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Journal of Iron and Steel Research International 2022年第5期29卷 859-865页

作者： Wen-hao Gong De-hong lu Guang-yu He wei Ma Qing-hua Yan Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming650093China

The effect of the volume fraction of 3D-metal matrix composites(MMC)framework on the compressive properties of 3D interpenetrating hierarchical ZrO_(2)-toughened Al_(2)O_(3)particle(ZTAp)/40Cr steel composites was *** results showed that the compressive properties of the material tended to decrease as the volume fraction of 3D-MMC framework *** composite with 35 vol.%3D-MMC had a yield strength of 1455.2 MPa and compressive strength of 1612.8 MPa,which occurred at a strain value of 5.6%.Compared to the homogeneously dispersed composite material,the composite with 35 vol.%3D-MMC had a 144.7%higher yield strength,which occurred at a 20%higher *** analysis of the cracks inside the material revealed that the crack was hindered and deflected by the matrix during propagation,which lengthened the crack propagation path and consumed more energy,thus leading to *** results indicated that 3D interpenetrating hierarchical structure had a strengthening and toughening effect on ZTAp/40Cr composites.

关键词： Architectured composite Metal matrix composite ZrO_(2)-toughened Al_(2)O_(3) Compressive property Hierarchical composite

Nuclear charge radius predictions by kernel ridge regression with odd-even effects

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Nuclear Science and Techniques 2024年第2期35卷 94-102页

作者： lu Tang Zhen-hua Zhang Mathematics and Physics Department North China Electric Power UniversityBeijing 102206China Hebei Key Laboratory of Physics and Energy Technology North China Electric Power UniversityBaoding 071000China

The extended kernel ridge regression(EKRR)method with odd-even effects was adopted to improve the description of the nuclear charge radius using five commonly used nuclear *** are:(i)the isospin-dependent A^(1∕3) formula,(ii)relativistic continuum Hartree-Bogoliubov(RCHB)theory,(iii)Hartree-Fock-Bogoliubov(HFB)model HFB25,(iv)the weizsacker-Skyrme(WS)model WS*,and(v)HFB25**** the last two models,the charge radii were calculated using a five-parameter formula with the nuclear shell corrections and deformations obtained from the WS and HFB25 models,*** each model,the resultant root-mean-square deviation for the 1014 nuclei with proton number Z≥8 can be significantly reduced to 0.009-0.013 fm after considering the modification with the EKRR *** best among them was the RCHB model,with a root-mean-square deviation of 0.0092 *** extrapolation abilities of the KRR and EKRR methods for the neutron-rich region were examined,and it was found that after considering the odd-even effects,the extrapolation power was improved compared with that of the original KRR *** strong odd-even staggering of nuclear charge radii of Ca and Cu isotopes and the abrupt kinks across the neutron N=126 and 82 shell closures were also calculated and could be reproduced quite well by calculations using the EKRR method.

关键词： Nuclear charge radius Machine learning Kernel ridge regression method

Porousβ-FeOOH nanotube stabilizing Au single atom for highefficiency nitrogen fixation

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Nano Research 2022年第4期15卷 3026-3033页

作者： Hao Sun hua-Qing Yin Wenxiong Shi lu-lu Yang Xiang-wei Guo Hong Lin Jiangwei Zhang Tong-Bu lu Zhi-Ming Zhang Institute for New Energy Materials&Low Carbon Technologies School of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China Dalian National Laboratory for Clean Energy&State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of Sciences(CAS)Dalian 116023China

Electrochemical nitrogen reduction reaction(NRR)under ambient conditions is highly desirable to achieve sustainable ammonia(NH3)production via an alternative carbon free ***-atom catalysts(SACs)with super high atomic utilization and catalytic efficiency exhibit great potential for ***,a high-performance NRR SAC is facilely prepared via a simple deposition method to anchor Au single atoms onto porousβ-FeOOH *** resulting Au-SA/FeOOH can efficiently drive NRR under ambient conditions,and the NH3 yield reaches as high as 2,860μg·h^(-1)·mg_(Au)^(-1)at-0.4 V *** hydrogen electrode(RHE)with 14.2%faradaic efficiency,much superior to those of all the reported Au-based *** investigations demonstrate that the synergy of much enhanced N_(2)adsorption,directional electron export,and mass transfer ability in Au-SA/FeOOH greatly contributes to the superior NRR *** work highlights a new insight into the design of high efficient NRR electrocatalysts by combination of porous metal oxide matrix and highly active single-atom sites.

