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Novel intelligent devices: Two-dimensional materials based memristors

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Frontiers of physics 2022年第2期17卷 83-85页

作者： Lena Du Zhongchang Wang guozhong zhao Department of Physics Capital Normal UniversityBeijing 100048China International Iberian Nanotechnology Laboratory(INL)Avenida Mestre JoséVeiga s/n Braga 4715-330Portugal

Two-dimensional(2D)materials with atomic thickness,non-volatile resistive switching feature and compatibility with the semiconducting technology are naturally a good media of memristors.2D materials-based memristors with excellent performance,low-power consumption and high integration density can be integrated with other circuit components to implement the complicate logic computing,which will become a key driving force for the development of artificial intelligence.

关键词： artificial memristor driving

Concurrent multi-scale design optimization of composite frame structures using the Heaviside penalization of discrete material model

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Acta Mechanica Sinica 2016年第3期32卷 430-441页

作者： Jun Yan Zunyi Duan Erik Lund guozhong zhao Dalian University of Technology Dalian 116024 China Aalborg University 9220 Aalborg Denmark

This paper deals with the concurrent multi-scale optimization design of frame structure composed of glass or carbon fiber reinforced polymer laminates. In the composite frame structure, the fiber winding angle at the micro-material scale and the geometrical parameter of components of the frame in the macro-structural scale are introduced as the independent variables on the two geometrical scales. Considering manufacturing requirements, discrete fiber winding angles are specified for the micro design variable. The improved Heaviside penalization discrete material optimization interpolation scheme has been applied to achieve the discrete optimization design of the fiber winding angle. An optimization model based on the minimum structural compliance and the specified fiber material volume constraint has been established. The sensitivity information about the two geometrical scales design variables are also deduced considering the characteristics of discrete fiber winding angles. The optimization results of the fiber winding angle or the macro structural topology on the two single geometrical scales, together with the concurrent two-scale optimization, is separately studied and compared in the paper. Numerical examples in the paper show that the concurrent multi-scale optimization can further explore the coupling effect between the macro-structure and micro-material of the composite to achieve an ultralight design of the composite frame structure. The novel two geometrical scales optimization model provides a new opportunity for the design of composite structure in aerospace and other industries.

关键词： Composite frame structure Multi-scale optimization Topology optimization Fiber winding angle Structural compliance

Research of the terahertz dual-band notch filter based on FSS structures

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Chinese Science Bulletin 2013年第36期58卷 4687-4691页

作者： ZHANG JinLing ZHANG Yu GAO Ke zhao guozhong School of Electronic Engineering Beijing University of Posts and Telecommunications School of Physics Capital Normal University

In this paper,a dual-band notch filter for two-layer frequency selective surface(FSS)at terahertz(THz)frequency with high filtering performance has been realized on high-resistivity silicon *** periodic metallic resonators patterned on the silicon wafer,the designed filter can provide two tunable resonant frequencies for terahertz *** transmission response was improved by introducing an extra surrounding pattern around the T-shaped structure,and the location of transmission drop was tuned independently with geometric *** by finite-integral time-domain method,the filter is designed to operate between 0.2 and 0.6 THz with dual-band band-stop performance,a salient feature of this design is making the low sensitivity of its frequency response to the incident angles,which allows to place the filter close to the radiation source with spherical wave *** proposed structures were fabricated using photolithography and tested by THz time-domain spectroscopy *** results show that the transmission response has more than 12 and 32 dB rejections near 285 and 460 GHz respectively,which is in good agreement with the simulation result.

