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Graphene reinforced nanoarchitectonics of 3D interconnected magnetic-dielectric frameworks for high-efficient and anti-corrosive microwave absorbers

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Journal of Materials Science & Technology 2024年第1期168卷 194-207页

作者： Chenchen liu Xiaofang Feng Shuning liu Guo Lin Zhongxiang Bai Lingling Wang Ke Zhu Xiulan Li Xiaobo liu School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu611731China Sichuan Province Engineering Technology Research Center of Novel CN Polymeric Materials Chengdu611731China School of Chemical Engineering Northwest UniversityXi’an710069China Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology School of Environmental Science and EngineeringSun Yat-sen UniversityGuangzhou510275China

The combination of high efficiency and environmental stability is vital to promote the commercial appli-cations of microwave absorption(MA)materials,yet remains challenging in the absence of facile ***,we put forward a graphene-reinforced construct approach for one-pot synthesis of 3D intercon-nected magnetic-dielectric frameworks via pre-functionalization and subsequent *** in-teractions among discrete precursors are capable of manipulating the confined growth and interfacial *** enhancements in MA properties are triggered in a straightforward manner us-ing ultralow feeding fractions of graphene oxide *** minimum reflection loss is up to-60.1 dB(99.9999%wave absorption)and the effective absorption bandwidth reaches 5.9 GHz(almost covering the Ku band).Remarkably,based on the optimization by ultralow concentrations of graphene,the as-prepared nanoarchitecture simultaneously integrates strong absorption,broad bandwidth,and low matching *** embedded graphene nanosheets serve as high-speed electron transmission channels and hollow resonance cavities,facilitating multimode attenuations and impedance-matching ***-while,the graphene-reinforced framework suppresses the corrosion of magnetic components,whose cor-rosion rate reduces by an order of *** study provides a simple procedure to boost magnetic-dielectric absorbers for comprehensive MA performances and enhanced corrosion resistance.

关键词： 3D Magnetic-dielectric framework Graphene nanosheet Microwave absorption Anti-corrosion

A stable staggered-grid finite-difference scheme for acoustic modeling beyond conventional stability limit

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Petroleum Science 2024年第1期21卷 182-194页

作者： Jing-Yi Xu Yang liu National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing 102249China China University of Petroleum(Beijing) Karamay CampusKaramay 834000XinjiangChina

Staggered-grid finite-difference(SGFD)schemes have been widely used in acoustic wave modeling for geophysical *** improved methods are proposed to enhance the accuracy of numerical ***,these methods are inevitably limited by the maximum Courant-Friedrichs-Lewy(CFL)numbers,making them unstable when modeling with large time sampling intervals or small grid *** solve this problem,we extend a stable SGFD scheme by controlling SGFD dispersion relations and maximizing the maximum CFL ***,to improve modeling stability,we minimize the error between the FD dispersion relation and the exact relation in the given wave-number region,and make the FD dispersion approach a given function outside the given wave-number area,thus breaking the conventional limits of the maximum CFL ***,to obtain high modeling accuracy,we use the SGFD scheme based on the Remez algorithm to compute the FD *** addition,the hybrid absorbing boundary condition is adopted to suppress boundary reflections and we find a suitable weighting coefficient for the proposed *** derivation and numerical modeling demonstrate that the proposed scheme can maintain high accuracy in the modeling process and the value of the maximum CFL number of the proposed scheme can exceed that of the conventional SGFD scheme when adopting a small maximum effective wavenumber,indicating that the proposed scheme improves stability during the modeling.

