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1.
J Am Chem Soc ; 146(32): 22335-22347, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39092859

RESUMO

Searching for high energy-density electrode materials for sodium ion batteries has revealed Na-deficient intercalation compounds with lattice oxygen redox as promising high-capacity cathodes. However, anionic redox reactions commonly encountered poor electrochemical reversibility and unfavorable structural transformations during dynamic (de)sodiation processes. To address this issue, we employed lithium orbital hybridization chemistry to create Na-O-Li configuration in a prototype P2-layered Na43/60Li1/20Mg7/60Cu1/6Mn2/3O2 (P2-NaLMCM') cathode material. That Li+ ions, having low electronegativity, reside in the transition metal slabs serves to stimulate unhybridized O 2p orbitals to facilitate the stable capacity contribution of oxygen redox at high state of charge. The prismatic-type structure evolving to an intergrowth structure of the Z phase at high charging state could be simultaneously alleviated by reducing the electrostatic repulsion of O-O layers. As a consequence, P2-NaLMCM' delivers a high specific capacity of 183.8 mAh g-1 at 0.05 C and good cycling stability with a capacity retention of 80.2% over 200 cycles within the voltage range of 2.0-4.5 V. Our findings provide new insights into both tailoring oxygen redox chemistry and stabilizing dynamic structural evolution for high-energy battery cathode materials.

3.
Artigo em Inglês | MEDLINE | ID: mdl-39046653

RESUMO

Endothelial-to-mesenchymal transition (EndoMT) is associated with neointimal hyperplasia and vein graft failure, and heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1) has emerged as a major modulator of EMT. We aimed to investigate the functional consequence of EndoMT in neointimal hyperplasia and the precise role of hnRNPA1 in the regulation of EndoMT and neointimal hyperplasia. We investigated the spatial and temporal distribution characteristics of EndoMT cells in a mouse model of vein graft transplantation. In vitro, we studied the interaction between EndoMT cells and VSMCs, and the underlying mechanism was investigated by cytokine antibody assays. In cultured HUVECs, we studied the effect of hnRNPA1 on EndoMT and the cellular interactions by using siRNA-mediated knockdown and adenovirus-mediated overexpression. We further investigated the role of hnRNPA1 in EndoMT and neointimal hyperplasia in vivo with an AAV-mediated EC-specific hnRNPA1 overexpression murine model. We demonstrated the presence of EndoMT cells during the initial stage of neointimal formation, and that EndoMT cells promoted the proliferation and migration of VSMCs in vitro. Mechanistic studies revealed that EndoMT cells express and secrete a higher level of PDGF-B. Furthermore, we found a regulatory role for hnRNPA1 in EndoMT in vitro and in vivo. Similarly, we found that hnRNPA1 overexpression in ECs reduced the expression and secretion of PDGF-B during EndoMT, effectively inhibiting EndoMT cell-mediated activation of VSMCs in vitro and neointimal formation in vivo. Taken together, these findings indicate that EndoMT cells can activate VSMCs through a paracrine mechanism mediated by hnRNPA1 and lead to neointimal hyperplasia.

4.
J Colloid Interface Sci ; 671: 653-663, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38820849

RESUMO

The application of Li-S batteries on large scale is held back by the sluggish sulfur kinetics and low synthesis efficiency of sulfur host. In addition, the preparation of catalysts that promote polysulfide redox kinetics is complex and time-consuming, reducing the cost of raw materials in Li-S. Here, a universal synthetic strategy for rapid fabrication of sulfur cathode and metal compounds nanocatalysts is reported based on microwave heating of graphene. Heat-sensitive materials can achieve rapid heating due to graphene reaching 500 ℃ within 4 s via microwave irradiation. The MoP-MoS2/rGO catalyst demonstrated in this work was synthesized within 60 s. When used for catalysts for Li-S batteries whose graphene/sulfur cathodes were also synthesized by microwave heating, enhanced catalytic effect for sulfur redox reaction was verified via experimental and DFT theoretical results. Benefiting from fast redox reaction (MoP), smooth Li+ diffusion pathways (MoS2), and large conductive network (rGO), the assembled Li-S battery with MoP-MoS2/rGO-Add@CS displays a remarkable initial specific capacity, stable lithium anode and good cycle stability (in pouch cells) using this two-pronged strategy. The work provides a practical strategy for advanced Li-S batteries toward a wide range of applications.

