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A multicolor photometric study of the neglected eclipsing binary FT Ursae Majoris

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Research in Astronomy and Astrophysics 2011年第10期11卷 1158-1162页

作者： jin-zhao Yuan Department of Physics Shanxi Normal University Linfen 041004 China

The multicolor photometric observations of the neglected eclipsing binary FT Ursae Majoris （FT UMa） were obtained in 2010. The 2003 version of the Wilson- Devinney code was used to analyze the light curves in the B, V and R bands simultaneously. Based on the spectroscopic mass ratio q = 0.984 published by Pribulla et al., it is found that FT UMa is an evolved contact binary with a contact degree of 15.3%. The low amplitude of light variations, N 0.15 mag, arises mainly from a moderately low inclination angle of i = 62.80° and almost identical components in size rather than the light dilution of a third component, which contributes light of only - 10%.

关键词： stars binaries close -- stars binaries clipsing -- stars individual FTUrsae Majoris

Stability of GOY Model Under Modulation of Periodic External Force

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Communications in Theoretical Physics 2008年第2期49卷 521-524页

作者： zhao Ying-kui CHEN Shi-Gang WANG Guang-Rui Institute of Applied Physics and Computational Mathematics P.O. Box 8009（14） Beijing 100088 China

There is a phase transition between quasi-periodic state and intermittent chaos in GOY model with a critical value δ0. When we add a modulated periodic externa/force to the system, the phase transition can also be found with a critical value δe. Due to coupling between the force and the intrinsic fluctuation of the velocity on shells in GOY model, the stability of the system has been changed, which results in the variation of the critical value. For proper intensity and period of the force, δe is unequal to δ0. The critical value is a nonlinear function of amplitude of the force, and the fluctuation of the velocity can resonate with the external force for certain period Te.

关键词： chaos GOY model phase transition

Surface morphology and electronic structure in stoichiometric superconductor CaKFe_(4)As_(4) robed by scanning tunneling microscopy/spectroscopy

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Science China(Physics,Mechanics & Astronomy) 2021年第12期64卷 144-150页

作者： Xiaodong Yu Zhongxu Wei Zhanyi zhao Tao Xie Chang Liu Ge He Qihong Chen Lei Shan Huiqian Luo Qing Huan Jie Yuan kui jin Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Walther Meissner Institute Bayerische Akademie der WissenschaftenGarching 85748Germany Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education Institutes of Physical Science and Information TechnologyAnhui UniversityHefei 230601China Songshan Lake Materials Laboratory Dongguan 523808China

CaKFe_(4)As_(4) is a new-type superconductor with a relatively high transition temperature of 35 K among stoichiometric iron-based superconductors. Based on scanning tunneling microscopy/spectroscopy, the surface morphology and electronic structure of CaKFe_(4)As_(4) single crystal were systematically investigated. The cleaved CaKFe_(4)As_(4) showed various morphologies, such as atomically resolved 1×1, 1×2, and √2×√2 lattices. By analyzing the geometrical correlations of these morphologies, the 1×1 and 1×2 lattices were identified as the original and reconstructed As layers, respectively, whereas the √2×√2 lattice was distinguished as the reconstructed alkaline-earth-metal or alkali-metal layer. The superconducting energy gap of 7.3 me V and bosonic mode of 12.7 me V were resolved in the scanning tunneling spectra. In addition, the superconducting energy gaps measured on different terminations were identical and consistent with the values obtained by bulk-sensitive techniques, indicating that the electronic structures of CaKFe_(4)As_(4) were insensitive to the surface reconstructions. Our study clarifies the relationships between complex surface reconstructions and surface terminations and preliminarily presents that there is no obvious effect of surface reconstructions on electronic states.

