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Time-history performance optimization of flapping wing motion using a deep learning based prediction model

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Chinese Journal of Aeronautics 2024年第5期37卷 317-331页

作者： Tianqi WANG liu liu Jun li lifang ZENG School of Aeronautics and Astronautics Zhejiang UniversityHangzhou 310027China Huanjiang Laboratory Zhuji 311800China

Flapping Wing Micro Aerial Vehicles(FWMAVs)have caused great concern in various fields because of their high efficiency and *** wing motion is a very important factor that affects the performance of the aircraft,and previous works have always focused on the time-averaged performance ***,the time-history performance is equally important in the design of motion mechanism and flight control *** this paper,a time-history performance optimization framework based on deep learning and multi-island genetic algorithm is presented,which is designed in order to obtain the optimal two-dimensional flapping wing ***,the training dataset for deep learning neural network is constructed based on a validated computational fluid dynamics *** aerodynamic surrogate model for flapping wing is obtained after the convergence of *** surrogate model is tested and proved to be able to accurately and quickly predict the time-history curves of lift,thrust and ***,the optimization framework is used to optimize the flapping wing motion in two specific cases,in which the optimized propulsive efficiencies have been improved by over 40%compared with the ***,a dimensionless parameter C_(variation)is proposed to describe the variation of the time-history characteristics,and it is found that C_(variation)of lift varies significantly even under close time-averaged *** the importance of time-history performance in practical applications,the optimization that integrates the propulsion efficiency as well as C_(variation)is carried *** final optimal flapping wing motion balances good time-averaged and time-history performance.

关键词： FWMAV Flapping wing motion Deep learning Unsteady aerodynamic performance Optimization Time-history curve

High Energy Efficiency Dynamic Connected Hybrid Precoding for mm Wave Massive MIMO Systems

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China Communications 2024年第5期21卷 36-44页

作者： Du Ruiyan liu Huajing li Tiangui liu Fulai Lab of Key Technology of Millimeter-wave Large-scale MIMO System Northeastern University at QinhuangdaoQinhuangdao066004China School of Computer Science and Engineering Northeastern UniversityShenyang 110819China

This paper considers a high energy efficiency dynamic connected(HEDC)structure,which promotes the practicability and reduces the power consumption of hybrid precoding system by lowresolution phase shifters(PSs).Based on the proposed structure,a new hybrid precoding algorithm is presented to optimize the energy efficiency,namely,HP-HEDC ***,via a new defined effective optimal precoding matrix,the problem of optimizing the analog switch precoding matrix is formulated as a sparse representation ***,the optimal analog switch precoding matrix can be readily obtained by the branch-and-bound ***,the digital precoding matrix optimization problem is modeled as a dictionary update problem and solved by the method of optimal direction(MOD).Finally,the diagonal entries of the analog PS precoding matrix are optimized by exhaustive search independently since PS and antenna is *** results show that the HEDC structure enjoys low power consumption and satisfactory spectral *** proposed algorithm presents at least 50%energy efficiency improvement compared with other algorithms when the PS resolution is set as 3-bit.

关键词： energy efficiency hybrid precoding mmWave optimized resolution phase shifter

Magnetic and luminescent properties of bifunctional composite Fe_(3)O_(4)@Y_(2)O_(2)S:Eu^(3+)

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Journal of Rare Earths 2024年第8期42卷 1568-1576,I0006页

作者： Zhiqi liang Zhili Zhang liu li Wen Xu Decai li School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBejing100044China Beijing Key Laboratory of Flow and Heat Transfer of Phase Changing in Micro and Small Scale Bejing100044China State Key Laboratory of Tribology Tsinghua UniversityBejing100084China

