56 results on '"Wang, Xiaokang"'
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2. Latent Profiles of Coronavirus-Related Health Literacy in Chinese Residents and Its Related Predictors
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Du, Yawen, Wang, Xiaokang, Bu, Xiaoou, Hu, Fawen, Long, Junwei, and Wang, Pei
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- 2024
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3. Thiadiazole-Functionalized Th/Zr-UiO-66 for Efficient C2H2/CO2Separation
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Wang, Xiaokang, Liu, Hongyan, Sun, Meng, Wang, Haoyang, Feng, Xueying, Chen, Wenmiao, Feng, Xiang, Fan, Weidong, and Sun, Daofeng
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Adsorptive separation technology provides an effective approach for separating gases with similar physicochemical properties, such as the purification of acetylene (C2H2) from carbon dioxide (CO2). The high designability and tunability of metal–organic framework (MOF) adsorbents make them ideal design platforms for this challenging separation. Herein, we employ an isoreticular functionalization strategy to fine-tune the pore environment of Zr- and Th-based UiO-66 by the immobilization of the benzothiadiazole group via bottom-up synthesis. The functionalized UPC-120 exhibits an enhanced C2H2/CO2separation performance, which is confirmed by adsorption isotherms, dynamic breakthrough curves, and theoretical simulations. The synergy of ligand functionalization and metal ion fine-tuning guided by isoreticular chemistry provides a new perspective for the design and development of adsorbents for challenging gas separation processes.
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- 2024
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4. Industrial Metaverse for Smart Manufacturing: Model, Architecture, and Applications
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Ren, Lei, Dong, Jiabao, Zhang, Lin, Laili, Yuanjun, Wang, Xiaokang, Qi, Yue, Li, Bo Hu, Wang, Lihui, Yang, Laurence T., and Deen, M. Jamal
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Smart manufacturing has been transforming toward industrial digitalization integrated with various advanced technologies. Metaverse has been evolving as a next-generation paradigm of a digital space extended and augmented by reality. In the metaverse, users are interconnected for various virtual activities. In consideration of advanced possibilities that may be brought by the metaverse, it is envisioned that industrial metaverse should be integrated into smart manufacturing to upgrade industry for more visible, intelligent and efficient production in the future. Therefore, a conceptual model, named IMverse Model, and novel characteristics of the industrial metaverse for smart manufacturing are proposed in this article. Besides, an industrial metaverse architecture, named IMverse Architecture, is proposed involving several key enabling technologies. Typical innovative applications of the industrial metaverse throughout the whole product life cycle for smart manufacturing are presented with insights. Nonetheless, in prospect of future, the industrial metaverse still faces limitations and is far from implementation. Thus, challenges and open issues of the industrial metaverse for smart manufacturing are discussed, then outlook is provided for further research and application.
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- 2024
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5. An Intelligent Edge-Cloud Collaborative Framework for Communication Security in Distributed Cyber-Physical Systems
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Chen, Cen, Li, Yangfan, Wang, Qinyu, Yang, Xulei, Wang, Xiaokang, and Yang, Laurence T.
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The rapid growth of IoT (Internet of Things) and smart services facilitate many CPS (Cyber-Physical Systems) such as smart health, smart grid and so on. Nevertheless, the communication security issues in CPS are becoming more and more important with the growing complexity of the CPS network and the increasing dependency of critical network infrastructure on cyber-based technologies. In recent years, deep learning technology has shown its superiority in detecting communication security attacks, but its high computational complexity and the massive amount of data generated by IoT devices have brought challenges to traditional cloud computing technology in terms of bandwidth and computing resources. In this paper, we have analyzed the characteristics of heterogeneity and hierarchy in attacks on CPS. We have also analyzed the role of edge intelligence in handling the security of large-scale data communication in CPS. Furthermore, we proposed a CPS communication attack detection framework based on edge cloud collaboration, aiming to improve the parallel efficiency of hardware resources when executing detection tasks. We aim to enhance the intelligence of physical devices and the degree of cloud collaboration, satisfying the real-time processing requirements of large-scale, hierarchical CPS attack detection. Furthermore, through simple simulation experiments, we verified the effectiveness of the proposed edge cloud collaboration framework in CPS attack detection.
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- 2024
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6. A Multidimensional Tensor Low Rank Method for Magnetic Resonance Image Denoising
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Deng, Lizhen, Cao, Yuxin, Wang, Zhongyang, Wang, Xiaokang, and Wang, Yu
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In this paper, we present the Magnetic Resonance Image (MRI) denoising method via nonlocal multidimensional low rank tensor transformation constraint (NLRT). We first design a nonlocal MRI denoising method by non-local low rank tensor recovery framework. Furthermore, a multidimensional low rank tensor constraint is used to obtain low-rank prior information combined with 3-dimensional structure feature of MRI image cubes. Our NLRT can achieve denoising by retaining more image detail information. The optimization and updating process of the model is solved via the alternating direction method of multipliers (ADMM) algorithm. Several state-of-the-art denoising methods are selected for comparative experiments. In order to reflect the performance of the denoising method, Rician noise with different levels is added to the experiment to analyze the results. The experimental results prove that our NLTR has more outstanding denoising ability and can obtain better MRI images.
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- 2024
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7. QTT-DLSTM: A Cloud-Edge-Aided Distributed LSTM for Cyber–Physical–Social Big Data
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Wang, Xiaokang, Ren, Lei, Yuan, Ruixue, Yang, Laurence T., and Deen, M. Jamal
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Cyber–physical–social systems (CPSS), an emerging cross-disciplinary research area, combines cyber–physical systems (CPS) with social networking for the purpose of providing personalized services for humans. CPSS big data, recording various aspects of human lives, should be processed to mine valuable information for CPSS services. To efficiently deal with CPSS big data, artificial intelligence (AI), an increasingly important technology, is used for CPSS data processing and analysis. Meanwhile, the rapid development of edge devices with fast processors and large memories allows local edge computing to be a powerful real-time complement to global cloud computing. Therefore, to facilitate the processing and analysis of CPSS big data from the perspective of multi-attributes, a cloud-edge-aided quantized tensor-train distributed long short-term memory (QTT-DLSTM) method is presented in this article. First, a tensor is used to represent the multi-attributes CPSS big data, which will be decomposed into the QTT form to facilitate distributed training and computing. Second, a distributed cloud-edge computing model is used to systematically process the CPSS data, including global large-scale data processing in the cloud, and local small-scale data processed at the edge. Third, a distributed computing strategy is used to improve the efficiency of training via partitioning the weight matrix and large amounts of input data in the QTT form. Finally, the performance of the proposed QTT-DLSTM method is evaluated using experiments on a public discrete manufacturing process dataset, the Li-ion battery dataset, and a public social dataset.
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- 2023
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8. Synthesis and emergent properties of structurally complex materials with nonrandom disorder
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Wang, Xiaokang, Li, Jiahui, and Chen, Qian
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This preview discusses the emergent new paradigm of structural complexity engineering, featuring two recent studies on an aperiodic metal-organic framework and nanoassembly of a symmetry-breaking chiral continuum bowtie. These structurally complex materials are not ordered but also not completely random, with controlled lowered symmetry.
