An electrocatalytic methanol oxidation reaction (MOR) is proposed to replace oxygen evolution reaction (OER) in water electrolysis owing to the favorable thermodynamics of MOR than OER. However, there is still a compe...
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An electrocatalytic methanol oxidation reaction (MOR) is proposed to replace oxygen evolution reaction (OER) in water electrolysis owing to the favorable thermodynamics of MOR than OER. However, there is still a competition between the MOR and the OER when the applied potential is in the conventional OER zone. How to inhibit OER while maintaining efficient MOR is an open and challenging question, and there are few reports focusing on this thus far. Herein, by taking NiFe layered double hydroxide (LDH) as a model catalyst due to its intrinsically high catalytic activity for the OER, the perspective of inhibiting OER is shown and thus promoting MOR through a heterogenous engineering of NiFe-LDH. The engineered heterostructure comprising NiFe-LDH and in situ formed NiFe-hexylaminobenzene (NiFe-HAB) coordination polymer exhibits outstanding electrocatalytic capability for methanol oxidation to formic acid (e.g., the Faradaic efficiencies (FEs) of formate product are close to 100% at various current densities, all of which are much larger than those (53-65%) on unmodified NiFe-LDH). Mechanism studies unlock the modification of NiFe-HAB passivates the OER activity of NiFe-LDH through tailoring the free energies for element reaction steps of the OER and increasing the free energy of the rate-determining step, consequently leading to efficient MOR.
For exploratory data analysis, it is often desirable to know what answers you are likely to get before actually obtaining those answers. This can potentially be achieved by designing systems to offer the estimates of ...
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BackgroundThe cytological diagnostic process of EUS-FNA smears is time-consuming and manpower-intensive, and the conclusion could be subjective and controversial. Moreover, the relative lack of cytopathologists has li...
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BackgroundThe cytological diagnostic process of EUS-FNA smears is time-consuming and manpower-intensive, and the conclusion could be subjective and controversial. Moreover, the relative lack of cytopathologists has limited the widespread implementation of Rapid on-site evaluation (ROSE) presently. Therefore, this study aimed to establish an AI system for the detection of pancreatic ductal adenocarcinoma (PDAC) based on EUS-FNA cytological *** collected 3213 unified magnification images of pancreatic cell clusters from 210 pancreatic mass patients who underwent EUS-FNA in four hospitals. A semi-supervised CNN (SSCNN) system was developed to distinguish PDAC from Non-PDAC. The internal and external verifications were adopted and the diagnostic accuracy was compared between different seniorities of cytopathologists. 33 images of "Atypical" diagnosed by expert cytopathologists were selected to analyze the consistency between the system and definitive *** segmentation indicators Mean Intersection over Union (mIou), precision, recall and F1-score of SSCNN in internal and external testing sets were 88.3%, 93.21%,94.24%, 93.68% and 87.75%, 93.81%, 93.14%, 93.48% successively. The PDAC classification indicators of the SSCNN model including area under the ROC curve (AUC), accuracy, sensitivity, specificity, PPV and NPV in the internal testing set were 0.97%, 0.95%, 0.94%, 0.97%, 0.98%, 0.91% respectively, and 0.99%, 0.94%, 0.94%, 0.95%, 0.99%, 0.75% correspondingly in the external testing set. The diagnostic accuracy of senior, intermediate and junior cytopathologists was 95.00%, 88.33% and 76.67% under the binary diagnostic criteria of PDAC and non-PDAC. In comparison, the accuracy of the SSCNN system was 90.00% in the dataset of man-machine competition. The accuracy of the SSCNN model was highly consistent with senior cytopathologists (Kappa = 0.853, P = 0.001). The accuracy, sensitivity and specificity of the system in the classification of "a
Monolayered Ni-based layered double hydroxides (LDHs) enriched with hydroxyl vacancies are syn-thesized and first applied in the methanol-assisted energy-saving hydrogen production system including independent electro...
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Monolayered Ni-based layered double hydroxides (LDHs) enriched with hydroxyl vacancies are syn-thesized and first applied in the methanol-assisted energy-saving hydrogen production system including independent electrolysis and photovoltaic-electrolysis. The rich hydroxyl vacancies are revealed to endow monolayered LDHs with significantly superior performance in the aspects of the activity for methanol oxidation reaction and the boosting effect for cathodic hydrogen production compared to the bulk counterparts. The theoretical and experimental results confirm that the hydroxyl vacancies can increase density of states near Fermi level of LDH (i.e. elevate electrical conductivity to form favorable charge transportation during electrocatalysis), and promote its adsorption and further cleavage for methanol, thus leading to the enhanced methanol oxidation reaction performance.(c) 2022 Elsevier Ltd. All rights reserved.
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