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Synergistic Catalysis of Binary RuP Nanoclusters on Nitrogen-Functionalized Hollow Mesoporous Carbon in Hydrogen Production from the Hydrolysis of Ammonia Borane

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JOURNAL OF PHYSICAL CHEMISTRY LETTERS 2021年第1期12卷 696-703页

作者： Lv, Hao Wei, Ren Guo, xuwen Sun, Lizhi liu, Ben Sichuan Univ Coll Chem Chengdu 610064 Peoples R China Nanjing Normal Univ Jiangsu Collaborat Innovat Ctr Biomed Funct Mat Sch Chem & Mat Sci Jiangsu Key Lab New Power Batteries Nanjing 210023 Peoples R China

Exploring highly efficient nanocatalysts for hydrogen (H-2) production from catalytic hydrolysis of ammonia borane (AB) under ambient conditions and further unveiling their catalytic mechanism are of critical importance for renewable energy conversion technologies but remain big challenges. Herein, ultrafine binary RuP alloy nanoclusters homogeneously encapsulated onto nitrogen-functionalized hollow mesoporous carbon supports (RuP@NHMCs) are reported as a high-performance platinum (Pt)-free nanocatalyst for catalytic hydrolysis of AB at room temperature. Remarkable catalytic activity with a very high turnover frequency of 1774 mol(H2) mol(Ru)(-1) min(-1) and a low activation energy of 36.3 kJ mol(-1) is observed based on compositional and structural synergies of RuP@NHMCs. Results of control experiments and catalytic kinetics studies reveal that the rate-determining step of catalytic hydrolysis of AB is the oxidation cleavage of a covalently stable H-OH bond, while RuP@NHMCs result in multiple electronic, functional, size, and support effects that kinetically accelerate the cleavage of attacked H-OH. Furthermore, RuP@NHMCs exhibit a good catalytic activity with a high yield of >99% for tandem hydrogenation of nitroarenes coupled with the hydrolysis of AB. We strongly believe that the catalyst design principle reported here could provide a new opportunity for synthesizing other Pt-free high-performance nanocatalysts.

关键词： Catalysts Catalytic activity Nanoclusters Hydrolysis Nanocatalysts

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A Curved Four-Conductor Assembly with Larger Uniform Region

A Curved Four-Conductor Assembly with Larger Uniform Region

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2023 Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium, EFTF/IFCS 2023

作者： Li, Chao Hu, xuwen Sun, Fuyu liu, Jie Li, Xiaofeng Zhang, Shougang National Time Service Center Chinese Academy of Sciences Xi'an China University of Chinese Academy of Sciences Beijing China

ISBN: (纸本)9798350311426

Most atomic physics setups require a uniform static magnetic field to define a quantization axis. The straight four-conductor assembly has been proven to be a useful structure for producing such a uniform static magnetic field. Here, we present an improved four-conductor assembly, where each conductor consists of one straight section and two curved sections. This hybrid structure arrangement offers more degrees of freedom than the conventional straight four-conductor assembly, enabling a larger uniform field region and better field spatial uniformity. The modified magnetic field generation structure can be used in many fields of atomic precision spectroscopy. © 2023 IEEE.

关键词： curved section four-conductor modified four-conductor static magnetic field uniformity

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Characterisation of Ti(C, N)-based cermets with various nitrogen contents studied by EBSD/SEM and TEM

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JOURNAL OF ALLOYS AND COMPOUNDS 2017年 695卷 2857-2864页

作者： Shi, Zengmin Yin, Dezheng Zhang, Dayong liu, xuwen China Three Gorges Univ Coll Mat & Chem Engn Yichang 443002 Peoples R China Tianjin Recommend Sci & Technol Dev Co Ltd Tianjin 300050 Peoples R China

