Excess Metal Research Articles

Superalkalis with Hydrogen as Central Electronegative Atom and their Possible Applications: Ab Initio and DFT Study.

Superalkalis are unusual species having ionization energies lower than that of the alkali metals. These species with various applications are of great importance in chemistry due to their low ionization energies and strong reducing property. A typical superalkali contains a central electronegative core decorated with excess metal ligands. In the quest for novel superalkalis, we have designed the superalkalis HLi2, HLiNa and HNa2 using hydrogen as central electronegative atom for the first time employing high level ab initio (CCSD(T), MP2) and density functional theory (ωB97X-D) methods. The superalkalis exhibit very low ionization energies, even lower than that of cesium. Stability of these species is verified from binding energy and dissociation energy values. The superalkalis are capable of reducing SO2, NO, CO2, CO and N2 molecules by forming stable ionic complexes and therefore can be used as catalysts for the reduction or activation of systems possessing very low electron affinities. The superalkalis form stable supersalts with tailored properties when interact with a superhalogen. They also show remarkably high non-linear optical responses, hence could have industrial applications. It is hoped that this work will enrich the superalkali family and spur further theoretical and experimental research in this direction.

Elemental composition and mineralogical characteristics of volcanic ash and soil affected by the eruption of Mount Semeru, East Java

Elemental composition and mineralogical characteristics of volcanic ash and soil affected by the eruption of Mount Semeru, East Java

Predictors of urinary heavy metal concentrations among pregnant women in Jinan, China

BackgroundToxic heavy metal exposure and insufficiency or excess of essential heavy metals may have negative effects on pregnant women’s health and fetal growth. To date, the predictors of pregnant women’s heavy metal exposure levels remain unclear and vary with different regions. The study intended to explore potential predictors of exposure to heavy metals individually and high co-exposure to heavy metal mixtures. MethodsWe recruited 298 pregnant women in first trimester from prenatal clinics in Jinan, Shandong Province, China, and collected spot urine samples and questionnaire data on their demographic characteristics, lifestyle habits, consumption of food and dietary supplement, and residential environment. All urine samples were analyzed for seven heavy metals: cobalt (Co), molybdenum (Mo), strontium (Sr), arsenic (As), cadmium (Cd), lead (Pb) and mercury (Hg). ResultsFactors associated with single heavy metal concentration were as follows: a) urinary As, Sr and Cd increased with women’s age respectively; b) pregnant women with higher monthly household income per capita had lower Sr and Mo levels; c) pregnant women with intermittent folic acid supplementation and those not taking tap water as domestic drinking water had lower Sr concentrations; d) Cd was positively linked with consumption frequency of rice; e) Hg was adversely related to consumption frequency of egg and the women who took purified water as domestic drinking water had lower Hg exposure. In addition, pregnant women’s age was positively associated with odds of high co-exposure to Co, As, Sr, Mo, Cd and Pb; while those with an educational level of college had lower odds of high exposure to such a metal mixture compared with those whose educational levels were lower than high school. ConclusionPredictors of single urinary heavy metal concentration included pregnant women’s age (As, Sr and Cd), monthly household income per capita (Sr and Mo), folic acid supplementation (Sr), rice consumption frequency (Cd), egg consumption frequency (Hg) and the type of domestic drinking water (Sr and Hg). Pregnant women with older age, lower educational level tended to have high co-exposure to Co, As, Sr, Mo, Cd and Pb.

