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Nano-yttrium-containing precipitates of T6 heat-treated A356.2 alloy when trace yttrium(Y less than 0.100 wt%) added

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Rare Metals 2021年第11期40卷 3279-3288页

作者： Xin-ping hu Qing Wang Henry hu Rui-Xin Li Yang Zhao Zhi-Ming Wang Bing-Rong Zhang School of Mechanical and Automotive Engineering Qilu University of TechnologyJinan 250353China Department of Mechanical University of WindsorAutomotive&MaterialsEngineering Windsor N9B 3P4Canada

To investigate the effect of yttrium(Y) on microstructure refinement and mechanical properties of aluminum alloy A356.2,the different trace contents of Y(0 wt%,0.025 wt%,0.050 wt%,0.075 wt%,or 0.100 wt%)were introduced into the liquid *** alloys were fabricated in a preheated permanent mold,and subsequently treated by a T6 heat *** results of tensile testing indicate that the yield strength(YS),the ultimate tensile strength(UTS) and the elongation(El) of the A356.2 alloy are improved by the Y *** YS dependence on grain size for the test alloys follows the Hall-Petch equation,which gives YS=-354.1+2875.2 d^(-1/2) with a correlation of R^(2)=*** 0.050 wt%Y is added,the optimum values of the YS,UTS and El are achieved after T6 heat *** secondary phases were identified by X-ray diffraction(XRD) which mainly consisted as Si,Mg2 Si and Al3 *** scanning electron microscope(SEM) and energy-dispersive spectrometer(EDS) analyses reveal the presence of the nano-sized Al3 Y particles on the surface of the Si *** A356.2 alloy with the Y addition is strengthened by the dendritic refinement,and the presence of the micron-and nano-sized Al3 Y precipitates.

关键词： Yttrium Microstructures Mechanical properties T6 heat treatment A356.2 alloy

Hardness estimation for covalent crystals using Empirical Electron Theory

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Chinese Science Bulletin 2010年第36期55卷 4197-4202页

作者： LUO XiaoGuang LI Jinping hu ping DONG ShanLiang Center for Composite Materials Harbin Institute of Technology Harbin 150001 China

Covalent electrons substantially determine the intrinsic hardness of inorganic crystals. A hardness model is presented on the basis of the Empirical Electron Theory generated from Pauling’s covalent bond length equation and the bond length difference method. The calculated hardness values of inorganic crystals are in good agreement with experimental and other theoretical values. Covalent bond energy with polarity correction can be used as an intrinsic indicator linking microscopic electronic structure to macroscopic hardness. A simple mathematical processing of bond energy is performed to extend the model to multi-bonding or multi-component systems. It is also found that spatial distribution of covalent bonds has a great influence on the hardness of inorganic crystals.

关键词：经验电子理论硬度指标共价键能无机晶体数学处理模型估计多组分体系差分方法

Effects of Different Molten-salt on the Synthesis of Hexagonal Barium Ferrite

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Chinese Journal of Aeronautics 2006年第B12期19卷 206-209页

作者： WANGJing-ping LIU Ying hu Min ZHANG Mi-lin College of Materials Science and Chemical Engineering Harbin Engineering University Harbin 150001 China

Hexagonal-plate BaFe12O19 nano-particles were prepared by combining the co-precipitation and molten-salt method. The effects of molten-salt NaCl on the products have been compared with those of KCl. The X-ray diffraction analysis, the environment scanning electron microscopy and the vibrating sample magnetometer were used to measure their characteristics. The results show that the mol- ten-salt KCl is helpful to obtain pure phase while the molten-salt NaCl will prompt the crystallinity of particles to increase. It is also found that, given the molten-salt of NaCl and that of KCl of the same quantity, the particles formed are also the same size. The size of particles slightly increases as the quantity of the salt increases. Moreover, the sample prepared under 200% NaCl salt system has magnetization of 71.5 emu/g.