5.
Nat Commun ; 15(1): 2234, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472180

RESUMO

Coherent spin waves possess immense potential in wave-based information computation, storage, and transmission with high fidelity and ultra-low energy consumption. However, despite their seminal importance for magnonic devices, there is a paucity of both structural prototypes and theoretical frameworks that regulate the spin current transmission and magnon hybridization mediated by coherent spin waves. Here, we demonstrate reconfigurable coherent spin current transmission, as well as magnon-magnon coupling, in a hybrid ferrimagnetic heterostructure comprising epitaxial Gd3Fe5O12 and Y3Fe5O12 insulators. By adjusting the compensated moment in Gd3Fe5O12, magnon-magnon coupling was achieved and engineered with pronounced anticrossings between two Kittel modes, accompanied by divergent dissipative coupling approaching the magnetic compensation temperature of Gd3Fe5O12 (TM,GdIG), which were modeled by coherent spin pumping. Remarkably, we further identified, both experimentally and theoretically, a drastic variation in the coherent spin wave-mediated spin current across TM,GdIG, which manifested as a strong dependence on the relative alignment of magnetic moments. Our findings provide significant fundamental insight into the reconfiguration of coherent spin waves and offer a new route towards constructing artificial magnonic architectures.

6.
Nanoscale ; 16(15): 7645-7659, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38529611

RESUMO

The presence of strong anharmonic effects in surface functionalized MXenes greatly challenges the use of harmonic lattice dynamics calculations to predict their phonon spectra and lattice thermal conductivity at finite temperatures. Herein, we demonstrate the workflow for training and validating machine learning potentials in terms of moment tensor potential (MTP) for MXenes including Mo2TiC2, Mo2TiC2O2, Mo2TiC2F2 and Janus-Mo2TiC2OF monolayers. Then, the MTPs of MXenes are successfully combined with the harmonic lattice dynamics calculations to obtain the temperature renormalized phonon spectra, three-phonon scattering rates, phonon relaxation times and lattice thermal conductivity at finite temperatures. Furthermore, combining MTPs with classic molecular dynamics simulations at finite temperatures directly enables the calculation of phonon quasi-particle spectral energy density with a full inclusion of all anharmonic effects in MXenes. Our current results indicate that anharmonic effects are found to be relatively weak in Mo2TiC2 and Mo2TiC2O2 monolayers, whereas the phonon quasi-particle spectral energy densities largely resemble those of harmonic or renormalized lattice dynamics calculations. Significant broadening of spectral energy density at finite temperature is predicted for Mo2TiC2F2 and Janus-Mo2TiC2OF monolayers, implying strong anharmonic effects in those MXenes. Our work paves a new way for fast and reliable calculation of the phonon scattering process and lattice thermal conductivity of MXenes within MTPs trained from first-principles molecular dynamics simulations in the future.

7.
Angew Chem Int Ed Engl ; 63(15): e202400172, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38345140

RESUMO

A negatively curved aza-nanographene (NG) containing two octagons was synthesized by a regioselective and stepwise cyclodehydrogenation procedure, in which a double aza[7]helicene was simultaneously formed as an intermediate. Their saddle-shaped structures with negative curvature were unambiguously confirmed by X-ray crystallography, thereby enabling the exploration of the structure-property relationship by photophysical, electrochemical and conformational studies. Moreover, the assembly of the octagon-embedded aza-NG with fullerenes was probed by fluorescence spectral titration, with record-high binding constants (Ka=9.5×103 M-1 with C60, Ka=3.7×104 M-1 with C70) found among reported negatively curved polycyclic aromatic compounds. The tight association of aza-NG with C60 was further elucidated by X-ray diffraction analysis of their co-crystal, which showed the formation of a 1 : 1 complex with substantial concave-convex interactions.