As a kind of non-destructive testing method,magnetic particle inspection is widely used in the fields of aviation and high-speed *** properties of magnetic fluorescent bifunctional composites,such as fluorescence intensity and magnetic properties,have increasing demands in magnetic particle *** earth compounds offer potential as novel materials for fluorescent magnetic bifunctional composites due to their excellent optical properties and extremely narrow emission *** this work,the rare earth fluorescent material Y_(2)O_(2)S:Eu^(3+) was synthesized by solid-state reaction ***_(3)O_(4)nanoparticles prepared by hydrothermal method were uniformly coated on the Y_(2)O_(2)S:Eu^(3+) particles through physical adsorption of *** obtained Fe_(3)O_(4)@Y_(2)O_(2)S:Eu^(3+) exhibits dark red color under the ultraviolet *** additio n,X-ray diffractio n,morphology,photoluminescence and hyste resis loop of Fe_(3)O_(4)@Y_(2)O_(2)S:Cu^(3+) were *** luminescence mechanism of Y_(2)O_(2)S:Eu^(3+) is described in detail Fe_(3)O_(4)@Y_(2)O_(2)S:Cu^(3+) displays good paramagnetism and has a good controllability under a magnetic *** magnetic particle inspection of Fe_(3)O_(4)@Y_(2)O_(2)S:Eu^(3+) was performed using a 4-pole electromagnet and a test piece *** magnetic fluorescent bifunctional composite presented in this work can be applied for non-destructive testing.

关键词： Bifunctional material Fe_(3)O_(4) Y_(2)O_(2)S:Eu^(3+) Luminescence Solid-state reaction Rare earths

Layer-by-layer fabrication of montmorillonite coating immobilizing Cu_(2)O nanoparticles for continuously catalyzing glycerol to dihydroxyacetone

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Chinese Journal of Chemical Engineering 2024年第4期68卷 263-275页

作者： Kejin li Jiahui liu Dajian li Xiaolan Chen Chunhui Zhou Research Group for Advanced Materials&Sustainable Catalysis(AMSC) State Key Laboratory Breeding Base of Green Chemistry-Synthesis TechnologyCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou 310032China Qing Yang Institute for Industrial Minerals Qingyang 242804China Engineering Research Center of Non-metallic Minerals of Zhejiang Province Zhejiang Institute of Geology and Mineral ResourcesHangzhou 310007China

Microreactors are increasingly used for green and safe chemical processes owing to their benefits of superior mass and heat transfer,increased yield,safety,and simplicity of ***,immobilizing catalysts in microreactors remains *** this investigation,a technique for creating Cu_(2)O/montmorillonite catalyst coating,using electrostatic attraction for layer-by-layer self-assembly,was *** montmorillonite film's morphology and thickness could be efficiently regulated by adjusting the degree of exfoliation and surface charge of montmorillonite,alongside layer-by-layer coating *** Cu_(2)O nanoparticles were immobilized using the flow deposition *** resulting Cu_(2)O@montmorillonite-film-coated capillary microreactor successfully transformed glycerol into *** conversion of glycerol and product selectivity could be controlled by adjusting the molar ratio of reactants,temperature,residence time,and Cu_(2)O *** maximum glycerol conversion observed was 47.6%,with a 27%selectivity toward *** study presents a technique for immobilizing montmorillonite-based catalyst coatings in capillary tubing,which can serve as a foundation for the future application of microreactors in glycerol conversion.

关键词： Microreactor Coating Montmorillonite Glycerol Cu_(2)O

Insight into the adsorption behavior and mechanism of trace impurities from H_(2)O_(2) solution on functionalized zirconia by tuning the structure of amino groups

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 83-94页

作者： Yu Meng Yitong Wang Guozhu li Guozhu liu li Wang Key Laboratory for Green Chemical Technology of Ministry Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Primary,secondary and tertiary amino-functionalized zirconia(ZrO_(2)-NH_(2),ZrO_(2)-NH and ZrO_(2)-N)was synthesized by the postgrafting method for the adsorption removal of typical metallic ions,phosphate and total oxidizable carbon from a real H_(2)O_(2) ***_(2)-NH_(2),ZrO_(2)-NH and ZrO_(2)-N exhibited similar pore sizes and sequentially increased zeta *** adsorption results of single and binary simulated solutions showed that the removal efficiency increased in the order of Fe^(3+)>Al^(3+)>Ca^(2+)>Na^(+).There is competitive adsorption between metallic ions,and Fe^(3+) has an advantage over the other metals,with a removal efficiency of 90.7%.The coexisting phosphate could promote the adsorption of metallic ions,while total oxidizable carbon had no effect on *** adsorption results of the real H_(2)O_(2)solution showed that ZrO_(2)-NH_(2) exhibited the best adsorption affinity for metallic ions,as did phosphate and total oxidizable carbon,with a total adsorption capacity of 120.9 mg·g_(-1).Density functional theory calculations revealed that the adsorption process of metallic ions involves electron transfer from N atoms to metals and the formation of N-metal bonds.

