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1.
Small ; : e2402652, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38838056

RESUMEN

The optimization of metal-support interactions is used to fabricate noble metal-based nanoclusters with high activity for hydrogen evolution reaction (HER) in acid media. Specifically, the oxygen-defective Mn3O4 nanosheets supported Pt nanoclusters of ≈1.71 nm in diameter (Pt/V·-Mn3O4 NSs) are synthesized through the controlled solvothermal reaction. The Pt/V·-Mn3O4 NSs show a superior activity and excellent stability for the HER in the acidic media. They only require an overpotential of 19 mV to drive -10 mA cm-2 and show negligible activity loss at -10 and -250 mA cm-2 for >200 and >60 h, respectively. Their Pt mass activity is 12.4 times higher than that of the Pt/C and even higher than those of many single-atom based Pt catalysts. DFT calculations show that their high HER activity arises mainly from the strong metal-support interaction between Pt and Mn3O4. It can facilitate the charge transfer from Mn3O4 to Pt, optimizing the H adsorption on the catalyst surface and promoting the evolution of H2 through the Volmer-Tafel mechanism. The oxygen vacancies in the V·-Mn3O4 NSs are found to be inconducive to the high activity of the Pt/V·-Mn3O4 NSs, highlighting the great importance to reduce the vacancy levels in V·-Mn3O4 NSs.

2.
Small ; : e2406070, 2024 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-39128138

RESUMEN

This work reports a strategy that integrates the carbon nanotube (CNT) supporting, ultrathin carbon coating and oxygen defect generation to fabricate the RuO2 based catalysts toward the pH-universal hydrogen evolution reaction (HER) with high efficiencies. Specifically, the CNT supported RuO2 nanoparticles with ultrathin carbon loricae and rich oxygen vacancies at the surface (C@OV-RuO2/CNTs-325) have been synthesized. The C@OV-RuO2/CNTs-325 shows superior activities and excellent durability for the HER. It only requires overpotentials of 36.1, 18.0, and 19.3 mV to deliver -10 mA cm-2 in the acidic, neutral, and alkaline media, respectively. Its HER activities are comparable to that of the Pt/C in the acidic media but higher than those of the Pt/C in the neutral and alkaline media. The C@OV-RuO2/CNTs-325 shows excellent HER durability with no activity losses for > 500 h in the acidic, neutral or alkaline media at -250 mA cm-2. The density-functional-theory calculations indicate that the CNT supporting, the carbon coating, and the OVs can modulate the d-band centers of Ru, increasing the HER activities of C@OV-RuO2/CNTs-325, and stabilize the Ru atoms in the catalyst, increasing the durability of the C@OV-RuO2/CNTs-325. More interestingly, the C@OV-RuO2/CNTs-325 shows great potential for practical applications toward overall seawater splitting.

3.
J Transl Med ; 22(1): 795, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39198829

RESUMEN

BACKGROUND: Difficult-to-treat Rheumatoid arthritis (D2T RA) is primarily characterised by failure of at least two different mechanism of action biologic/targeted synthetic disease-modifying antirheumatic drug (DMARDs) with evidence of active/progressive disease. While a variety of drugs have been used in previous studies to treat D2T RA, there has been no systematic summary of these drugs. This study conducted a systematic review of randomized controlled trials aimed at analyzing the efficacy and safety of individual therapeutic agents for the treatment of D2T RA and recommending the optimal therapeutic dose. METHODS: The English databases were searched for studies on the treatment of D2T RA published between the date of the database's establishment and March, 2024. This study uses R 3.1.2 for data analysis, and the rjags package runs JAGS 3.4.0.20. The study fitted a stochastic effects Bayesian network meta-analysis for each outcome measure. RESULT: A total of 42 studies were included in this study. Compared with placebo, the improvement of Disease Activity Score of 28 Joints (DAS28) score is ranked from high to low as tocilizumab, baricitinib and opinercept. The improvement of American College of Rheumatology 50 response (ACR50) score in patients with drug use was ranked from good to poor as follows: olokizumab, tocilizumab, adalimumab, baricitinib, and upadacitinib, and 8 mg/4w tocilizumab demonstrated the best efficacy. Notably, rituximab is generally the safest drug. Janus kinase (JAK) inhibitors and T cell costimulation modulators are effective in D2T RA refractory to biologic DMARDs, while JAK inhibitors and interleukin-6 (IL-6) inhibitors show effectiveness in D2T RA refractory to csDMARDs. CONCLUSION: Tocilizumab and rituximab have better efficacy and safety in the treatment of D2T RA, and the 8 mg/4w dose of tocilizumab may be the first choice for achieving disease remission.


