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1.
Small ; 20(28): e2311055, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38295001

RESUMO

Through inducing interlayer anionic ligands and functionally modifying conductive carbon-skeleton on the transition metal chalcogenides (TMCs) parent to achieve atomic-level defect-manipulation and nanoscopic-level architecture design is of great significance, which can broaden interlayer distance, optimize electronic structure, and mitigate structural deformation to endow high-efficiency battery performance of TMCs. Herein, an intriguing 3D biconcave hollow-tyre-like anode constituted by carbon-packaged defective-rich SnSSe nanosheet grafting onto Aspergillus niger spores-derived hollow-carbon (ANDC@SnSSe@C) is reported. Systematically experimental investigations and theoretical analyses forcefully demonstrate the existence of anion Se ligand and outer-carbon all-around encapsulation on the ANDC@SnSSe@C can effectively yield abundant structural defects and Na+-reactivity sites, accelerate rapid ion migration, widen interlayer spacing, as well as relieve volume expansion, thus further resolving the critical issues throughout the charge-discharge processes. As anticipated, as-fabricated ANDC@SnSSe@C anode contributes extraordinary reversible capacity, wonderful cyclic lifespan with 83.4% capacity retention over 2000 cycles at 20.0 A g-1, and exceptional rate capability. A series of correlated kinetic investigations and ex situ characterizations deeply reveal the underlying springheads for the ion-transport kinetics, as well as synthetically elucidate phase-transformation mechanism of the ANDC@SnSSe@C. Furthermore, the ANDC@SnSSe@C-based sodium ion full cell and hybrid capacitor offer high-capacity contribution and remarkable energy-density output, indicative of its great practicability.

2.
Econ Lett ; 224: 110999, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36778078

RESUMO

This study investigates the relationship between political connections and firm financial performance during the COVID-19 pandemic. Using a difference-in-differences methodology, we found that politically connected enterprises paid more taxes, employed more employees, and suffered financial performance. This study enriches the literature on the impact of COVID-19 on enterprises and provides suggestions for regulators.

3.
J Chem Inf Model ; 60(12): 5870-5872, 2020 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-33058674

RESUMO

Modern scientometric techniques, applied at scale, can provide valuable information that complements qualitative investigation of the accumulation of knowledge in a field. We discuss a trio of articles from computational chemistry selected from an analysis of 181 million tri-cited articles.


Assuntos
Bibliometria , Quimioinformática
4.
Nanotechnology ; 31(48): 485701, 2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-32931462

RESUMO

The electronic structures of two dimensional (2D) CdS/ZnO heterostructure (CdZnHT) consisting of CdS singlelayer (SL) and ZnO SL are explored based on hybrid density functional calculation. The negative interface formation energies suggest the formation of CdZnHT is exothermic. The bandgap of CdZnHT is favorable for absorbing visible light, and the decent band edge position makes it thermodynamically feasible for spontaneous generation of oxygen and hydrogen. The formed electric field across the interface induced by charge transfer will reduce photogenerated carrier recombination and promote carrier migration. Particularly, CdZnHT is a type-II heterostructure. Oxygen generation takes place at ZnO layer and hydrogen production occurs at CdS layer, which will also promote the effective separation and migration of phogogenerated carriers and enhance photocatalytic performance. These findings suggest that 2D CdZnHTs are possible candidates as water-splitting photocatalysts.

5.
Mol Med Rep ; 29(6)2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38577930

RESUMO

Emerging scientific evidence has suggested that the long non­coding (lnc)RNA differentiation antagonizing non­protein coding RNA (DANCR) serves a significant role in human tumorigenesis and cancer progression; however, the precise mechanism of its function in breast cancer remains to be fully understood. Therefore, the objective of the present study was to manipulate DANCR expression in MCF7 and MDA­MB­231 cells using lentiviral vectors to knock down or overexpress DANCR. This manipulation, alongside the analysis of bioinformatics data, was performed to investigate the potential mechanism underlying the role of DANCR in cancer. The mRNA and/or protein expression levels of DANCR, miR­34c­5p and E2F transcription factor 1 (E2F1) were assessed using reverse transcription­quantitative PCR and western blotting, respectively. The interactions between these molecules were validated using chromatin immunoprecipitation and dual­luciferase reporter assays. Additionally, fluorescence in situ hybridization was used to confirm the subcellular localization of DANCR. Cell proliferation, migration and invasion were determined using 5­ethynyl­2'­deoxyuridine, wound healing and Transwell assays, respectively. The results of the present study demonstrated that DANCR had a regulatory role as a competing endogenous RNA and upregulated the expression of E2F1 by sequestering miR­34c­5p in breast cancer cells. Furthermore, E2F1 promoted DANCR transcription by binding to its promoter in breast cancer cells. Notably, the DANCR/miR­34c­5p/E2F1 feedback loop enhanced cell proliferation, migration and invasion in breast cancer cells. Thus, these findings suggested that targeting DANCR may potentially provide a promising future therapeutic strategy for breast cancer treatment.