Ti(C, N)-based cermets with different N/(C + N) ratios were prepared by vacuum sintering. The effect of nitrogen content on microstructure of Ti(C, N) based cermets was analyzed using a combination of the electron backscatter diffraction in a scanning electron microscope (EBSD/SEM) and transmission electron microscope (TEM). The combination of XRD and SEM/BSE effectively showed the influence of the carbon and nitrogen contents on the core/rim microstructure features. EBSD maps gave a vivid image for hard phase grains, especially the carbonitride grain size distribution, orientation distribution and crack propagation. The combination of EBSD/SEM and TEM revealed a highly coherent interface between the core and rim. The carbonitride particle and the binder had a large high angle boundary and a coherent interface. A constant interface orientation of the carbonitride particle and binder was characterized. The major factors determining the transverse rupture strength and the fracture toughness were discussed in terms of the crack propagation. (C) 2016 Elsevier B. V. All rights reserved.

关键词： Ti(C, N)-based cermet EBSD Orientation Nitrogen content Structure

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Correction of Read Biases Induced by Complex Reference Genome Regions for Improving Copy Number Variation Detection Using a Gaussian Mixture Model

Correction of Read Biases Induced by Complex Reference Genom...

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2024 IEEE International Conference on Bioinformatics and Biomedicine, BIBM 2024

作者： Wang, xuwen Chang, Zhili Wang, Shenjie liu, Ruoyu liu, Yuqian Zhu, Xiaoyan Shao, Yang Lai, Xin Yang, Shuanying Wang, Jiayin Second Affiliated Hospital Xi'an Jiaotong University Department of Respiratory Medicine Xi'an710003 China Xi'an Jiaotong University School of Computer Science and Technology Xi'an710049 China Xi'an Jiaotong University Shaanxi Engineering Research Center of Medical and Health Big Data Xi'an710049 China Nanjing Geneseeq Technology INC. China

ISBN: (纸本)9798350386226

Copy number variations are crucial in cancer research, but their detection through next-generation sequencing is often hindered by read biases, particularly in complex genomic regions. Existing bias-correction methods address common issues like GC content but often fail in regions with repetitive sequences or segmental duplications, leading to false-positive CNVs. We propose refMask, a hybrid Gaussian model-based method that dynamically identifies low-confidence regions in the reference genome, correcting read biases and improving CNV detection accuracy. By integrating features from hg38 and T2T genomes, refMask tailors a custom blacklist for each sequencing sample, enhancing the reliability of CNV detection across diverse conditions. Our method provides a more accurate and flexible solution compared to current fixed blacklists, offering improved performance in challenging genomic regions. © 2024 IEEE.

关键词： Copy number variation Gaussian model Next-generation sequencing Read biase

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A pH and Temperature Dual-Responsive Microgel-Embedded, Adhesive, and Tough Hydrogel for Drug Delivery and Wound Healing

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ACS APPLIED MATERIALS & INTERFACES 2023年第15期15卷 19560-19573页

作者： Peng, xuwen Peng, Qian Wu, Meng Wang, Wenda Gao, Yongfeng liu, Xiong Sun, Yongxiang Yang, Diling Peng, Qiongyao Wang, Tao Chen, Xing-Zhen liu, Jifang Zhang, Hao Zeng, Hongbo Univ Alberta Dept Chem & Mat Engn Edmonton AB 619 Canada Guangzhou Med Univ Affiliated Hosp 5 Guangzhou 510700 Guangdong Peoples R China Univ Alberta Fac Med & Dent Dept Physiol Edmonton AB 627 Canada