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- 2023
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9. Ortho Effects of Tricarboxylate Linkers in Regulating Topologies of Rare-Earth Metal–Organic Frameworks
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Li, Fugang, Wang, Kun-Yu, Liu, Zhengyang, Han, Zongsu, Kuai, Dacheng, Fan, Weidong, Feng, Liang, Wang, Yutong, Wang, Xiaokang, Li, Yue, Yang, Zhentao, Wang, Rongming, Sun, Daofeng, and Zhou, Hong-Cai
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A linker design strategy is developed to attain novel polynuclear rare-earth (RE) metal–organic frameworks (MOFs) with unprecedented topologies. We uncover the critical role of ortho-functionalized tricarboxylate ligands in directing the construction of highly connected RE MOFs. The acidity and conformation of the tricarboxylate linkers were altered by substituting with diverse functional groups at the ortho position of the carboxyl groups. For instance, the acidity difference between carboxylate moieties resulted in forming three hexanuclear RE MOFs with novel (3,3,3,10,10)-c wxl, (3,12)-c gmx, and (3,3,3,12)-c joetopologies, respectively. In addition, when a bulky methyl group was introduced, the incompatibility between the net topology and ligand conformation guided the co-appearance of hexanuclear and tetranuclear clusters, generating a novel 3-periodic MOF with a (3,3,8,10)-c kywnet. Interestingly, a fluoro-functionalized linker prompted the formation of two unusual trinuclear clusters and produced a MOF with a fascinating (3,8,10)-c lfgtopology, which could be gradually replaced by a more stable tetranuclear MOF with a new (3,12)-c leetopology with extended reaction time. This work enriches the polynuclear clusters library of RE MOFs and unveils new opportunities to construct MOFs with unprecedented structural complexity and vast application potential.
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- 2023
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10. Analysis of the Characteristics of the Low-level Jets in the Middle Reaches of the Yangtze River during the Mei-yu Season
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Cui, Chunguang, Zhou, Wen, Yang, Hao, Wang, Xiaokang, Deng, Yi, Wang, Xiaofang, Xu, Guirong, and Wang, Jingyu
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Here, we analyze the characteristics and the formation mechanisms of low-level jets (LLJs) in the middle reaches of the Yangtze River during the 2010 mei-yu season using Wuhan station radiosonde data and the fifth generation of the European Centre for Medium-Range Weather Forecasts (ERA5) reanalysis dataset. Our results show that the vertical structure of LLJs is characterized by a predominance of boundary layer jets (BLJs) concentrated at heights of 900–1200 m. The BLJs occur most frequently at 2300 LST (LST=UTC+ 8 hours) but are strongest at 0200 LST, with composite wind velocities >14 m s−1. Synoptic-system-related LLJs (SLLJs) occur most frequently at 0800 LST but are strongest at 1100 LST, with composite wind velocities >12 m s−1. Both BLJs and SLLJs are characterized by a southwesterly wind direction, although the wind direction of SLLJs is more westerly, and northeasterly SLLJs occur more frequently than northeasterly BLJs. When Wuhan is south of the mei-yu front, the westward extension of the northwest Pacific subtropical high intensifies, and the low-pressure system in the eastern Tibetan Plateau strengthens, favoring the formation of LLJs, which are closely related to precipitation. The wind speeds on rainstorm days are greater than those on LLJ days. Our analysis of four typical heavy precipitation events shows the presence of LLJs at the center of the precipitation and on its southern side before the onset of heavy precipitation. BLJs were shown to develop earlier than SLLJs.
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- 2023
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11. Custom Grasping: A Region-Based Robotic Grasping Detection Method in Industrial Cyber-Physical Systems
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Laili, Yuanjun, Chen, Zelin, Ren, Lei, Wang, Xiaokang, and Deen, M. Jamal
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Industrial Cyber Physical Systems can use data and information gained from across a variety of different environments to enable robots that are reconfigurable. Custom grasping is a basic operation a robot must be able to carry out for a given task, i.e., finding the best grasping point for emergent behaviors. However, environmental disturbance and limited data degrade the precision and speed of many tailored machine learning models on robot grasping detection. This paper proposes a region-based method to enable fast custom grasping through fewer RGB-D data. The grasping detection problem is simplified as a two-stage prediction problem. At the first stage, a robust grasp candidate generation strategy is proposed based on the Sobel operator. At the second stage, a region-based predictor is designed to locate the best grasping point-pair for an emergent task. The predictor is trained by a modified consistency based self-training method to realize semi-supervised learning. Experimental results show that the success rate of custom grasping of new emergent object can be increased by 3.4% on average using the proposed method. By introducing data augmentation strategies in training, the success rate is further increased by 9.2% on average. A robot is able to grasp new object with 91.5% success rate using less than 100 training samples. The number of training samples required for the proposed method is less than to 1% of which for the previous works. Note to Practitioners—This research was motivated by the problem of robot reconfigurability for various industrial automation processes and focuses mainly on the recognition of grasping point-pair of emergent object for different task. Existing approaches on robotic grasping detection are tailored to a given object and require expensive training with large amount of labeled data. This paper presents a region-based few shot learning approach that enables the robot to detect the best grasping point-pair autonomously and quickly. We show how to generate candidate point-pairs with image distortion and background disturbance. We then demonstrate how the best grasping point-pair can be located with much less training cost. Experiments suggest that this approach is feasible in robot automation for handling a class of objects. In future research, we will construct behavior learning module to enable evolving cyber-physical robotic system for more purposes.
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- 2023
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12. Pathogen Distribution and Antimicrobial Resistance of Early Onset Sepsis in Very Premature Infants: A Real-World Study
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Ji, Hongyan, Yu, Yonghui, Huang, Lei, Kou, Yan, Liu, Xin, Li, Shina, Zhang, Yongfeng, Li, Zhongliang, Sun, Xuemei, Wang, Jing, Yang, Kun, Zhou, Liying, Luo, Yao, Zhao, Guoying, Yang, Zhenying, Zhang, Xiao, Cui, Xiujie, Li, Jing, Wang, Ying, Shi, Jing, Chen, Weibing, Ma, Yanying, Zhao, Peng, Zhao, Riming, Zhou, Kun, Li, Binghui, Zhu, Renxia, Gao, Yanling, Zhou, Zhiyuan, Li, Huan, Dou, Jinlan, Li, Haiyan, Zhao, Changliang, Zhang, Bingjin, and Wang, Xiaokang
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Introduction: Early onset sepsis (EOS) remains a potentially fatal newborn condition, especially in very preterm infants. Data on the pathogen distribution and antibiotic susceptibility patterns of EOS among very preterm infants are scarce but essential for the choice of empirical antibiotic administration. We sought to assess the epidemiologic characteristics and antibiotic susceptibility patterns of pathogens causing EOS among a cohort of very preterm infants in China. Methods: This prospective, observational study included a cohort of infants born at a gestational age (GA) less than 32 weeks of 32 newborn intensive care units (NICUs) in China between January 1, 2018 and December 31, 2020. EOS was defined by isolation of pathogenic species from blood culture within 72 h of birth. Results: A total of 108 EOS cases (18.4 per 1000 admissions) were identified among 5865 very preterm infants. Incidence of EOS increased with the decrease of GA and birthweight. Escherichia coli(n= 44, 40.7%) was the most common pathogen, followed by Klebsiellaspp. (n= 10, 9.3%). The distribution and proportion of pathogenic bacteria varied significantly by GA. E. coliand Klebsiellaspp. showed high resistance to ampicillin and third-generation cephalosporins, while they showed good susceptibility to carbapenem antibiotics and piperacillin–tazobactam. Conclusion: Our data demonstrated that pathogens causing neonatal EOS showed high rates of resistance to ampicillin and third-generation cephalosporins. This raised questions about the best empirical antibiotic choice for preterm infants suspected of having EOS in low- and middle-income countries (LMICs).
