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Two-dimensional localized modes in nonlinear systems with linear nonlocality and moiré lattices

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Frontiers of physics 2024年第4期19卷 265-273页

作者： Xiuye liu Jianhua zeng Center for Attosecond Science and Technology State Key Laboratory of Transient Optics and PhotonicsXi’an Institute of Optics and Precision Mechanics of Chinese Academy of SciencesXi’an 710119China University of Chinese Academy of Sciences Beijing 100049China Collaborative lnnovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

Periodic structures structured as photonic crystals and optical lattices are fascinating for nonlinear waves engineering in the optics and ultracold atoms ***éphotonic and optical lattices—two-dimensional twisted patterns lie somewhere in between perfect periodic structures and aperiodic ones—are a new emerging investigative tool for studying nonlinear localized waves of diverse ***,a theory of two-dimensional spatial localization in nonlinear periodic systems with fractional-order diffraction(linear nonlocality)and moiréoptical lattices is ***,the flat-band feature is well preserved in shallow moiréoptical lattices which,interact with the defocusing nonlinearity of the media,can support fundamental gap solitons,bound states composed of several fundamental solitons,and topological states(gap vortices)with vortex charge s=1 and 2,all populated inside the finite gaps of the linear Bloch-wave *** the linear-stability analysis and direct perturbed simulations,the stability and instability properties of all the localized gap modes are surveyed,highlighting a wide stability region within the first gap and a limited one(to the central part)for the third *** findings enable insightful studies of highly localized gap modes in linear nonlocality(fractional)physical systems with shallow moirépatterns that exhibit extremely flat bands.

关键词： moiréoptical lattices gap solitons and vortices ultracold atoms Gross-Pitaevskii/nonlinear fractional Schrödinger equation nonlinear fractional systems

Barite in omphacite-hosted K-feldspar + quartz poly-crystalline aggregates from the Sulu eclogites and its implications

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Chinese Science Bulletin 2007年第21期52卷 2995-3001页

作者： zeng LingSen liu FuLai LIANG FengHua CHEN FangYuan Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

K-feldspar + quartz polycrystalline aggregates were found as sub-millimeter-size inclusions with a pseudomorph after coesite (?) in omphacites from a number of Sulu eclogites. In these aggregates, round or subhedral barites occur as tiny inclusions in either K-feldspar or quartz. Energy dispersive spectroscopy (EDS) analyses show that these barites have (1) 33.86%―41.12% SO3, 0%―34.65% SrO, and 24.12%―63.55% BaO, (2) seemingly negative linear correlations between SrO and BaO, indicating that they are ideal solid solutions of barite (BaSO4) and celestite (SrSO4), and (3) highly variable Sr/Ba molar ratios ranging from 0 to 2.1. Presence of barites in the Sulu eclogites not only indicates oxidation of the subducting continental crust, but also very limited and restricted fluids pre- sented during exhumation of the Sulu UHP eclogites.

关键词：重晶石集料变质作用石英石

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

Mesoscale simulation of discontinuous dynamic recrystallization using the cellular automaton method

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Acta Metallurgica Sinica(English Letters) 2011年第4期24卷 287-294页

作者： Baojun YU Xiaojun GUAN Lijun WANG Qingkai zeng Qianqian liu Yu CAO Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) School of Materials Science and Engineering Shandong University Jinan 250061 China

A dynamic recrystallization （DRX） cellular automaton （CA） model that can mark the microstructure with DRX circle was developed. The effects of initial grain size on the stress-strain curve, mean grain size and DRX fraction were mainly investigated, and the simulated results were compared with those obtained from previous researches. The results show that the shape of the stress-strain curve is sensitive, while the stress and mean grain size at the steady state are insensitive to the initial grain size. The transition from a multiple-peak stress-strain curve to a single-peak one can be explained by variations in DRX circle fraction, and the initial grain size to make this transition is between 70 and 80 tim.

