15 research outputs found

    High-Throughput Screening of Transition Metal Single-Atom Catalysts for Nitrogen Reduction Reaction

    Full text link
    The discovery of metals as catalytic centers for nitrogen reduction reactions has stimulated great enthusiasm for single-atom catalysts. However, the poor activity and low selectivity of available SACs are far away from the industrial requirement. Through the high throughout first principles calculations, the doping engineering can effectively regulate the NRR performance of b-Sb monolayer. Especially, the origin of activated N2 is revealed from the perspective of the electronic structure of the active center. Among the 24 transition metal dopants, Re@Sb and Tc@Sb showed the best NRR catalytic performance with a low limiting potential. The Re@Sb and Tc@Sb also could significantly inhibit HER and achieve a high theoretical Faradaic efficiency of 100%. Our findings not only accelerate discovery of catalysts for ammonia synthesis but also contribute to further elucidate the structure-performance correlations

    Light-Reinforced Key Intermediate for Anticoking To Boost Highly Durable Methane Dry Reforming over Single Atom Ni Active Sites on CeO<sub>2</sub>.

    Get PDF
    Dry reforming of methane (DRM) has been investigated for more than a century; the paramount stumbling block in its industrial application is the inevitable sintering of catalysts and excessive carbon emissions at high temperatures. However, the low-temperature DRM process still suffered from poor reactivity and severe catalyst deactivation from coking. Herein, we proposed a concept that highly durable DRM could be achieved at low temperatures via fabricating the active site integration with light irradiation. The active sites with Ni-O coordination (NiSA/CeO2) and Ni-Ni coordination (NiNP/CeO2) on CeO2, respectively, were successfully constructed to obtain two targeted reaction paths that produced the key intermediate (CH3O*) for anticoking during DRM. In particular, the operando diffuse reflectance infrared Fourier transform spectroscopy coupling with steady-state isotopic transient kinetic analysis (operando DRIFTS-SSITKA) was utilized and successfully tracked the anticoking paths during the DRM process. It was found that the path from CH3* to CH3O* over NiSA/CeO2 was the key path for anticoking. Furthermore, the targeted reaction path from CH3* to CH3O* was reinforced by light irradiation during the DRM process. Hence, the NiSA/CeO2 catalyst exhibits excellent stability with negligible carbon deposition for 230 h under thermo-photo catalytic DRM at a low temperature of 472 °C, while NiNP/CeO2 shows apparent coke deposition behavior after 0.5 h in solely thermal-driven DRM. The findings are vital as they provide critical insights into the simultaneous achievement of low-temperature and anticoking DRM process through distinguishing and directionally regulating the key intermediate species

    Illumination-Invariant Feature Point Detection Based on Neighborhood Information

    No full text
    Feature point detection is the basis of computer vision, and the detection methods with geometric invariance and illumination invariance are the key and difficult problem in the field of feature detection. This paper proposes an illumination-invariant feature point detection method based on neighborhood information. The method can be summarized into two steps. Firstly, the feature points are divided into eight types according to the number of connected neighbors. Secondly, each type of feature points is classified again according to the position distribution of neighboring pixels. The theoretical deduction proves that the proposed method has lower computational complexity than other methods. The experimental results indicate that, when the photometric variation of the two images is very large, the feature-based detection methods are usually inferior, while the learning-based detection methods performs better. However, our method performs better than the learning-based detection method in terms of the number of feature points, the number of matching points, and the repeatability rate stability. The experimental results demonstrate that the proposed method has the best illumination robustness among state-of-the-art feature detection methods

    Table_1_Primary pulmonary nuclear protein of the testis midline carcinoma: case report and systematic review with pooled analysis.docx

    No full text
    Nuclear protein of the testis (NUT) midline carcinoma (NMC) is a rare tumor, with particularly low incidence in the lungs, and a correspondingly poor prognosis. To determine the clinicopathological characteristics, outcomes, and prognostic factors of primary pulmonary NMC, a case was reported and a systematic review was performed. Twenty-nine records, including ours, involving 62 cases, were finally included. The median age at diagnosis was 29.5 years. At presentation, the most common symptoms at presentation were cough (47.50%) and chest/back pain (37.50%). In terms of diagnosis, 32.14% of NMC cases were identified through immunohistochemistry (IHC); However, a greater number of cases may be misdiagnosed initially, and ultimately, the diagnosis of NMC was confirmed through a combination of IHC and fluorescence in situ hybridization (FISH). Despite the clinical application of various chemotherapy-based treatments, the actual effectiveness remains unsatisfactory. Furthermore, Cox regression analysis of multiple factors identified male gender and concurrent presence of pleural effusion as indicators of shorter survival time in patients. These results emphasize the importance of increased diagnostic awareness among clinical and pathology practitioners concerning NMC. While there is currently no established standard for treating NMC, a treatment approach combining multiple methods shows promise for future research. Concurrently, clinical and foundational investigations addressing variables such as gender and the presence of pleural effusion may yield valuable insights into the diagnosis and treatment of NMC.</p

