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Effect of Eu^(3+),Bi^(3+),and Li^(+) doping on luminescent property of GdNbO_(4)

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Journal of Rare Earths 2024年第1期42卷 66-75,I0003页

作者： s.W.Wi y.s.lee Department of Physics and Integrative Institute of Basic sciences Soongsil UniversitySeoul06978Republic of Korea

We investigated the emission properties of Eu^(3+)-doped GdNbO_(4)-based oxide phosphors,aiming at improving the Eu^(3+)emission by codoping of Bi^(3+)and Li^(+).Eu^(3+)singly doped,Eu^(3+)and Bi^(3+)doubly doped,and Eu^(3+),Bi^(3+),and Li^(+)triply doped GdNbO_(4)were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu^(3+)in the singly doped samples are significantly improved by the codoping of Bi^(3+),mainly due to the energy transfer from Bi^(3+)to Eu^(3+).The additional codoping of Li^(+)is found to increase the Eu^(3+)emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu^(3+)in GdNbO_(4)does not change significantly with the codoping of Bi^(3+)and Li^(+).Our results indicate that Li^(+)doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO_(4)phosphors.

关键词： Eu^(3+) GdNbO_(4) Codoping of Li^(+) Photoluminescence sensitizer Rare earths

Emissions of Er3+ and yb3+ co-doped srZrO3 nanocrystals under near-infrared and near-ultraviolet excitations

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Journal of Advanced Ceramics 2020年第4期9卷 413-423页

作者： Hyeontae Lim Juyeong Lim soyoung Jang y.s.lee Department of Physics Soongsil UniversitySeoul06978Republic of Korea

In this study,the upconversion(UC)emissions of Er3+and yb3+co-doped srZrO3 nanocrystals(NCs)were investigated in terms of the thermal annealing temperature and concentration of Er3+ions and compared with the emissions under a near-ultraviolet(near-UV)*** NCs were synthesized by the combustion method,and the as-synthesized NCs were post-annealed at high *** X-ray diffraction patterns revealed that the grain sizes and crystallinity degrees of the samples increased with increasing annealing *** photoluminescence spectra of our samples exhibited strong green and very weak red emissions with the near-UV excitation,originating from the f-f transitions in the Er3+***,under near-infrared(near-IR)excitation,we identified sizable visible emissions at 525,547,and 660 nm in our NCs,which indicated that the UC process successfully occurred in our *** UC emissions were maximized in the NCs with an Er3+concentration of 0.02 and thermal annealing at 1000°*** found that the intensity ratios of red to green emissions increased with increasing annealing *** discussed the differences in the emissions between near-UV and near-IR excitations.

关键词： Er3+and yb3+co-doped srZrO3 upconversion downshifting nanocrystals combustion method annealing temperature

The search for the Quantum spin Liquid in Kagome Antiferromagnets

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Chinese Physics Letters 2019年第5期36卷 5-6页

作者： J.-J.Wen y.s.lee stanford Institute for Materials and Energy sciences SLAC National Accelerator Laboratory Department of Applied Physics Stanford University

A quantum spin liquid (QsL) is an exotic quantum ground state that does not break conventional symmetries and where the spins in the system remain dynamic down to zero temperature. Unlike a trivial paramagnetic state,... 详细信息

关键词： The search for the Quantum spin Liquid in Kagome Antiferromagnets Zn

超声引导下神经内注射行经皮化学药物神经阻滞

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国际医学放射学杂志 2008年第5期31卷 415-416页

作者： J.lee y.s.lee 唐光健 Department of Diagnostic Radiology Kyungpook National University Hospital 50 Sam-deok 2 Go Jung Gu Daegu 700-721 South Korea.

对超声引导下神经内化学药物神经阻滞控制顽固性肢体痉挛及其可行性进行了评价。29例有肢体痉挛的病人接受了53次神经内注射化学药物（利多卡因或苯酚）以控制病情。主要阻滞的靶神经为坐骨神经、胫神经与肌皮神经。确定痉挛的肌肉与靶... 详细信息

对超声引导下神经内化学药物神经阻滞控制顽固性肢体痉挛及其可行性进行了评价。29例有肢体痉挛的病人接受了53次神经内注射化学药物（利多卡因或苯酚）以控制病情。主要阻滞的靶神经为坐骨神经、胫神经与肌皮神经。确定痉挛的肌肉与靶神经后，使用25G针在超声引导下行神经内注射。注射利多卡因组平均有效持续时间为（9．1±9．6）d，注射苯酚永久性阻滞组的平均有效持续时间为（164．5±169．4）d。结果表明，超声引导下神经内注射技术是可行、有效的。

关键词：神经阻滞肌痉挛超声检查

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有源钳位准谐振变换器的一种简单驱动电路

电力电子技术 1999年第1期33卷 48-50页

作者：林波涛丘水生 y.s.lee 华南理工大学香港理工大学

提出了有源钳位准谐振变换器的一种新的驱动方式，它无需经过数字电路延时，只需一个电阻和二极管构成的小网络。新的驱动方法简单易用，简化了设计，降低了成本。实验结果表明新方案有效。

