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Review on dynamic analysis of road pavements under moving vehicles and plane strain conditions

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Journal of Road Engineering 2024年第1期4卷 54-68页

作者： Edmond v.Muho Niki d.Beskou department of disaster Mitigation for Structures Tongji UniversityShanghai 200092China department of Civil Engineering University of the PeloponnesePatras 26334Greece School of Science and Technology Hellenic Open UniversityPatras 26335Greece

This paper reviews works on the dynamic analysis of flexible and rigid pavements under moving vehicles on the basis of continuum-based plane strain models and linear *** purpose of this review is to provide in-formation about the existing works on the subject,critically discuss them and make suggestions for further *** reviewed papers are presented on the basis of the various models for pavement-vehicle systems and the various methods for dynamically analyzing these *** pavements are modeled by a homogeneous or layered half-plane with isotropic or anisotropic and linear elastic,viscoelastic or poroelastic material *** pavements are modeled by a beam or plate on a homogeneous or layered half-plane with material properties like the ones for flexible *** vehicles are modeled as concentrated or distributed over a finite area loads moving with constant or time dependent *** above pavement-vehicle models are dynamically analyzed by analytical,analytical/numerical or purely numerical methods working in the time or frequency *** examples are presented to illustrate the models and methods of analysis,demonstrate their merits and assess the effects of the various parameters on pavement *** paper closes with con-clusions and suggestions for further research in the *** significance of this research effort has to do with the presentation of the existing literature on the subject in a critical and easy to understand way with the aid of representative examples and the identification of new research areas.

关键词： Flexible pavements Rigid pavements Moving vehicles Plane strain models dynamic analysis

development and testing of a high-power S-band klystron at BINP SB RAS

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Nuclear Science and Techniques 2024年第7期35卷 58-67页

作者： A.Levichev A.Barnyakov S.Samoylov d.Nikiforov v.Ivanov M.Arsentyeva d.Chekmenev O.Pavlov I.Pivovarov Budker Institute of Nuclear Physics Lavrentyeva Av.11NovosibirskRussia630090 Novosibirsk State University Pirogova Str.2NovosibirskRussia630090

This paper details the development and testing of the first working prototype of the S-band high-power klystron,accomplished at the Budker Institute of Nuclear Physics,Siberian Branch,Russian Academy of Sciences(BINP SB RAS).Upon testing,the klystron demonstrated the following parameters:an operating frequency of 2856 MHz and a peak power output of 50 *** paper presents the klystron's design,its constituent units,and pertinent processing procedures,along with discussions on the measurement of its parameters.

关键词： Klystron Linear accelerator Electron beam

迭代重建对于大体型成人的多层螺旋CT中影像质量和辐射剂量的影响

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国际医学放射学杂志 2012年第5期 502-502页

作者： G.S.desai R.N.Uppot A.R.Kambadakone d.v.sahani 唐玉霞 department of Abdominal Imaging and Intervention Massachusetts General HospitalHarvard Medical School55 Fruit StreetWhite 270BostonMA 02114USA

摘要目的比较自适应统计迭代重建(ASiR)和滤波反射重建技术(FBP)用于体质量≥91kg病人时的影像质量和辐射剂量。方法在这项机构审查委员会批准的回顾性研究中,对100例体质量≥91kg[91～181.9kg,平均(107.6±17.4)kg]的成人行单期对比增... 详细信息

摘要目的比较自适应统计迭代重建(ASiR)和滤波反射重建技术(FBP)用于体质量≥91kg病人时的影像质量和辐射剂量。方法在这项机构审查委员会批准的回顾性研究中,对100例体质量≥91kg[91～181.9kg,平均(107.6±17.4)kg]的成人行单期对比增强腹部盆腔CT检查,由2名阅片者双盲进行ASiR和FBP影像质量的主观测量值和辐射剂量分析,影像质量使用主观标准化数值模拟和客观噪声来评估。

关键词：迭代重建 CT 成像质量辐射剂量肥胖

低辐射剂量多层CT自适应统计迭代重建技术(ASIR)诊断尿路结石的研究:辐射剂量可以降低至多少?

