Zinc Salts Research Articles

Insights Into the Role of Copper in Neurodegenerative Diseases and the Therapeutic Potential of Natural Compounds.

Neurodegenerative diseases encompass a collection of neurological disorders originating from the progressive degeneration of neurons, resulting in the dysfunction of neurons. Unfortunately, effective therapeutic interventions for these diseases are presently lacking. Copper (Cu), a crucial trace element within the human body, assumes a pivotal role in various biological metabolic processes, including energy metabolism, antioxidant defense, and neurotransmission. These processes are vital for the sustenance, growth, and development of organisms. Mounting evidence suggests that disrupted copper homeostasis contributes to numerous age-related neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), amyotrophic lateral sclerosis (ALS), Wilson's disease (WD), Menkes disease (MD), prion diseases, and multiple sclerosis (MS). This comprehensive review investigates the connection between the imbalance of copper homeostasis and neurodegenerative diseases, summarizing pertinent drugs and therapies that ameliorate neuropathological changes, motor deficits, and cognitive impairments in these conditions through the modulation of copper metabolism. These interventions include Metal-Protein Attenuating Compounds (MPACs), copper chelators, copper supplements, and zinc salts. Moreover, this review highlights the potential of active compounds derived from natural plant medicines to enhance neurodegenerative disease outcomes by regulating copper homeostasis. Among these compounds, polyphenols are particularly abundant. Consequently, this review holds significant implications for the future development of innovative drugs targeting the treatment of neurodegenerative diseases.

Tough Self-Healing Materials via In Situ Growth of Zeolitic Imidazolate Framework-8 Nanocrystals in Polymers.

Construction of self-healing materials with improved mechanical performanceis a great challenge. A strong and tough self-healing composite is fabricated via in situ growth of zeolitic imidazole framework-8 (ZIF-8) nanocrystals in imidazole-containing polymer networks. By adjusting the stoichiometric ratio of the zinc salt to 2-methylimidazole, composites with various mechanical performances are obtained. The existence of ZIF-8 nanocrystals via in situ growth in the polymer networks is confirmed by X-ray diffraction (XRD), transmission electron microscopy (TEM), and atomic force microscopy (AFM). The zinc-imidazole interactions between the ZIF-8 nanocrystals and the polymer are confirmed by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. The composites can repair themselves under mild conditions owing to dynamic zinc-imidazole interactions. The self-healing efficiency of composites can reach up to 91% under the condition of 60°C for 48h. In contrast to the pure zinc cation crosslinking system, the composite containing ZIF-8 nanocrystals prepared via in situ growth exhibited enhanced tensile strength and toughness by 43% and 100%, respectively. This study proves that incorporating the metal-organic frameworks(MOFs) materials into a self-healing system via an in situ growth strategy is highly promising for designing self-healing materials with improved mechanical performance.

Influence of enzyme drug and adsorbent on digestive metabolism processes of steers fattening in technogenic zone

In the practice of feeding of young ruminants for fattening, feed drugs of new generation adsorbents are increasingly and widely introduced. They often exhibit synergistic eff ects on metabolic processes with a large set of biologically active additives including enzyme drugs. The purpose of the research was to study the infl uence of the adsorbent drugs toxfi n and MEC celloviridin G20x on the state of rumen metabolism in fattening steers in whose diets there was an excess content of lead, zinc and cadmium salts. It was found that in order to activate the processes of digestive metabolism due to better elimination of heavy metal salts, it is advisable to jointly introduce the adsorbent toxfi n in the amount of 1 kg/t of compound feed and MEC celloviridin G20x in the amount of 70 g/t of compound feed into the composition of the rations of fattening steers. The results of the conducted studies showed that by the end of fattening at the age of 18 months the animals of the 4th experimental group had the highest body weight, which surpassed the steers of the 1st control group by 29.20 kg (p < 0.05) or 6.86 %. Relative to the control analogues the steers of the 4th experimental group showed an activation of growth in the forestomachs of ciliates (producers of cellulases and amylases) by 54.26 % (p < 0.05) and bacteria of the Flavobacterium vitarumen group (producers of proteinases) by 29.36 % (p < 0.05). Due to the combined feeding of the adsorbent drugs toxfi n and MEC celloviridin G20x, the processes of detoxifi cation of heavy metal salts were more effective. Therefore, the fattening steers of the 4th experimental group more actively accumulated volatile fatty acids in the rumen fl uid, significantly (p < 0.05) outperforming the animals of the 1st control group in this indicator by 1.68 mmol/100 ml or by 20.71 %.