Asunto(s)
Antirreumáticos , Artritis Reumatoide , Humanos , Antirreumáticos/uso terapéutico , Antirreumáticos/efectos adversos , Artritis Reumatoide/tratamiento farmacológico , Metaanálisis en Red , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
4.
Chem Rec ; 24(1): e202300206, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37736673

RESUMEN

The development of sodium-ion battery (SIB) anodes is still hindered by their rapid capacity decay and poor rate capabilities. Although there have been some new materials that can be used to fabricate stable anodes, SIBs are still far from wide applications. Strategies like nanostructure construction and material modification have been used to prepare more robust SIB anodes. Among all the design strategies, the hollow structure design is a promising method in the development of advanced anode materials. In the past decade, research efforts have been devoted to modifying the synthetic route, the type of templates, and the interior structure of hollow structures with high capacity and stability. A brief introduction is made to the main material systems and classifications of hollow structural materials first. Then different morphologies of hollow structural materials for SIB anodes from the latest reports are discussed, including nanoboxes, nanospheres, yolk shells, nanotubes, and other more complex shapes. The most used templates for the synthesis of hollow structrual materials are covered and the perspectives are highlighted at the end. This review offers a comprehensive discussion of the synthesis of hollow structural materials for SIB anodes, which could be potentially of use to research areas involving hollow materials design for batteries.

5.
Small ; 19(46): e2304076, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37464549

RESUMEN

Plasma treatment and reduction are used to synthesize Pt nanoparticles (NPs) on nitrogen-doped carbon nanotubes (p-Pt/p-NCNT) with a low Pt content. In particular, the plasma treatment is used to treat the NCNT to give it with more surface defects, facilitating a better growth of the Pt NPs, while the plasma reduction produces the Pt NPs with a reduced fraction of the surface atoms at the high oxidation states, increasing the catalytic activities of the p-Pt@p-NCNT. Even at the low Pt content (7.8 wt.%), the p-Pt@p-NCNT shows superior catalytic activities and good stabilities for methanol oxidation reaction (MOR) and oxygen reduction reaction (ORR). The density functional theory (DFT) calculations indicate that the defects generated in the plasma treatment can help the growth of the Pt NPs on the NCNTs, leading to the stronger electronic coupling between Pt and NCNT and the increased stability of the catalyst. The plasma reduction can give the Pt NPs with optimized surface oxidation states, decreasing the energy barriers of the rate-determining steps for MOR and ORR. When used as the anode and cathode catalysts for the direct methanol fuel cells (DMFCs), the p-Pt@p-NCNT exhibits a higher maximum power density of 81.9 mW cm-2  at 80 °C and shows good durability.

6.
Small ; 18(30): e2201467, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35699694

RESUMEN

This work reports an amorphization and partial desulfurization method to improve the performance of sulfide-based materials for Na+ storage. Specifically, the polypyrrole derived carbon coated amorphous substoichiometric tin sulfide supported on aminated carbon nanotubes (PPY-C@SnSx /ACNTs) with amorphized and substoichiometric tin sulfide (SnSx ) is synthesized by simply thermal annealing the PPY-C@SnS2 /ACNTs. The PPY-C@SnSx /ACNTs shows stable reversible capacities of 410.2 mAh g-1 for Na+ storage at 0.1 A g-1 and excellent rate capacities of 270.2, 235.5, 217.4, and 210.0 mAh g-1 at 5.0, 10.0, 20.0, and 30.0 A g-1 , respectively. Nearly zero drops on the reversible capacities can be observed when it is sodiated/desodiated at 2.0, 5.0, and 10.0 A g-1 for up to 1000, 6500, 8000 cycles, respectively. Its outstanding rate capacities and degradation-free cycling stabilities mainly arise from the amorphized and substoichiometric structure of SnSx , which improve the reversible capacities and Na+ diffusivities of the PPY-C@SnSx /ACNTs. The density functional theory (DFT) calculations indicate that the partial desulfurization can improve the electric conductivity and promote the sodiation/desodiation of SnSx . It explains why the PPY-C@SnSx /ACNTs can exhibit high performance for Na+ storage well.

