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1.
Chem Commun (Camb) ; 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39086195

RESUMO

The practical application of lithium metal batteries (LMBs) is inevitably associated with serious safety risks due to the uncontrolled growth of lithium dendrites. Thus, to inhibit the formation of lithium dendrites, many researchers have focused on constructing three-dimensional porous current collectors with a high specific surface area. However, the homogeneous structure of porous collectors does not effectively guide the deposition of lithium metal to the bottom, leading to a phenomenon known as "top-growth." Recently, the construction of 3D porous current collectors with a lithiophilic gradient has been widely reported and regarded as an effective approach to inhibit lithium top-growth, thus improving battery safety. In this review, we summarize the latest research progress on such anode current collector design strategies, including surface modification of different base materials, design of gradient structures, and field factors, emphasizing their lithium-affinity mechanism and the advantages and disadvantages of different collector designs. Finally, we provide a perspective on the future research directions and applications of gradient affinity current collectors.

2.
Artigo em Inglês | MEDLINE | ID: mdl-39096487

RESUMO

Vanadium pentoxide (V2O5) is considered a promising material for electrochromic supercapacitors due to its rich color transitions and excellent electrochemical capacity. However, V2O5 exhibits low electrical conductivity, and its volume changes dramatically during charge-discharge cycles, leading to structural collapse and poor long-term cyclability. These issues have hindered the development and application of V2O5. In this study, copper vanadium oxide yolk-shell microspheres (CVO) were synthesized through a one-step solvent heat treatment with an annealing process. With the doping of copper element, the capacitance, conductivity, and cyclic stability of CVO microspheres were significantly enhanced. Subsequently, the sphere-wire network structure was formed by blending Na2V6O16·3H2O nanowires (NVO), resulting in the formation of CVO/NVO composites. The three-dimensional sphere-wire network efficiently facilitates the acquisition of additional redox sites and strengthens the material-to-substrate bonding. Under the combined influence of these favorable factors, CVO/NVO achieved a high specific capacitance of 39.2 mF cm-2, with a capacitance retention of 84% after 7500 cycles at a current density of 0.7 mA cm-2. The fully inorganic solid-state electrochromic supercapacitor (ECSC), assembled on the basis of CVO/NVO, demonstrates a vivid and clearly distinguishable color change (ΔE* = 37). Even more impressive is the energy storage capacity (18.4 mF·cm-2) and the cycling stability (up to 89% retention after 10,000 cycles) exhibited by the devices. These key performances are superior to those of most of the previously reported V2O5-based ECSCs, opening a promising avenue for the development of V2O5-based electrochromic energy storage devices.

3.
Angew Chem Int Ed Engl ; : e202411255, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980971

RESUMO

Conversion-type electrode materials have gained massive research attention in sodium-ion batteries (SIBs), but their limited reversibility hampers practical use. Herein, we report a bifunctional nanoreactor to boost highly reversible sodium-ion storage, wherein a record-high reversible degree of 85.65% is achieved for MoS2 anodes. Composed of nitrogen-doped carbon-supported single atom Mn (NC-SAMn), this bifunctional nanoreactor concurrently confines active materials spatially and catalyzes reaction kinetics. In-situ/ex-situ characterizations including spectroscopy, microscopy, and electrochemistry, combined with theoretical simulations containing density functional theory and molecular dynamics, confirm that the NC-SAMn nanoreactors facilitate the electron/ion transfer, promote the distribution and interconnection of discharging products (Na2S/Mo), and reduce the Na2S decomposition barrier.As a result, the nanoreactor-promoted MoS2 anodes exhibit ultra-stable cycling with a capacity retention of 99.86% after 200 cycles in the full cell. This work demonstrates the superiority of bifunctional nanoreactors with two-dimensional confined and catalytic effects, providing a feasible approach to improve the reversibility for a wide range of conversion-type electrode materials, thereby enhancing the application potential for long-cycled SIBs.