Zinc Protects against Swine Barn Dust-Induced Cilia Slowing.

Agricultural workers exposed to organic dust from swine concentrated animal feeding operations (CAFOs) have increased chances of contracting chronic lung disease. Mucociliary clearance represents a first line of defense against inhaled dusts, but organic dust extracts (ODEs) from swine barns cause cilia slowing, leading to decreased bacterial clearance and increased lung inflammation. Because nutritional zinc deficiency is associated with chronic lung disease, we examined the role of zinc supplementation in ODE-mediated cilia slowing. Ciliated mouse tracheal epithelial cells were pretreated with 0-10 µg/mL ZinProTM for 1 h, followed by treatment with 5% ODE for 24 h. Cilia beat frequency (CBF) and protein kinase C epsilon (PKCε) activity were assayed. ODE treatment resulted in cilia slowing after 24 h, which was reversed with 0.5 and 1.0 µg/mL ZinPro pre-treatment. No zinc protection was observed at 50 ng/mL, and ciliated cells detached at high concentrations (100 µg/mL). ZinPro alone produced no changes in the baseline CBF and showed no toxicity to the cells at concentrations of up to 10 µg/mL. Pre-treatment with ZinPro inhibited ODE-stimulated PKCε activation in a dose-dependent manner. Based on ZinPro's superior cell permeability compared to zinc salts, it may be therapeutically more effective at reversing ODE-mediated cilia slowing through a PKCε pathway. These data demonstrate that zinc supplementation may support the mucociliary transport apparatus in the protection of CAFO workers against dust-mediated chronic lung disease.

Unveiling the Failure Mechanism of Zn Anodes in Zinc Trifluorosulfonate Electrolyte: The Role of Micelle-like Structures.

Zinc trifluorosulfonate [Zn(OTf)2] is considered as the most suitable zinc salt for aqueous Zn-ion batteries (AZIBs) but cannot support the long-term cycling of the Zn anode. Here, we reveal the micelle-like structure of the Zn(OTf)2 electrolyte and reunderstand the failing mechanism of the Zn anode. Since the solvated Zn2+ possesses a positive charge, it can spontaneously attract OTf- with the hydrophilic group of -SO3 and the hydrophobic group of -CF3 via electrostatic interaction and form a "micelle-like" structure, which is responsible for the poor desolvation kinetics and dendrite growth. To address these issues, an antimicelle-like structure is designed by using ethylene glycol monomethyl ether (EGME) as a cosolvent for highly reversible AZIBs. The modified electrolyte shows lower dissociation ability to Zn(OTf)2 and higher coordination tendency with Zn2+ compared to the Zn(OTf)2 electrolyte, resulting in the unique solvation structure of Zn2+(H2O)1.2(OTf-)2(EGME)2.8, which significantly reduces the charge of micelle, damages the micelle-like structure, and boosts the desolvation kinetics. Moreover, the reduction of EGME and OTf- can form a robust dual-layered SEI with high Zn2+ ion conductivity. Consequently, the Zn/Cu asymmetric coin cell using ZT-EGME can work at a high rate and a capacity of 50 mA cm-2 and 5 mA h cm-2 for more than 120 cycles, while its counterparts using ZT can barely work. Moreover, a 505.1 mA h pouch cell with practical parameters including a lean electrolyte supply of 15 mL A h-1 and an N/P ratio of ∼3.5 can work for 50 cycles.

