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1.
Sci Rep ; 14(1): 964, 2024 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-38200058

RESUMO

Immunotherapy has emerged as a promising modality for addressing advanced or conventionally drug-resistant malignancies. When it comes to lung adenocarcinoma (LUAD), T cells have demonstrated significant influence on both antitumor activity and the tumor microenvironment. However, their specific contributions remain largely unexplored. This investigation aimed to delineate molecular subtypes and prognostic indicators founded on T cell marker genes, thereby shedding light on the significance of T cells in LUAD prognosis and precision treatment. The cellular phenotypes were identified by scrutinizing the single-cell data obtained from the GEO repository. Subsequently, T cell marker genes derived from single-cell sequencing analyses were integrated with differentially expressed genes from the TCGA repository to pinpoint T cell-associated genes. Utilizing Cox analysis, molecular subtypes and prognostic signatures were established and subsequently verified using the GEO dataset. The ensuing molecular and immunological distinctions, along with therapy sensitivity between the two sub-cohorts, were examined via the ESTIMATE, CIBERSORT, and ssGSEA methodologies. Compartmentalization, somatic mutation, nomogram development, chemotherapy sensitivity prediction, and potential drug prediction analyses were also conducted according to the risk signature. Additionally, real-time qPCR and the HPA database corroborated the mRNA and protein expression patterns of signature genes in LUAD tissues. In summary, this research yielded an innovative T cell marker gene-based signature with remarkable potential to prognosis and anticipate immunotherapeutic outcomes in LUAD patients.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Prognóstico , RNA , Sequência de Bases , Adenocarcinoma de Pulmão/genética , Complexo CD3 , Neoplasias Pulmonares/genética , Microambiente Tumoral/genética
2.
Angew Chem Int Ed Engl ; 63(10): e202316966, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38217483

RESUMO

LiPF6 as a dominant lithium salt of electrolyte is widely used in commercial rechargeable lithium-ion batteries due to its well-balanced properties, including high solubility in organic solvents, good electrochemical stability, and high ionic conductivity. However, it suffers from several undesirable properties, such as high moisture sensitivity, thermal instability, and high cost. To address these issues, herein, we propose an electron-donation modulation (EDM) rule for the development of low-cost, sustainable, and electrochemically compatible LiNO3 -based electrolytes. We employ high donor-number solvents (HDNSs) with strong electron-donation ability to dissolve LiNO3 , while low donor-number solvents (LDNSs) with weak electron-donation ability are used to regulate the solvation structure to stabilize the electrolytes. As an example, we design the LiNO3 -DMSO@PC electrolyte, where DMSO acts as an HDNS and PC serves as an LDNS. This electrolyte exhibits excellent electrochemical compatibility with graphite anodes, as well as the LiFePO4 and LiCoO2 cathodes, leading to stable cycling over 200 cycles. Through spectroscopy analyses and theoretical calculation, we uncover the underlying mechanism responsible for the stabilization of these electrolytes. Our findings provide valuable insights into the preparation of LiNO3 -based electrolytes using the EDM rule, opening new avenues for the development of advanced electrolytes with versatile functions for sustainable rechargeable batteries.

3.
ACS Appl Mater Interfaces ; 14(38): 43387-43396, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36098664

RESUMO

Sodium metal is a promising anode for high-energy-density sodium rechargeable batteries (RSBs). However, the low Coulombic efficiency (CE) of the Na plating/stripping process and the problem of safety hinder their practical application. Herein, we report a facile strategy for employing the fluorinated phosphate solvents to realize highly reversible Na plating/stripping and improve the safety performance. The fluorinated phosphate molecules reduce the polarity of the solvent and lower the coordination number to Na+, which makes it possible to form the anion-induced ion-solvent-coordinated (AI-ISC) structures with high reduction tolerance. Moreover, the fluorination treatment enhances the oxidation resistance of the phosphate solvent, enabling compatibility with the high-voltage Na3V2(PO4)2F3 (NVPF) cathode. As expected, the Na@Al//NVPF full cell with the as-prepared 0.9 M NaFSI/tris(2,2,2-trifluoroethyl) phosphate (TFEP) demonstrates a capacity retention of 83.4% after 200 cycles with an average CE of 99.6%. This work opens a new avenue for designing high-energy-density RSBs with improved safety performance.