关键词： CaKFe_(4)As_(4) scanning tunneling microscopy surface reconstructions superconductivity

A Visco-hyperelastic Constitutive Model for Rubber Considering the Strain Level and One Case Study in the Sealing Packer

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Acta Mechanica Solida Sinica 2023年第5期36卷 710-723页

作者： Lan jin Demin zhao Jianlin Liu College of Pipeline and Civil Engineering China University of Petroleum(East China)Qingdao 266580China

The rubber cylinder is a key component for maintaining the sealing pressure of the packer,particularly in deep underground *** stress relaxation of materials,as a typical feature of viscoelasticity,has become one of the main factors causing the failure of rubber cylinders in *** the present study,a visco-hyperelastic model for the sealing rubber considering different strain levels is proposed based on the Prony ***,the uniaxial compression stress relaxation experiments are conducted on the sealing rubber under different temperatures and strain levels,and the model parameters are thereby *** a case study,the proposed model is incorporated into the ABAQUS software via the UM AT subroutine,and the finite element simulation of the sealing packer is carried *** results show that the sealing performance of the packer improves with a decrease in temperature or an increase in strain *** is also noted that a large strain level can lead to the protrusion of the shoulder of the rubber cylinder.

关键词： Visco-hyperelastic model Temperature Strain level Rubber cylinder Sealing performance

Fast Decoupled Multi-energy Flow Calculation for Integrated Energy System

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Journal of Modern Power Systems and Clean Energy 2020年第5期8卷 951-960页

作者： Yanbo Chen Junyuan zhao jin Ma School of Electrical and Electronic Engineering North China Electric Power UniversityBeijingChina School of Electrical and Information Engineering University of SydneySydneyAustralia

In recent years,as a promising option to improve the overall efficiency of energy utilization and absorptive capacity of renewable energies,the integrated energy system(IES)has raised great interest in academies and ***-energy flow(MF)calculation,which differs from the traditional power flow calculation,plays a basic role in analyzing *** calculation based on Newton-Raphson method has been proposed in literature,but its calculation efficiency is not *** this paper,a fast decoupled MF(FDMF)calculation method for IES is *** main idea is to replace the original Jacobian matrix of MF calculation based on Newton-Raphson method with a diagonal and constant Jacobian matrix by the *** simulations demonstrate that the proposed FDMF method can increase the calculation efficiency by at least 4 times with high calculation accuracy.

关键词： Integrated energy system(IES) multi-energy flow(MF) fast decoupled solution methodology combined electricity-heat-natural gas system flow calculation

Potential role and therapeutic implications of glutathione peroxidase 4 in the treatment of Alzheimer's disease

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Neural Regeneration Research 2025年第3期20卷 613-631页

作者： Yanxin Shen Guimei Zhang Chunxiao Wei Panpan zhao Yongchun Wang Mingxi Li Li Sun Department of Neurology and Neuroscience Center The First Hospital of Jilin UniversityJilin UniversityChangchunJilin ProvinceChina Cognitive Impairment Center Department of NeurologyThe First Hospital of Jilin UniversityJilin UniversityChangchunJilin ProvinceChina

Alzheimer's disease is an age-related neurodegenerative disorder with a complex and incompletely understood pathogenesis. Despite extensive research, a cure for Alzheimer's disease has not yet been found. Oxidative stress mediates excessive oxidative responses, and its involvement in Alzheimer's disease pathogenesis as a primary or secondary pathological event is widely accepted. As a member of the selenium-containing antioxidant enzyme family, glutathione peroxidase 4 reduces esterified phospholipid hydroperoxides to maintain cellular redox homeostasis. With the discovery of ferroptosis, the central role of glutathione peroxidase 4 in anti-lipid peroxidation in several diseases, including Alzheimer's disease, has received widespread attention. Increasing evidence suggests that glutathione peroxidase 4 expression is inhibited in the Alzheimer's disease brain, resulting in oxidative stress, inflammation, ferroptosis, and apoptosis, which are closely associated with pathological damage in Alzheimer's disease. Several therapeutic approaches, such as small molecule drugs, natural plant products, and non-pharmacological treatments, ameliorate pathological damage and cognitive function in Alzheimer's disease by promoting glutathione peroxidase 4 expression and enhancing glutathione peroxidase 4 activity. Therefore, glutathione peroxidase 4 upregulation may be a promising strategy for the treatment of Alzheimer's disease. This review provides an overview of the gene structure, biological functions, and regulatory mechanisms of glutathione peroxidase 4, a discussion on the important role of glutathione peroxidase 4 in pathological events closely related to Alzheimer's disease, and a summary of the advances in small-molecule drugs, natural plant products, and non-pharmacological therapies targeting glutathione peroxidase 4 for the treatment of Alzheimer's disease. Most prior studies on this subject used animal models, and relevant clinical studies are lacking. Future clinica