关键词： adsorption metallic ion phosphate total oxidizable carbon zirconia H_(2)O_(2)

Engineered spidroin-derived high-performance fibers for diverse applications

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Nano Research 2024年第2期17卷 492-502页

作者： Dawen Qin Jingjing li Huanrong li Hongjie Zhang Kai liu National-Local Joint Engineering Laboratory for Energy Conservation in Chemical Process Integration and Resources Utilization Tianjin Key Laboratory of Chemical Process SafetySchool of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Engineering Research Center of Advanced Rare Earth Materials Ministry of EducationDepartment of ChemistryTsinghua UniversityBeijing 100084China University of Science and Technology of China Hefei 230026China

Spider silks are well known for their exceptional mechanical properties that are tougher than Kevlar and ***,the restricted production amounts from their native sources limit applications of spider *** the decades,there have been significant interests in fabricating man-made silk fibers with comparable performance to natural silks,inspiring many efforts both for biosynthesizing recombinant spider silk proteins(spidroins)in amenable heterologous hosts and biomimetic spinning of artificial spider *** strategies provide promising routes to produce high-performance and functionally optimized fibers with diverse ***,we summarize the hosts that have been applied to produce recombinant *** addition,the fabrication and mechanical properties of recombinant spidroin fibers and their composite fibers are also ***,we demonstrate the applications of recombinant spidroin-based ***,facing the challenges in biosynthesis,scalable production,and hierarchical assembly of high-performance recombinant spidroins,we give a summary and perspective on future development.

关键词： spider silk recombinant spidroin heterologous expression fiber fabrication mechanical property

Synergic action of linear dispersion, second-order nonlinearity, and third-order nonlinearity in shaping the spectral profile of a femtosecond pulse transporting in a lithium niobate crystal

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Photonics Research 2024年第4期12卷 774-783页

作者： liHONG HONG YUANYUAN liu ZHI-YUAN li State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China

We present a detailed theoretical and numerical analysis on the temporal-spectral-spatial evolution of a highpeak-power femtosecond laser pulse in two sets of systems:a pure lithium niobate(LN)plate and a periodically poled lithium niobate(PPLN)*** develop a modified unidimensional pulse propagation model that considers all the prominent linear and nonlinear processes and carried out the simulation process based on an improved split-step Fourier transformation *** theoretically analyze the synergic action of the linear dispersion effect,the second-order nonlinearity(2nd-NL)second-harmonic generation(SHG)effect,and the third-order nonlinearity(3rd-NL)self-phase modulation(SPM)effect,and clarify the physical mechanism underlying the peculiar and diverse spectral broadening patterns previously reported in LN and PPLN thin plate *** analysis and discussion provides a deeper insight into the synergetic contribution of these linear and nonlinear effects brought about by the interaction of a femtosecond laser pulse with the LN nonlinear crystal and helps to draw a picture to fully understand these fruitful optical physical processes,phenomena,and laws.

关键词： pulse nonlinearity lithium

Prohibitin 1 inhibits cell proliferation and induces apoptosis via the p53-mediated mitochondrial pathway in vitro

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World Journal of Gastrointestinal Oncology 2024年第2期16卷 398-413页

作者： Juan-Juan Shi Yi-Kai Wang Mu-Qi Wang Jiang Deng Ning Gao Mei li Ya-Ping li Xin Zhang Xiao-li Jia Xiong-Tao liu shuang-Suo Dang Wen-Jun Wang Department of Infectious Diseases The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi'an 710004Shaanxi ProvinceChina Department of Operating Room The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi'an 710004Shaanxi ProvinceChina