7.
Gynecol Obstet Invest ; 86(4): 361-369, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34464954

RESUMEN

OBJECTIVES: The objective of this study was to determine the relationship between the levels of stress biomarkers in cord blood and pre-eclampsia (PE) in a hospital-based population of pregnant patients and evaluate the effects on pregnancy outcomes. DESIGN: This was an observational, case-control study. Participants/Materials, Setting, Methods: This case-control study included 282 patients with severe PE and 534 women with normal pregnancy. The umbilical cord was collected at delivery and tested for malonaldehyde (MDA), reactive oxygen species (ROS), superoxide dismutase, and homocysteine (Hcy) analysis. We performed a univariate general linear regression model analysis to control potential confounders and determined the underlying influencing factors for high MDA and ROS. A receiver operating characteristic curve analysis was conducted to determine the cutoff values for identifying severe PE. Further, the severe PE group was divided into the low- or high-MDA and low- or high-ROS subgroups according to the cutoff values. Finally, we created logistic regression models to estimate the adjusted odds ratio for each perinatal outcome in the high-MDA and high-ROS subgroup. RESULTS: The levels of MDA and ROS levels were higher in women with severe PE than in normotensive pregnant patients. However, when adjusted for cord blood Hcy levels, the difference was insignificant. Additionally, both MDA (r = 0.359, p < 0.001) and ROS (r = 0.473, p < 0.001) were positively correlated with the cord blood Hcy level. The areas under the curve of MDA and ROS levels were 0.65 (95% confidence interval [CI]: 0.60-0.69) and 0.88 (95% CI: 0.86-0.90), respectively. Higher MDA and ROS levels were associated with increased risks of a low Apgar score, admission to the NICU, and assisted ventilation for the newborn. LIMITATIONS: The study design led to the exclusion of several participants. CONCLUSIONS: Increased levels of oxidative stress markers in the cord blood might be significantly associated with negative effects on newborns. High levels of Hcy in the cord blood might be associated with elevated MDA and ROS concentrations in women with severe PE.


Asunto(s)
Preeclampsia , Biomarcadores , Estudios de Casos y Controles , Femenino , Sangre Fetal , Humanos , Recién Nacido , Madres , Estrés Oxidativo , Embarazo
8.
J Clin Lab Anal ; 34(5): e23167, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31876071

RESUMEN

BACKGROUND: Lower serum homocysteine (Hcy) levels are found to correlate with a better chance of clinical pregnancy and better embryo grades in assisted reproductive technology (ART). However, there is little knowledge on the association between Hcy level and unexplained infertility until now. METHODS: A total of 388 infertile women undergoing IVF/ICSI treatments were recruited, including 129 women with unexplained causes (case group) and 259 women with known causes (control group), and the case group was further divided into subgroups A (≤8 µmol/L), B (>8 and <15 µmol/L), and C (≥15 µmol/L) based on the serum Hcy level. The associations between serum Hcy level and IVF/ICSI pregnancy outcomes were examined in infertile women with unknown causes. RESULTS: A significantly higher serum Hcy level was measured in the case group than in the control group (P = .008). Subgroup analysis revealed a significant difference in the total number of oocytes retrieved among subgroups A, B, and C (P = .031), and no significant difference was seen among these three groups in terms of age, BMI, E2 level on the hCG day, number of M-II oocytes, number of fertilized oocytes, or total number of high-quality embryos (P > .05). Spearman correlation analysis revealed a negative correlation between serum Hcy level and total number of oocytes retrieved (r = -.406, P = .019). Univariate and multivariate linear regression analyses revealed that serum Hcy level had no correlations with any IVF/ICSI outcomes. CONCLUSION: Serum Hcy level has no associations with IVF/ICSI pregnancy outcomes.