4.
ACS Appl Mater Interfaces ; 14(1): 574-580, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34936327

RESUMO

Propylene carbonate (PC)-based electrolytes have many attractive advantages over the commercially used ethylene carbonate (EC)-based electrolytes like a wider operating temperature and higher oxidation stability. Therefore, PC-based electrolytes become the potential candidate for lithium-ion batteries with higher energy density, longer lifespan, and better low- and high-temperature performance. In spite of the superiority, PC is incompatible with the graphite anode because PC fails to passivate the graphite anode, leading to severe decomposition and gas evolution, which seriously restrict the development of the PC-based electrolytes. Nevertheless, it is recently found that the usage of diethyl carbonate (DEC) as a cosolvent will greatly improve the anodic tolerance of PC to realize the reversible lithiation/delithiation of the graphite anode in the PC-based electrolyte. It is because DEC induces anions into the solvation shell of Li+ to form an anion-induced ion-solvent-coordinated (AI-ISC) structure with higher reduction stability. In this work, we fabricated 4.4 V pouch cells to assess in detail the practical viability of the PC-based electrolyte in a commercial battery system. In comparison to conventionally used EC-based cells, the pouch cells with the PC-based electrolyte exhibit more excellent high-voltage tolerance and electrochemical performance at all temperature ranges (-40 to 85 °C), demonstrating the wide application prospect of the PC-based electrolyte.

5.
Chem Sci ; 12(26): 9037-9041, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34276932

RESUMO

Many organic solvents have very desirable solution properties, such as wide temperature range, high solubility of Li salts and nonflammability, and should be able but fail in reality to serve as electrolyte solvents for Li-ion or -metal batteries due to their reduction instability. The origin of this interfacial instability remains unsolved and disputed so far. Here, we reveal for the first time the origin of the reduction stability of organic carbonate electrolytes by combining ab initio molecular dynamics (AIMD) simulations, density functional theory (DFT) calculations and electrochemical stability experiments. It is found that with the increase of the molar ratio (MR) of salt to solvent, the anion progressively enters into the solvation shell of Li+ to form an anion-induced ion-solvent-coordinated (AI-ISC) structure, leading to a "V-shaped" change of the LUMO energy level of coordinated solvent molecules, whose interfacial stability first decreases and then increases with the increased MRs of salt to solvent. This mechanism perfectly explains the long-standing puzzle about the interfacial compatibility of organic electrolytes with Li or similar low potential anodes and provides a basic understanding and new insights into the rational design of the advanced electrolytes for next generation lithium secondary batteries.

6.
Materials (Basel) ; 13(21)2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33158144

RESUMO

The Mg-0.6Al-20.8Gd (wt.%) alloys were homogenized at 620 °C for 20 min under 0 T and 1 T, followed by furnace cooling, quenching, and air cooling, respectively. The effects of the magnetic field on the phase constituent, microstructure, secondary phase precipitation, and mechanical properties of the Mg-Al-Gd alloys were investigated. The Mg-Al-Gd alloys contained α-Mg, Mg5Gd, Al2Gd, and GdH2 phases, and the phase constituents were hardly influenced by the applied magnetic field. However, the precipitation of the paramagnetic Mg5Gd upon cooling was accelerated by the magnetic field, and that of the ferromagnetic Al2Gd phases was inhibited. In addition, the Al2Gd phase was significantly refined and driven to segregate at the grain boundaries by the magnetic field, and the resultant pinning effect led to the microstructure change from dendritic α-Mg grains to rosette-like ones. When the magnetic field was only applied to the homogenization stage, the content of the Mg5Gd phase remained unchanged in the quenched alloy, whereas the Mg5Gd laths were significantly refined. By contrast, the contents of the Al2Gd and GdH2 phases were increased, while the precipitation sites were still within the α-Mg grains. The Mg5Gd laths were incapable of providing precipitation strengthening, while the Al2Gd and GdH2 particles brought positive effects on the enhancement of the mechanical properties. In the quenching condition, the hardness, compression strength, and ductility can be improved by the magnetic treatment, whereas these mechanical properties can be suppressed in the furnace cooled condition by the magnetic treatment.