关键词： Acoustic wave Staggered-grid finite-difference(SGFD) modeling Courant-friedrichs-lewy(CFL)number Stability

Data-driven evacuation and rescue traffic optimization with rescue contraflow control

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Journal of Safety Science and Resilience 2024年第1期5卷 1-12页

作者： Zheng liu Jialin liu Xuecheng Shang Xingang Li School of Management Engineering Zhengzhou University of AeronauticsZhengzhou 450046China Collaborative Innovation Center for Aviation Economy Development of Henan Province Zhengzhou University of AeronauticsZhengzhou 450046China School of Systems science Beijing Jiaotong UniversityBeijing 100044China Key Laboratory of Transport Industry of Big Data Application Technologies for Comprehensive Transport Beijing Jiaotong UniversityBeijing 100044China School of Transportation Engineering Shandong Jianzhu UniversityJinan 250101China

In response to local sudden disasters,e.g.,high-rise office or residential building fire disasters,road occupation can cause conflicts,and traffic directions may be opposite between evacuation vehicles and rescue vehicles;moreover,lane contraflow can be adopted to meet these surge traffic ***,lane contraflow that provides more roads for rescue vehicles reduces the traffic supply in the evacuation *** is unclear how to control the number of contraflow roads used by rescue vehicles to coordinate evacuation and rescue traffic ***,we adjust the critical rescue traffic volume of reversing the normal road traffic direction to control rescue ***,we propose a multiobjective mixed integer linear programming formulation for evacuation and rescue traffic ***,considering that the upper limit of the critical rescue traffic volume is unknown and that the proposed formulation includes multiple objectives and multi-priority vehicle classes,a three-stage solving algorithm is ***,a large-scale evacuation and rescue traffic optimization result dataset is obtained for the Nguyen–Dupuis road network,and the impact of different rescue contraflow control plans on evacuation and rescue traffic is studied based on data-driven sta-tistical *** results show that by adjusting the optimal rescue traffic route,the critical rescue traffic volume for reversing the normal road traffic direction can reduce the interference of rescue traffic to evacuation traffic operation performance without reducing rescue traffic operation performance,and can be used to coor-dinate evacuation and rescue traffic operation under rescue contraflow.

关键词： Evacuation and rescue traffic optimization Rescue contraflow control Multiobjective mixed integer linear programming Three-stage solving algorithm Data-driven statistical analysis

Research on dynamic measurement method of speckle in laser display

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Optoelectronics Letters 2024年第6期20卷 360-366页

作者： liu Hong liu Yaning ZHANG Xiaoyu School of Electronics Information Shanghai Dianji UniversityShanghai 201306China

Laser display technology is the most promising display technology in the market and is widely used in many fields. However, laser speckle has been troubling the application and expansion of this technology in some fields. In order to better evaluate the speckle, speckle measurement methods must be studied. In this study, a dynamic measurement method for laser speckles is proposed according to the optical superposition characteristics of speckle, which can reduce the influence of non-coherent factors on the speckle measurement results. The feasibility of the dynamic speckle measurement method is verified by designing an experimental scheme.

关键词： Research on dynamic measurement method of speckle in laser display

Estimation of unfrozen water content of saturated sandstones using nuclear magnetic resonance, mercury intrusion porosimetry, and ultrasonic tests

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3465-3484页

作者： Fei liu Shibing Huang Gang liu Shilin Yu School of Resources and Environmental Engineering Wuhan University of Science and TechnologyWuhan430081China Hubei Key Laboratory for Efficient Utilization and Agglomeration of Metallurgic Mineral Resources Wuhan University of Science and TechnologyWuhan430081China