关键词： BaFe12O19 nanoparticles synthesis magnetic property

ThERF1 from Tamarix hispida confers decreased tolerance to oxidative and drought stresses and is regulated by a WRKY protein

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Journal of Forestry Research 2016年第4期27卷 767-772页

作者： Liuqiang Wang Chao Wang Liping Qin ping hu Yucheng Wang State Key Laboratory of Tree Genetics and Breeding(Northeast Forestry University) Harbin 150040 China Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 8300ll China

The ethylene-responsive factor family is one of the largest families of plant-specific transcription factors that are involved in plant development and stress responses. Previously, we demonstrated that the gene Th ERF1,encoding a novel ethylene-responsive factor from Tamarix hispida, negatively modulates abiotic stress tolerance. In the present study, Arabidopsis plants overexpressing Th ERF1 had decreased oxidative tolerance and increased transpirational water loss rate compared with wild-type plants, leading to sensitivity to abiotic stress. Real-time RT-PCR showed that the upstream regulator of Th ERF1,Th WRKY2, is involved in responses to different abiotic stresses. Furthermore, both Th WRKY2 and Th ERF1 shared similar expression patterns in the stems and leaves of *** when exposed to salinity, drought and abscisic acid. Chromatin immunoprecipitation assays further confirmed that Th WRKY2 can directly bind to the promoter of Th ERF1 and regulate its expression. This study revealed the regulatory mechanism of Th ERF1 expression in response to abiotic stresses in T. hispida.

关键词： WRKY drought Tamarix abiotic responsive transgenic encoding Arabidopsis chlorophyll promoter

Synthesis of unsymmetric triphenylene discotic liquid crystals with a semi-fluorinated chain and the influence of fluorophobic effect on mesogenic behavior

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Science China Chemistry 2009年第8期52卷 1244-1252页

作者： YANG GaoFan ZHAO KeQing YU WenHao hu ping WANG BiQin College of Chemistry and Materials Science Sichuan Normal UniversityChengdu 610066China

The fluorophobic effect of the semi-fluorinated chain of discotic molecules efficiently improves the stability of columnar *** symmetric discogens exhibit decreased melting points and wide mesophase ranges.A series of triphenylene derivatives 1,C18H6(OCnH2n+1)4(OMe)(O2CC2H4C6F13),and their hydrocarbon analogues 2,C18H6(OCnH2n+1)4(OMe)(O2CC8H17),n = 4―8,were synthesized for the investigation of the influence of semi-fluorinated peripheral chain and molecular symmetry on *** structures were characterized with 1H NMR and *** mesomorphism was studied with differential scanning calorimetry(DSC) and polarizing optical microscopy(POM).The results showed that all triphenylene derivatives exhibited enantiotropic columnar *** semifluorinated triphenylenes 1a―1e displayed higher melting points and clearing points than their hydrocarbon analogies 2a―*** of them were in columnar mesophase at room temperature.

关键词： discotic liquid crystal triphenylene semi-fluorinated ester chain columnar mesophase fluorophobic effect molecular symmetry

Peridynamic Shell Model Based on Micro-Beam Bond

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Computer Modeling in Engineering & Sciences 2023年第3期134卷 1975-1995页

作者： Guojun Zheng Zhaomin Yan Yang Xia ping hu Guozhe Shen School of Automotive Engineering Dalian University of TechnologyDalian116024China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian116024China

Peridynamics(PD)is a non-localmechanics theory that overcomes the limitations of classical continuummechanics(CCM)in predicting the initiation and propagation of ***,the calculation efficiency of PDmodels is generally lower than that of the traditional finite elementmethod(FEM).Structural idealization can greatly improve the calculation efficiency of PD models for complex *** study presents a PD shell model based on the micro-beam bond via the homogenization ***,the deformations of each endpoint of themicro-beam bond are calculated through the interpolation ***,the micro-potential energy of the axial,torsional,and bending deformations of the bond can be established from the deformations of ***,the micro moduli of the shellmodel can be obtained via the equivalence principle of strain energy density(SED).In addition,a new fracture criterion based on the SED of the micro-beam bond is adopted for crack *** examples of crack propagation are provided,and the results demonstrate the effectiveness of the proposed PD shell model.