Asunto(s)
Homocisteína/sangre , Infertilidad Femenina/terapia , Adulto , Estudios de Casos y Controles , Femenino , Fertilización In Vitro , Hospitales , Humanos , Infertilidad Femenina/sangre , Infertilidad Femenina/etiología , Masculino , Oocitos , Embarazo , Resultado del Embarazo , Estudios Retrospectivos , Inyecciones de Esperma Intracitoplasmáticas
9.
J Cell Physiol ; 234(8): 13820-13831, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30644094

RESUMEN

Recently, graphene nanomaterials have attracted tremendous attention and have been utilized in various fields because of their excellent mechanical, thermal, chemical, optical properties, and good biocompatibility, especially in biomedical aspects. However, there is a concern that the unique characteristics of nanomaterials may have undesirable effects. Therefore, in this study, we sought to systematically investigate the effects of graphene quantum dots (GQDs) on the maturation of mouse oocytes and development of the offspring via in vitro and in vivo studies. In vitro, we found that the first polar body extrusion rate in the high dosage exposure groups (1.0-1.5 mg/ml) 2 decreased significantly and the failure of spindle migration and actin cap formation after GQDs exposure was observed. The underlying mechanisms might be associated with reactive oxygen species accumulation and DNA damage. Moreover, transmission electron microscope studies showed that GQDs may have been internalized into oocytes, tending to accumulate in the nucleus and severely affecting mitochondrial morphology, which included swollen and vacuolated mitochondria accompanied by cristae alteration with a lower amount of dense mitochondrial matrix. In vivo, when pregnant mice were exposed to GQDs at 8.5 days of gestation (GD, 8.5), we found that high dosage of GQD exposure (30 mg/kg) significantly affected mean fetal length; however, all the second generation of female mice grew up normal, attained sexual maturity, and gave birth to a healthy offspring after mating with a healthy male mouse. The results presented in this study are important for the future investigation of GQDs for the biomedical applications.


Asunto(s)
Desarrollo Embrionario/efectos de los fármacos , Grafito/farmacología , Oocitos/citología , Puntos Cuánticos/química , Actinas/metabolismo , Animales , Roturas del ADN de Doble Cadena/efectos de los fármacos , Femenino , Feto/efectos de los fármacos , Feto/embriología , Masculino , Metafase/efectos de los fármacos , Ratones , Mitocondrias/efectos de los fármacos , Mitocondrias/ultraestructura , Oocitos/efectos de los fármacos , Oocitos/metabolismo , Oocitos/ultraestructura , Puntos Cuánticos/ultraestructura , Especies Reactivas de Oxígeno/metabolismo , Huso Acromático/efectos de los fármacos , Huso Acromático/metabolismo , Difracción de Rayos X
10.
Anal Chem ; 91(9): 5824-5833, 2019 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-30917656

RESUMEN

In this work, we report a new biosensing platform for hepatitis B virus (HBV) DNA genosensing using cobalt oxide (Co3O4) nanostructures. The tunable morphologies of Co3O4 nanostructures such as porous nanocubes (PNCs), nanooctahedra (NOHs), and nanosticks (NSKs) are synthesized, and characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) patterns, nitrogen adsorption/desorption isotherms (BET), and electrochemical impedance spectral (EIS) methods. The HBV probe DNA (ssDNA) is immobilized on the Co3O4 nanostructures through coordinate bond formation between nucleic acid of ssDNA and Co metal, which results in highly stable nanostructured biosensing platform. To the best of our knowledge, first time the target cDNA of HBV is detected using ssDNA/Co3O4PNCs/GCE electrode by EIS method with a limit of detection (LOD) of 0.38 pM (signal-to-noise ratio (S/N) = 3). Moreover, the ssDNA/Co3O4PNCs/GCE has shown excellent specificity to HBV target cDNA, compared with noncomplementary DNA, and 1- and 3-mismatch DNAs. Finally, we explore ssDNA/Co3O4PNCs/GCE as potential electrode to test HBV DNA in blood serum and urine samples for practical applications.