4.
Artigo em Chinês | MEDLINE | ID: mdl-38973031

RESUMO

Objective:To evaluate the effects of cochlear implantation in patients with single-sided deafness(SSD) and asymmetrical hearing loss(AHL). Methods:Seventeen Mandarin-speaking CI patients diagnosed as SSD/AHL were recruited in our study. The Tinnitus Handicap Inventory(THI) and the Visual Analogue Scale(VAS) were used to assess changes in tinnitus distress and tinnitus loudness in SSD patients at each time point(pre-operation and post-operation). Results:The THI score and all 3 dimensions were significant decreased with CI-on than pre-operation(P<0.05). Tinnitus VAS scores were also decreased, and VAS scores were lower with CI-on than with CI-off, and were both significantly different at each time point after CI switch-on(P<0.05). Conclusion:CI could help SSD/AHL patients to suppress tinnitus and reduce the loudness of tinnitus. However, CI should not be a treatment of tinnitus.


Assuntos
Implante Coclear , Perda Auditiva Unilateral , Zumbido , Humanos , Implante Coclear/métodos , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Resultado do Tratamento , Implantes Cocleares , Idoso , Perda Auditiva
5.
Artigo em Chinês | MEDLINE | ID: mdl-38973051

RESUMO

With the development of social economic and technology, Cochlear Implantation has became an effective therapy for patients who suffered from severe or profound hearing impairment. In the meantime, patients' demands for sound and auditory quality are also increasing. In terms of speech recognition, localization, and auditory quality, bilateral hearing is closer to the auditory experience of normal individuals, so bilateral cochlear implantation(BCI) emerged as the times require. In this article, we will introduce the status and progress of bimodal regarding to the following aspects: the brief history, the advantages of BCI, different methods for BCI, and the problems encountered in BCI.


Assuntos
Implante Coclear , Implantes Cocleares , Humanos , Implante Coclear/métodos , Percepção da Fala , Perda Auditiva/cirurgia
6.
Mol Cancer ; 23(1): 137, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38970074

RESUMO

BACKGROUND: The outcome of hepatocellular carcinoma (HCC) is limited by its complex molecular characteristics and changeable tumor microenvironment (TME). Here we focused on elucidating the functional consequences of Maternal embryonic leucine zipper kinase (MELK) in the tumorigenesis, progression and metastasis of HCC, and exploring the effect of MELK on immune cell regulation in the TME, meanwhile clarifying the corresponding signaling networks. METHODS: Bioinformatic analysis was used to validate the prognostic value of MELK for HCC. Murine xenograft assays and HCC lung metastasis mouse model confirmed the role of MELK in tumorigenesis and metastasis in HCC. Luciferase assays, RNA sequencing, immunopurification-mass spectrometry (IP-MS) and coimmunoprecipitation (CoIP) were applied to explore the upstream regulators, downstream essential molecules and corresponding mechanisms of MELK in HCC. RESULTS: We confirmed MELK to be a reliable prognostic factor of HCC and identified MELK as an effective candidate in facilitating the tumorigenesis, progression, and metastasis of HCC; the effects of MELK depended on the targeted regulation of the upstream factor miR-505-3p and interaction with STAT3, which induced STAT3 phosphorylation and increased the expression of its target gene CCL2 in HCC. In addition, we confirmed that tumor cell-intrinsic MELK inhibition is beneficial in stimulating M1 macrophage polarization, hindering M2 macrophage polarization and inducing CD8 + T-cell recruitment, which are dependent on the alteration of CCL2 expression. Importantly, MELK inhibition amplified RT-related immune effects, thereby synergizing with RT to exert substantial antitumor effects. OTS167, an inhibitor of MELK, was also proven to effectively impair the growth and progression of HCC and exert a superior antitumor effect in combination with radiotherapy (RT). CONCLUSIONS: Altogether, our findings highlight the functional role of MELK as a promising target in molecular therapy and in the combination of RT therapy to improve antitumor effect for HCC.


Assuntos
Carcinoma Hepatocelular , Quimiocina CCL2 , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas , Proteínas Serina-Treonina Quinases , Microambiente Tumoral , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/radioterapia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/radioterapia , Humanos , Animais , Camundongos , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Quimiocina CCL2/metabolismo , Linhagem Celular Tumoral , Tolerância a Radiação , Prognóstico , Fator de Transcrição STAT3/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , MicroRNAs/genética
7.
Heliyon ; 10(12): e32782, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38975204

