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1.
Langmuir ; 40(28): 14291-14302, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38950193

RESUMO

The key to enhancing water electrolysis efficiency lies in selecting highly efficient catalysts. Currently, high-entropy alloys (HEAs) are utilized in electrocatalysis applications owing to their diverse elemental composition, disordered elemental distribution, and the high solubility of each element, endowing them with excellent catalytic performance. The experiments were conducted using isoatomic FeNiCrMo HEA as a precursor, with a high-activity three-dimensional nanoporous structure rapidly synthesized via electrochemical one-step dealloying in a choline chloride-thiourea (ChCl-TU) deep eutectic solvent (DES). The results indicate that the dealloyed Fe20Co20Ni20Cr20Mo20 HEA mainly consists of two phases: face-centered cubic and σ phases. The imbalance in the distribution of elements in these two phases leads to quite different corrosion speeds with the FCC phase being preferentially corroded. Furthermore, synergistic electron coupling between surface atoms in the three-dimensional nanoporous structure strengthens the behavior of the oxygen evolution reaction (OER). At a current density of 40 mA cm-2, the overpotential after dealloying decreased to 370 mV, demonstrating excellent stability. The technique demonstrated in this work provides a novel approach to improve the catalytic activity of OER.

2.
Materials (Basel) ; 16(16)2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37629934

RESUMO

Airport pavements are prone to early defects during the construction phase, and their early performance during the construction phase is significantly affected by the external temperature field. This article takes the concrete pavement of Xiamen Xiang'an New Airport as an example and uses a three-dimensional (3D) humidity simulation program for cement concrete pavement to study the evolution behavior of the early stage humidity field of the pavement in a humid and hot climate environment. The results indicate that the evolution law of the humidity field of the concrete pavement slab was consistent with the environmental field, presenting a 24 h periodic variation. The environmental field had a significant impact on the humidity of the surface layer of the pavement slab, and the humidity decreased rapidly with time. There was a humidity gradient on both the horizontal plane and the cutting plane of the slab, the horizontal humidity was concentrated from the boundary into the middle of the slab, and the sectional humidity was concentrated from the top to the bottom of the slab. Environmental parameters, construction parameters, and material and structural parameters all influenced humidity through humidity exchange or by changing the saturated vapor pressure inside the slab. The humidity field was most sensitive to environmental humidity and maintenance methods, but less sensitive to material parameters and structural parameters. Through analysis, it is advisable to avoid hot seasons, choose periods of increased environmental humidity, adopt appropriate maintenance methods during construction to reduce humidity stress on the slab, and therefore decrease early stage deterioration and improve service life.

3.
Heliyon ; 9(6): e16870, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37346322

RESUMO

Background: Prostate cancer (PCa) is among the most generally diagnosed cancers in males. A long non-coding RNA (lncRNA) called AC245100.4 has been discovered and linked to PCa carcinogenesis. However, its specific and potential mechanism is uncertain in PCa. In this research, we investigated the role of AC245100.4 in cell proliferation and the underlying mechanism in PCa cells. Methods: qRT-PCR assays were utilized to detect AC245100.4 expression and confirm its downstream target. The pathways related to AC245100.4 were identified by RAP-MS. PCa cell proliferation was experimented by Cell Counting Kit-8 and Colony formation assays. Western blot was performed to detect PAR2, AKT, p-AKT, Cyclin D1 and PCNA expression. Results: AC245100.4/PAR2 overexpression promotes PCa cell proliferation and the opposite results are obtained after AC245100.4/PAR2 knockdown. Mechanistically, we found that PAR2 is confirmed as the AC245100.4 downstream target and AC245100.4 promotes PCa cell proliferation by regulating PAR2. AC245100.4 promotes PCa cell proliferation via PI3K/AKT pathway. Rescue assays validated that PAR2 knockdown reversed the impact of AC245100.4 overexpression on increasing p-AKT protein levels. Conclusion: This research revealed that AC245100.4 enhances cell proliferation in PCa cells through modulating the PAR2/PI3K/AKT axis, which may offer novel tumor markers and potential therapeutic targets for PCa.

