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Abnormal mechanical property evolution induced by heat treatment for a semi-solid forming hypereutectic Al-Fe base alloy

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China Foundry 2015年第3期12卷 208-213页

作者： Run-xia li qing li guo-qing Ren yan-jiao Tong Bao-yi Yu xiao-guang Yuan shenyang University of Technology School of Materials Science and Engineering

In the present study, Al-5.5Fe-4Cu-2Zn-0.4Mg-0.5Mn al oy samples were prepared by electromagnetic stirring and semi-solid forming processing, and then the effects of T6 and T1 heat treatments on the microstructures and mechanical properties of the semi-solid forming samples were investigated. The results indicate that after semi-solid forming, the mechanical properties of the sample improved significantly compared to that of the merely electromagnetically stirred sample. The grains of semi-solid forming alloy became almost fine equiaxed; big long strip-shaped Al3 Fe phases became short rod-like morphology and distributed uniformly in the matrix. However, the mechanical properties of the T6-treated semi-solid forming sample decreased significantly instead of increasing and, with solution temperature rising, the tensile strength of the al oy decreased further. The results of EDS show that after high temperature solid-solution treatment, the Cu element in the semi-solid forming alloy sample is mainly concentrated at the boundaries of the Al3 Fe phases instead of being dissolved in the matrix. At the same time, the grains of the semi-solid forming sample grew slightly after solid-solution treatment. Therefore, the growth of the grains and the accumulation of Cu element at Al3 Fe phase boundaries during solution treatment of the semi-solid forming alloy were the main reasons for the mechanical properties decreasing after T6 treatment. The mechanical properties of the alloy were improved after T1 heat treatment due to aging strengthening phase being precipitated in the matrix.

关键词： Al-Fe base alloys semi-solid forming heat treatment microstructures

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Wet spinning of fiber-shaped flexible Zn-ion batteries toward wearable energy storage

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Journal of Energy Chemistry 2022年第8期31卷 192-200,I0006页

作者： Tingting Gao Guangyuan yan Xin yang qing yan yankuan Tian Jianwei Song Faxue li Xueli wang Jianyong Yu Yiju li shaojun guo Key Laboratory of Textile Science and Technology Ministry of EducationCollege of TextilesDonghua UniversityShanghai 201620China Innovation Center for Textile Science and Technology Donghua UniversityShanghai 201620China School of Materials Science and engineering Peking UniversityBeijing 100871China State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049ShaanxiChina School of Biological and Chemical engineering NingboTech UniversityNingbo 315100ZhejiangChina

High-performance flexible one-dimensional(1D)electrochemical energy storage devices are crucial for the applications of wearable *** much progress on various 1D energy storage devices has been made,challenges involving fabrication cost,scalability,and efficiency ***,a highperformance flexible all-fiber zinc-ion battery(ZIB)is fabricated using a low-cost,scalable,and efficient continuous wet-spinning *** composite inks containing cellulose nanofibers/carbon nanotubes(CNFs/CNTs)binary composite network and either manganese dioxide nanowires(MnO_(2) NWs)or commercial Zn powders are utilized to spinning fiber cathodes and anodes,***_(2) NWs and Zn powders are uniformly dispersed in the interpenetrated CNFs/CNTs fibrous network,leading to homogenous composite inks with an ideal shear-thinning *** obtained fiber electrodes demonstrate favorable uniformity and *** from the well-designed electrodes,the assembled flexible fiber-shaped ZIB delivers a high specific capacity of 281.5 m Ah g^(-1) at 0.25 A g^(-1) and displays excellent cycling stability over 400 ***,the wet-spun fiber-shaped ZIBs achieve ultrahigh gravimetric and volumetric energy densities of 47.3 Wh kg^(-1) and 131.3 m Wh cm^(-3),respectively,based on both cathode and anode and maintain favorable stability even after 4000 bending *** work offers a new concept design of 1D flexible ZIBs that can be potentially incorporated into commercial textiles for wearable and portable electronics.