Unlocking the performance degradation of vanadium-based cathodes in aqueous zinc-ion batteries

Vanadium-based materials stand out as promising cathode options for rechargeable aqueous zinc-ion batteries (ZIBs), primarily because of their high capacity and superior rate capability. Nevertheless, the utilization of vanadium-based cathodes in advancing ZIBs toward commercial viability is hindered by their insufficient stability and a notable lack of comprehension of the mechanisms driving capacity degradation. Herein, we identified the formation of Zn3(OH)2V2O7·2H2O (ZOV) as a key contributor to the capacity decay of vanadium-based cathodes. Through a series of compelling experiments, we revealed that dissolved vanadium ions react with zinc salts or layered zinc hydroxide (formed from H+ insertion) during the immersion or cycling of vanadium-based cathodes in aqueous electrolytes, ultimately leading to the formation of detrimental ZOV. Strong evidence shows that ZOV is inactive for Zn2+ storage owing to the presence of the pure tetrahedral frameworks of vanadium. To suppress the formation of ZOV, adjustments were made to the electrolyte composition, including the solvents and solutes. Consequently, the absence of ZOV enables an impressive capacity retention of 85 % in the ZnSO4 electrolyte after 150 cycles at 0.2 A g−1. Overall, this study directly unlocks the capacity decay mechanism in vanadium-based cathodes and offers valuable insights for the design of innovative electrolytes and novel vanadium-based cathode materials for ZIBs.

Density of lymphocytes in cortex and medulla substance of thymus particles of white rats in normal conditions and under influence of heavy metal salts during three months

The consumption of clean water is the most relevant today, but natural water is delivered to our homes through plastic, iron and galvanized pipes. Metal ions, which are part of the pipe material, can get into drinking water and affect the human body, in particular the thymus. That is why the aim of the work was to determine the density of large, medium and small lymphocytes in the cortex and medulla of the thymus lobules of outbred white male rats of reproductive age when consuming small doses of heavy metal salts with water for three months. The study was conducted on 40 outbred white male rats of reproductive age, which were divided into 4 groups: 1 group – control animals that consumed distilled water; 2 group of animals that consumed aqueous solutions – CuSO4·5H2O at a dose of 0.247 mg/dm3; 3 group – aqueous solution of ZnSO4·7H2O at a dose of 1.505 mg/dm3; group 4 – aqueous solution of FeSO4·7H2O at a dose of 0.5 mg/dm3. Histological, electron microscopic and morphometric research methods were used to study the density of large, medium and small lymphocytes in different zones of the thymus lobules. It was found that in the control group of rats, the density of large lymphocytes is the highest in the subcapsular zone, and the lowest in the medulla. The density of medium lymphocytes is the lowest in the subcapsular zone. The density of small lymphocytes is the lowest in the medulla, and the highest in the cortico-medullary zone. When using CuSO4·5H2O salts with drinking water for three months, there were no significant changes in the density of lymphocytes compared to the control group, except for a slight decrease in the density of large lymphocytes in the cortex of the thymus lobules. The density of lymphocytes in the third group of animals that consumed zinc salts (ZnSO4·7H2O) with drinking water changes significantly: the density of large lymphocytes in the subcapsular zone decreases by 2.3 times, in the cortico-medullary zone it increases by 4.7 times, and in the medulla it increases by 2.7 times; the density of medium lymphocytes decreases in the subcapsular zone by 2 times; the density of small lymphocytes decreases by 1.5 times in the subcapsular zone, in the cortex and cortico-medullary zone – decreases by 1.2 times, and in the medulla by 1.1 times. When using FeSO4·7H2O salts with drinking water for three months, no special changes in the density of lymphocytes were noted: a decrease in the density of large lymphocytes in the subcapsular zone by 1.5 times and by 1.3 times in the cortex was observed; the density of medium lymphocytes decreases by 1.2 times in the cortex, and the density of small lymphocytes decreases by 1.2 times in the subcapsular zone and cortex, and increases by 1.2 times in the medulla, compared to the control group of animals. Ultrastructural changes in the structure of lymphocytes and reticuloepithelial cells were not detected when heavy metal salts were consumed with water. Thus, the study showed that the most toxic for the body are zinc salts (ZnSO4·7H2O), the consumption of which with drinking water in small doses for three months led to significant changes in the density of lymphocytes, compared to the control group experimental animals.