RESUMO

Purpose: The intimate connection between long noncoding RNA (lncRNA) and autophagy has been established in cartilage degeneration. However, their roles in meniscal degeneration remain ambiguous. This study aimed to identify the key autophagy-related lncRNA and its associated regulatory network in meniscal degeneration in the context of osteoarthritis (OA). Methods: RNA sequencing was performed to identify differentially expressed lncRNAs (DELs) and mRNAs (DEMs), which were then conducted to enrichment analyses using the DAVID database and Metascape. Autophagy-related DEMs were identified by combining DEMs with data from the Human Autophagy Database. Three databases were used to predict miRNA, and the DIANA LncBase Predicted database was utilized to predict miRNA-lncRNA interactions. Based on these predictions, comprehensive competitive endogenous RNA (ceRNA) network were constructed. The expression levels of the classical autophagy markers and autophagy-related ceRNA network were validated. Additionally, Gene Set Enrichment Analysis (GSEA) was performed using autophagy-related DEMs. Results: 310 DELs and 320 DEMs were identified, with five upregulated and one downregulated autophagy-related DEMs. Through reverse prediction of miRNA, paired miRNA-lncRNA interactions, and verification using RT-qPCR, two lncRNAs (PCAT19, CLIP1-AS1), two miRNA (has-miR-3680-3p and has-miR-4795-3p) and two mRNAs (BAG3 and HSP90AB1) were included in the constructed ceRNA regulatory networks. GSEA indicated that the increased expression of autophagy-related mRNAs inhibited glycosaminoglycan biosynthesis in the degenerative meniscus. Conclusion: This study presented the first construction of regulatory ceRNA network involving autophagy-related lncRNA-miRNA-mRNA interactions in OA meniscus. These findings offered valuable insights into the mechanisms underlying meniscal degeneration and provided potential targets for therapeutic intervention.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38977476

RESUMO

OBJECTIVE: The aim of this study was to conduct a bibliometric and visualization analysis of research on cochlear implantation (CI) for inner ear malformations (IEMs) from 1986 to 2024. METHODS: A comprehensive literature search was performed using the Web of Science Core Collection Database, resulting in the identification of 431 relevant publications. Various data analysis and visualization tools, including VOSviewer, CiteSpace, and Bibliometrix, were utilized to analyze annual publication outputs, countries/regions and institutions, authors, journals and studies, keywords, and theme evolution. RESULTS: The study revealed an overall increasing trend in research output on CI for IEMs, with significant contributions from countries such as the United States, China, Turkey, Germany, and Italy. The analysis also identified key authors, research teams, journals, and studies that have made substantial contributions to the field. Furthermore, the study highlighted important research hotspots and trends, such as the classification of IEMs, outcomes of CI for IEMs, and the management of pediatric patients with IEMs. CONCLUSION: The findings of this study provide a comprehensive overview of the research landscape surrounding CI for IEMs. The results serve as a basis for future research topic selection and emphasize the need for enhanced international collaboration and the publication of high-impact research to further advance this field.

9.
J Am Chem Soc ; 146(30): 20814-20822, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39031086

RESUMO

The sluggish CO2 reduction and evolution reaction kinetics are thorny problems for developing high-performance Li-CO2 batteries. For the complicated multiphase reactions and multielectron transfer processes in Li-CO2 batteries, exploring efficient cathode catalysts and understanding the interplay between structure and activity are crucial to couple with these pendent challenges. In this work, we applied the CoS as a model catalyst and adjusted its electronic structure by introducing sulfur vacancies to optimize the d-band and p-band centers, which steer the orbital hybridization and boost the redox kinetics between Li and CO2, thus improving the discharge platform of Li-CO2 batteries and altering the deposition behavior of discharge products. As a result, a highly efficient bidirectional catalyst exhibits an ultrasmall overpotential of 0.62 V and a high energy efficiency of 82.8% and circulates stably for nearly 600 h. Meanwhile, density functional theory calculations and multiphysics simulations further elucidate the mechanism of bidirectional activity. This work not only provides a proof of concept to design a remarkably efficient catalyst but also sheds light on promoting the reversible Li-CO2 reaction by tailoring the electronic structure.

10.
Redox Biol ; 75: 103287, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39079388

RESUMO

Hepatic ischemia/reperfusion (I/R) injury is an important cause of liver function impairment following liver surgery. The ubiquitin-proteasome system (UPS) plays a crucial role in protein quality control and has substantial impact on the hepatic I/R process. Although OTU deubiquitinase 1 (OTUD1) is involved in diverse biological processes, its specific functional implications in hepatic I/R are not yet fully understood. This study demonstrates that OTUD1 alleviates oxidative stress, apoptosis, and inflammation induced by hepatic I/R injury. Mechanistically, OTUD1 deubiquitinates and activates nuclear factor erythroid 2-related factor 2 (NRF2) through its catalytic site cysteine 320 residue and ETGE motif, thereby attenuating hepatic I/R injury. Additionally, administration of a short peptide containing the ETGE motif significantly mitigates hepatic I/R injury in mice. Overall, our study elucidates the mechanism and role of OTUD1 in ameliorating hepatic I/R injury, providing a theoretical basis for potential treatment using ETGE-peptide.