关键词：陷波滤波器太赫兹波 T形结构双频段 FSS 太赫兹时域光谱频率选择表面谐振频率

OPTIMUM DESIGN AND SENSITIVITY ANALYSIS OF PIEZOELECTRIC TRUSS STRUCTURES

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Acta Mechanica Solida Sinica 2001年第3期14卷 225-234页

作者： zhao guozhong Gu Yuanxian Li Yunpeng Dalian Univ Technol Dept Engn Mech State Key Lab Struct Anal Ind Equipment Dalian 116024 Peoples R China

This paper is concerned with the optimum design and sensitivityanalysis methods of piezo- electric intelligent trusses on thestructural stiffness and free-vibration frequency. On the basis ofthe finite el- ement emthod and taking into account themechanical-electric coupling effect under electric load and me-chanical load, the computational formula of sensitivities ofstructural displacement and free -vibration frequen- cy with respectto the size and shape design variables are proposed.

关键词： piezoelectric intelligent truss mechanical-electric coupling stiffness

Interacting domains of the HN and F Proteins of paramyxovirus

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Chinese Science Bulletin 2005年第22期50卷 2598-2601页

作者： WANG Xiaojia ZHANG guozhong zhao Jixun WANG Ming College of Veterinary Medicine China Agricultural University Beijing 100094 China

Binding sialates to hemagglutinin-neuramini- dase (HN) activates (triggers) the fusion protein (F) to start the membrane fusion process of paramyxovirus, but the mechanism by which the HN and F associate with each other to induce membrane fusion is still unclear. It is noteworthy to study the interaction domains of HN and F of paramyxovirus. To screen interacting domains of the HN and F proteins of Avian parainfluenza virus-2 (APIV-2) and identify the struc- ture of binding proteins, the GST pull-down assay and mass spectroscopy (MS) and circular dichroism (CD) experiments were performed in this study. The study revealed that the globular head region of HN protein tends to form a complex with either the heptad repeat 1 (HR1) or the heptad repeat 2 (HR2) of F protein respectively. This paper discusses the novel fusion mechanism induced by paramyxovirus HN and F proteins.

关键词：副粘病毒蛋白质红血球凝聚素 HN 交感域分色性

THz time-domain spectroscopy of amino acids

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Chinese Science Bulletin 2005年第15期50卷 1561-1565页

作者： WANG Weining YUE Weiwei YAN Haitao ZHANG Cunlin zhao guozhong Department of Physics Capital Normal University. Beijing 100037China

The optical characteristics of four kinds of amino acids (tyrosine, arginine, histidine and glutamine) filled with nitrogen at room temperature were studied by THz time-domain spectroscopy (THz-TDS). Well-resolved absorption and refractive spectrums between 0.1 and 2.8 THz were obtained based on the physical model for extract-ing the optical parameters of materials in THz range. The results not only fill up the spectra gap of amino acids in far-infrared range, supply data for amino acid molecular identification and conformation analysis, but also demon-strate significantly potential to promote the research and application of biological materials in bio-chemical and medical fields by THz-TDS.

关键词：太赫时域光谱学氨基酸指纹光学参数

High efficiency and broad bandwidth terahertz vortex beam generation based on ultra-thin transmission Pancharatnam-Berry metasurfaces

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Chinese Physics B 2021年第5期30卷 667-672页

作者： Wenyu Li guozhong zhao Tianhua Meng Ran Sun Jiaoyan Guo Department of Physics Capital Normal UniversityBeijing Key Laboratory for THz Spectroscopy and ImagingKey Laboratory of THz OptoelectronicsMinistry of EducationBeijing 100048China Institute of Solid State Physics Shanxi Datong UniversityDatong 037009China

The terahertz(THz)vortex beam generators are designed and theoretically investigated based on single-layer ultra-thin transmission *** phase changes of metasurfaces are obtained by utilizing Pancharatnam-Berry phase elements,which possess different rotation angles and are arranged on two concentric rings centered on the *** circularly polarized incident THz beam could be turned into a cross-polarization transmission wave,and the orbital angular momentum(OAM)varies in value by *** l values change from±1 to±5,and the maximal cross-polarization conversion efficiency that could be achieved is 23%,which nearly reaches the theoretical limit of a single-layer *** frequency range of the designed vortex generator is from 1.2 THz to 1.9 THz,and the generated THz vortex beam could keep a high fidelity in the operating *** propagation behavior of the emerged THz vortex beam is analyzed in *** work offers a novel way of designing ultra-thin and single-layer vortex beam generators,which have low process complexity,high conversion efficiency and broad bandwidth.