Explorations on the antiviral potential of zinc and magnesium salts against chikungunya virus: implications for therapeutics.

Chikungunya virus (CHIKV), which causes chikungunya fever, is an arbovirus of public health concern with no approved antiviral therapies. A significant proportion of patients develop chronic arthritis after an infection. Zinc and magnesium salts help the immune system respond effectively against viral infections. This study explored the antiviral potential of zinc sulphate, zinc acetate, and magnesium sulphate against CHIKV infection. The highest non-toxic concentration of the salts (100 µM) was used to assess the prophylactic, virucidal, and therapeutic anti-CHIKV activities. Dose-dependent antiviral effects were investigated to find out the 50% inhibitory concentration of the salts. Entry bypass assay was conducted to find out whether the salts affect virus entry or post entry stages. Virus output in all these experiments was estimated using a focus-forming unit assay, real-time RT-PCR, and immunofluorescence assay. Different time- and temperature-dependent assays revealed the therapeutic antiviral activity of zinc and magnesium salts against CHIKV. A minimum exposure of 4 hours and treatment initiation within 1 to 2 hours of infection are required for inhibition of CHIKV. Entry assays revealed that zinc salt affected virus-entry. Entry bypass assays suggested that both salts affected post-entry stages of CHIKV. In infected C57BL6 mice orally fed with zinc and magnesium salts, a reduction in viral RNA copy number was observed. The study results suggest zinc salts exert anti-CHIKV activity at entry and post entry stages of the virus life cycle, while magnesium salt affect CHIKV at post entry stages. Overall, the study highlights the significant antiviral potential of zinc sulphate, zinc acetate, and magnesium sulphate against CHIKV, which can be exploited in designing potential therapeutic strategies for early treatment of chikungunya patients, thereby reducing the virus-associated persistent arthritis.

From waste to added-value product: A case of efficient separation and recovery of zinc and iron from spent galvanizing acid

Spent galvanizing acid solution contains high concentrations of zinc salts, ferrous salts, and residual acids, exhibiting extremely high value-added recovery potential. However, achieving the efficient extraction and separation of Zn over Fe becomes particularly challenging under elevated Zn ion concentration. Here, the key extraction parameters, such as modifier ratio, Cyanex 923 concentration and ratio of organic phase to aqueous phase (O/A), are investigated. The stripping and regeneration of extractant, extraction mechanism, as well as high-value recovery of Zn and Fe resources are also comprehensively expounded. After the two-stage extraction, the extraction efficiency of Zn and Fe is 98.92 ​% and 2.09 ​%, respectively. Moreover, the stripping efficiency of Zn reaches 92.3 ​% with O/A ratio of 1 : 2, using oxalic acid as stripping agent. The predominant extracted species is confirmed to be ZnCl3−, resulting in the formation of HZnCl3∙R3PO complex. More importantly, the regenerated extractant can be recycled back into the extraction process, and the reproduced HCl, high-value recovered ZnO and Fe2O3 can be used for different industrial fields. These findings lay a solid foundation for the efficient separation and comprehensive recovery of high-concentration spent galvanizing acid solution.

Characteristics of patients with Wilson disease in the United States: An insurance claims database study.