7.
Fish Shellfish Immunol ; 107(Pt A): 309-323, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33096248

RESUMO

The immune function of immune organs is extremely crucial for maintaining organism health status, which ultimately affects fish growth. Our previous study has found that dietary supplementation of (2-carboxyethyl)dimethylsulfonium Bromide (Br-DMPT) in non-fish meal (NFM) diet could promote the growth of grass carp (Ctenopharyngodon idella), whereas the underlying reason or mechanism for this results is largely unclear. Herein, we further explored whether dietary supplementation of Br-DMPT promoted fish growth is connected with the enhanced immune function in the immune organs (the head kidney, spleen and skin). In this study, 540 fish (216.49 ± 0.29 g) were irregularly distributed to six groups with three replicates (30 fish replicate-1) and fed corresponding diets group containing a fish meal (FM) diet group and five different NFM diets supplemented with gradational Br-DMPT (0-520.0 mg/kg level) group for 60 days. After the 60-days feeding trial, 8 fish from each replicate were selected and then conducted a challenge test with A. hydrophila for 14 days. Our results indicated that in the NFM diets, appropriate Br-DMPT: (1) significantly decreased the morbidity of skin haemorrhage and lesion after A. hydrophila infection (P < 0.05). (2) significantly improved the innate and adaptive immune components (lysozyme, complement 3, immunoglobulin M and antibacterial peptides et al.) (P < 0.05). (3) increased the gene expressions of main anti-inflammatory cytokines partially by referring to TOR signalling pathway, and decreased the gene expressions of main pro-inflammatory cytokines partially by referring to NF-kB signalling pathway (P < 0.05). Strikingly, no statistical difference could be found in the most of above immune parameters between 260.0 mg/kg Br-DMPT diet group and FM diet group (P > 0.05). Taken together, in non-fish meal diet, appropriate supplementation of Br-DMPT could improve the disease resistance capacity, non-specific immunity and ameliorate inflammation, and simultaneously could mitigate these adverse effects induced by the non-fish meal diet in fish immune organs. Moreover, this study may be helpful to decipher the underlying mechanisms of how Br-DMPT promote fish growth by immune organs and also provide scientific theoretical evidence for the future application of Br-DMPT as a new immunopotentiator in aquaculture industry.


Assuntos
Carpas/imunologia , Substâncias Protetoras/metabolismo , Compostos de Sulfônio/metabolismo , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Substâncias Protetoras/administração & dosagem , Compostos de Sulfônio/administração & dosagem
8.
Fish Shellfish Immunol ; 106: 228-240, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32771611

