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Catalyst-free and Reprocessable Aromatic Polydithiourethanes

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Chinese Journal of Polymer Science 2024年第10期42卷 1435-1441,I0007页

作者： Bo Yang Hai-Jun feng tian-tian Ni Xiao-Rui Zhou Tao Xie Ning zheng State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou310058China Department of Colorectal Surgery and Oncology Key Laboratory of Cancer Prevention and InterventionMinistry of EducationThe Second Affiliated HospitalZhejiang University School of MedicineHangzhou310009China

The incorporation of dynamic covalent bonds into thermosets facilitates the reprocessing of polymer networks,thereby meeting the sustainable requirements for polymer ***,the mechanical properties of many materials often decline significantly upon reprocessing due to side reactions caused by harsh processing *** this work,we find that the aromatic dithiocarbamate bond can undergo dissociation under mild conditions without the need for a catalyst,enabling the efficient reprocessing of the corresponding *** a consequence,the mechanical properties of the polydithiourethane can be largely preserved after *** discovery of this dynamic chemistry is anticipated to broaden the potential for material design in dynamic covalent polymer networks.

关键词： Reprocessing Polydithiourethane Dynamic covalent bond

Exploiting sound for emerging applications of extracellular vesicles

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Nano Research 2024年第2期17卷 462-475页

作者： Zhuhao Wu Hongwei Cai Chunhui tian zheng Ao Lei Jiang feng Guo Department of Intelligent Systems Engineering Indiana UniversityBloomingtonIN 47405USA

Extracellular vesicles are nano-to micro-scale,membrane-bound particles released by cells into extracellular space,and act as carriers of biomarkers and therapeutics,holding promising potential in translational ***,the challenges remain in handling and detecting extracellular vesicles for disease diagnosis as well as exploring their therapeutic capability for disease ***,we review the recent engineering and technology advances by leveraging the power of sound waves to address the challenges in diagnostic and therapeutic applications of extracellular vesicles and biomimetic *** first introduce the fundamental principles of sound waves for understanding different acoustic-assisted extracellular vesicle *** discuss the acoustic-assisted diagnostic methods including the purification,manipulation,biosensing,and bioimaging of extracellular ***,we summarize the recent advances in acoustically enhanced therapeutics using extracellular vesicles and biomimetic ***,we provide perspectives into current challenges and future clinical applications of the promising extracellular vesicles and biomimetic nanovesicles powered by sound.

关键词： extracellular vesicles exosomes biomimetic nanovesicles acoustics disease diagnostics therapeutics

Unveiling the Re,Cr,and I diffusion in saturated compacted bentonite using machine-learning methods

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Nuclear Science and Techniques 2024年第6期35卷 65-77页

作者： zheng-Ye feng Jun-Lei tian Tao Wu Guo-Jun Wei Zhi-Long Li Xiao-Qiong Shi Yong-Jia Wang Qing-feng Li Department of Engineering Huzhou UniversityHuzhou 313000China Institute of Theoretical Physics Shanxi UniversityTaiyuan 030006China College of Physics Science and Technology Shenyang Normal UniversityShenyang 110034China

The safety assessment of high-level radioactive waste repositories requires a high predictive accuracy for radionuclide diffusion and a comprehensive understanding of the diffusion *** this study,a through-diffusion method and six machine-learning methods were employed to investigate the diffusion of ReO_(4)^(−),HCrO_(4)^(−),and I−in saturated compacted bentonite under different salinities and compacted dry *** machine-learning models were trained using two *** dataset contained six input features and 293 instances obtained from the diffusion database system of the Japan Atomic Energy Agency(JAEA-DDB)and 15 *** other dataset,comprising 15,000 pseudo-instances,was produced using a multi-porosity model and contained eight input *** results indicate that the former dataset yielded a higher predictive accuracy than the *** gradient-boosting exhibited a higher prediction accuracy(R2=0.92)and lower error(MSE=0.01)than the other machine-learning *** addition,Shapley Additive Explanations,Feature Importance,and Partial Dependence Plot analysis results indicate that the rock capacity factor and compacted dry density had the two most significant effects on predicting the effective diffusion coefficient,thereby offering valuable insights.