关键词：变换器准谐振变换器驱动电路 MOsFET

Ren-integrable and ren-symmetric integrable systems

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Communications in Theoretical Physics 2024年第3期76卷 62-69页

作者： s y Lou school of Physical science and Technology Ningbo UniversityNingbo315211China

A new type of symmetry,ren-symmetry,describing anyon physics and corresponding topological physics,is ***-symmetry is a generalization of super-symmetry which is widely applied in super-symmetric physics such as super-symmetric quantum mechanics,super-symmetric gravity,super-symmetric string theory,super-symmetric integrable systems and so *** and Grassmann numbers are,in some sense,dual conceptions,and it turns out that these conceptions coincide for the ren situation,that is,a similar conception of ren-number(R-number)is devised for *** particular,some basic results of the R-number and ren-symmetry are exposed which allow one to derive,in principle,some new types of integrable systems including ren-integrable models and ren-symmetric integrable *** examples of ren-integrable KdV-type systems and ren-symmetric KdV equations are explicitly given.

关键词： symmetries integrable systems anyon physics extended supersymmetry ren-symmetry

search for production of dark fermion candidates in association with heavy neutral gauge boson decaying to dimuon in proton-proton collisions at√s=8 TeV using CMs open data

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Chinese Physics C 2024年第4期48卷 6-13页

作者： y.Mahmoud H.Abdallah M.T.Hussein s.Elgammal Centre for theoretical physics The British University in EgyptEgypt Physics Department Faculty of ScienceCairo UniversityEgypt

In this study,we conducted a search for dark matter using a part of the data recorded by the CMs experiment during run-I of the LHC in 2012 with a center of mass energy of 8 TeV and an integrated luminosity of 11.6 fb−*** data were gathered from the CMs open *** matter,in the framework of the simplified model(mono-Z′),can be produced from proton-proton collisions in association with a new hypothetical gauge boson,Z′.Thus,the search was conducted in the dimuon plus large missing transverse momentum *** benchmark scenario of mono-Z′,which is known as light vector,was used for interpreting the CMs open *** evidence of dark matter was observed,and exclusion limits were set on the masses of dark matter and Z′at 95%confidence level.

关键词： dark matter large hadron collider CMs open data search for new physics dark fermion

Generalized polynomial chaos expansion by reanalysis using static condensation based on substructuring

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 819-836页

作者： D.lee s.CHANG J.lee Department of Automotive Engineering Hanyang UniversitySeoul 04763Republic of Korea school of Mechanical Engineering Chungnam National UniversityDaejeon 34134Republic of Korea Department of Mechanical Robotics and Energy EngineeringDongguk UniversitySeoul 04620Republic of Korea

This paper presents a new computational method for forward uncertainty quantification(UQ)analyses on large-scale structural systems in the presence of arbitrary and dependent random *** method consists of a generalized polynomial chaos expansion(GPCE)for statistical moment and reliability analyses associated with the stochastic output and a static reanalysis method to generate the input-output data *** the reanalysis,we employ substructuring for a structure to isolate its local regions that vary due to random *** allows for avoiding repeated computations of invariant substructures while generating the input-output data *** substructuring with static condensation further improves the computational efficiency of the reanalysis without losing ***,the GPCE with the static reanalysis method can achieve significant computational saving,thus mitigating the curse of dimensionality to some degree for UQ under high-dimensional *** numerical results obtained from a simple structure indicate that the proposed method for UQ produces accurate solutions more efficiently than the GPCE using full finite element analyses(FEAs).We also demonstrate the efficiency and scalability of the proposed method by executing UQ for a large-scale wing-box structure under ten-dimensional(all-dependent)random inputs.

关键词： forward uncertainty quantification(UQ) generalized polynomial chaos expansion(GPCE) static reanalysis method static condensation substructuring

无症状吸烟者肺纤维化合并肺气肿的患病率及进展:病例对照研究

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国际医学放射学杂志 2015年第5期 503-504页

作者： K.J.Chae G.y.Jin y.M.Han y.s.Kim s.B.Chon y.s.lee 刘仕昌 Department of Radiology Institute of Medical ScienceResearch Institute of Clinical MedicineChonbuk National University Medical School and Hospital

摘要目的评估无症状吸烟者肺纤维化合并肺气肿(CPFE)的患病率,并对其CT随访结果进行研究分析。方法本研究经机构伦理委员会批准。回顾性分析2 016例当前吸烟或既往吸烟者在本医疗保健中心行低剂量胸部CT检查的CT影像。通过CT定量分析评... 详细信息

摘要目的评估无症状吸烟者肺纤维化合并肺气肿(CPFE)的患病率,并对其CT随访结果进行研究分析。方法本研究经机构伦理委员会批准。回顾性分析2 016例当前吸烟或既往吸烟者在本医疗保健中心行低剂量胸部CT检查的CT影像。通过CT定量分析评估肺气肿的程度,2名放射科医师分析肺纤维化的程度。随访CT评价42例肺纤维化的变

关键词：肺纤维化肺气肿肺疾病无症状患病率吸烟者