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Ultraviolet to visible frequency-conversion properties of rare earths doped glass ceramics

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Journal of Rare Earths 2011年第5期29卷 484-488页

作者： Y.Hatefi N.Shahtahmasebi A.Moghimi E.Attaran department of {1. Imam Hossein University Nano-Research Centre of the Ferdowsi University of Mashhad department of {1. Ferdowsi University of Mashhad department of Chemistry Imam Hossein University

Nd3＋,Eu3＋ and Tb3＋ ions doped transparent chlorophosphate glass ceramics were prepared and their frequency-conversion properties were studied. X-ray diffraction （XRD） patterns evidenced the formation of expected halide nanocrystals. The absorption,excitation and emission spectra investigation indicated that some of rare earth （RE） ions were trapped in low phonon energy halide nanocrystals,and therefore an efficient down frequency-conversion was observed. The comparative spectroscopic studies of RE doped samples suggested that the glass ceramics systems are potentially applicable as efficient ultraviolet to visible frequency-conversion photonics materials.

关键词： chlorophosphate glass down frequency-conversion glass ceramic photonic devices nanocrystal rare earth ions

ISOTHERMAL CRYSTALLIZATION BEHAVIOR AND UNIQUE BANDED SPHERULITES OF HYDROXYAPATITE/POLY(L-LACTIDE) NANOCOMPOSITES

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Chinese Journal of Polymer Science 2010年第4期28卷 499-507页

作者：陈学思 State Key Laboratory of Polymer physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences Graduate School of Chinese Academy of Sciences

Hydroxyapatite/poly（L-lactide）（HA/PLLA） nanocomposites were prepared by the solvent mixing method. The isothermal crystallization behavior was studied by differential scanning calorimetry （DSC） and polarized optical microscopy （POM）. The results show that the crystallization behavior of HA/PLLA composites was strongly affected by the content of HA and crystallization temperature, and the addition of HA could promote nucleation and enhance the crystallization rate. When isothermal crystallization was carried out at 1.0℃, the HA/PLLA nanocomposite with 1. HA content crystallized most rapidly among all the composites and the half crystallization time was only 1.0 min. Banded spherulites were observed for the HA/PLLA composites, but no banded spherulites were seen in the crystals of PLLA under the same condition.

关键词： Hydroxyapatite Polylactide Crystallization Nanocomposites Spherulites

Metallized siligraphene nanosheets （SiC7） as high capacity hydrogen storage materials

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Nano Research 2018年第7期11卷 3802-3813页

作者： Syeda R. Naqvi Tanveer Hussain Wei Luo Rajeev Ahuja Condensed Matter Theory Group Department of Physics and Astronomy Box 516 Uppsala University S-75120 Uppsala Sweden applied Materials {1. Department of Materials and Engineering Royal Institute of Technology (ICFH) S-10044 Stockholm Sweden Centre for Theoretical and Computational Molecular Science Australian Institute for Bioengineering and Nanotechnology The University of Queensland Brisbane Old 4072 Australia

A planar honeycomb monolayer of siligraphene （SIC7） could be a prospective medium for clean energy storage due to its light weight, and its remarkable mechanical and unique electronic properties. By employing van der Waals- induced first principles calculations based on density functional theory （DFT）, we have explored the structural, electronic, and hydrogen （H2） storage characteristics of SiC7 sheets decorated with various light metals. The binding energies of lithium （Li）, sodium （Na）, potassium （K）, magnesium （Mg）, calcium （Ca）, scandium （Sc）, and titanium （Ti） dopants on a SiC7 monolayer were studied at various doping concentrations, and found to be strong enough to counteract the metal clustering effect. We further verified the stabilities of the metallized SiC7 sheets at room temperature using ab initio molecular dynamics （MD） simulations. Bader charge analysis revealed that upon adsorption, due to the difference in electronegativity, all the metal adatorns donated a fraction of their electronic charges to the SiC7 sheet. Each partially charged metal center on the SiC7 sheets could bind a maximum of 4 to 5 H2 molecules. A high H2 gravimetric density was achieved for several dopants at a doping concentration of 1..50%. The H2 binding energies were found to fall within the ideal range of 0.2-0.6 eV. Based on these findings, we propose that metal-doped SiC7 sheets can operate as efficient H2 storage media under ambient conditions.

关键词： dean energy functionalization binding characteristics dopants

Strongly lensed gravitational waves as probes to test the cosmic distance duality relation

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Chinese physics C 2021年第1期45卷 406-413页

作者： Hai-Nan Lin Xin Li Li Tang department of {1. Chongqing UniversityChongqing 401331China department of Math and {1. Mianyang Normal UniversityMianyang 621000China

The cosmic distance relation(DDR) associates the angular diameters distance(DA) and luminosity distance(DL) by a simple formula,i.e.,DL=(1.z)2 *** strongly lensed gravitational waves(GWs) provide a unique way to measure DA and DL simultaneously to the GW source,hence they can be used as probes to test *** this study,we investigated the use of strongly lensed GW events from the future Einstein Telescope to test *** assumed the possible deviation of DDR as(1.z)2 DA/DL=η(z),and considered two different parametrizations of η(z),namely,η1.z)=1.η0 z and η2(z)=1.η0 z/(1.z).Numerical simulations showed that,with about 1.0 strongly lensed GW events observed by ET,the parameter η0 was constrained at 1.3% and 3% levels for the first and second parametrizations,respectively.

