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Polarization characteristics and controllability mechanism of passive scattering elements

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Journal of Systems Engineering and Electronics 2023年第2期34卷 342-349页

作者： GUO Jie YIN Hongcheng MAN liang LI xin Science and Technology on Electromagnetic Scattering Laboratory Beijing 100854China Beijing Institute of Environmental Features Beijing 100854China

Polarization feature is one of the important features of radar targets,which has been used in many *** this paper,the grid models of some typical foreign moving targets are constructed on the simulation platform,such as glider,cruiser,fixed wing aircraft,and *** electromagnetic scattering characteristics of the moving platforms under the incidence of circular polarization waves are *** typical polarization characteristics which the orthogonal and in-phase components have in the echoes are analyzed and *** on the polarization scattering matrix(PSM)theory,from the point of view of the physical reproduction,the technical status quo that the existing technical approaches are difficult to realize the passive simulation of polarization characteristic of the target is *** solve this problem,combined with the vector synthesis law,the realization mechanism of controllable polarization characteristic of target echoes is proposed,the analytical expressions of polarization control matrix and polarization ratio are deduced,and the controllability of polarization ratio feature in the case of circular polarization is verified by simulation calculation.

关键词： polarization characteristic physical reproduction passive scattering element controllability mechanism radar feature simulation

Monoclinicβ-AgVO_(3) coupled with CdS formed a 1D/1D p-n heterojunction for efficient photocatalytic hydrogen evolution

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Rare Metals 2023年第5期42卷 1494-1507页

作者： Xuan-Pu Wang Zhi-liang Jin xin Li School of Chemistry and Chemical Engineering North Minzu UniversityYinchuan750021China Institute of Biomass Engineering Key Laboratory of Energy Plants Resource and UtilizationMinistry of Agriculture and Rural AffairsSouth China Agricultural UniversityGuangzhou510642China

Improving the separation of photogenerated carriers and suppressing the rapid complication of electron-hole pairs are essential ways to improve photocatalytic hydrogen production *** high recombination rate of the photogenerated carriers is an issue encountered when developing CdS as a promising photocatalytic *** work allowed to accelerate the separation of photogenerated electrons and holes by loading monoclinicβ-AgVO_(3)on hexagonal CdS nanorods to construct a one-dimensional(1D)/1D p-n *** introduction of monoclinicβ-AgVO_(3)with a narrow band gap effectively improves the light absorption of CdS,which is conducive to improving the use of visible *** integrated electric field of the p-n heterojunction can effectively transfer electrons and holes in the direction suitable to hydrogen *** photoluminescence and electrochemical characterization of the catalysts showed that the p-n heterojunction formed after loadingβ-AgVO_(3)greatly improved the separation efficiency of *** hydrogen evolution experiments show that the composite catalyst has good photocatalytic hydrogen evolution capability and *** composite catalyst with the best photocatalytic performance was obtained by studyingβ-AgVO_(3)with different *** composite catalyst reached 581.5μmol of hydrogen amount within 5 h,which is 3.8 times higher than that of CdS alone and its apparent quantum efficiency reaches8.02%.The present work provides a possible solution for the development of perovskite and the extensiveness of CdS in photocatalytic hydrogen evolution.

关键词： Photocatalysis Hydrogen evolution p-n heterojunction AgVO_(3)

Porous hydrogel arrays for hepatoma cell spheroid formation and drug resistance investigation

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Bio-Design and Manufacturing 2021年第4期4卷 842-850页

作者： xin Lei Changmin Shao xin Shou Keqing Shi liang Shi Yuanjin Zhao Translational Medicine Laboratory The First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325035China Wenzhou Institute University of Chinese Academy of SciencesWenzhou 325001China State Key Laboratory of Bioelectronics School of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096China Department of Laboratory Medicine The Eighth Affiliated HospitalSun Yat-Sen UniversityShenzhen 518033China

Drug resistance is one of the major obstacles in the drug therapy of *** in this area in pre-clinical research have focused on developing novel platforms to evaluate and decrease drug *** this paper,inspired by the structure of hives where swarms live and breed,we propose porous hydrogel arrays with a uniform pore structure for the generation of hepatoma cell spheroids and the investigation of drug *** porous hydrogel arrays were fabricated using polyeth-ylene glycol diacrylate(PEGDA)hydrogel to negatively replicate a well-designed *** from the elaborate processing of the template,the prepared porous hydrogel arrays possessed a uniform pore *** to their anti-adhesion properties and the excellent biocompatibility of the PEGDA hydrogel,the hepatoma cells could form well-defined and uni-form hepatoma cell spheroids in the porous hydrogel *** found that the resistant hepatoma cell spheroids showed more significant Lenvatinib resistance and a migratory phenotype compared with a two-dimensional(2D)cell culture,which reveals the reason for the failure of most 2D cell-selected drugs for in vivo *** features give such porous hydrogel arrays promising application prospects in the investigation of tumor cell spheroid culture and in vitro drug resistance.