4.
Materials (Basel) ; 14(15)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34361393

RESUMO

SBS-modified bitumen (SMB) is susceptible to aging, which seriously influences its service performance and life. In order to strengthen the anti-aging ability of SMB, triethoxyvinylsilane was designed to organically modify layered double hydroxides (LDHs) and was applied to modify SMB. The dispersibility and storage stability of LDHs in SMB were markedly enhanced after triethoxyvinylsilane organic modification, and the compatibility and storage stability of SBS in bitumen were simultaneously enhanced. Compared with SMB, the introduction of LDHs and organic LDHs (OLDHs) could ameliorate the high-temperature properties of SMB, and the thermostability of SBS in bitumen at a high temperature was also distinctly improved, especially OLDHs. After aging, due to the oxidation of molecular bitumen and the degradation of molecular SBS, SMB became hardened and brittle, and the rheological properties were significantly deteriorated, which had serious impacts on the performance of SMB. LDHs can mitigate the detriment of aging to bitumen and SBS, and the deterioration of the rheological properties of SMB is obviously alleviated. As a result of the better dispersibility and storage stability, OLDHs exerted superior reinforcement of the anti-aging ability of SMB.

5.
Sci Prog ; 104(2): 368504211026284, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34143701

RESUMO

Aiming at the problem of bus voltage control in DC microgrid, a dynamic compensation control strategy based on a residual generator is designed to complete the voltage compensation of DC-DC converter. Firstly, based on the DC microgrid system architecture, the bus voltage fluctuations are analyzed theoretically, and then the DC-DC converter state-space mathematical models of the DC microgrid system are established to obtain the input-output relationship of the control system. Based on the theory of double coprime decomposition and Youla parameterization stable controller, the proposed control architecture based on the residual generator is obtained, and the output value generated by the current disturbance is compensated in reverse by applying model matching theory. The voltage loop compensation controller Q(s) is obtained by the linear matrix inequality method (LMI), and the current loop compensation controller H(s) is designed according to the dynamic structure diagram of the DC-DC converter. Hardware-in-the-loop simulation (HILS) results show that the architecture can improve the dynamic performance of the DC-DC converter without changing the original system structure parameters, and suppress the DC bus voltage fluctuations caused by load switching, power fluctuations, and AC-side load imbalances, and enhance the robustness of the system.

6.
RSC Adv ; 11(36): 22131-22139, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35480833

RESUMO

To improve the anti-aging ability of SBS modified bitumen (SMB), layered double hydroxide (LDH) organically modified by hexadecyltrimethoxysilane was prepared and utilized for the modification of SMB. According to X-ray photoelectron spectroscopy, hexadecyltrimethoxysilane has been grafted into LDH through chemical bonding. Compared with LDH, the hydrophilicity of organic LDH (OLDH) was obviously reduced, and OLDH possessed better dispersibility and stability in SMB, because of the decrease of hydroxyl and the introduced organo-functional groups on the surface of LDH. The addition of OLDH and LDH can ameliorate the high temperature behavior of SMB, especially OLDH. After aging, bitumen was oxidized and SBS was degraded, which resulted in the physical and rheological property deterioration of SMB. LDH can alleviate the destruction of aging on the performance and chemical structure of SMB. Furthermore, the improvement of LDH on the anti-aging ability of SMB has been further enhanced after hexadecyltrimethoxysilane organic modification.

7.
Neuroscience ; 417: 57-69, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31404586

RESUMO

An increasing number of studies have demonstrated the benefits of young individual-derived blood for aging-related diseases. However, the effects of young blood on the cognitive and cholinergic transmission defects in aging-associated Alzheimer's disease (AD) remain elusive. In the current study, we showed that young blood serum delivered intravenously attenuated deficits in hippocampal-dependent learning and memory, alleviated hippocampal Aß plaque pathology, restored synapse formation and synaptic plasticity, repaired the hippocampal cholinergic circuit, and triggered several canonical neuroprotective mechanisms [including repressor element 1-silencing transcription factor (REST)/Forkhead box protein O1 (FOXO1) signaling] in aged AD model mice. However, pharmacological blockage of hippocampal cholinergic activity nearly abrogated the neuroprotective actions of young blood serum in AD mice. Thus, our findings suggest that exogenous young blood serum exerts therapeutic effects on AD-associated cognitive disorders and pathology by promoting hippocampal cholinergic input and simultaneously activating other neuroprotective mechanisms.


Assuntos
Envelhecimento/metabolismo , Doença de Alzheimer/terapia , Transfusão de Sangue , Neurônios Colinérgicos/metabolismo , Hipocampo/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Animais , Hipocampo/fisiopatologia , Aprendizagem , Masculino , Memória , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Soro
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