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1.
Nano Lett ; 24(28): 8525-8534, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38954769

RESUMO

Cr2(NCN)3 is a potentially high-capacity and fast-charge Li-ion anode owing to its abundant and broad tunnels. However, high intrinsic chemical instability severely restricts its capacity output and electrochemical reversibility. Herein we report an effective crystalline engineering method for optimizing its phase and crystallinity. Systematic studies reveal the relevancy between electrochemical performance and crystalline structure; an optimal Cr2(NCN)3 with high phase purity and uniform crystallinity exhibits a high reversible capacity of 590 mAh g-1 and a stable cycling performance of 478 mAh g-1 after 500 cycles. In-operando heating XRD reveals its high thermodynamical stability over 600 °C, and in-operando electrochemical XRD proves its electrochemical Li storage mechanism, consisting of the primary Li-ion intercalation and subsequent conversion reactions. This study introduces a facile and low-cost method for fabricating high-purity Cr2(NCN)3, and it also confirms that the Li storage of Cr2(NCN)3 can be further improved by tuning its phase and crystallinity.

2.
ACS Appl Mater Interfaces ; 16(25): 32291-32297, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38872393

RESUMO

Self-healing functional materials can repair cracks and damage inside the battery, ensuring the stability of the battery material structure. This feature minimizes performance degradation during the charging and discharging processes, improving the efficiency and stability of the battery. Here, we have developed a novel healing conductive two-dimensional sulfur iodide (SI4) composite cathode. This process integrates both sulfur and iodine compounds into carbon nanocages, forming a SI4@C core-shell structure. This cathode design improves electrical conductivity and repairability, facilitates rapid activation, and ensures structural integrity, resulting in a typical Na-SI4 battery with high capacity and an exceptionally long cycle life. At 10.0 A g-1, the capacity of the Na-SI4 battery can still reach 217.4 mAh g-1 after more than 500 cycles, and the capacity decay rate per cycle is only 0.06%. In addition, the cathode exhibits a cascade redox reaction involving S and I, contributing to its high capacity. The in situ growth of a carbon shell further enhances the conductivity and structural robustness of the entire cathode. The flexibility and bendability of SI4@C-carbon cloth make it applicable for flexible electronic devices, providing more possibilities for battery design. The strategy of engineering a two-dimensional self-healing structure to construct a superior cathode is expected to be widely applied to other electrode materials. This study provides a new pathway for designing novel binary-conversion-type sodium-ion batteries with excellent long-term cycling performance.

3.
ACS Appl Mater Interfaces ; 16(23): 29793-29804, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38819663

RESUMO

The effectiveness of photodynamic therapy (PDT) in treating brain gliomas is limited by the solubility of photosensitizers and the production of reactive oxygen species (ROS), both of which are influenced by the concentration of photosensitizers and catalyst active sites. In this study, we developed a controllable surface hydroxyl concentration for the photosensitizer CN11 to address its poor water solubility issue and enhance PDT efficacy in tumor treatment. Compared to pure g-C3N4 (CN), CN11 exhibited 4.6 times higher hydrogen peroxide production under visible light, increased incidence of the n → π* electron transition, and provided more available reaction sites for cytotoxic ROS generation. These findings resulted in a 2.43-fold increase in photodynamic treatment efficacy against brain glioma cells. Furthermore, in vivo experiments conducted on mice demonstrated that CN11 could be excreted through normal cell metabolism with low cytotoxicity and high biosafety, effectively achieving complete eradication of tumor cells.