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- 2022
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13. Design and analysis of the mechanical properties of controllable porous scaffolds for bone tissue engineering
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Wang, Xiaokang, Chen, Jigang, Kang, Yongxing, and Sun, Li
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The porous scaffold – a substitute for artificial bone – is vital to bone defect repair and bone tissue regeneration in tissue engineering. In consideration of the limitations of few existing design methods, the significant difference between the internal pore structure of porous scaffolds and natural bone microstructure, and the low controllability of design methods. Based on Voronoi-Tessellation (VT) and random function theory, this paper proposed a design method with controllable pore density, adjustable pore shape and size, and heterogeneous pore distribution. The stress change law of porous scaffolds under compression was analyzed using finite element simulation experiments; the relationship between the porosity and the structural strength of porous scaffolds was obtained. Furthermore, the anisotropy of porous scaffolds was studied, and the change law of the macroscopic equivalent elastic modulus with the change in porosity of porous scaffolds was acquired. Under the same porosity, the mechanical properties of the porous scaffold with a uniform pore distribution and the porous scaffold designed in this paper were analyzed and compared; the damage extension laws of two different porous scaffolds were obtained. The results demonstrate that the design method proposed in this paper has high controllability, and the parametric modeling process is both random and controllable. The internal pore structures of porous scaffolds generated by the design method are closer to the microstructure of natural bone tissue – the structural strength satisfies the requirements of artificial implants.Graphical abstract
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- 2022
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14. Printing dynamic color palettes and layered textures through modeling-guided stacking of electrochromic polymersDedicated to Dr. Seth Marder on the occasion of his 60th birthday.Electronic supplementary information (ESI) available. See DOI: 10.1039/d1mh01098k
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Chen, Ke, Wu, Yukun, You, Liyan, Wu, Wenting, Wang, Xiaokang, Zhang, Di, Elman, James F., Ahmed, Mustafa, Wang, Haiyan, Zhao, Kejie, and Mei, Jianguo
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In printable electrochromic polymer (ECP) displays, a wide color gamut, precise patterning, and controllable color switching are important. However, it is a significant challenge to achieve such features synergistically. Here, we present a solution-processable ECP stacking scheme, where a crosslinker is co-processed with three primary ECPs (ECP-Cyan, ECP-Magenta, and ECP-Yellow), which endows the primary ECPs with solvent-resistant properties and allows them to be sequentially deposited. Viavarying the film thickness of each ECP layer, a full-color palette can be constructed. The ECP stacking strategy is further integrated with photolithography. Delicate multilayer patterns with overhang and undercut textures can be generated, allowing information displays with spatial dimensionality. In addition, viamodulating the stacking sequence, the electrochemical onset potentials of the ECP components can be synchronized to reduce unwanted intermediate colors that are often found in co-processed ECPs. Should specific color properties be desired, COMSOL modeling could be applied to guide the stacking. We believe that this ECP stacking strategy opens a new avenue for electrochromic printing and displays.
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- 2022
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15. CIOD: an intelligent class-incremental object detection system with nearest mean of exemplars
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Ren, Sheng, He, Yan, Wang, Xiaokang, Guo, Kehua, Barra, Silvio, and Li, Jianqi
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Object detection has been widely used in intelligent video surveillance, robot navigation, industrial detection, and other fields. Object detection can effectively reduce the consumption of human capital and has important practical significance. However, the existing object detection methods lack adaptability to the application environment and need to obtain all images classes at one time to train the model in a static setting, and do not support the incremental learning. Therefore, we propose a novel Class-Incremental Object Detection (CIOD) framework based on deep learning. CIOD divides object detection into two stages: object candidate box generation and selection. In the first stage, we improved the traditional OpenCV cascaded classifier to adapt to class-incremental learning while maintaining accuracy. In the second stage, we use example sets and prototype vectors to construct a class increment-based classifier to identify the generated object candidate box. We verify the effectiveness of the proposed method in terms of object detection effect, efficiency, and memory capacity. Experimental results show that CIOD can detect object in a class-incremental manner and can control the memory capacity not to increase with the number of newly increased classes.
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- 2022
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16. Aberrant long non-coding RNA cancer susceptibility 15 (CASC15) plays a diagnostic biomarker and regulates inflammatory reaction in neonatal sepsis
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Song, Jia, Yu, Ruihua, Qi, Jianhong, Wang, Xiaokang, and Shen, Qingqing
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ABSTRACTNeonatal sepsis (NS) is one of the important causes of neonatal death. There are many studies to confirm the role of long non-coding RNA (lncRNA) in neonatal infectious diseases. This study aimed to explore the level of cancer susceptibility 15 (CASC15) and its effect on inflammatory response in NS. Seventy-nine neonatal pneumonia (NP) patients and 80 NS patients were enrolled in this study. Reverse Transcription-quantitative PCR (RT-qPCR) was used to determine the expression levels of CASC15 and miR-144-3p. Receiver operating characteristic (ROC) curve was drawn to evaluate the diagnostic value of CASC15 in NS. RAW264.7 cells were stimulated with LPS to simulate the inflammatory response in NS patients, and the regulation and mechanism of CASC15 on the inflammatory response were explored in this in vitro cell model. Serum CASC15 was upregulated in NS patients, and it had the ability to distinguish NS patients from NP patients. LPS stimulation increased the expression of CASC15 and simultaneously stimulated the secretion of inflammatory cytokines, while the knockdown of CASC15 alleviated the inflammatory response induced by LPS stimulation. Besides, serum miR-144-3p was reduced in NS patients, and luciferase reporter genes showed that miR-144-3p was a direct target of CASC15. Overexpression of CASC15 may promote the inflammatory response of NS by targeted regulating the expression of miR-144-3p, which may provide us with new insights in the treatment of NS.
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- 2021
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17. Risk spillover network structure learning for correlated financial assets: A directed acyclic graph approach.
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Wang, Xiaokang, Wang, Huiwen, Wang, Zhichao, Lu, Shan, and Fan, Ying
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DIRECTED acyclic graphs , *COVID-19 pandemic , *LEAST squares , *ALGORITHMS , *ASSETS (Accounting) - Abstract
Using cross-asset return data in global financial markets, we propose a novel empirical framework to identify the causal structure of the asset risk spillover network. The joint return distribution of the global financial system can be characterized using a directed acyclic graph approach. However, since assets tend to be highly correlated during market turbulence, when adopting a nodewise penalized regression approach for neighborhood estimation, parameter estimates will receive large standard errors, and edges cannot be reliably estimated. In this work, we propose a two-stage approach for directed acyclic graph skeleton estimation for highly correlated variables. In the first stage, a variable screening ensemble is incorporated into the sparse partial least squares regression method to both reduce the size of the active variables set and impose an adaptive penalization on the weight vectors. In the second stage, a modified PC algorithm based on Gram-Schmidt orthogonalization is applied to remove the false positive edges. Simulation studies are conducted to demonstrate the effectiveness of the proposed method. Finally, we apply our method to analyze the asset risk spillover channels for international financial assets during the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]
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- 2021
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18. Advanced oxidation protein products downregulate CYP1A2 and CYP3A4 expression and activity via the NF-κB-mediated signaling pathway in vitro and in vivo
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Xun, Tianrong, Lin, Zhufen, Wang, Xiaokang, Zhan, Xia, Feng, Haixing, Gan, Danna, and Yang, Xixiao
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Uremic toxin accumulation is one possible reason for alterations in hepatic drug metabolism in patients with chronic kidney disease (CKD). However, the types of uremic toxins and underlying mechanisms are poorly understood. In this study, we report the role of advanced oxidation protein products (AOPPs), a modified protein uremic toxin, in the downregulation of cytochromes P450 1A2 (CYP1A2) and P450 3A4 (CYP3A4) expression levels and activities. We found that AOPP accumulation in plasma in a rat CKD model was associated with decreased protein levels of CYP1A2 and CYP3A4. CYP1A2 and CYP3A4 metabolites (acetaminophen and 6β-hydroxytestosterone, respectively,) in liver microsomes were also significantly decreased. In human hepatocytes, AOPPs significantly decreased CYP1A2 and CYP3A4 protein levels in a dose- and time-dependent manner and downregulated their activities; however, bovine serum albumin (BSA), a synthetic precursor of AOPPs, had no effect on these parameters. The effect of AOPPs was associated with upregulation of p-IKKα/β, p-IκBα, p-NF-κB, and inflammatory cytokines protein levels and increases in p-IKKα/β/IKKα, p-IκBα/IκBα, and p-NF-κB/NF-κB phosphorylation ratios. Further, NF-kB pathway inhibitors BAY-117082 and PDTC abolished the downregulatory effects of AOPPs. These findings suggest that AOPPs downregulate CYP1A2 and CYP3A4 expression and activities by increasing inflammatory cytokine production and stimulating NF-κB-mediated signaling. Protein uremic toxins, such as AOPPs, may modify the nonrenal clearance of drugs in patients with CKD by influencing metabolic enzymes.