RESUMO

In this study, the protective effects and potential mechanisms of (2-Carboxyethyl) dimethylsulfonium Bromide (Br-DMPT) were evaluated in relation to the gill health status of on-growing young grass carp (Ctenopharyngodon idella). A total of 450 grass carp (216.49 ± 0.29 g) were randomly distributed into five treatments of three replicates each (30 fish per replicate) and were fed diets supplemented with gradational Br-DMPT (0-520.0 mg/kg levels) for 60 days. Subsequently, the fish were challenged with Flavobacterium columnare for 3 days, and the gills were sampled to evaluate antioxidant status and immune responses evaluation. Our results showed that, when compared to the control group, dietary supplementation with appropriate Br-DMPT levels resulted in the following: (1) decreased gill rot morbidity and improved gill histological symptoms after exposure to F. columnare (P < 0.05); (2) improved activities and gene expression levels (except GSTP2 gene) of antioxidant enzymes and decreased oxidative damage parameter values (reactive oxygen species, malondialdehyde and protein carbonyl) (P < 0.05), which may be partially associated with the nuclear factor-erythroid 2-related factor 2 (Nrf2) signalling pathway (P < 0.05); (3) increased lysozyme (LZ) and acid phosphatase (ACP) activities and complement 3 (C3), C4 and immunoglobulin M (IgM) contents, and upregulated genes expressions of antibacterial peptides (liver-expressed antimicrobial peptide-2A, -2B, hepcidin, ß-defensin and mucin2) (P < 0.05); (4) upregulated gene expressions of anti-inflammatory cytokines (except IL--4/13B) that may be partially to the TOR/(S6K1, 4E-BP1) signalling pathway, and downregulated gene expressions of pro-inflammatory cytokines (except IL-12P35) may be partially to the IKK ß, γ/IκBα/NF-kB) signalling pathway (P < 0.05). Taken together, our results indicate that dietary supplementation with appropriate amounts of Br-DMPT may effectively protect on-growing grass carp from F. columnare by strengthening gill antioxidant capacity and immunity. Furthermore, based on measures of combatting gill rot, antioxidant indices (MDA) and immune indices (LZ), the dietary Br-DMPT supplementation levels for on-growing grass carp are recommended to be 291.14, 303.38 and 312.01 mg/kg diet, respectively.


Assuntos
Brometos/metabolismo , Carpas/imunologia , Substâncias Protetoras/metabolismo , Compostos de Sulfônio/metabolismo , Ração Animal/análise , Animais , Brometos/administração & dosagem , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Substâncias Protetoras/administração & dosagem , Distribuição Aleatória , Compostos de Sulfônio/administração & dosagem
9.
Chem Commun (Camb) ; 56(48): 6559-6562, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32396155

RESUMO

We develop a new type of electrolyte with a high molar ratio (MR) of salt to solvent but a low molar concentration by adjusting the molar mass of the solvent. The present 1 : 2 LiFSI-triamyl phosphate electrolyte exhibits a low molar concentration of only 1.35 M along with excellent electrochemical stability against the graphite anode.

10.
Fish Shellfish Immunol ; 98: 534-550, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32004614

RESUMO

The present study evaluated the effects of (2-Carboxyethyl)dimethylsulfonium Bromide (Br-DMPT) supplementation on the intestinal immune function and potential mechanisms of on-growing grass carp (Ctenopharyngodon idella) by feeding fish (initial weight 216.49 ± 0.29 g) five diets with gradational Br-DMPT (0-520 mg/kg diet) concentrations for 60 days and then infecting them with Aeromonas hydrophila for 14 days. Our results firstly indicated that compared with the control group, appropriate Br-DMPT supplementation increased the number of beneficial bacteria Lactobacillus and Bifidobacterium and enteritis resistance, decreased the number of detrimental bacteria Aeromonas and E. coli, and relieved the intestinal histopathological symptoms of fish. In addition, compared with the control group, appropriate Br-DMPT supplementation (1) increased lysozyme (LZ) and acid phosphatase (ACP) activities, as well as complement 3 (C3), C4 and immunoglobulin M (IgM) content; (2) upregulated the mRNA levels of anti-microbial substance: liver expressed anti-microbial peptide (LEAP) -2A, LEAP-2B, hepcidin, ß-defensin-1 and Mucin2; (3) partially downregulated the mRNA levels of pro-inflammatory cytokines [interleukin 1ß (IL-1ß), IL-6, IL-8, IL-12p40, IL-15, IL-17D, tumour necrosis factor α (TNF-α) and interferon γ2 (IFN-γ2)] by inhibiting [IKKß/IκBα/(NF-κBp65 and c-Rel)] signalling; and (4) partially upregulated the mRNA levels of anti-inflammatory cytokines [IL-4/13A, IL-10, IL-11, transforming growth factor (TGF)-ß1] by activating [TOR/(S6K1 and 4E-BP)] signalling. The aforementioned results indicated that appropriate amount of Br-DMPT exerted a positive effect on the regulation of intestinal immune function in fish. Finally, based on enteritis morbidity, the IgM content and the lysozyme activity in the PI, the appropriate levels of Br-DMPT supplementation for on-growing grass carp were established as 295.43, 301.73 and 320.36 mg/kg diet, respectively.