Assuntos
Neoplasias da Mama , MicroRNAs , RNA Longo não Codificante , Humanos , Feminino , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias da Mama/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Linhagem Celular Tumoral , Retroalimentação , Hibridização in Situ Fluorescente , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Fator de Transcrição E2F1/genética , Fator de Transcrição E2F1/metabolismo
6.
Adv Mater ; 36(4): e2305190, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37640375

RESUMO

New-fashioned electrode hosts for sodium-ion batteries (SIBs) are elaborately engineered to involve multifunctional active components that can synergistically conquer the critical issues of severe volume deformation and sluggish reaction kinetics of electrodes toward immensely enhanced battery performance. Herein, it is first reported that single-phase CoPS, a new metal phosphosulfide for SIBs, in the form of quantum dots, is successfully introduced into a leaf-shaped conductive carbon nanosheet, which can be further in situ anchored on a 3D interconnected branch-like N-doped carbon nanofiber (N-CNF) to construct a hierarchical branch-leaf-shaped CoPS@C@N-CNF architecture. Both double carbon decorations and ultrafine crystal of the CoPS in-this exquisite architecture hold many significant superiorities, such as favorable train-relaxation, fast interfacial ion-migration, multi-directional migration pathways, and sufficiently exposed Na+ -storage sites. In consequence, the CoPS@C@N-CNF affords remarkable long-cycle durability over 10 000 cycles at 20.0 A g-1 and superior rate capability. Meanwhile, the CoPS@C@N-CNF-based sodium-ion full cell renders the potential proof-of-feasibility for practical applications in consideration of its high durability over a long-term cyclic lifespan with remarkable reversible capacity. Moreover, the phase transformation mechanism of the CoPS@C@N-CNF and fundamental springhead of the enhanced performance are disclosed by in situ X-ray diffraction, ex situ high-resolution TEM, and theoretical calculations.

7.
Adv Mater ; 36(25): e2401221, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38563723

RESUMO

Renewable electricity-powered nitrate/carbon dioxide co-reduction reaction toward urea production paves an attractive alternative to industrial urea processes and offers a clean on-site approach to closing the global nitrogen cycle. However, its large-scale implantation is severely impeded by challenging C-N coupling and requires electrocatalysts with high activity/selectivity. Here, cobalt-nanoparticles anchored on carbon nanosheet (Co NPs@C) are proposed as a catalyst electrode to boost yield and Faradaic efficiency (FE) toward urea electrosynthesis with enhanced C-N coupling. Such Co NPs@C renders superb urea-producing activity with a high FE reaching 54.3% and a urea yield of 2217.5 µg h-1 mgcat. -1, much superior to the Co NPs and C nanosheet counterparts, and meanwhile shows strong stability. The Co NPs@C affords rich catalytically active sites, fast reactant diffusion, and sufficient catalytic surfaces-electrolyte contacts with favored charge and ion transfer efficiencies. The theoretical calculations reveal that the high-rate formation of *CO and *NH2 intermediates is crucial for facilitating urea synthesis.

8.
J Clin Biochem Nutr ; 52(3): 244-52, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23704815

RESUMO

The purpose of this study was to investigate the protective effect of polysaccharides from Boschniakia rossica against hepatotoxicity induced by carbon tetrachloride (CCl4). Boschniakia rossica polysaccharides was administered intragastrically once daily for 7 days. One hour after the final treatment, mice were treated intraperitoneally with 80 mg/kg of CCl4. CCl4-induced hepatotoxicity was manifested by increased levels of serum marker enzymes and hepatic lipid peroxidation, and by decreased potential of hepatic antioxidative defense system. CCl4 challenge also resulted in elevated serum tumor necrosis factor-α and hepatic nitric oxide level, and up-regulation of inducible nitric oxide synthase and cyclooxygenase-2 proteins of liver tissue. Pretreatment of mice with Boschniakia rossica polysaccharides reversed these altered parameters of mice with liver injury induced by CCl4. Furthermore, caspase-3 cleavage and activities, and DNA fragmentation of liver in mice treated with Boschniakia rossica polysaccharides were decreased than mice treated with CCl4 alone. Hepatoprotective effect of Boschniakia rossica polysaccharides was further demonstrated by histopathological examination of liver sections. The results indicate that Boschniakia rossica polysaccharides play a protective role in CCl4-induced acute liver injury and the hepatoprotective effect of Boschniakia rossica polysaccharides may be due to elevated antioxidative defense potentials, suppressed inflammatory responses and apoptosis of liver tissue.