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- 2021
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19. Asymmetrical Modification of Cyclopentadienyl Cobalt in Eu-MOF for C2H2/CO2Separation
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Wang, Xiaokang, Liu, Hongyan, Sun, Meng, Gao, Fei, Feng, Xueying, Xu, Mingming, Chen, Hui, Yao, Kun, Fan, Weidong, and Sun, Daofeng
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The development of novel adsorption materials is of significance for the efficient and low-energy purification of acetylene (C2H2). Emerging metal–organic framework (MOF) adsorbents demonstrate great application prospects in the field of gas adsorption and separation. Herein, we synthesized a Eu-MOF asymmetrically modified with cyclopentadienyl cobalt exhibiting two different types of cages, denoted as UPC-119. Adsorption isotherms and dynamic breakthrough curves confirm its potential in C2H2/CO2separation, which is further evidenced by theoretical simulations. The high adsorption capacity and low adsorption enthalpy render UPC-119 as a promising adsorbent for C2H2/CO2separation with ease of regeneration.
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- 2024
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20. A Precise Microreactor for Ultralong Visible Chemiluminescence
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Wang, Yutong, Fu, Mingyue, Sun, Meng, Li, Fugang, Gao, Fei, Wang, Xiaokang, Yang, Xinlei, Liu, Hongyan, Xiao, Zhenyu, Fan, Weidong, and Sun, Daofeng
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Chemiluminescence microreactors (CLMR) integrate catalytic centers, luminescent centers, and open channels into an atomic-scale platform, which can provide significantly enhanced light emission compared with usual homogeneous solvent systems. Herein, we report a novel metal–organic framework (MOF), UPC-88, which is constructed by a lophinyl-functionalized H4LIM-2Hligand (4,4′,4″,4‴-((naphthalene-1,4-diylbis(4,1-phenylene))bis(1H-imidazole-2,4,5-triyl))tetrabenzoic acid) with the first double (metal/organic) H2O2catalytic center for CLMR. Due to the fixed chromophore and integrated dual catalytic sites, the relaxation phenomenon is greatly reduced and the energy transfer efficiency is significantly improved, resulting in the outstanding light emission performance of UPC-88. The visible luminous time of the UPC-88 system up to 1100 min was recorded as one of the highest ever reported for MOF systems. We linearly fitted the fluorescence intensity and fluorescence power for the first time, and the results show that UPC-88 is the MOF chemiluminescent material with the highest fluorescence power reported so far. The exploration of the CL reaction mechanism reveals the key role of the lophine base center in the decomposition of hydrogen peroxide, enabling the efficient conversion of chemical energy to light energy. This platform will provide a theoretical and experimental basis for next-generation CLMR systems and improved CL performance.
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- 2024
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21. Absolute pose estimation of UAV based on large-scale satellite image
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WANG, Hanyu, SHEN, Qiang, DENG, Zilong, CAO, Xinyi, and Wang, Xiaokang
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Obtaining absolute pose based on pre-loaded satellite images is one of the important means of autonomous navigation for small Unmanned Aerial Vehicles (UAVs) in Global Navigation Satellite System (GNSS) denied environments. Most of the previous works have tended to build Convolutional Neural Networks (CNNs) to extract features and then directly regress the pose, which will fail when solving the challenges caused by the huge viewpoint and size differences between “UAV-satellite” image pairs in real-world scenarios. Therefore, this paper proposes a probability distribution/regression integrated deep model with the attention-guided triple fusion mechanism, which estimates discrete distributions in pose space and three-dimensional vectors in translation space. In order to overcome the shortage of the relevant dataset, this paper simulates image datasets captured by UAVs with forward-facing cameras during target searching and autonomous attacking. The effectiveness, superiority, and robustness of the proposed method are verified by simulated datasets and flight tests.
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- 2024
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22. Functions, mechanisms, and therapeutic implications of noncoding RNA in acute myeloid leukemia
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Wang, Xiaokang, Tong, Yong, Xun, Tianrong, Feng, Haixing, Lei, Yuhe, Li, Yuanqing, Wu, Kit Hang, and Qiu, Fang
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Acute myeloid leukaemia (AML) is a malignant disease of myeloid hematopoietic stem/progenitor cells. Despite improved understanding of the pathogenesis of AML since the 1980s, the standard treatment for AML has remained virtually unchanged. Numerous studies have found poor survival rates and high relapse rates among older patients with AML. Several novel therapies for AML, including cytotoxic drugs, genetically- and epigenetically-targeted drugs, and immunotherapies, have been developed in recent years. Alternative treatments with improved efficacy are required for AML because many patients cannot tolerate the toxic effects of chemotherapy. Non-coding RNAs, including microRNAs (miRNAs), long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs), are attractive treatment targets for cancers and several other diseases. LncRNAs, miRNAs and circRNAs regulate DNA transcription and translation. Over the past decade, significant efforts have been made to develop RNA-based therapies, mainly antisense oligonucleotides and small interfering RNA, some of which have been approved for clinical use. Here we reviewed the mechanisms underlying the in vitroand in vivoeffects of promising targets and potential drugs, focusing on the drugs most likely to be used for clinical treatment, to aid in the development of precision therapy for AML.
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- 2024
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23. Gut microbiota-derived metabolites as novel therapies for inflammatory bowel diseases: Role of nuclear receptors
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Li, Feng, Wang, Xiaokang, Cai, Yuting, Lin, Yanke, Tang, Ying, and Wang, Shuai
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Inflammatory bowel diseases (IBDs) are increasingly recognized as a pressing global health concern. The gut microbiome emerges as both a potential therapeutic target and a repository for pharmacological interventions in IBDs management. This perspective aims to elucidate the pivotal findings from recent studies concerning the anti-inflammatory properties of gut microbiota-derived metabolites (GMDMs), dissect the strengths and challenges of GMDMs as treatment strategies for IBDs, and highlight the integral role of nuclear receptors in mediating the interplay between IBD pathogenesis and GMDMs. Through the integration of these perspectives, our objective is to deepen the understanding of the therapeutic promise of nuclear receptor-targeted GMDMs, thus propelling forward the exploration and formulation of new pharmacological treatments for IBDs.
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- 2024
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24. A 3D Ba-MOF for selective adsorption of CO2/CH4and CO2/N2
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Wang, Xiaokang, Wang, Yutong, Lu, Kebin, Jiang, Weifeng, and Dai, Fangna
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A Ba-MOF was obtained based on an in-situpartial hydrolysate of ligand and exhibited high separation selectivity for CO2/CH4and CO2/N2at ambient conditions.
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- 2021
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25. Management of Lisfranc injury with anterolateral calcaneal compression fracture
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Gu, Wenqi, Zhang, Rui, Liu, Wanjun, Shi, Zhongmin, Mei, Guohua, Xue, Jianfeng, Zou, Jian, Wang, Xiaokang, Jiang, Jiantao, Yin, Yanjie, and Hao, Xiuyuan
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- 2022
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26. In Situ Measurement of Breathing Strain and Mechanical Degradation in Organic Electrochromic Polymers
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Wang, Xiaokang, de Vasconcelos, Luize Scalco, Chen, Ke, Perera, Kuluni, Mei, Jianguo, and Zhao, Kejie
- Abstract
Organic mixed ionic–electronic conductors (OMIECs) are an emerging family of materials crucial in the development of flexible, bio-, and optoelectronics. In electrochromic polymers, the cyclic redox reaction is associated with a mechanical breathing strain, which deforms the OMIECs and degrades the device reliability. We set forth an in situ nanoindentation approach to measure the breathing strain of a poly(3,4-propylenedioxythiophene) (PProDOT) thin film in a customized liquid cell during electrochromic cycles. A breathing volumetric strain of 12–25% is persistent in different sets of electrolytes of various solvents, salts, and salt molarities. The electrochemical conditioning, intermittence time, and cyclic protocol have minor effects on the mechanical response of PProDOT. The mechanical behavior and anion diffusivity measurement further infer the redox kinetics. Heavily cycled PProDOT films show reduced volumetric strain and accumulated mechanical damage of channel cracks and dysfunctional regions of slow and inhomogeneous electrochromic switching. This work is a systematic characterization of mechanical deformation and damage in a model OMIEC and informs the mechanical reliability of organic electrochromic devices.
