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Frontiers of Information technology & Electronic Engineering 2024年第8期25卷 1134-1144页

作者： Yitao YANG Lidong ZHANG School of Science Tianjin University of TechnologyTianjin 300384China

This article investigates the event-triggered adaptive neural network(NN)tracking control problem with deferred asymmetric time-varying(DATV)output *** deal with the DATV output constraints,an asymmetric time-varying barrier Lyapunov function(ATBLF)is first built to make the stability analysis and the controller construction ***,an event-triggered adaptive NN tracking controller is constructed by incorporating an error-shifting function,which ensures that the tracking error converges to an arbitrarily small neighborhood of the origin within a predetermined settling time,consequently optimizing the utilization of network *** is theoretically proven that all signals in the closed-loop system are semi-globally uniformly ultimately bounded(SGUUB),while the initial value is outside the constraint ***,a single-link robotic arm(SLRA)application example is employed to verify the viability of the acquired control algorithm.

关键词： Adaptive control Deferred asymmetric time-varying output constraints Error-shifting function Event-triggered control

Coexisting fast–slow dendritic traveling waves in a 3D-array electric field coupled neuronal network

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Chinese Physics B 2024年第6期33卷 614-626页

作者：魏熙乐任泽宇卢梅丽樊亚琴常思远 The tianjin Key Laboratory of Process Measurement and Control School of Electrical and Information EngineeringTianjin UniversityTianjin 300072China School of Information technology Engineering Tianjin University of Technology and EducationTianjin 300074China

Coexistence of fast and slow traveling waves without synaptic transmission has been found in hhhippocampal tissues,which is closely related to both normal brain activity and abnormal neural activity such as epileptic discharge. However, the propagation mechanism behind this coexistence phenomenon remains unclear. In this paper, a three-dimensional electric field coupled hippocampal neural network is established to investigate generation of coexisting spontaneous fast and slow traveling waves. This model captures two types of dendritic traveling waves propagating in both transverse and longitude directions: the N-methyl-D-aspartate(NMDA)-dependent wave with a speed of about 0.1 m/s and the Ca-dependent wave with a speed of about 0.009 m/s. These traveling waves are synaptic-independent and could be conducted only by the electric fields generated by neighboring neurons, which are basically consistent with the in vitro data measured experiments. It is also found that the slow Ca wave could trigger generation of fast NMDA waves in the propagation path of slow waves whereas fast NMDA waves cannot affect the propagation of slow Ca waves. These results suggest that dendritic Ca waves could acted as the source of the coexistence fast and slow waves. Furthermore, we also confirm the impact of cellular spacing heterogeneity on the onset of coexisting fast and slow waves. The local region with decreasing distances among neighbor neurons is more liable to promote the onset of spontaneous slow waves which, as sources, excite propagation of fast waves. These modeling studies provide possible biophysical mechanisms underlying the neural dynamics of spontaneous traveling waves in brain tissues.

关键词： hippocampal network epileptiform dendritic oscillation traveling wave electric field coupling

A semantic segmentation-based underwater acoustic image transmission framework for cooperative SLAM

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Defence technology（防务技术） 2024年第3期33卷 339-351页

作者： Jiaxu Li Guangyao Han Shuai Chang Xiaomei Fu School of Marine Science and technology Tianjin UniversityTianjin 300072China