关键词： Drug resistance Hydrogel Porous Spheroid Hepatoma

Etomidate vs propofol in coronary heart disease patients undergoing major noncardiac surgery:A randomized clinical trial

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World Journal of Clinical Cases 2021年第6期9卷 1293-1303页

作者： Zhong-liang Dai xing-Tao Cai Wen-Li Gao miao Lin Juan Lin Yuan-Xu Jiang xin Jiang Department of Anesthesiology The First Affiliated Hospital of Southern UniversityThe Second Clinical Medical College of Jinan UniversityShenzhen People’s HospitalShenzhen 518020Guangdong ProvinceChina Department of Geriatrics The First Affiliated Hospital of Southern UniversityThe Second Clinical Medical College of Jinan UniversityShenzhen People’s HospitalShenzhen 518020Guangdong ProvinceChina

BACKGROUND The ideal depth of general anesthesia should achieve the required levels of hypnosis,analgesia,and muscle relaxation while minimizing physiologic responses to *** choice of anesthetic strategy in patients with coronary heart disease(CHD)undergoing major noncardiac surgery is becoming an increasingly important issue as the population *** is because general anesthesia is associated with a risk of perioperative cardiac complications and death,and this risk is much higher in people with *** To compare hemodynamic function and cardiovascular event rate between etomidate-and propofol-based anesthesia in patients with *** This prospective study enrolled consecutive patients(American Society of Anesthesiologists grade II/III)with stable CHD(New York Heart Association class I/II)undergoing major noncardiac *** patients were randomly allocated to receive either etomidate/remifentanil-based or propofol/remifentanil-based general *** was performed using a computer-generated random number table and sequentially numbered,opaque,sealed *** was maintained until the patient had arrived in the operating theater,at which point the consulting anesthetist opened the *** patients,data collectors,and data analyzers were blinded to the type of anesthesia *** primary endpoints were the occurrence of cardiovascular events(bradycardia,tachycardia,hypotension,ST-T segment changes,and ventricular premature beats)during anesthesia and cardiac troponin I level at 24 *** secondary endpoints were hemodynamic parameters,bispectral index,and use of vasopressors during *** The final analysis included 40 patients in each of the propofol and etomidate *** incidences of bradycardia,hypotension,ST-T segment changes,and ventricular premature beats during anesthesia were significantly higher in the propofol group than in the etomidate group(P<0.05 for all).The incidence of tachycardia

关键词： Etomidate Propofol General anesthesia Coronary heart disease Hemodynamic Cardiovascular events

Dynamic Analysis of Stochastic Friction Systems Using the Generalized Cell Mapping Method

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Computer Modeling in Engineering & Sciences 2020年第1期122卷 49-59页

作者： Shichao Ma xin Ning liang Wang Northwestern Polytechnical University School of Astronautics Xi’an710072China National Key Laboratory of Aerospace Flight Dynamics Xi’an710072China Northwestern Polytechnical University School of Science Xi’an710129China

Friction systems are a kind of typical non-linear dynamical systems in the actual engineering and often generate abundant dynamics *** of non-smooth characteristics,it is difficult to handle these systems by conventional analysis methods *** the same time,random perturbation often affects friction systems and makes these systems more *** this context,we investigate the steady-state stochastic responses and stochastic P-bifurcation of friction systems under random excitations in this *** in order to retain the non-smooth of friction system,the generalized cell mapping(GCM)method is first used to the original stochastic friction systems without any approximate *** verify the accuracy and validate the applicability of the suggested approach,we present two classical nonlinear friction systems,i.e.,Coulomb force model and Dahl force model as ***,this method is in good agreement with the Monte Carlo simulation method and the computation time is greatly *** addition,further discussion finds that the adjustable parameters can induce the stochastic P-bifurcation in the two examples,*** stochastic P-bifurcation phenomena indicate that the stability of the friction system changes very sensitively with the *** of responses analysis and stochastic P-bifurcation has certain significances for the reliability and stability analysis of practical engineering.

