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1.
J Colloid Interface Sci ; 669: 402-418, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38723530

RESUMO

In this study, copper oxide (CuO) was prepared by the microwave-assisted hydrothermal technique subsequently, CuO was grown in situ onto different rare metal compounds to prepare Z-scheme heterojunctions to improve the degradation efficiency of tetracycline (TC) in water environments. Various characterization proved the successful synthesis of all composite materials, and the formation of tight heterojunction interfaces, among which, the core-shell structure ZnIn2S4@CuO exhibited excellent photocatalytic degradation capability. Research results indicated that the degradation efficiency of ZnIn2S4@CuO for TC (50 mg/L) in the water environment reached 95.8 %, and the degradation rate is 2.41 times and 12.93 times that of CuO and ZnIn2S4 alone, respectively, the reason is because of the introduction of ZnIn2S4, Z-scheme heterojunction structures and internal electric field (IEF) is constructed and formed to extend the visible light response range of photocatalysts to improve electron-hole separation efficiency, and enhance charge transfer. In addition, ZnIn2S4@CuO-2 exhibited good stability and reproducibility, with no significant loss of activity after five cycles. Finally, the precise locations of free radical attack on TC were investigated by the combined use of high-resolution mass spectrometry (HR-MC) and frontier electron densities (FEDs), and a reasonable degradation pathway was provided. The results of this research provide a new and viable approach to overcome the limitations of conventional photocatalytic materials in terms of limited visible light absorption range and fast carrier recombination rates, which offers promising prospects for a wide range of applications in the field of wastewater purification.

2.
J Family Med Prim Care ; 13(3): 1020-1023, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38736809

RESUMO

Background: Anterior cervical discectomy and fusion is the most commonly used surgical approach for treating cervical spine conditions, but it can often lead to postoperative swallowing difficulties. To retrospectively assess the effects of topical triamcinolone acetonide in the anterior cervical surgery on swallowing function. Methods: In this study, a retrospective design was used to select patients aged 18 years and older who were diagnosed with cervical spondylosis and required anterior cervical discectomy and fusion. Among them, the patients in the experimental group used triamcinolone acetonide topically in front of the plate during surgery, and the control group was the patients who did not use triamcinolone acetonide. The sex, age, operation time, operation segment, and preoperative soft tissue area were compared between the two groups. Results: There were no significant differences in gender, age, operation time, and segment between the two groups. For the preoperative soft tissue area, triamcinolone acetonide was significantly lower than in the control group (P < 0.05). Conclusion: The retrospective results of this study support that topical triamcinolone acetonide as a treatment in anterior cervical surgery can significantly reduce soft tissue swelling, and no effect was found on the operation time, postoperative blood loss, and segment. These findings provide an important basis for clinical care teams to make treatment decisions and confirm the effectiveness of triamcinolone acetonide in improving swallowing function. However, there was a possibility of information collection and selection bias due to the limitations of retrospective studies. To confirm and further advance the use of this treatment, more rigorous prospective randomized controlled trials are recommended to validate these preliminary results.

3.
Aging Dis ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38739936

RESUMO

Aging-related hypogonadism involves complex mechanisms in humans, predominantly relating to the decline of multiple hormones and senile gonads. Late-onset hypogonadism (LOH) and erectile dysfunction (ED) are the main manifestations in men, while premature ovarian insufficiency (POI) and menopause are the main forms in women. Anti-aging measures include lifestyle modification and resistance training, hormonal supplementation, stem cell therapy, metformin, and rapamycin. In this expert consensus, the mechanisms, efficacy, and side effects of stem cell therapy on aging gonadal function are reviewed. Furthermore, various methods of stem cell therapy, administered intravenously, intracavernously, and intra-ovarially, are exemplified in detail. More clinical trials on aging-related gonadal dysfunction are required to solidify the foundation of this topic.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38648136