关键词： Manufacturing Wet spinning Zn ion battery Nanocellulose Fiber

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Electrochemical behavior of different shelled microcapsule composite copper coatings

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International Journal of Minerals,Metallurgy and Materials 2011年第3期18卷 377-384页

作者： Xiu-qing Xu yan-hong guo Wei-ping li li-qun Zhu School of Materials Science and engineering Beihang University Beijing 100191 China

Copper/liquid microcapsule composite coatings with polyvinyl alcohol （PVA）, gelatin or methyl cellulose （MC） as shell materials were prepared by electrodeposition. The influence of shell materials on the corrosion resistance of the composite coatings in 0.1 M H2SO4 was investigated by means of electrochemical techniques, scanning electron microscopy （SEM）, and energy dispersion spectrometry （EDS）. The results show that the participation of microcapsules can enhance the corrosion resistance of the composite coatings compared with the traditional copper layer. Based on the analysis of electrochemical test results, the release ways of microcapsules were deduced. Gelatin and MC as the shell materials of microcapsules are easy to release quickly in the composite coating. On the contrary, the releasing speed of PVA microcapsules is relatively slow due to their characteristics.

关键词： composite coatings shell materials copper microcapsules electrochemical properties corrosion resistance electrodeposition

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Genome-wide scan for selection signatures based on whole-genome re-sequencing in Landrace and Yorkshire pigs

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Journal of Integrative Agriculture 2021年第7期20卷 1898-1906页

作者： wang Kai WU Ping-xian CHEN De-juan ZHOU Jie yanG Xi-di jiang An-an MA Ji-deng TANG Qian-zi xiao Wei-hang jiang yan-zhi ZHU li QIU xiao-tian li Ming-zhou li Xue-wei TANG guo-qing Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province Sichuan Agricultural UniversityChengdu 611130P.R.China College of life Science Sichuan Agricultural UniversityYa'an 625014.P.R.China National Animal Husbandry Service Beijing 100125P.R.China

We performed a genome-wide scan to detect selection signatures that showed evidence of positive selection in the domestication process by re-sequencing the whole genomes of Landrace and Yorkshire *** annotated elements with 13 associated genes were identified using the Z-transformed FST(Z(FST))method,and 208 annotated elements with 140 associated genes were identified using the Z-transformed heterozygosity(ZHp)*** functional analysis and the results of previous studies showed that most of the candidate genes were associated with basic metabolism,disease resistance,cellular processes,and biochemical signals,and several were related to body morphology and *** included PPP3CA,which plays an essential role in the transduction of intracellular Ca2+-mediated signals,and WWTR1,which plays a pivotal role in organ size control and tumor *** results suggest that genes associated with body morphology were subject to selection pressure during domestication,whereas genes involved in basic metabolism and disease resistance were subject to selection during artificial *** findings provide new insights into the potential genetic variation of phenotypic diversity in different pig breeds and will help to better understand the selection effects of modern breeding in Landrace and Yorkshire pigs.

关键词： pig variation whole-genome sequence selection signature phenotypic trait

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Determination of Metamizole Sodium by Cyclic Voltammetry Under Microwave Activation

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Chemical Research in Chinese Universities 2010年第4期26卷 537-540页

作者： li li-jun CHeng Long-jun CAI Zhuo LAN Su-mei guo xiao-fei li yan-qing Department of Biological and Chemical engineering Guangxi University of Technology Liuzhou 545006 P. R. China College of Chemistry and Chemical engineering Guangxi University Nanning 530004 P. R. China

Microwave radiation was applied to the detection of metamizole sodium by cyclic voltammetry. The electrochemical characteristics of metamizole sodium were studied by cyclic voltammetry at GC electrode under microwave radiation and a considerable current enhancement was observed for metamizole sodium in aqueous 0.05 mol/L H2SO4. Under the optional conditions, metamizole sodium was determined in the absence and presence of microwave activation. In the absence of microwave activation cyclic voltammogram of metamizole sodium shows good linear relationship in a concentration range of 8.0×10^-5-1.0×10^-3 mol/L in aqueous 0.05 mol/L H2SO4 with a detection limit of 6.75× 10^-6 mol/L（S/N=3） and the equation of linear regression is Ip=12.973c-0.1905（R^2=0.9996, n=6）; in the presence of 80 W microwave activation cyclic voltammogram of metamizole sodiumin shows good linear relationship in a concentration range of 4.0× 10^-5-1.0×10^-3 mol/L in aqueous 0.05 mol/L H2SO4 with a detection limit of 4,41 × 10^-6 mol/L（S/N=3） and the equation of linear regression is Ip=25.107c-0.1193（R^2=0.9973, n=7）. The current in the presence of 80 W microwave activation increases to about 2 orders of magnitude compared with that in the absence of microwave activation. The proposed method in the presence of microwave activation showed high selectivity and sensitivity, and the sampling of the disposal method is simple. The method was verified by the determination of Metamizole Sodium tablet with satisfactory results.