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国际医学放射学杂志 2012年第6期 589-589页

作者： N.M.Kulkarni R.N.Uppot B.H.Eisner d.v.sahani 史佳培 departments of Abdominal Imaging and Intervention Massachusetts General Hospital55 fruit Stwhite 270bostonMA02114

摘要目的探讨CT扫描条件(80kv、100kv;管电流:75～150mA)、自适应迭代重建技术(ASIR)对尿路结石病人的影像质量的影响。材料与方法本研究符合HIPAA规定并获得伦理审查委员会批准,前瞻性低剂量CT扫描获得了病人知情同意,

关键词：尿路结石影像质量辐射剂量 ASIR CT

B-L model with d_(4)×Z_(4)×Z_(2)symmetry for fermion mass hierarchies and mixings

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Chinese Physics C 2024年第6期48卷 11-30页

作者： v.v.vien department of Physics Tay Nguyen UniversityDaklakVietnam

We constructed a gauge B-L model with d_(4)×Z_(4)×Z_(2)symmetry to explain the quark and lepton mass hierarchies and their mixings with realistic CP phases via the type-I seesaw *** quark mases,three quark mixing angles,and the CP phase in the quark sector take the central values whereas Yukawa couplings in the quark sector are diluted in a range of difference of three orders of magnitude by the perturbation theory at the first *** the neutrino sector,a small neutrino mass is achieved by the type-I seesaw *** inverted and normal neutrino mass hierarchies are consistent with the experimental *** predicted sum of neutrino masses for normal and inverted hierarchies,the effective neutrino masses,and the dirac CP phase are also consistent with recently reported limits.

关键词： flavor symmetries quark and lepton masses and mixing extensions of electroweak gauge sector neutrino mass and mixing non-standard-model neutrinos right-handed neutrinos d4 discrete symmetry

Kinetics of dense plasma in the field of short laser pulses:A generalized approach

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Matter and Radiation at Extremes 2024年第5期9卷 87-92页

作者： v.A.Astapenko v.S.Lisitsa Moscow Institute of Physics and Technology(National Research University) Institutskii per.9141701 DolgoprudnyiRussia National Research Centre“Kurchatov Institute ”123182 MoscowRussia National Research Nuclear University MEPhI 115409 MoscowRussia

A generalized kinetic model of atomic level populations in an optically dense plasma excited by laser pulses of arbitrary duration is formulated and *** model is based on a nonstationary expression for the probability of excitation of an atomic transition and takes into account the effects of laser pulse penetration into an optically dense medium.A universal formula for the excitation probability as a function of time and propagation length is derived and applied to the case of a Lorentzian spectral profile of an atomic transition excited by a laser pulse with a Gaussian *** features of nonstationary excitation probabilities are presented for different optical depths of the plasma,laser pulse durations,and carrier *** formulas derived here will be useful for the description of atomic populations excited by laser pulses under realistic conditions of dense plasmas.

关键词： laser excitation excited

Polariton lasing in Mie-resonant perovskite nanocavity

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Opto-Electronic Advances 2024年第4期7卷 27-42页

作者： Mikhail A.Masharin daria Khmelevskaia valeriy I.Kondratiev daria I.Markina Anton d.Utyushev dmitriy M.dolgintsev Alexey d.dmitriev vanik A.Shahnazaryan Anatoly P.Pushkarev Furkan Isik Ivan v.Iorsh Ivan A.Shelykh Hilmi v.demir Anton K.Samusev Sergey v.Makarov UNAM-Institute of Materials Science and Nanotechnology National Nanotechnology Research CenterDepartment of Electrical and Electronics EngineeringDepartment of PhysicsBilkent UniversityAnkara 06800Turkey ITMO University School of Physics and EngineeringSt.Petersburg 197101Russia Abrikosov Center for Theoretical Physics MIPTDolgoprudnyiMoscow Region 141701Russia LUMINOUS!Center of Excellence for Semiconductor Lighting and displays School of Electrical and Electronic EngineeringSchool of Physical and Mathematical SciencesSchool of Materials Science and EngineeringNanyang Technological UniversitySingapore 639798Singapore department of Physics Engineering Physics and AstronomyQueen’s UniversityKingstonOntario K7L 3N6Canada Science Institute University of IcelandDunhagi 3IS-107ReykjavikIceland Experimentelle Physik 2 Technische Universität DortmundDortmund 44227Germany Qingdao Innovation and development Center Harbin Engineering UniversityQingdao 266000China

deeply subwavelength lasers(or nanolasers)are highly demanded for compact on-chip bioimaging and sensing at the *** of the main obstacles for the development of single-particle nanolasers with all three dimensions shorter than the emitting wavelength in the visible range is the high lasing thresholds and the resulting *** we ex-ploit exciton-polariton condensation and mirror-image Mie modes in a cuboid CsPbBr3 nanoparticle to achieve coherent emission at the visible wavelength of around 0.53μm from its ultra-small(≈0.007μm3 or≈λ3/20)semiconductor *** polaritonic nature of the emission from the nanocavity localized in all three dimensions is proven by direct com-parison with corresponding one-dimensional and two-dimensional waveguiding systems with similar material *** a deeply subwavelength nanolaser is enabled not only by the high values for exciton binding energy(≈35 mev),re-fractive index(>2.5 at low temperature),and luminescence quantum yield of CsPbBr3,but also by the optimization of po-laritons condensation on the Mie resonances with quality factors improved by the metallic ***,the key parameters for optimal lasing conditions are intermode free spectral range and phonons spectrum in CsPbBr3,which govern polaritons condensation *** chemically synthesized colloidal CsPbBr3 nanolasers can be potentially de-posited on arbitrary surfaces,which makes them a versatile tool for integration with various on-chip systems.