Assuntos
Carpas , Intestinos/efeitos dos fármacos , Intestinos/imunologia , Compostos de Sulfônio/farmacologia , Animais , Antiulcerosos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Intestinos/microbiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
11.
Aging (Albany NY) ; 12(2): 1171-1185, 2020 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-31977318

RESUMO

Hepatocellular carcinoma (HCC) is a common malignancy with a dismal prognosis. It is of great importance to identify biomarkers for the prediction of patients' survival.The mRNA expression level of deoxyribonuclease 1 like 3 (DNASE1L3) and its correlation with survival were accessed in 424 samples from The Cancer Genome Atlas database. Its expression level was confirmed by real-time quantitative polymerase chain reaction and western blotting in 20 pairs of postsurgical specimens. In addition, immunohistochemistry staining of DNASE1L3 was also performed in 113 postoperative samples, using a histochemistry score system. The relationship between patients' survival and DNASE1L3 expression level was evaluated by the Kaplan-Meier method.DNASE1L3 is downregulated in both mRNA and protein levels in HCC tissues, compared with adjacent normal tissues. 52 of 113 HCC specimens showed positive DNASE1L3 protein expression. Patients with positive DNASE1L3 expression had significantly longer overall survival, compared with patients with negative expression (p = 0.023). However, the DNASE1L3 fails to discriminate progression-free survival (p = 0.134). Multivariate COX analysis revealed that positive DNASE1L3 expression and higher differentiation were significantly associated with better overall survival.This study demonstrated that positive DNASE1L3 expression is an independent prognostic factor for better survival in HCC patients following radical resection.


Assuntos
Biomarcadores Tumorais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/mortalidade , Endodesoxirribonucleases/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Biologia Computacional/métodos , Feminino , Regulação Neoplásica da Expressão Gênica , Hepatectomia , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Prognóstico , Reprodutibilidade dos Testes , Análise de Sobrevida , Transcriptoma , Carga Tumoral
12.
ACS Appl Mater Interfaces ; 11(31): 27833-27838, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31287282

RESUMO

Sodium-ion batteries (SIBs) have been viewed as a promising candidate for grid-scale energy storage systems owing to their low cost and abundant Na resources. However, insufficient safety and poor cycling performance of current SIBs are hampering their implementation. Herein, we develop a symmetric SIB by employing Na3V2(PO4)3 as both cathode and anode along with the nonflammable triethyl phosphate dissolving 0.9 M NaClO4 as the electrolyte. The symmetric SIB demonstrates a superior rate capability (35.1 mA h g-1 at 32 C) and excellent cycling performance with a capacity retention of 88.9% after 500 cycles at 2 C. This work demonstrates a new avenue to construct safe and long-cycle-life SIBs with a simple electrode manufacturing process.