关键词： Microwave Metamizole sodium Cyclic voltammetry

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Preparation of Al-Hf master alloy by aluminothermic reduction of HfO_(2)

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Rare Metals 2021年第12期40卷 3645-3650页

作者： Hai liu Zhao-Hui Ma Jing-Cun Huang Jian-Dong Zhang guo-qing yan li-Jun wang Division of Rare Metals Metallurgy and Materials GRINM Group Corp.LtdGRIMAT Engineering Institute Co.LtdBeijing 100088China

The Al-Hf alloy was prepared by open aluminothermic reduction of HfO_(2) using CaF_(2) and Na F as the flux. The influence of the slag composition, the amount of aluminum, and the heat energizer was studied detailly to establish optimum conditions for the sufficient recovery of the alloy and the complete slag-alloy separation. The Al-Hf alloy with 40 wt% Hf was obtained by this method, and the maximum recovery was 70.7%. The microstructure of the alloy was observed by scanning electron microscope(SEM). Moreover, X-ray diffraction(XRD) analysis and energy-disperse spectrometry(EDS) were applied to characterize the formation of the phases. The results show that the alloy consists of Al and Al_(3)Hf phases and the oxygen content is about 0.2 wt%.

关键词： Al-Hf master alloy Aluminothermic reduction Hafnium oxide Slag-alloy separation

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Hydrogen permeation resistance and characterization of Si–Al and Si–Zr composite sol oxide coating on surface of zirconium hydride

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Rare Metals 2017年第1期36卷 55-60页

作者： Ming Wu yang Chen Jia-qing Peng guo-qing yan Yu-Pu Sun Jian-Dong Zhang shun-li Zhang li-Jun wang Division of Rare Metals Metallurgy and Materials General Research Institute for Nonferrous Metals Beijing 100088 China

The hydrogen permeation resistance of Si–Zr(SZ) and Si–Al(SA) composite sol oxide coating on zirconium hydride blocks(Zr H) was studied. SZ and SA composite sol were prepared by sol–gel method. SZ and SA composite oxide coatings were prepared on the surface of Zr H(in situ oxidized or not) in turns by dip-coating and heat treatment. Hydrogen permeation of Zr Hwith and without composite oxide coating was *** desorption experiments in thermal vacuum show that hydrogen permeation resistance of SA composite oxide coating is better than that of SZ, to a certain extent,which could decrease hydrogen thermal loss. Experimental results in the working condition show that the SA composite oxide coating can not only prevent hydrogen permeation, but also retard contact and reaction between COand Zr Hmatrix, which could mitigate excessive oxidation of in situ oxide film. Differential scanning calorimetry and thermogravimetry(DSC–TG) analysis was performed to investigate the decomposition behavior of SA and SZ liquid sol in heat treatment process. X-ray diffraction(XRD) and scanning electron microscopy(SEM) analysis were employed to characterize the phase composition,surface and cross-section morphology of the coatings.