Assuntos
Neoplasias Encefálicas , Glioma , Nitrilas , Fotoquimioterapia , Fármacos Fotossensibilizantes , Glioma/tratamento farmacológico , Glioma/patologia , Glioma/metabolismo , Animais , Camundongos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Nitrilas/química , Nitrilas/farmacologia , Humanos , Espécies Reativas de Oxigênio/metabolismo
4.
Small ; : e2311650, 2024 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-38764187

RESUMO

Current lithium-ion batteries cannot meet the requirement of higher energy density with further large-scale application of electrical vehicles. Lithium metal batteries combined with Ni-rich layered oxides cathode are expected as the one of promising solutions, while the poor electrode and electrolyte interface impedes the commercial development of lithium metal batteries. A new double-salts super concentrated (DSSC) carbonate electrolyte is proposed to improve the electrochemical performance of LiNi0.90Co0.05Mn0.05O2 (NCM9055)||Li metal battery which exhibits stable cycling performance with the capacity retention of 93.04% and reversible capacity of 173.8 mAh g-1 after 100 cycles at 1 C, while cells with conventional 1 m diluted electrolyte remains only 60.55% and capacity of 114.2 mAh g-1. The double salts synergistic effect in super concentrated electrolyte promotes the formation for more balanced stable cathode electrolyte interface (CEI) inorganic compounds of CFx, LiNOx, SOF2, Li2SO4, and less LiF by X-ray photoelectron spectroscopy (XPS) test, and the uniform 2-3 nm rock-salt phase protection layer on the cathode surface by transmission electron microscope (TEM) characterization, improving the cycling performance of the Ni-rich NCM9055 layered oxide cathode. The DSSC electrolyte also can relief the Li dendrite growth on Li metal anode, as well as exhibit better flame retardance, promoting the application of more safety Ni-rich NCM9055||Li metal batteries.

5.
Front Microbiol ; 15: 1367583, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38585706

RESUMO

The development of innovative methods for highly efficient production of recombinant proteins remains a prominent focus of research in the biotechnology field, primarily due to the fact that current commercial protein expression systems rely on expensive chemical inducers, such as isopropyl ß-D-thiogalactoside (IPTG). In our study, we designed a novel approach for protein expression by creating a plasmid that responds to copper. This specialized plasmid was engineered through the fusion of a copper-sensing element with an optimized multiple cloning site (MCS) sequence. This MCS sequence can be easily customized by inserting the coding sequences of target recombinant proteins. Once the plasmid was generated, it was introduced into an engineered Escherichia coli strain lacking copA and cueO. With this modified E. coli strain, we demonstrated that the presence of copper ions can efficiently trigger the induction of recombinant protein expression, resulting in the production of active proteins. Most importantly, this expression system can directly utilize copper-containing industrial wastewater as an inducer for protein expression while simultaneously removing copper from the wastewater. Thus, this study provides a low-cost and eco-friendly strategy for the large-scale recombinant protein production. To the best of our knowledge, this is the first report on the induction of recombinant proteins using industrial wastewater.

6.
Adv Mater ; 36(2): e2304040, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37461204

RESUMO

As alternatives to batteries with organic electrolytes, aqueous zinc-based batteries (AZBs) have been intensively studied. However, the sluggish kinetics, side reactions, structural collapse, and dissolution of the cathode severely compromise the commercialization of AZBs. Among various strategies to accelerate their practical applications, multi-ion engineering shows great feasibility to maintain the original structure of the cathode and provide sufficient energy density for high-performance AZBs. Though multi-ion engineering strategies could solve most of the problems encountered by AZBs and show great potential in achieving practical AZBs, the comprehensive summaries of the batteries undergo electrochemical reactions involving more than one charge carrier is still in deficiency. The ambiguous nomenclature and classification are becoming the fountainhead of confusion and chaos. In this circumstance, this review overviews all the battery configurations and the corresponding reaction mechanisms are investigated in the multi-ion engineering of aqueous zinc-based batteries. By combing through all the reported works, this is the first to nomenclate the different configurations according to the reaction mechanisms of the additional ions, laying the foundation for future unified discussions. The performance enhancement, fundamental challenges, and future developing direction of multi-ion strategies are accordingly proposed, aiming to further accelerate the pace to achieve the commercialization of AZBs with high performance.

