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Propagation effect of gravitational wave on detector response

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Science China(Physics,Mechanics & Astronomy) 2016年第10期59卷 81-84页

作者： Zhe Chang Chao-Guang Huang zhi-Chao zhao Institute of High Energy Physics and Theoretical Physics Center for Science Facilities Chinese Academy of Sciences

Dear Editors,The detection of gravitational waves（GW）in the event GW150914 by the two advanced detectors of the Laser Interferometer Gravitational-wave Observatory（LIGO）[1]opens a new era for the direct detection of GW[2],searching black hole coalescence[3]and‘heavy’black holes with more than25 solar mass[4],test of general relativity[5],understanding the astrophysical environment of black hole formation[6],*** one words,

关键词：探测器引力波传播效应广义相对论激光干涉直接检测太阳质量物理环境

Lithium intercalation mechanism for β-SnSb in Sn-Sb thin films

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International Journal of Minerals,Metallurgy and Materials 2011年第2期18卷 216-222页

作者： Qiang Ru Qin Tian She-jun Hu Ling-zhi zhao Laboratory of Quantum Information Technology School of Physics and Telecommunication Engineering South China Normal University Guangzhou 510006 China Department of Chemistry South China Normal University Guangzhou 510006 China

Based on the first-principles plane wave pseudo-potential method, the electronic structure and electrochemical performance of LixSn4Sb4 （x=2, 4, 6, and 8） and LixSn12-xSb4 （x=9, 10, 11, and 12） phases were calculated. A Sn-Sb thin film on a Cu foil was also prepared by radio frequency magnetron sputtering. The surface morphology, composition, and lithium intercalation/extraction behavior of the fabricated film were characterized by scanning electron microscopy （SEM）, X-ray diffraction （XRD） and cyclic voltammetry （CV）. Lithium atoms can easily insert into and extract out of the β-SnSb cell due to the low lithium intercalation formation energy. It is found that lithium atoms first occupy the interstitial sites, and then Sn atoms at the lattice positions are replaced by excessive lithium. The dissociative Sn atoms continue to produce different Li-Sn phases, which will affect the electrode stability and lead to the undesirable effect due to their large volume expansion ratio. The calculated lithium intercalation potential is stable at about 0.7 V, which is consistent with the experimental result.

关键词： lithium batteries first-principles Sn-Sb alloys electronic structure thin films

PREPARATION AND SECOND-ORDER OPTICAL NONLINEARITY OF NOVEL PHENOXYSILICON NETWORKS BY SOL-GEL PROCESS

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Chinese Journal of Polymer Science 2001年第1期19卷 39-44页

作者： Xiao Huang Jian Wang Ling-zhi Zhang zhi-gang Cai zhao-xi Lianga Institute of Polymer Science Zhongshan University Guangzhou 510275 China Institute of Polymer Science Zhongshan University Guangzhou 510275 China Institute of Polymer Science Zhongshan University Guangzhou 510275 China State Key Lab of Ultrafast Laser Spectroscopy Zhongshan University Guangzhou 510275 China Institute of Polymer Science Zhongshan University Guangzhou 510275 China

Four phenoxysilicon networks for nonlinear optical (NLO) applications were designed and prepared by an extended sol-gel process without additional H2O and catalyst. All poled polymer network films possess high second-order nonlinear optical coefficients (d(33)) Of 10(-7)similar to 10(-8) esu. The investigation of NLO temporal stability at room temperature and elevated temperature (120 degreesC) indicated that these films exhibit high d(33) stability because the orientation of the chromophores are locked in the phenoxysilicon organic/inorganic networks.

关键词： phenoxysilicon networks sol-gel process azobenzene chromophore stilbene chromophore second order optical nonlinearity

Prediction of hot-rolled strip crown based on Boruta and extremely randomized trees algorithms

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Journal of Iron and Steel Research International 2023年第5期30卷 1022-1031页

作者： Li Wang Song-lin He zhi-ting zhao Xian-du Zhang School of Mechanical and Power Engineering Shenyang University of Chemical TechnologyShenyang 110142LiaoningChina

The quality of hot-rolled steel strip is directly affected by the strip *** machine learning models have shown limitations in accurately predicting the strip crown,particularly when dealing with imbalanced *** limitation results in poor production quality and efficiency,leading to increased production ***,a novel strip crown prediction model that uses the Boruta and extremely randomized trees(Boruta-ERT)algorithms to address this issue was *** improve the accuracy of our model,we utilized the synthetic minority over-sampling technique to balance the imbalance data *** Boruta-ERT prediction model was then used to select features and predict the strip *** the 2160 mm hot rolling production lines of a steel plant serving as the research object,the experimental results showed that 97.01% of prediction data have an absolute error of less than 8 *** level of accuracy met the control requirements for strip crown and demonstrated significant benefits for the improvement in production quality of steel strip.