Nitrate modulates the physiological tolerance responses of the halophytic species Sarcocornia fruticosa to copper excess

Coexistence impact of pollutants of different nature on halophytes tolerance to metal excess has not been thoroughly examined, and plant functional responses described so far do not follow a clear pattern. Using the Cu-tolerant halophyte Sarcocornia fruticosa as a model species, we conducted a greenhouse experiment to evaluate the impact of two concentration of copper (0 and 12 mM CuSO4) in combination with three nitrate levels (2, 14 and 50 mM KNO3) on plant growth, photosynthetic apparatus performance and ROS-scavenging enzymes system. The results revealed that S. fruticosa was able to grow adequately even when exposed to high concentrations of copper and nitrate. This response was linked to the plant capacity to uptake and retain a large amount of copper in its roots (up to 1500 mg kg−1 Cu), preventing its transport to aerial parts. This control of translocation was further magnified with nitrate concentration increment. Likewise, although Cu excess impaired S. fruticosa carbon assimilation capacity, the plant was able to downregulate its light-harvesting complexes function, as indicated its lowers ETR values, especially at 12 mM Cu + 50 mM NO3. This downregulation would contribute to avoid excess energy absorption and transformation. In addition, this strategy of avoiding excess energy was accompanied by the upregulation of all ROS-scavenging enzymes, a response that was further enhanced by the increase in nitrate concentration. Therefore, we conclude that the coexistence of nitrate would favor S. fruticosa tolerance to copper excess, and this effect is mediated by the combined activation of several tolerance mechanisms.

Combating heavy metals in wheat grains under drought – is alien or ancient germplasm a solution to secure food and health?

Alien and ancient wheat germplasms have been utilized to combat diseases and improve yield performance under climate change. However, the potential risk of excessive heavy metal uptake with these germplasms has been less studied. In order to ensure food security, this study aimed to evaluate the levels of cadmium (Cd), lead (Pb) and mercury (Hg) in 30 wheat lines, including modern, old and wheat-rye introgression genotypes grown under three conditions i.e., control, early drought and late drought. The results of this study revealed a generally higher Cd grain accumulation in old and 1R genotypes than in the other genotype groups evaluated here, while old genotypes also showed an excess Pb grain concentration. The induced late drought resulted in an increased Cd uptake in wheat, leading to significantly elevated grain Cd concentration in modern, 1R, 1RS and 2R genotypes, while similar results were not obtained for the other heavy metals e.g. Pb or Hg. Specifically, an old genotype, 207, showed an extremely high Cd value across control and drought conditions. There was a greater genotypic variation in Pb concentration compared to Cd, while consistently high Hg concentrations were observed in several genotypes carrying 1R or 1RS. Some wheat-rye introgression genotypes, particularly those with the 3R chromosome, showed a low Cd accumulation across all treatments. The results from the present study pin-point the necessity of a rigorous assessment of heavy metal accumulation in wheat grain when utilizing ancient and alien genetic resources in breeding for disease resistance, and wheat resilience to environmental stress and climate change. Furthermore, the specific lines identified in this study with elevated heavy metal accumulation should be avoided in breeding programs. Additionally, mechanisms for the found differences in heavy metals accumulation among genotypes and treatments should be further revealed.

Response of antioxidant activity, active constituent and rhizosphere microorganisms of Salvia miltiorrhiza to combined application of microbial inoculant, microalgae and biochar under Cu stress

Salvia miltiorrhiza, a widely used medicinal herb renowned for its properties in promoting blood circulation, removing blood stasis and alleviating pain, is currently facing quality degradation due to excessive heavy metal levels, posing a threat to medication safety. In order to investigate the effects of microbial inoculant, microalgae and biochar on the growth of Salvia miltiorrhiza under copper (Cu) stress, as well as its Cu absorption, antioxidant activity, active component contents and rhizosphere microbial community, a pot experiment was conducted. Salvia miltiorrhiza plants were cultivated in the soil containing 400 mg/kg of Cu for six months and treated with microbial inoculant, microalgae and biochar, either individually or in combination. Almost all soil amendment treatments led to an increase in root biomass. Notably, co-application of microbial inoculant and microalgae had the optimal effect with a 63.07 % increase compared to the group treated solely with Cu. Moreover, when microbial inoculant was applied alone or in combination with microalgae, the Cu content in plant roots was reduced by 19.29 % and 25.37 %, respectively, whereas other treatments failed to show a decreasing trend. Intriguingly, Cu stress increased the active component contents in plant roots, and they could also be enhanced beyond non-stress levels when microbial inoculant and microalgae were applied together or in combination with biochar. Analyses of plant antioxidant activity, soil properties and rhizosphere microorganisms indicated that these amendments may alleviate Cu stress by enhancing peroxidase activity, facilitating plant nutrient absorption, and enriching beneficial microorganisms capable of promoting plant growth and mitigating heavy metal-induced damage. This study suggests that the combined application of microbial inoculant and microalgae can reduce Cu levels in Salvia miltiorrhiza while enhancing its quality under Cu stress.

