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Phase field simulation of the 180°domain-switching process in PbTiO_3 single crystal under an antiparallel electric field

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International Journal of Minerals,Metallurgy and Materials 2010年第4期17卷 494-499页

作者： Ping-li liu Wu-Yang Chu li-jie qiao Corrosion and Protection Center Key Laboratory of Environmental Fracture University of Science and Technology Beijing Beijing 100083 China

The process of 180°domain switching in PbTiO_3 single crystal under an antiparallel electric field was investigated by the three-dimensional phase field simulation,especially the effect of electric field on the type and duration of domain *** is found that the polarization reversal of domains takes place under an antiparallel electric field in PbTiO_3 single *** results of the phase field simulation indicate that there is only 90°domain switching under a weak electric *** the rise of the electric field,180°domain switching *** the electric field is strengthened further,90°domain switching disappears and the duration of domain switching is shortened.

关键词： phase field simulation ferroelectric materials electric field domain switching

Characterization of a Y-type hexagonal ferrite-based frequency tunable microwave absorber

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International Journal of Minerals,Metallurgy and Materials 2012年第5期19卷 453-456页

作者： Fang Xu Yang Bai Kai Jiang li-jie qiao College of Chemistry and Environmental Science Henan Normal University Xinxiang 453007 China Engineering Technology Research Center of Motive Power and Key Materials of Henan Province Xinxiang 453007 China Corrosion and Protection Center The Key Laboratory of the Ministry of Education of China for Environmental Fracture University of Science and Technology BeijingBeijing 100083 China

A Y-type hexaferrite rod with the composition of Ba2COl.8Cuo.2Fe12022 was presented as an absorbing material with high absorb- anee. Its high absorbance and wide absorption band result from ferromagnetic resonance （FMR） that is self-biased by strong shape and mag- netocrystaUine anisotropy fields. Around the FMR frequency the specimen of the ferrite rods exhibits very high absorbance and the FMR frequency can be tuned by the rod dimension. In addition to the high absorbance and the wide tunable absorption band, the microwave ab- sorber has another advantage of light weight due to the use of the ferrite rods instead of ferrite slabs.

关键词： hexagonal ferfite microwave materials microwave absorbers cobalt compounds ferromagnetic resonance

Single-negative properties of Ba_2Co_(1.8)Cu_(0.2)Fe_(12)O_(22) and Ba_3Co_2Fe_(23.4)Zn_(0.6)O_(41) hexagonal ferrites

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International Journal of Minerals,Metallurgy and Materials 2011年第6期18卷 683-685页

作者： Fang Xu Yang Bai Kai Jiang li-jie qiao College of Chemistry and Environmental Science Henan Normal University Xinxiang 453007 China Corrosion and Protection Center Key Laboratory of Environmental Fracture （Ministry of Education） University of Science and Technology Beijing Beijing 100083 China

The electromagnetic properties of Ba2Co1.8Cu0.2Fe12O22 （Co2Y） and Ba3Co2Fe23.4Zn0.6O41 （Co2Z） were studied by measuring microwave scattering *** the transmission spectra of Ba2Co1.8Cu0.2Fe12O22,a forbidden band emerges due to ferromagnetic resonance,and the permeability will turn to negative in the vicinity of the ferromagnetic resonance *** the complex permittivity spectra of Ba3Co2Fe23.4Zn0.6O41,the negative permittivity can be obtained due to dielectric ***,Co2Y and Co2Z can be used to construct left-handed materials possessing negative permeability and negative permittivity simultaneously.

关键词： left-handed materials hexagonal ferrite ferromagnetic materials permeability permittivity resonance

Effect of in-situ nanoparticles on the mechanical properties and hydrogen embrittlement of high-strength steel

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International Journal of Minerals,Metallurgy and Materials 2021年第4期28卷 644-656页

作者： Rong-jian Shi Zi-dong Wang li-jie qiao Xiao-lu Pang Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Corrosion and Protection Center University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

We investigated the critical influence of in-situ nanoparticles on the mechanical properties and hydrogen embrittlement(HE)of high-strength *** results reveal that the mechanical strength and elongation of quenched and tempered steel(919 MPa yield strength,17.11%elongation)are greater than those of hot-rolled steel(690 MPa yield strength,16.81%elongation)due to the strengthening effect of insitu Ti_(3)O_(5)–Nb(C,N)*** addition,the HE susceptibility is substantially mitigated to 55.52%,approximately 30%lower than that of steels without in-situ nanoparticles(84.04%),which we attribute to the heterogeneous nucleation of the Ti_(3)O_5 nanoparticles increasing the density of the *** with hard TiN inclusions,the spherical and soft Al_(2)O_(3)–MnS core–shell inclusions that nucleate on in-situ Al_(2)O_(3) particles could also suppress ***-situ nanoparticles generated by the regional trace-element supply have strong potential for the development of high-strength and hydrogen-resistant steels.