关键词： Hot-rolled strip Data improvement Strip crown Feature selection Boruta algorithm Extremely randomized trees algorithm

Scalable synthesis of hcp ruthenium-molybdenum nanoalloy as a robust bifunctional electrocatalyst for hydrogen evolution/oxidation

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Journal of Energy Chemistry 2022年第9期31卷 176-185,I0006页

作者： Zhen Zhang Haijun Liu Liwen Ni zhi-Liang zhao Hui Li School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001HeilongjiangChina Department of Materials Science and Engineering Shenzhen Key Laboratory of Hydrogen EnergySouthern University of Science and TechnologyShenzhen 518055GuangdongChina Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055GuangdongChina

The hydrogen evolution reaction(HER)is the cathodic process of water splitting,and its reverse,the hydrogen oxidation reaction(HOR),is the anodic process of an H-Ofuel cell;both play important roles in the development of hydrogen *** rational design and scalable fabrication of low-cost and efficient bifunctional catalysts for the HER/HOR are highly ***,ultrasmall Mo-Ru nanoalloy(Mo_(0.5)Ru_(3)and Mo_(0.5)Ru_(3))particles uniformly distributed on mesoporous carbon(MPC)were successfully synthesized by a simple method that is easy to scale up for mass *** the incorporation of Mo atoms,the as-prepared Mo_(0.5)Ru_(3)and Mo_(0.5)Ru_(3)nanoalloys maintain a hexagonal-close-packed crystal *** acidic media,Mo_(0.5)Ru_(3)exhibits excellent Pt-like HER and HOR activity,as well as good *** functional theory(DFT)calculations reveal that the H adsorption free energy(ΔG)on the Mo_(0.5)Ru_(3)(001)surface(-0.09 eV)is much closer to zero than that of metallic Ru(-0.22 eV),which contributes to the enhanced catalytic *** alkaline media,Mo_(0.5)Ru_(3)also presents outstanding HER and HOR activity,even significantly outperforming Pt/*** DFT results confirm that optimal binding energies with H*and OH*intermediate species,and low energy barriers in the water dissociation and formation steps,efficiently accelerate the alkaline HER/HOR kinetics of Mo_(0.5)Ru_(3).This study provides a new avenue for the scalable fabrication of high-efficiency bifunctional electrocatalysts for the HER and HOR in both acidic and alkaline media.

关键词： Hydrogen evolution reaction Hydrogen oxidation reaction Ruthenium Water splitting Fuel cell

Early Stage Solvation of Protonated Methanol by Carbon Dioxide

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Chinese Journal of Chemical Physics 2015年第4期28卷 -页

作者： zhi zhao Xiang-tao Kong Xin Lei Bing-bing Zhang Ji-jun zhao Ling Jiang Key Laboratory of Materials Modification by Laser Ion and Electron Beams Dalian University of Technology Ministry of Education Dalian 116024 ChinaState Key Laboratory of Molecular Reaction Dynamics Collaborative Innovation Center of Chemistry for Energy and Materials Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China State Key Laboratory of Molecular Reaction Dynamics Collaborative Innovation Center of Chemistry for Energy and Materials Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China State Key Laboratory of Molecular Reaction Dynamics Collaborative Innovation Center of Chemistry for Energy and Materials Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 ChinaState Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116024 China Key Laboratory of Materials Modification by Laser Ion and Electron Beams Dalian University of Technology Ministry of Education Dalian 116024 China

The solvation of protonated methanol by carbon dioxide has been studied via a cluster model. Quantum chemical calculations of the H+(CH3OH)(CO2)n (n=1–7) clusters indicate that the first solvation shell of the OH groups is completed at n=3 or 4. Besides hydrogen-bond interaction, the CCO2 ? OCO2intermolecular interaction is also responsible for the stabilization of the larger clusters. The transfer of the proton from methanol onto CO2 with the formation of the OCOH+ moiety might be unfavorable in the early stage of solvation process. Simulated IR spectra reveal that vibrational frequencies of free O–H stretching, hydrogen-bonded O–H stretching, and O–C–O stretching of CO2 unit afford the sensitive probe for exploring the solvation of protonated methanol by carbon dioxide. IR spectra for the H+(CH3OH)(CO2)n (n=1–7) clusters could be readily measured by the infrared photodissociation technique and thus provide useful information for the understanding of solvation processes.