Influence of magnetic field upon electrode kinetics and ionic transport

Performance properties in lithium-ion, sodium-ion, and zero excess metal batteries are currently limited by the sluggish ion diffusion and inhomogeneity of the transport ion flux, resulting in poor formation, low rates, and short cycle lives. In this work, a magnetic field is applied to the cell by the incorporation of a NdFeB magnetic spacer, and the effect upon the kinetics and transport properties at each electrode is studied using galvanic charge and discharge, electrochemical impedance spectroscopy, and intermittent titration techniques. Stabilization of the anode-free or zero excess sodium and lithium metal cells is achieved during formation, and upon cycling. Reduced cell overpotential is observed with resulting higher areal capacities, with improved ionic diffusion through the electrode. Upon cycling metallic dendritic structures are suppressed due to the inhomogeneity of ion flux, and the likely competing kinetics of plating at a metallic tip and the surrounding surface. At the NMC electrode, improved kinetics are observed with lower charge-transfer resistance (Rct) due to the reshaped and aligned domain in the ferromagnetic Ni of NMC cathode. Pulsed current methods further confirm enhanced cationic diffusion in the anode graphite materials, particularly at high mass loading of 4 mA h cm−2 and high C rates. Consequently, the combination of enhanced reaction kinetics on the ferromagnetic cathode and improved diffusion kinetics in the porous anode leads to excellent full-cell performance compared to control groups. This study highlights the potential of magnetic fields in enhancing diffusion and reaction kinetics for rechargeable batteries (Li, Na, K, Mg, etc.), and may provide routes for extending cycle life, reconditioning cells, and improving formation protocols.

Three anionic surfactants for corrosion inhibition in cobalt CMP: Research on validity and mechanism

Inhibitors are introduced into the slurry to avoid excessive metal corrosion during the chemical mechanical polishing (CMP) process. The anti-corrosion effect of surfactants in CMP was not investigated systematically in past studies. In this paper, three eco-friendly anionic surfactants, potassium laurate, potassium oleate, and dodecyl benzenesulfonic acid, were studied in depth as cobalt CMP inhibitors. Electrochemical experiments demonstrated that the three inhibitors act as anodic inhibitors. Static etching tests and surface morphology analysis proved that they can effectively inhibit the corrosion rate of cobalt and improve surface morphology. XPS results demonstrated that the inhibitor reduces corrosion by inhibiting cobalt oxidation. DFT calculations demonstrated that inhibitors adsorb on the cobalt surface through the O atoms in hydrophilic groups, while the CC double bond and benzene ring can significantly enhance the adsorption. Molecular dynamics simulations showed that the inhibitors are adsorbed on the cobalt surface in parallel. Additionally, all three surfactants improved the solution's wettability on cobalt. This report provides critical insights into the corrosion inhibition specific to cobalt CMP and offers an approach to realize the multi-functionality of a single agent in slurries.