8.
Nano Lett ; 24(10): 3125-3132, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38421805

RESUMO

Dilute magnetic semiconductors (DMSs) have attracted much attention because of their potential use in spintronic devices. Here, we demonstrate the observation of robust ferromagnetism in a solution-processable halide perovskite semiconductor with dilute magnetic ions. By codoping of magnetic (Fe2+) and aliovalent (Bi3+) metal ions into CH3NH3PbCl3 (MAPbCl3) perovskite, ferromagnetism with well-saturated magnetic hysteresis loops and a maximum coercivity field of 1280 Oe was observed below 12 K. The ferromagnetic resonance measurements revealed that the incorporation of aliovalent ions modulates the carrier concentration and plays an essential role in realizing the ferromagnetism in dilute magnetic halide perovskites. Magnetic ions are proposed to interact through itinerant charge carriers to achieve ferromagnetic coupling. Our work provides a new avenue for the development of solution-processable magnetic semiconductors.

9.
China CDC Wkly ; 6(7): 109-117, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38405602

RESUMO

What is already known about this topic?: Approximately 50% of patients with mpox are human immunodeficiency virus (HIV)-infected globally. Studies have shown that individuals with advanced HIV infection tend to have more severe clinical manifestations and higher mortality rates after mpox infection. What is added by this report?: The study revealed that individuals living with HIV have a low level of Knowledge, Attitude, and Practice (KAP) towards mpox. Several factors, including age, registered residence, sexual orientation, education level, viral load, and co-occurrence of other sexually transmitted diseases, were found to influence the KAP towards mpox. What are the implications for public health practice?: This study is the first to investigate the KAP of mpox among individuals living with HIV. The findings suggest that mpox health education should prioritize individuals with co-existing sexually transmitted diseases (STDs) and a high viral load.

10.
J Cardiovasc Transl Res ; 17(2): 287-297, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38196010

RESUMO

Blood pressure dipping patterns have long been considered to be associated with adverse events. We aimed to investigate whether dipping patterns of postoperative MAP were related to 90-day and hospital mortality in patients undergoing CABG. Four thousand three hundred ninety-one patients were classified into extreme dippers (night-to-day ratio of MAP ≤ 0.8), dippers (0.8 < night-to-day ratio of MAP ≤ 0.9), non-dippers (0.9 < night-to-day ratio of MAP ≤ 1), and reverse dippers (> 1). Compared with non-dippers, reverse dippers were at a higher risk of 90-day mortality (aHR = 1.58; 95% CI, 1.10-2.27) and hospital mortality (aOR = 1.97; 95% CI, 1.12-3.47). A significant interaction was observed between hypertension and dipping patterns (P for interaction = 0.02), with a significant increased risk of 90-day mortality in non-hypertensive reverse dippers (aHR = 1.90; 95% CI, 1.17-3.07) but not in hypertensive reverse dippers (aHR = 1.26; 95% CI, 0.73-2.19).


Assuntos
Pressão Arterial , Ritmo Circadiano , Ponte de Artéria Coronária , Doença da Artéria Coronariana , Mortalidade Hospitalar , Hipertensão , Humanos , Ponte de Artéria Coronária/mortalidade , Ponte de Artéria Coronária/efeitos adversos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Fatores de Risco , Fatores de Tempo , Hipertensão/fisiopatologia , Hipertensão/mortalidade , Hipertensão/diagnóstico , Resultado do Tratamento , Doença da Artéria Coronariana/mortalidade , Doença da Artéria Coronariana/cirurgia , Doença da Artéria Coronariana/fisiopatologia , Estudos Retrospectivos , Medição de Risco , Monitorização Ambulatorial da Pressão Arterial
11.
J Chem Phys ; 160(2)2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38189614