With the development of underwater sonar detection technology,simultaneous localization and mapping(SLAM)approach has attracted much attention in underwater navigation field in recent *** the weak detection ability of a single vehicle limits the SLAM performance in wide ***,cooperative SLAM using multiple vehicles has become an important research *** key factor of cooperative SLAM is timely and efficient sonar image transmission among underwater ***,the limited bandwidth of underwater acoustic channels contradicts a large amount of sonar image *** is essential to compress the images before ***,deep neural networks have great value in image compression by virtue of the powerful learning ability of neural networks,but the existing sonar image compression methods based on neural network usually focus on the pixel-level information without the semantic-level *** this paper,we propose a novel underwater acoustic transmission scheme called UAT-SSIC that includes semantic segmentation-based sonar image compression(SSIC)framework and the joint source-channel codec,to improve the accuracy of the semantic information of the reconstructed sonar image at the *** SSIC framework consists of Auto-Encoder structure-based sonar image compression network,which is measured by a semantic segmentation network's *** that sonar images have the characteristics of blurred target edges,the semantic segmentation network used a special dilated convolution neural network(DiCNN)to enhance segmentation accuracy by expanding the range of receptive *** joint source-channel codec with unequal error protection is proposed that adjusts the power level of the transmitted data,which deal with sonar image transmission error caused by the serious underwater acoustic *** results demonstrate that our method preserves more semantic information,with advantages over existing methods at the sa

关键词： Semantic segmentation Sonar image transmission Learning-based compression

Effect of applied electric fields on supralinear dendritic integration of interneuron

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Chinese Physics B 2024年第2期33卷 84-95页

作者：樊亚琴魏熙乐卢梅丽伊国胜 tianjin Key Laboratory of Process Measurement and Control School of Electrical and Information EngineeringTianjin UniversityTianjin 300072China School of Information technology Engineering Tianjin University of Technology and EducationTianjin 300222China

Evidences show that electric fields(EFs)induced by the magnetic stimulation could modulates brain activities by regulating the excitability of GABAergic ***,it is still unclear how and why the EF-induced polarization affects the interneuron response as the interneuron receives NMDA synaptic *** the key role of NMDA receptor-mediated supralinear dendritic integration in neuronal computations,we suppose that the applied EFs could functionally modulate interneurons’response via regulating dendritic *** first,we build a simplified multi-dendritic circuit model with inhomogeneous extracellular potentials,which characterizes the relationship among EF-induced spatial polarizations,dendritic integration,and somatic *** performing model-based singular perturbation analysis,it is found that the equilibrium point of fast subsystem can be used to asymptotically depict the subthreshold input–output(sI/O)relationship of dendritic *** predicted that EF-induced strong depolarizations on the distal dendrites reduce the dendritic saturation output by reducing driving force of synaptic input,and it shifts the steep change of sI/O curve left by reducing stimulation threshold of triggering NMDA ***,the EF modulation prefers the global dendritic integration with asymmetric scatter distribution of NMDA ***,we identify the respective contribution of EF-regulated dendritic integration and EF-induced somatic polarization to an action potential generation and find that they have an antagonistic effect on AP generation due to the varied NMDA spike threshold under EF stimulation.

关键词： GABAergic interneuron electrical field supralinear dendritic integration action potential generation

Effects of orientation on the fatigue crack growth behaviors of the ZK60 magnesium alloy in air and PBS

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Journal of Magnesium and Alloys 2024年第1期12卷 281-294页

作者： Jiaqi Hu Zheng Liu Zuoliang Ning Hong Gao School of Chemical Engineering and technology Tianjin UniversityTianjin 300072China tianjin Key Laboratory of Chemical Process Safety and Equipment technology Tianjin 300072China

Strong anisotropic corrosion and mechanical properties caused by specimen orientations greatly limit the applications of wrought magnesium *** investigate the influences of specimen orientation,the corrosion tests and(corrosion)fatigue crack growth tests were *** rolled and transverse surfaces of the materials show distinct corrosion rate differences in the stable corrosion stage,but the truth is the opposite for the initial stage of *** air,specimen orientations have a significant influence on the plastic deformation mechanisms near the crack tip,which results in different fatigue fracture surfaces and cracking *** with R-T specimens,N-T specimens show a slower fatigue crack growth(FCG)rate in air,which can be attributed to crack closure effects and deformation twinning near the crack *** corrosion environment will not significantly change the main plastic deformation mechanisms for the same type of ***,the FCG rate in phosphate buffer saline(PBS)is one order of magnitude higher than that in air,which is caused by the combined effects of hydrogen-induced cracking and anodic *** to the similar corrosion rates at crack tips,the specimens with different orientations display close FCG rates in PBS.

