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Chinese Physics B 2013年第7期22卷 226-231页

作者：王河林杨爱军冷雨欣 college of science Zhejiang University of Technology State Key Laboratory of High field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciences

A novel high-birefringence photonic crystal fiber （HB-PCF） with two zero-dispersion wavelengths （ZDWs） is designed, and an extraordinarily high modal birefringence of 1.56×10-2 is obtained at pump wavelength λp=1850nm. With the designed HB-PCF, the effect of the pump parameters on the modulation instability （MI） in the anomalous dispersion region close to the second ZDWs of the HB-PCF is comprehensively studied in this work. A broadband and tunable optical amplification is achieved by controlling the pump power and the pump wavelength based on the combined operation of Raman effect and cross phase modulation. By optimizing the pump parameters, the amplification bandwidth along the fiber slow axis reaches 152 nm for the pump power Pp=280W and the pump wavelength λp=1675nm, while the gain bandwidth along the fiber fast axis is 165 nm for the pump power Pp=600W and the pump wavelength λp=1818nm.

关键词： modulation instability broadband amplification high-birefringence fiber

Hard-thermal-loop QED thermodynamics

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Chinese Physics C 2010年第9期34卷 1527-1529页

作者：苏楠 Jens O.Andersen Michael Strickland Frankfurt institute for advanced Studies Department of Physics Norwegian University of Science and Technology Department of Physics Gettysburg College

The weak-coupling expansion for thermodynamic quantities in thermal field theories is poorly convergent unless the coupling constant is *** discuss the calculation of the free energy for a hot gas of electrons and photons to three-loop order using hard-thermal-loop perturbation theory （HTLpt）.We show that the hard-thermal-loop perturbation reorganization improves the convergence of the successive approximations to the QED free energy at large coupling,e ～ *** reorganization is gauge invariant by construction,and due to the cancellations among various contributions,we obtain a completely analytic result for the resummed thermodynamic potential at three loops.

关键词： resummation hard-thermal-loop thermal field theory QED free Energy

Cs 728 nm Laser Spectroscopy and Faraday Atomic Filter

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Chinese Physics Letters 2014年第12期31卷 27-30页

作者：刘忠征陶智明蒋招杰陈景标 State Key Laboratory of advanced Optical Communication System and Network Institute of Quantum Electronics School of Electronics Engineering ~ Computer Science Peking University Beijing 100871 college of science Guizhou University of Engineering Science Bijie 551700

The laser spectroscopy of alkali-metal vapor is widely used in a number of applications, such as the Faraday anomalous dispersion optical fil- ter （FADOF）, the active optical clock, and wavelength ***＇ The Cs electrodeless dis- charge vapor lamp has rich spectra, including 455 nm, 459 nm, 728 nm, 852 nm, 1359 nm, and 1470 nm. The 852 nm laser pumping atoms from 6S1/2 to 6P3/2 have been used in *** 1359nm wave- length transited from 7S1/2 to 6P1/2 of Cs atoms can be used in the field of active optical clocks. The concept of active optical clocks has been proposed since 2005. Due to its good performance in sta- bility, the active optical clock has been extensively in- vestigated theoretically and experimentally in recent years, such as the two-level active optical clock, and three-level active optical clock. When considering the performance of the active optical clock, we hope to reduce the second-order Doppler shift in thermal atomic beam and the light shift induced by the pump- ing laser. To solve this issue, our group has recently proposed a four-level active optical clock, such as K 1252.2nm, Cs 1469nm, Rb 1366.9nm and Rb 728 nm. Moreover, the Rb 728 nm four-level quantum system has potentially a better performance than three long wavelength ones of Rb.