关键词： in-situ nanoparticles hydrogen embrittlement high-strength steel mechanical properties microstructure

Atomic modeling for the initial stage of chromium passivation

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International Journal of Minerals,Metallurgy and Materials 2019年第6期26卷 732-739页

作者： li-nan Zhang Xi-lin Xiong Yu Yan Ke-wei Gao li-jie qiao Yan-jing Su Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Corrosion and Protection Center Key Laboratory for Environmental Fracture(MOE)University of Science and Technology BeijingBeijing 100083China SUNCAT Center for Interface Science and Catalysis SLAC National Accelerator LaboratoryMenlo ParkCA 94025USA

The well-known anti-corrosive property of stainless steels is largely attributed to the addition of Cr,which can assist in forming an inert film on the corroding *** maximize the corrosion-resistant ability of Cr,a thorough study dealing with the passivation behaviors of this metal,including the structure and composition of the passive film as well as related reaction mechanisms,is ***,continuous electrochemical adsorptions of OH-groups of water molecules onto Cr terraces in acid solutions are investigated using DFT *** models with various surface conditions are *** is found to begin in the active region,and a fully coated surface mainly with oxide is likely to be the starting point of the passive *** calculated limiting potentials are in reasonable agreement with passivation potentials observed via experiment.

关键词： chromium acid solutions passive films interfaces modeling studies

Relationship between Hydrogen Diffusion and Blistering Nucleation and Growth

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Journal of Iron and Steel Research International 2016年第11期23卷 1188-1194页

作者： Jin-xu li Hang YIN Xi-na YANG Qian li Ping ZHANG Chun-qian XIE Yan-jing SU li-jie qiao Corrosion and Protection Center Environment Sensitive Fracture Laboratory(MOE)University of Science and Technology Beijing

The formation condition of hydrogen blister in 18Ni maraging steel without any inner or external stress was investigated. The results show that the critical diffusible hydrogen concentration of a blister forming is about 1.4×10^-5 , which is corresponding to the current density of 30 mA/cm^2 during cathodic charging in a sodium hydroxide solution. For a 0.1 cm thick sample, no matter the current density is equal to or much larger than the critical value, it spends at least about 132 h to form a hydrogen blister when hydrogen charging in single direction. It is approxi- mately equal to the time for hydrogen atom to diffuse throughout the sample, which exactly depends on the hydrogen diffusion coefficient and the penetration depth. The very first clear suggestion was reported that the incubation period for hydrogen blister nucleation was necessary. According to the Fick＇s laws, calculations show that the normalized hydrogen concentration in the escaping surface almost reaches 0.96 times of the charging surface, which means that the diffusion almost reaches a dynamic balance. A model was illustrated to describe the competitive relationship between hydrogen diffusion and blister formation.

关键词： hydrogen blister trap maraging steel hydrogen diffusion incubation time

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Rare Metals 2017年第7期36卷 591-595页

作者： Zhi-Jun Zuo De-An Pan li-Jun Wang Jian-Jun Tian Shen-Gen Zhang li-jie qiao Alex A.Volinsky School of Materials Science and Engineering University of Science and Technology Beijing Department of Mechanical Engineering University of South Florida

The effect of height on performance of the PZT/Ni cylindrical bilayered magnetoelectric （ME） com- posites was studied in situ in this paper. Multiple resonant peaks appear between 1 and 300 kHz frequency for cyl- inders of different heights. The first resonance frequency does not change with the cylinder height decreasing, but the second and the third resonant frequencies increase. The first three resonant modes radial, first-order height are attributed to the cylinder resonance, and second-order height resonance, respectively. The appropriate size and resonance frequency were chosen to obtain the highest ME voltage coefficient when designing cylindrical bilayered magnetoelectric devices. This article provides reference to design cylindrical magnetoelectric devices.

关键词： Cylindrical layered composites Height Resonant mode Demagnetization factor

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***数字用户线路阻抗不匹配信道模型研究

电子学报 2020年第2期48卷 403-406页

作者：李俏杰广东外语外贸大学数学与统计学院广东广州510006

基于数字信号传播理论中的反射原理,采用反射系数刻画线路阻抗不匹配程度,利用线路阻抗匹配时测量得到的信道数据(直接信道、远端串扰信道和近端串扰信道),建立了一个***数字用户线路阻抗不匹配时信道数学模型.当线路终端处于断开时,利... 详细信息

基于数字信号传播理论中的反射原理,采用反射系数刻画线路阻抗不匹配程度,利用线路阻抗匹配时测量得到的信道数据(直接信道、远端串扰信道和近端串扰信道),建立了一个***数字用户线路阻抗不匹配时信道数学模型.当线路终端处于断开时,利用该模型生成的信道数据与实际测量的信道数据基本吻合,证明了该模型的正确性.由于采用反射系数刻画线路阻抗不匹配程度,该信道模型可仿真终端设备在不同阻抗值的情况下对通信系统信噪比的影响,从而提出线路终端设备阻抗最大允许的变化范围,为终端设备制造商在阻抗设计时提供一定的理论指导.

关键词： G.fast 信道模型数字信号反射信噪比超宽带网络智慧家庭

Clinical Features of an Unrecognized 21-hydroxylase Deficiency Woman During Controlled Ovarian Hyperstimulation

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Chinese Medical Journal 2015年第17期128卷 2412-2413页

作者： Rui Yang Hong-Zhen li jie qiao Department of Obstetrics and Gynecology Reproductive Medical Center Peking University Third Hospital Beijing 100191 China

To the Editor： Nonclassic congenital adrenal hyperplasia （NCAH） due to 21-hydroxylase deficiency （21-OHD） is one of the most common autosomal recessive disorders. Affected individuals typically present signs and symptoms related to excessive androgens. In the process of assisted reproductive technique （ART）, the clinical features of NCAH may evade our attention and, therefore, he left untreated. Here, we present a case of NCAH, who underwent controlled ovarian hyperstimulation （COH）.

关键词：类固醇21-羟化酶肾上腺增生先天性世界卫生组织体征和症状雄激素类胰岛素注意力