9.
Zhongguo Zhong Yao Za Zhi ; 38(13): 2187-90, 2013 Jul.
Artigo em Zh | MEDLINE | ID: mdl-24079251

RESUMO

OBJECTIVE: To investigate the protective effect of soyasaponins on acute liver injury induced by D-galactosamine (GalN) and lipopolysaccharide (LPS) in mice. METHOD: The mice were randomly divided into five groups: the normal control, the model group, the silymarin (positive control) group, and soyasaponins high and low-dose groups. They were administered with drugs once every day for 7 days. At the end of the experiment, GalN and LPS were injected intraperitoneally to all of the groups except for the normal group to establish the acute liver injury model. The pathological changes were detected with hematoxylin & eosin (HE) staining, tumor necrosis factor-alpha (TNF-alpha) was detected by ELISA method, and the alanine aminotransferase (ALT), aspartate aminotransferase (AST), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST), reduced glutathione (GSH), malondialdehyde (MDA), nitric oxide (NO), and the activation of Caspase-3 and Caspase-8 were detected by the colorimetric method. RESULT: Soyasaponins could reduce the activities of serum ALT and AST, the acute hepatic injury induced by GalN/LPS, serum TNF-alpha level, hepatic NO and MDA contents, and the Caspase-3 and Caspase-8 activations of liver tissues, and increase the hepatic CAT, GPx, GST and GSH levels. CONCLUSION: Soyasaponins shows the protective effect on acute liver injury induced by GalN and LPS in mice, which may be related to its antioxidative ability and anti-liver apoptosis.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Glycine max/química , Saponinas/farmacologia , Alanina Transaminase/sangue , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Aspartato Aminotransferases/sangue , Caspases/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Galactosamina/toxicidade , Lipopolissacarídeos/toxicidade , Fígado/patologia , Masculino , Camundongos
10.
Zhongguo Zhong Yao Za Zhi ; 38(6): 875-8, 2013 Mar.
Artigo em Zh | MEDLINE | ID: mdl-23717971

RESUMO

OBJECTIVE: To investigate the intervention effect of aqueous fractions from Boschniakia rossica (BRAF) on hepatic oxidative stress in mice with liver injury induced by carbon tetrachloride (CCl4). METHOD: The experimental mice were randomly assigned into the normal control group, the model group, the silymarin (positive control) group, as well as high and low dose BRAF groups. Mice were treated intragastrically with silymarin or BRAF once every day for 7 days. At the end of the experiment, CCl4 was injected intraperitoneally into the mice to establish the acute liver injury model. The pathological changes was detected with hematoxylin and eosin (HE) staining, and the activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), superoxide dismutase (SOD) , catalase (CAT), glutathione peroxidase (GPx), Na+ -K+ -ATPase, Ca2+ -Mg2+ -ATPase, and the contents of reduced glutathione (GSH) and malondialdehyde (MDA) were detected by the colorimetric method. RESULT: BRAF significantly reduced ALT, AST and ALP activities in serum, alleviated hepatic injury induced by CCl4, increased SOD, CAT, GPx and GSH levels in liver, and SOD, Na + -K + -ATPase and Ca2+ -Mg2 + -ATPase activities in liver mitochondria, and decreased the MDA content in liver and liver mitochondria. CONCLUSION: BRAF reduces hepatic oxidative stress in mice with acute liver injury induced by CCl4, thereby showing the protective effect on mice with acute liver injury induced by CCl4.


