ol highly conductive thin metal loils using existing testing methods. To this end, we analyzed the ellect of metal loil thickness on electric lield reflection At the interlace between ultra-thin metal loils and air, and the distribution ol internal electric lield and surface impedance ol these loils, as well as the coil impedance in eddy current testing systems. Subsequently, we proposed a new non-destructive testing method lor measuring the conductivity ol metal foils thinner than 100 which relies on using two loils of different thicknesses to eliminate the disruptive effects of electric lield rellection at the interlace. The results demonstrate that this new method produces testing deviations of only about 3% in silver, copper, and copper-chromium-zirconium loils, which is signilicantly lower than the error rate ol the commonly used, improved stacked loil method(about 20%). Moreover, employing an appropriate thickness design further reduces the testing deviation to 2%. The new method has a conductivity testing range of 80% 110% IACS. This study is expected to contribute to the improvement ol standardized high-conductivity ultra-thin metal loil testing protocols, which are vital in scientific research and industrial applications. [ABSTRACT FROM AUTHOR]

Friction Stir Welding (FSW) is a recent joining technique that has received considerable attention. FSW causes significant variations in the material microstructure commonly associated with changes in the mechanical properties. The present study deals with the creep response of pure titanium (CP-Ti grade 2) after FSW. Dog-bone creep samples, obtained by machining, which show the longitudinal axis of each sample being perpendicular to the welding direction, were tested in constant load machines at 550 and 600 °C. The creep response of the FSW samples was analyzed and compared with that of the unwelded material. The shape of the creep curves was conventional, although the FSW samples went to rupture for strains lower than the base metal. The minimum creep rates for FSW samples were, in general, lower than for the unwelded metal tested in equivalent conditions. In addition, when the applied stress was high, deformation concentrated in the parent metal. The creep strain became more and more homogeneous along the gauge length as testing stress decreased. A constitutive model, recently developed for describing the creep response of the base metal, was then used to rationalize the observed reduction in the minimum strain rate in FSW samples. [ABSTRACT FROM AUTHOR]

Evidence from cyclic tests on metals, elastomers, and sandy soils reveals that damping forces are nearly rate-independent and structural (hysteretic or rate-independent) damping was widely adopted since the 1940s. While there is no time-domain constitutive equation for a linear spring connected in parallel with a rate-independent dashpot, the dynamic stiffness (transfer function) of this mechanical network can be constructed in the frequency domain; and it was known since the early 1960s that this mechanical network exhibits a non-causal response. In view of its simplicity in association with the wide practical need to model rate-independent dissipation, this mechanical network was also implemented in time-domain formulations with the label complex stiffness where the force output, P(t) is related in the time domain to the displacement input, u(t), with P(t) = k(1 + iη)u(t). This paper shows that the complex stiffness, as expressed in the time domain by various scholars, is a fundamentally flawed construct since in addition to causality it violates equilibrium. [ABSTRACT FROM AUTHOR]