关键词： LASER spectroscopy CESIUM FARADAY effect INDUCTION lamps PHASE transformations (Physics) LIGHT filters

Pyramid-VAE-GAN:Transferring hierarchical latent variables for image inpainting

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Computational Visual Media 2023年第4期9卷 827-841页

作者： Huiyuan Tian Li Zhang Shijian Li Min Yao Gang Pan college of Computer science and Technology Zhejiang UniversityHangzhou 310027China advanced Technology Research institute Zhejiang UniversityHangzhou 310027China

Significant progress has been made in image inpainting methods in recent ***,they are incapable of producing inpainting results with reasonable structures,rich detail,and sharpness at the same *** this paper,we propose the Pyramid-VAE-GAN network for image inpainting to address this *** network is built on a variational autoencoder(VAE)backbone that encodes high-level latent variables to represent complicated high-dimensional prior distributions of *** prior assists in reconstructing reasonable structures when *** also adopt a pyramid structure in our model to maintain rich detail in low-level latent *** avoid the usual incompatibility of requiring both reasonable structures and rich detail,we propose a novel cross-layer latent variable transfer *** transfers information about long-range structures contained in high-level latent variables to low-level latent variables representing more detailed *** further use adversarial training to select the most reasonable results and to improve the sharpness of the *** experimental results on multiple datasets demonstrate the superiority of our *** code is available at https://***/thy960112/Pyramid-VAE-GAN.

关键词： image inpainting variational autoencoder(VAE) latent variable transfer(LTN) pyramid structure generative model

Incorporating element doping and quantum dot embedding effects to enhance the thermoelectric properties of higher manganese silicides

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Journal of Materiomics 2021年第2期7卷 377-387页

作者： Qing Wang Shiyu Song Xiaofeng Yang Ziyang Liu Yufei Ma Xingyuan San Jianglong Wang Dan Zhang Shu-Fang Wang Zhiliang Li Key Laboratory of High-precision Computation and Application of Quantum field Theory of Hebei Province College of Physics Science and TechnologyHebei UniversityBaoding071002China institute of life science and Green Development Hebei UniversityBaoding071002China

Element doping and nano-inclusion embedding are effective approaches to enhance the electrical conductivities and decrease the lattice thermal conductivities of thermoelectric(TE)materials,***,the intrinsic low electrical thermal conductivities and high electrical properties are severely sacrificed,and the final figure of merit(ZT)is usually *** this study,Ag doping and Pt quantum dot(QD)embedding were synchronously achieved via embedding Ag/Pt alloy QDs into the higher manganese silicides to avoid the conventional single-element doping *** power factor(at 823 K)was enhanced from 1.57×10^(-3) W m^(-1) K^(-2) to 1.82×10^(-3) W m^(-1) K^(-2)(-16%)due to the-18%increase in carrier concentration that was derived from the Ag doping ***,the lattice thermal conductivity(at 823 K)decreased from 2.65 W m^(-1) K^(-1) e1.92 W m^(-1) K^(-1)(-28%)because of the broadband phonon scattering effect that resulted from the residual Pt QDs ***,the optimal ZT value increased by-52%from 0.42 to 0.64 at 823 *** study demonstrated that incorporating metastable alloy QDs to obtain element doping and nano-inclusion embedding effects is a novel and feasible means to enhance the ZT value of *** method is also possibly applicable to other alloy QD/TE composites.

关键词： Quantum dot Inclusion Higher manganese silicide Thermoelectric material Figure of merit

Semi-interpenetrating network anion exchange membranes based on quaternized polyvinyl alcohol/poly(diallyldimethylammonium chloride)

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Green Energy & Environment 2021年第5期6卷 743-750页

作者： Xinming Du Hongyu Zhang Yongjiang Yuan Zhe Wang college of Chemical Engineering Changchun University of TechnologyChina School of Materials science and Engineering Changchun University of TechnologyChina advanced institute of Materials science Changchun University of TechnologyChangchun130012China