Research Progress on in-situ Remediation of Typical Heavy Metals in Petroleum Hydrocarbon-contaminated Soil Enrichment by Plants

Petroleum hydrocarbon is one of the dangerous substances in the process of petroleum development, refining, processing, transportation, and production. In the related activities of the petroleum industry, the output is large, and improper treatment will cause pollution to the surrounding environment. It is an urgent problem to conduct harmless and resource treatment of petroleum hydrocarbon polluted soil. Plant enrichment, as an environmentally friendly and pollution-free technical means, has the advantages of low cost and small change to the soil environment and effectively solves the problems of excessive heavy metals in petroleum hydrocarbons through plant enrichment. In this paper, the development process of plant enrichment, remediation methods, and plant enrichment of typical heavy metals (Cd, Hg, Zn) in petroleum hydrocarbon-polluted soil were systematically introduced. Through investigation, the mechanism and influencing factors of plant enrichment of heavy metals in the presence of petroleum hydrocarbons were summarized and analyzed, and the possible development direction of plant enrichment technology in the future was prospected.

Construction of Selective Ion Transport Polymer at Anode-Electrolyte Interface for Stable Aqueous Zinc-Ion Batteries.

Rampant dendrite formation and serious adverse parasitic reactions induced by migration of dissolved V/Mn cathode ions on Zn anode have hampered the high performance of aqueous zinc-ion batteries (AZIBs). Inspired by the coordination chemistry between functional groups of polymer and electrolyte ions, a freestanding layer consisting of dopamine-functionalized polypyrrole (DA-PPy) nanowires served as a selective ion transport layer at the anode-electrolyte interface to address these two issues, which could simultaneously avoid polarization caused by the introduction of an additional interface. On the one hand, the DA-PPy layer displays excellent zinc ion and charge transfer ability, as well as provides chemical homochanneling for zinc ions at the interface, which endow the DA-PPy layer with properties as a chemical guider and physical barrier for dendrite inhibition. On the other hand, the DA-PPy layer can trap excess transition metal ions fleeing from the cathodes, thus serving as a chemical barrier, preventing the formation of Vx+/Mnx+-passivation on the surface of the zinc anode. Consequently, the AZIBs based on V2O5 and MnO2 cathodes involving the DA-PPy functional layer show a great improvement in the capacity retention.

Enhanced ammonia removal in tidal flow constructed wetland by incorporating steel slag: Performance, microbial community, and heavy metal release

Utilizing alkaline solid wastes, such as steel slag, as substrates in tidal flow constructed wetlands (TFCWs) can effectively neutralize the acidity generated by nitrification. However, the impacts of steel slag on microbial communities and the potential risk of heavy metal release remain poorly understood. To address these knowledge gaps, this study compared the performance and microbial community structure of TFCWs filled with a mixture of steel slag and zeolite (TFCW-S) to those filled with zeolite alone (TFCW-Z). TFCW-S exhibited a much higher NH4+-N removal efficiency (98.35 %) than TFCW-Z (55.26 %). Additionally, TFCW-S also achieved better TN and TP removal. The steel slag addition helped maintain the TFCW-S effluent pH at around 7.5, while the TFCW-Z effluent pH varied from 3.74 to 6.25. The nitrification and denitrification intensities in TFCW-S substrates were significantly higher than those in TFCW-Z, consistent with the observed removal performance. Moreover, steel slag did not cause excessive heavy metal release, as the effluent concentrations were below the standard limits. Microbial community analysis revealed that ammonia-oxidizing bacteria, ammonia-oxidizing archaea, and complete ammonia-oxidizing bacteria coexisted in both TFCWs, albeit with different compositions. Furthermore, the enrichment of heterotrophic nitrification-aerobic denitrification bacteria in TFCW-S likely contributed to the high NH4+-N removal. In summary, these findings demonstrate that the combined use of steel slag and zeolite in TFCWs creates favorable pH conditions for ammonia-oxidizing microorganisms, leading to efficient ammonia removal in an environmentally friendly manner.

