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Chinese Physics Letters 2018年第11期35卷 23-27页

作者： Wen-Jing Cheng shi-hua zhao School of Electrical & Electronic Information Shangqiu Normal University

We extend the third perturbation theory to study the polarization control behavior of the intermediate state absorption in Nd^（3＋）ions. The results show that coherent interference can occur between the single-photon and three-photon excitation pathways, and depends on the central frequency of the femtosecond laser field. Moreover,single-photon and three-photon absorptions have different polarization control efficiencies, and the relative weight of three-photon absorption in the whole excitation processes can increase with increasing the laser ***, the enhancement or suppression of the intermediate state absorption can be realized and manipulated by properly designing the intensity and central frequency of the polarization modulated femtosecond laser *** research can not only enrich theoretical research methods for the up-conversion luminescence manipulation of rare-earth ions, but also can provide a clear physical picture for understanding and controlling multi-photon absorption in a multiple energy level system.

关键词： ab Simulation of Intermediate State Absorption Enhancement in Rare-Earth Ions by Polarization Modulated Femtosecond Laser Field

λ/20-Thick cavity for mimicking electromagnetically induced transparency at telecommunication wavelengths

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Advanced Photonics 2024年第3期6卷 42-50页

作者： hua Lu Shouhao shi Dikun Li Shuwen Bo Jianxu zhao Dong Mao Jianlin zhao Northwestern Polytechnical University School of Physical Science and TechnologyMOE Key Laboratory of Material Physics and Chemistry under Extraordinary ConditionsKey Laboratory of Light-Field Manipulation and Information AcquisitionMinistry of Industry and Information TechnologyShaanxi Key Laboratory of Optical Information TechnologyXi’anChina

Optical cavities play crucial roles in enhanced light-matter interaction,light control,and optical communications,but their dimensions are limited by the material property and operating *** planar cavities are urgently in demand for large-area and integrated optical ***,extremely reducing the planar cavity dimension is a critical challenge,especially at telecommunication ***,we demonstrate a type of ultrathin cavities based on large-area grown Bi_(2)Te_(3)topological insulator(TI)nanofilms,which present distinct optical resonance in the near-infrared *** result shows that the Bi_(2)Te_(3)TI material presents ultrahigh refractive indices of>6 at telecommunication *** cavity thickness can approach 1/20 of the resonance wavelength,superior to those of planar cavities based on conventional Si and Ge high refractive index ***,we observed an analog of the electromagnetically induced transparency(EIT)effect at telecommunication wavelengths by depositing the cavity on a photonic *** EIT-like behavior is derived from the destructive interference coupling between the nanocavity resonance and Tamm *** spectral response depends on the nanocavity thickness,whose adjustment enables the generation of obvious Fano *** experiments agree well with the *** work will open a new door for ultrathin cavities and applications of TI materials in light control and devices.

关键词： topological insulator optical nanocavity photonic crystal electromagnetically induced transparency-like effect

Up-conversion luminescence tuning in Er^3+ -doped ceramic glass by femtosecond laser pulse at different laser powers

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Chinese Physics B 2018年第12期27卷 224-230页

作者： Wen-Jing Cheng Guo Liang Ping Wu shi-hua zhao Tian-Qing Jia Zhen-Rong Sun Sift-An Zhang School of Electronic &Electrical Engineering Shangqiu Normal UniversityShangqiu 476000China State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200062China