Stimuli-responsive hydrogels have attracted much attention over the past decade for potential bioengineering applications such as wound dressing and drug delivery. In this work, a pH and temperature dual-responsive microgel-embedded hydrogel has been fabricated by incorporating poly(N-isopropylacrylamide-co-acrylic acid) (PNIPAAm-co-AAc) based microgel particles into polyacrylamide (PAAm)/chitosan (CS) semi-interpenetrating polymer network (semi-IPN), denoted as microgel@PAM/ CS. The resultant hydrogel possesses excellent mechanical properties including stretchability, compressibility, and elasticity. In addition, the microgel@PAM/CS hydrogels can tightly adhere to the surfaces of a variety of tissues such as porcine skin, kidney, intestine, liver, and heart. Moreover, it shows controlled dual-drug release profile of both bovine serum albumin (BSA) (as a model protein) and sulfamethoxazole (SMZ), an antibiotic. Excellent antimicrobial properties are obtained for SMZ-loaded microgel@ PAM/CS hydrogels. Compared with traditional drug administration methods such as by mouth, injection, and inhalation, the microgel@PAM/CS hydrogels possess advantages such as higher drug loading efficiency (by more than 80%) and controllable and sustained (over 48 h) release. The microgel@PAM/ CS hydrogels can significantly enhance the wound healing process. This work provides a facile approach for the fabrication of multifunctional stimuli-responsive microparticle-embedded hydrogels with semi-IPN structures, and the as-prepared microgel@ PAM/CS hydrogels have great potential for applications as smart wound dressing materials in biomedical engineering.

关键词： stimuli-responsive hydrogel multifunctional hydrogel interfacial interaction drug delivery wound dressing

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Thermal-mechanical coupling in drilling high-performance CFRP: Scale-span modeling and experimental validation

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COMPOSITE STRUCTURES 2024年 331卷

作者： liu, Yong Pan, Zitao Zhang, Hao Jing, xuwen Zhou, Honggen Chen, Yong Jiangsu Univ Sci & Technol Coll Mech Engn Zhenjiang 212003 Peoples R China Yancheng Inst Technol Sch Automot Engn Yancheng 224051 Peoples R China

The focus of this study is to explore a scale -span thermal-mechanical coupling method for predicting the dynamic mechanical progressive failure behaviors and predicting thermal damage during the drilling process of Carbon Fiber Reinforced Plastic (CFRP). Initially, a thermal conduction constitutive model of drilling CFRP was developed based on the proposed thermal distribution ratio calculation method. Meanwhile, a dynamic spanscale progressive damage constitutive model for CFRP, incorporating modified micromechanics failure criterion with bilinear damage evolution laws, was proposed, and a bilinear cohesive model, including three damage modes, is employed to simulate interlaminar delamination. Subsequently, a user -defined material subroutine VUMAT was implemented on the ABAQUS/Explicit platform to simulate the thermal-mechanical coupling behaviors of drilling T700S-12K/YPH-23 CFRP using a twist drill bit. Finally, a comprehensive information monitoring platform for CFRP drilling experiments was established to validate the accuracy of the simulation results by considering drilling temperature, thrust force, and hole -wall morphology. The results demonstrate excellent agreement between the established thermal-mechanical coupling span -scale model and the experimental data. Furthermore, the simulation effectively captures the various damage behaviors and thermal conduction phenomenon, that occur during the intact drilling process.

关键词： CFRP Drilling Scale -span Thermal -mechanical coupling Progressive failure

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Asymmetry of inferior turbinate in patients with nasal septum deviation and its significance for nasal ventilation surgery

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EUROPEAN ARCHIVES OF OTO-RHINO-LARYNGOLOGY 2021年第5期279卷 2423-2431页

作者： liu, Jinfeng Qian, Zhuoming Yan, Zhanfeng Yang, xuwen Wang, Ningyu Capital Med Univ Beijing Chaoyang Hosp Dept Otorhinolaryngol Head & Neck Surg 8 Gongti South Rd Beijing 100020 Peoples R China Univ Chinese Acad Sci Beijing Huairou Dept Otorhinolaryngol Beijing 101400 Peoples R China Beijing Univ Chinese Med Dongzhimen Hosp Dept Otorhinolaryngol Beijing 100700 Peoples R China Capital Med Univ Clin Med Sch 3 7 Med Students Long Schooling Class 3 Beijing 100020 Peoples R China