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- 2020
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27. A novel CpG-methylation-based nomogram predicts survival in colorectal cancer
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Wang, Xiaokang, Wang, Danwen, Liu, Jinfeng, Feng, Maohui, and Wu, Xiongzhi
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ABSTRACTAberrant DNA methylation is significantly associated with the prognosis of patients with colorectal cancer (CRC). Therefore, the aim of this study was to develop a CpG-methylation-based nomogram for prognostic prediction in CRC. First, 378 CRC patients with methylation data from The Cancer Genome Atlas were randomly divided into training cohort (n = 249) and test cohort (n = 129). A multistep screening strategy was performed to identify six CpG sites that were significantly associated with overall survival in the training cohort. Then, Cox regression modelling was performed to construct a prognostic signature based on the candidate CpG sites. The six-CpG signature successfully separated patients into high-risk and low-risk groups in both training and test cohorts, and its performance was superior to that of previously published methylation markers (P< 0.05). Furthermore, we established a prognostic nomogram incorporating this signature, TNM stage, and age. The nomogram exhibited better prediction for overall survival in comparison with the three independent prognostic factors in the training cohort (C-index: 0.798 vs 0.620 to 0.737; P< 0.001). In the test cohort, the performance of nomogram was also superior to that of the three independent prognostic factors (C-index: 0.715 vs 0.590 to 0.665; P< 0.05). Meanwhile, the calibration curves for survival probability showed good agreement between prediction by nomogram and actual observation in both training and test cohorts. Together, the present study provides a novel CpG-methylation-based nomogram as a promising predictor for overall survival of CRC patients, which may help improve decision-making regarding the personalized treatments of patients with CRC.
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- 2020
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28. Discovery, Design, and Structural Characterization of Alkane-Producing Enzymes across the Ferritin-like Superfamily
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Mak, Wai Shun, Wang, XiaoKang, Arenas, Rigoberto, Cui, Youtian, Bertolani, Steve, Deng, Wen Qiao, Tagkopoulos, Ilias, Wilson, David K., and Siegel, Justin B.
- Abstract
To complement established rational and evolutionary protein design approaches, significant efforts are being made to utilize computational modeling and the diversity of naturally occurring protein sequences. Here, we combine structural biology, genomic mining, and computational modeling to identify structural features critical to aldehyde deformylating oxygenases (ADOs), an enzyme family that has significant implications in synthetic biology and chemoenzymatic synthesis. Through these efforts, we discovered latent ADO-like function across the ferritin-like superfamily in various species of Bacteria and Archaea. We created a machine learning model that uses protein structural features to discriminate ADO-like activity. Computational enzyme design tools were then utilized to introduce ADO-like activity into the small subunit of Escherichia coliclass I ribonucleotide reductase. The integrated approach of genomic mining, structural biology, molecular modeling, and machine learning has the potential to be utilized for rapid discovery and modulation of functions across enzyme families.
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- 2020
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29. A Stable Interpenetrated Zn-MOF with Efficient Light Hydrocarbon Adsorption/Separation Performance
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Wang, Xia, Wang, Xiaokang, Zhang, Xiurong, Fan, Weidong, Li, Qing, Jiang, Weifeng, Dai, Fangna, and Sun, Daofeng
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The design of MOFs with functionalized groups as well as suitable pore space plays a momentous part in gas adsorption and separation. Herein, a new Zn-MOF (Zn4(BTB-NH2)3·xsolvent, UPC-98, H3BTB-NH2= 2′-amino-5′-(4-carboxyphenyl)-[1,1′:3′,1″-terphenyl]-4,4″-dicarboxylic acid) was synthesized successfully by an amino-functionalized ligand (H3BTB-NH2) for light hydrocarbon adsorption and separation application. UPC-98with twofold interpenetrating structure retains relatively high thermal stability and acid–base stability, which can be stable in aqueous solutions (pH = 4–9) and air environment at 250 °C. Interestingly, UPC-98with micropore of 4–5 Å displays a high uptake of C3H8(118.4 cm3·g–1) and C3H6(120.5 cm3·g–1) at 273 K and exhibits excellent adsorption selectivity of C3/C1and C2/C1. The effective separation performance for C2H2/C2H4is confirmed via breakthrough experiments.
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- 2020
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30. A Wide-Deep-Sequence Model-Based Quality Prediction Method in Industrial Process Analysis
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Ren, Lei, Meng, Zihao, Wang, Xiaokang, Lu, Renquan, and Yang, Laurence T.
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Product quality prediction, as an important issue of industrial intelligence, is a typical task of industrial process analysis, in which product quality will be evaluated and improved as feedback for industrial process adjustment. Data-driven methods, with predictive model to analyze various industrial data, have been received considerable attention in recent years. However, to get an accurate prediction, it is an essential issue to extract quality features from industrial data, including several variables generated from supply chain and time-variant machining process. In this article, a data-driven method based on wide-deep-sequence (WDS) model is proposed to provide a reliable quality prediction for industrial process with different types of industrial data. To process industrial data of high redundancy, in this article, data reduction is first conducted on different variables by different techniques. Also, an improved wide-deep (WD) model is proposed to extract quality features from key time-invariant variables. Meanwhile, an long short-term memory (LSTM)-based sequence model is presented for exploring quality information from time-domain features. Under the joint training strategy, these models will be combined and optimized by a designed penalty mechanism for unreliable predictions, especially on reduction of defective products. Finally, experiments on a real-world manufacturing process data set are carried out to present the effectiveness of the proposed method in product quality prediction.
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- 2020
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31. Silica-Modified Ordered Mesoporous Carbon for Optimized Impedance-Matching Characteristic Enabling Lightweight and Effective Microwave Absorbers
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Zhou, Panpan, Zhang, Jing, Zhu, Hongli, Wang, Lixi, Wang, Xiaokang, Song, Zhi, Zhang, Qitu, Yu, Mingxun, Liu, Zhihao, Xu, Tong, Feng, Wanxun, and Feng, Xia
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Ordered mesoporous carbon (OMC) is considered to be a prospective carbon-based material for microwave absorption because of its abundant well-ordered mesoporous structures, high specific surface area, numerous active sites, and facile preparation process. However, its development has been seriously hindered by its poor impedance-matching characteristic. Herein, silica-modified OMC composites with a designable impedance-matching transition layer are successfully fabricated via a self-assembly method and succeeding calcination treatment. In addition, the silica in OMC@SiO2composites can maintain the mesoporous structure, which facilitates the scattering and reflection of microwaves in the tunnel structure. The as-prepared sample OMC-5@SiO2exhibits a minimum reflection loss (RL) value of −40.7 dB at 10.8 GHz with 2 mm and an effective absorption bandwidth (RL ≤ −10 dB) of 4.8 GHz with a thinner absorber thickness of 1.5 mm. We believe that the as-prepared OMC@SiO2composites can be prospective candidates as high-efficiency and lightweight microwave absorbers.
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- 2020
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32. A Distributed Tensor-Train Decomposition Method for Cyber-Physical-Social Services
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Wang, Xiaokang, Yang, Laurence T., Wang, Yihao, Liu, Xingang, Zhang, Qingxia, and Deen, M. Jamal
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- 2019
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33. Two alkynyl functionalized Co(II)-MOFs as fluorescent sensors exhibiting selectivity and sensitivity for Fe3+and nitroaromatic compounds
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Li, Yue, Wang, Xia, Xing, Chengyong, Zhang, Xiurong, Liang, Zelong, Wang, Xiaokang, Zhang, Kai, Wang, Yutong, Liu, Di, Fan, Weidong, and Dai, Fangna
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Two alkynyl functionalized 3D frameworks for selective and sensitive detection of Fe3+ions and nitroaromatic compounds through fluorescence quenching.