关键词： Zirconium hydride Hydrogen permeation resistance Composite oxide coating Si–Zr Si–Al Sol–gel

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On disturbance rejection proportional-integral-differential control with model-free adaptation

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Control Theory and Technology 2023年第1期21卷 34-45页

作者： Zhuo-Yun Nie Gao-Ming li Lai-Cheng yan qing-guo wang Ji-liang Luo School of Information Science and engineering Huaqiao UniversityXiamen 100190FujianChina Institute of Artificial Intelligence and Future Networks Beijing Normal UniversityZhuhai 519087GuangdongChina Guangdong Key Lab of AI and Multi-Modal Data Processing BNU-HKBU United International CollegeZhuhai 519087GuangdongChina

In this paper,an adaptive disturbance-rejection proportional–integral–differential(PID)control method is proposed for a class of nonlinear ***,PID-type criterion is introduced in a model-free adaptive control(MFAC)framework,which gives an optimal control interpretation for PID ***,the design of adaptive disturbance rejection PID is proposed based on this new interpretation to realize controller gain *** to the ingenious integration of active disturbance rejection and adaptive mechanism,the proposed adaptive disturbance rejection PID control scheme exhibits better control performance than MFAC ***,the boundedness of controller gain,the convergence of tracking error and the bounded-input–bounded-output stability are proved for the proposed control ***,the effectiveness of the proposed method is verified by numerical simulation.

关键词： Disturbance rejection PID Data-driven control-Error-driven model Model-free adaptive control

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Numerical simulation of rock-breaking and influence laws of dynamic load parameters during axial-torsional coupled impact drilling with a single PDC cutter

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Petroleum Science 2023年第3期20卷 1806-1827页

作者： yan Xi Hao-Yu wang Chun-qing Zha Jun li Gong-Hui liu Bo-Yun guo Beijing University of Technology Bejing100124China China University of Petroleum-Bejing Beijing102249China China University of Petroleum-Beijing at Karamay KaramayXinjiang834000China University of Louisiana at Lafayett Lafayette70504USA

Axial and torsional impact drilling technology is used to improve the drilling efficiency of hard rock formation in the deep ***,the corresponding theory is not mature,and there are few correlative research reports on the rock-breaking mechanism of axial and torsional coupled impact drilling *** the influence of the impact hammer geometry and movement on the dynamic load parameters(i.e.,wavelength,amplitude,frequency,and phase difference),a numerical model that includes a hard formation and single polycrystalline diamond compact cutter was *** Riedel-Hiermaier-Thoma model,which considers the dynamic damage and strength behavior of rocks,was adopted to analyze the rock damage under axial and torsional impact *** numerical simu-lation results were verified by the experimental *** was found that compared with conventional drilling,the penetration depths of axial,torsional,and axial-torsional coupled impact drilling increased by 31.3%,5.6%,and 34.7%,*** the wavelength and amplitude of the axial impact stress wave improved the penetration *** the bit rotation speed remained unchanged,increasing the frequency in the axial and circumferential directions had little effect on the penetration ***,as the frequency increased,the cutting surface became increasingly smooth,which reduced the occurrence of bit *** the phase difference between the axial and circumfer-ential stress waves was 25%,the penetration depth significantly *** addition,the bit vibration problem can be effectively ***,the adjustment of engineering and tool structure parameters is proposed to optimize the efficiency of the axial-torsional coupled impact drilling tool.

关键词： Axial-torsional coupled impact drilling tool Rock-breaking PDC cutter RHT model

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Abundance analysis of Barium stars

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Chinese Journal of Astronomy and Astrophysics 2009年第4期9卷 431-448页

作者： guo-qing liu yan-Chun liang li-Cai Deng National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

We obtain the chemical abundances of six barium stars and two CH subgiant stars based on the high signal-to-noise ratio and high resolution EcheUe spectra. The neu-Iron capture process elements Y, Zr, Ba, La and Eu show obvious overabundances relative to the Sun, for example, their [Ba/Fe] values are from 0.45 to 1.27. Other elements, including Na, Mg, A1, Si, Ca, Sc, Ti, V, Cr, Mn and Ni, show comparable abundances to the Solar ones, and their [Fe/H] covers a range from -0.40 to 0.21, which means they belong to the Galactic disk. The predictions of the theoretical model of wind accretion for binary systems can explain the observed abundance patterns of the neutron capture process elements in these stars, which means that their overabundant heavy-elements could be caused by accreting the ejecta of AGB stars, the progenitors of present-day white dwarf companions in binary systems.

关键词： stars abundances-stars atmospheres-stars chemically peculiar-stars evolution-binaries spectroscopic

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