Assuntos
Tetracloreto de Carbono/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Fígado/efeitos dos fármacos , Orobanchaceae/química , Estresse Oxidativo/efeitos dos fármacos , Água/química , Animais , Doença Hepática Induzida por Substâncias e Drogas/enzimologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Medicamentos de Ervas Chinesas/química , Fígado/enzimologia , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Solubilidade
11.
Mar Pollut Bull ; 188: 114668, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36736262

RESUMO

Cladophora glomerata (C. glomerata) is a typical macroalgae inducing green tide and affecting economic benefits in aquaculture. A high-efficiency, environment friendly compound essential oils (CEOs) was provided to control C. glomerata blooms. The inhibition effect of CEOs against C. glomerata was assessed through the growth, cellular morphology and the physiological and biochemical indexes of C. glomerata. Results of the Chl-a content indicated that 300 µL/L CEOs could significantly inhibited the growth (85 % ± 2 %) of C. glomerata on the 11th day; the damage degree of algal thallus can be observed based on the results of cell morphology; the results of the physiological and biochemical indicators presented the decreased photosynthetic capacity, the dysfunction of antioxidant system and the algal apoptosis gene caspase- 8, 9, 3 activated when C. glomerata exposed to CEOs. This study elucidated the effect and mechanism of CEOs control the green tide induced by C. glomerata.


Assuntos
Clorófitas , Óleos Voláteis , Alga Marinha , Óleos Voláteis/farmacologia , Clorófitas/química , Antioxidantes , Fotossíntese
12.
J Hepatocell Carcinoma ; 10: 1009-1017, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37405321

RESUMO

Background: TACE and TACE with or without targeted immunotherapy are crucial comprehensive therapies for middle and advanced HCC. However, a reasonable and concise score is needed to evaluate TACE and TACE combined with systemic therapy in HCC treatment. Methods: The HCC patients were grouped into two groups: training group (n = 778) (treated with TACE) and verification group (n = 333). The predictive value of baseline variables on overall survival was analyzed using COX model, and easy-to-use ALR (AST and Lym-R) scores. The best cut-off value of AST and Lym-R were determined using X-Tile software based on total survival time (OS) and further verified via a restricted three-spline method. Meanwhile, the score was further verified using two independent valid sets: TACE combined with targeted therapy and TACE with targeted combined immunotherapy. Results: In multivariate analysis, baseline serum AST>57.1 (p < 0.001) and Lym-R≤21.7 (p < 0.001) were identified as independent prognostic factors. The OS of patients in the TACE pooled cohort with 0, 1, and 2 scores were 28.1 (95% CI 24-33.8) months, 15 (95% CI 12.4-18.6) months, and 7.4 (95% CI 5.7-9.1) months, respectively. The time-varying ROC curve based on ALR showed that the AUC values for predicting 1, -2-and 3-year OS were 0.698, 0.718, and 0.636, respectively. These results are confirmed in two independent valid sets of TACE combined with targeted therapy and TACE with targeted combined immunotherapy. And we established a nomogram after COX regression to predict the 1 -, 2- and 3-year survival time. Conclusion: Our study confirmed that ALR score can predict the prognosis of HCC treated with TACE or TACE combined with systemic therapy.

13.
J Cancer Res Clin Oncol ; 149(15): 14271-14282, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37561208

RESUMO

INTRODUCTION: The aim of this study was to investigate the role of thymidine kinase 1 (TK1) levels in hepatocellular carcinoma (HCC) prognosis and to develop a nomogram for predicting HCC prognosis. METHOD: In this study, 1066 HCC patients were enrolled between August 2018 and April 2022. TK1 levels were measured within one week before enrollment, and the relationship with HCC prognosis was evaluated. Next, all patients were randomly assigned to the training set (70%, n = 746) and the validation set (30%, n = 320). We used multivariate Cox analysis to find independent prognostic factors in the training set to construct a nomogram. The predictive power of the nomogram was assessed using receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA). The optimal critical value of TK1 was determined as 2.35 U/L using X-tile software. RESULT: Before and after propensity score matching (PSM), the median overall survival (mOS) of the low-TK1 group (< 2.35 U/L) remained significantly longer than that of the high-TK1 group (≥ 2.35 U/L) (48.1 vs 16.5 months, p < 0.001; 75.7 vs 19.8 months, p = 0.001). Moreover, multivariate Cox analysis showed that the low TK1 level was an independent positive prognostic indicator. Additionally, the area under the ROC curve for predicting the 1-year, 2-year, and 3-year survival rates was 0.770, 0.758, and 0.805, respectively. CONCLUSIONS: TK1 could serve as a prognostic marker for HCC. In addition, the nomogram showed good predictive capability for HCC prognosis.