RESUMO

The development of high-temperature nondestructive testing (NDT) requires ultrasonic transducers with good temperature resistance and high sensitivity for improved detection efficiency. Piezoelectric composite can improve the performance of transducers because of its high electromechanical coupling coefficient and adjustable acoustic impedance. In this study, 1-3-2 composites and 1-3-2 high-temperature composite ultrasonic transducers (HTCUTs) based on 0.36BiScO3-0.64PbTiO3 (BSPT), which are preferred piezoelectric materials at 200°C-300°C, and high-temperature epoxy with a center frequency of 6 MHz were designed and fabricated. From 25°C to 250°C, 1-3-2 composites show a higher electromechanical coupling coefficient kt especially at high temperatures (~0.53 at 25°C, and ~0.64 at 250°C) than monolithic BSPT (~0.5). The signal of the pulse-echo response of 1-3-2 HTCUTs is distinguishable up to 250 °C and remains stable (Vpp~500 mV) below 150°C, exhibiting higher sensitivity (improved by 7 dB) than that of monolithic BSPT high-temperature ultrasonic transducers (HTUTs). Bandwidth has been greatly enhanced especially at high temperatures (~103250°C) compared with that of monolithic BSPT HTUTs(~30250°C). To verify the excellent performance, B-mode scanning imaging measurement of a stepped steel block and defect location detection of a steel block were performed, showing the potential for high-temperature NDT applications.

5.
Nano Lett ; 24(15): 4408-4414, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38567928

RESUMO

Tuning the interfacial Schottky barrier with van der Waals (vdW) contacts is an important solution for two-dimensional (2D) electronics. Here we report that the interlayer dipoles of 2D vdW superlattices (vdWSLs) can be used to engineer vdW contacts to 2D semiconductors. A bipolar WSe2 with Ba6Ta11S28 (BTS) vdW contact was employed to exhibit this strategy. Strong interlayer dipoles can be formed due to charge transfer between the Ba3TaS5 and TaS2 layers. Mechanical exfoliation breaks the superlattice and produces two distinguished surfaces with TaS2 and Ba3TaS5 terminations. The surfaces thus have opposite surface dipoles and consequently different work functions. Therefore, all the devices fall into two categories in accordance with the rectifying direction, which were verified by electrical measurements and scanning photocurrent microscopy. The growing vdWSL family along with the addition surface dipoles enables prospective vdW contact designs and have practical application in nanoelectronics and nano optoelectronics.

6.
Nano Lett ; 24(18): 5467-5473, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38647318

RESUMO

The discovery of room-temperature ferromagnetism in van der Waals (vdW) materials opens new avenues for exploring low-dimensional magnetism and its applications in spintronics. Recently, the observation of the room-temperature topological Hall effect in the vdW ferromagnet Fe3GaTe2 suggests the possible existence of room-temperature skyrmions, yet skyrmions have not been directly observed. In this study, real-space imaging was employed to investigate the domain evolution of the labyrinth and skyrmion structure. First, Néel-type skyrmions can be created at room temperature. In addition, the influence of flake thickness and external magnetic field (during field cooling) on both labyrinth domains and the skyrmion lattice is unveiled. Due to the competition between magnetic anisotropy and dipole interactions, the specimen thickness significantly influences the density of skyrmions. These findings demonstrate that Fe3GaTe2 can host room-temperature skyrmions of various sizes, opening up avenues for further study of magnetic topological textures at room temperature.

7.
Respir Med Case Rep ; 48: 102002, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38510662

RESUMO

This study presents a rare case of plastic bronchitis (PB) in a 57-year-old adult post-lung lobectomy, a condition predominantly found in post-Fontan children. The patient exhibited progressive dyspnea and complete atelectasis on the surgical side, revealing a gray rubbery bronchial cast obstructing the right main bronchus. Treatment involved repeated bronchoscopies, glucocorticoids, acetylcysteine, physiotherapy, and a low-fat diet, leading to gradual improvement. No similar cases have been reported, highlighting PB's diagnostic challenge. This underscores the need to consider rare conditions like PB in post-lobectomy complications. Timely examinations and bronchoscopies are essential for accurate diagnosis, ensuring prompt treatment and improving patient outcomes.