13.
Skin Res Technol ; 25(4): 447-455, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30614573

RESUMO

OBJECTIVES: To investigate the characteristics of hairs in Female pattern hair loss (FPHL) patients and healthy females in Southern China. MATERIALS AND METHODS: Three fundamental hair parameters in different scalp areas of 90 Southern Chinese FPHL patients and 83 healthy controls were analyzed by phototrichogram. RESULTS: Female pattern hair loss patients showed reduced hair density, hair diameter, and terminal/vellus hair ratio. The reduction correlated with the severity of Ludwig staging. Midscalp was the most affected area in FPHL, but occipital and temporal sites were also involved. In normal women, the highest hair density was observed in midscalp, followed by occipital and temporal areas. Peak hair density at midscalp sites was reached at 20s group, then declined with age. Maximum hair diameter at midscalp and occipital sites occurred in 40s group. Terminal/vellus hair ratio tended to increase with age and peak on 50-60s group. CONCLUSION: Reduced hair density and hair diameter, and miniaturization of hair follicles are the characteristics of FPHL in Southern Chinese women. Occipital and temporal sites are also affected in FPHL. Age-associated changes might have an influence on the hair condition. The values of hair parameters obtained in this study will help to establish reference data for better evaluation of hair disorders.


Assuntos
Alopecia/classificação , Folículo Piloso/crescimento & desenvolvimento , Couro Cabeludo/diagnóstico por imagem , Adulto , Alopecia/patologia , Povo Asiático/etnologia , Contagem de Células , Feminino , Cabelo/anormalidades , Cabelo/citologia , Cabelo/crescimento & desenvolvimento , Folículo Piloso/diagnóstico por imagem , Folículo Piloso/patologia , Humanos , Pessoa de Meia-Idade , Couro Cabeludo/patologia , Índice de Gravidade de Doença
14.
Neurol Sci ; 40(4): 779-791, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30671738

RESUMO

BACKGROUND: Recent evidences have implicated neuroprotective effects of CX3CR1 in multiple sclerosis (MS). But whether CX3CR1 is involved in modulation of antigen-presenting cell (APC)-related molecular MHC-II and what the possible mechanism is remain unidentified. OBJECTIVE: In this study, we intended to investigate the effects of CX3CR1 on MHC-II expressions on brain myeloid cells in experimental autoimmune encephalomyelitis (EAE) mice and explore the possible regulators for it. METHODS: CX3CR1-deficient EAE mice were created. Disease severity, pathological damage, and the expressions of MHC-II and its mediators on myeloid cells were detected. RESULTS: We found that compare with wile-typed EAE mice, CX3CR1-deficient EAE mice exhibited more severe disease severity. An accumulation of CD45+CD115+Ly6C-CD11c+ cells was reserved in the affected EAE brain of CX3CR1-deficient mice, consistent with disease severity and pathological damage in the brain. The expressions of MHC-II on the brain CD45+CD115+Ly6C-CD11c+ cells of CX3CR1-deficient EAE mice were elevated, in accord with the increased protein and mRNA expressions of class II transactivator (CIITA) and interferon regulatory factor-1 (IRF-1). CONCLUSIONS: The findings indicated that CX3CR1 might be an important regulator for MHC-II expressions on APCs, playing a beneficial role in EAE. The mechanism was probably through regulation on the MHC-II regulators CIITA and IRF-1.


Assuntos
Células Apresentadoras de Antígenos/metabolismo , Receptor 1 de Quimiocina CX3C/metabolismo , Encefalomielite Autoimune Experimental , Antígenos de Histocompatibilidade Classe II/metabolismo , Inflamação , Fator Regulador 1 de Interferon/metabolismo , Esclerose Múltipla , Proteínas Nucleares/metabolismo , Transativadores/metabolismo , Animais , Receptor 1 de Quimiocina CX3C/deficiência , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/metabolismo , Encefalomielite Autoimune Experimental/patologia , Encefalomielite Autoimune Experimental/fisiopatologia , Feminino , Inflamação/metabolismo , Inflamação/patologia , Inflamação/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Esclerose Múltipla/fisiopatologia , Células Mieloides/metabolismo
15.
Acta Crystallogr B Struct Sci Cryst Eng Mater ; 75(Pt 2): 134-142, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32830737