14.
Int J Parasitol Parasites Wildl ; 18: 249-259, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35800109

RESUMO

Platygaster robiniae is economically important as a highly specific parasitoid of the invasive pest Obolodiplosis robiniae which was introduced into the Euro-Asia region in the last decade. Despite being a critical and specific parasitoid of the invasive pest O. robiniae and its use as an effective biocontrol agent, the absence of sequence information from P. robiniae have limited its genetic applications for pest management in forests. Mitochondrial (mt) genomes generally contain abundant nucleotide information and thus are helpful for understanding species history. Here, we sequenced the complete mt genome of P. robiniae using next generation sequencing, and annotated 13 protein-coding, 22 tRNA, and 2 rRNA genes and a 702 bp noncoding region. Comparative analysis indicated that this mt genome has a normal A + T content and codons use, however possessed both the expected and unique rearrangements. Ten tRNAs at four gene blocks COII-ATP8, COIII-ND3, ND3-ND5 and the A + T-rich region-ND2 were rearranged, including gene shuffles, transpositions and inversions. Notably, two genes tRNA Ser(UCN) and tRNA Leu(CUN) had undergone long-range inversions, which is the first record of this rearrangement type in the superfamily Platygastroidea. The D-loops of both tRNA Ile and tRNA Leu(CUN) were absent from the tRNA secondary structure, which has not been reported from hymenopteran previously. Phylogenetic analysis based with the maximum likelihood and Bayesian methods showed that P. robiniae grouped with other species of Platygastridae, and that the superfamily Platygastridea is sister to the other Proctotrupomorpha superfamilies. Our tree strongly supports the monophyly of the five superfamilies of Proctotrupomorpha. This study discovered some unique characters of P. robiniae, and contributes to our understanding of genome rearrangements in the order Hymenoptera.

15.
Nanoscale ; 13(35): 14705-14712, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34533166

RESUMO

Three-dimensional catalysts have attracted great attention in the field of the hydrogen evolution reaction (HER).However, great challenges remain in structural innovation and performance enhancement. Herein we designed and tailored a unique three-dimensional cross-linked neural network-like CoP-based composite, that is, carbon nanofibers inserted in CoP/NC polyhedra derived from in situ self-assembled bacterial cellulose (BC) wired ZIF-67 polyhedra via high-temperature carbonization and subsequent phosphorization. The obtained integrated catalyst (3-D CNF@CoP/NC) consists of CoP/NC polyhedra with abundant active sites as the "neurons" and carbon nanofibers as the "axons", and displayed remarkable activity with an overpotential of 64.5 mV and 105.6 mV at 10 mA cm-2 in 0.5 M H2SO4 and 1 M KOH respectively and good stability with negligible current change after 80 h of chronoamperometric measurement or 4000 CV cycles. This work offers a high-performance HER catalyst and paves a new way for the rational engineering of unique 3-D interconnected hierarchical porous networks featuring ultrafast charge transfer and mass transport.

16.
ACS Appl Mater Interfaces ; 13(34): 40942-40952, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34415735

RESUMO

Designing metal sulfides with unique configurations and exploring their electrochemical activities for hydrogen peroxide (H2O2) and hydrazine (N2H4) is challenging and desirable for various fields. Herein, hollow microflower-like CuS@C hybrids were successfully assembled and further exploited as a versatile electrochemical sensing platform for H2O2 reduction and N2H4 oxidation, of which the elaborate strategies make the perfect formation of hollow architecture, providing considerable electrocatalytic sites and fast charge transfer rate, while the appropriate introduction polydopamine-derived carbon skeleton facilitates the electronic conductivity and boosts structural robustness, thus generating wide linear range (0.05-14 and 0.01-10 mM), low detection limit (0.22 µM and 0.07 µM), and a rather low overpotential (-0.15 and -0.05 V) toward H2O2 and N2H4, as well as good selectivity, excellent reproducibility, and admirable long-term stability. It should be highlighted that the operating potentials can compare favorably with those of some reported H2O2 and N2H4 sensors based on noble metals. In addition, good recoveries and acceptable relative standard deviations (RSDs) attained in serum and water samples fully verify the accuracy and anti-interference capability of our proposed sensor systems. These results not only elucidate an effective structural nanoengineering strategy for electroanalytical science but also advance the rational utilization of H2O2 and N2H4 in practicability.