关键词： apoptosis ferroptosis inflammation lipid peroxidation natural plant products neurodegenerative disorder neuroprotection oxidative stress small-molecule drugs

Multi-port cavity model and low-level RF systems design for VHF gun

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Nuclear Science and Techniques 2020年第1期31卷 80-87页

作者： kui Liu Lin Li Cheng Wang Qiang Gu Ming-Hua zhao Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China

Very high frequency(VHF) photocathode guns have excellent performance and are being increasingly selected as electron sources for high-repetition-rate X-ray free-electron lasers. As a highly loaded quality factor cavity, the VHF gun requires high stability in the amplitude and phase of the cavity field. However, the gun is microwave powered by two solid-state power sources through two separate power couplers. The input difference between the two power couplers will influence the stability of the cavity field. To systematically study this influence and obtain measurement formulae, a multi-port VHF gun LCR circuit model is built and analyzed. During the warm-up condition, the cavity structure will be deformed due to the large-scale change in the cavity temperature. Then, the deformation will result in cavity resonant frequency changes. To prevent the mechanic tuner from suffering damages due to the frequent and long-distance movement for correcting the cavity resonant frequency, a self-excited loop(SEL) control system is considered for changing the loop phase and make the loop frequency follow the resonant frequency. In this study, a steady-state model of the VHF gun cavity is built for obtaining the optimal input coupler coefficient and the stability requirement of the forward voltage. Then, the generator-driven resonator and SEL control system, which combine with the VHF multiport modeling, are modeled and simulated. The simulated results show that the SEL system can perfectly operate in the process of condition and warm-up.

关键词： VHF photocathode gun Multi-port modeling Self-excited loop LLRF control

Prognostic value of body mass index before treatment for laryngeal squamous cell carcinoma

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Cancer Biology & Medicine 2015年第4期12卷 394-400页

作者： zhao-Qu Li Lan Zou Tian-Run Liu An-kui Yang Sun Yat-sen University Cancer Center State Key Laboratory of Oncology in South China Collaborative Innovation Center of Cancer Medicine Department of Head and Neck Surgery Sun Yat-sen University Cancer Center Department of Otorhinolaryngology Head and Neck Surgery The Sixth Affiliated Hospital of Sun Yat-sen University

Objective: Patients with head and neck cancer often suffer from malnutrition. This study aims to investigate the influence of body mass index(BMI) on the prognosis of laryngeal squamous cell carcinoma(LSCC).Methods: A total of 473 patients with LSCC initially treated at Sun Yat-sen University Cancer Center between January 2005 and July 2009 were retrospectively reviewed. Survival analysis was performed by the Kaplan-Meier method and Cox regression ***: Low BMI before treatment was significantly associated with poor overall survival in patients with LSCC(P<0.001). BMI was an independent prognostic factor for patients with ***: Leanness before treatment was associated with poor prognosis in patients with LSCC. Good nutritional status is favorable to improve survival in patients with LSCC.

关键词： Prognosis nutrition body mass index(BMI) laryngeal squamous cell carcinoma(LSCC)

Bio-inspired Design and Evaluation of Porous Fences for Mitigating Fugitive Dust

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Journal of Bionic Engineering 2020年第2期17卷 370-379页

作者： Li Guo Dongsen zhao Bo zhao jin Li jin Tong Yunhai Ma Zhiyong Chang Key Laboratory of Bionic Engineering(Ministry of Education of China) Jilin UniversityChangchun 130022China College of Biological and Agricultural Engineering Jilin UniversityChangchun 130022China

Fugitive dust has been recognized as an important contributor to air pollution,and artificial porous fence is one of the most effective management strategies to reduce fugitive dust in open *** improve the shelter effects and efficiency of Particulate Matter(PM)reduction of traditional fences,this study proposed five bionic fences and their capability was evaluated through wind tunnel *** results indicated that all of bionic fences presented better efficiency in reducing wind speed and PM concentrations compared with traditional fences,and they were more efficient in capturing *** the bionic fences,the non-woven cloth material with four-leave opening presented the best capability both in wind speed and PM *** proposed bionic fences may be further developed and studied for future application in capturing fine PM and adapting to the wind.

关键词： bio-inspired fence particulate matter wind tunnel tests