关键词： Methanol Carbon dioxide Solvation Infrared photodissociation spectroscopy Quantum chemical calculation

Errata to “On Self-mapping Degrees of S^3-geometry Manifolds”

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Acta Mathematica Sinica,English Series 2019年第12期35卷 1979-1982页

作者： Xiao Ming DU Xue zhi zhao School of Mathematics South China University of TechnologyGangzhou 510640P.R.China Department of Mathematics Capital Normal UniversityBeijing 100048P.R.China

The set of self-mapping degrees of S^3-geometry 3-manifolds in[2]have some mistakes when the fundamental group of the 3-manifold is D4n^*,O48^*,D'n·2q or T'8·*** we need to make this *** self-mapping degrees of all closed and oriented 3-manifolds are listed in[1]and[5].The table of spherical case in[5]is mostly quoted from[2].The results in[5]which do not involve the corrections made here still *** results in[5]involving the corrections made here should be also changed.

关键词： Mapping degree spherical manifold

Mechanical properties and characteristics of nanometer-sized precipitates in hot-rolled low-carbon ferritic steel

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International Journal of Minerals,Metallurgy and Materials 2014年第3期21卷 266-272页

作者： Xiao-pei Wang Ai-min zhao Zheng-zhi zhao Yao Huang Liang Li Qing He Engineering Research Institute University of Science and Technology Beijing

The microstructures and properties of hot-rolled low-carbon ferritic steel have been investigated by optical microscopy, field-emission scanning electron microscopy, transmission electron microscopy, and tensile tests after isothermal transformation from 600°C to 700°C for 60 min. It is found that the strength of the steel decreases with the increment of isothermal temperature, whereas the hole expansion ratio and the fraction of high-angle grain boundaries increase. A large amount of nanometer-sized carbides were homogeneously distributed throughout the material, and fine（Ti, Mo）C precipitates have a significant precipitation strengthening effect on the ferrite phase because of their high density. The nanometer-sized carbides have a lattice parameter of 0.411-0.431 nm. After isothermal transformation at 650°C for 60 min, the ferrite phase can be strengthened above 300 MPa by precipitation strengthening according to the Ashby-Orowan mechanism.

关键词： ferritic steel nanoparticles mechanical properties carbides precipitation strengthening

Effect of microstructure evolution on Luders strain and tensile properties in an intercritical annealing medium-Mn steel

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Journal of Iron and Steel Research International 2021年第6期28卷 762-772页

作者： Shuai Wang Wei-jian Chen Zheng-zhi zhao Xiao-long zhao Xiao-yang Luo Qiang Wang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China Beijing Laboratory for Modern Transportation Advanced Metal Materials and Processing Technology University of Science and Technology BeijingBeijing 100083China Carbon Steel and Thin Slab Factory of Hongxing Iron and Steel Co. Ltd.Jiuquan Iron and Steel GroupJiayuguan 735100GansuChina

The influence of microstructural characteristics on Lu¨ders strain and mechanical properties was explored by means of altering thermo-mechanical circumstances in an intercritical annealing(IA)medium-Mn Fe-11Mn-0.09C-0.25Si(wt.%)*** IA of cold-rolled samples with severe plastic deformation,exclusively equiaxed dual phases were obtained because of active recovery and *** equiaxed austenite(gamma E)with a larger size and inadequate chemical concentration was more readily transformed into martensite,and subsequent transformation-induced plasticity(TRIP)effect was triggered actively at relatively higher IA temperature,lessening localized *** addition,grown-in dislocations were prone to multiply and migrate around a broad mean free path for coarser equiaxed ferrite(alpha E)due to weakening dynamic recovery;therefore,it was the ensuing increased mobility of dislocations instead of reserving plentiful initial dislocation density that facilitated the propagation velocity of Luders bands and the accumulation of work *** contrast,the bimodal-grained microstructure with lath-like and equiaxed austenite(gamma L+gamma E)satisfactorily contributed to a smaller yield point elongation(YPE)without compromise of comprehensive mechanical properties on the grounds that austenitic gradient stability gave rise to discontinuous but sustainable TRIP effect and incremental work ***,Luders strain is closely related to the absence of work hardening in the region which yields *** follows that the decreased stability of retained austenite,favorable mobility of dislocations and the bimodal-grained structure all prominently make up for the insufficiency of work hardening,thereof resulting in a limited YPE.

关键词： Luders strain Medium-Mn steel Work hardening Dislocation Mechanical property