8.
J Colloid Interface Sci ; 662: 263-275, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38354554

RESUMO

Defect-engineered metal-organic frameworks (DEMOFs) are emerging advanced materials. The construction of DEMOFs is of great significance; however, DEMOF-based catalysis remains unexplored. (E)-vinylboronates, an important building block for asymmetric synthesis, can be synthesized via the hydroboration of alkynes. However, the lack of high-performance catalysts considerably hinders their synthesis. Herein, a series of DEHKUST-1 (HKUST = Hong Kong University of Science and Technology) (Da-f) catalysts with missing occupation of linkers at Cu nodes were designed by partially replacing benzene-1,3,5-tricarboxylate (H3BTC) with defective connectors of pyridine-3,5-dicarboxylate (PYDC) to efficiently promote the hydroboration of alkynes. Results showed that the Dd containing 0.8 doping ratio of PYDC exhibited remarkable catalytic activity than the defect-free HKUST-1. This originated from the improved accessibility for reactants towards the Lewis acid active Cu sites of DEHKUST-1 due to the presence of plenty of rooms next to the Cu sites and enhanced coordination ability in such 'defective' HKUST-1. Dd had high selectivity (>99 %) and yield (>96 %) for (E)-vinylboronates and extensive functional group compatibility for terminal alkynes. Density functional theory (DFT) calculations were performed to elucidate the mechanism of hydroboration. Compared with that of defect-free HKUST-1, the low energy barrier of DEHKUST-1 can be attributed to the lower coordination number of Cu sites and enhanced accessibility of Cu active sites towards reagents.

9.
Environ Sci Technol ; 58(2): 1164-1176, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38164759

RESUMO

Terrestrial dissolved organic matter (DOM) is critical to global carbon and nutrient cycling, climate change, and human health. However, how the spatial and compositional differences of soil DOM affect its dynamics and fate in water during the carbon cycle is largely unclear. Herein, the biodegradation of DOM from 14 spatially distributed grassland soils in China with diverse organic composition was investigated by 165 days of incubation experiments. The results showed that although the high humified fraction (high-HS) regions were featured by high humic-like fractions of 4-25 kDa molecular weight, especially the abundant condensed aromatics and tannins, they unexpectedly displayed greater DOM degradation during 45-165 days. In contrast, the unique proteinaceous and 25-100 kDa fractions enriched in the low humified fraction (low-HS) regions were drastically depleted and improved the decay of bulk DOM but only during 0-45 days. Together, DOM from the high-HS regions would cause lower CO2 outgassing to the atmosphere but higher organic loads for drinking water production in the short term than that from the low-HS regions. However, this would be reversed for the two regions during the long-term transformation processes. These findings highlight the importance of spatial and temporal variability of DOM biogeochemistry to mitigate the negative impacts of grassland soil DOM on climate, waters, and humans.


Assuntos
Matéria Orgânica Dissolvida , Solo , Humanos , Pradaria , Carbono , Água , China
10.
BMC Urol ; 24(1): 1, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166868

RESUMO

BACKGROUND: There are few studies on cryptorchidism in adults, and its treatment is still controversial. METHODS: To summarize the surgical strategy and clinical efficacy of laparoscopic orchidopexy for the treatment of cryptorchidism in adults, 37 adult cryptorchidism patients were retrospectively analyzed between September 2017 and February 2022. All 37 patients underwent laparoscopic orchidopexy, of whom 33 underwent inguinal hernia repair without tension. The intraoperative procedures and surgical techniques were recorded in detail. Preoperative examination and regular postoperative review of color Doppler ultrasound, and reproductive hormone, alpha-fetoprotein, human chorionic gonadotropin, and lactate dehydrogenase levels were performed. RESULTS: All testes descended successfully into the scrotum, including 25 through the inguinal route and 12 through Hesselbach's triangle route. No intraoperative or postoperative complications were observed. The follow-up time was 38.6 (± 19.4) months, and no evidence of testicular malignancy was found during the follow-up period. After analyzing the reproductive hormone levels at 1 year postoperatively in 28 patients with more than 1 year of follow-up, it was found that the patients had a significant increase in testosterone levels and a decrease in follicle-stimulating hormone levels after surgery. None of the patients showed any significant improvement in semen quality after surgery. CONCLUSION: Our study suggests that laparoscopic orchidopexy is a safe and feasible surgical procedure for the treatment of cryptorchidism in adults, especially high cryptorchidism, which is difficult to treat. After comprehensive consideration, preserving the testis should be preferred for treating cryptorchidism in adults to maximize the protection of the patient's reproductive hormone secretion function.