关键词： nanolaser perovskite polariton Mie resonance exciton-polariton

Exploring one material for dual applications:A red-emitting Mg2GeO4:Eu3+ nanophosphor for future generation energy efficient WLEds and dosimetric applications

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Journal of Rare Earths 2024年第10期42卷 1835-1845页

作者： Akshay Arjun G.P.darshan S.C.Sharma H.Nagabhushana d.v.Sunitha H.B.Premkumar department of Physics Faculty of Mathematical and Physical SciencesM.S.Ramaiah University of Applied Sciences Jain University C.N.R.Rao Centre for Advanced Materials Tumkur University School of Applied Sciences (Physics) REVA University

The envisaged design and developme nt of individual mate rials to excavate a broader spectrum of desired properties and offer multiple applications are highly *** this in mind,a series of forsterite-structured Mg2GeO4:Eu3+（1 mol%-9 mol%） nanophosphors was synthesized via a solution combustion method using oxalyl dihydrazide as a *** X-ray diffraction patterns confirm the orthorhombic crystal system with a Puma space *** results clearly show irregularly shaped cluster-like structures with aggregation of the *** diffuse reflectance spectra,the optical energy band gap of the Mg2GeO4:Eu3+（1 mol%-9 mol%） nanophosphors was estimated and obtained to be～4.12-4.32 *** photoluminescence emission spectra exhibit intense peaks at ～579,589,610,661,and 707 nm,which are due to characteristic5d0→7F0,5d0→7F1,5do→7F2,5d0→7F3and5d0→7F4transitions of Eu3+ions,*** Commission International de L'Eclairage color coordinates are gradually tuned from pale red（0.5980,0.4012） to a pure red（0.6385,0.3611） *** glow peaks showcase excellent super-linear response at low doses of γ-irradiations,indicating that the prepared phosphor can be used in thermoluminescent personal dosimetry which is a biological tissue *** aforementioned results demonstrate that the prepared Mg2GeO4:Eu3+（1 mol%-9 mol%） nanophosphors are considered an excellent candidate for dual applications,i.e.,red component in future generation white-light-emitting diodes（WLEds） and personal dosimetric applications.

关键词： dosimetry Nanophosphors Photoluminescence Photometric properties Rare earths Thermoluminescence

Highly defective dark TiO_(2) Modified with Pt: Effects of Precursor Nature and Preparation Method on Photocatalytic Properties

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Transactions of Tianjin University 2024年第2期30卷 198-209页

作者： E.d.Fakhrutdinova O.A.Reutova T.A.Bugrova I.Yu.Ovsyuk L.S.Kibis O.A.Stonkus d.B.vasilchenko O.v.vodyankina v.A.Svetlychnyi National Research Tomsk State University TomskRussia 634050 Novosibirsk State University NovosibirskRussia 630090 Boreskov Institute of Catalysis NovosibirskRussia 630090 Nikolaev Institute of Inorganic Chemistry NovosibirskRussia 630090

The study focused on the modification with platinum of dark defective titania obtained via pulsed laser ablation. Both the method of Pt introduction and the nature of the Pt precursor were varied. All samples exhibited similar phase compositions, specific surface areas, and Pt contents. High-resolution transmission electron microscopy coupled with pulsed CO adsorption revealed increased dispersity when photoreduction and the hydroxonitrate complex (Me _(4) N) _(2) [Pt _(2) (OH) _(2) (NO _(3) ) _(8) ] were used. The sample featured a high content of single-atom species and subnano-sized Pt clusters. The X-ray photoelectron spectroscopy results showed that the photoreduction method facilitated the appearance of a larger number of Pt ^(2+) states, which appeared owing to the strong metal-support interaction (SMSI) eff ect of the transfer of electron density from the electron-saturated defects on the TiO _(2) surface to Pt ^(4+) . In the hydrogen evolution reaction, samples with a significant fraction of the Pt ^(2+) ionic component, capable of generating short-lived Pt^(0) single-atom sites under irradiation due to the SMSI eff ect, exhibited the highest photocatalytic activity. The 0.5Pt(C)/TiO_(2) -Ph sample exhibited the highest hydrogen yield with a quantum efficiency of 0.53, retaining its activity even after 8 h of operation.

关键词： dark(black)TiO_(2) Pulsed laser ablation Platinum reduction method Precursor type Photocatalysis Hydrogen evolution reaction