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ACS Applied Materials & Interfaces Jun 2024MnO-based materials have limited capacity and poor conductivity over various voltages, hampering their potential for energy storage applications. This work proposes a...
MnO-based materials have limited capacity and poor conductivity over various voltages, hampering their potential for energy storage applications. This work proposes a novel approach to address these challenges. A self-oriented multiple-electronic structure of a 1D-MnO-nanorod/2D-MnO-nanosphere composite was assembled on 2D-graphene oxide nanosheet/1D-carbon nanofiber (GO/CNF) hybrids. Aided by K ions, the MnO nanorods were partially converted to MnO nanospheres, while the GO nanosheets were combined with CNF through hydrogen bonds resulting in a unique double binary 1D-2D mixed morphology of MnO/MnO-GO/CNF hybrid, having a novel mechanism of multiple Mn ion redox reactions facilitated by the interconnected 3D network. The morphology of the MnO nanorods was controlled by regulating the potassium ion content through a rinsing strategy. Interestingly, pure MnO nanorods undergo air-annealing to form a mixture of nanorods and nanospheres (MnO/MnO) with a distinct morphology indicating pseudocapacitive surface redox reactions involving Mn, Mn, and Mn. In the presence of the GO/CNF framework, the charge storage properties of the MnO/MnO-GO/CNF composite electrode show dominant battery-type behavior because of the unique mesoporous structure with a crumpled morphology that provides relatively large voids and cavities with smaller diffusion paths to facilitate the accumulation/intercalation of charges at the inner electroactive sites for the diffusion-controlled process. The corresponding specific capacity of 800 C g or 222.2 mAh g at 1 A g and remarkable cycling stability (95%) over 5000 cycles at 3 A g were considerably higher than those of the reported electrodes of similar materials. Moreover, a hybrid supercapacitor device is assembled using MnO/MnO-GO/CNF as the positive electrode and activated carbon as the negative electrode, which exhibits a superior maximum energy density (∼25 Wh kg) and maximum power density (∼4.0 kW kg). Therefore, the as-synthesized composite highlights the development of highly active low-cost materials for next-generation energy storage applications.
PubMed: 38940603
DOI: 10.1021/acsami.4c03109 -
Chemical Science Jun 2024Alkali metal alkoxides play a pivotal role in nucleophilic alkoxylation reactions, offering pathways for the synthesis of ethers, including the increasingly sought-after...
Alkali metal alkoxides play a pivotal role in nucleophilic alkoxylation reactions, offering pathways for the synthesis of ethers, including the increasingly sought-after trifluoromethyl ethers. However, the synthesis of long-chain perfluoroalkyl ethers remains a substantial challenge in this field. Through the innovative use of triglyme to encapsulate potassium ions, we enhanced the stability of short-lived, longer-chain perfluoroalkoxy anions, thereby facilitating efficient nucleophilic perfluoroalkoxylation reactions. This method provides a new precedent for the halo-perfluoroalkoxylation of -difluoroalkenes and offers a versatile tool for the design of perfluoroalkyl ethers, including those containing complex moieties of heterocycles and drug molecules. We also demonstrated the utility of the resulting halo-perfluoroalkoxyl adducts through various chemical transformations to valuable diverse perfluoroalkyl ethers.
PubMed: 38939153
DOI: 10.1039/d4sc02084g -
Organometallics Jun 2024Rubidium and cesium are the least studied naturally occurring s-block metals in organometallic chemistry but are in plentiful supply from a sustainability viewpoint as...