Introduction Nuss procedure is the main reason for metal implants use by pediatric and thoracic surgeons. There is an ongoing debate on how to avoid allergic complications. Herein we describe our 8-year experience with systematic preoperative metal patch testing and our selective titanium bar use in Nuss procedure. Materials and Methods This is a single center retrospective observational cohort study of patients who underwent the Nuss procedure from 2013 to 2020. Preoperative metal patch testing was done in all cases. Criteria for titanium bar utilization were: a positive test for a major component of the stainless-steel bar; or a positive metal patch test and a positive history of atopy, food or metal allergy, or previous allergic reaction to an implant or device. Results In total, 56 patients were included. Most were male (91.1%) with a median age of 15.0 (13.0–22.0) years old. 19.6% had a positive preoperative metal patch test and 54.5% of these had no personal history of atopy. Stainless-steel bars were used in 27.3% of those patients and titanium bars were used in 72.7%. One patient had a documented minor allergy reaction. None of the 56 patients required early bar removal. Conclusion Our study suggests that routine preoperative allergy testing and a judicious use of titanium bar are safe and avoid metal allergic complications. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the heavy metals concentrations in soil, inflorescences of Brassica napus L. and rapeseed honey sampled from some regions of north-eastern Bulgaria. Thirteen locations were selected for experimental studies. The soils, plants and honey samples were taken from conventional beekeeping areas away from major industrial pollutants. The median amounts of elements in the soil samples (mg/kg dry weight (DW)) are 1.1246 for Fe(s), 0.7048 for Al(s), 0.5636 for Pb(s), 0.1658 for Cu(s) and 0.0148 for Zn(s). The median amounts of heavy metals measured in the inflorescences of Brassica napus (mg/kg DW) are 5.5430 for Fe(p), 2.9095 for Zn(p), 1.3225 for Pb(p), 0.2593 for Cu(p) and 0.2105 for Al(p). The median heavy metals concentrations in tested honey (mg/kg DW) are 1.0026 for Fe(h), 0.1849 for Al(h), 0.1832 for Pb(h), 0.1250 for Zn(h), and 0.0702 for Cu(h). The relationship between the heavy metal in soil, plants and honey was investigated using Spearman's rank correlation coefficient. Significant differences in the concentrations of Fe(s), Al(s) and Pb(s) in soils, Fe(p) and Zn(p) in the plant samples and Fe(h) in honey samples from the different locations were found. The heavy metal content tested in honey did not pose a risk to human health. [ABSTRACT FROM AUTHOR]

Purpose: To report our initiatives and treatment results for patients with colorectal cancer with metal allergy. Methods: A total of 27 patients (2.6%) with a history of metal contact dermatitis were identified among 1027 patients who underwent curative resection of colorectal cancer from 2014 to 2020. The results of the patch test, perioperative results, and postoperative colonoscopy findings were also investigated. Results: The patch test for metal allergens and staples was performed in 21 patients (77.8%), and 13 of them (61.9%) tested positive for at least one metal allergen. Ni (38.1%), Co (28.6%), and Pd (19.0%) showed higher positive rates than other metals, and 1 patient (4.8%) tested positive for staples. Stapled anastomosis/suturing was performed as planned in 15 of 27 patients. In 10 patients, the anastomosis method was changed from stapled to hand-sewn according to the no-patch test results (60%), positivity for multiple metals (20%), positivity for staples (10%), and surgeon's judgment (10%). No complications and abnormal colonoscopy findings were found to be associated with stapled anastomosis/suturing. Conclusion: The patch test is useful for selecting an optimal anastomosis method for patients with suspected metal allergy. [ABSTRACT FROM AUTHOR]

Additive manufacturing processes play a disruptive role in several industrial sectors. Among them, wire arc additive manufacturing (WAAM) is a very promising process for the production of large-scale steel components and structures. As a common characteristic of innovative technologies, this process requires additional research and experimental work in order to understand how its thermal cycles will modify the mechanical and metallurgical properties of the manufactured components. Considering the lack of literature on the properties of WAAM components from specific steel alloys, the present work proposes a benchmark evaluation of five different steel filler metals based on their mechanical properties and operational parameters when applied for additive manufacturing. The mechanical properties, such as the tensile strength, yield strength, elongation, Charpy impact toughness, and hardness, were evaluated together with operational parameters such as cost, printability, spatter, and fume formation during manufacturing, defect-free printing, and heat input. These were analyzed in order to obtain a full evaluation and comparison of the five filler metals. The experimentally determined results of every above-mentioned aspect were higher or similar to the values found in the literature for generic steel filler metals used in additive manufacturing. This means that a designer or welding engineer can select the WAAM steel filler metal for further testing based on the welding wire datasheet. Besides that, a comparison was performed between blocks manufactured by WAAM with some frequently used base metals, in plate format, confirming its applicability. [ABSTRACT FROM AUTHOR]