关键词： Machine learning Effective diffusion coefficient Through-diffusion experiment Multi-porosity model Global analysis

Heterogeneous integration of 2D materials on Si charge-coupled devices as optical memory

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Science China(Information Sciences) 2024年第6期67卷 190-197页

作者： zheng BIAN feng tian Zongwen LI Xiangwei SU tianjiao ZHANG Jialei MIAO Bin YU Yang XU Yuda ZHAO College of Integrated Circuits Hangzhou Global Scientific and Technological Innovation CentreZhejiang University

Optical memory integrates the function of optical sensing in memory devices, remarkably promoting the interconnection between sensory and memory terminals. Silicon charge-coupled photodetectors and floating gate memory have been widely used in imaging and storage technologies, respectively. However,the heterogeneous integration of the two devices requires technological innovation and complex electrical connections. In this work, we adopt a three-dimensional layer stacking method to design a novel optical memory device. On the top of Si charge-coupled photodetectors, we successively deposit two-dimensional graphene,hexagonal boron nitride, and molybdenum disulfide as a floating gate layer, a tunneling layer, and a readout layer, respectively. By applying a gate bias on lightly doped Si, a deep depletion layer is formed with a high voltage potential drop. Under dark conditions, the depletion layer cannot be filled, and the electric field across the h-BN tunnel barrier is relatively small. Under light irradiation, the deep depletion layer is gradually filled, and the h-BN tunneling layer withstands the increasing electric field, resulting in charge storage in the floating gate layer. Based on this mechanism, the device exhibits a gate voltage-dependent operation mode, including an integrated optical sensing-memory mode and an electrically driven storage mode. Under moderate gate voltage, the device can effectively detect the optical information with varied intensity and store the optical information in the floating gate, displaying optically controlled memory characteristics. Our work demonstrates a compact device structure for optical memory and displays excellent optically controlled memory performance, which can be applied in artificial vision systems.

关键词： heterogeneous integration charge-coupled device floating gate optical memory molybdenum disulfide lightly doped silicon

Microstructure and Mechanical Behavior of Mg-Based Bimetal Plates with High Formability Sleeve by Co-extrusion

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 499-512页

作者： Yue-Hui Dang Sheng-Lin Liu Xiao-Lei Ai Xiao-Wei feng Bo feng Zhuo tian Ying-Fei Lin Huan-Tao Chen Kai-Hong zheng School of Materials Science and Engineering Chang’an UniversityShaanxi 710064China Guangdong Key Laboratory of Metal Toughening Technology and Application Institute of New MaterialsGuangdong Academy of SciencesGuangzhou 510650China

In this study,microstructure and mechanical behavior of two types of Mg-based bimetal plates with a high formability sleeve were systematically studied,with a great emphasis on the effect of the interface characteristic and the sleeve fraction on the plasticity of composite *** rule of mixtures(ROM)for elongation was also *** results show that when there is no or thin diffusion layer with thickness of about 3μm,Mg-based bimetal plates have a good plasticity with elongation of about 19-24%,and the ROM predicted elongations are very close to the experimental *** contrast,with a diffusion layer about 95-155μm thick,Mg-based bimetal plates exhibit a poor plasticity with elongation of about 11-17%,and the experimental elongations largely deviate from the ROM *** plasticity of Mg-based bimetal plates increases with increasing sleeve *** study provides new insights on the plastic deformation of Mg-based bimetal composites with a high formability sleeve.

关键词： Mg-based composites Co-extrusion Microstructure Mechanical behavior Plastic deformation

Analyzing topics in social media for improving digital twinning based product development

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Digital Communications and Networks 2024年第2期10卷 273-281页

作者： Wenyi Tang Ling tian Xu zheng Ke Yan School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China

Digital twinning enables manufacturers to create digital representations of physical entities,thus implementing virtual simulations for product *** efforts of digital twinning neglect the decisive consumer feedback in product development stages,failing to cover the gap between physical and digital *** work mines real-world consumer feedbacks through social media topics,which is significant to product *** specifically analyze the prevalent time of a product topic,giving an insight into both consumer attention and the widely-discussed time of a *** primary body of current studies regards the prevalent time prediction as an accompanying task or assumes the existence of a preset ***,these proposed solutions are either biased in focused objectives and underlying patterns or weak in the capability of generalization towards diverse *** this end,this work combines deep learning and survival analysis to predict the prevalent time of *** propose a specialized deep survival model which consists of two *** first module enriches input covariates by incorporating latent features of the time-varying text,and the second module fully captures the temporal pattern of a rumor by a recurrent network ***,a specific loss function different from regular survival models is proposed to achieve a more reasonable *** experiments on real-world datasets demonstrate that our model significantly outperforms the state-of-the-art methods.