Purpose To investigate the asymmetry of the inferior turbinate (IT) in patients with nasal septum deviation (NSD). Methods The paranasal sinus computed tomography (CT) of 100 patients with NSD were retrospectively investigated from February 2018 to December 2019. The thickness of IT, IT mucosa and IT bone, the distance between the IT and the midline were measured on both the concave and convex sides, and which correlation with NSD was analyzed. Results The widths of the IT, IT bone and IT medial mucosa on the concave side were larger than those on the convex side (all P < 0.05). The distance from the IT and IT bone to the midline on the concave side was smaller than those on the convex side (P < 0.05, respectively). The degree of NSD had a negative correlation with the widths of the IT and IT bone on the convex side, and the distance between the IT and the midline on the concave side;and a positive correlation with the distance from IT and IT bone to the midline on the convex side, and IT mucosa thickness on the concave side (all P < 0.05). Conclusion The asymmetric IT width is mainly caused by both hypertrophies of the IT mucosa on the concave side and atrophy of the IT bone on the convex side. Therefore, during the surgery of nasal ventilation reconstruction, the IT on the convex side are suggested to be protected from intervention. In contrast, it is necessary to lateralize the IT bone and reduce the IT submucosal tissue on the concave side. However, routine excision of the IT bone is not recommended.

关键词： Nasal septum deviation Inferior turbinate Nasal obstruction Septoplasty Inferior turbinate hypertrophy

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Effect of Fe–N–C single atom/cluster catalyst on ORR of PEMFC

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International Journal of Hydrogen Energy 2025年 139卷 718-729页

作者： Li, Ruina Li, xuwen liu, Qingcheng Yue, Hua Meng, Yang Tian, Yuanyuan School of Automotive and Traffic Engineering Jiangsu University Jiangsu Zhenjiang212013 China Research Center of Fluid Machinery Engineering and Technology Jiangsu University Jiangsu Zhenjiang212013 China Zhejiang Shaoxing312000 China Key Laboratory of Chemical Additives for China National Light Industry College of Chemistry and Chemical Engineering Shaanxi University of Science and Technology Shaanxi Xi'an710021 China

With the continuous advancement of fuel cell technology, the exploration and development of highly efficient non - precious - metal catalysts for the oxygen reduction reaction (ORR) have emerged as a focal point of research. Fe–N–C catalysts have attracted much attention due to their excellent performance and low cost, and coupling single-atom catalysts (SACs) with atomic clusters (ACs) is an effective method to improve catalyst activity. This study used the pyrolysis method to synthesize iron atom catalysts (Fe–N–C SACs) and iron cluster coupled catalysts (Fe–N–C SACs/ACs) on ZIF-8 carbon support. It evaluated the catalyst performance through electrochemical testing. The experimental results showed that the introduction of Fe clusters improved the half-wave potential of the catalyst to 0.399 V, which represented an 8.2 % enhancement compared to the SAC catalyst and reached 87.1 % of that of the commercial Pt–C catalyst, and reduced the Tafel slope to 61.47 mV dec−1, effectively improving the ORR activity of the catalyst. We constructed FeN4 single atom catalyst models and FeN4/Fe4N6 single atom cluster catalyst models using density functional theory (DFT), analyzed their electronic structures and reaction mechanisms, and revealed the mechanism of action of iron clusters. DFT calculations showed that iron clusters altered the charge distribution of FeN4 sites, reducing the rate determining step (RDS) (OH desorption) energy to 0.5 eV, which promoted the desorption of products and the re-adsorption of reactants. As a result, the superior electrocatalytic performance of Fe–N–C SAC/AC is attributed to the synergistic effect between iron clusters and single atoms, which is influenced by the coordination environment and provides new ideas for designing efficient ORR catalysts. © 2025 Hydrogen Energy Publications LLC

关键词： Electrolytic reduction

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Identifying key elements for evidence-base medicine using pretrained model and graph convolution network 10

Identifying key elements for evidence-base medicine using pr...