Rubidium and cesium are the least studied naturally occurring s-block metals in organometallic chemistry but are in plentiful supply from a sustainability viewpoint as highlighted in the periodic table of natural elements published by the European Chemical Society. This underdevelopment reflects the phenomenal success of organometallic compounds of lithium, sodium, and potassium, but interest in heavier congeners has started to grow. Here, the synthesis and structures of rubidium and cesium bis(amido)alkyl magnesiates [(AM)MgN'alkyl], where N' is the simple heteroamide N(SiMe)(Dipp), and alkyl is Bu or CHSiMe, are reported. More stable than their Bu analogues, the reactivities of the CHSiMe magnesiates toward 1,4-cyclohexadiene are revealed. Though both reactions produce target hydrido-magnesiates [(AM)MgN'H] in crystalline form amenable to X-ray diffraction study, the cesium compound could only be formed in a trace quantity. These studies showed that the bulk of the N(SiMe)(Dipp) ligand was sufficient to restrict both compounds to dimeric structures. Bearing some resemblance to inverse crown complexes, each structure has [(AM)(N)(Mg)(N)] ring cores but differ in having no AM-N bonds, instead Rb and Cs complete the rings by engaging in multihapto interactions with Dipp π-clouds. Moreover, their hydride ions occupy μ-(AM)Mg environments, compared to μ-Mg environments in inverse crowns.
PubMed: 38938897
DOI: 10.1021/acs.organomet.4c00190 -
Scientific Reports Jun 2024Pomegranate (Punica granatum L.) fruit quality depends on many traits including visual, biochemical and mineral characteristics. One of the negative traits is aril...
Pomegranate (Punica granatum L.) fruit quality depends on many traits including visual, biochemical and mineral characteristics. One of the negative traits is aril whitening (AW) which is a frequently observed disorder in hot and dry climates, that leads to decline in desirable fruit quality. Color, antioxidant, and mineral contents of the arils are of prime importance as quality traits. Therefore, this study aims to investigate the effect of shading and foliar minerals on fruit quality during the fruit development stages of pomegranate. Treatments included shaded (50% green net) and unshaded trees and foliar application of trees with potassium sulfate (K, 1% and 2%) or sodium silicate (Si, 0.05, 0.1 and 0.15%) during two growing seasons. Results showed that the severity of AW at harvest decreased significantly when trees were covered with shading compared to control. The color values of L* and ⁰hue for arils were lower in fruits grown under shading conditions indicating darker red arils. Shading significantly reduced chilling injury in cold storage compared to open field fruits. Shading and Si 0.15% increased superoxide dismutase, and catalase enzymes activity while decreased Polyphenol oxidase and peroxidase. Covering trees with shading and Si 0.15% spray resulted in the highest total anthocyanin, antioxidant activity, and total phenolics content in the arils. Shading as well as Si 0.15% increased macronutrients content of the arils. The study concluded that covering pomegranate trees and spraying with Si in hot climate reduced AW, increased antioxidant traits, and led to higher fruit quality.
Topics: Antioxidants; Fruit; Pomegranate; Silicates; Sulfates; Minerals; Color; Anthocyanins
PubMed: 38937529
DOI: 10.1038/s41598-024-65084-3 -
Molecular & Cellular Proteomics : MCP Jun 2024Microglia are resident immune cells of the brain and regulate its inflammatory state. In neurodegenerative diseases, microglia transition from a homeostatic state to a...
Microglia are resident immune cells of the brain and regulate its inflammatory state. In neurodegenerative diseases, microglia transition from a homeostatic state to a state referred to as disease associated microglia (DAM). DAM express higher levels of proinflammatory signaling molecules, like STAT1 and TLR2, and show transitions in mitochondrial activity toward a more glycolytic response. Inhibition of Kv1.3 decreases the proinflammatory signature of DAM, though how Kv1.3 influences the response is unknown. Our goal was to identify the potential proteins interacting with Kv1.3 during transition to DAM. We utilized TurboID, a biotin ligase, fused to Kv1.3 to evaluate potential interacting proteins with Kv1.3 via mass spectrometry in BV-2 microglia following TLR4-mediated activation. Electrophysiology, western blotting, and flow cytometry were used to evaluate Kv1.3 channel presence and TurboID biotinylation activity. We hypothesized that Kv1.3 contains domain-specific interactors that vary during a TLR4-induced inflammatory response, some of which are dependent on the PDZ-binding domain on the C-terminus. We determined that the N-terminus of Kv1.3 is responsible for trafficking Kv1.3 to the cell surface and mitochondria (e.g. NUDC, TIMM50). Whereas, the C-terminus interacts with immune signaling proteins in an LPS-induced inflammatory response (e.g. STAT1, TLR2, and C3). There are 70 proteins that rely on the C-terminal PDZ-binding domain to interact with Kv1.3 (e.g. ND3, Snx3, and Sun1). Furthermore, we used Kv1.3 blockade to verify functional coupling between Kv1.3 and interferon-mediated STAT1 activation. Overall, we highlight that the Kv1.3 potassium channel functions beyond conducting the outward flux of potassium ions in an inflammatory context and that Kv1.3 modulates the activity of key immune signaling proteins, such as STAT1 and C3.
