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Transition to Amplitude Death in Coupled System with Small Number of Nonlinear Oscillators

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Communications in Theoretical Physics 2009年第3期51卷 460-464页

作者： chen Hai-ling yang Jun-Zhong School of Science Beijing University of Posts and Telecommunications Beijing 100876 China

In this work, we investigate the amplitude death in coupled system with small number of nonlinear oscillators. We show how the transitions to the partial and the complete amplitude deathes happen. We also show that th... 详细信息

关键词： coupled nonlinear oscillators amplitude death phase synchronization

Hybrid discrete particle swarm optimization algorithm for capacitated vehicle routing problem

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第4期7卷 607-614页

作者： chen Ai-ling yang Gen-ke WU Zhi-ming Department of Automation Shanghai Jiao Tong University Shanghai 200240. China

Capacitated vehicle routing problem (CVRP) is an NP-hard problem. For large-scale problems, it is quite difficult to achieve an optimal solution with traditional optimization methods due to the high computational complexity. A new hybrid ap- proximation algorithm is developed in this work to solve the problem. In the hybrid algorithm, discrete particle swarm optimiza- tion (DPSO) combines global search and local search to search for the optimal results and simulated annealing (SA) uses certain probability to avoid being trapped in a local optimum. The computational study showed that the proposed algorithm is a feasible and effective approach for capacitated vehicle routing problem, especially for large scale problems.

关键词： Capacitated routing problem Discrete particle swarm optimization (DPSO) Simulated annealing (SA)

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高频电刀在重睑成形术中的应用效果

局解手术学杂志 2024年第9期33卷 831-835页

作者：李凌子孙静金君杨辰玲周慧芳蚌埠医科大学研究生院安徽蚌埠233000 上海交通大学医学院附属第九人民医院眼科上海200011

目的比较高频电刀和手术刀在重睑成形术中的应用效果。方法回顾性分析上海交通大学医学院附属第九人民医院2021年1月至7月收治的眼部整形者35例(70眼),随机选取一侧眼为高频电刀组(采用高频电刀行手术),另一侧眼为手术刀组(采用手术刀... 详细信息

目的比较高频电刀和手术刀在重睑成形术中的应用效果。方法回顾性分析上海交通大学医学院附属第九人民医院2021年1月至7月收治的眼部整形者35例(70眼),随机选取一侧眼为高频电刀组(采用高频电刀行手术),另一侧眼为手术刀组(采用手术刀行手术),每组35眼。评估术后双眼重睑成形效果。术后1 d、1周、1个月及3个月观察患者肿胀情况及瘀斑形成情况。术后1周、1个月、3个月采用曼彻斯特瘢痕量表(MSS)评估患者瘢痕情况。将切除的组织行HE染色和TUNEL染色,评估皮肤和肌肉的坏死程度和热损伤范围。结果术后患者双眼在肿胀、瘀斑、疼痛及瘢痕形成方面差异均无统计学意义(P>0.05)。高频电刀组眼睑出现肌肉组织凝固性坏死,手术刀组几乎无凝固性坏死;患者双眼术后凝固性坏死肌肉占比比较差异有统计学意义(P<0.05),高频电刀组热损伤深度大于手术刀组(P<0.05)。结论高频电刀在重睑成形术中操作简单,使用安全,术中切凝及时,可获得良好的手术术野及效果。

关键词：高频电刀肿胀瘢痕瘀斑热损伤凝固性坏死

Synthesis,Crystal Structure and Its Application in Living Cells Imaging of Benz(c)acridine-1,2,3-triazole Derivatives

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Chinese Journal of Structural Chemistry 2021年第10期40卷 1309-1316页

作者： YAN Zhen-Shuo KANG Yan-Hui chen yang-ling HUO Li-Ni Guangxi University of Chinese Medicine Nanning 530001China Hebei University of Engineering Handan 056038China