RESUMO

The microstructure evolution and changes in the structures of crystal defects of the nanocrystalline WC-Co composite in the process of uniaxial compression were studied by simulations at both room and high temperatures. The deformation processes were demonstrated as a function of stress and temperature for the stages prior to and after yielding of the composite. The Peierls stresses were evaluated for Co and WC dislocations with increasing temperature. The deformation mechanisms for each stage of the stress-strain curve were disclosed, in which the effect of temperature was clarified. It was found that with the increase of stress, from elastic deformation to plastic deformation then to yielding of the composite, the dominant mechanisms are grain boundary migration, formation and motion of dislocations in Co, concurrent motion and reaction of dislocations in Co and WC, and then rotation of WC grains in combination with motion of Co and WC dislocations. At the yielding stage, sliding of WC grain boundaries plays an increasingly important role in the contribution to plastic deformation at high temperatures. With strain the proportion of mobile dislocations decreases, and dislocations pile up at triple junctions of WC grains, WC/WC grain boundaries and WC/Co phase boundaries in priority order, leading to the nucleation and propagation of microcracks in these regions.

16.
iScience ; 10: 114-122, 2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30513393

RESUMO

Most of the currently developed sodium-ion batteries (SIBs) have potential safety hazards due to the use of highly volatile and flammable alkyl carbonate electrolytes. To overcome this challenge, we report an electrochemically compatible and nonflammable electrolyte, tris(2,2,2-trifluoroethyl) phosphate (TFEP) with low-concentration sodium bis(fluorosulfonyl)imide (0.9 M), which is designed not only to match perfectly with the hard carbon (HC) anode but also to enhance the thermal stability of SIBs. Experimental results and theoretical calculations reveal that TFEP molecules have a significantly low barrier to decompose before Na+ inserts into HC, forming a stable inorganic solid-electrolyte interface layer, thus improving the electrochemical and structural stabilities of HC anodes. An HC/Na3V2(PO4)3 full cell using TFEP electrolyte shows a high capacity retention of 89.2% after 300 cycles and a dramatically reduced exothermic heat at elevated temperature, implying its potential application for safe and low-cost larger-scale energy storage.

17.
ACS Appl Mater Interfaces ; 10(44): 38141-38150, 2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30335351

RESUMO

Nonflammable phosphate electrolytes are in principle able to build intrinsically safe Na-ion batteries, but their electrochemical incompatibility with anodic materials, especially hard carbon anode, restricts their battery applications. Here, we propose a new strategy to enable high-capacity utilization and cycle stability of hard carbon anodes in the nonflammable phosphate electrolyte by using low-cost Na+ salt with a high molar ratio of salt/solvent combined with an solid electrolyte interphase film-forming additive. As a result, the carbon anode in the trimethyl phosphate (TMP) electrolyte with a high molar ratio of [NaClO4]/[TMP] and 5% fluoroethylene carbonate additive demonstrates a high reversible capacity of 238 mAh g-1, considerable rate capability, and long-term cycling life with 84% capacity retention over 1500 cycles. More significantly, this work provides a promising route to build intrinsically safe and low-cost sodium-ion batteries for large-scale energy storage applications.

18.
Clin Neurol Neurosurg ; 171: 79-84, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29870886

RESUMO

OBJECTIVES: The aim of this study is to investigate the association of HDL-C with CCAS, as well as its intracranial or extracranial location in the Southern Chinese population. PATIENTS AND METHODS: 123 Southern Chinese patients with large-artery atherosclerotic(LAA) ischemic stroke were enrolled for the final analysis. Based on the stenosis severity defined by digital subtraction angiography, the patients were categorized into CCAS and non-CCAS groups. The degree of artery stenosis among patients of CCAS was classified into three grades. CCAS were further categorized into intracranial AS (ICAS), Extracranial AS (ECAS) and combined intra-/extra-cranial AS (IECAS). RESULTS: It was showed that patients with CCAS had a lower HDL-C level compared to NCCAS, and HDL-C levels were correlated to the degree of artery stenosis among CCAS. After adjusting for multiple potential confounders, low HDL-C level remained independently associated with CCAS(adjusted OR = 2.860). Patients with the lowest HDL-C quartile had a significantly increased risk for CCAS(adjusted OR: 5.771), referred to the highest quartile. But HDL-C levels in patients with ICAS, ECAS and IECAS were not significantly different, and there was no significant correlation between HDL-C levels and ICAS. CONCLUSION: Our data indicate that low HDL-C level is associated with CCAS in Southern Chinese patients with LAA ischemic stroke. But the effects of HDL-C on the distribution of CCAS is required to be further explored.