PubMed: 38936775
DOI: 10.1016/j.mcpro.2024.100809 -
Journal of Environmental Radioactivity Jun 2024After the Fukushima Daiichi nuclear power plant accident, the terrestrial environment became severely contaminated with radiocesium. Consequently, the river and lake...
After the Fukushima Daiichi nuclear power plant accident, the terrestrial environment became severely contaminated with radiocesium. Consequently, the river and lake water in the Fukushima area exhibited high radiocesium levels, which declined subsequently. The partition coefficient of Cs between the suspended sediment (SS) and dissolved phases, K, was introduced to better understand the dynamic behavior of Cs in different systems. However, the K values in river water, ranging from 2 × 10 to 7 × 10 L kg, showed large spatiotemporal variability. Therefore, the factors controlling the Cs partition coefficient in natural water systems should be identified. Herein, we introduce a chemical model to explain the variability in Cs K in natural water systems. The chemical model includes the complexation of Cs with mineral and organic binding sites in SS, metal exchange reactions, and the presence of colloidal species. The application of the chemical model to natural water systems revealed that Cs is strongly associated with binding sites in SS, and a major chemical interaction between Cs and the binding sites in SS is the isotope exchange reaction between stable Cs and Cs, rather than metal exchange reactions with other metal ions such as potassium ions. To explain the effect of the SS concentration on K, the presence of colloidal Cs passing through a filter is significant as the dominant dissolved species of Cs in river water. These results suggest that a better understanding of stable Cs dissolved in natural water is important for discerning the geochemical and ecological behaviors of Cs in natural water.
PubMed: 38936250
DOI: 10.1016/j.jenvrad.2024.107486 -
Journal of Water and Health Jun 2024Ferrate (Fe(VI): HFeO /FeO), a potent oxidant, has been investigated as an alternative chemical disinfectant in water treatment due to its reduced production of...
Ferrate (Fe(VI): HFeO /FeO), a potent oxidant, has been investigated as an alternative chemical disinfectant in water treatment due to its reduced production of disinfection by-products. In this study, we assessed the disinfecting ability of potassium ferrate against a variety of microorganisms, including waterborne pathogens, under varying pH and water temperature conditions. We presented CT values, a metric of ferrate concentrations (C) and contact time (T), to quantify microbial inactivation rates. Among the tested microorganisms, human adenovirus was the least resistant to ferrate, followed by waterborne bacteria such as and , and finally, the protozoan parasite . We further investigated the impact of two pH values (7 and 8) and two temperatures (5 and 25 °C) on microbial inactivation rates, observing that inactivation rates increased with lower pH and higher temperature. In addition to showcasing ferrate's capacity to effectively inactivate a range of the tested microorganisms, we offer a ferrate CT table to facilitate the comparison of the effectiveness of various disinfection methods.
Topics: Hydrogen-Ion Concentration; Temperature; Disinfectants; Giardia lamblia; Adenoviruses, Human; Potassium Compounds; Water Microbiology; Disinfection; Water Purification; Iron Compounds; Humans; Escherichia coli
PubMed: 38935460
DOI: 10.2166/wh.2024.087 -
Plants (Basel, Switzerland) Jun 2024Enhancing root development is pivotal for boosting crop yield and augmenting stress resilience. In this study, we explored the regulatory effects of xylooligosaccharides...