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- 2019
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34. Topology Exploration in Highly Connected Rare-Earth Metal–Organic Frameworks via Continuous Hindrance Control
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Wang, Yutong, Feng, Liang, Fan, Weidong, Wang, Kun-Yu, Wang, Xia, Wang, Xiaokang, Zhang, Kai, Zhang, Xiurong, Dai, Fangna, Sun, Daofeng, and Zhou, Hong-Cai
- Abstract
The structural diversity of highly connected metal–organic frameworks (MOFs) has long been limited due to the scarcity of highly connected metal clusters and the corresponding available topology. Herein, we deliberately chose a series of tritopic linkers with multiple substituents to construct a series of highly connected rare-earth (RE) MOFs. The steric hindrance of these substituents can be systematically tuned to generate various linker rotamers with tunable configurations and symmetries. For example, the methyl-functionalized linker (L-CH3) with C2vsymmetry exhibits larger steric hindrance, forcing two peripheral phenyl rings perpendicular to the central one. The combination of C2vlinkers and 9-connected RE6clusters leads to the formation of a new fascinating (3,9)-c septopology. Unlike Zr-MOFs exhibiting Zr6clusters in various linker configurations and corresponding different structures, the adaptable RE6clusters can undergo metal insertion and rearrange into new RE9clusters when connected to an unfunctionalized linker (L–H) with C1symmetry, giving rise to a new (3,3,18)-c ytwtopology. More interestingly, by judiciously combining the linkers with both small and bulky substituents through mixed-linker strategies, an RE9-based MOF with an engaging (3,3,12)-c flgtopology could be obtained as a result of continuous steric hindrance control. In this case, the two mixed linkers adopt configurations with moderate steric hindrances. Molecular simulation demonstrates that the combination of substituents with various steric hindrances dictates the resulting MOF structures. This work provides insights into the discovery of unprecedented topologies through systematic and continuous steric tuning, which can further serve as a blueprint for the design and construction of highly complicated porous structures for sophisticated applications.
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- 2019
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35. Effect of Functional Groups on the Adsorption of Light Hydrocarbons in fmj-type Metal–Organic Frameworks
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Wang, Yutong, Wang, Xia, Wang, Xiaokang, Zhang, Xiurong, Fan, Weidong, Liu, Di, Zhang, Liangliang, Dai, Fangna, and Sun, Daofeng
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The functionalized modification of targeted porous metal–organic frameworks (MOFs) is important to improve the adsorption capacity of light hydrocarbon gases. Five isomorphic MOFs with different functional groups (F, Cl, NH2, CH3, and OCH3) are successfully synthesized by systematic functional modification of UMCM-151. By studying the adsorption properties of C2and C3hydrocarbons (C2H2, C2H4, C2H6, C3H6, and C3H8), it is found that the electron-withdrawing group functional UMCM-151-Fand UMCM-151-Clexhibit strong affinity for C2H2(98.71 cm3g–1for UMCM-151-Fand 90.29 cm3g–1for UMCM-151-Cl), while the electron-donating group functional UMCM-151-NH2, UMCM-151-CH3, and UMCM-151-OCH3have strong affinity for C2H4(97.89 cm3g–1for UMCM-151-NH2, 90.22 cm3g–1for UMCM-151-CH3and 94.13 cm3g–1for UMCM-151-OCH3). The differences in affinity of electron effects for light hydrocarbon provide an experimental basis for porous MOFs to improve their light hydrocarbon storage capacity.
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- 2019
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36. EEG control variable algorithm and motion control strategy for toy rail car
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Pan, Hongguang, Wang, Mei, Wang, Xiaokang, and Lin, Jzau-Sheng
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For training the thought concentration ability of hyperactivity sufferers, this paper proposed a kind of electroencephalogram (EEG) control variable extraction method and the motion control strategy. Firstly, the technologies of EEG acquisition from frontal lobe, and the wireless data transmission from the acquisition card to the Pad Phone were realised. Then, through the wavelet Mallat algorithm and FFT to extract the EEG control variable, the accurate controls of start, stop, and running velocity of the toy rail car were implemented. Thirdly, the mathematical model between the velocity and the EEG control variable was established, and then the start threshold, the swerve control and the speed adjust method were accurately designed using this model, so that the delay start and the swerve speed were solved. In addition, the wireless data transmissions among the Pad Phone, the EEG acquisition module and the railelectric potential controller were realised. Finally, it was proved that the proposed EEG control variables and the control strategy effectively fulfil the accurate speed control and the stable motion control.
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- 2019
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37. Tunable and functional phosphonium-based deep eutectic solvents for synthesizing of cyclic carbonates from CO2and epoxides under mild conditions
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Cui, Yuanyuan, Wang, Xiaokang, Dong, Li, Liu, Yifan, Chen, Songsong, Zhang, Junping, and Zhang, Xiangping
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Carbon dioxide (CO2) conversion into carbonates is one of the important ways to reduce carbon emissions. In this study, several phosphonium-based functional deep eutectic solvents (DESs) were prepared as catalysts for the synthesis of cyclic carbonates under mild conditions. The research showed that under mild conditions (60 °C, 0.8 MPa, 4 h, and 3.5 mol% catalyst loading), 1-ethylamine-3-butylphosphine bromide−diethylene glycol ([P4,4,4,2NH2][Br]-DEG) DES catalyst can achieve 96% propylene carbonate (PC) yield. In addition, the DES catalyst can be recovered by simple solvent extraction, and the PC yield does not decrease significantly after five cycles. Finally, in situ FT-IR and density functional theory (DFT) were used to provide a potential reaction mechanism for the cycloaddition reaction. Mechanism studies show that synergistic catalysis between quaternary phosphine ionic liquids (ILs) and ethylene glycol (EG)/DEG promotes CO2conversion to cyclic carbonate.
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- 2023
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38. Impact of Thermally Forced Circulations on the Diurnal Cycle of Summer Precipitation Over the Southeastern Tibetan Plateau
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Wang, Jingyu, Yuan, Huiling, Wang, Xiaokang, Cui, Chunguang, and Wang, Xiaofang
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The summer precipitation over the southeastern Tibetan Plateau (SETP) exhibits significant diurnal variability, with a notable peak before midnight. This study investigates how thermally forced circulations regulate the diurnal precipitation over the SETP, using surface rain‐gauge observations and high‐resolution reanalysis data from June to August during 2015–2019. Water vapor supply and precipitation onset in the afternoon are associated with the upslope winds and upward motions of the mountain–plains solenoid (MPS) between the SETP and nearby lowlands (the Sichuan Basin and Yunnan–Guizhou Plateau). After sunset, the sustained easterly and stronger southerly winds below 500 hPa transport abundant moisture from the rainy lowlands to the SETP. The findings suggest that these winds are mainly due to the larger zonal continental‐scale thermally forced circulation combined with the meridional large‐scale MPS before midnight and the meridional small‐scale MPS after midnight. The summer rainfall over the southeastern Tibetan Plateau (SETP) is crucial to the hydrological cycle of both the SETP and nearby regions. However, it remains unclear why the rainfall over the SETP mostly occurs at night due to limited observations. This study aims to investigate the role of thermally driven winds in diurnal rainfall during summer (June–August) over the SETP, using high‐resolution reanalysis data and surface rain‐gauge observations. The results show that the strong upward motions and low‐level upslope winds of the thermally forced mountain‐valley wind systems (MVWS) between the SETP and the lowlands (Sichuan Basin and Yunnan–Guizhou Plateau) help to trigger the precipitation and transport moisture in the afternoon. After sunset, thermally forced circulations, including the east–west continental‐scale thermal circulation between the Asian continent and its adjacent ocean, the north–south large‐scale MVWS between the Yunnan–Guizhou Plateau and its southern plain, and the north–south small‐scale MVWS between the SETP and its southern slope, help maintain horizontal winds from the rainy lowlands, transporting abundant moisture to facilitate the rainfall over the SETP at night. Thermally forced circulations greatly impact the diurnal cycle of summer precipitation over the southeastern Tibetan Plateau (SETP)Daytime rainfall over this region is associated with the upward motions and upslope winds of the mountain–plains solenoidMulti‐scale thermal circulations are responsible for moisture transport of nighttime rainfall over the SETP Thermally forced circulations greatly impact the diurnal cycle of summer precipitation over the southeastern Tibetan Plateau (SETP) Daytime rainfall over this region is associated with the upward motions and upslope winds of the mountain–plains solenoid Multi‐scale thermal circulations are responsible for moisture transport of nighttime rainfall over the SETP
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- 2023
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39. A continuum theory of organic mixed ionic-electronic conductors of phase separation.