The up-conversion luminescence tuning of rare-earth ions is an important research topic for understanding luminescence mechanisms and promoting related applications. In this paper, we experimentally study the up-conversion luminescence tuning of Er3+-doped ceramic glass excited by the unshaped, V-shaped and cosine-shaped femtosecond laser field with different laser powers. The results show that green and red up-conversion luminescence can be effectively tuned by varying the power or spectral phase of the femtosecond laser field. We further analyze the up-conversion luminescence tuning mechanism by considering different excitation processes, including single-photon absorption(SPA), two-photon absorption(TPA), excited state absorption(ESA), and energy transfer up-conversion(ETU). The relative weight of TPA in the whole excitation process can increase with the increase of the laser power, thereby enhancing the intensity ratio between green and red luminescence(I547/I656). However, the second ETU(ETU2) process can generate red luminescence and reduce the green and red luminescence intensity ratio I547/I656, while the third ESA(ESA3) process can produce green luminescence and enhance its control efficiency. Moreover, the up-conversion luminescence tuning mechanism is further validated by observing the up-conversion luminescence intensity, depending on the laser power and the down-conversion luminescence spectrum under the excitation of 400-nm femtosecond laser pulse. These studies can present a clear physical picture that enables us to understand the up-conversion luminescence tuning mechanism in rare-earth ions, and can also provide an opportunity to tune up-conversion luminescence to promote its related applications.

关键词： rare-earth ions up-conversion luminescence pulse shaping two-photon absorption

Long-wave infrared emission properties of strain-balanced InAs/In_(x)Ga_(1-x)As_(y)Sb_(1-y)type-Ⅱsuperlattice on different substrates

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Rare Metals 2024年第7期43卷 3194-3204页

作者： Chao shi Xuan Fang Hong-Bin zhao Deng-Kui Wang Xi Chen Dan Fang Dong-Bo Wang Xiao-hua Wang Jin-hua Li State Key Laboratory of High Power Semiconductor Lasers School of PhysicsChangchun University of Science and TechnologyChangchun 130022China State Key Laboratory of Advanced Materials for Smart Sensing China General Research Institute for Nonferrous MetalsBeijing 100088China Department of Opto-Electronic Information Science School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China

High-performance type-Ⅱsuperlattices ofⅢ-Ⅴsemiconductor materials play an important role in the development and application of infrared optoelectronic *** the quality of epitaxial materials and clarifying the luminescent mechanism are of great significance for practic al applic *** this work,strain-balanced and high-quality In As/In_(x)Ga_(1-x)As_(y)Sb_(1-y)superlattices without lattice mismatch were achieved on InAs and GaSb substrates *** grown on In As substrate could exhibit higher crystal quality and surface flatness based on high-resolution X-ray diffraction(HRXRD)and atomic force microscopy(AFM)measurements'***,the strain distribution phenomenon from geometric phase analysis indicates that fluctuations of alloy compositions in superlattices on GaSb substrate are more *** addition,the optical properties of superlattices grown on different substrates are discussed *** of the difference in fluctuations of element composition and interface roughness of superlattices on different substrates,the superlattices grown on In As substrate would have higher integral intensity and narrower full-width at half maximum of long-wave infrared ***,the thermal quenching of emission intensity indicates that the superlattices grown on the In As substrate have better recombination ability,which is beneficial for increasing the operating temperature of infrared optoelectronic devices based on this type of superlattices.

关键词： Photoluminescence Alloy compositions fluctuations InAs(Sb)/In_(x)Ga_(1-x)As_(y)Sb_(1-y) Type-Ⅱsuperlattice Substrate

General Mean-Field BDSDEs with Continuous and Stochastic Linear Growth Coefficients

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Journal of Systems Science & Complexity 2024年第5期37卷 1887-1906页

作者： WANG Jinghan shi Yufeng zhao Nana Institute for Financial Studies Shandong UniversityJinan 250100China Zhiyuan School of Liberal Arts Beijing Institute of Petrochemical TechnologyBeijing 102617China

In this paper,the authors study a class of general mean-field BDSDEs whose coefficients satisfy some stochastic ***,the authors prove the existence and uniqueness theorem of solution under stochastic Lipschitz condition and obtain the related comparison ***,the authors further relax the conditions and deduce the existence theorem of solutions under stochastic linear growth and continuous conditions,and the authors also prove the associated comparison ***,an asset pricing problem is discussed,which demonstrates the application of the general meanfield BDSDEs in finance.