关键词： metasurface terahertz vortex beam Pancharatnam-Berry phase element conversion efficiency

Mphy gene reveals the involvement of light source in the regulation of pigment metabolism in Monascus ruber

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Food Bioscience 2023年第2期52卷 412-425页

作者： Weidong Li Ailing Li Wanjun Yu Mianhua Chen guozhong zhao Yurong Wang School of Food Science and Engineering Tianjin University of Science&TechnologyTianjin300457China

The growth,development and pigment metabolism of Monascus are regulated by ***,the function of the photoreceptor gene in the Monascus genome has not yet been clearly *** this paper,the gene sequence Mphy,which is homologous to plant phytochrome,was firstly found from Monascus ruber C100 by comparing it with the ***,taking *** C100 as the main research object,by knocking out and overexpressing the Mphy gene,the involvement of Mphy in the regulation of light on the growth and development of Monascus and the metabolism of Monascus pigments(MPs)were preliminarily *** with the original strain C100,the Mphy knockout strain(ΔMphy)and the overexpression strain(OE-Mphy)grew slowly and produced low *** the same time,under different light conditions,red light can promote the growth and sporulation of Monascus,while blue light can inhibit *** are positively regulated by the Mphy gene,that is,the deletion of the Mphy gene reduces the production of MPs,while the overexpression of the gene increases the accumulation of the pigment,especially under red light *** results indicate that the homologous genes of phytochromes are involved in the process of light-regulated growth,development and pigment metabolism in *** on the above results,we found that under red light conditions,Mphy controls the process of pigment metabolism by affecting key enzymes in TCA metabolism and key signaling pathways such as the MAPK signaling pathway.

关键词： Monascus Monascus pigment Phytochrome Growth and development Pigment metabolism

Highly sensitive flexible strain sensor based on the two-dimensional semiconductor tellurium with a negative gauge factor

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Science China(Information Sciences) 2024年第7期67卷 295-304页

作者： Jiarui HE Yusong QU Shengyao CHEN Cong WANG Lena DU Xiaoshan DU Yuanyuan ZHENG guozhong zhao He TIAN College of Mathematics and Physics Beijing University of Chemical Technology School of Integrated Circuits Tsinghua University Beijing China & The Beijing National Research Center for Information Science and Technology (BNRist)Tsinghua University CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology &University of Chinese Academy of Sciences Beijing Key Lab of Terahertz Spectroscopy and Imaging Key Lab of Terahertz OptoelectronicsMinistry of Education Department of Physics Capital Normal University

Research on flexible strain sensors has advanced rapidly in recent years, with particular attention being devoted to two-dimensional(2D) semiconductor materials owing to their exceptional mechanical and electrical properties that are conducive to sophisticated sensing performance. However, resistive strain sensors based on 2D semiconductor materials typically exhibit positive gauge factors(GF), while materials for strain sensors with a negative GF remain elusive. We have identified a trend of reduction in the band gap of the emerging 2D semiconductor material tellurium(Te) under strain in simulations reported in past research,and have observed a negative GF in the Te-based strain sensor. In this study, we combined Te with a flexible polyethylene terephthalate(PET) substrate to manufacture a flexible strain sensor with a significantly negative GF. The results of tests revealed that the Te-based strain sensor achieved an impressive maximum sensitivity of-139.7 within a small range of bending-induced strain(< 1%). Furthermore, it exhibited excellent linearity and good cyclic stability, and was successfully applied to monitor limb movements. The work here verifies the significant potential for the use of Te-based strain sensors in next-generation flexible electronics.

关键词： 2D semiconductor materials 2D tellurium flexible electronics strain sensors negative gauge factor high sensitivity