Assuntos
Estenose das Carótidas/etiologia , HDL-Colesterol/sangue , Arteriosclerose Intracraniana/etiologia , Acidente Vascular Cerebral/epidemiologia , Idoso , Povo Asiático , Aterosclerose , Constrição Patológica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Acidente Vascular Cerebral/sangue
19.
Artigo em Inglês | MEDLINE | ID: mdl-29794989

RESUMO

Solute transport modeling resolves advection, dispersion, and chemical reactions in groundwater systems with its accuracy depending on the resolution of domain at all scales, thus the computational efficiency of a simulator becomes a bottleneck for the wide application of numerical simulations. However, the traditional serial numerical simulators have reached their limits for the prohibitive computational time and memory requirement in solving large-scale problems. These limitations have greatly hindered the wide application of groundwater solute transport modeling. Thus, the development of an efficient method for handling large-scale groundwater solute transport simulation is urgently required. In this study, we developed and assessed a parallelized MT3DMS (Modular Three-Dimensional Multispecies Transport Model) by using OpenMP (Open specifications for Multi-Processing) to accelerate the solute transport simulation process. The parallelization was achieved by adding OpenMP compile directives (i.e., defining various types of parallel regions) into the most time-consuming packages, including the Advection package (ADV), Dispersion package (DSP), and Generalized Conjugate Gradient Solver package (GCG). This allows parallel processing on shared-memory multiprocessors, i.e., both the memory requirement and computing efforts are automatically distributed among all processors. Moreover, we discussed two different parallelization strategies for handling numerical models with either many layers or few layers. The performance of parallelized MT3DMS was assessed by two benchmark numerical models with different model domain sizes via a workstation with two quad-core processors. Results showed that the running time of parallelized MT3DMS can be 4.15 times faster than that using sequential MT3DMS. The effects of using different preconditioners (procedures that transform a given problem into a form that is more suitable for numerical solving methods) in the GCG package were additionally evaluated. The modified strategy for handling numerical models with few layers also achieved satisfactory results with running time two times faster than that via sequential simulation. Thus, the proposed parallelization allows high-resolution groundwater transport simulation with higher efficiency for large-scale or multimillion-cell simulation problems.


Assuntos
Água Subterrânea/química , Modelos Teóricos , Movimentos da Água
20.
R Soc Open Sci ; 5(3): 171712, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29657776

RESUMO

A photoelectric conversion efficiency (PCE) of 4.9% was obtained under 100 mW cm-2 illumination by quantum-dot-sensitized solar cells (QDSSCs) using a CdS/Mn : CdSe sensitizer. CdS quantum dots (QDs) were deposited on a TiO2 mesoporous oxide film by successive ionic layer absorption and reaction. Mn2+ doping into CdSe QDs is an innovative and simple method-chemical bath co-deposition, that is, mixing the Mn ion source with CdSe precursor solution for Mn : CdSe QD deposition. Compared with the CdS/CdSe sensitizer without Mn2+ incorporation, the PCE was increased from 3.4% to 4.9%. The effects of Mn2+ doping on the chemical, physical and photovoltaic properties of the QDSSCs were investigated by energy dispersive spectrometry, absorption spectroscopy, photocurrent density-voltage characteristics and electrochemical impedance spectroscopy. Mn-doped CdSe QDs in QDSSCs can obtain superior light absorption, faster electron transport and slower charge recombination than CdSe QDs.

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