关键词： Backward doubly stochastic differential equations comparison theorem mean-field stochastic conditions Wasserstein metric

Study on Catalytic Behavior of Iron-based Catalyst with IITP as Electron Donor in the Polymerization of Butadiene

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Chinese Journal of Polymer Science 2024年第5期42卷 612-619,I0007页

作者： shi-Liang Xu Ying-Nan zhao Yao Yu Qi Yang Li-hua Na Heng Liu Chun-Yu Zhang Xue-Quan Zhang Key Laboratory of Advanced Rubber Material Ministry of EducationSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Shandong Provincial College Laboratory of Rubber Material and Engineering School of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Key Lab of Rubber-Plastics Ministry of Education/Shandong Provincial Key Lab of Rubber-plasticsSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China

In this study,a novel iron-based catalyst system,Fe(acac)3/(isocyanoimino)triptenylphosphorane(IITP)/AlR3,was employed for the synthesis of syndiotactic 1,2-polybutadiene in *** catalyst system exhibits remarkably high catalytic activity,achieving a polymerization activity of 762 kgpolymer·molcatalyst^(-1)·h^(-1)at 50℃with a[BD]/[Fe]molar ratio of ***,living polymerization characteristic were observed during the investigation of the polymerization kinetics of 1,3-butadiene *** characteristics were well demonstrated by a narrow molecular weight distribution(PDI≈2.0)of the resulting polybutadiene and a linear relationship between-ln(1-c)and polymerization time as well as number average molecular weight and polymer *** resultant polymer showed a 1,2-selectivity of approximately 76%and stereoregularity ranging from 62%to 73%(rrrr).Additionally,through kinetic studies on polymerization reaction,an apparent activation energy Ea value of this catalytic system was calculated to be 84.98 kJ·mol^(-1),which suggests that high polymerization temperature favors efficient polymerization.

关键词： Iron catalyst Syndiotactic 1,2-polybutadiene Elastomers Donor Selectivity

Three-dimensional limit variation analysis on the ultimate pullout capacity of the anchor cables based on the Hoek-Brown failure criterion

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Journal of Mountain Science 2024年第3期21卷 1036-1047页

作者： ZUO shi zhao Lianheng HU shihong College of Civil Engineering Changsha UniversityChangsha 410022China Hunan Provincial Key Laboratory for Disaster Prevention and Mitigation of Rail Transit Engineering Structure Key Laboratory of Heavy-Haul Railway Engineering StructureMinistry of EducationCentral South UniversityChangsha 410075China College of Civil Engineering Central South UniversityChangsha 410075China

Only simplified two-dimensional model and a single failure mode are adopted to calculate the ultimate pullout capacity(UPC)of anchor cables in most previous *** study focuses on a more comprehensive combination failure mode that consists of bond failure of an anchorage body and failure of an anchored rock *** three-dimensional ultimate pullout capacity of the anchor cables is calculated based on the Hoek-Brown failure criterion and variation analysis *** numerical solution for the curvilinear function in fracture plane is obtained based on the finite difference theory,which more accurately reflects the failure state of the anchor cable,as opposed to that being assumed in *** results reveal that relying solely on a single failure mode for UPC calculations has limitations,as changes in parameter values not only directly impact the UPC value but also can alter the failure model and thus the calculation method.

关键词： Anchor cable Ultimate pullout capacity(UPC) Failure model Variation analysis Hoek-Brown failure criterion

Left ventricular thrombosis caused cerebral embolism during venoarterial extracorporeal membrane oxygenation support: A case report

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World Journal of Clinical Cases 2024年第5期12卷 973-979页

作者： Yao-Bang Bai Feng zhao Zhen-hua Wu Guo-Ning shi Nan Jiang Intensive Care Unit Department of Cardiac SurgeryTianjin Chest HospitalTianjin 300222China Department of Cardiac Surgery Tianjin Chest HospitalTianjin 300222China