关键词： Magnesium alloy Orientation Corrosion Fatigue crack growth

Permeable and robust polymer-silica hybrid armor on cell catalyst for sustainable biomanufacturing

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颗粒学报（英文版） 2024年第9期92卷 106-112页

作者： Yiran Cheng Zhenhua Wu Boyu Zhang Jiaxu Zhang Jiafu Shi Zhongyi Jiang School of Environmental Science and Engineering Tianjin UniversityTianjin300072China School of Environmental Science and Engineering Tianjin UniversityTianjin300072China Key Laboratory for Green Chemical technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China

Inactivated cell catalysis is one of several central techniques in green biomanufacturing ***,the instability and leakage of enzymes in inactivated cell severely restrict the practical applications of inactivated cell *** armor on the surface of inactivated cells affords a feasible and effective strategy to enhance the stability of cells while commonly lowering the ***,polymer-silica hybrid armor(PSHA)is directly generated on the surface of enzyme-containing *** branched structure of PEI enables higher porosity of cell@PSHA,exhibiting 1.52-fold enhancement in substrate permeability by contrast with cell@silica armor(SA).The electrostatic interactions(NH3+with O-)and hydrogen bonding(N…H or O…H)interactions between structural units enables higher stability of cell@PSHA,showing 3.13-fold elevation in Young's modulus compared with cell@*** a result,the cell@PSHA can catalyze continuous conversion of starch to tagatose for 15 batches over 969 h,with an average yield of 77.76 g L-1.

关键词： Biomanufacturing Polymer-silica hybrid armor Starch conversion Tagatose production Whole cell catalysis

Research Progress in the Fabrication of Covalent Organic Framework Membranes for Chemical Separations

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Chinese Journal of Polymer Science 2024年第2期42卷 141-158,I0005页

作者： Cui-Ting Ding Jin-Qiu Yuan Meng-Ying Xie Qing-Yuan Liu Zeng-Guang Yao Shi-Yu Zhang Run-Nan Zhang Hong Wu Zhong-Yi Jiang Key Laboratory for Green Chemical technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China Zhejiang Institute of tianjin university NingboZhejiang315201China Haihe Laboratory of Sustainable Chemical Transformations Tianjin300192China tianjin Key Laboratory of Membrane Science and Desalination technology Tianjin UniversityTianjin300072China Joint School of National university of Singapore and tianjin university International Campus of Tianjin UniversityBinhai New CityFuzhou350207China

Membrane technology has become one of the most promising separation technologies for its energy saving, high separation efficiency, environmental friendliness, and economic feasibility. Covalent organic frameworks(COFs) with intrinsically high porosity, controllable pore size, uniform pore size distribution and long-range ordered channel structure, have emerged as next-generation materials to fabricate advanced separation membranes. This feature article summarizes some latest studies in the development of pure COF membranes in our lab, including their fabrication and applications in chemical separations. Finally, current challenges facing high-performance COF separation membranes are discussed.

关键词： Covalent organic frameworks Covalent organic framework membranes Water treatment Organic solvent nanofiltration Gas separation

Organic polymorphic crystals with multi-stimuli response:excellent mechanical elasticity,novel two-stage heterotropic photochromism and self-reversible acidichromism

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Science China Materials 2024年第9期67卷 2796-2806页

作者： Yutong Yao Ting Wang Hui Yu Zhicheng Jiang Wenbo Wu Hongtu Zhao Hongchang Wu Na Wang Xin Huang Hongxun Hao National Engineering Research Center of Industrial Crystallization technology School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China Collaborative Innovation Center of Chemical Science and Engineering(tianjin) Tianjin300072China State Key Laboratory of Chemical Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China