11.
Blood Sci ; 6(3): e00195, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38854482
12.
PLoS One ; 19(6): e0304052, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38913628

RESUMO

A diaphragm pump is a type of volumetric pump that has excellent sealing performance. An electromagnetic diaphragm pump is a kind of widely adopted diaphragm pump that has a simple structure, low power loss, and high cost performance. However, the calculation method of deformation for the electromagnetic diaphragm pump rubber diaphragm is presently lacking. Herein, a calculating method of deformation for the electromagnetic diaphragm pump rubber diaphragm is proposed. By establishing and analyzing a deformation model of the electromagnetic diaphragm pump rubber diaphragm, a theoretical relationship between the deformation of the electromagnetic diaphragm pump rubber diaphragm, the size of the electromagnetic diaphragm pump rubber diaphragm and the pressure of fluid is determined. The experimental results indicate that the biggest difference between the tested axial deformation and the calculated axial deformation of the electromagnetic diaphragm pump rubber diaphragm is 0.04 mm and the calculation results show agreement with the experimental results.


Assuntos
Fenômenos Eletromagnéticos , Borracha , Borracha/química , Desenho de Equipamento , Modelos Teóricos
13.
Artigo em Inglês | MEDLINE | ID: mdl-38943520

RESUMO

Sida rhombifolia (S. rhombifolia) is a widely used herbal plant for humans because of its antioxidant and antibacterial effects, but its potential use as a feed additive for livestock has not been investigated. Twenty 350 days-old Anyi tile-like grey chickens were randomly divided into a control group (fed basal diet) and a treatment group (fed basal diet + 3% of S. rhombifolia), and these chickens were feed for 31 days. Dietary S. rhombifolia remarkably enhanced plasma antioxidants, including the significantly increased total antioxidant capability (p < 0.01), catalase (p = 0.04), and superoxide dismutase (p < 0.01) in the treatment group. Furthermore, dietary S. rhombifolia also modulated chicken cecal microbiota, including an increased microbial diversity (Shannon, p = 0.03; Chao1, p = 0.03) in the treatment group. Regarding taxonomic analysis, 34 microbial taxa showed significant differences between the two groups. Meanwhile, the dominant phylum Actinobacteriota (p = 0.04), and dominant genera Desulfovibrio (p = 0.04) and Olsenella (p = 0.02) were significantly increased after treatment, whereas the pathogenic genus Escherichia-Shigella (p = 0.04) was significantly decreased after feeding S. rhombifolia. The results indicating that S. rhombifolia has potential for use as a natural plant feed additive for chickens.

14.
Biomed Chromatogr ; : e5902, 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38922974

RESUMO

Xiakucao Oral Liquid (XKCOL) has been widely used for treating mammary gland hyperplasia and goiter in China. However, its pharmacokinetic data have been missing to date. To conduct its pharmacokinetic study, we established an LC-tandem mass spectrometry method for the simultaneous determination of eight XKCOL-related compounds in rat plasma. Liquid-liquid extraction was used for the sampling process. Chromatographic separation was performed on a Phenomenon Luna C18 column with a mobile phase of methanol and 2 mM ammonium acetate, using gradient elution at a flow rate of 0.8 mL/min. Detection was performed in the multiple reaction monitoring mode using negative electrospray ionization (ESI-) with optimized MS parameters. Endogenous substances and carryover did not interfere in the detection of analytes. The calibration curves showed a good linear relationship within the linear ranges. The intra- and inter-batch accuracy and precision were 94.8%-110.0% and ≤11.2%, respectively. There was no significant matrix effect and the recovery was reproducible. The dilution of samples did not affect the accuracy and precision. The solution and plasma samples were stable under the various test conditions. The major components of XKCOL absorbed into the blood were salvianic acid A and rosmarinic acid. They demonstrated linear kinetics over the dose range used in this study.