Assuntos
Criptorquidismo , Laparoscopia , Masculino , Humanos , Lactente , Criptorquidismo/cirurgia , Criptorquidismo/diagnóstico , Orquidopexia/métodos , Estudos Retrospectivos , Análise do Sêmen , Laparoscopia/métodos , Testículo , Resultado do Tratamento , Hormônios
11.
J Pain Res ; 16: 4191-4207, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38090024

RESUMO

Objective: In this study, we aimed to explore the demographic and clinical factors that could determine short- and long-term complete pain relief (CPR) in adult patients with primary trigeminal neuralgia (PTN) after microvascular decompression (MVD) to guide clinical practice. Methods: This single-center retrospective study included adult patients with PTN who underwent MVD as their initial neurosurgical procedure in the Department of Neurosurgery at the Second Affiliated Hospital of Harbin Medical University from January 2017 to December 2019 and completed a 3-year post-surgery follow-up. Demographic and clinical information was obtained from medical records. Pain relief of adult patients with PTN at various time points after sufficient decompression of trigeminal nerve (TN) during MVD was determined and classified by the patient's subjective response and medications use. Pain relief of local patients was evaluated by outpatient follow-up at various time points, whereas that of local cases who could not return to outpatient or non-local cases was assessed through telephone or WeChat. Results: In univariate analysis, compression degree of TN and type of conflicting vessels constantly showed significant differences between the two groups at 3 months, 6 months, 1 year, 2 years, and 3 years after MVD. Compression degree of TN and type of conflicting vessels at various time points after MVD were always the related factors to CPR in logistic regression analysis, with the former having the greatest impact. The areas under the receiver operating characteristic (ROC) curve of CPR at various time points after MVD were 0.937, 0.874, 0.879, 0.864, and 0.869, respectively. Conclusion: In summary, compression degree of TN and type of conflicting vessels can determine short- and long-term CPR in adult patients with PTN after MVD.

12.
J Mater Chem B ; 11(40): 9721-9731, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37791430

RESUMO

Gene therapy is a promising strategy for HCC treatment, but it commonly faces the problem of low specificity in gene transfection. In this study, we designed and synthesized a series of peptide-based gene delivery vectors (H-01 to H-18) containing varied HCC cell-targeting fragments for specifically binding different receptors highly expressed on HCC cell membranes. The physicochemical properties of peptide vectors or peptide/DNA complexes were characterized, and the gene delivery abilities of peptide vectors were evaluated in HepG2 cell lines. The results showed that peptide vectors H-02 and H-09, which contained targeted fragments for ACE2 and c-Met receptors, respectively, could specifically transfect HCC cells in a highly -efficient manner in vitro. Furthermore, the liver-targeting function in vivo of Cy5.5 labeled H-02 (H-17) and H-09 (H-18) was investigated by fluorescence imaging.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Peptídeos/química , Terapia Genética
13.
Opt Lett ; 48(15): 3909-3912, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37527080

RESUMO

Reversed nonlinear dynamics is predicted to be capable of enhancing the quantum sensing in unprecedented ways. Here, we report the experimental demonstration of a loss-tolerant (external loss) and quantum-enhanced interferometer. Two cascaded optical parametric amplifiers are used to judiciously construct an interferometry with two orthogonal squeezing operation. As a consequence, a weak displacement introduced by a test cavity can be amplified for measurement, and the measured signal-to-noise ratio is better than that of both conventional photon shot-noise limited and squeezed-light assisted interferometers. We further confirm its superior loss-tolerant performance by varying the external losses and comparing with both conventional photon shot-noise limited and squeezed-light assisted configurations, illustrating the potential application in gravitational wave detection.