7.
Neural Netw ; 171: 53-60, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38091764

RESUMO

This paper presents a delay-variation-dependent approach to fault detection of a discrete-time Markov jump neural network (MJNN) with a time-varying delay and mismatched modes. The goal is to detect the potential fault of delayed MJNNs by constructing an appropriate adaptive event-triggered and asynchronous H∞ filter. By choosing a delay-product-type Lyapunov-Krasovskii (L-K) functional with a delay-dependent matrix and exploiting some matrix polynomial inequalities, bounded real lemmas (BRLs) are obtained on the existence of suitable adaptive event generator and filters. These BRLs are dependent not only on the delay bounds but also on the delay variation rate. Simulation results are given to show the validity of the proposed theoretical method.


Assuntos
Algoritmos , Redes Neurais de Computação , Fatores de Tempo , Simulação por Computador
8.
Small ; 20(5): e2306595, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37732373

RESUMO

Iron-based sulfate cathodes of alluaudite Na2+2 δ Fe2- δ (SO4 )3 (NFS) in sodium-ion batteries with low cost, steady cycling performance, and high voltage are promising for grid-scale energy storage systems. However, the poor electronic conductivity and the limited understanding of the phase-evolution of precursors hinder obtaining high-rate capacity and the pure phase. Distinctive NFS@C@n%CNTs (n = 1, 2, 5, 10) sphere-shell conductive networks composite cathode materials are constructed creatively, which exhibit superior reversible capacity and rate performance. In detail, the designed NFS@C@2%CNTs cathode delivers an initial discharge capacity of 95.9 mAh g-1 at 0.05 C and up to 60 mAh g-1 at a high rate of 10 C. The full NFS@C@2%CNTs//HC cell delivers a practical operating voltage of 3.5 V and mass-energy density of 140 Wh kg-1 at 0.1 C, and it can also retain 67.37 mAh g-1 with a capacity retention rate of 96.4% after 200 cycles at 2 C. On the other hand, a novel combination reaction mechanism is first revealed for forming NFS from the mixtures of Na2 Fe(SO4 )2 ·nH2 O (n = 2, 4) and FeSO4 ·H2 O during the sintering process. The inspiring results would provide a novel perspective to synthesize high-performance alluaudite sulfate and analogs by aqueous methods.

9.
Adv Mater ; 36(3): e2307795, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37823519

RESUMO

Efficient storage and separation of holes and electrons pose significant challenges for catalytic reactions, particularly in the context of single-phase catalysis. Herein, V2 C MXene, with its intrinsic polarized electric field, successfully overcomes this obstacle. To enhance hole storage, a multistep etching process is employed under reducing conditions to control the content of surface termination groups, thus exposing more defective active sites. The intrinsically polarized electric field confines holes to the surface of the layer and free electrons within the layer, leading to a lag in e- release compared to h+ . The quantities of stored holes and electrons are measured to be 18.13 µmol g-1 and 106.37 µmol g-1 , respectively. Under dark, V2 C demonstrates excellent and stable dark-catalytic performance, degrading 57.91% of tetracycline (TC 40 mg L-1 ) and removing 23% of total organic carbon (TOC) after 140 min. In simulated sunlight and near-infrared light, the corresponding degradation rates reach 72.24% and 79.54%, with corresponding TOC removal rates of 49% and 48%, respectively. The hole and electron induced localized surface plasmon resonance (LSPR) effects contribute to a long-lasting and enhanced broad-spectrum mineralization of V2 C MXene. This study provides valuable insights into the research and application of all-weather MXene energy storage catalytic materials.

10.
Artigo em Inglês | MEDLINE | ID: mdl-37922184

RESUMO

This brief investigates the stability problem of recurrent neural networks (RNNs) with time-varying delay. First, by introducing some flexibility factors, a flexible negative-determination quadratic function method is proposed, which contains some existing methods and has less conservatism. Second, some integral inequalities and the flexible negative-determination quadratic function method are used to give an accurate upper bound of the Lyapunov-Krasovskii functional (LKF) derivative. As a result, a less conservative stability criterion of delayed RNNs is derived, whose effectiveness and superiority are finally illustrated through two numerical examples.

