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Zinc-oxide nanoparticle-based saturable absorber deposited by simple evaporation technique for Q-switched fiber laser

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Chinese Physics B 2019年第8期28卷 167-171页

作者： syarifah Aloyah syed Husin Farah Diana Muhammad che Azurahanim che Abdullah siti Huzaimah Ribut Mohd Zamani Zulkifli Mohd Adzir Mahdi Department of Physics Faculty of ScienceUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia Photonics Research Centre Department of PhysicsUniversity of Malaya50603 Kuala LumpurMalaysia Kulliyyah of science International Islamic University of MalaysiaJalan Sultan Ahmad ShahBandar Indera Mahkota25200 KuantanPahangMalaysia Wireless and Photonics Networks Research Centre Faculty of EngineeringUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia

A Q-switched erbium-doped fiber laser(EDFL)incorporating zinc-oxide(ZnO)nanoparticles-based saturable absorber(sA)is proposed and *** form the sA,the ZnO nanoparticles,which are originally in the powder form,are first dissolved in ethanol and subsequently deposited onto the surface of fiber ferrule by using the adhesion effect with the evaporation *** integrating the ZnO nanoparticle-based sA into a laser cavity of an EDFL,a self-started and stable Q-switching is achieved at a low threshold power of 20.24 *** the pump power is increased,the pulse repetition rate is tunable from 10.34 kHz to 25.59 kHz while pulse duration decreases from 21.39μs to 3.65μ***,this Q-switched laser has a maximum energy per pulse of 19.34 nJ and an average output power of 0.46 *** results indicate the feasibility and functionality of the ZnO nanoparticles-based sA for Q-switched generation,which offers the flexibility and easy integration of the sA into a ring laser cavity.

关键词： zinc oxide saturable absorber Q-switched fiber laser

Routeview:an intelligent route planning system for ships sailing through Arctic ice zones based on big Earth data

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International Journal of Digital Earth 2022年第1期15卷 1588-1613页

作者： Adan Wu Tao che Xin Li Xiaowen Zhu Key Laboratory of Remote sensing of Gansu Province Heihe Remote Sensing Experimental Research StationNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouPeople’s Republic of China University of Chinese Academy of sciences BeijingPeople’s Republic of China CAs Center for Excellence in Tibetan Plateau Earth sciences Beijing China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijingPeople’s Republic of China Gansu Forestry Polytechnic TianshuiPeople’s Republic of China

The potential of Arctic routes(ARs)has attracted global attention,and exploiting the Arctic has become an important strategy for many ***,there are still some challenges for ships sailing in Arctic ice zones,including harsh marine environments and the insufficient service capacity of sea ice information service *** better understand the route changes in the Arctic and extract real-time ship navigation routes,we developed an online interactive route planning system(RouteView)for ships sailing in the Arctic based on big Earth *** includes two main features:(1)an online calculation interface is provided for optimal routes along the Arctic Northeast Passage(NEP)60 days into the future by utilizing reinforcement learning(RL)based on sea ice and meteorological data,and(2)an online ice-water classification is established based on synthetic aperture radar(sAR)data and deep learning to help users extract the sea ice distribution in real *** work can potentially enhance the safety of shipping navigation along the NEP and improve information extraction methods for ARs.

关键词： Arctic northeast passage information extraction system reinforcement learning U-Net route planning ice-water classification

suitability projection for Chinese ski areas under future natural andsocioeconomic scenarios

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Advances in Climate Change Research 2021年第2期12卷 224-239页

作者： DENG Jie che Tao JIANG Tong DAI Li-Yun Heihe Remote sensing Experimental Research station Key Laboratory of Remote Sensing of Gansu ProvinceNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China Center for Excellence in Tibetan Plateau Earth sciences Chinese Academy of SciencesBeijing100101China University of Chinese Academy of sciences Beijing100049China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disaster School of Geographic SciencesNanjing University of InformationScience&TechnologyNanjing210044China Jiangsu Center of Collaborative Innovation in Geographical Information Resource Development and Application Nanjing210000China

