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Experimental study of solid-liquid origami composite structures with improved impact resistance

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 118-123页

作者： Shuheng Wang Zhanyu Wang Bei Wang Zhi liu Yunzhu Ni Wuxing Lai Shan Jiang Yong An Huang AML Department of Engineering MechanicsLaboratory of Flexible Electronics TechnologyTsinghua UniversityBeijing 100084China Institute of Advanced Structure Technology Beijing Key Laboratory of Lightweight Multi-functional Composite Materials and StructuresBeijing Institute of TechnologyBeijing 100081China Hangzhou Institute of Technology Xidian UniversityHangzhou 311200China Nanjing Research Institude of Electronics Technology Nanjing 210039China The Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

In this paper,a liquid-solid origami composite design is proposed for the improvement of impact *** this design strategy,Kresling origami composite structures with different fillings were designed and fabricated,namely air,water,and shear thickening fluid(STF).Quasi-static compression and drop-weight impact experiments were carried out to compare and reveal the static and dynamic mechanical behavior of these *** results from drop-weight impact experiments demonstrated that the solid-liquid Kresling origami composite structures exhibited superior yield strength and reduced peak force when compared to their empty ***,the Kresling origami structures filled with STF exhibited significantly heightened yield strength and reduced peak *** example,at an impact velocity of 3 m/s,the yield strength of single-layer STF-filled Kresling origami structures increased by 772.7%and the peak force decreased by 68.6%.This liquid-solid origami composite design holds the potential to advance the application of origami structures in critical areas such as aerospace,intelligent protection and other important *** demonstrated improvements in impact resistance underscore the practical viability of this approach in enhancing structural performance for a range of applications.

关键词： Solid-liquid design Origami structure Impact resistance Shear thickening fluid

The Predictability Limit of Oceanic Mesoscale Eddy Tracks in the South China Sea

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Advances in Atmospheric Sciences 2024年第9期41卷 1661-1679页

作者： Hailong liu Pingxiang CHU Yao MENG Mengrong DING Pengfei LIN Ruiqiang DING Pengfei WANG Weipeng ZHENG LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Laoshan Laboratory Qingdao 266237China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Marine Science and Technology College Zhejiang Ocean UniversityZhoushan 316022China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100872China Center for Monsoon System Research(CMSR) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100190China

Employing the nonlinear local Lyapunov exponent (NLLE) technique, this study assesses the quantitative predictability limit of oceanic mesoscale eddy (OME) tracks utilizing three eddy datasets for both annual and seasonal means. Our findings reveal a discernible predictability limit of approximately 39 days for cyclonic eddies (CEs) and 44 days for anticyclonic eddies (AEs) within the South China Sea (SCS). The predictability limit is related to the OME properties and seasons. The long-lived, large-amplitude, and large-radius OMEs tend to have a higher predictability limit. The predictability limit of AE (CE) tracks is highest in autumn (winter) with 52 (53) days and lowest in spring (summer) with 40 (30) days. The spatial distribution of the predictability limit of OME tracks also has seasonal variations, further finding that the area of higher predictability limits often overlaps with periodic OMEs. Additionally, the predictability limit of periodic OME tracks is about 49 days for both CEs and AEs, which is 5-10 days higher than the mean values. Usually, in the SCS, OMEs characterized by high predictability limit values exhibit more extended and smoother trajectories and often move along the northern slope of the SCS.

关键词： predictability mesoscale eddy nonlinear local Lyapunov exponent South China Sea seasonal variability

O(logN) Algorithm for Amplitude Amplification and O(logN) Algorithms for Amplitude Transfer in Grover’s Algorithm

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American Journal of Computational Mathematics 2024年第2期14卷 169-188页

作者： Ying liu Department of Engineering Technology Savannah State University Savannah Georgia USA

Grovers algorithm is a category of quantum algorithms that can be applied to many problems through the exploitation of quantum parallelism. The Amplitude Amplification in Grovers algorithm is T = O(N). This paper introduces two new algorithms for Amplitude Amplification in Grovers algorithm with a time complexity of T = O(logN), aiming to improve efficiency in quantum computing. The difference between Grovers algorithm and our first algorithm is that the Amplitude Amplification ratio in Grovers algorithm is an arithmetic series and ours, a geometric one. Because our Amplitude Amplification ratios converge much faster, the time complexity is improved significantly. In our second algorithm, we introduced a new concept, Amplitude Transfer where the marked state is transferred to a new set of qubits such that the new qubit state is an eigenstate of measurable variables. When the new qubit quantum state is measured, with high probability, the correct solution will be obtained.