关键词： Peridynamics shell micro-beam bond interpolation method crack propagation homogenization

Gaussian-curvature-derived invariants for isometry

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Science China(Information Sciences) 2013年第9期56卷 219-230页

作者： CAO WeiGuo hu ping LIU YuJie GONG Ming LI hua Institute of Computing Technology Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences School of Computer Science and Communication Engineering China University of Petroleum

Surface deformations without tearing or stretching, preserving the intrinsic properties, are called isometries. This paper presents a new definition of Gaussian curvature moments (GCMs) by the integral of n power of Gaussian curvature. Then a series of moment invariants, called Gaussian curvature moment invariants (GCMIs), are derived via GCMs. These moment invariants share many good properties under rigid transformations and isometric non-rigid transformations, and Gaussian-Bonnet theorem is a special case of GCMI. GCMIs are invariant under isometry and scaling transformations. We construct an invariant vector as a descriptor for a surface via GCMIs, and a modified χ2 distance is defined as a measure of similarity. Finally, experiments show that it is a reliable descriptor for isometric non-rigid shape.

关键词： rigid object non-rigid object isometry scale Gaussian curvature moment moment invariant

Data-Driven Structural Topology Optimization Method Using Conditional Wasserstein Generative Adversarial Networks with Gradient Penalty

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Computer Modeling in Engineering & Sciences 2024年第12期141卷 2065-2085页

作者： Qingrong Zeng Xiaochen Liu Xuefeng Zhu Xiangkui Zhang ping hu School of Automotive Engineering Dalian University of TechnologyDalian116024China

Traditional topology optimization methods often suffer from the“dimension curse”problem,wherein the com-putation time increases exponentially with the degrees of freedom in the background *** this challenge,we introduce a real-time topology optimization approach leveraging Conditional Generative Adversarial Networks with Gradient Penalty(CGAN-GP).This innovative method allows for nearly instantaneous prediction of optimized *** a specific boundary condition,the network can produce a unique optimized structure in a one-to-one *** process begins by establishing a dataset using simulation data generated through the Solid Isotropic Material with Penalization(SIMP)***,we design a conditional generative adversarial network and train it to generate optimized *** further enhance the quality of the optimized structures produced by CGAN-GP,we incorporate *** augmentation results in sharper topologies,yielding structures with enhanced clarity,de-blurring,and edge *** proposed method yields a significant reduction in computational time when compared to traditional topology optimization algorithms,all while maintaining an impressive accuracy rate of up to 85%,as demonstrated through numerical examples.

关键词： Real-time topology optimization conditional generative adversarial networks dimension curse CMES,2024,vol.141,no.3

Application of Microbiome in Forensics

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Genomics, Proteomics & Bioinformatics 2023年第1期21卷 97-107页

作者： Jun Zhang Wenli Liu Halimureti Simayijiang ping hu Jiangwei Yan School of Forensic Medicine Shanxi Medical UniversityTaiyuan 030001China Beijing Center for Physical and Chemical Analysis Beijing 100089China Key Laboratory of Environment and Health(huST) Ministry of Education&Ministry of Environmental Protectionand State Key Laboratory of Environmental Health(Incubation)School of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430074China

Recent advances in next-generation sequencing technologies and improvements in bioinformatics have expanded the scope of microbiome analysis as a forensic *** research is concerned with the study of the compositional profile and diversity of microbial flora as well as the interactions between microbes,hosts,and the *** has opened up many new possibilities for forensic *** this review,we discuss various applications of microbiome in forensics,including identification of individuals,geolocation inference,and post-mortem interval(PMI)estimation.

关键词： Microbiome Forensics Next-generation sequencing Bioinformatics Application