The unfrozenwater content(UWC)is a crucial parameter that affects the strength and thermal properties of rocks in relation to engineering construction and geological disasters in cold *** this study,three different methods were employed to test and estimate the UWC of saturated sandstones,including nuclear magnetic resonance(NMR),mercury intrusion porosimetry(MIP),and ultrasonic *** NMR method enabled the direct measurement of the UWC of sandstones using the free induction decay(FID).The MIP method was used to analyze the pore structures of sandstones,with the UWC subsequently calculated based on pore ice ***,the MIP test constituted an indirect measurement ***,a correlation was established between the P-wave velocity and the UWC of these sandstones based on the mixture theory,which could be employed to estimate the UWC as an empirical *** methods demonstrated that the UWC initially exhibited a rapid decrease from 0C to5C and then generally became constant beyond20***,these test methods had different *** NMR method was used to directly and accurately calculate the UWC in the ***,the cost and complexity of NMR equipment have precluded its use in the *** UWC can be effectively estimated by the MIP test,but the estimation accuracy is influenced by the ice crystallization process and the pore size *** P-wave velocity has been demonstrated to be a straightforward and practical empirical parameter and was utilized to estimate the UWC based on the mixture *** method may be more suitable in the *** methods confirmed the existence of a hysteresis phenomenon in the freezing-thawing *** average hysteresis coefficient was approximately 0.538,thus validating the GibbseThomson *** study not only presents alternative methodologies for estimating the UWC of saturated sandstones but also contribute to our understanding of the freezin

关键词： Unfrozen water content(UWC) Nuclear magnetic resonance(NMR) Mercury intrusion porosimetry(MIP) Pore structures P-wave velocity Sandstone

FADSF:A Data Sharing Model for Intelligent Connected Vehicles Based on Blockchain Technology

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Computers, Materials & Continua 2024年第8期80卷 2351-2362页

作者： Yan Sun Caiyun liu Jun Li Yitong liu Data Security Institute China Industrial Control Systems Cyber Emergency Response TeamBeijing100040China

With the development of technology,the connected vehicle has been upgraded from a traditional transport vehicle to an information terminal and energy storage *** data of ICV(intelligent connected vehicles)is the key to organically maximizing their ***,in the context of increasingly strict global data security supervision and compliance,numerous problems,including complex types of connected vehicle data,poor data collaboration between the IT(information technology)domain and OT(operation technology)domain,different data format standards,lack of shared trust sources,difficulty in ensuring the quality of shared data,lack of data control rights,as well as difficulty in defining data ownership,make vehicle data sharing face a lot of problems,and data islands are *** study proposes FADSF(Fuzzy Anonymous Data Share Frame),an automobile data sharing scheme based on *** data holder publishes the shared data information and forms the corresponding label storage on the *** data demander browses the data directory information to select and purchase data assets and verify *** data demander selects and purchases data assets and verifies them by browsing the data directory ***,this paper designs a data structure Data Discrimination Bloom Filter(DDBF),making complaints about illegal *** the number of data complaints reaches the threshold,the audit traceability contract is triggered to punish the illegal data publisher,aiming to improve the data quality and maintain a good data sharing *** this paper,based on Ethereum,the above scheme is tested to demonstrate its feasibility,efficiency and security.

关键词： Blockchain connected vehicles data sharing smart contracts credible traceability

Deep Global Multiple-Scale and Local Patches Attention Dual-Branch Network for Pose-Invariant Facial Expression Recognition

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 405-440页

作者： Chaoji liu Xingqiao liu Chong Chen Kang Zhou School of Electrical and Information Engineering Jiangsu UniversityZhenjiang212013China School of Electrical Engineering Yancheng Institute of TechnologyYancheng224051China

Pose-invariant facial expression recognition(FER)is an active but challenging research topic in computer *** with the involvement of diverse observation angles,FER makes the training parameter models inconsistent from one view to *** study develops a deep global multiple-scale and local patches attention(GMS-LPA)dual-branch network for pose-invariant FER to weaken the influence of pose variation and selfocclusion on recognition *** this research,the designed GMS-LPA network contains four main parts,i.e.,the feature extraction module,the global multiple-scale(GMS)module,the local patches attention(LPA)module,and the model-level fusion *** feature extraction module is designed to extract and normalize texture information to the same *** GMS model can extract deep global features with different receptive fields,releasing the sensitivity of deeper convolution layers to pose-variant and *** LPA module is built to force the network to focus on local salient features,which can lower the effect of pose variation and self-occlusion on recognition ***,the extracted features are fused with a model-level strategy to improve recognition *** experimentswere conducted on four public databases,and the recognition results demonstrated the feasibility and validity of the proposed methods.