关键词： Friction systems non-smooth stochastic responses cell mapping

Globin-like mesoporous CeO2： A CO-assisted synthesis based on carbonate hydroxide precursors and its applications in low temperature CO oxidation

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Nano Research 2015年第4期8卷 1269-1278页

作者： Yeheng He xin liang Biaohua Chen Chemical Engineering College Beijing University of Chemical Technology Beijing 100029 China

Globin-like mesoporous CeO2 has been constructed by using a CO-assisted synthetic approach based on hydroxide carbonate precursors, in which CO plays a key role in the formation of the globin-like mesoporous precursors as the carbon source because of its preferential adsorption on Ce^3＋ under the hydrothermal conditions. The formation mechanism and the thermal transformation process from globin-like mesoporous CeCO3OH to CeO2 have been investigated by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, BET surface area measurements, thermal analysis, Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy and X-ray photoelectron spec- troscopy. Rod-like building blocks interconnected by nanoparticles circle around to form each globin-like CeO2 spheres, leading to the formation of a mesoporous structure. The globin-like mesoporous CeO2 shows much better performance in CO catalytic oxidation than ordinary CeO2 nanoparticles obtained by directly calcining cerium nitrate. Moreover, the globin-like mesoporous CeO2 can act as an ideal matrix for supported catalysts. Metallic Au particles can be well dispersed in the globin-like CeO2 matrix to form Au/CeO2 supported catalysts, which exhibit excellent activity for CO oxidation at room temperature.

关键词： ceria CO-assisted synthesis mesoporous structure CO catalytic oxidation

Glauber gluon effects in soft collinear factorization

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Communications in Theoretical Physics 2022年第11期74卷 106-135页

作者： Gao-liang Zhou Zheng-xin Yan xin Zhang Feng Li College of Science Xi'an University of Science and TechnologyXi'an 710054China College of Science Nanjing University of Posts and TelecommunicationsNanjing 210023China

Effects of Glauber gluons,which cause the elastic scattering process between different jets,are studied in the frame of soft-collinear effective *** modes are added into the action before being integrated out,which is helpful in studies on the Glauber couplings of collinear and soft *** is proved that the final state interactions cancel out for processes inclusive *** are interactions with the light cone coordinates x^(+)and x^(-)greater than those of the hard *** eikonalization of Glauber couplings of active particles and absorption of these couplings into soft and collinear Wilson lines are discussed,which is related to the loop level definitions of Glauber gluons *** active-spectator coherence is proved to be harmless to the inclusive summation of spectator-spectator and spectator-soft Glauber *** on this result,spectator-spectator and spectator-soft Glauber exchanges cancel out in the processes considered *** aspects of the cancellation are also discussed to explain relations between the graphic and operator level cancellation of Glauber gluons.

关键词： soft-collinear effective theory QCD factorization Glauber gluons

Observational appearances of hairy black holes in the framework of gravitational decoupling

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Communications in Theoretical Physics 2024年第8期76卷 103-117页

作者： Yizhi liang xin Lyu Jun Tao Center for Theoretical Physics College of PhysicsSichuan UniversityChengdu 610065China

We investigate the observational appearance of static and spherically symmetric hairy black holes in the framework of gravitational decoupling with the weak energy condition(WEC). Two types of thin illumination conditions are studied: spherical accretion and disk accretion. As the hairy parameter increases, the size of the photon sphere and photon rings in both models decreases, and the overall luminosity attenuation becomes more pronounced. In spherical accretion, the luminosity of infalling accretion is significantly lower than that of stationary accretion. In disk accretion the luminosity of the black hole is contributed by direct emission, the lensing ring and the photon ring. Employing four types of astrophysical disk luminosity model,we investigate the appearance of halos and note that their luminosities do not superimpose when the source is on or beyond the innermost stable circular orbit.

关键词： hairy black hole shadow gravitational decoupling accretion disk

Answering range-based reverse kNN and why-not reverse kNN queries

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Frontiers of Computer Science 2020年第1期14卷 233-235页

作者： Zhefan ZHONG xin LIN liang HE Shanghai Key Laboratory of Multidimensional Information Processing East China Normal UniversityShanghai 200062China

1 Introduction Given a dataset D and a point q,a reverse nearest neighbor(RNN)query retrieves all the points p∈D that have q as their nearest *** the RNN problem was first pro-posed in[1],it still has received considerable attention due to its importance in several applications involving decision support,resource allocation,profile-based marketing,etc.

关键词： neighbor kNN nearest