Enhancing root development is pivotal for boosting crop yield and augmenting stress resilience. In this study, we explored the regulatory effects of xylooligosaccharides (XOSs) on lettuce root growth, comparing their impact with that of indole-3-butyric acid potassium salt (IBAP). Treatment with XOS led to a substantial increase in root dry weight (30.77%), total root length (29.40%), volume (21.58%), and surface area (25.44%) compared to the water-treated control. These enhancements were on par with those induced by IBAP. Comprehensive phytohormone profiling disclosed marked increases in indole-3-acetic acid (IAA), zeatin riboside (ZR), methyl jasmonate (JA-ME), and brassinosteroids (BRs) following XOS application. Through RNA sequencing, we identified 3807 differentially expressed genes (DEGs) in the roots of XOS-treated plants, which were significantly enriched in pathways associated with manganese ion homeostasis, microtubule motor activity, and carbohydrate metabolism. Intriguingly, approximately 62.7% of the DEGs responsive to XOS also responded to IBAP, underscoring common regulatory mechanisms. However, XOS uniquely influenced genes related to cutin, suberine, and wax biosynthesis, as well as plant hormone signal transduction, hinting at novel mechanisms of stress tolerance. Prominent up-regulation of genes encoding beta-glucosidase and beta-fructofuranosidase highlights enhanced carbohydrate metabolism as a key driver of XOS-induced root enhancement. Collectively, these results position XOS as a promising, sustainable option for agricultural biostimulation.
PubMed: 38931130
DOI: 10.3390/plants13121699 -
Molecules (Basel, Switzerland) Jun 2024In this work, we synthesized and confirmed the structure of several alkaloid N-oxides using mass spectrometry and Fourier-transform infrared spectroscopy. We also...
In this work, we synthesized and confirmed the structure of several alkaloid N-oxides using mass spectrometry and Fourier-transform infrared spectroscopy. We also investigated their reduction mechanisms using voltammetry. For the first time, we obtained alkaloid N-oxides using an oxidation reaction with potassium peroxymonosulfate as an oxidant. The structure was established based on the obtained fragmentation mass spectra recorded by LC-Q-ToF-MS. In the FT-IR spectra of the alkaloid N-oxides, characteristic signals of N-O group vibrations were recorded (bands in the range of 928 cm⁻ to 971 cm⁻), confirming the presence of this functional group. Electrochemical reduction studies demonstrated the reduction of alkaloid N-oxides at mercury-based electrodes back to the original form of the alkaloid. For the first time, the products of the electrochemical reduction of alkaloid N-oxides were detected by mass spectrometry. The findings provide insights into the structural characteristics and reduction behaviors of alkaloid N-oxides, offering implications for pharmacological and biochemical applications. This research contributes to a better understanding of alkaloid metabolism and degradation processes, with potential implications for drug development and environmental science.
Topics: Alkaloids; Oxides; Spectroscopy, Fourier Transform Infrared; Oxidation-Reduction; Electrochemical Techniques; Molecular Structure; Mass Spectrometry; Electrodes
PubMed: 38930787
DOI: 10.3390/molecules29122721 -
Foods (Basel, Switzerland) Jun 2024The instability of calcium tartrate (CaT) in wines occurs when the effective concentration of ions surpasses the solubility product, leading to the formation of CaT...
The instability of calcium tartrate (CaT) in wines occurs when the effective concentration of ions surpasses the solubility product, leading to the formation of CaT crystals. Unlike potassium hydrogen tartrate (KHT), temperature has little effect on the rate of CaT precipitation, making cold stabilization ineffective. Additives like metatartaric acid and carboxymethylcellulose (CMC) have been used to mitigate this problem, but metatartaric acid's effectiveness is limited due to hydrolysis. Additionally, potassium polyaspartate (KPA), commonly used as a KHT stabilizer, has been reported to reduce wine stability regarding CaT instability. Therefore, exploring alternative stabilization methods is crucial. Alginic acid, permitted as a processing aid in winemaking, can be an alternative to CMC and metatartaric acid due to its strong negative charge and ability to bind calcium ions. This study aimed to assess alginic acid's efficacy as a CaT stabilizer compared to CMC and investigate the impact of KPA on CaT instability. The results showed that KPA did not increase CaT instability and even improved its stability in some wines. Alginic acid outperformed both CMC and KPA in mitigating CaT instability, possibly due to its higher zeta potential and calcium ion complexation ability. This study is the first to investigate the use of alginic acid for CaT stability in wine.
PubMed: 38928821
DOI: 10.3390/foods13121880