ski tourism is extremely sensitive to climate change and is also heavily affected by socioeconomic *** some ski areas arestill profitable under current climate and socioeconomic conditions,they will become difficult to operate in the face of rising winter temper-atures,which will result in further economic losses,resource waste and environmental *** study projects variability in the suitability ofski area development across China in the coming *** suitability under three representative concentration pathway emission sce-narios(RCP2.6,RCP4.5 and RCP8.5),socioeconomic suitability under four shared socioeconomic pathways(ssP1,ssP2,ssP3,and ssP5)andintegrated suitability under four climatic-socioeconomic scenarios(RCP2.6-ssP1,RCP4.5-ssP2,RCP8.5-ssP3,and RCP8.5-ssP5)are ***,the suitability of 731 existing ski areas in China is *** results show a substantial decline in integrated suitabilityfor most regions of China except for some very cold areas,where higher air temperatures will make visitors feel more comfortable and therelatively poor socioeconomic conditions will improve in the 2030s,2050s and *** average higher integrated suitability area(integratedsuitability values greater than 0.5)under four climatic-socioeconomic scenarios decreases from the current 29.9%e14.4%,5.0%and 4.5%bythe 2030s,2050s and 2090s,*** RCP2.6-ssP1,the higher integrated suitability area is projected to decrease from the current28.0%e5.2%by the 2050s and then increase to 5.3%by the *** RCP4.5-ssP2,RCP8.5-ssP3,and RCP8.5-ssP5,the higher inte-grated suitability area is projected to continuously decrease from 30.3%,30.6%and 30.6%in the 2010s to 4.1%,4.4%and 4.4%in the 2090s,*** the 2090s,41,138 and 277 existing ski areas are projected to be closed under RCP2.6-ssP1,RCP4.5-ssP2,and RCP8.5-ssP3/RCP8.5-ssP5,*** is clear that emission pathways and climate change adaptation and mitigation

关键词： suitability ski tourism Climate change socioeconomic development China

Majorana stellar representation for mixed-spin (s, 1/2) systems

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Chinese Physics B 2021年第3期30卷 168-175页

作者： Yu-Guo su Fei Yao Hong-Bin Liang Yan-Ming che Li-Bin Fu Xiao-Guang Wang Zhejiang Province Key Laboratory of Quantum Technology and Device Department of PhysicsZhejiang UniversityHangzhou 310027China National Laboratory of science and Technology on Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China

By describing the evolution of a quantum state with the trajectories of the Majorana stars on a Bloch sphere,Majorana’s stellar representation provides an intuitive geometric perspective to comprehend the quantum system with highdimensional Hilbert ***,the representation of a two-spin coupling system on a Bloch sphere has not been solved satisfactorily ***,a practical method is presented to resolve the problem for the mixed-spin(s,1/2)system and describe the entanglement of the *** system can be decomposed into two spins:spin-(s+1/2)and spin-(s−1/2)at the coupling bases,which can be regarded as independent ***,any pure state may be written as a superposition of two orthonormal states with one spin-(s+1/2)state and the other spin-(s−1/2)***,the whole initial state can be regarded as a state of a pseudo spin-1/*** this way,the mixed spin decomposes into three ***,the state can be represented by(2s+1)+(2s−1)+1=4s+1 sets of stars on a Bloch ***,some examples are given to show symmetric patterns on the Bloch sphere and unveil the properties of the high-spin system by analyzing the trajectories of the Majorana stars on the Bloch sphere.

关键词： Majorana’s stellar representation Bloch sphere high-dimensional projective Hilbert space mixedspin

Effect of Microstructure of Cementite on Interphase stress state in Carbon steel

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Journal of Iron and steel Research International 2007年第4期14卷 31-38页

作者： che Lei GOTOH Masahide HORIMOTO Yoshiaki HIROsE Yukio Graduate school Kanazawa University Kanazawa 920-1192 Japan Department of Materials science and Engineering Kanazawa University Kanazawa 920-1192 Japan

The experiments related to stress states of ferrite and cementite in carbon steels were carried out including in situ four-point bending and tensile test by X-ray diffraction technique. stresses in the cementite phase can be measured by conventional X-ray diffraction instrument after a specific treatment on the specimen surface. In order to estimate the stress states in two phases, the X-ray elastic constants of two phases in single-phase state （PXEC） are determined by the experimental X-ray elastic constants of them in composite state （CXEC）. The effects of volume fraction and particle size of spheroidal cementite on the interphase stress state are estimated. The experimental results are in good agreement with the theoretical relationships reported in the previous studies.