Wilson disease (WD) is a progressive, potentially fatal degenerative disease affecting the liver and central nervous system. Given its low prevalence, collecting data on large cohorts of patients with WD is challenging. Comprehensive insurance claims databases provide powerful tools to collect retrospective data on large numbers of patients with rare diseases. To describe patients with WD in the United States, their treatment and clinical outcome, using a large insurance claims database. This retrospective, longitudinal study was performed in the Clarivate Real-World Data Product database. All patients with ≥ 2 claims associated with an International Classification of Diseases 10 (ICD-10) diagnostic code for WD (E83.01) between 2016 and 2021 were included and followed until death or study end. Patients were divided into two groups by whether or not they were documented to have received a specific treatment for WD. Clinical manifestations, hospitalisations, liver transplantation and death were documented. Overall, 5376 patients with an ICD-10 diagnostic code for WD were identified. The mean age at inclusion was 41.2 years and 52.0% were men. A specific WD treatment was documented for 885 patients (15.1%), although the number of patients taking zinc salts may be underestimated due to over the counter purchase. At inclusion, the mean age of patients with a documented treatment was 36.6 ± 17.8 years vs 42.2 ± 19.6 years in those without a documented treatment. During follow-up, 273 patients (5.1%) died. Compared with the American general population, the standardised mortality ratio was 2.19. The proportion of patients with a documented WD-specific treatment who died during follow-up was 4.0% and the mean age at death 52.7 years. Patients treated for WD in the United States had an excess early mortality compared with the American population. These findings indicate that there is a significant unmet need for effective treatment for WD in the United States.

Hydrated eutectic electrolyte promotes the preferential growth of Zn (0 0 2) plane and suppresses side reaction for high-stability zinc anodes

Using deep eutectic solvent (DES) electrolytes is an efficient way to suppress the Zn dendrite growth and the side reactions resulting from the high activity of H2O in aqueous zinc-ion batteries (ZIBs). However, most DESs consist of expensive/explosive zinc salts or flammable/toxic organic ligands, which hinders their practical application in ZIBs. Herein, a low-cost and high-safety hydrated eutectic electrolyte based on ZnCl2, urea, and a small amount of H2O is prepared. Due to the low content of H2O and the strong intermolecular interaction between urea and H2O, the activity of H2O is greatly restricted and therefore H2O-induced side reactions are improved. In addition, X-ray photoelectron spectroscopy spectra and density functional theory calculations reveal that the adsorption of urea molecules on the zinc surface forms an organic protective layer, which can induce the preferential growth of the Zn (0 0 2) plane. As a result, with the optimal electrolyte, the Zn||Zn symmetric cell shows a long cyclic life of 1200 h, and the Zn||Cu half-cell delivers a high average Coulombic efficiency of 99.7 % for 2500 cycles. Meanwhile, the Zn||Bi2Te3 and Zn||polyaniline full cells with DES exhibit improved cycling performances compared to those using traditional ZnSO4 electrolyte. This work offers a new perspective to explore low-cost, non-toxic, and high-security DESs for ZIBs.

Upgrading Gel Electrolytes Through Electrostatic-Induced Dual-Salt Paradigm for Superior Zn-Ion Battery Performance.

Gel electrolytes are gaining attention for rechargeable Zn-ion batteries because of their high safety, high flexibility, and excellent comprehensive electrochemical performances. However, current gel electrolytes still perform at mediocre levels due to incomplete Zn salts dissociation and side reactions. Herein, an electrostatic-induced dual-salt strategy is proposed to upgrade gel electrolytes to tackle intrinsic issues of Zn metal anodes. The competitive coordination mechanism driven by electrostatic repulsion and steric hindrance of dual anions promotes zinc salt dissociation at low lithium salt addition levels, improving ion transport and mechanical properties of gel electrolytes. Li+ ions and gel components coordinate with H2O, reducing active H2O molecules and inhibiting associated side reactions. The dual-salt gel electrolyte enables excellent reversibility of Zn anodes at both room and low temperatures. Zn||Polyaniline cells using the dual-salt gel electrolyte exhibit a high discharge capacity of 180mAhg-1 and long-term cycling stability over 180 cycles at -20°C. The dual-salt strategy offers a cost-effective approach to improving gel electrolytes for high-performance flexible Zn-ion batteries.

ZIF-8 Used for the Selective Recovery of Heavy Rare Earth Elements from Mining Wastewater.