Asunto(s)
Técnicas Biosensibles/métodos , Cobalto/química , ADN Viral/sangre , ADN Viral/orina , Virus de la Hepatitis B/genética , Hepatitis B/diagnóstico , Nanoestructuras/química , Óxidos/química , ADN Viral/genética , Técnicas Electroquímicas/métodos , Hepatitis B/sangre , Hepatitis B/orina , Virus de la Hepatitis B/aislamiento & purificación , Humanos
11.
Angew Chem Int Ed Engl ; 58(42): 15010-15015, 2019 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-31478303

RESUMEN

A two-dimensional (2D) carbon nanofilm with uniform artificial nanopores is an ideal material to ultimately suppress the fuel permeation in the proton exchange membrane fuel cells. Graphdiyne has great mechanical strength, high dimensional stability, and controllable nanopores, and has good prospects to play this crucial role. It is found that graphdiyne nanofilm with amino groups and natural nanopores can be easily prepared with high integrity. The aminated graphdiyne has good compatibility with the Nafion matrix owing to the acid-base interaction between them. The excellent comprehensive properties of graphdiyne in selectivity, dimensional stability, and integrity effectively improve the power performance and stability of fuel cells at wide temperature. Our results can be developed into a universal method that can easily realize the selective separation of ions and small molecules, and open a new way for the emerging applications in green energy.

12.
Cogn Process ; 17(4): 357-375, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27342411

RESUMEN

Researchers have been at odds on whether affective or semantic priming is faster or stronger. The present study selects a series of facial expression photos and words, which have definite emotional meaning or gender meaning, to set up experiment including both affective and semantic priming. The intensity of emotion and gender information in the prime as well as the strength of emotional or semantic (in gender) relationship between the prime and the target is matched. Three groups of participants are employed separately in our experiment varied with stimulus onset asynchrony (SOA) as 50, 250 or 500 ms. The results show that the difference between two types of priming effect is revealed when the SOA is at 50 ms, in which the affective priming effect is presented when the prime has negative emotion. It indicates that SOA can affect the comparison between the affective and semantic priming, and the former takes the priority in the automatic processing level.


Asunto(s)
Afecto/fisiología , Asociación , Tiempo de Reacción/fisiología , Semántica , Adolescente , Adulto , Análisis de Varianza , Señales (Psicología) , Expresión Facial , Femenino , Humanos , Estimulación Luminosa , Factores de Tiempo , Vocabulario , Adulto Joven
13.
J Psycholinguist Res ; 45(4): 769-78, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25980970

RESUMEN

To explore how the sentence contexts affect self-positivity bias, we presented the participants with negation and affirmation sentences. Each sentence was ended with an adjective word describing human being's personality. The participants were asked to judge whether the sentences correctly described their own personalities. In affirmation sentences, the behavioral data showed that self-positivity bias occurred when participants considered the sentences to be in accordance with their personality; the ERP data showed that P200 amplitude was consistent with this behavioral result. In negation sentences, behavioral data showed self-positivity bias, regardless of whether the sentences were in accordance with participants' personality or not. However, the self-positivity bias was not observed in the ERP results from negation sentence. In summary, sentence type modulated the effect of self-positivity bias. The reason could be that processing affirmation and negation sentences requires different amount of cognitive resources.


Asunto(s)
Potenciales Evocados/fisiología , Personalidad/fisiología , Psicolingüística , Lectura , Autoevaluación (Psicología) , Adulto , Femenino , Humanos , Masculino , Adulto Joven
14.
Small Methods ; 8(3): e2301342, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37997209

RESUMEN

The carbon nanotubes (CNTs) supported amorphous Sb doped substoichiometric tin dulfide (Sb─SnSx ) with a carbon coating (the C/Sb─SnSx @CNTs-500) is reported to be an efficient anode material for K+ storage. The formation of the C/Sb─SnSx @CNTs-500 is simply achieved through the thermally induced desulfurization of tin sulfide via a controlled annealing of the C/Sb─SnS2 @CNTs at 500 °C. When used for the K+ storage, it can deliver stable reversible capacities of 406.5, 305.7, and 238.4 mAh g-1 at 0.1, 1.0, and 2.0 A g-1 , respectively, and shows no capacity drops when potassiated/depotassiated at 1.0 and 2.0 A g-1 for >3000 and 2400 cycles, respectively. Even at 10, 20, and 30 A g-1 , it can still deliver stable reversible capacities of 138.5, 85.1, and 73.8 mAh g-1 , respectively. The unique structure, which combines the advantageous features of carbon integration/coating, metal doping, and desulfurization-induced amorphous structure, is the main origin of the high performance of the C/Sb─SnSx @CNTs-500. Specifically, the carbon integration/coating can increase the electric conductivity and stability of the C/Sb─SnSx @CNTs-500. The density function theory calculation indicates that the Sb doping and the desulfurization can facilitate the potassiation and increase the electric conductivity of Sb─SnSx . Additionally, the desulfurization can increase the K+ diffusivity in Sb─SnSx .