Enhanced detection of copper residues on citrus surfaces: An innovative copper fenton-catalysed colorimetric approach using creatinine and molybdenum trioxide

Accurate quantification of residual copper from inorganic copper reagents on the surface of citrus fruits is crucial for preventing diseases caused by excessive heavy metal intake. In this study, we developed a rapid colorimetric strategy for copper detection that is enhanced under near-neutral pH conditions, using molybdenum trioxide (MoO3) and creatinine for copper-Fenton catalysis. The introduction of MoO3 enriches the redox reactions of Cu2+/Cu+ within the complex formed by copper ions and creatinine, leading to enhanced copper-Fenton catalytic activity at near-neutral pH. In the presence of H2O2, this system oxidises colourless 3,3′,5,5′-tetramethylbenzidine (TMB) to blue oxTMB, thereby affording a sensitive colorimetric detection platform for Cu2+. The designed method offers high sensitivity for Cu2+ detection, with a linear range of 0.011.0 μg/mL and a detection limit as low as 0.007 μg/mL. This method was effectively used to analyse copper reagent residues on citrus surfaces, achieving recovery rates of 92.0%115.0%. With its high sensitivity, selectivity, simplicity, and low cost, this colorimetric method shows great potential as an effective approach for determining copper ion levels, particularly for monitoring copper residues in agricultural products.

Appraisal of pollution levels and non-carcinogenic health risks associated with the emergence of heavy metals in Indonesian community water for sanitation, hygiene, and consumption

Excessive heavy metal concentrations in water can pose a threat to human health. The research analyzed 160 groundwater samples used for hygiene and sanitation, of which 62 were used for consumption, and 98 other types of drinking water were analyzed. The research findings indicate that 6% of groundwater for hygiene and sanitation and 13% of drinking water (7.8% groundwater, 5.2% refill water) were deemed unfit for use due to elevated concentrations of certain heavy metals surpassing the maximum limits. As, Cd, Co, Hg, Mn, and Pb were detected in several drinking water samples deemed unsuitable for consumption. Several heavy metals suspected to originate from natural sources are Co, Fe, Mn, As, and Zn, while Pb, Cd, Hg, and Co are suspected to have anthropogenic sources. Only arsenic exposure through the ingestion pathway posed a non-carcinogenic health risk to the local population. Children were found to be more susceptible than adult males and females. The estimated average non-carcinogenic risk levels based on the water sources were refill water > well water > rainwater > spring water. Therefore, it is essential to monitor raw water sources at refill water depots in the study area and implement policies related to the quality of raw water sources, technology maintenance processes, and the quality of processed water from refill water depots. Additionally, the community should be educated about household-scale water treatment to minimize health risks and consider using untreated well water and rainwater for consumption.

Effect of oxygen vacancy of lignite-char-supported Co catalysts doped with In on efficient dry reforming of methane

In this study, a series of catalysts rich in oxygen vacancies were prepared through the introduction of indium (In) for application in the dry reforming of methane. Among these catalysts, one doped with 2 wt% In, named as Co-2In/C, showcases a higher surface area (417 m2/g) and smaller particle size (4.21 nm). The stability assessment for Co-2In/C catalysts conducted under conditions of 800 °C, 0.5 MPa and a flow rate of 30,000 mL·h−1·g-1cat over 100 h resulted in CH4 and CO2 conversions of 73 % and 83 %, respectively, and a ratio of H2/CO is 0.65 without evident deactivation. The generation of more oxygen vacancies balances the redox capability of the catalyst and prevents excessive metal agglomeration. Moreover, an increase in oxygen vacancy concentration accelerates carbon elimination and extends the catalyst life.