A highly selective iron ions fluorescent probe based on the benz(c)acridine-1,2,3-triazole derivatives was produced by multi-step reactions. 1-(7-Benz[c]acridinyl)-4-(4-methylphenyl)-1,2,3-triazole(4 a), C_(26)H_(18)N_(4), was structurally determined by single-crystal X-ray diffraction. It crystallizes in the trigonal system, space group R-3 with a = 36.230(10), b = 36.230(10), c = 7.993(3)Å, β = 90°, V = 9086(6)Å^(3), Z = 18, D_(c)= 1.271 g/cm^(3), F(000) = 3636, μ = 0.602 mm^(-1), the final R = 0.0865 and wR = 0.1619 for 3951 observed reflections(I > 2σ(I)). X-ray analysis indicated that all four rings of benz(c)acridine are in the same plane, and the 1,2,3-triazole ring and the corresponding linked benzene(C(1)–C(6)–C(7)–C(8)–C(9)–N(1)) are approximately perpendicular with a dihedral angle of 106.5°. The crystal packing of the compound was stabilized by two weak interactions between C(11)–H(10)…N(4) and C(18)–H(18)…N(1). In fluorescence spectra studies, compound 4 c was exhibited good selectivity and sensitivity towards iron ions in DMSO: mops buffer solution. Furthermore, 4 c was successfully used for imaging iron ions in living He La cervical cancer cells.

关键词： benz(c)acridine-1 2 3-triazole crystal structure fluorescent probe iron ions

A two-step multi-frequency receiver function inversion method for shallow crustal S-wave velocity structure and its application across the basin-mountain range belts in Northeast China

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Science China Earth Sciences 2024年第3期67卷 687-703页

作者： Ruihao yang Xu WANG ling chen Mingye FENG Qifu chen State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

A shallow crustal velocity structure(above 10 km depth) is essential for understanding the crustal structures and deformation and assessing the exploration prospect of natural resources, and also provides priori information for imaging deeper crustal and mantle structure. Passive-source seismic methods are cost-effective and advantageous for regional-scale imaging of shallow crustal structures compared to active-source methods. Among these passive methods, techniques utilizing receiver function waveforms and/or body-wave amplitude ratios have recently gained prominence due to their relatively high spatial resolution. However, in basin regions, reverberations caused by near-surface unconsolidated sedimentary layers often introduce strong non-uniqueness and uncertainty, limiting the applicability of such methods. To address these challenges, we propose a two-step inversion method that uses multi-frequency P-RF waveforms and P-RF horizontal-to-vertical amplitude ratios. Synthetic tests indicate that our two-step inversion method can mitigate the non-uniqueness of the inversion and enhance the stability of the results. Applying this method to teleseismic data from a linear seismic array across the sedimentary basins in Northeast China, we obtain a high-resolution image of the shallow crustal S-wave velocity structure along the array. Our results reveal significant differences between the basins and mountains. The identification of low-velocity anomalies(<2.8 km s^(-1)) at depths less than 1.0 km beneath the Erlian Basin and less than 2.5 km beneath the Songliao Basin suggests the existence of sedimentary layers. Moreover, the high-velocity anomalies(~3.4–3.8 km s^(-1)) occurring at depths greater than 7 km in the Songliao Basin may reflect mafic intrusions emplaced during the Early Cretaceous. Velocity anomaly distribution in our imaging result is consistent with the location of the major faults, uplifts, and sedimentary depressions, as well as active-source seismic res

关键词： Receiver function Frequency dependence Two-step inversion Shallow crustal velocity structures Unconsolidated sedimentary basins

Cross-species transmission and host range genes in poxviruses

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Virologica Sinica 2024年第2期39卷 177-193页

作者： chen-Hui yang A-ling Song Ye Qiu Xing-Yi Ge College of Biology Hunan Provincial Key Laboratory of Medical VirologyHunan UniversityChangsha410012China

The persistent epidemic of human mpox, caused by mpox virus (MPXV), raises concerns about the future spread ofMPXV and other poxviruses. MPXV is a typical zoonotic virus which can infect human and cause smallpox-likesymptoms. MPXV belongs to the Poxviridae family, which has a relatively broad host range from arthropods tovertebrates. Cross-species transmission of poxviruses among different hosts has been frequently reported andresulted in numerous epidemics. Poxviruses have a complex linear double-strand DNA genome that encodeshundreds of proteins. Genes related to the host range of poxvirus are called host range genes (HRGs). This reviewbriefly introduces the taxonomy, phylogeny and hosts of poxviruses, and then comprehensively summarizes thecurrent knowledge about the cross-species transmission of poxviruses. In particular, the HRGs of poxvirus aredescribed and their impacts on viral host range are discussed in depth. We hope that this review will provide acomprehensive perspective about the current progress of researches on cross-species transmission and HRGvariation of poxviruses, serving as a valuable reference for academic studies and disease control in the future.