RESUMO

The recent development of accurate and efficient semilocal density functionals on the third rung of Jacob's ladder of density functional theory, such as the revised regularized strongly constrained and appropriately normed (r2SCAN) density functional, could enable rapid and highly reliable prediction of the elasticity and temperature dependence of thermophysical parameters of refractory elements and their intermetallic compounds using the quasi-harmonic approximation (QHA). Here, we present a comparative evaluation of equilibrium cell volumes, cohesive energy, mechanical moduli, and thermophysical properties (Debye temperature and thermal expansion coefficient) for 22 transition metals using semilocal density functionals, including the local density approximation (LDA), Perdew-Burke-Ernzerhof (PBE) and PBEsol generalized gradient approximations (GGAs), and the r2SCAN meta-GGA. PBEsol and r2SCAN deliver the same level of accuracies for structural, mechanical, and thermophysical properties. PBE and r2SCAN perform better than LDA and PBEsol for calculating cohesive energies of transition metals. Among the tested density functionals, r2SCAN provides an overall well-balanced performance for reliably computing cell volumes, cohesive energies, mechanical properties, and thermophysical properties of various 3d, 4d, and 5d transition metals using QHA. Therefore, we recommend that r2SCAN could be employed as a workhorse method to evaluate thermophysical properties of transition metal compounds and alloys in high throughput workflows.

12.
Phys Chem Chem Phys ; 26(2): 1406-1427, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38112095

RESUMO

First-principles calculations were performed to analyze the atomic structures and electrochemical energy storage properties of novel MoS2⊥boridene heterostructures by anchoring MoS2 nanoflakes on Mo4/3B2 and Mo4/3B2O2 monolayers. Both thermodynamic and thermal stabilities of each heterostructure were thoroughly evaluated from the obtained binding energies and through first-principles molecular dynamics simulations at room temperature, confirming the high formability of the heterostructures. The electrochemical properties of MoS2⊥Mo4/3B2 and MoS2⊥Mo4/3B2O2 heterostructures were investigated for their potential use as anodes for alkaline metal ion batteries (Li+, Na+ and K+). It was revealed that Li+ and Na+ can form multiple stable full adsorption layers on both heterostructures, while K+ forms only a single full adsorption layer. The presence of a negative electron cloud (NEC) contributes to the stabilization of a multi-layer adsorption mechanism. For all investigated alkaline metal ions, the predicted ion diffusion dynamics are relatively sluggish for the adsorbates in the first full adsorption layer on MoS2⊥boridene heterostructures due the relatively large migration energies (>0.50 eV), compared to those of second or third full adsorption layers (<0.30 eV). MoS2⊥Mo4/3B2O2 exhibited higher onset and mean open circuit voltages as anodes for alkaline metal-ion batteries than MoS2⊥Mo4/3B2 hybrids because of enhanced interactions between the adsorbate and the Mo4/3B2O2 monolayer with the presence of O-terminations. Tailoring the size and horizontal spacing between two neighboring MoS2 nano-flakes in heterostructures led to high theoretical capacities for LIBs (531 mA h g-1), SIBs (300 mA h g-1) and PIBs (131 mA h g-1) in the current study.

13.
Eur J Cardiothorac Surg ; 63(4)2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-37021931

RESUMO

OBJECTIVES: Whether the presence or evolution of right ventricular dysfunction (RVD) affects the prognosis and the therapeutic choice between coronary artery bypass grafting (CABG) or medical therapy alone in patients with ischaemic cardiomyopathy (ICM) remains unclear. We investigate the prognostic and therapeutic implications of RVD in patients with ICM. METHODS: Patients with baseline echocardiographic right ventricular (RV) assessment were included from the Surgical Treatment of Ischaemic Heart Failure trial. The primary outcome was all-cause mortality. RESULTS: Of 1212 patients enrolled in the Surgical Treatment of Ischaemic Heart Failure trial, 1042 patients were included, with 143 (13.7%) mild RVD and 142 (13.6%) moderate-to-severe RVD. After a median follow-up of 9.8 years, compared with patients with normal RV function, patients with RVD had a higher risk of mortality [mild RVD: adjusted hazard ratio (aHR) 1.32; 95% confidence interval (CI) 1.06-1.65; moderate-to-severe RVD: aHR, 1.75; 95% CI 1.40-2.19]. Among patients with moderate-to-severe RVD, CABG provided no additional survival benefits compared to medical therapy alone (aHR: 0.98; 95% CI: 0.67-1.43). Among 746 patients with pre- and post-therapeutic RV assessment, a gradient risk for death increased from patients with consistent normal RV function, to patients with recovery from RVD, new-onset RVD and persistent RVD. CONCLUSIONS: RVD was associated with a worse prognosis in patients with ICM, and CABG provided no additional survival benefits to patients with moderate-to-severe RVD. The evolution of RV function had important prognostic implications, which emphasized the importance of both pre- and post-therapeutic RV assessment.