关键词： multi-phase material surface treatment plastic deformation residual stress X-ray diffraction

Electrocatalytic reduction of CO_(2) on chiral Cu surfaces

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Chinese Journal of structural chemistry 2023年第8期42卷 1-3页

作者： Yuxi Fang Lu Han shunai che school of chemistry and chemical Engineering Frontiers Science Center for Transformative MoleculesState Key Laboratory of Metal Matrix CompositesShanghai KeyLaboratory for Molecular Engineering of Chiral DrugsShanghai Jiao Tong University800 Dongchuan RoadShanghai200240China school of chemical science and Engineering Tongji University1239 Siping RoadShanghai200092China

Carbon dioxide reduction products ranging from small molecules tobiomolecules are highly diverse in natural *** of carbon dioxide to produce a variety of products is one of themost efficient methods to understand *** applications of CO_(2)electro-reduction products in the transportation industry include theproduction of synthetic fuels,such as methanol and ethanol,which canbe used as alternatives to fossil ***,CO_(2)electro-reductionproducts can be used to produce chemicals and materials used in manyareas in industry,such as plastics and lubricants[1].

关键词： dioxide catalytic chiral

structural stability and magnetism of metastable Ni-Pt intermetallic compounds studied by ab initio calculation

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science China(Technological sciences) 2009年第9期52卷 2681-2687页

作者： che XingLai LI JiaHao DAI Ye LIU BaiXin Advanced Materials Laboratory Department of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

The self-consistent electronic structure calculations were carried out with the accurate frozen-core full-potential projector augmented-wave method on 13 Ni-Pt intermetallic compounds of simple crystalline structures,i.e. A15,D019,D03 and L12 Ni3Pt and NiPt3,and α-NiAs,B1,B2,L2a,and L10 NiPt. The calculations reveal that the L12 Ni3Pt,L10 NiPt and L12 NiPt3 are energetically more stable than their respective competitive structures,indicating that the three structures may be formed in some appropriate conditions. The obtained results match well with the experimental observation or other theory predictions. It is found that there is hybridization between Ni 3d and Pt 5d states,which may significantly affect the structural stability and magnetism of metastable Ni-Pt intermetallic compounds.

关键词： ab initio study magnetism metastable phases

synthesis and Crystal structure of Co(DMsO)_2(H_2O)_2(sCN)_2 with One-dimensional Hydrogen-bonded structure (DMsO = Dimethylsulfoxide)

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Chinese Journal of structural chemistry 2006年第6期25卷 643-646页

作者： WEI Rong-Min che Yun-Xia ZHENG Ji-Min Departmentof Biology chemistry Tianjin Normal University Tianjin 300071 China

The title complex Co（DMsO）2（H2O）2（sCN）2 has been prepared and structurally characterized. It crystallizes in monoclinic, space group P21/n with a= 5.1981（9）, b = 11.944（2）, c = 12.646（2） A,β = 98.686（2）°, V = 776.2（2） A^3, C6H16CoN2O4s4, Mr = 367.38, Z = 2, De = 1.572 g/cm^3, F（000） = 378 and μ（MoKa） = 1.646 mm^-1. The structure was refined to R= 0.0232 and wR = 0.0645 for 1241 observed reflections with I 〉 2σ（I）. In the title complex, each Co（II） atom is octahedrally coordinated by four O atoms from two DMsO ligands and two water molecules as well as two N atoms from sCN^- ions. The title molecules are connected to each other through intermolecular hydrogen bonds to form a 1-D structure extended by eight-membered Co2O4H2 rings.

关键词： dimethylsulfoxide thiocyanate group supramolecule,complex intermolecular hydrogen bond

Two-dimensional coupled mathematical modeling of fluvial processes with intense sediment transport and rapid bed evolution

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science China(Physics,Mechanics & Astronomy) 2008年第9期51卷 1427-1438页

作者： YUE ZhiYuan CAO ZhiXian LI Xin che Tao state Key Laboratory of Water Resources&Hydropower Engineering science Wuhan UniversityWuhan 430072China Cold&Arid Regions Environmental&Engineering Research Institute Chinese Academy of SciencesLanzhou 730000China

Alluvial rivers may experience intense sediment transport and rapid bed evolution under a high flow regime,for which traditional decoupled mathematical river mod-els based on simplified conservation equations are not applicable. A two-dimen-sional coupled mathematical model is presented,which is generally applicable to the fluvial processes with either intense or weak sediment transport. The governing equations of the model comprise the complete shallow water hydrodynamic equa-tions closed with Manning roughness for boundary resistance and empirical rela-tionships for sediment exchange with the erodible bed. The second-order Total-Variation-Diminishing version of the Weighted-Average-Flux method,along with the HLLC approximate Riemann solver,is adapted to solve the governing equations,which can properly resolve shock waves and contact discontinuities. The model is applied to the pilot study of the flooding due to a sudden outburst of a real glacial-lake.

关键词： alluvial river flooding coupled mathematical modeling sediment transport glacier-lake outburst flood