Application and Parameter Optimization of Electro-Kinetic Geosynthetics Electrodes Based on the Wild Horse Optimizer in Horizontal Electric Field Sludge Dewatering

This study systematically compared the performance of five corrosion-resistant electrode materials for electro-dewatering. Through a comprehensive analysis of dewatering efficiency, energy consumption, and corrosion resistance, conductive plastic composite electrodes (EKG) were selected as the optimal electrode material for experimentation. Additionally, the impact of electric field strength and electrode spacing on the efficiency and energy consumption of electro-dewatering (EDW) was investigated. The results showed that the increase in electric field intensity could improve the solid content and dewatering efficiency of the sediments, but the corresponding energy consumption also increased. The increased spacing of the plates reduced the dehydration effect and increased the energy consumption. By employing the Wild Horse Optimization algorithm, empirical and multifactorial response models for the dewatering solidification process were established, aimed at predicting the dewatering performance and energy consumption. The study concludes that for the remediation of heavy metals, the electric field strength should not exceed 10 V/cm to avoid excessive heavy metal migration and potential adverse chemical reactions.

Effect of hesperidin on growth, photosynthesis, antioxidant systems and uptake of cadmium, copper, chromium and zinc by Celosia argentea plants

Rapid industrialization and extensive agricultural practices are the major causes of soil heavy metal contamination, which needs urgent attention to safeguard the soils from contamination. However, the phytotoxic effects of excessive metals in plants are the primary obstacle to efficient phytoextraction. The present study evaluated the effects of hesperidin (HSP) on metals (Cu, Cd, Cr, Zn) phytoextraction by hyperaccumulator (Celosia argentea L.) plants. For this purpose, HSP, a flavonoid compound with strong antioxidant potential to assist metal phytoextraction was used under metal stress in plants. Celosia argentea plants suffered significant (P ≤ 0.001) oxidative damage due to the colossal accumulation of metals (Cu, Cd, Cr, Zn). However, HSP supplementation notably (P ≤ 0.001) abated ROS generation (O2•‒, •OH, H2O2), lipoxygenase activity, methylglyoxal production, and relative membrane permeability that clearly indicated HSP-mediated decline in oxidative injury in plants. Exogenous HSP improved (P ≤ 0.001) the production of non-protein thiol, phytochelatins, osmolytes, and antioxidant compounds. Further, HSP enhanced (P ≤ 0.001) H2S and NO endogenous production, which might have improved the GSH: GSSG ratio. Consequently, HSP-treated C. argentea plants had higher biomass alongside elevated metal accumulation mirrored as profound modifications in translocation factor (TF), bioaccumulation coefficient (BAC), and bioconcentration factor (BCF). In this context, HSP significantly enhanced TF of Cr (P ≤ 0.001), Cd (P ≤ 0.001), and Zn (P ≤ 0.01), while BAC of Cr (P ≤ 0.001), Cd (P ≤ 0.001), and Zn (P ≤ 0.001). Further, BCF was significant (P ≤ 0.05) only in plants grown under Cr-spiked soil. Overall, HSP has the potential for phytoremediation of metals by C. argentea, which might be a suitable strategy for metal-polluted soils.

Thermal gradient strategy to improve seeding for high rate zero excess lithium metal batteries

Zero excess lithium metal batteries (LMBs) have traditionally suffered from short cycle life due to nonuniform processes that result in parasitic side reactions and a subsequent loss of lithium inventory and electrolyte. The experiments herein demonstrate that zero excess LMB cells cycled with a low thermal average and thermal gradient outperform cells cycled under isothermal conditions during early cycles. Specifically, a low thermal average of ∼6.4°C and thermal gradient of <1°C across the cell is shown to increase the overpotential for lithium deposition at the anode current collector, likely resulting in smaller and higher density nucleates, providing film like morphologies observed with microscopy. Improved performance from this approach is demonstrated at high cycling rates (>4C) and mismatched charge/discharge rates. Optimal cycling behavior was observed with 2C charging (30 min) and 3C discharging (20 min). These advantages were translated to the system relevant form factor-pouch cell (20X capacity). Based on the performance enhancement observed with extended application of a thermal gradient, we demonstrate the use of the environment as a formation strategy, to perpetuate improved plating in stripping over the cycle life of zero excess LMBs operating in ambient conditions.