关键词： Quantum Computing Oracle Amplitude Amplification Grover’s Algorithm

Defects evolution in n-type 4H-SiC induced by electron irradiation and annealing

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Journal of Semiconductors 2024年第7期45卷 77-83页

作者： Huifan Xiong Xuesong Lu Xu Gao Yuchao Yan Shuai liu Lihui Song Deren Yang Xiaodong Pi State Key Laboratory of Silicon and Advanced Semiconductor Materials&School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027China Key Laboratory of Power Semiconductor Materials and Devices of Zhejiang Province&Institute of Advanced Semiconductors ZJU-Hangzhou Global Scientific and Technological Innovation CenterZhejiang UniversityHangzhou 311200China

Radiation damage produced in 4H-SiC by electrons of different doses is presented by using multiple characterization techniques. Raman spectra results indicate that SiC crystal structures are essentially impervious to 10 Me V electron irradiation with doses up to 3000 kGy. However, irradiation indeed leads to the generation of various defects, which are evaluated through photoluminescence(PL) and deep level transient spectroscopy(DLTS). The PL spectra feature a prominent broad band centered at 500 nm, accompanied by several smaller peaks ranging from 660 to 808 nm. The intensity of each PL peak demonstrates a linear correlation with the irradiation dose, indicating a proportional increase in defect concentration during irradiation. The DLTS spectra reveal several thermally unstable and stable defects that exhibit similarities at low irradiation ***, after irradiating at the higher dose of 1000 kGy, a new stable defect labeled as R_(2)(Ec-0.51 eV) appeared after annealing at 800 K. Furthermore, the impact of irradiation-induced defects on SiC junction barrier Schottky diodes is discussed. It is observed that high-dose electron irradiation converts SiC n-epilayers to semi-insulating layers. However, subjecting the samples to a temperature of only 800 K results in a significant reduction in resistance due to the annealing out of unstable defects.

关键词： 4H-SiC deep level transient spectroscopy(DLTS) photoluminescence(PL) defects

NextPolish2:A Repeat-aware Polishing Tool for Genomes Assembled Using HiFi Long Reads

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Genomics, Proteomics & Bioinformatics 2024年第1期22卷 105-109页

作者： Jiang Hu Zhuo Wang Fan Liang Shan-Lin liu Kai Ye De-Peng Wang School of Automation Science and Engineering Faculty of Electronic and Information EngineeringXi’an Jiaotong UniversityXi’an 710049China GrandOmics Biosciences Beijing 102206China Department of Entomology College of Plant ProtectionChina Agricultural UniversityBeijing 100193China

The high-fidelity(HiFi)long-read sequencing technology developed by PacBio has greatly improved the base-level accuracy of genome ***,these assemblies still contain base-level errors,particularly within the error-prone regions of HiFi long *** genome polishing tools usually introduce overcorrections and haplotype switch errors when correcting errors in genomes assembled from HiFi long ***,we describe an upgraded genome polishing tool-NextPolish2,which can fix base errors remaining in those“highly accurate”genomes assembled from HiFi long reads without introducing excessive overcorrections and haplotype switch *** believe that NextPolish2 has a great significance to further improve the accuracy of telomere-to-telomere(T2T)***2 is freely available at https://***/Nextomics/NextPolish2.

关键词： Telomere-to-telomere Genome assembly Genome polishing Error correction HiFi long read

Review of Artificial Intelligence for Oil and Gas Exploration: Convolutional Neural Network Approaches and the U-Net 3D Model

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Open Journal of Geology 2024年第4期14卷 578-593页

作者： Weiyan liu College of Geosciences China University of Petroleum (Beijing) Beijing China

Deep learning, especially through convolutional neural networks (CNN) such as the U-Net 3D model, has revolutionized fault identification from seismic data, representing a significant leap over traditional methods. Our review traces the evolution of CNN, emphasizing the adaptation and capabilities of the U-Net 3D model in automating seismic fault delineation with unprecedented accuracy. We find: 1) The transition from basic neural networks to sophisticated CNN has enabled remarkable advancements in image recognition, which are directly applicable to analyzing seismic data. The U-Net 3D model, with its innovative architecture, exemplifies this progress by providing a method for detailed and accurate fault detection with reduced manual interpretation bias. 2) The U-Net 3D model has demonstrated its superiority over traditional fault identification methods in several key areas: it has enhanced interpretation accuracy, increased operational efficiency, and reduced the subjectivity of manual methods. 3) Despite these achievements, challenges such as the need for effective data preprocessing, acquisition of high-quality annotated datasets, and achieving model generalization across different geological conditions remain. Future research should therefore focus on developing more complex network architectures and innovative training strategies to refine fault identification performance further. Our findings confirm the transformative potential of deep learning, particularly CNN like the U-Net 3D model, in geosciences, advocating for its broader integration to revolutionize geological exploration and seismic analysis.