关键词： gravitational waves gravitational lensing cosmology

OBSERVATION AND MEASURMENT OF THE AUTOIONIZATION SPECTRA OF ATOMIC SAMARIUM

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Chinese physics Letters 1989年第2期6卷 64-67页

作者： HU Sufen MEI Shimin ZHANG Sen CHEN Xing XU Yunfei department of {1. Zhejiang UniversityHangzhou

Autoionization spectra of atomic samarium have been observed using the stepwise laser excitation *** than fifty autoionizating levels of Sm which are located in the 45793.9-48045.4cm^(-1. energy interval with odd pari... 详细信息

关键词： method. excitation stepwise

String Cosmological Solutions with O(d,d) Duality Symmetry and Matter Coupling

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Communications in Theoretical physics 2013年第1期59卷 43-46页

作者：李宝霖颜骏 department of {1. Sichuan Normal University

The duality properties of string cosmology model with negative energy matter are investigated by means of renormalization group equation,the cosmological solutions with exotic matter coupling are obtained in D=d+1.dimensional *** inflation-power solutions can describe accelerated and decelerated process in the early universe,and the duality solutions can be generated through O(d,d) transformations.

关键词： O(d d) duality symmetry cosmological solutions matter coupling renormalization group equa-tion

Bi-large Neutrino Mixing See-Saw Mass Matrix with Texture Zeros and Leptogenesis

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Communications in Theoretical physics 2006年第6期45卷 1073-1084页

作者： CHAO Wei HE Xiao-Gang LI Xue-Qian department of {1. Nankai University Tianjin 300071 China NCTS/TPE Department of Physics National Taiwan University Taipei China

We study constraints on neutrino properties for a class of bi-large mixing See-Saw mass matrices with texture zeros and with the related Dirac neutrino mass matrix to be proportional to a diagonal matrix of the form diag （e, 1. 1.. Texture zeros may occur in the light （class a）） or in the heavy （class b）） neutrino mass matrices. Each of these two classes has 5 different forms which can produce non-trivial three generation mixing with at least one texture zero. We tind that two types of texture zero mass matrices in both class a and class b can be consistent with present data on neutrino masses and mixing. None of the neutrinos can have zero masses and the lightest of the light neutrinos has a mass larger than about 0.046 eV for class a and 0.0027 eV for class b. In these models although the CK.M CP violating phase vanishes, the non-zero Majorana phases can exist and can play an important role in producing the observed baryon asymmetry in our universe through leptogenesis mechanism. The requirement of producing the observed baryon asymmetry can further distinguish different models and also restrict the See-Saw scale to be in the range of 1.^1.- 1.^1. GeV. We also discuss RG effects on V^1..

关键词： neutrino neutrino mass matrix neutrino masses and mixing bi-large mixing matrix

Isospin dependence of projectile fragmentation and neutron-skin thickness of neutron-rich nuclei

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Chinese physics C 2011年第11期35卷 1017-1021页

作者：马春旺王闪闪 department of {1. Henan Normal University

By investigating the cross section distributions of fragments produced in the 1.0 A MeV 40,48Ca＋9Be and 1.A GeV 1.4,1.6Xe＋Pb reactions, the isospin dependence of projectile fragmentation in fragment production is studied. In the framework of the statistical abrasion-ablation model, the 1.A GeV 1.6Xe＋ 208Pb reaction is calculated. By adjusting the diffuseness parameter in neutron density distribution of 1.6Xe, we find the isospin dependence of projectile fragmentation in fragment production is sensitive to the neutron-skin thickness of the projectile nucleus.

关键词： heavy-ion collisions isospin effect projectile fragmentation

Detecting anomalies in vector boson scattering

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Chinese physics C 2021年第7期45卷 51-64页

作者： Jinmian Li Shuo Yang Rao Zhang College of physics Sichuan UniversityChengdu 610065China department of {1. Liaoning Normal UniversityDalian 116029China department of {1. Dalian UniversityDalian 116622China

Measuring vector boson scattering(VBS)precisely is an important step toward understanding the electroweak symmetry breaking of and detecting new physics beyond the standard model(SM).Herein,we propose a neural network that compresses the features of the VBS data into a three-dimensional latent *** consistency of the SM predictions and experimental data is tested via binned log-likelihood analysis in the latent *** show that the network is capable of distinguishing different polarization modes of WWjj production in both di-and semileptonic *** method is also {1. to constrain the effective field theory and two Higgs Doublet *** results demonstrate that the method is sensitive to general new physics contributing to the VBS.

关键词： LHC electroweak symmetry breaking Higgs boson machine learning