关键词： Digital twinning Product development Topic analysis Social media

A Trust Evaluation Mechanism Based on Autoencoder Clustering Algorithm for Edge Device Access of IoT

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Computers, Materials & Continua 2024年第2期78卷 1881-1895页

作者： Xiao feng zheng Yuan Cyber Security Academy Beijing University of Posts and TelecommunicationsBeijing100876China Department of Cyberspace Security Beijing Electronic Science and Technology InstituteBeijing100070China State Grid Info-Telecom Great Power Science and Technology Co. Ltd.Beijing102211China

First,we propose a cross-domain authentication architecture based on trust evaluation mechanism,including registration,certificate issuance,and cross-domain authentication processes.A direct trust evaluation mechanism based on the time decay factor is proposed,taking into account the influence of historical interaction *** weight the time attenuation factor to each historical interaction record for updating and got the new historical record *** refer to the beta distribution to enhance the flexibility and adaptability of the direct trust assessment model to better capture time trends in the historical *** we propose an autoencoder-based trust clustering *** perform feature extraction based on *** leibler(KL)divergence is used to calculate the reconstruction *** constructing a convolutional autoencoder,we introduce convolutional neural networks to improve training efficiency and introduce sparse constraints into the hidden layer of the *** sparse penalty term in the loss function measures the difference through the KL *** clustering is performed based on the density based spatial clustering of applications with noise(DBSCAN)clustering *** the clustering process,edge nodes have a variety of trustworthy attribute *** assign different attribute weights according to the relative importance of each attribute in the clustering process,and a larger weight means that the attribute occupies a greater weight in the calculation of ***,we introduced adaptive weights to calculate comprehensive trust *** experiments prove that our trust evaluation mechanism has excellent reliability and accuracy.

关键词： Cross-domain authentication trust evaluation autoencoder

Hydrophobic long-chain two-dimensional perovskite scintillators for underwater X-ray imaging

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Rare Metals 2024年第1期43卷 175-185页

作者： Jin-Xiao zheng Zi-An Zhou Tiao feng Hui Li Cheng-Hua Sun NüWang Yang tian Yong Zhao Shu-Yun Zhou Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Laboratory of Bioinspired Smart Interfacial Science and Technology of the Ministry of Education Beijing Key Laboratory of Bioinspired Energy Materials and DevicesSchool of ChemistryBeijing Advanced Innovation Center for Biomedical EngineeringBeihang UniversityBeijing 100191China Department of Engineering Physics Tsinghua University and Key Laboratory of Particle and Radiation Imaging Ministry of EducationTsinghua UniversityBeijing 100084China e-mail:yangt@***

The underwater X-ray imaging technology development is significant to subaqueous target reconnaissance/detection/identification, subfluvial archaeology,submerged resource exploration, etc. As the core of X-ray imaging detection, the scintillator has been plagued by inherent moisture absorption and decomposition, and strict requirements for seamless packaging and ***, we designed a manganese-doped two-dimensional(2D) perovskite scintillator modified by hydrophobic longchain organic amine through the combination of component and doping engineering. The modified perovskites show high water repellency that can be used as an underwater X-ray scintillator. X-ray images of aquatic organisms or other objects with a high spatial resolution of10 lp·mm^(-1) at a big view field(32 mm × 32 mm) were obtained by scintillation screen. This hydrophobic perovskite scintillator based on molecular design is of great promise in underwater X-ray nondestructive testing technology development.

关键词： Two-dimensional perovskite Hydrophobic Scintillators Underwater X-ray imaging Underwater nondestructive testing technology

Immunobiology of COVID-19: Mechanistic and therapeutic insights from animal models

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Zoological Research 2024年第4期45卷 747-766页

作者： Hong-Yi zheng tian-Zhang Song Yong-Tang zheng State Key Laboratory of Genetic Evolution&Animal Models KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common DiseasesCenter for Biosafety Mega-ScienceKunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China National Resource Center for Non-Human Primates National Research Facility for Phenotypic&Genetic Analysis of Model Animals(Primate Facility)Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650107China

The distribution of the immune system throughout the body complicates in vitro assessments of coronavirus disease 2019(COVID-19)immunobiology,often resulting in a lack of reproducibility when extrapolated to the whole ***,developing animal models is imperative for a comprehensive understanding of the pathology and immunology of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)*** review summarizes current progress related to COVID-19 animal models,including non-human primates(NHPs),mice,and hamsters,with a focus on their roles in exploring the mechanisms of immunopathology,immune protection,and long-term effects of SARS-CoV-2 infection,as well as their application in immunoprevention and immunotherapy of SARS-CoV-2 *** among these animal models and their specific applications are also highlighted,as no single model can fully encapsulate all aspects of *** effectively address the challenges posed by COVID-19,it is essential to select appropriate animal models that can accurately replicate both fatal and non-fatal infections with varying courses and *** animal model libraries and associated research tools is key to resolving the global COVID-19 pandemic,serving as a robust resource for future emerging infectious diseases.

关键词： SARS-CoV-2 COVID-19 Animal models Infection immunology Immunotherapy