In this study, a sample of 2-methylimidazole zinc salt (ZIF-8) demonstrated high selectivity for the recovery of heavy rare earth elements (REEs) from real rare earth mining wastewater. Results show that the distribution coefficient values of Y3+ (4.02 × 104 mL·g-1), Gd3+ (7.8 × 104 mL·g-1), and Dy3+ (6.8 × 104 mL·g-1) are orders of magnitude higher than those of K+ (359.51 mL·g-1), Mn2+ (266.67 mL·g-1), Ca2+ (396.42 mL·g-1), and Mg2+ (239.48 mL·g-1). Moreover, the desorption efficiency of heavy REEs exceeded 40%. Advanced characterizations and density functional theory (DFT) calculations were utilized to elucidate that the heavy REEs were more likely to bind to the nitrogen atoms of imidazole groups on ZIF-8 compared to non-REEs. Furthermore, the adsorption and desorption of heavy REEs primarily depend on the chemical interaction confirmed by adsorption kinetics, isotherm model, and thermodynamic analysis, which involves the dissociation of water and the formation of REE-O bonds. Finally, the ZIF-8 exhibits a remarkable recovery efficiency of over 40% for heavy REEs in column tests conducted over 7h. The findings reported here provide new insights into the selective recovery of heavy REEs from real mining wastewater.

The Influence of Zinc Oxide Nanoparticles and Salt Stress on the Morphological and Some Biochemical Characteristics of Solanum lycopersicum L. Plants.

Salinity reduces crop yields and quality, causing global economic losses. Zinc oxide nanoparticles (ZnO-NPs) improve plant physiological and metabolic processes and abiotic stress resistance. This study examined the effects of foliar ZnO-NPs at 75 and 150 mg/L on tomato Kecskeméti 549 plants to alleviate salt stress caused by 150 mM NaCl. The precipitation procedure produced ZnO-NPs that were characterized using UV-VIS, TEM, STEM, DLS, EDAX, Zeta potential, and FTIR. The study assessed TPCs, TFCs, total hydrolyzable sugars, total free amino acids, protein, proline, H2O2, and MDA along with plant height, stem width, leaf area, and SPAD values. The polyphenolic burden was also measured by HPLC. With salt stress, plant growth and chlorophyll content decreased significantly. The growth and development of tomato plants changed by applying the ZnO-NPs. Dosages of ZnO-NPs had a significant effect across treatments. ZnO-NPs also increased chlorophyll, reduced stress markers, and released phenolic chemicals and proteins in the leaves of tomatoes. ZnO-NPs reduce salt stress by promoting the uptake of minerals. ZnO-NPs had beneficial effects on tomato plants when subjected to salt stress, making them an alternate technique to boost resilience in saline soils or low-quality irrigation water. This study examined how foliar application of chemically synthesized ZnO-NPs to the leaves affected biochemistry, morphology, and phenolic compound synthesis with and without NaCl.