关键词： Pose-invariant FER global multiple-scale(GMS) local patches attention(LPA) model-level fusion

Strategies and opportunities of micro/nano delivery systems for targeted therapy of ulcerative colitis:Focus on underlying mechanisms and future perspectives

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Chinese Chemical Letters 2024年第2期35卷 118-130页

作者： Zihan liu Han liu Jialing Cheng Hongliang Wang Yanfang Yang Jun Ye Yuling liu State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences & Peking Union Medical CollegeBeijing 100050China Beijing Key Laboratory of Drug Delivery Technology and Novel Formulation Institute of Materia MedicaChinese Academy of Medical Sciences & Peking Union Medical CollegeBeijing 100050China

Ulcerative colitis(UC)is a common progressive inflammatory disease whose incidence has increased rapidly in recent years,and can develop into colorectal cancer in severe *** are currently no adequate or effective treatments for UC due to the fact that some patients have found suboptimal results after repeated administration,while others have experienced adverse *** the rapid development of nanotechnology,developing innovative colon-targeting platforms is essential to improving efficacy,reducing side effects,and improving patient *** this review,we summarize the pathophysiological characteristics of UC and the most recent status of numerous nanodrug delivery systems based on different targeting mechanisms in treating ***,intravenous,and rectal drug delivery nanoparticles targeting the colon are discussed,which can provide ideas for the design of colon-targeting nanoparticles for the treatment of colon diseases,especially for the treatment of *** but not least,we provide a glimpse into the future of colon-targeted delivery systems,as well as future advancements in the field.

关键词： Ulcerative colitis Physiological characteristics Colon-specific drug delivery Mechanisms of action Targeted therapy of UC

Transplantation of fibrin-thrombin encapsulated human induced neural stem cells promotes functional recovery of spinal cord injury rats through modulation of the microenvironment

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Neural Regeneration Research 2024年第2期19卷 440-446页

作者： Sumei liu Baoguo liu Qian Li Tianqi Zheng Bochao liu Mo Li Zhiguo Chen Cell Therapy Center Beijing Institute of GeriatricsXuanwu HospitalCapital Medical UniversityNational Clinical Research Center for Geriatric Diseasesand Key Laboratory of Neurodegenerative DiseasesMinistry of EducationBeijingChina Center of Neural Injury and Repair Beijing Institute for Brain DisordersBeijingChina Center of Parkinson’s Disease Beijing Institute for Brain DisordersBeijingChina

Recent studies have mostly focused on engraftment of cells at the lesioned spinal cord,with the expectation that differentiated neurons facilitate *** a few studies have attempted to use transplanted cells and/or biomaterials as major modulators of the spinal cord injury ***,we aimed to investigate the role of microenvironment modulation by cell graft on functional recovery after spinal cord *** neural stem cells reprogrammed from human peripheral blood mononuclear cells,and/or thrombin plus fibrinogen,were transplanted into the lesion site of an immunosuppressed rat spinal cord injury ***,Beattie and Bresnahan score,electrophysiological function,and immunofluorescence/histological analyses showed that transplantation facilitates motor and electrophysiological function,reduces lesion volume,and promotes axonal neurofilament expression at the lesion *** of the graft and niche components revealed that although the graft only survived for a relatively short period(up to 15 days),it still had a crucial impact on the ***,induced neural stem cells and human fibrin reduced the number of infiltrated immune cells,biased microglia towards a regenerative M2 phenotype,and changed the cytokine expression profile at the lesion ***-induced changes of the microenvironment during the acute and subacute stages might have disrupted the inflammatory cascade chain reactions,which may have exerted a long-term impact on the functional recovery of spinal cord injury rats.

关键词： biomaterial fibrinogen functional recovery induced neural stem cell transplantation microenvironment microglia spinal cord injury thrombin