关键词： Dynamic recrystallization Cellular automaton DRX circle Copper

Mass spectrometry-based proteomic approaches to study pathogenic bacteria-host interactions

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Protein & Cell 2015年第4期6卷 265-274页

作者： Yufei Yang Mo Hu Kaiwen Yu Xiangmei zeng Xiaoyun liu Institute of Analytical Chemistry and Synthetic and Functional Biomolecules Center College of Chemistry and MolecularEnclineerinq Pekinq University Beijing 100871 China

Elucidation of molecular mechanisms underlying host- pathogen interactions is important for control and treatment of infectious diseases worldwide. Within the last decade, mass spectrometry （MS）-based proteomics has become a powerful and effective approach to better understand complex and dynamic host-pathogen inter- actions at the protein level. Herein we will review the recent progress in proteomic analyses towards bacterial infection of their mammalian host with a particular focus on enteric pathogens. Large-scale studies of dynamic proteomic alterations during infection will be discussed from the perspective of both pathogenic bacteria and host cells.

关键词： mass spectrometry proteomics bacterial infection host-pathogen interactions

Optimal power and subcarrier allocation with partial side information for downlink OFDMA system

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The Journal of China Universities of Posts and Telecommunications 2010年第5期17卷 50-57页

作者： zeng Ling-kang liu Yuan-an XIE Gang CHANG Ling-jun Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

In this paper,we investigate the power and subcarrier allocation issue in the case of partial side information for downlink orthogonal frequency division multiple access （OFDMA） *** method is utilized to characterize the necessary conditions of the optimal solution and the uniqueness of the optimal solution is *** game theoretical concept,surplus function is also introduced to analyze the optimal *** on the theoretical analysis,we propose iterative surplus balancing algorithm （ISBA） that can jointly assign the power and subcarriers in multiple rounds,and then the optimality of ISBA is *** results are presented to show the characteristics of the theoretical analysis and ISBA.

关键词： resource allocation partial side information OFDMA surplus function game theory

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方解石热释光定年技术的发展历史与展望

地震地质 2024年第3期46卷 699-722页

作者：秦可心胡贵明刘静沈续文高云鹏王文鑫温欣语蒋帅宇天津大学地球系统科学学院表层地球系统科学研究院天津300072 中国地震局地质研究所地震动力学国家重点实验室北京100029

矿物晶体中累积的释光信号与其暴露在辐射环境中的时间相关,可用于测定沉积物年代。近年来,依托石英和长石2种矿物释光信号的测年方法日臻成熟,但这2种矿物的释光信号过早饱和,限制了其测年上限(通常<300ka)。前人研究表明,方解石亦有... 详细信息

矿物晶体中累积的释光信号与其暴露在辐射环境中的时间相关,可用于测定沉积物年代。近年来,依托石英和长石2种矿物释光信号的测年方法日臻成熟,但这2种矿物的释光信号过早饱和,限制了其测年上限(通常<300ka)。前人研究表明,方解石亦有可能成为热释光测年材料,因为其热释光信号对剂量响应的灵敏度高,且特征饱和剂量约可达3000~5000Gy,有望将释光测年范围扩展至第四纪尺度。特别地,这一技术的发展也将拓展目前仅限于剥露速率极高地区的释光低温热年代学的应用范围,使其更好地贡献于地貌演化和构造活动的研究。文中对方解石热释光的基本原理和测年流程进行了简要概括,总结了方解石热释光测年应用及动力学参数的研究成果。此外,利用方解石热释光技术对虎跳峡段的基岩样品进行了测试,结果表明,ITL-235℃释光信号可用于该地区剥露历史的恢复工作。同时,文中基于上述内容讨论了方解石热释光技术的应用潜力和待解决问题,以期为该技术在构造地貌领域的应用提供帮助。

关键词：方解石热释光低温热年代学虎跳峡

百香果响应烟草疫霉侵染的分子机制及基因挖掘

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南方农业学报 2024年第3期55卷 589-600页

作者：孙嘉曼陈格罗海玲黄永才刘增亮杨柳张进忠嘉应学院/广东省山区特色农业资源保护与精准利用重点实验室广东梅州514015 农业农村部百香果生物学与遗传育种重点实验室广西南宁530007 广西农业科学院/广西作物遗传改良生物技术重点开放实验室广西南宁530007 广西农业科学院微生物研究所广西南宁530007

【目的】在转录水平上分析百香果响应烟草疫霉(Phytophthora nicotianae)侵染的表达模式,挖掘抗性相关基因并解析其作用机制,为利用分子手段进行百香果抗病性状筛选和抗病品种选育打下基础。【方法】以百香果主栽品种钦果9号为试材,对... 详细信息