11.
J Colloid Interface Sci ; 652(Pt A): 599-611, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37611469

RESUMO

Nb2AlC/Nb2C MXene (NAC/NC) heterojunction photocatalysts with Schottky junctions were obtained by selective etching of the Al layer, resulting in 146.25 µmol·g-1 electrons and 15.28 µmol·g-1 holes stored in the heterojunction. The average conversion of NAC/NC thermally coupled photocatalytic reduction of CO2 under the simulated solar irradiation reached 110.15 µmol⋅g-1⋅h-1, and the CO selectivity reached over 92%, which was 1.49 and 1.74 times higher than that of pure Nb2AlC and Nb2C MXene, respectively. After light excitation, the localized surface plasmon resonance (LSPR) effect of holes distributed on the surface of Nb2C MXene crystals in the heterojunction will form high-energy thermal holes to dissociate H2 to H+ and reduce CO2 to form H2O at the same time. The high-energy electrons formed by the LSPR effect of Nb2C MXene and the conduction band electrons generated by the photoexcitation of Nb2C MXene can be migrated to Nb2AlC under the action of the interfacial Schottky junction to supplement the electrons needed for the LSPR effect of Nb2AlC, which continuously forms high-energy hot electrons to convert the adsorbed CO2 into *CO2-, b-HCO3, and HCOO. Subsequently, HCOO releases ⋅OH in a cyclic reaction to continuously reduce to form CO. The dual LSPR effect of Nb2AlC and Nb2C MXene is used to enhance the hydrogenation activity of thermally coupled photocatalytic reduction of CO2, which provides a new research idea for the application of MXene in thermally coupled photoreduction of CO2.

12.
Small ; 19(42): e2301301, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37340577

RESUMO

High-capacity silicon has been regarded as one of the most promising anodes for high-energy lithium-ion batteries. However, it suffers from severe volume expansion, particle pulverization, and repeated solid electrolyte interphase (SEI) growth, which leads to rapid electrochemical failure, while the particle size also plays key role here and its effects remain elusive. In this paper, through multiple-physical, chemical, and synchrotron-based characterizations, the evolutions of the composition, structure, morphology, and surface chemistry of silicon anodes with the particle size ranging from 50 to 5 µm upon cycling are benchmarked, which greatly link to their electrochemical failure discrepancies. It is found that the nano- and micro-silicon anodes undergo similar crystal to amorphous phase transition, but quite different composition transition upon de-/lithiation; at the same time, the nano- and 1 µm-silicon samples present obviously different mechanochemical behaviors from the 5 µm-silicon sample, such as electrode crack, particle pulverization/crack as well as volume expansion; in addition, the micro-silicon samples possess much thinner SEI layer than the nano-silicon samples upon cycling, and also differences in SEI compositions. It is hoped this comprehensive study and understanding should offer critical insights into the exclusive and customized modification strategies to diverse silicon anodes ranging from nano to microscale.