关键词： Deep Learning Convolutional Neural Networks (CNN) Seismic Fault Identification U-Net 3D Model Geological Exploration

Study of three-dimensional spatial diffuse discharge in contact electrode structure applied to air purification

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Plasma Science and Technology 2024年第10期26卷 73-81页

作者： Shuai XU Wenzheng liu Jiaying QIN Yiwei SUN Xitao JIANG Qi QI School of Electrical Engineering Beijing Jiaotong UniversityBeijing 100044People’s Republic of China

In this work,based on the role of pre-ionization of the non-uniform electric field and its effect of reducing the collisional ionization coefficient,a diffuse dielectric barrier discharge plasma is formed in the open space outside the electrode structure at a lower voltage by constructing a three-dimensional non-uniform spatial electric field using a contact electrode *** air purification study is also carried ***,a contact electrode structure is constructed using a three-dimensional wire *** distribution characteristics of the spatial electric field formed by this electrode structure are analyzed,and the effects of the non-uniform electric field and the different angles of the vertical wire on the generation of three-dimensional spatial diffuse discharge are ***,the copper foam contact electrode structure is constructed using copper foam material,and the effects of different mesh sizes on the electric field distribution are *** results show that as the mesh size of the copper foam becomes larger,a strong electric field region exists not only on the surface of the insulating layer,but also on the surface of the vertical wires inside the copper foam,i.e.,the strong electric field region shows a three-dimensional ***,as the mesh size increases,the area of the vertical strong electric field also ***,the electric field strength on the surface of the insulating layer gradually ***,the appropriate mesh size can effectively increase the discharge area,which is conducive to improving the air purification ***,a highly permeable stacked electrode structure of multilayer wire-copper foam is *** combination with an ozone treatment catalyst,an air purification device is fabricated,and the air purification experiment is carried out.

关键词： dielectric barrier discharge three-dimensional spatial discharge atmospheric pressure air diffusion discharge air purification

Convergent synthesis and immunological study of oligosaccharide derivatives related to galactomannan from Antrodia cinnamomea

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Chinese Chemical Letters 2024年第5期35卷 155-160页

作者： Shuying Li Weiwei ZhuGe Xuan Sun Chongzhen Sun Zhaojun liu Chenghe Xiong Min Xiao Guofeng Gu National Glycoengineering Research Center and Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology Shandong UniversityQingdao 266237China NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate-based Medicine Shandong UniversityQingdao 266237China

The galactomannan from Antrodia cinnamomea(AC)is characterized as one of the important bioactive components that exhibits potential immunostimulatory *** biological function of its corresponding oligosaccharide fragments has not been revealed *** this study,we reported the first chemical synthesis of the series of oligosaccharide fragments related to AC galactomannan via the convergent glycosylation *** preliminary immunological evaluation of these synthesized AC oligosaccharides disclosed that the backbone tetrasaccharide 1d showed the best immunomodulatory ability on enhancing proliferation,phagocytosis and cytokines secretion of Raw264.7 macrophages in vitro,indicating its immense potential as an immunostimulant candidate.

关键词： Antrodia cinnamomea Galactomannan Oligosaccharide Immunostimulatory propriety Chemical synthesis

Enantioselective Synthesis of Benzimidazole Atropisomers Featuring a N-N Axis

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Chinese Journal of Chemistry 2024年第7期42卷 711-718页

作者： Fang-Bei Ge Qi-Kun Yin Chuan-Jun Lu Xuan Xuan Jia Feng Ren-Rong liu College of Chemistry and Chemical Engineering Qingdao UniversityQingdaoShandong 266071China School of Pharmacy Key Laboratory of Molecular Pharmacology and Drug EvaluationMinistry of EducationYantai UniversityYantaiShandong 264005China

Atroposelective synthesis of N-N atropisomers is an emerging area but remains underexplored;in particular,the synthesis of N-N benzimidazole atropisomers is still ***,the first enantioselective synthesis of N-N benzimidazole atropisomers via the palladium-catalyzed de novo construction of benzimidazole skeleton is *** readily available palladium catalyst and biphosphine ligand,a broad range of nonbiaryl benzimidazole and indole-benzimidazole atropisomers were conveniently ac-cessed in high yields and with excellent ***,these N-N benzimidazole atropisomers showed great anti-tumor activity and selectivity to breast cancer MCF-7 *** simple catalytic system,broad substrate scope,high enantioselectivi-ty,and good bioactivity make this approach highly attractive.

关键词： Asymmetric synthesis Atropisomerism Palladium Benzimidazole Antitumor