【目的】在转录水平上分析百香果响应烟草疫霉(Phytophthora nicotianae)侵染的表达模式,挖掘抗性相关基因并解析其作用机制,为利用分子手段进行百香果抗病性状筛选和抗病品种选育打下基础。【方法】以百香果主栽品种钦果9号为试材,对烟草疫霉侵染12、24、48、72和96 hpi钦果9号进行组织表型观察和生理指标测定;采用转录组测序(RNA-Seq)构建钦果9号响应烟草疫霉侵染的转录组,使用DESeq分析基因表达差异,以P<0.005、错误发现率(FDR)≤0.001和|log2 Ratio|≥1为标准筛选差异表达基因(DEGs);通过BLAST2GO和KOBAS2等进行DEGs的GO功能注释分析和KEGG信号通路富集分析,明确钦果9号响应烟草疫霉侵染的主要通路和代谢途径;挖掘与植物抗病相关代谢通路的DEGs并利用MeV软件绘制基因表达热图,分析其在烟草疫霉侵染钦果9号过程中的动态变化趋势;实时荧光定量PCR验证基因表达量差异与转录组数据的一致性。【结果】烟草疫霉侵染钦果9号初期叶片无明显症状,侵染48hpi叶片出现褪绿,随着侵染时间不断延长,病斑颜色变深并不断扩大呈明显棕色枯斑;从侵染12hpi开始所有处理组钦果9号叶片中时超氧化物歧化酶(SOD)活性显著高于对照组(P<0.05),在24 hpi时SOD活性达最高值,表明侵染初期烟草疫霉已开始从伤口侵入钦果9号叶片。转录组分析共筛选获得7163个DEGs,KEGG信号通路富集分析发现,DEGs主要在植物激素信号转导、植物—病原菌互作、苯丙烷类生物合成、MAPK信号途径及类黄酮生物合成等与植物抗病相关的通路显著富集,表明这些通路在转录水平上是百香果响应烟草疫霉侵染的主要代谢途径。植物—病原菌互作通路中的PR1、CERK1、RPM1、CDPK和CML等基因,茉莉酸(JA)/乙烯(ET)信号途径中的JAR1、JAZ2、ERF1、EBF1和ERS等基因,以及次生代谢相关的CAD6、4CL、POD、CHS和LDOX等基因均在感染烟草疫霉的钦果9号植株中大幅上调表达,推测这些基因参与了百香果对烟草疫霉的抗性反应过程。实时荧光定量PCR结果验证了RNA-Seq数据的可靠性。【结论】植物激素信号转导、植物—病原菌互作、苯丙烷类生物合成、MAPK信号途径及类黄酮生物合成是百香果响应烟草疫霉侵染的主要信号通路和代谢途径。不同代谢途径中的关键基因以复杂方式参与了百香果对烟草疫霉的抗性反应过程。

关键词：百香果烟草疫霉转录组分析分子机制基因挖掘

Effect of structural parameters on the setting performance of plug slips during hydraulic fracturing

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Petroleum Science 2022年第2期19卷 731-742页

作者： Chao Zheng zeng-Kai liu Xin-Lei Wu Aibaibu Abulimiti Jie Qin Xue-Fei Zheng Yong-Hong liu Department of Chemical and Process Engineering University of SurreyGuildfordGU27XHUnited Kingdom College of Mechanical and Electronic Engineering China University of PetroleumQingdao266580China

Slip is one of the most critical components for the frac plug,which would lodge into the casing and lock the frac plug in place during the setting and anchoring ***,fracture failure of slip significantly affects the hydraulic fracturing effects and has attracted tremendous *** this paper,a three-dimensional contact model is applied to explore the setting process of *** effects of key structural parameters such as apex angle,inclination angle,and wedge angle on the contact characteristics of slip are systematically *** results indicate that the maximum contact stress appears at the contact area between slip tooth and the casing’s inner ***,the maximum contact stress generally increases with the increase of apex angle and inclination angle,while decrease linearly with the rise in the wedge *** results show that the slip teeth get blunt and appear severe plastic deformation,which arises from stress *** of biting area indicates that the experimental results are about 21.3%larger,which still have a reasonable agreement with the numerical *** obtained results can guide the parametric selection of plug slip and other similar components.

关键词： Hydraulic fracturing Plug slips Setting performance Fracture failure