13.
Free Radic Biol Med ; 204: 359-373, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37225108

RESUMO

Copper is an essential mineral nutrient that provides the cofactors for some key enzymes. However, excess copper is paradoxically cytotoxic. Wilson's disease is an autosomal recessive hereditary disease characterized by pathological copper accumulation in many organs, with high mortality and disability. Nevertheless, many questions about the molecular mechanism in Wilson's disease remain unknown and there is an imperative need to address these questions to better exploit therapeutic strategy. In this study, we constructed the mouse model of Wilson's disease, ATP7A-/- immortalized lymphocyte cell line and ATP7B knockdown cells to explore whether copper could impair iron-sulfur cluster biogenesis in eukaryotic mitochondria. Through a series of cellular, molecular, and pharmacological analyses, we demonstrated that copper could suppress the assembly of Fe-S cluster, decrease the activity of the Fe-S enzyme and disorder the mitochondrial function both in vivo and in vitro. Mechanistically, we found that human ISCA1, ISCA2 and ISCU proteins have a strong copper-binding activity, which would hinder the process of iron-sulfur assembly. Of note, we proposed a novel mechanism of action to explain the toxicity of copper by providing evidence that iron-sulfur cluster biogenesis may be a primary target of copper toxicity both in cells and mouse models. In summary, the current work provides an in-depth study on the mechanism of copper intoxication and describes a framework for the further understanding of impaired Fe-S assembly in the pathological processes of Wilson's diseases, which helps to develop latent therapeutic strategies for the management of copper toxicity.


Assuntos
Degeneração Hepatolenticular , Proteínas Ferro-Enxofre , Animais , Humanos , Camundongos , Cobre/metabolismo , Cobre/toxicidade , Degeneração Hepatolenticular/tratamento farmacológico , Degeneração Hepatolenticular/genética , Ferro/metabolismo , Proteínas Ferro-Enxofre/genética , Proteínas Ferro-Enxofre/metabolismo , Proteínas Mitocondriais/metabolismo , Enxofre/metabolismo
14.
Front Microbiol ; 14: 1084205, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36876095

RESUMO

Escherichia coli cysteine desulfurase (CD), IscS, modifies basal metabolism by transferring sulphur (S) from L-cysteine to numerous cellular pathways, whereas NFS1, a human CD, is active only in the formation of the [Acp]2:[ISD11]2:[NFS1]2 complex. Despite the accumulation of red-coloured IscS in E. coli cells as a result of the deficiency of accessible iron, as revealed in our previous studies, the mechanism of the potential enzymatic reaction remains unclear. In this study, the N-terminus of IscS was fused with the C-terminus of NFS1, which was reported to be almost fully active as IscS and exhibits a pyridoxal 5'-phosphate (PLP) absorption peak at 395 nm. Moreover, SUMO-EH-IscS exhibited significant growth recovery and NADH-dehydrogenase I activity in the iscS mutant cells. Furthermore, through in vitro and in vivo experiments combined with high-performance liquid chromatography and ultra-performance liquid chromatography-tandem mass spectrometry, it was shown that the new absorption peaks of the IscS H104Q, IscS Q183E, IscS K206A, and IscS K206A&C328S variants at 340 and 350 nm may correspond to the enzyme reaction intermediates, Cys-ketimine and Cys-aldimine, respectively. However, after mutation of the conserved active-site residues, additional absorption peaks at 420 and 430 nm were associated with PLP migration in the active-site pocket. Additionally, the corresponding absorption peaks of Cys-quinonoid, Ala-ketimine, and Ala-aldimine intermediates in IscS were 510, 325, and 345 nm, respectively, as determined by site-directed mutagenesis and substrate/product-binding analyses during the CD reaction process. Notably, red IscS formed in vitro by incubating IscS variants (Q183E and K206A) with excess L-alanine and sulphide under aerobic conditions produced an absorption peak similar to the wild-type IscS, at 510 nm. Interestingly, site-directed mutation of IscS with hydrogen bonds to PLP at Asp180 and Gln183 resulted in a loss of enzymatic activity followed by an absorption peak consistent with NFS1 (420 nm). Furthermore, mutations at Asp180 or Lys206 inhibited the reaction of IscS in vitro with L-cysteine (substrate) and L-alanine (product). These results suggest that the conserved active site residues (His104, Asp180, and Gln183) and their hydrogen bond with PLP in the N-terminus of IscS play a key role in determining whether the L-cysteine substrate can enter the active-site pocket and regulate the enzymatic reaction process. Therefore, our findings provide a framework for evaluating the roles of conserved active-site residues, motifs, and domains in CDs.

