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Journal of University of Science and Technology Beijing 2008年第6期15卷 753-757页

作者： Xiaoqian Bao Xuexu gao Maocai Zhang yi Qiao Xiaoyan Guo Jie zhu Shouzeng Zhou State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

The effects of Cu addition and annealing treatment on the magnetic properties and microstructure of Ndl2.3Fe81.7-xCuxB6 （x=0-1.2） ribbons melt-spun and annealed were systematically investigated by the methods of vibrating sample magnetometer （VSM）, X-ray diffraction （XRD）, and transmission electron microscopy （TEM）. Optimum magnetic properties were achieved by annealing melt-spun Nd12.3Fe81.5Cu0.2B6 ribbons at 550℃ for 15 min, which only contained Nd2Fe14B phase. The remanence, coercive force, and maximum energy product increase by 18.4%, 36.2%, and 49% respectively compared with those of Cu-free samples. The sig- nificant improvement in magnetic properties originates from the freer grains of the samples by introducing Cu, which leads to the stronger exchange-coupling between neighboring grains.

关键词： Nd-Fe-B magnets Cu addition annealing treatment microstructure magnetic properties

A review of flexible perovskite oxide ferroelectric films and their application

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Journal of Materiomics 2020年第1期6卷 1-16页

作者： Wenxiu gao yi zhu Yaojin Wang Guoliang Yuan Jun-Ming Liu School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing210094China Laboratory of Solid State Microstructure and Innovation Center of Advanced Microstructures Nanjing UniversityNanjing210093China

Many perovskite oxide ferroelectrics(***_(1-x)Ti_(x)O_(3),BaTiO_(3),LiNbO_(3))are born with multitudinous robust performances and have been widely used in sensors,actuators,surface acoustic wave devices,and memories et ***,their hardness,brittleness and harsh synthesis conditions(*** temperature and oxygen ambience)restrain their application into flexible electronic devices which are significant components among the three pillars of modern society development,***,information and *** we review the preparation of flexible devices based on these oxide ferroelectrics,including transferring these freestanding films to flexible substrates after separating ferroelectric oxide films from the hard substrates,such as Si and SrTiO_(3) crystals,and also direct fabrication methods without transferring ***,we summarize three kinds of representative flexible devices,*** ferroelectric memories,sensors and *** inorganic electronics not only show excellent electric properties competitive with those corresponding electronics on hard substrates but also exhibit good flexibility similar to many organic flexible electronics.

关键词： Perovskite oxides Flexible devices Sensors Energy harvesters Memories

Kerr frequency comb with varying FSR spacing based on Si3N4 micro-resonator

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Science China(Information Sciences) 2020年第11期63卷 269-275页

作者： Yuedi DING Yu gao Cheng ZENG Shanlin zhu Qingzhong HUANG yi WANG ying HUANG Jinsong XIA Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology

In this paper, we experimentally investigate a novel feedback loop scheme to generate optical frequency comb with varying free spectral range（FSR） spacing in a high-Q silicon nitride（Si3N4） micro-ring resonator. By selecting and amplifying different feedback sidebands, comb line spacing varying from 1-fold to 6-fold FSRs is successfully achieved. This approach could be beneficial to tune the comb repetition rate which is an important parameter for many applications, such as optical coherent communications, optical metrology and arbitrary waveform generation.

关键词： feedback loop free spectral range silicon nitride Kerr frequency combs micro-ring resonator

Agglomeration behavior of alumina inclusions and calcium aluminate inclusions on molten nickel-based superalloy surface

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Journal of Iron and Steel Research International 2023年第11期30卷 2318-2327页

作者： Rui-zhi gao Lin-zhu Wang Chao-yi Chen Shu-feng Yang Xiang Li yin Zhang School of Materials and Metallurgy Guizhou UniversityGuiyang550025GuizhouChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Department of Materials and Metallurgy Engineering Guizhou Institute of TechnologyGuiyang550003GuizhouChina