15.
J Integr Plant Biol ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38923382

RESUMO

Rice stripe mosaic virus (RSMV) is an emerging pathogen which significantly reduces rice yields in the southern region of China. It is transmitted by the leafhopper Recilia dorsalis, which overwinters in rice fields. Our field investigations revealed that RSMV infection causes delayed rice heading, resulting in a large number of green diseased plants remaining in winter rice fields. This creates a favorable environment for leafhoppers and viruses to overwinter, potentially contributing to the rapid spread and epidemic of the disease. Next, we explored the mechanism by which RSMV manipulates the developmental processes of the rice plant. A rice heading-related E3 ubiquitin ligase, Heading date Associated Factor 1 (HAF1), was found to be hijacked by the RSMV-encoded P6. The impairment of HAF1 function affects the ubiquitination and degradation of downstream proteins, HEADING DATE 1 and EARLY FLOWERING3, leading to a delay in rice heading. Our results provide new insights into the development regulation-based molecular interactions between virus and plant, and highlights the importance of understanding virus-vector-plant tripartite interactions for effective disease management strategies.

16.
Artigo em Inglês | MEDLINE | ID: mdl-38867107

RESUMO

PURPOSE: Fluorescence imaging-guided surgery has been used in oncology. However, for tiny tumors, the current imaging probes are still difficult to achieve high-contrast imaging, leading to incomplete resection. In this study, we achieved precise surgical resection of tiny metastatic cancers by constructing an engineering erythrocyte membrane-camouflaged bioprobe (AR-M@HMSN@P). METHODS: AR-M@HMSN@P combined the properties of aggregation-induced emission luminogens (AIEgens) named PF3-PPh3 (P), with functional erythrocyte membrane modified by a modular peptide (AR). Interestingly, AR was composed of an asymmetric tripodal pentapeptide scaffold (GGKGG) with three appended modulars: KPSSPPEE (A6) peptide, RRRR (R4) peptide and cholesterol. To verify the specificity of the probe in vitro, SKOV3 cells with overexpression of CD44 were used as the positive group, and HLF cells with low expression of CD44 were devoted as the control group. The AR-M@HMSN@P fluorescence imaging was utilized to provide surgical guidance for the removal of micro-metastatic lesions. RESULTS: In vivo, the clearance of AR-M@HMSN@P by the immune system was reduced due to the natural properties inherited from erythrocytes. Meanwhile, the A6 peptide on AR-M@HMSN@P was able to specifically target CD44 on ovarian cancer cells, and the electrostatic attraction between the R4 peptide and the cell membrane enhanced the firmness of this targeting. Benefiting from these multiple effects, AR-M@HMSN@P achieved ultra-precise tumor imaging with a signal-to-noise ratio (SNR) of 15.2, making it possible to surgical resection of tumors < 1 mm by imaging guidance. CONCLUSION: We have successfully designed an engineered fluorescent imaging bioprobe (AR-M@HMSN@P), which can target CD44-overexpressing ovarian cancers for precise imaging and guide the resection of minor tumors. Notably, this work holds significant promise for developing biomimetic probes for clinical imaging-guided precision cancer surgery by exploiting their externally specified functional modifications.

17.
Infect Drug Resist ; 17: 1869-1877, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38745679

RESUMO

Chronic Mucocutaneous Candidiasis (CMC) is a rare immunodeficiency disease characterized by chronic or recurrent superficial Candida infections on the skin, nail, and mucous membranes. Here, we present four Chinese patients with CMC who manifested oral mucosal leukoplakia and nail thickening during early childhood, all displaying fissured tongue lines. The causative pathogens isolated from their oral mucosa and nails were identified as C. albicans and C. parapsilosis through morphology and molecular sequencing. Notably, among the four patients, one presented with vitiligo, while another had hypothyroidism. We have also conducted a review of reported cases of CMC in China and worldwide over the last five years, highlighting potential approaches for diagnosis and treatment. The current molecular evidence in the literature suggests potential for the development of early diagnosis methods, such as screening genetic variables on STAT1 and STAT3. Additionally, potential treatment avenues, including gene-targeted analogues and GM-CSF analogues, could be explored in conjunction with traditional antifungal therapy.