关键词： Poxvirus Host range gene(HRG) Host spectrum Cross-species transmission

Self-assembly Induced by Complexation of Diblock Copolyelectrolytes and Oppositely Charged Homopolymers

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Chinese Journal of Polymer Science 2024年第9期42卷 1321-1332,I0006页

作者： ling Zhao Zhi-Yuan Yin Jia-Di Jiang Er-Qiang chen Shuang yang Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenter for Soft Mater Science and EngineeringCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China

We investigate the solution self-assembly of a mixture of positively charged homopolymers and AB diblock copolymers,in which the A blocks are negatively charged,and the B blocks are *** electrostatic complexation between oppositely charged polymers drives the formation of many ordered *** microstructures and phase diagrams are calculated using self-consistent field theory(SCFT)based on an ion-pair model with an equilibrium constant K to characterize the strength of binding between positively and negatively charged *** effects of the charge ratio,representing the ratio of charges from the homopolymer over all charges from polymers in the system,on the ordered structure are systematically studied,both for hydrophobic and hydrophilic A *** charge ratio plays an important role in determining the phase boundaries in the phase diagram of salt concentration versus polymer *** also provide information about the varying tendency of the domain spacing and core size of the spherical phase when the charge ratio is changed,and the results are in good agreement with *** studies provide a deep understanding of the self-assembled microstructures of oppositely charged diblock copolymer-homopolymer systems.

关键词： Self-assembly Polyelectrolyte complexation Self-consistent field theory Ion-pair

Enhancement of low-temperature toughness of Fe-Mn-C-Al alloy by rare earth Ce-modified inclusions

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Journal of Iron and Steel Research International 2024年第1期31卷 157-173页

作者： Guang-kai yang Chang-ling Zhuang Yi-zhuang Li chen Hu Shao-bo Li College of Materials and Metallurgy Guizhou UniversityGuiyang550025GuizhouChina Department of Mechanical Engineering University of Hong KongHong Kong999077China The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819LiaoningChina State Key Laboratory of Public Big Data Guizhou UniversityGuiyang550025GuizhouChina

Fe-Mn-C-Al alloys have been recognized as promising materials for certain low-temperature applications due to their exceptional mechanical properties and ***,their limited low-temperature toughness restricts their large-scale applications in specific *** influence of trace amounts of rare earth cerium(Ce)on the low-temperature toughness of Fe-18Mn-0.6C-1.8Al alloys was *** addition of Ce effectively alters the inclu-sions in the alloy,transforming large-sized irregular inclusions into fine ellipsoidal rare earth *** leads to a significant reduction in both the proportion and average size of the inclusions,resulting in their effective dispersion throughout the matrix and improved cryogenic *** presence of Ce-containing inclusions within the matrix reduces stress concentration,thereby inhibiting microcrack formation and improving impact absorption ***-cally,the addition of rare earth Ce alters the fracture behavior of the material at room temperature and low temperature,changing from brittle cleavage fracture to a more ductile failure *** impact toughness of the Fe-Mn-C-Al alloy is significantly improved by the addition of 0.0048 wt.%Ce,particularly at-196℃where the impact toughness reaches 103.6 J/cm^(2),representing an impressive improvement of 87.3%.

关键词： Fe-Mn-C-Al alloy Rare earth Low-temperature toughness Inclusion Fracture

MXene supported PtCo bimetallic catalyst for hydrogen evolution in acidic conditions

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Frontiers in Energy 2024年第3期18卷 369-377页

作者： Guangxun chen Jian-hua ZHANG Kai-ling ZHOU yang yang Haoxiang MA Yuhong JIN Jingbin LIU Hao WANG Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing 100124China Institute of Deep-Sea Science and Engineering Chinese Academy of SciencesSanya 572000China

Using the electrochemical technology to split water molecules to produce hydrogen is the key to obtain green hydrogen for solving the energy crisis. The large-scale application of hydrogen evolution reaction (HER) in water dissociation requires a highly active catalyst. In this paper, the highly dispersed PtCo bimetallic nanoparticles loading on MXene (PtCo/MXene) were prepared by using a step-to-step reduction strategy. The mentioned PtCo/MXene catalyst exhibits a high current density of −100 mA/cm2 in an acidic medium with just a 152 mV overpotential. In addition, the PtCo/MXene catalyst also displays a superior stability. Computational analysis and experimental testing demonstrate that the electronic interaction between Pt and Co can effectively modify the electronic structure of the active site, thereby enhancing the inherent catalytic performance of the material. More importantly, MXene two-dimensional nanosheets can expose more active sites because of their large specific surface area. Furthermore, MXene substrate with excellent electrical conductivity and harmonious interfaces between PtCo and MXene enhance charge transfer efficiency and lower the reaction activation energy.

关键词： MXene PtCo bimetallic hydrogen evolution reaction(HER)