Smart multi-stimuli responsive organic materials have become increasingly favored due to their advantages of high stability and easy *** this study,a cyanostilbene derivative((αZ)-2-chloro-α-[(4-methoxyphenyl)methylene]-5-pyridinehyde,TAR)was successfully synthesized,and its polymorphs(TAR-1 and TAR-2)exhibited multiple responsive behaviors under different stimulus ***-1 is supposed to have excellent mechanical properties,while TAR-2 shows fascinating heterotropic photochromism(green-cyan-yellow)under different intensities of ultraviolet(UV)irradiation,which has never been reported in previous *** investigation revealed that this was attributed to different degrees of[2+2]cycloaddition induced by UV *** addition,both polymorphs could be protonated during Trifluoroacetic acid fuming and deprotonate automatically after fuming,accompanied by the significant variation in ***,two scenarios were designed based on their unique stimuli-responsive properties,which proved their promising potential in fields of information security and anti-counterfeiting encryption.

关键词： elastic bending heterotropic photochromism self-reversible acidichromism

CO_(2) hydrogenation to methanol over the copper promoted In_(2)O_(3) catalyst

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Journal of Energy Chemistry 2024年第6期93卷 135-145,I0004页

作者： Rui Zou Chenyang Shen Kaihang Sun Xinbin Ma Zhuoshi Li Maoshuai Li Chang-Jun Liu School of Chemical Engineering and technology Tianjin UniversityTianjin 300350China Collaborative Innovation Center of Chemical Science&Engineering Tianjin UniversityTianjin 300072China

The metal promoted In_(2)O_(3) catalysts for CO_(2) hydrogenation to methanol have attracted wide attention because of their high activity with high methanol ***,there was still no experimental confirmation if copper could be a good promoter for In_(2)O_(3).Herein,the Cu promoted In_(2)O_(3) catalyst was prepared using a deposition-precipitation *** prepared Cu/In_(2)O_(3) catalyst shows significantly higher CO_(2) conversion and space time yield(STY)of methanol,compared to the un-promoted In_(2)O_(3) *** loading of Cu facilitates the activation of both H_(2) and CO_(2) with the interface between the Cu cluster and defective In_(2)O_(3) as the active *** Cu/In_(2)O_(3) catalyst takes the CO hydrogenation pathway for methanol synthesis from CO_(2) *** exhibits a unique size effect on the CO *** temperatures below 250℃,CO adsorption on Cu/In_(2)O_(3) is stronger than that on In_(2)O_(3),causing higher methanol *** increasing temperatu res,the Cu catalyst aggregates,which leads to the formation of weak CO adsorption site and causes a decrease in the methanol *** with other metal promoted In_(2)O_(3) catalysts,it can be concluded that the catalyst with stronger CO adsorption possesses higher methanol selectivity.

关键词： CO_(2)hydrogenation Methanol Cu In_(2)O_(3) CO Selectivity DFT

Research progress on simulation of multiscale mass transfer processes in gas-solid system by computational mass transfer

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Particuology 2024年第7期90卷 478-492页

作者： Xu Li Yaohui Wang Leifu Li Runye Zhang Hailun Ren Wenbin Li Zhongli Tang Donghui Zhang The Research Center of Chemical Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China The Department of Chemical Engineering Tianjin Renai CollegeTianjin 301636China Collaborative Innovation Center of Chemical Science and Engineering(tianjin) School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Particle-fluid system is one of the most popular systems in chemical *** to complex interface structure and high-velocity turbulence,the momentum and mass transfer exhibit nonlinear characteristics,which pose a great challenge for further study and *** solve this problem,computational mass transfer(CMT)emerged and has been proved to be effective in deeply exploring the mass transfer behavior of particle-fluid ***,this paper reviews recent gas-solid numerical studies of turbulence issues from empirical to theoretical,then discusses interphase mass transfer rate models and the interfacial interaction ***,the present study particularly reviews researches on mass transfer process of fixed and fluidized regime by CMT,providing reliable analysis of turbulent anisotropy diffusivity as well as multiscale structure and presenting theoretical instruction for the industrial optimization of mass transfer processes in chemical engineering.

关键词： Fixed bed Fluidized bed Computational mass transfer Turbulent mass diffusion Multiscale Anisotropy