Understanding the interactive forces of inclusions on the surface of molten nickel-based superalloys and finding methods to disperse these inclusions help improve performance and service *** aggregation behavior of aluminum oxide(Al_(2)O_(3))and calcium aluminate inclusions with different sizes and spacings on the surface of molten nickel-based superalloys was observed in-situ using a high-temperature confocal laser scan *** attractive force acted on Al2O3 inclusions with radii of 3.5-6μm was found ranging from 6.2×10-18 to 3.6×10-15 N,and that of CaO·2Al2O3(CA2)inclusions with radii of 3-5.5μm ranging from 3.5×10-19 to 8.3×10-15 *** capillary force acted on inclusions on the surface of nickel-based superalloy was calculated based on the Kralchevsky-Paunov model and investigated as a function of inclusion size,spacing,and *** calculated results were in the same trend as the experimental *** capillary force acted on inclusions was also affected by their contact angle,the density,surface energy,and oxygen content of the molten *** decreased with increasing alloy density and decreasing contact angle between inclusion with ***,the attractive force acted on Al2O3 inclusions was smaller on the surface of molten nickel-based superalloy than that of molten *** the oxygen content in the molten nickel-based alloy could increase its surface energy,and the attractive force acted on the inclusions would *** the oxygen content in the molten nickel-based alloy decreased from 0.05 to 0.0001 wt.%,the capillary force acted on the Al2O3 inclusions decreased from 1.7×10-18 to 3.6×10-19 N,reduced by 79%(1.4×10-18 N).

关键词： Inclusion Nickel-based superalloy Capillary force Alumina Calcium aluminate

Novel Mn-Ce bi-oxides loaded on 3D monolithic nickel foam for low-temperature NH_(3)-SCR de-NO_(x):Preparation optimization and reaction mechanism

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Journal of Rare Earths 2022年第2期40卷 268-278,I0003页

作者： Shuquan Ni Xiaolong Tang Honghong yi Fengyu gao Chengzhi Wang yiran Shi Runcao Zhang Wenjuan zhu School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants Beijing 100083China

This study explored the superior citrate method(CM)to synthesize Mn-Ce bi-oxides on 3 D monolithic Ni-foam(NF)catalysts for the selective catalytic reduction of NO by NH_(3)(NH_(3)-SCR).The 17 wt%Mn(7)Ce(3)O_(x)/NF(CM-17)catalyst shows the NO_(x)conversion of 98.7%at 175℃and 90%in the presence of 10 vol%H2 *** is revealed that the combination of surface-active oxygen(formed by high-level oxygen vacancies)and strongly oxidized Mn4+species promots the Fast-SCR reactions,in which Mn4+species play a leading role in NH_(3)-SCR reaction,and the unsaturated Ni atoms and also Ce3+species promote electron exchange and thus improve the redox *** coexistence mechanisms of Fast-SCR reactions and E-R pathways are observed over Mn-CeO_(x)/NF catalyst,which may be promoted by the Br?nsted sites at low *** addition,the heat resistance,stability,3 D monolithic porous structure and excellent physical properties of foam nickel provide a unique growth substrates for catalysts preparation and reaction sites for NO_(x)***,industrial application of Mn-Ce bioxides loaded on 3 D monolithic is proposed to be achieved through reasonable preparation methods.

关键词： NH_(3)-SCR Low temperature Citrate method Fast-SCR 3D monolithic catalysts Oxygen vacancies

Prevalence of Epstein-Barr virus infection and characteristics of lymphocyte subsets in newly onset juvenile dermatomyositis

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World Journal of Pediatrics 2021年第2期17卷 205-209页

作者： Qi Zheng Kun zhu Cai-Na gao yi-Ping Xu Mei-Ping Lu Department of Rheumatology Immunology and AllergyChildren’s HospitalZhejiang University School of Medicine57#Zhu Gan RoadHangzhou 310000China Department of Pathology Children's HospitalZhejiang University School of MedicineHangzhouChina

Background The underlying etiology of juvenile dermatomyositis(JDM)is unknown.T cell deficiency as well as Epstein-Barr virus(EBV)infection had been suspected to be involved in the pathogenesis,but it has been poorly evaluated in JDM *** This study described the traits of T and B lymphocyte subsets in newly onset JDM patients and the incidence of EBV infection in JDM patients compared with match *** developed JDM patients from 2014 to 2018 were included in the *** with different markers(CD3+,CD3+CD4+,CD3+CD8+,CD3-CD19+and CD3-CD16+CD56+)were tested with flow cytometry in the first admission or after 6 months of *** analysis was conducted to compare the EBV infection in the group of JDM patients and *** We observed that JDM patients had higher positive rate of Epstein-Barr nuclear antigen-immunoglobulin G(IgG)(P<0.0001)as well as EBV capsid antigen-IgG(P<0.05)than normal ***3-CD16+CD56+lymphocyte was found to be extremely low in early stage of JDM patients,but increased after 6 months of treatment(P=0.0091).Conclusions The level of CD3-CD16+CD56+cells may associate with the clinical course of *** may act as an environmental factor predisposing patients to the development of JDM.