Assuntos
Cardiomiopatias , Insuficiência Cardíaca , Isquemia Miocárdica , Disfunção Ventricular Direita , Humanos , Disfunção Ventricular Direita/etiologia , Disfunção Ventricular Direita/cirurgia , Ponte de Artéria Coronária/efeitos adversos , Ecocardiografia , Isquemia Miocárdica/complicações , Isquemia Miocárdica/cirurgia , Cardiomiopatias/complicações , Cardiomiopatias/cirurgia
14.
Adv Sci (Weinh) ; 10(16): e2207506, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36995070

RESUMO

Growing concentration on the novel information processing technology and low-cost, flexible materials make the spintronics and organic materials appealing for the future interdisciplinary investigations. Organic spintronics, in this context, has arisen and witnessed great advances during the past two decades owing to the continuous innovative exploitation of the charge-contained spin polarized current. Albeit with such inspiring facts, charge-absent spin angular momentum flow, namely pure spin currents (PSCs) are less probed in organic functional solids. In this review, the past exploring journey of PSC phenomenon in organic materials are retrospected, including non-magnetic semiconductors and molecular magnets. Starting with the basic concepts and the generation mechanism for PSC, the representative experimental observations of PSC in the organic-based networks are subsequently demonstrated and summarized, by accompanying explicit discussion over the propagating mechanism of net spin itself in the organic media. Finally, future perspectives on PSC in organic materials are illustrated mainly from the material point of view, including single molecule magnets, complexes for the organic ligands framework as well as the lanthanide metal complexes, organic radicals, and the emerging 2D organic magnets.

15.
Nat Commun ; 14(1): 840, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36792610

RESUMO

Multiferroic materials have great potential in non-volatile devices for low-power and ultra-high density information storage, owing to their unique characteristic of coexisting ferroelectric and ferromagnetic orders. The effective manipulation of their intrinsic anisotropy makes it promising to control multiple degrees of the storage "medium". Here, we have discovered intriguing in-plane electrical and magnetic anisotropies in van der Waals (vdW) multiferroic CuCrP2S6. The uniaxial anisotropies of current rectifications, magnetic properties and magnon modes are demonstrated and manipulated by electric direction/polarity, temperature variation and magnetic field. More important, we have discovered the spin-flop transition corresponding to specific resonance modes, and determined the anisotropy parameters by consistent model fittings and theoretical calculations. Our work provides in-depth investigation and quantitative analysis of electrical and magnetic anisotropies with the same easy axis in vdW multiferroics, which will stimulate potential device applications of artificial bionic synapses, multi-terminal spintronic chips and magnetoelectric devices.

16.
Food Chem ; 408: 135192, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36592546

RESUMO

Novel covalent organic frameworks (COFs) based PAN@TpBD(NH2)2 electrospun composite nanofiber membranes (ECNMs) were fabricated as strong anion exchange sorbent by implementing electrospinning technology. The finished sorbent was characterized, and key parameters of pipette-tip solid phase extraction (PTSPE) procedures were investigated. Inorganic arsenic (iAs) was successfully separated from rice under the optimal precondition conditions, and quantified by hydride generation-atomic fluorescence spectrometry (HG-AFS). This PTSPE-HG-AFS methodology achieved 0.015 µg L-1 detection limit, 4.67 % relative standard deviation, and 86.48~99.11 % recoveries. In this work, preparation and characterization of this novel COFs-based anion exchange sorbent, PAN@TpBD(NH2)2 ECNMs, is described and its suitability for PTSPE applications is demonstrated.