15.
Nano Lett ; 23(5): 1743-1751, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36811529

RESUMO

P2-Na0.67Ni0.33Mn0.67O2 represents a promising cathode for Na-ion batteries, but it suffers from severe structural degradation upon storing in a humid atmosphere and cycling at a high cutoff voltage. Here we propose an in situ construction to achieve simultaneous material synthesis and Mg/Sn cosubstitution of Na0.67Ni0.33Mn0.67O2 via one-pot solid-state sintering. The materials exhibit superior structural reversibility and moisture insensitivity. In-operando XRD reveals an essential correlation between cycling stability and phase reversibility, whereas Mg substitution suppressed the P2-O2 phase transition by forming a new Z phase, and Mg/Sn cosubstitution enhanced the P2-Z transition reversibility benefiting from strong Sn-O bonds. DFT calculations disclosed high chemical tolerance to moisture, as the adsorption energy to H2O was lower than that of the pure Na0.67Ni0.33Mn0.67O2. A representative Na0.67Ni0.23Mg0.1Mn0.65Sn0.02O2 cathode exhibits high reversible capacities of 123 mAh g-1 (10 mA g-1), 110 mAh g-1 (200 mA g-1), and 100 mAh g-1 (500 mA g-1) and a high capacity retention of 80% (500 mA g-1, 500 cycles).

16.
IEEE Trans Neural Netw Learn Syst ; 34(2): 1074-1079, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34424846

RESUMO

This brief investigates the problem of state estimation of quaternion-valued neural networks (QVNNs) with time-varying delays. First, by extending the Jensen inequality to quaternion domain, an extended Jensen inequality with quaternion term is derived. Second, a class of proportional-integral state estimator (PISE) with exponential decay term is proposed. Then, by constructing a suitable Lyapunov-Krasovskii functional (LKF), some sufficient conditions are obtained to ensure the existence of the designed PISE and the gain matrices of the designed PISE can be directly computed. Simulations are given to illustrate the advantage of the proposed method.

17.
Small Methods ; 6(11): e2200995, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36250994

RESUMO

It is a major challenge to achieve a high-performance anode for sodium-ion batteries (SIBs) with high specific capacity, high rate capability, and cycling stability. Bismuth sulfide, which features a high theoretical specific capacity, tailorable morphology, and low cost, has been considered as a promising anode for SIBs. Nevertheless, due to a lack of direct atomistic observation, the detailed understanding of fundamental intercalation behavior and Bi2 S3 's (de)sodiation mechanisms remains unclear. Here, by employing in situ high-resolution transmission electron microscopy, consecutive electron diffraction coupled with theoretical calculations, it is not only for the first time identified that Bi2 S3 exhibits specific ionic transport pathways preferred to diffuse along the (110) direction instead of the (200) plane, but also tracks their real-time phase transformations (de)sodiation involving multi-step crystallographic tuning. The finite-element analysis further disclosed multi-reaction induced deformation and the relevant stress evolution originating from the combined effect of the mechanical and electrochemical interaction. These discoveries not only deepen the understanding of fundamental science about the microscopic reaction mechanism of metal chalcogenide anodes but also provide important implications for performance optimization.

18.
Small Methods ; 6(9): e2200555, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35780504

RESUMO

The development of large-scale energy storage systems (EESs) is pivotal for applying intermittent renewable energy sources such as solar energy and wind energy. Lithium-ion batteries with LiFePO4 cathode have been explored in the integrated wind and solar power EESs, due to their long cycle life, safety, and low cost of Fe. Considering the penurious reserve and regional distribution of lithium resources, the Fe-based sodium-ion battery cathodes with earth-abundant elements, environmental friendliness, and safety appear to be the better substitutes in impending grid-scale energy storage. Compared to the transition metal oxide and Prussian blue analogs, the Fe-based polyanionic oxide cathodes possess high thermal stability, ultra-long cycle life, and adjustable voltage, which is more commercially viable in the future. This review summarizes the research progress of single Fe-based polyanionic and mixed polyanionic oxide cathodes for the potential sodium-ion batteries EESs candidates. In detail, the synthesized method, crystal structure, electrochemical properties, bottlenecks, and optimization method of Fe-based polyanionic oxide cathodes are discussed systematically. The insights presented in this review may serve as a guideline for designing and optimizing Fe-based polyanionic oxide cathodes for coming commercial sodium-ion batteries EESs.