14.
J Cardiovasc Electrophysiol ; 34(9): 1843-1849, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37632286

RESUMO

INTRODUCTION: This study aimed to identify the characteristics of unipolar and bipolar electrogram (UniEGM and BiEGM) in guiding successful ablation of premature ventricular contractions (PVCs) originating from the free wall of the ventricular aspect of the tricuspid annulus (TA). We hypothesized that the negative concordance pattern (NCP) on the onset of UniEGM and BiEGM, together with the least value of the difference between the earliest BiEGM and UniEGM dV/dTmax, might improve the accuracy of conventional mapping. METHODS AND RESULTS: Thirty consecutive patients who underwent successful catheter ablation from February 2018 to July 2021 were retrospectively analyzed. The BiEGM and UniEGM for successful ablation sites were compared with those for non-successful ablation sites. Among the 30 patients, 30 successful and 26 nonsuccessful ablation sites were compared. The earliest activation time of the BiEGM (BiEGMoneset-QRS) was 25 ± 6 ms for the successful ablation sites and 21 ± 6 ms for the nonsuccessful ablation sites (p = .47). The value of the difference in the earliest BiEGM and UniEGM dV/dTmax differed between successful and nonsuccessful ablation sites (6.4 ± 3.6 ms vs. 10.4 ± 6.8 ms). NCP was observed at 90.0% and 42.3% of the successful and nonsuccessful ablation sites, respectively. Alignment of NCP and BiEGMonset-UniEGM ≤6 ms was applied as the mapping criterion for successful PVC suppression (73.1% sensitivity and 87.7% specificity). The area under the receiver-operating characteristic curve for this cutoff was 0.85. CONCLUSION: Mapping based on an NCP at the onset of the BiEGM and UniEGM and the least difference value of the earliest BiEGM and UniEGM dV/dTmax had an excellent predictive value for successful ablation. These strategies may reduce the number of radiofrequency catheter ablation (RFCA) applications for free-wall tricuspid annular PVCs.


Assuntos
Ablação por Cateter , Complexos Ventriculares Prematuros , Humanos , Complexos Ventriculares Prematuros/diagnóstico , Complexos Ventriculares Prematuros/cirurgia , Estudos Retrospectivos , Ventrículos do Coração , Ablação por Cateter/efeitos adversos , Curva ROC
15.
Zhongguo Fei Ai Za Zhi ; 26(6): 407-415, 2023 Jun 20.
Artigo em Chinês | MEDLINE | ID: mdl-37488078

RESUMO

Lung cancer is the malignant tumor with the highest morbidity and mortality in China. Non-small cell lung cancer (NSCLC) is the main pathological subtype of lung cancer. On April 13, 2023, the National Comprehensive Cancer Network (NCCN) released the third edition of the 2023 NCCN Oncology Clinical Practice Guidelines: Non-small Cell Lung Cancer, which reflects the latest advances in international lung cancer research. This article will interpret the main updated contents of the new edition of the guidelines, and compare it with the third edition of the NCCN guidelines in 2022, so as to provide references about the diagnosis and treatment of NSCLC for clinical medical personnel in China.
.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , China , Tórax
16.
IEEE Trans Image Process ; 32: 4088-4102, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37432829

RESUMO

Millimeter-wave (MMW) imaging techniques have been widely used in the public security industries for their under-controlled privacy concerns and no health hazards. However, since MMW images are low resolution and most objects are small, reflection-weak, diverse, suspicious object detection in the MMW images is a very challenging task. This paper develops a robust suspicious object detector for the MMW images based on the Siamese network integrated with the pose estimation and image segmentation, which estimates the coordinates of human joints and segments the complete human images into symmetrical body part images. Unlike most existing detectors, which detect and recognize suspicious objects in MMW images and require a complete training set with correct annotations, our proposed model aims to learn the similarity between two symmetrical human body part images segmented from the complete MMW images. Furthermore, to decrease the misdetection caused by the restricted field of view, we further fuse the multi-view MMW images observed from the same person by designing a decision-level fusion strategy and feature-level fusion strategy based on the attention mechanism. Experimental results on the measured MMW images show that our proposed models have favorable detection accuracy and speed in practical application and thus prove their effectiveness.