18.
J Gastrointest Oncol ; 15(2): 597-611, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38756631

RESUMO

Background: As one of the most common diseases in terms of cancer-related mortality worldwide, gastric adenocarcinoma (GA) frequently develops peritoneal metastases (PMs) in advanced stages. Systemic therapy or optimal supportive care are recommended for advanced GA; however, patients frequently develop drug resistance. Surgical resection is not recommended for stage IV patients, and there have been some controversies regarding the role of it in GA patients with PMs. The aim of the study was to preliminarily evaluate the possible effect of surgical treatments on patients with only PMs from GA. Methods: Data were collected from the Surveillance, Epidemiology and End Results (SEER) database (year 2000-2022). A propensity score matching (PSM) was performed to reduce the influence of selection bias and confounding variables on comparisons. Then Cox proportional hazard regression, Kaplan-Meier analysis, and log-rank test were performed to assess the efficacy of surgical treatment in patients with PMs from GA. Results: A total of 399 patients diagnosed with PMs from GA were enrolled for our analysis, of which, 180 (45.1%) patients did not receive surgery and 219 (54.9%) patients received surgery. Multivariate Cox regression analysis before PSM indicated higher rates of overall survival (OS) outcome for patients who had received surgery [hazard ratio (HR) =0.4342, 95% confidence interval (CI): 0.3283-0.5742, P<0.001]. After PSM, a total of 172 patients were enrolled, with 86 in each group. Multivariate Cox analysis showed that surgery was the independent factor reflecting patients' survival (HR =0.4382, 95% CI: 0.3037-0.6324, P<0.001). Subgroup survival analysis revealed that surgery may bring advantages to patients with grades I-IV, stages T1-T4, stage N0, and tumor size less than 71 mm (P<0.05). We also found that the OS of chemotherapy patients who had undergone surgery was better than that of chemotherapy patients who had not undergone surgery (P<0.01). Conclusions: Based on the SEER database, surgery has better OS for patients only with PMs from GA. Patients without lymph node metastasis and those who received chemotherapy before may benefit from surgery. These specific groups of patients may have surgery as an option to improve the prognosis.

19.
Sci Rep ; 14(1): 10464, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714792

RESUMO

In order to investigate the failure modes and instability mechanism of fractured rock. Uniaxial compression tests were conducted on sandstone specimens with different dip angles. Based on rock energy dissipation theory and fractal theory, the energy evolution characteristics and fragmentation fractal characteristics in the process of deformation and failure of specimens were analyzed. The results show that the peak strength and elastic modulus of fractured rock mass are lower than those of intact samples, and both show an exponential increase with the increase of fracture dip angle. The energy evolution laws of different fracture specimens are roughly similar and can be classified into four stages based on the stress-strain curve: pressure-tight, elastic, plastic, and post-destructive. The total strain energy, elastic strain energy, and dissipated strain energy of the specimen at the peak stress point increased exponentially with crack inclination, and the dissipated strain energy and compressive strength conformed to a power function growth relationship. The distribution of the fragments after the failure of the fracture sample has fractal characteristics, and the fractal dimension increases with the increase of the fracture dip angle. In addition, the higher the compressive strength of the specimen, the greater the energy dissipation, the more serious the degree of fragmentation, and the greater the fractal dimension. The data fitting further shows that there is a power function relationship between the dissipated strain energy and the fractal dimension. The research results can provide a theoretical basis for the stability of rock mass engineering and structural deformation control.

20.
Small ; : e2401100, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38721947

RESUMO

The increasing need for energy storage devices with high energy density has led to significant interest in Li-metal batteries (LMBs). However, the use of commercial electrolytes in LMBs is problematic due to their flammability, inadequate performance at low temperatures, and tendency to promote the growth of lithium dendrites and other flaws. This study introduces a localized high-concentration electrolyte (LHCE) that addresses these issues by employing non-flammable electrolyte components and incorporating carefully designed additives to enhance flame retardancy and low-temperature performance. By incorporating additives to optimize the electrolyte, it is possible to attain inorganic-dominated solid electrolyte interphases on both the cathode and anode. This achievement results in a uniform deposition of lithium, as well as the suppression of electrolyte decomposition and cathode deterioration. Consequently, this LHCE achieve over 300 stable cycles for both LiNi0.9Mn0.05Co0.05O2||Li cells and LiCoO2||Li cells, as well as 50 cycles for LiNi0.8Mn0.1Co0.1O2 (NCM811||Li) pouch cells. Furthermore, NCM811||Li cells maintain 84% discharge capacity at -20 °C, in comparison to the capacity at room temperature. The utilization of this electrolyte presents novel perspectives for the safe implementation of LMBs.

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