关键词： dinitrogen(N_(2))reduction electrocatalysis single atom porous iron oxyhydroxide

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稀土对硬质合金线胀系数及粘结相形态的影响

稀有金属与硬质合金 1999年第3期27卷 30-33页

作者：刘红卫陈康华吕海波粉末冶金国家重点实验室湖南长沙410083

主要研究添加稀土后的硬质合金线胀系数的变化规律、粘结相中面心立方 β Ｃｏ的含量（质量分数）及其钴相晶格常数的变化规律。

关键词：稀土硬质合金线胀系数粘结相

Bayesian Regularized Regression Based on Composite Quantile Method

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Acta Mathematicae Applicatae Sinica 2016年第2期32卷 495-512页

作者： wei-hua ZHAO Ri-quan ZHANG Ya-zhao lu Ji-cai LIU School of Statistics East China Normal UniversityShanghai 200241China School of Science NanTong UniversityNanTong 226007China Department of Mathematics Shanxi Datong UniversityDatong 037009China

Recently, variable selection based on penalized regression methods has received a great deal of attention, mostly through frequentist＇s models. This paper investigates regularization regression from Bayesian perspective. Our new method extends the Bayesian Lasso regression （Park and Casella, 2008） through replacing the least square loss and Lasso penalty by composite quantile loss function and adaptive Lasso penalty, which allows different penalization parameters for different regression coefficients. Based on the Bayesian hierarchical model framework, an efficient Gibbs sampler is derived to simulate the parameters from posterior distributions. Furthermore, we study the Bayesian composite quantile regression with adaptive group Lasso penalty. The distinguishing characteristic of the newly proposed method is completely data adaptive without requiring prior knowledge of the error distribution. Extensive simulations and two real data examples are used to examine the good performance of the proposed method. All results confirm that our novel method has both robustness and high efficiency and often outperforms other approaches.

关键词： composite quantile regression variable selection Lasso adaptive Lasso, Gibbs sampler

Multi-spectral remote sensing image enhancement method based on PCA and IHS transformations

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第6期12卷 453-460页

作者： Shan-long lu Le-jun ZOU Xiao-hua SHEN Wen-yuan WU wei ZHANG Department of Earth Sciences Zhejiang University Hangzhou 310027 China Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China China A ero Geophysical Survey & Remote Sensing Center for Land and Resources Beijing 100083 China

This paper introduces a new enhancement method for multi-spectral satellite remote sensing imagery,based on principal component analysis(PCA) and intensity-hue-saturation(IHS) *** PCA and the IHS transformations are used to separate the spatial information of the multi-spectral image into the first principal component and the intensity component,*** enhanced image is obtained by replacing the intensity component of the IHS transformation with the first principal component of the PCA transformation,and undertaking the inverse IHS *** objective of the proposed method is to make greater use of the spatial and spectral information contained in the original multi-spectral *** the basis of the visual and statistical analysis results of the experimental study,we can conclude that the proposed method is an ideal new way for multi-spectral image quality enhancement with little color *** has potential advantages in image mapping optimization,object recognition,and weak information sharpening.

关键词： Remote sensing Principal component analysis(PCA) Intensity-hue-saturation(IHS) transformation Image enhancement Spatial information Spectral information

A family of high-temperature ferromagnetic monolayers with locked spin-dichroism-mobility anisotropy: MnNX and CrCX(X=Cl,Br,I;C=S,Se,Te)

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Science Bulletin 2019年第5期64卷 293-300页

作者： Cong Wang Xieyu Zhou Linwei Zhou Ning-hua Tong Zhong-Yi lu wei Ji Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-Nano Devices Department of Physics Renmin University of China