BACKGROUND Prohibitin 1(PHB1)has been identified as an antiproliferative protein that is highly conserved and ubiquitously expressed,and it participates in a variety of essential cellular functions,including apoptosis,cell cycle regulation,prolifera-tion,and *** evidence indicates that PHB1 may play an important role in the progression of hepatocellular carcinoma(HCC).However,the role of PHB1 in HCC is *** To investigate the effects of PHB1 on the proliferation and apoptosis of human HCC cells and the relevant mechanisms in *** HCC patients and healthy individuals were enrolled in this study according to the inclusion and exclusion criteria;then,PHB1 levels in the sera and liver tissues of these participates were determined using EliSA,RT-PCR,and *** HepG2 and SMMC-7721 cells were transfected with the pEGFP-PHB1 plasmid and PHB1-specific shRNA(shRNA-PHB1)for 24-72 *** prolif-eration was analysed with an MTT *** cycle progression and apoptosis were analysed using flow cytometry(FACS).The mRNA and protein expression levels of the cell cycle-related molecules p21,Cyclin A2,Cyclin E1,and CDK2 and the cell apoptosis-related molecules cytochrome C(Cyt C),p53,Bcl-2,Bax,caspase 3,and caspase 9 were measured by real-time PCR and Western blot,*** Decreased levels of PHB1 were found in the sera and liver tissues of HCC patients compared to those of healthy individuals,and decreased PHB1 was positively correlated with low differentiation,TNM stage III-IV,and alpha-fetoprotein≥400μg/*** of PHB1 significantly inhibited human HCC cell proliferation in a time-dependent *** revealed that the overexpression of PHB1 arrested HCC cells in the G0/G1 phase of the cell cycle and induced *** proportion of cells in the G0/G1 phase was significantly increased and the proportion of cells in the S phase was decreased in HepG2 cells that were transfected with pEGFP-PHB1 compar

关键词： Prohibitin 1 Hepatocellular carcinoma cells Apoptosis Cell cycle Mitochondrial pathway

Prediction of cell-cell communication patierns of dorsal root ganglion cells: single-cell RNA sequencing data analysis

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Neural Regeneration Research 2024年第6期19卷 1367-1374页

作者： Yanna lian Cheng Wu li liu Xiangyao li National Health Commission and Chinese Academy of Medical Sciences Key Laboratory of Medical Neurobiology Ministry of Education Frontier Science Center for Brain Research and Brain-Machine Integration School of Brain Science and Brain Medicine Zhejiang University International Institutes of Medicine the Fourth Affiliated Hospital of Zhejiang University School of Medicine Zhejiang University-University of Edinburgh Institute Zhejiang University School of Medicine Zhejiang University 4. Biomedical Sciences College of Medicine and Veterinary Medicine The University of Edinburgh Core Facilities of the School of Medicine Zhejiang University

Dorsal root ganglion neurons transmit peripheral somatic information to the central nervous system, and dorsal root ganglion neuron excitability affects pain perception. Dorsal root ganglion stimulation is a new approach for managing pain sensation. Knowledge of the cell-cell communication among dorsal root ganglion cells may help in the development of new pain and itch management strategies. Here, we used the single-cell RNA-sequencing(scRNA-seq) database to investigate intercellular communication networks among dorsal root ganglion cells. We collected scRNA-seq data from six samples from three studies, yielding data on a total of 17,766 cells. Based on genetic profiles, we identified satellite glial cells, Schwann cells, neurons, vascular endothelial cells, immune cells, fibroblasts, and vascular smooth muscle cells. Further analysis revealed that eight types of dorsal root ganglion neurons mediated proprioceptive, itch, touch, mechanical, heat, and cold sensations. Moreover, we predicted several distinct forms of intercellular communication among dorsal root ganglion cells, including cell-cell contact, secreted signals, extracellular matrix, and neurotransmitter-mediated signals. The data mining predicted that Mrgpra3-positive neurons robustly express the genes encoding the adenosine Adora2b(A2B) receptor and glial cell line-derived neurotrophic factor family receptor alpha 1(GFRα-1). Our immunohistochemistry results confirmed the coexpression of the A2B receptor and GFRα-1. Intrathecal injection of the A2B receptor antagonist PSB-603 effectively prevented histamine-induced scratching behaviour in a dose-dependent manner. Our results demonstrate the involvement of the A2B receptor in the modulation of itch sensation. Furthermore, our findings provide insight into dorsal root ganglion cell-cell communication patterns and mechanisms. Our results should contribute to the development of new strategies for the regulation of dorsal root ganglion excitability.

关键词： cell-cell communications CellChat dorsal root ganglion scRNA-Seq database