Eco-friendly guar gum composites as solid-state electrolytes

Solid-state Guar gum electrolytes were prepared through the solution casting technique, employing a composition of 70 % Guar gum and 30 % ZnSO4·7H2O(GZ3). Different weight concentrations of nano ZrO2 (2.5 %, 5 %, 7.5 %, and 10 %) were introduced into the present Guar gum electrolytes. As prepared ZrO2 nanofiller substituted Guar gum electrolytes were examined by XRD, FTIR, DSC, and SEM to evaluate the amorphous characteristics, complexation, glass transition temperature, and surface morphology, respectively. Electrochemical impedance was utilized to examine the frequency-dependent ionic conductivity and dielectric properties of prepared ZrO2 nanofiller-substituted Guar gum electrolytes. At a temperature of 100 °C, the Guar gum electrolyte with10 % Nano ZrO2 exhibited an ionic conductivity of 3.19 × 10−3 S/cm, whereas, at room temperature (RT), it recorded a value of 1.09 × 10−3 S/cm. The activation energy for these electrolytes varied within the range of 0.26 eV–0.39 eV. Furthermore, an investigation of the frequency-dependent dielectric properties revealed a significant tail in the low-frequency region and the presence of space charge polarization within the electrolyte. The study also explored the relaxation time and hopping mechanism through dielectric modulus parameters. Moreover, a flexible Zn-based electrochemical cell was fabricated using a formulation comprising 70 % Guar gum, 30 % Zinc salt, and 10 % Nano ZrO2. The outcomes revealed an open circuit voltage of 0.82V, a discharge rate of 0.04C sustained over 25 h, with an average current discharge rate of approximately 1.4 mA per hour, resulting in an electrochemical-specific capacity of around 45mAh/g. Additionally, a solar cell device was fabricated using Guar gum electrolytes, and the photovoltaic parameters were computed. The maximum overall power conversion efficiency (ƞ) reached 4.79, with short-circuit photocurrent density (Jsc) at 9.66 mA/cm2, open-circuit voltage (Voc) at 725 mV, and fill factor (FF) at 0.65.

Impact of copper and zinc oral chronic exposure on Carniolan honey bee survival and feeding preference.

Honey bees are important plant pollinators and honey producers. Contamination of the environment with metals can lead to a decline in honey bee populations. Copper (Cu) and zinc (Zn) salts are commonly used as fungicides and foliar fertilizers. In this study, we investigated the effects of 10-day chronic oral exposure to different concentrations of Cu (CuSO4) and Zn (ZnCl2) on survival and feeding rates of Carniolan honey bees in laboratory conditions. We found that mortality in honey bee workers increased in a concentration-dependent manner and that Cu (lethal concentration [LC50] = 66 mg/l) was more toxic than Zn (LC50 = 144 mg/l). There was no difference in the feeding rate of Cu-treated bees for the different concentrations tested, but the feeding rate decreased with the increase in Zn concentration. To determine feeding preference or avoidance for Cu and Zn, we conducted 2-choice 24-h feeding experiments. We demonstrated that honey bees preferred Zn-containing solutions compared to the control diet. A two-choice experiment with Cu showed a tendency for honey bees to be deterred by Cu at high concentrations; however, it was not statistically significant. In summary, our results suggest that honey bee workers may suffer adverse effects when exposed to ecologically relevant concentrations of Cu and Zn.

Responses of bread wheat to Zn-Glycine and Zn-Alanine fertilizers under saline soil condition

Zinc (Zn) deficiency and salt stress are well-known soil problems and often happen parallelly in cultivated soils. In this study, Zn-amino acid complexes (Zn-AAc) were used as a source of Zn to determine their effects on salt-induced damage in wheat plants. The bread wheat (Triticum aestivum L. cvs. Kavir) was supplied with Zn-glycine (Zn-Gly), Zn-alanine (Zn-Ala), and ZnSO4 as Zn sources at three salinity levels (EC 2, 4 and 6 dS m-). Salinity caused a significant decrease in shoot dry matter and grain yield of wheat, but this negative effect was significantly improved by the application of Zn-AAc. Salt stress decreased shoot and grain Zn concentration, but this reduction was lower in plants supplied by Zn-AAc. Calcium (Ca) and potassium (K) concentrations were increased in a shoot by salinity stress while decreased in grain. Sodium (Na) concentration decreased in shoot and grain by using Zn-AAc. At all of the salinity levels, wheat supplied with Zn-AAc had lower lipid peroxidation compared to those grown under the ZnSO4 source. Application of Zn-AAc increased the activities of catalase (CAT) and superoxide dismutase (SOD) in the roots of wheat plants in saline conditions. Based on the results, the adverse effects of salinity stress on wheat plants can moderately improve with Zn-AAc application.