Two-dimensional magnets have received increasing attention since Cr_2Ge_2Te_6 and CrI_3 were experimentally exfoliated and measured in 2017. Although layered ferromagnetic metals were demonstrated at room temperature, a layered ferromagnetic semiconductor with high Curie temperature(Tc) is yet to be unveiled. Here, we theoretically predicted a family of high Tcferromagnetic monolayers, namely MnNX and CrCX(X = Cl, Br and I; C = S, Se and Te). Their Tcvalues were predicted from over 100 K to near 500 K with Monte Carlo simulations using an anisotropic Heisenberg model. Eight members among them show semiconducting bandgaps varying from roughly 0.23 to 1.85 eV. These semiconducting monolayers also show extremely large anisotropy, i.e. ～10~1 for effective masses and ～10~2 for carrier mobilities, along the two in-plane lattice directions of these layers. Additional orbital anisotropy leads to a spin-locked linear dichroism, in different from previously known circular and linear dichroisms in layered *** with the mobility anisotropy, it offers a spin-, dichroism-and mobility-anisotropy *** results manifest the potential of this 2D family for both fundamental research and high performance spin-dependent electronic and optoelectronic devices.

关键词： Two-dimentional materials First-principles calculation Strong mobility anisotropy Spin-locked linear dichroism High-temperature ferromagnets Direct bandgap semic on ductor

Effects of Heat Softening on Initiation of Landslides

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Journal of Mountain Science 2014年第6期11卷 1571-1578页

作者： XIONG Chuan-xiang lu Xiao-bing huaNG wei-da WANG Cheng-hua School of Environment and Resources Fuzhou University Fujian Provincial Key Laboratory of Remote Sensing of Soil Erosion and Disaster Protection Institute of Mechanics Chinese Academy of Sciences Fujian Academy of Building Research Institute of Mountain Hazards and Environment Chinese Academy of Sciences

Effects of heat softening on the initiation of slide surface(shear banding) in clayey slopes during fast deformation were *** equations considering heat,pore pressure and mechanical movement were *** perturbation method,the instability condition of localized zone(*** for initiation of shear banding) for thermal related soils,such as clayey slope,was *** is shown that slide surface initiates once the thermal-softening effects overcome the strain-hardening effects whether it is adiabatic or *** strain hardening effects,strain rate hardening obviously plays a role in initiation of shear *** initiating process,heat is trapped inside the shear band,which leads rapidly to a pore pressure increase and fast loss of *** localized shear strain is concentrated in a narrow zone with a width of several centimeters at most and increases *** zone forms the sliding *** can increase more than 2?C,pore pressure can increase 160% in about 0.1s inside this *** changes cause the fast decrease in friction-coefficient by about 36% over the initial *** is how shear band initiated and developed in clayey slopes.

关键词： Landslide Thermo-effect Slide surface Initiation

Synthesis,Characterization and Application of Some Axially Chiral Binaphthyl Phosphoric Acids in Asymmetric Mannich Reaction

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Chinese Journal of Chemistry 2015年第5期33卷 601-609页

作者： Yuanyong Yao hua Shu Bangcheng Tang Shixue Chen Zhongying lu wei Xue Institute of Material and Chemical Engineering Tongren UniversityTongrenGuizhou 554300China Center for Research and Development of Fine Chemicals Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityGuiyangGuizhou 550025China

Two novel chiral Brønsted acids 3b and 3c were prepared without involving the complexity of Suzuki *** 3c bearing two additional hydroxyl groups at 3 and 3'positions of axially chiral 1,1-binaphthalene-2,2'-diol phosphoric acid was applied in a model Mannich reaction to affordβ-amino ester in high yield(92%)and enantiomeric excess(91%)at low reacting temperature of−40℃.In addition,thoseβ-amino ester derivatives with high yields and excellent enatioselectivities were obtained in the presence of catalyst 3c under the above condition.

关键词： asymmetric organocatalysis Brønsted acid Mannich reaction binaphthyl phosphoric acids

Acid-base cooperativity of heterogeneous catalyst containing acidic framework and sterically hindered base for aldol condensation

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Chinese Chemical Letters 2009年第9期20卷 1051-1054页

作者： hua Li Shu Tao Xu Xiao Bing lu wei Ping Zhang State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012 China State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China

A bifunctional heterogeneous catalyst containing two mutually incompatible acidic and basic sites, which exhibits cooperative catalytic behavior in the aldol condensation of acetone and various aldehydes, was synthesized by postgrafting of 1,5,7- triazabicyclo[4.4.0] dec-5-ene （TBD, a sterically hindered organic base） onto AI-MCM-41 molecular sieve. 2009 Xiao Bing lu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Bifunctional catalyst Acid-base cooperative catalysis Mesoporous material Aldol reaction