15.
ChemSusChem ; : e202400254, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38743510

RESUMEN

Environmental pollution caused by persistent organic pollutants has imposed big threats to the health of human and ecological systems. The development of efficient methods to effectively degrade and remove these persistent organic pollutants is therefore of paramount importance. Photocatalytic persulfate-based advanced oxidation technologies (PS-AOTs), which depend on the highly reactive SO4 - radicals generated by the activation of PS to degrade persistent organic pollutants, have shown great promise. This work discusses the application and modification strategies of common photocatalysts in photocatalytic PS-AOTs, and compares the degradation performance of different catalysts for pollutants. Furthermore, essential elements impacting photocatalytic PS-AOTs are discussed, including the water matrix, reaction process mechanism, pollutant degradation pathway, singlet oxygen generation, and potential PS hazards. Finally, the existing issues and future challenges of photocatalytic PS-AOTs are summarized and prospected to encourage their practical application. In particular, by providing new insights into the PS-AOTs, this review sheds light on the opportunities and challenges for the development of photocatalysts with advanced features for the PS-AOTs, which will be of great interests to promote better fundamental understanding of the PS-AOTs and their practical applications.

16.
J Colloid Interface Sci ; 668: 525-539, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38691962

RESUMEN

Economical oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) bifunctional catalysts with high activity aimed at replacing precious metal catalysts for rechargeable zinc-air batteries (ZABs) must be developed. In this study, a multiple hierarchical-structural material is developed using a facile dielectric barrier discharge (DBD) plasma surface treatment, solvothermal reaction, and high-temperature carbonization strategy. This strategy allows for the construction of nanosheets using nitrogen-doped carbon (NC) material-encapsulated ternary CoNiFe alloy nanoparticles (NPs) on a network of NC nanotubes (NCNTs), denoted as CoNiFe-NC@p-NCNTs. Precisely, the presence of abundant CoNiFe alloy NPs and the formation of M-N-C active sites created by transition metals (cobalt, nickel, and iron) coupled with NC can provide superior OER/ORR bifunctional properties. Moreover, the prepared NC layers with a multilevel pore structure contribute to a larger specific surface area, exposing numerous active sites and enhancing the uniformity of electron and mass movement. The CoNiFe0.08-NC@p-NCNTs show remarkable dual functionality for electrochemical oxygen reactions (ORR half-wave potential of 0.811 V, limiting current density of 5.73 mA cm-2 measured with a rotating disk electrode at a rotation speed of 1600 rpm, and OER overpotential of 351 mV at 10 mA cm-2), which demonstrates similar ORR performance to 20 wt% Pt/C and better OER performance than the commercial RuO2. A liquid ZAB prepared using the proposed material has excellent bifunctionality with an open-circuit voltage of 1.450 V and long-term cycling stability of 230 h@10 mA cm-2.

17.
Adv Mater ; 36(13): e2306934, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38135663

RESUMEN

The development of cost-effective catalysts for oxygen evolution reaction (OER) in acidic media is of paramount importance. This work reports that Sr-doped solid solution structural ultrafine IrMnO2 nanoparticles (NPs) (≈1.56 nm) on the carbon nanotubes (Sr-IrMnO2/CNTs) are efficient catalysts for the acidic OER. Even with the Ir use dosage 3.5 times lower than that of the commercial IrO2, the Sr-IrMnO2/CNTs only need an overpotential of 236.0 mV to drive 10.0 mA cm-2 and show outstanding stability for >400.0 h. Its Ir mass activity is 39.6 times higher than that of the IrO2 at 1.53 V. The solid solution and Sr-doping structure of Sr-IrMnO2 are the main origin of the high catalytic activity and excellent stability of the Sr-IrMnO2/CNTs. The density function theory calculations indicate that the solid solution structure can promote strong electronic coupling between Ir and Mn, lowering the energy barrier of the OER rate-determining step. The Sr-doping can enhance the stability of Ir against the chemical corrosion and demetallation. Water electrolyzers and proton exchange membrane water electrolyzers assembled with the Sr-IrMnO2/CNTs show superb performance and excellent durability in the acid media.