19.
Nano Lett ; 22(13): 5221-5229, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35727314

RESUMO

Enhancing microstructural and electrochemical stabilities of Ni-rich layered oxides is critical for improving the safety and cycle-life of high-energy Li-ion batteries. Here we propose a thermochemical cyclization strategy where heating polyacrylonitrile with LiNi0.8Co0.1Mn0.1O2 can simultaneously construct a cyclized polyacrylonitrile outer layer and a rock-salt bridge-like inner layer, forming a compact dual-coating of LiNi0.8Co0.1Mn0.1O2. Systematic studies demonstrate that the mild cyclization reaction between polyacrylonitrile and LiNi0.8Co0.1Mn0.1O2 induces a desirable "layered to rock-salt" structural transformation to create a nano-intermedium that acts as the bridge for binding cyclized polyacrylonitrile to layered LiNi0.8Co0.1Mn0.1O2. Because of the improvement of the structural and electrochemical stability and electrical properties, this cathode design remarkably enhances the cycling performance and rate capability of LiNi0.8Co0.1Mn0.1O2, showing a high reversible capacity of 183 mAh g-1 and a high capacity retention of 83% after 300 cycles at 1 C rate. Notably, this facile and scalable surface engineering makes Ni-rich cathodes potentially viable for commercialization in high-energy Li-ion batteries.

20.
Biochim Biophys Acta Mol Cell Res ; 1869(10): 119307, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35714932

RESUMO

Iron­sulfur (Fe-S) clusters have been shown to play important roles in various cellular physiological process. Iron­sulfur cluster assembly 2 (ISCA2) is a vital component of the [4Fe-4S] cluster assembly machine. Several studies have shown that ISCA2 is highly expressed during erythroid differentiation. However, the role and specific regulatory mechanisms of ISCA2 in erythroid differentiation and erythroid cell growth remain unclear. RNA interference was used to deplete ISCA2 expression in human erythroid leukemia K562 cells. The proliferation, apoptosis, and erythroid differentiation ability of the cells were assessed. We show that knockdown of ISCA2 has profound effects on [4Fe-4S] cluster formation, diminishing mitochondrial respiratory chain complexes, leading to reactive oxygen species (ROS) accumulation and mitochondrial damage, inhibiting cell proliferation. Excessive ROS can inhibit the activity of cytoplasmic aconitase (ACO1) and promote ACO1, a bifunctional protein, to perform its iron-regulating protein 1(IRP1) function, thus inhibiting the expression of 5'-aminolevulinate synthase 2 (ALAS2), which is a key enzyme in heme synthesis. Deficiency of ISCA2 results in the accumulation of iron divalent. In addition, the combination of excessive ferrous iron and ROS may lead to damage of the ACO1 cluster and higher IRP1 function. In brief, ISCA2 deficiency inhibits heme synthesis and erythroid differentiation by double indirect downregulation of ALAS2 expression. We conclude that ISCA2 is essential for normal functioning of mitochondria, and is necessary for erythroid differentiation and cell proliferation.


Assuntos
Proteína 1 Reguladora do Ferro/metabolismo , Proteínas Ferro-Enxofre/metabolismo , 5-Aminolevulinato Sintetase/metabolismo , Aconitato Hidratase/genética , Heme/metabolismo , Humanos , Ferro/metabolismo , Proteínas Ferro-Enxofre/genética , Células K562 , Espécies Reativas de Oxigênio/metabolismo , Enxofre/metabolismo
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