BACKGROUND Venoarterial(VA)extracorporeal membrane oxygenation(ECMO),an effective short-term circulatory support method for refractory cardiogenic shock,is widely ***,retrospective analyses have shown that VA-ECMO-assisted cases were associated with a relatively high mortality rate of approximately 60%.Embolization in important organs caused by complications of left ventricular thrombosis(LVT)during VA-ECMO is also an important *** the incidence of LVT during VA-ECMO is not high,the consequences of embolization are *** SUMMARY A 37-year-old female patient was admitted to hospital because of fever for 4 d and palpitations for 3 *** excluding the diagnosis of coronary heart disease,we established a diagnosis of“clinically explosive myocarditis”.The patient still had unstable hemodynamics after drug treatment supported by VA-ECMO,with heparin for *** day 4 of ECMO support,a left ventricular thro-mbus attached to the papillary muscle root of the mitral valve was found by transthoracic *** ventricular decompression was performed and ECMO was successfully removed,but the patient eventually died of multiple cerebral *** LVT with high mobility during VA-ECMO may cause embolism in important ***,a"wait and see"strategy should be avoided.

关键词： Venoarterial extracorporeal membrane oxygenation Left ventricular thrombosis Cerebral embolism Magnetic Resonance Imaging Therapy Case report

Quaternion-Based Adaptive Trajectory Tracking Control of a Rotor-Missile with Unknown Parameters Identification

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Defence Technology（防务技术） 2024年第1期31卷 375-386页

作者： Jie zhao Zhongjiao shi Yuchen Wang Wei Wang Beijing Institute of Technology Beijing 100081China

This paper investigates the adaptive trajectory tracking control problem and the unknown parameter identification problem of a class of rotor-missiles with parametric system ***,considering the uncertainty of structural and aerodynamic parameters,the six-degree-of-freedom(6Do F) nonlinear equations describing the position and attitude dynamics of the rotor-missile are established,respectively,in the inertial and body-fixed reference ***,a hierarchical adaptive trajectory tracking controller that can guarantee closed-loop stability is proposed according to the cascade characteristics of the 6Do F ***,a memory-augmented update rule of unknown parameters is proposed by integrating all historical data of the regression *** long as the finitely excited condition is satisfied,the precise identification of unknown parameters can be ***,the validity of the proposed trajectory tracking controller and the parameter identification method is proved through Lyapunov stability theory and numerical simulations.

关键词： Rotor-missile Adaptive control Parameter identification Quaternion control

Satellite anomaly detection based on reconstruction discrepancy theory utilizing a new dual-branch reconstruction model

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Science China Technological Sciences 2024年第10期67卷 3294-3307页

作者： zhao HaoTian QIU shi LIU Ming CAO XiBin Research Center of Satellite Technology School of AstronauticsHarbin Institute of Technology

To enhance the accuracy of deep learning methods based on reconstruction discrepancy in satellite anomaly detection tasks, this study proposes a dual-branch reconstruction model(DBRM) and designs a comprehensive satellite anomaly detection framework around this model. Firstly, we introduce the temporal-channel mixer(TC-Mixer) module, which mainly comprises a self-attention layer for capturing long-range temporal dependencies in telemetry data, and two types of feed-forward networks(FFN) for extracting complex patterns in the temporal and channel dimension of telemetry data. This design endows the TC-Mixer module with robust capabilities for extracting complicated dependencies in telemetry data. Secondly, with the TC-Mixer module as the main component, we designed the DBRM. This model utilizes a shared latent representation layer, allowing the regeneration branch and forecasting branch of the DBRM to share most of the feature extraction network architecture. This approach significantly enhances the model's regression accuracy while reducing computational complexity. Thirdly, using the DBRM as the core network model, we devised a comprehensive satellite anomaly detection framework. This includes an anomaly criterion that considers the reconstruction discrepancy of both the regeneration and forecasting branches, the peak-over-threshold(POT) method for anomaly thresholding, and the MIC-based feature engineering method, etc. Finally, we conducted comparative experiments with several SOTA anomaly detection algorithms on two public and one private satellite anomaly detection datasets. The experimental results validate the effectiveness and superiority of our proposed method.

关键词： anomaly detection reconstruction discrepancy dual-branch reconstruction model (DBRM) satellite telemetry data time series