Drip irrigation reduces the toxicity of heavy metals to soybean: By moving heavy metals out of the root zone and improving physiological metabolism

Excessive heavy metal content in soil can seriously hinder plant physiological metabolism and growth. This study, with soybean, examined how drip irrigation reduced heavy metal toxicity. The drip irrigation experiments with four irrigation frequencies were conducted by controlling the lower limit of the soil matric potential (D1: −10 kPa; D2: −20 kPa; D3: −30 kPa; D4: −40 kPa). Through comparison with traditional surface irrigation, the effects of drip irrigation on heavy metal distribution, soybean growth status, physiological metabolism and transcriptome under Cd, Pb and Cr(VI) composite pollution were comprehensively analyzed. The results show that (i) The Cd, Pb and Cr(IV) in soil migrated away from the plant under drip irrigation, thereby reducing the inhibition of heavy metal stress on soybean growth at the root, among which D1 had the best improvement effect on soybean growth. (ii) Drip irrigation improved the resistance of soybean to heavy metal stress, and promoted the transport and fixation of free Cd2+, Pb2+ and Cr6+ in cells, thereby reducing the damage of oxidative stress and heavy metal ions to cell structure. (iii) Drip irrigation was conducive to the energy supply and protein stability of cell physiological metabolism, which helped the improvement of soybean physiological activity. Overall, compared with surface irrigation, drip irrigation reduced the toxicity of heavy metals to soybeans by moving heavy metals out of the root zone and enhancing physiological activity. The results of this study can provide a theoretical basis for the application of drip irrigation technology in the prevention and control of heavy metal pollution, and provide a new strategy for the safe production of agriculture.

A real time study of the coupled electrochemical and mechanical behaviors of the spinel cathodes in LIBs.

Spinel cathode materials have great application prospects in lithium batteries (LIBs) due to their characteristics of abundant raw materials, simple preparation processes, and cobalt-free nature. During the electrochemical cycles, the specific capacity of the electrodes decreases significantly due to the dissolution of excess metal ions and mechanical degradation, which hinder their further application and development. Here, a bending curvature measurement system (BCMS) was designed to simultaneously measure the mechanical properties of the spinel cathodes during the electrochemical reaction. Three types of cathodes were chosen as the working cathode, and the coupled mechanical and electrochemical properties were analyzed to understand their degradation mechanism. During cycling, a hysteresis loop is observed for the curvature, modulus, plain strain, and stress, where LiMn2O4 (LMO) has the largest loop for the mechanical response while the LiNi0.5Mn1.5O4@Al2O3 (LNMO@Al) one has the smallest loop. Besides, the changing trend of LNMO@Al is the smallest in multiple cycles and it shows the more stable mechanical properties. This study shows from in situ mechanical measurements that the mechanical properties can greatly affect the electrochemical performance of the cathodes. These findings could offer new insights into the understanding of the electrochemical performance degradation in the spinel cathodes and can help develop strategies to enhance the performance of LIBs.

Pengukuran Kualitas Air Limbah Sawit Berdasarkan Baku Mutu Air Limbah Menggunakan AAS

Palm oil industry waste is waste generated from the palm oil processing process. Palm oil liquid waste generally contains heavy metals, one of which is Cu and Zn. The presence of excessive Cu and Zn heavy metals can have a negative impact on living things and the surrounding environment. In this journal, the determination of the heavy metal content of Cu and Zn in palm oil wastewater was carried out using the AAS method with acetylene gas at a wavelength of 324.8 nm to determine the content of Cu metal content and at a wavelength of 213.9 nm to determine the Zn metal content. The results of determining the content of heavy metals Cu and Zn in sempel 1, 2 and 3 contained in palm oil wastewater which are still below the maximum limit of the quality standards obtained, namely less than 2 ppm for Cu metal and less than 5 ppm for Zn metal. utilized by living things and the surrounding environment.