The semi-interpenetrating network anion exchange membranes(AEMs)based on quaternized polyvinyl alcohol(QPVA)and poly(-diallyldimethylammonium chloride)(PDDA)are *** chemical cross-linking structure is formed between hydroxyl groups of QPVA and aldehyde groups of glutaraldehyde(GA),which makes PDDA more stable embed in the QPVA matrix and also improves the mechanical properties and dimensional stability of *** to the phase separation phenomenon of AEMs swelling in water,a microporous structure may be formed in the membrane,which reduces the transmission resistance of hydroxide ions and provides a larger space for the transfer of hydroxide ions,thus improving the *** ring structure of PDDA is introduced as a cationic group to transfer hydroxide ions,and shields the nucleophilic attack of the hydroxide ions through the steric hindrance effect,which improves alkaline *** hydroxide conductivity of semi-interpenetrating network membrane(QPVA/PDDA0.5-GA)is 36.5 mS cm^(-1) at 60℃.And the membrane of QPVA/PDDA0.5-GA exhibits excellent mechanical property with maximum tensile strength of 19.6 *** immersing into hot 3 mol L^(-1) NaOH solutions at 60℃ for 300 h,the OHconductivity remains 78%of its initial *** semi-interpenetrating network AEMs with microporous structure exhibit good ionic conductivity,mechanical strength and alkaline durability.

关键词： Anion exchange membrane Semi-interpenetrating network cross-linked Microporous structure

Structure and intrinsic magnetic properties of Sm_(1-x)Pr_xCo_5(x=0–0.6) compounds

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Rare Metals 2016年第8期35卷 627-631页

作者： Miao-Ling Xu Ming Yue Yu-Qing Li Qiong Wu Yun Gao college of Materials science and Engineering Beijing University of TechnologyBeijing 100124China Samsung advanced institute of Technology Beijing 100028China

In this work, the effects of Pr content on the structure and intrinsic magnetic properties of Sml-xPrxCO5 （x = 0-0.6） compounds prepared by induction melting were systematically investigated by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, and magnetic measurements. Microstructural observation and chemical composition analysis show that Sml xPrxCos compounds are composed of （Sin, Pr）Co （1：5） phase and （Sm, Pr）-rich grain boundary phase. XRD results show that all the Sml-xPrxCO5 compounds have a （Sm, Pr）lCo main phase with the hexagonal CaCus-type crystal structure and the （Sm, Pr）2 Co7 impurity phase. In addition, the detailed research shows that the lattice constants （a, c） and unit volume （V） are all enlarged with the increases in Pr con- tent. According to the magnetic measurements, as the Pr content increases to larger than 0.4, both the Curie tem- perature （Tc） and the anisotropy field （HA） of all the Pr- doped compounds decrease rapidly. Meanwhile, the mag- netization of Sml_***5 compounds at applied field of 14 T （MI4 T） are observably improved with Pr doping content of x 〉 0.3. Among them, Smo.6Pro.4Co5 compound exhibits slightly lower HA and Tc, but much higher M14 T than those of the binary SmCos, indicating that doping of proper Pr content into SmCo5 compound can optimize the intrinsic magnetic properties. As a result, the optimal intrinsic magnetic properties of HA = 29.11 T,Tc = 989 K, and M14 T = 102.31 mA.m2.g-1 are obtained in Smo.6Pro.4C05 compound.

关键词： Sml-xPrxCo5 compounds Microstructure Crystal structure Intrinsic magnetic property

Effect of Annealing Temperature on Electrical Properties of Ferroelectric Bi3.25La0.75Ti3O12 Capacitors

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Chinese Physics Letters 2007年第12期24卷 3559-3562页

作者：闫正张未涛王毅张新李丽赵庆勋杜军刘保亭 college of Physics science and Technology Hebei University Baoding 071002 institute of advanced Electronic Materials General Research Institute for Non-ferrous Metals Beijing 100088

Lanthanum-modified bismuth titanate （Bi3.25La0.75 Ti3 O12, BLT） thin films are fabricated on platinized Si wafers by the sol-gel method, and the effect of annealing temperatures ranging from 650℃ to 800℃ on the electrical properties of Pt/BLT/Pt capacitors are investigated. It is found that polarization and leakage current of BLT capacitors strongly depend on the annealing temperature although all the capacitors demonstrate very similar characteristics, except the value of polarization, in pulse-width dependence, retention, and fatigue. Remanent polarization increases with the increase of annealing temperature, and annealing temperature of 700℃ can yield the largest remanent polarization, and then polarization decreases with increasing annealing temperature. For the 700℃ annealed Pt/BLT/Pt capacitor, the remanent polarization 2Pr and the coercive field 2Ec, at an electric field of 226 k V/cm, are 23.8μC/cm^2 and 130 k V/cm, respectively. Dielectric breakdown voltages of BLT films annealed at 750℃ and 800℃ are much lower than those annealed at 650℃ and 700℃. At 100 kV/cm, the leakage currents of BLT films prepared at 650℃ and 700℃ are only 1.5 ×10^-6 A/cm2 and 8.9 ×10^-7 A/cm2, respectively. Moreover, all the Pt/BLT/Pt capacitors exhibit excellent retention properties after a cumulative time of 1×10^4 s and do not show any significant fatigue up to 1×10^10 switching cycles at frequency of i MHz.