18.
J Lipid Res ; 64(7): 100398, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37276941

RESUMO

Lipoprotein(a) (Lp(a)) is a largely genetically determined biomarker for cardiovascular disease (CVD), while its potential interplay with family history (FHx) of CVD, a measure of both genetic and environmental exposures, remains unclear. We examined the associations of Lp(a) in terms of circulating concentration or polygenetic risk score (PRS), and FHx of CVD with risk of incident heart failure (HF). Included were 299,158 adults from the UK Biobank without known HF and CVD at baseline. Hazards ratios (HRs) and 95% Cls were estimated by Cox regression models adjusted for traditional risk factors defined by the Atherosclerosis Risk in Communities study HF risk score. During the 11.8-year follow-up, 5,502 incidents of HF occurred. Higher levels of circulating Lp(a), Lp(a) PRS, and positive FHx of CVD were associated with higher risks of HF. Compared with individuals who had lower circulating Lp(a) and no FHx, HRs (95% CIs) of HF were 1.36 (1.25, 1.49), 1.31 (1.19, 1.43), and 1.42 (1.22, 1.67) for those with higher Lp(a) and a positive history of CVD for all family members, parents, and siblings, respectively; similar results were observed by using Lp(a) PRS. The risk estimates for HF associated with elevated Lp(a) and positive FHx were attenuated after excluding those with incident myocardial infarction (MI) during follow-up. Lp(a) and FHx of CVD were independent risk factors for incident HF, and the highest risk of HF was observed among individuals with both risk factors. The association may be partly mediated by myocardial infarction.


Assuntos
Doenças Cardiovasculares , Insuficiência Cardíaca , Infarto do Miocárdio , Adulto , Humanos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/genética , Incidência , Lipoproteína(a)/genética , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/complicações , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/genética , Fatores de Risco
19.
Opt Lett ; 48(11): 3111-3114, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37262293

RESUMO

Quantum entanglement is an important pillar of quantum information processing. In addition to the entanglement degree, the bandwidth of entangled states becomes another focus of quantum communication. Here, by virtue of a broadband frequency-dependent beam splitter, we experimentally demonstrate six pairs of independent entangled sideband modes with maximum entanglement degree of 8.1 dB. Utilizing a time delay compensation scheme, the bandwidth of independent entangled sideband modes is expanded to dozens of megahertz. This work provides a valuable resource to implement efficient quantum information processing.

20.
ACS Appl Mater Interfaces ; 15(27): 32341-32351, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37379231

RESUMO

Promoting the catalyst performance for oxygen reduction reaction (ORR) in energy conversion devices through controlled manipulation of the structure of catalytic active sites has been a major challenge. In this work, we prepared Fe-N-C single-atom catalysts (SACs) with Fe-N5 active sites and found that the catalytic activity of the catalyst with shrinkable Fe-N5-C11 sites for ORR was significantly improved compared with the catalyst bearing normal Fe-N5-C12 sites. The catalyst C@PVI-(TPC)Fe-800, prepared by pyrolyzing an axial-imidazole-coordinated iron corrole precursor, exhibited positive shifted half-wave potential (E1/2 = 0.89 V vs RHE) and higher peak power density (Pmax = 129 mW/cm2) than the iron porphyrin-derived counterpart C@PVI-(TPP)Fe-800 (E1/2 = 0.81 V, Pmax = 110 mW/cm2) in 0.1 M KOH electrolyte and Zn-air batteries, respectively. X-ray absorption spectroscopy (XAS) analysis of C@PVI-(TPC)Fe-800 revealed a contracted Fe-N5-C11 structure with iron in a higher oxidation state than the porphyrin-derived Fe-N5-C12 counterpart. Density functional theory (DFT) calculations demonstrated that C@PVI-(TPC)Fe-800 possesses a higher HOMO energy level than C@PVI-(TPP)Fe-800, which can increase its electron-donating ability and thus help achieve enhanced O2 adsorption as well as O-O bond activation. This work provides a new approach to tune the active site structure of SACs with unique contracted Fe-N5-C11 sites that remarkably promote the catalyst performance, suggesting significant implications for catalyst design in energy conversion devices.

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