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Wang, Xiaokang and Zhao, Kejie
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PHASE separation , *FINITE model theory , *FINITE element method , *ELECTROSTATIC fields , *THERMODYNAMIC laws , *CONSERVATION of mass - Abstract
Organic mixed ionic-electronic conductors (OMIECs) are the core functioning component in the emerging flexible, bio-, and optoelectronics owning to their unique capability of mixed conduction. Of all types, two-phase OMIECs exhibit exceptional performance due to their high stretchability and balanced ionic-electronic conduction. However, the electron-conducting phase may segregate from the ion-conducting phase in a two-phase OMIEC, changing the conducting path and eventually leading to degraded performance and dysfunction of the devices. In this work, we formulate a continuum theory following the thermodynamics framework of a two-phase OMIEC undergoing phase separation. The free energy consists of contributions from the deformation of the polymer chains, the mixing of the polymer with salts and solvents, the electrostatic field, and the two-phase interfaces. The equilibrium conditions and kinetics equations are derived with the constraint of mass conservation, thermodynamics laws, and electrostatics. We implement the theory into a finite element model and study the mechanics and electrochemistry of the OMIEC channel in an electrolyte-gated organic electrochemical transistor (OECT) device. The computational model captures the concurrent transport of charge carriers, mechanical swelling, and phase separation in the OMIEC and replicates the transfer curves of an OECT which agree well with the experiments. More specifically, we reveal the origin of the volumetric capacitance as the accumulation of charge carriers at the two-phase interfaces. We examine the parametric space to elucidate experimental observations such as molecular size-dependent conductivity and substrate-dependent phase separation. The swelling behavior and the transfer curves of OECTs under stretched, free, and constrained states are compared, demonstrating the effects of deformation on the phase dynamics and the electron-conducting behavior. We show that, for volumetric swelling and the electrochemical transfer curves, the effect of stress-transport coupling dominates while the effect of the Maxwell stress is negligible. This work provides a theoretical basis for the mechanics and electrochemistry of two-phase OMIECs. [ABSTRACT FROM AUTHOR]
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- 2023
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40. Metal-ion-tuned metal-organic frameworks for C2H2/CO2separation
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Sun, Meng, Liu, Hongyan, Wang, Xiaokang, Yang, Xinlei, Gao, Fei, Xie, Deyu, Fan, Weidong, Han, Yinfeng, Xu, Ben, and Sun, Daofeng
- Abstract
Adsorptive separation of acetylene (C2H2) from carbon dioxide (CO2) by adsorption is a viable method for producing high-purity C2H2required for industrial applications. However, separating C2H2and CO2is challenging due to their extremely similar molecular sizes and physical properties. Metal-Organic Frameworks (MOFs), as a novel porous material with high specific surface area and tunable pore size, have shown great potential in the separation and purification of light hydrocarbons. Herein, we synthesized three isoreticular Al-MOFs (Al-TCPP, Al-TCPP(Co), and Al-TCPP(Fe)) by modulating metal ions at the porphyrin center, all of which can effectively separate C2H2/CO2. The addition of metal ions can regulate and improve the separation selectivity of C2H2/CO2. Compared with the parent Al-TCPP, the IAST selectivities of Al-TCPP(Co) and Al-TCPP(Fe) for equimolar C2H2/CO2increased from 1.73 to 3.66 and 4.43, respectively. Breakthrough experiments validate their efficient separation of C2H2/CO2. Furthermore, they all exhibit excellent hydrothermal stability, laying the foundation for practical applications.
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- 2023
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41. Fe-MOF with U-Shaped Channels for C2H2/CO2and C2H2/C2H4Separation
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Li, Yue, Wang, Xiaokang, Yang, Xinlei, Liu, Hongyan, Chai, Xianyi, Wang, Yutong, Fan, Weidong, and Sun, Daofeng
- Abstract
The development of high-performance adsorbents is critical for the low-energy separation of acetylene. Herein, we synthesized an Fe-MOF (MOF, metal–organic framework) with U-shaped channels. The adsorption isotherms of C2H2, C2H4, and CO2show that the adsorption capacity of acetylene is significantly larger than that of the other two gases. Meanwhile, the actual separation performance was verified by breakthrough experiments, indicating the potential to separate C2H2/CO2and C2H2/C2H4mixtures at normal temperatures. Grand Canonical Monte Carlo (GCMC) simulation demonstrates that the framework with U-shaped channels interacts more strongly with C2H2than with C2H4and CO2. The high C2H2uptake and low adsorption enthalpy highlight Fe-MOF as a promising candidate for C2H2/CO2separation with a low regeneration energy.
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- 2023
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42. Absorption Coefficient and Optical Contrast Modulation through Side Chain Engineering of Electrochromic Polymers
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Perera, Kuluni, Wu, Wenting, You, Liyan, Elman, James F., Wang, Zhiyang, Wang, Xiaokang, Ahmed, Mustafa, Ke, Zhifan, and Mei, Jianguo
- Abstract
Conjugated polymers can be electrochemically bleached to achieve colored-to-transmissive electrochromic switching. This work presents a side chain engineering approach to enhance colored state absorptivity of an electrochromic polymer, while maintaining high transmissivity in the bleached state. A series of dioxythiophene copolymers with systematic variations in their branched alkyl side chains have been used to understand side chain influence on solubility, aggregation, film morphology and optical constants. By increasing the chromophore density through an appropriate choice of side chains, the absorption coefficient of the colored polymer can be improved by almost 50%, with minimal influence on bleached-state absorption coefficients over the visible region. As such, solution-processed films of high absorbance can be prepared using thin polymer layers to achieve fast electrochromic switching and highly transmissive bleached states. Under optimized conditions, optical contrasts nearing 80% can be reached at the wavelength of maximum absorbance, among the highest reported for solution-processed, cathodically coloring electrochromic polymers. The improved absorption coefficients are especially useful in enhancing the electrochromic performance in the low transmittance regime (colored state transmittance <20%), providing useful insights for designing high contrast electrochromic materials.
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- 2023
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43. Power user portrait recognition based on feature vector
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Loskot, Pavel, Wang, Ning, Wang, Bo, and Wang, Xiaokang
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- 2022
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44. Doping kinetics in organic mixed ionic–electronic conductors: Moving front experiments and the stress effect
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Wang, Xiaokang, Li, Xuefei, Mei, Jianguo, and Zhao, Kejie
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Organic mixed ionic–electronic conductors (OMIECs) are the core functional component of various organic electrochemical devices. To be highly conductive, OMIECs require electrochemical doping by electron/hole extraction and charge compensation by counter ions, which often induces concomitant changes in material properties for their electrical, optical, and mechanical behaviors. Here, we characterize the doping kinetics of a model solid-state poly(3,4-propylene dioxythiophene) (PProDOT) thin film via a designed moving front experiment using optical microscopy and in-situ nanoindentation. The in-plane front propagation displacement shows bilinear dependence on the square root of time, indicating a diffusion-controlled process. Nanoindentation results show drastic changes in the film morphology and the elastic modulus and hardness upon doping. As the swelling-induced stress may bias the doping kinetics, we observe that an applied pressure as low as 2.8 MPa significantly retards the electrochemical redox reaction. Theoretical modeling is proposed and implemented using the finite element method, which well captures the doping kinetics of PProDOT under stress. We also evaluate the diffusivity dependence on the doping level and the mechanical stress. This work sheds light on the coupled electrochemical and mechanical responses of OMIECs.