    Mechanistic insight into the active centers of single/dual-atom Ni/Fe-based oxygen electrocatalysts

    Full text link
    Single-atom catalysts with maximum metal utilization efficiency show great potential for sustainable catalytic applications and fundamental mechanistic studies. We here provide a convenient molecular tailoring strategy based on graphitic carbon nitride as support for the rational design of single-site and dual-site single-atom catalysts. Catalysts with single Fe sites exhibit impressive oxygen reduction reaction activity with a half-wave potential of 0.89 V vs. RHE. We find that the single Ni sites are favorable to promote the key structural reconstruction into bridging Ni-O-Fe bonds in dual-site NiFe SAC. Meanwhile, the newly formed Ni-O-Fe bonds create spin channels for electron transfer, resulting in a significant improvement of the oxygen evolution reaction activity with an overpotential of 270 mV at 10 mA cm−2. We further reveal that the water oxidation reaction follows a dual-site pathway through the deprotonation of *OH at both Ni and Fe sites, leading to the formation of bridging O2 atop the Ni-O-Fe sites

    Characterization, phylogenetic analysis, and pathogenicity of a novel genotype 2 porcine Enterovirus G

    No full text
    Enterovirus G belongs to the family Picornaviridae and are associated with a variety of animal diseases. We isolated and characterized a novel EV-G2 strain, CHN-SCMY2021, the first genotype 2 strain isolated in China. CHN-SCMY2021 is about 25 nm diameter with morphology typical of picornaviruses and its genome is 7341 nucleotides. Sequence alignment and phylogenetic analysis based on VP1 indicated that this isolate is a genotype 2 strain. The whole genome similarity between CHN-SCMY2021 and other EV-G genotype 2 strains is 78.3–86.4%, the greatest similarity is to EVG/Porcine/JPN/Iba26–506/2014/G2 (LC316792.1). Recombination analysis indicated that CHN-SCMY2021 resulted from recombination between 714,171/CaoLanh_VN (KT265894.2) and LP 54 (AF363455.1). Except for ST cells, CHN-SCMY2021 has a broad spectrum of cellular adaptations, which are susceptible to BHK-21, PK-15, IPEC-J2, LLC-PK and Vero cells. In piglets, CHN-SCMY2021 causes mild diarrhea and thinning of the intestinal wall. The virus was mainly distributed to intestinal tissue but was also found in heart, liver, spleen, lung, kidney, brain, and spinal cord. CHN-SCMY2021 is the first systematically characterized EV-G genotype 2 strain from China, our results enrich the information on the epidemiology, molecular evolution and pathogenicity associated with EV-G

    Porcine Deltacoronavirus (PDCoV) Entry into PK-15 Cells by Caveolae-Mediated Endocytosis

    No full text
    (1) Background: Porcine deltacoronavirus (PDCoV) is a newly emerged enteric virus affecting pig breeding industries worldwide, and its pathogenic mechanism remains unclear. (2) Methods: In this study, we preliminarily identified the endocytic pathway of PDCoV in PK-15 cells, using six chemical inhibitors (targeting clathrin-mediated endocytosis, caveolae-mediated endocytosis, macropinocytosis pathway and endosomal acidification), overexpression of dominant-negative (DN) mutants to treat PK-15 cells and proteins knockdown. (3) Results: The results revealed that PDCoV entry was not affected after treatment with chlorpromazine (CPZ), 5-(N-ethyl-N-isopropyl) amiloride (EIPA)or ammonium chloride (NH4Cl), indicating that the entry of PDCoV into PK-15 cells were clathrin-, micropinocytosis-, PH-independent endocytosis. Conversely, PDCoV infection was sensitive to nystatin, dynasore and methyl-&beta;-cyclodextrin (M&beta;CD) with reduced PDCoV internalization, indicating that entry of PDCoV into PK-15 cells was caveolae-mediated endocytosis that required dynamin and cholesterol; indirect immunofluorescence and shRNA interference further validated these results. (4) Conclusions: In conclusion, PDCoV entry into PK-15 cells depends on caveolae-mediated endocytosis, which requires cholesterol and dynamin. Our finding is the first initial identification of the endocytic pathway of PDCoV in PK-15 cells, providing a theoretical basis for an in-depth understanding of the pathogenic mechanism of PDCoV and the design of new antiviral targets
    corecore