17.
Front Res Metr Anal ; 5: 577131, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33870050

RESUMO

A Sleeping Beauty is a publication that is apparently unrecognized by citation for some period of time before experiencing a burst of recognition. Various reasons, including resistance to new ideas, have been attributed to such delayed recognition. We study this phenomenon in the special case of co-citations, which represent new ideas generated through the combination of existing ones. Using relatively stringent selection criteria derived from the work of others, we analyze a very large dataset of over 940 million unique co-cited article pairs, and identify 1,196 cases of delayed co-citations. We further classify these 1,196 cases with respect to amplitude, rate of citation, and disciplinary origin.

18.
Nanoscale ; 12(43): 22161-22172, 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33135720

RESUMO

Metal chalcogenides with structural pulverization/degradation and intrinsic low electrical conductivity trigger the challenging issues of serious capacity fading and inferior rate capability upon repeated de-/sodiation cycling. Multiple electroactive heterostructures can integrate the inherent advantages of a strong synergistic coupling effect to improve their electrochemical Na+-storage behavior and structural durability, showing robust mechanical features, fast Na+ immigration and abundant active insertion sites at intriguing heterointerfaces. Hence, a series-wound architecture of metal-organic framework (MOF)-derived heterogeneous (CoFe)Se2 hollow nanocubes confined into a one-dimension carbon nanofiber skeleton ((CoFe)Se2@CNS) was successfully developed via a template-assisted liquid phase anion exchange followed by electrospinning and conventional selenization treatment. When examined as an anode for sodium ion batteries, the (CoFe)Se2@CNS electrode exhibits remarkably enhanced electrochemical Na+-storage performance delivering a high sodiation capacity as high as 213.9 mA h g-1 after 3650 cycles at 5 A g-1 with a capacity degradation rate of only 0.0047% per cycle; specifically, it shows tremendous rate performance and ultrastable cycling durability of 194.7 mA h g-1 at a high rate of 8 A g-1 after 5630 cycles. This work can shed light on a fundamental approach for designing heterostructures of multiple electroactive components toward high-performance alkali metal ion batteries.

19.
J Phys Condens Matter ; 31(46): 465002, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31425148

RESUMO

Photocatalytic water-splitting for hydrogen generation is a promising way to solve the energy crisis, yet the design of efficient photocatalysts is still a challenge. By utilization of first principles calculations, we predict the photocatalytic properties of monolayer boron phosphide (BP) based BP/XY2 (X = Mo, W; Y = S, Se) composites of different rotated configurations. Our results suggest that the BP/XY2 composites can be stably formed, and the narrowed bandgaps ensure these composites are suitable for absorbing visible light. The bandgaps and band edge positions are slightly affected by the rotation angles. The BP/MoS2, BP/MoSe2, and BP/WSe2 are type II heterostructures. Furthermore, the transferred charge from BP to XY2 layers leads to the formation of electric fields, which efficiently separate the photoinduced carriers. The band alignments of BP/MoS2, BP/MoS2, BP/MoSe2, and BP/WSe2 satisfy the requirements of overall water-splitting within the pH scope of 3.6-7.9, 6.8-7.9, 4.0-8.0, and 8.7-8.8. This work will provide valuable insight for designing efficient water-splitting photocatalysts.

20.
Nanoscale Res Lett ; 14(1): 121, 2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30941603

RESUMO

Bi3.15Nd0.85Ti2.99Mn0.01O12 (BNTM) thin films with (200)-orientations, (117)-orientations, and mixed-orientations were prepared by sol-gel methods. The influence of orientations on polarization fatigue behaviors of BNTM thin films were systematically investigated at both low and elevated temperatures. It was found that the changed trends of the polarization fatigue of (200)-oriented and (117)-oriented BNTM thin films at elevated temperatures were opposite. The fatigue properties become exacerbated for the (200)-oriented ones and become improved for the (117)-oriented ones, while the reduction of remanent polarization first decreases and then increases for the mixed-oriented ones. It can be assumed that the different roles played by domain walls and interface layer with increasing T in these thin films have caused such differences, which was certified by the lower activation energies (0.12-0.13 eV) of (200)-oriented BNTM thin films compared to those of BNTM thin films (0.17-0.31 eV) with other orientations through the temperature-dependent impedance spectra analysis. With the aid of piezoresponse force microscopy (PFM), the non-neutral tail-to-tail or head-to-head polarization configurations with greater probabilities for (117)-oriented and mixed-oriented thin films were found, while a majority of the neutral head-to-tail polarization configurations can be observed for (200)-oriented ones.

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