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10th International Conference on Information Technology and Quantitative Management, ITQM 2023

作者： Yang, Fengchun Xu, Xiaowei Wu, Meng Wang, xuwen She, liu Qian, Qing Li, Jiao Institute of Medical Information Chinese Academy of Medical Sciences Peking Union Medical College Beijing100020 China Key Laboratory of Medical Information Intelligent Technology Chinese Academy of Medical Sciences Beijing100020 China

Objective: Evidence-based medicine (EBM) provides a framework to support clinicians' decision-making processes using the best evidence currently available in the field. The key elements of clinical research can be defined by a framework called PICO, which identifies the sentences in a medical literature text that belong to the four key elements reported in clinical trials: Participants/Problem (P), Intervention (I), Comparison (C) and Outcome (O). This study aims to establish an effective detection method for key elements of evidence-based medical research. Methods: Based on the text features of key elements framework, we propose a deep learning model BERTGCN which combined large-scale pretraining model and graph convolution network (GCN) for detecting key elements of evidence-based medicine. In this model, the sentences which are initialized with pre-trained BERT representations and the words in the EBM evidence were recognized as the sentence nodes and word of the graph which were used to train GCN model. At the same time, the sentences were used to fine tune the pretraining model. Results: We tested our proposed approach over PubMed-PICO dataset is a data set containing tens of thousands of EBM key elements extracted from PubMed. The F1-score of P/I/O in the model we proposed reached 91.3%, 85.8% and 90.0% respectively. Experimental results show that our model outperforms the current optimal model. Conclusions: BERTGCN is able to leverage the advantages of both worlds: large-scale pretraining and transudative learning to improve the efficiency of detecting evidence-based medical evidence from research publications. © 2023 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://***/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the Tenth International Conference on Information Technology and Quantitative Management.

关键词： Convolution

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Submarine Continental Slopes Stability Prediction of Natural Gas HydratesBased on Machine Learning

Submarine Continental Slopes Stability Prediction of Natural...

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Offshore Technology Conference, OTC 2025

作者： Chen, Yu He, Yufa Wang, Yixuan Zhou, Yunjian Fu, Qiang Qin, xuwen liu, Dingyuan Tian, Zheng Zhang, Kexin CNOOC Research Institute Ltd State Key Laboratory of Offshore Natural Gas Hydrates Beijing China Huairou Laboratory Beijing China China Aero Geophysical Survey and Remote Sensing Center for Natural Resources Beijing China

ISBN: (纸本)9781959025610

In the process of extracting naturally-occurring oceanic gas hydrates, the dissociation of hydrates can causea reduction in soil strength. This reduction has the potential to trigger slope failure and submarine landslides,which present a catastrophic threat to offshore facilities and hydrate production. This research aims to create a robust and accurate machine-learning model that can efficiently predict stability of submarine continental slopes where gas hydrates are widespread. By collecting and analyzing 144 relevant cases, a comprehensive dataset was constructed, incorporating slope basic data, overlying and underlying layer data, and geological parameters of the hydrate layer. After conducting a correlation coefficient analysis between the characteristic parameters of the dataset and the output, the key characteristic parameters were determined. To model the dataset and assess its performance, four machine learning techniques were employed: Random Forest(RF), XGBoost, K-Nearest Neighbors (KNN), and Support Vector Machine (SVM). Formation physical parameters, geotechnical parameters, and NGH parameters were taken as input parameters, and the stability of NGH slopes was taken as prediction indicator. Evaluation metrics such as the ROC and confusion matrix were employed to comprehensively evaluate these models’ classification ability. Among these algorithms,the RF algorithm achieves the best prediction accuracy and AUC value, demonstrating its potential in submarine continental slopes stability prediction of natural gas hydrates. Additionally, sensitive analysis using Gini impurity calculations revealed that hydrate decomposition degree is the most significant factor affecting slope stability, followed by the burial depth and thickness of the hydrate layer. The slope angle,cohesion, and internal friction angle also have significant impacts. This study provides a new perspective for predicting submarine continental slopes stability with NGH and offers a scientific

关键词： Landslides

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