Layer‑by‑layer assembled binder-free hydrated vanadium oxide-acetylene black electrode for flexible aqueous zinc ion battery

Vanadium oxides are potential positive electrode materials for aqueous zinc ion batteries (ZIBs) owing to their advantages of high theoretical capacity, low cost, and so on. Developments of methods for preparing binder-free vanadium oxide electrodes on a large scale and further investigation of their Zn2+ storage mechanisms are essential for expanding their uses in large-scale energy storage systems and wearable electronics. In this work, binder-free electrodes with hydrated vanadium oxide (V2O5·nH2O, denoted as VOH)-acetylene black (AB) on carbon cloth (VOH-AB/CC) are fabricated by a simple and scalable method which combined low-temperature hydrothermal treatment with layer-by-layer drop/spray-coating process. The AB can greatly improve the electrical conductivity of VOH, thereby enhancing the electrochemical performance. The as-prepared electrode with 20 wt% of AB (VOH-AB2/CC) delivers a high capacity of 280 mA h g−1 at 1 A/g and a good rate capability of 205 mA h g−1 at 4 A/g, which is better than many of the reported binder-free vanadium base electrodes. Besides, excellent cycling performance with 89 % retention rate after 3000 cycles at 4 A/g is achieved on the VOH-AB2/CC electrode. Furthermore, a storage mechanism of Zn2+/H+/H2O insertion accompanied by the formation of basic zinc salt precipitate during the discharging process is proposed by the aid of ex-situ XRD and XPS techniques. Additionally, the flexible Quasi-Solid-State ZIB constructed using VOH-AB/CC as positive electrode can work well at different bending states and two ZIBs connected in series can lighten a light-emitting diode even under bending state. This work provides a low-cost, time-saving, environmental-friendly and scalable method to fabricate binder-free hydrated vanadium oxide electrodes for flexible aqueous ZIBs.

Potential efficacy of bimetallic nanoparticles synthesized from extracellular cell-free extract of Penicillium citrinum against Culex quinquefasciatus mosquito larvae, and their photocatalytic activity

The biological synthesis of nanoparticles finds application in the development of novel insecticides and bioremediation agents. In this study, bimetallic nanoparticles were synthesized using copper and zinc salts along with Penicillium citrinum secondary metabolite. The synthesized nanoparticles were analyzed for their insecticidal and photocatalytic efficacy on Culex quinquefasciatus larvae and organic dyes, respectively. The synthesized nanoparticles were characterized by UV spectroscopy, FTIR, XRD, SEM, EDX, and HR-TEM. The results showed fungal metabolite synthesized bimetallic nanoparticles were too toxic for Culex quinquefasciatus larvae, with LC50 and LC90 values of 1016.51 ppm, 4948.12 ppm for 24 h exposure; 184.80 ppm, 718.16 ppm for 48 h exposure, and 59.07 and 338.76 ppm for 72 h exposure, respectively. The Cu–Zn bimetallic nanoparticles showed mild photocatalytic activity on Xylenol orange (36%). This study shows that bimetallic NPs synthesized from Penicillium citrinum are advantageous for mosquito control as well as having photocatalytic dye degradation properties.

Effect of Banana Peels Extract Ratio on The Sustainable Eco-Friendly Synthesis of Zinc Oxide Nanoparticles

In this work, environmentally friendly zinc oxide nanoparticles was produced using sustainable green technology. With several loading amounts, such as 5%, 10%, 50%, and 100%, the banana peel extract was utilized as a capping agent. This was followed by calcinations at 400 ºC for 3 h in a muffle furnace. To evaluate the physical and chemical change of the synthesized nanoparticles, XRD, FTIR, UV-VIS and SEM/EDAX was used. The characterization results reveald that the all the green synthesized ZnO NPs samples strongly supports the well-crystallinity with high phase purity. The average crystallite size of the prepared samples was calculated using Debye-Scherer's formula and the results shows that with an increase in extract amount, the average crystallite size was shrinking. The FTIR result verified the successful chemical reaction between zinc salt and banana peel extract. The UV-VIS results showed the effect of size quantisization phenomena at 100% extract adding. Finally, the SEM images for all the prepared samples confirm the spherical shape.