关键词： Epstein-barr virus Juvenile dermatomyositis Lymphocytes

Diversity and abundance of resistome in rhizosphere soil

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Science China(Life Sciences) 2020年第12期63卷 1946-1949页

作者： Jian Cao Fei Liu Baoli zhu yi Shi George Fu gao CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Savaid Medical School University of Chinese Academy of SciencesBeijing 100049China National Institute for Communicable Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijing 102206China

Dear Editor,Antibiotic resistance genes(ARGs) have posed a huge threat to public health, causing great economic cost worldwide(Nathan and Cars, 2014). Soil microbiota represents an important reservoir of diverse and ancient ARGs(Bahram et al.,2018). The horizontal gene transfer(HGT) including conjugation and transformation can lead to the exchange of resistance genes between soil microbes and clinical pathogens(Forsberg et al., 2012). However, the transfer of ARGs between genomes and habitats are rarely observed in *** composition significantly correlates with the underlying structure of bacterial communities both across and within soil types, suggesting bacterial phylogeny structures resistomes in soil across habitats(Forsberg et al., 2014).

关键词： soil rhizosphere habitat

A Triangular Decomposition Algorithm for Differential Polynomial Systems with Elementary Computation Complexity

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Journal of Systems Science & Complexity 2017年第2期30卷 464-483页

作者： zhu Wei gao Xiao-Shan Key Laboratory of Mathematics Mechanization Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China

In this paper, a new triangular decomposition algorithm is proposed for ordinary differential polynomial systems, which has triple exponential computational complexity. The key idea is to eliminate one algebraic variable from a set of polynomials in one step using the theory of multivariate resultant. This seems to be the first differential triangular decomposition algorithm with elementary computation complexity.

关键词： Differential polynomial system regular triangular set saturated triangular set triangular decomposition.

Random Weighting Estimation Method for Dynamic Navigation Positioning

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Chinese Journal of Aeronautics 2011年第3期24卷 318-323页

作者： gao Shesheng gao yi ZHONG Yongmin WEI Wenhui School of Automation Northwestern Polytechnical University Xi 'an 710072 China Department of Mechanical Engineering Curtin University WA6845 Australia

This paper presents a new random weighting estimation method for dynamic navigation positioning. This method adopts the concept of random weighting estimation to estimate the covariance matrices of system state noises and observation noises for controlling the disturbances of singular observations and the kinematic model errors. It satisfies the practical requirements of the residual vector and innovation vector to sufficiently utilize observation information, thus weakening the disturbing effect of the kinematic model error and observation model error on the state parameter estimation. Theories and algorithms of random weighting estimation are established for estimating the covariance matrices of observation residual vectors and innovation vec- tors. This random weighting estimation method provides an effective solution for improving the positioning accuracy in dynamic navigation. Experimental results show that compared with the Kalman filtering, the extended Kalman filtering and the adaptive windowing filtering, the proposed method can adaptively determine the covariance matrices of observation error and state error, effectively resist the disturbances caused by system error and observation error, and significantly improve the positioning accu- racy for dynamic navigation.

关键词： estimation navigation error random weighting estimation dynamic navigation positioning covariance matrix kinematic model error observation model error

Escape and Stand of the Pluto Atmosphere

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Communications in Theoretical Physics 2002年第7期38卷 125-127页

作者： gao Chong-yi School of Physical Science and Technology Lanzhou University Lanzhou 730000 China

Molar mass μmin of the lightest gas, which will exist "forever" in the atmosphere at the planet surface,can be evaluated by Jeans rule. The μmin of Pluto is 17.3 g@ mol-1. It is evident that both N2 and CO can be major atmospheric composition at the Pluto surface, and will exist "forever". CH4 can only be escaping slowly from Pluto atmosphere, and still holds quite a proportion in current Pluto atmosphere. However, it will not escape from Titan (or Jupiter, Saturn) atmosphere largely, and will exist "forever". Given the quantitylevelof partial pressure of CH4 in Pluto and Titan (or Jupiter, Saturn) original atmosphere is the same, it will be clear that the current partial pressure of CH4 in Pluto surface atmosphere is 10-3 Pa.

关键词： planet atmosphere, Pluto atmosphere, Jeans rule, atmospheric composition, escape