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- 2022
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45. Evaluation of the biocompatibility of a hydroxyapatite-CaTiO3coating in vivo
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Wu, Song, Tu, Bing, Lin, Jianghong, Wang, Zili, Wang, Xiaokang, Shen, Minren, and Hu, Rong
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This study was designed to evaluate the biocompatibility and osteointegrative activity of hydroxyapatite (HA)-CaTiO3, titanium substrate, traditional HA coating and CaTiO3coating via an animal experiment.
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- 2015
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46. Intensity-modulated radiotherapy with more than 60 Gy improved the survival of inoperable patients with locally advanced esophageal squamous cell carcinoma
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Zhang, Wei, Xie, Qing, Zhu, Bifa, Wang, Xiaokang, He, Ling, Zhang, Yong, and Cruz., Jorddy Neves
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- 2022
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47. Z-number dominance, support and opposition relations for multi-criteria decision-making.
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Peng, Honggang, Xiao, Zhi, Wang, Xiaokang, Wang, Jianqiang, and Li, Jian
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MULTIPLE criteria decision making , *DECISION making , *SOCIAL dominance , *DISTILLATION - Abstract
The outranking multi-criteria decision-making (MCDM) method focuses on the systematic comparison of alternatives and the non-compensation among criteria to conduct decision analysis. Z-numbers are powerful tools for characterizing decision-making information and identifying information reliability. This paper aims to explore Z-number outranking theories and the corresponding MCDM method on the basis of the idea of Elimination and Choice Translating Reality (ELECTRE) III, which is a very popular and capable outranking model. The concordance and discordance indices of Z-numbers are defined by processing their bimodal uncertainty fully. And an objective computation method is investigated to determine the values of thresholds in these indices. Further, three types of novel outranking relations, including dominance, support and opposition relations, for Z-numbers are presented by comparing these indices systematically. Then, an extended MCDM method with the distillation and flow ranking rules is proposed by detecting the outranking relations among alternatives under multiple criteria and carrying out the outranking aggregation and exploitation. To verify the applicability and effectivity of the proposed method, an illustrative example is provided, and a simulation test and a comparison discussion are conducted [ABSTRACT FROM AUTHOR]
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- 2023
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48. Circularly Recyclable Polymers Featuring Topochemically Weakened Carbon–Carbon Bonds
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Luo, Xuyi, Wei, Zitang, Seo, Bumjoon, Hu, Qixuan, Wang, Xiaokang, Romo, Joseph A., Jain, Mayank, Cakmak, Mukerrem, Boudouris, Bryan W., Zhao, Kejie, Mei, Jianguo, Savoie, Brett M., and Dou, Letian
- Abstract
Closed-loop circular utilization of plastics is of manifold significance, yet energy-intensive and poorly selective scission of the ubiquitous carbon–carbon (C–C) bonds in contemporary commercial polymers pose tremendous challenges to envisioned recycling and upcycling scenarios. Here, we demonstrate a topochemical approach for creating elongated C–C bonds with a bond length of 1.57∼1.63 Å between repeating units in the solid state with decreased bond dissociation energies. Elongated bonds were introduced between the repeating units of 12 distinct polymers from three classes. In all cases, the materials exhibit rapid depolymerization via breakage of the elongated bond within a desirable temperature range (140∼260 °C) while otherwise remaining remarkably stable under harsh conditions. Furthermore, the topochemically prepared polymers are processable and 3D-printable while maintaining a high depolymerization yield and tunable mechanical properties. These results suggest that the crystalline polymers synthesized from simple photochemistry and without expensive catalysts are promising for practical applications with complete materials’ circularity.
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- 2022
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49. A comparative study between graphene oxide and diamond nanoparticles as water-based lubricating additives
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Liu, YuHong, Wang, XiaoKang, Pan, GuoShun, and Luo, JianBin
- Abstract
The tribological properties of graphene oxide (GO) nanosheets and modified diamond (MD) nanoparticles with excellent water-solubility were investigated. GO nanosheets were synthesized using carbon fibers with a regular and uniform size, the lateral size being around 30 nm and the thickness being 2 or 3 nm, while MD nanoparticles were about 30 nm in the three dimensions. The friction properties of ceramics were improved by GO nanosheets or MD nanoparticles used as additives in water-based lubrication, though the effects of two nanoparticles were quite different. For GO nanosheets, the friction coefficient at the beginning decreased sharply from 0.6 to 0.1, as compared with the dionized water lubrication. At the same time, the running-in period was shortened from 2000 s to 250 s. A steady state characterized by ultralow friction (friction coefficient=0.01) was obtained after the running-in period. In the case of MD nanoparticles, the friction coefficient stayed at 0.1 without further decrease during the whole experiment. Based on the observation of wear scar and characterization of remains on the wear track, the positive effect of GO nanosheets was attributed to their lamellar structure and geometric size. MD nanoparticles reduced friction by forming the regularly grained surface on the mating surfaces, and prevented further reduction in steady-state friction coefficient owing to their larger size and hardness. In conclusion, GO nanosheets exhibited favorable potential as an effective additive for water-based lubrication.The tribological properties of graphene oxide (GO) nanosheets and modified diamond (MD) nanoparticles with excellent water-solubility were investigated. GO nanosheets were synthesized using carbon fibers with a regular and uniform size, the lateral size being around 30 nm and the thickness being 2 or 3 nm, while MD nanoparticles were about 30 nm in the three dimensions. The friction properties of ceramics were improved by GO nanosheets or MD nanoparticles used as additives in water-based lubrication, though the effects of two nanoparticles were quite different. For GO nanosheets, the friction coefficient at the beginning decreased sharply from 0.6 to 0.1, as compared with the dionized water lubrication. At the same time, the running-in period was shortened from 2000 s to 250 s. A steady state characterized by ultralow friction (friction coefficient=0.01) was obtained after the running-in period. In the case of MD nanoparticles, the friction coefficient stayed at 0.1 without further decrease during the whole experiment. Based on the observation of wear scar and characterization of remains on the wear track, the positive effect of GO nanosheets was attributed to their lamellar structure and geometric size. MD nanoparticles reduced friction by forming the regularly grained surface on the mating surfaces, and prevented further reduction in steady-state friction coefficient owing to their larger size and hardness. In conclusion, GO nanosheets exhibited favorable potential as an effective additive for water-based lubrication.
- Published
- 2013
- Full Text
- View/download PDF
50. Modification on the tribological properties of ceramics lubricated by water using fullerenol as a lubricating additive
- Author
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Liu, YuHong, Wang, XiaoKang, Liu, PengXiao, Zheng, JunPeng, Shu, ChunYing, Pan, GuoShun, and Luo, JianBin
- Abstract
Abstract: It is necessary to modify the running-in process for the application of ceramics using water as a lubricant in real conditions because ceramics sliding in water are characterized by a running-in period with severe friction and wear. Fullerenol, a kind of highly water-soluble nanoparticle, was synthesized and then used to ameliorate the tribological properties of Si
3 N4 sliding against Al2 O3 in pure water. With the addition of fullerenol, the running-in period was shortened from 30 min to 100 s at a speed of 250 mm/s. The speed threshold above which ultralow friction can be obtained in a short time was expanded from 450 mm/s to 80 mm/s. Meanwhile, the load-carrying ability of water film was increased. The role of fullerenol was discussed based on observation of the wear scar by an optical interferometer and XPS characterization of the tribo-film on the wear track.- Published
- 2012
- Full Text
- View/download PDF
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