关键词： thermoelectric half-Heusler compounds thermal conductivity

Genetic diversity for mycorrhizal symbiosis and phosphate transporters in rice

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Journal of Integrative Plant Biology 2015年第11期57卷 969-979页

作者： Kwanho Jeong Nicolas Mattes Sheryl Catausan Joong Hyoun Chin Uta Paszkowski Sigrid Heuer Southern cross Plant science Southern Cross University International Rice Research institute(IRRI) Crop and Environmental Sciences Division Seoul National University College of Agriculture and Life SciencesPlant Genomics and Breeding Institute University of Cambridge Department of Plant Sciences Australian Center For Plant Functional Genomics(ACPFG)

Phosphorus （P） is a major plant nutrient and developing crops with higher P-use efficiency is an important breeding goal. In this context we have conducted a comparative study of irrigated and rainfed rice varieties to assess genotypic differences in colonization with arbuscular mycorrhizal （AM） fungi and expression of different P trans- porter genes. Plants were grown in three different soil samples from a rice farm in the Philippines. The data show that AM symbiosis in all varieties was established after 4 weeks of growth under aerobic conditions and that, in soil derived from a rice paddy, natural AM populations recovered within 6 weeks. The analysis of AM marker genes （AM1, AM3, AM14） and P transporter genes for the direct Pi uptake （PT2, PT6） and AM-mediated pathway （PTll, PT13） were largely in agreement with the observed root AM colonization providing a useful tool for diversity studies. Interestingly, delayed AM colonization was observed in the aus-type rice varieties which might be due to their different root structure and might confer an advantage for weed competition in the field. The data further showed that P-starvation induced root growth and expression of the high-affinity P transporter PT6 was highest in the irrigated variety IR66 which a]so maintained grain yield under P-deficient field conditions.

关键词： Mycorrhiza P deficiency tolerance phosphatetransporters rice roots

SPAGINS:semiempirical parameterization for fragments in gamma-induced nuclear spallation

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Nuclear science and Techniques 2023年第12期34卷 112-122页

作者： Hui‑Ling Wei Meng‑Die Zhou Pu Jiao Yu‑Ting Wang Jie Pu Kai‑Xuan Cheng Ya‑Fei Guo Chun‑Yuan Qiao Gong‑Tao Fan Hong‑Wei Wang Chun‑Wang Ma institute of Particle and Nuclear Physics College of PhysicsHenan Normal UniversityXinxiang 453007China Shanghai advanced Research institute Chinese Academy of SciencesShanghai 201204China institute of Nuclear science and Technology Henan Academy of ScienceZhengzhou 450046China

From the empirical phenomena of fragment distributions in nuclear spallation reactions,semiempirical formulas named SPAGINS were constructed to predict fragment cross-sections in high-energyγ-induced nuclear spallation reactions(PNSR).In constructing the SPAGINS formulas,theoretical models,including the TALYS toolkit,SPACS,and Rudstam formulas,were employed to study the general phenomenon of fragment distributions in PNSR with incident energies ranging from 100 to 1000 *** the primary characteristics of PNSR,the SPAGINS formulas modify the EPAX and SPACS formulas and efficiently reproduce the measured *** SPAGINS formulas provide a new and effective tool for predicting fragment production in PNSR.

关键词： High-energy gamma-rays Spallation reaction Fragment cross-section Empirical formula EPAX SPACS TALYS