18.
Small Methods ; : e2400565, 2024 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-38923872

RESUMEN

This work utilizes defect engineering, heterostructure, pyridine N-doping, and carbon supporting to enhance cobalt-nickel selenide microspheres' performance in the oxygen electrode reaction. Specifically, microspheres mainly composed of CoNiSe2 and Co9Se8 heterojunction rich in selenium vacancies (VSe·) wrapped with nitrogen-doped carbon nanotubes (p-CoNiSe/NCNT@CC) are prepared by Ar/NH3 radio frequency plasma etching technique. The synthesized p-CoNiSe/NCNT@CC shows high oxygen reduction reaction (ORR) performance (half-wave potential (E1/2) = 0.878 V and limiting current density (JL) = 21.88 mA cm-2). The JL exceeds the 20 wt% Pt/C (19.34 mA cm-2) and the E1/2 is close to the 20 wt% Pt/C (0.881 V). It also possesses excellent oxygen evolution reaction (OER) performance (overpotential of 324 mV@10 mA cm-2), which even exceeds that of the commercial RuO2 (427 mV@10 mA cm-2). The density functional theory calculation indicates that the enhancement of ORR performance is attributed to the synergistic effect of plasma-induced VSe· and the CoNiSe2-Co9Se8 heterojunction. The p-CoNiSe/NCNT@CC electrode assembled Zinc-air batteries (ZABs) show a peak power density of 138.29 mW cm-2, outperforming the 20 wt% Pt/C+RuO2 (73.9 mW cm-2) and other recently reported catalysts. Furthermore, all-solid-state ZAB delivers a high peak power density of 64.83 mW cm-2 and ultra-robust cycling stability even under bending.

19.
Nanomicro Lett ; 16(1): 250, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39023812

RESUMEN

This work reports the use of defect engineering and carbon supporting to achieve metal-doped phosphides with high activities and stabilities for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) in alkaline media. Specifically, the nitrogen-doped carbon nanofiber-supported Ni-doped CoP3 with rich P defects (Pv·) on the carbon cloth (p-NiCoP/NCFs@CC) is synthesized through a plasma-assisted phosphorization method. The p-NiCoP/NCFs@CC is an efficient and stable catalyst for the HER and the OER. It only needs overpotentials of 107 and 306 mV to drive 100 mA cm-2 for the HER and the OER, respectively. Its catalytic activities are higher than those of other catalysts reported recently. The high activities of the p-NiCoP/NCFs@CC mainly arise from its peculiar structural features. The density functional theory calculation indicates that the Pv· richness, the Ni doping, and the carbon supporting can optimize the adsorption of the H atoms at the catalyst surface and promote the strong electronic couplings between the carbon nanofiber-supported p-NiCoP with the surface oxide layer formed during the OER process. This gives the p-NiCoP/NCFs@CC with the high activities for the HER and the OER. When used in alkaline water electrolyzers, the p-NiCoP/NCFs@CC shows the superior activity and excellent stability for overall water splitting.

20.
Biol Psychol ; 187: 108774, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38471619

RESUMEN

There has been disagreement regarding the relationship among the three components (subjective experience, external performance, and physiological response) of emotional responses. To investigate this issue further, this study compared the effects of active and passive suppression of facial expressions on subjective experiences and event-related potentials (ERPs) through two experiments. The two methods of expression suppression produced opposite patterns of ERPs for negative emotional stimuli: compared with the free-viewing condition, active suppression of expression decreased, while passive suppression increased the amplitude of the late positive potential (LPP) when viewing negative emotional stimuli. Further, while active suppression had no effect on participants' emotional experience, passive suppression enhanced their emotional experience. Among the three components of emotional responses, facial expressions are more closely related to the physiological response of the brain than to subjective experience, and whether the suppression was initiated by participants determines the decrease or increase in physiological response of the brain (i.e. LPP). The findings revealed the important role of individual subjective initiative in modulating the relationship among the components of emotional response, which provides new insights into effectively emotional regulation.


Asunto(s)
Regulación Emocional , Expresión Facial , Humanos , Potenciales Evocados/fisiología , Emociones/fisiología , Encéfalo/fisiología , Electroencefalografía
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