Assuntos
Arsênio , Estruturas Metalorgânicas , Nanofibras , Oryza , Estruturas Metalorgânicas/química , Arsênio/análise , Oryza/química , Nanofibras/química , Extração em Fase Sólida/métodos , Limite de Detecção
17.
Nanoscale ; 14(48): 17955-17975, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36377681

RESUMO

We conducted a comprehensive density functional theory investigation using the r2SCAN-rVV10 functional on the structural stability and electrochemical properties of boridenes for their use as anode materials in rechargeable alkaline (earth) metal-ion batteries (Li+, Na+, K+, Mg2+ and Ca2+). According to first-principles molecular dynamics simulations and reaction thermodynamic calculations, Mo4/3B2(OH)2 and Mo4/3B2F2 are unstable in the presence of alkaline (earth) metal ions due to the surface-conversion reactions between the surface terminations and adsorbates. Meanwhile, the bare Mo4/3B2 and Mo4/3B2O2 monolayers not only can accommodate alkaline (earth) metal ions, but also form stable multi-layer adsorption structures for most of the studied metal ions (Li+, Na+, K+, Mg2+ and Ca2+). The predicted gravimetric capacities of the bare Mo4/3B2 monolayer (Mo4/3B2O2) are 625.9 mA h g-1 (357.3 mA h g-1), 247.20 mA h g-1 (392.1 mA h g-1), 101.8 mA h g-1 (206.4 mA h g-1), 667.0 mA h g-1, and 413.0 mA h g-1 (485.4 mA h g-1) for Li+, Na+, K+, Mg2+ and Ca2+ ions, respectively. The bare Mo4/3B2 exhibits lower onset charging open circuit voltages for alkaline (earth) metal ions than that of Mo4/3B2O2. The diffusivities of the metal ions were revealed to be high on the boridene monolayer especially for the outer fully stable adsorption layers, where the migration energy barriers were found to be less than 0.10 eV. Similar to that of MXenes, the negative electron cloud (NEC) also plays a vital role in stabilizing the observed multi-layer adsorption structures for various metal ions on either the bare Mo4/3B2 or Mo4/3B2O2 monolayer.

18.
Chem Commun (Camb) ; 58(94): 13087-13090, 2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36341944

RESUMO

We present the synthesis and characterization of the first triple oxa[6]helicene with C3 symmetry. In contrast to the reported D3-symmetric triple oxa[7]helicene, the C3-symmetric analogue holds parallel electric and magnetic transition dipole moments and thus enhanced luminescence dissymmetry, shedding light on the critical role of molecular symmetry on chiroptical response.

19.
Chemistry ; 28(58): e202202243, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-35880725

RESUMO

We present here the synthesis and in-depth physicochemical characterization of a double hetero[7]helicene fused with four triazole rings at both helical ends. The comparison of this triazole-fused double helicene with the previously reported all-carbon and thiadiazole-fused analogs revealed the huge impact of the embedded aromatic rings on the photophysical features. The small structural variation of the terminal rings from thiadiazole to triazole caused a dramatic change of the photoluminescence quantum yields (PLQYs) from <1 % to 96 %, while the replacement of the terminal benzene rings with triazole rings induced a tenfold enhancement of the circularly polarized luminescence dissymmetry factor. These observations were well corroborated with transient absorption analysis and/or theoretic calculations. In addition, the triazole-fused double helicene exhibited ambipolar redox behavior, enabling the generation of radical cation and anion species by electrochemical and chemical methods and showing its potential for spin-related applications.

20.
Materials (Basel) ; 15(9)2022 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-35591406

RESUMO

At high temperatures, the insulation performance of polypropylene (PP) decreases, making it challenging to meet the application requirements of metallized film capacitors. In this paper, the dielectric performance of PP is improved by long-chain branching modification and adding different kinds of nucleating agents. The added nucleating agents are organic phosphate nucleating agent (NA-21), sorbitol nucleating agent (DMDBS), rare earth nucleating agent (WBG-Ⅱ) and acylamino nucleating agent (TMB-5). The results show that the long-chain branches promote heterogeneous nucleation and inhibit the motion of molecular chains, thereby enhancing the dielectric properties at high temperatures. Nucleating agents modulate the crystalline morphology of long-chain branched polypropylene (LCBPP), which leads to a decrease in the mean free path of carriers and an increase in trap energy level and trap density. Therefore, the conductivity is reduced and the breakdown strength is improved. Among the added nucleating agents, NA-21 showed a significant improvement in the electrical properties of LCBPP films. At 125 °C, compared with PP, the breakdown strength of the modified film is increased by 26.3%, and the energy density is increased by 66.1%. This method provides a reference for improving the dielectric properties of PP.

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