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Improving the hard magnetic properties by intragrain pinning for Ta doped nanocrystalline Ce-Fe-B alloys

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Journal of Materials Science & Technology 2019年第9期35卷 1877-1885页

作者： J.S.zhang w. Li X.F. Liao H.Y. Yu L.z. zhao H.X. zeng D.R. Peng z.w. Liu School of Materials Science and Engineering South China University of TechnologyGuangzhou510640China Innovative Center for Advanced Materials (ICAM) Hangzhou Dianzi UniversityHangzhou310012China

To develop Ce based permanent magnets with high performance/cost ratio, Ta doping is was employed to enhance the magnetic performance of Ce-Fe-B alloys. For melt spun Cei7Fe78-xTaxB6 (x = 0-1) alloys, the coercivity Hc increases from 439 to 553 kA/m with increasing x value from 0 to 0.75. Microstructure characterizations indicate that Ta doping is helpful for grain refinement. A second phase of TaB2 is observed in Ce17Fe77.25Tao.75B6 alloy, which acts as the pinning center of the magnetic domains, resulting in the change of coercivity mechanism from nucleation type to nucleation +pinning type. The micromagnetic simulation confirms that non-magnetic particles within hard magnetic phase can increase the demagnetization field around them and it is crucial for preventing the further magnetization reverse by pinning effect. Take the advantage of Ta doping for enhancing the coercivity, Ce content of Ce-Fe-B alloy can be further cut down to increase the remanence Jr due to the reduced volume fraction of CeFe2 phase and increased Fe/Ce ratio. As a result, a good combination of magnetic properties with Hc = 514 kA/m, Jr = 0.49 T, and the maximum energy product (BH)max = 36 kJ/m^3 have been obtained in Ce15Fe79.25Tao.75B6 alloy. It is expected that the present work can serve as a useful reference for designing new permanent magnetic materials with low-cost.

关键词： Melt-spinning Permanent magnets Second phase Coercivity mechanism Thermal stability

Influence of a liquid-filled compartment structure on the incoming shaped charge jet stability

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Defence Technology（防务技术） 2021年第2期17卷 571-582页

作者： X.D.zu z.X.Huang z.w.Guan X.C.Yin Y.M.zheng School of Mechanical Engineering Nanjing University of Science and TechnologyXiaolingwei 200Nanjing 210094China School of Engineering University of LiverpoolLiverpoolL693GQUK Department of Mechanics and Engineering Science Nanjing University of Science and TechnologyNanjing 210094China

Liquid-filled compartment structure consists of a bulk steel plate with matrix blind holes which are filled with liquid and a steel front plate to seal up the liquid with rings and *** liquid-filled compartment structure can resist the shaped charge warhead *** paper presents experimental and theoretical investigations of the penetration ability of the residual shaped charge jet emerging from the liquid-filled compartment structure after the penetration process at different impact *** the basis of shock wave propagation theory,the influence of the liquid-filled compartment structure on jet stability is *** interferences of the liquid backflow caused by a reflected shock wave and a back plate on jet stability under different impact angles are also *** addition,the range of the disturbed velocity segments of the jet at different impact angles and the penetration ability of the residual jet are obtained.A theoretical model is validated against the experimental penetration depths.

关键词： Compartment structure Shaped charge jet Shock wave Disturbance Stability

FACILE HYDROTHERMAL SYNTHESIS AND GROwTH KINETICS OF Fe-BASED MAGNETIC NANOPARTICLES

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Acta Metallurgica Sinica(English Letters) 2007年第6期20卷 434-440页

作者： C.X. You J.C. zhang Y. Shen z.w. Song Shool of Material Science and Engineering Shanghai University.Shanghai 200072 China

The facile hydrothennal method was used to synthesize Fe3O4 nanoparticles with an average diameter of 1 1nm. The pure body-centered cubic （bcc）-Fe nanoparticles were prepared by reduction of Fe3O4 nanoparticles powder in H2 atmosphere. The structure, morphology and magnetic＇properties of the products were characterized by X-ray powder diffraction （XRD）, transmission electron microscopy （TEM）, thermogravimetric analysis-differential scanning calorimetry （TGA-DSC） and vibrating sample magnetometer （VSM）. The results showed that the as-prepared Fe3O4 nanoparticles had a relatively homogeneous size. The particle diameters became bigger with the increase of reaction time. The growth kinetics of the Fe3O4 nanoparticles was also briefly discussed. The products exhibited superparamagnetic properties at room temperature and the specific saturation magnetization was dependent on the particle sizes.

关键词： Fe-based nanoparticle hvdrothermal specific saturation magnetization kinetics

Distribution of Be in a Ti-Based Bulk Metallic Glass Composite Containing B-Ti

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Journal of Materials Science & Technology 2017年第7期33卷 708-711页

作者： L.zhang w.Q.Li z.w.zhu H.M.Fu H.Li z.K.Li H.w.zhang A.M.wang H.F.zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences 110016 Shenyang China

In order to obtain a glassy matrix during quenching, Be is often selected as a constituent of the compositions of Ti/zr-based bulk metallic glass composites（BMGCs）. The in situ formed β phase in Be-bearing BMGCs was reported to be Be-free. However, a thorough investigation of the distribution of Be in BMGCs is still missing to date. In this work, the distribution of Be in a Ti_（47.5）zr_（33）Cu_（5.8）Co_3Be_（12.5）（at.%） BMGC was studied by the secondary ion mass spectrometry（SIMS） and the electron energy loss spectroscopy（EELS）.It is found that Be almost totally dissolves in the glassy matrix, but a very weak intensity of Be in β phase is still detectable by SIMS, and the content of Be in β-Ti is estimated to be about 0.3 at.%. Based on the recently established two-phase quasi-equilibrium of BMGCs, the distinct solubility of Be in the glassy matrix and in β-Ti has been explained.

关键词： Bulk metallic glass(BMG) Metallic glass composite Beryllium Quasi-equilibrium

Fe-Cr-Y_2O_3 MICRO-CRYSTALLINE COATINGS DEPOSITED BY SERIES ELECTRO-PULSE DISCHARGE

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Acta Metallurgica Sinica(English Letters) 2002年第4期15卷 331-338页

作者： Q. Xu,Y.D. He,D.R. wang,H.B. Qi,z.w. Li and w.Gao Beijing Key Laboratory for Corrosion, Erosion and Surface Technology, University of Science and Technology Beijing, Beijing 100083, China Department of Chemical and Material Engineering, The University of Lab. for Corrosion Univ. of Sci. and Technol. Beijing Beijing 100083 China

A new technique-series electro-pulse discharge (SEPD)-was developed as a sur-face coating process. In this technique, both positive and negative poles of a pulse power were used as the depositing electrodes with the substrate alloy as an induction electrode. Fe-Cr and Fe-Cr-Y2O3 micro-crystalline coatings were deposited on stain-less steel (Fe-18Cr-8Ni) surfaces. Oxidation at 950℃ in ambient air showed that the coatings greatly improved the oxidation resistance of the steel. The addition of dis-persed Y2O3 nano-particles into the alloy coatings was found to further reduce the scaling rate and enhance the adhesion of oxide scales.

关键词： series electro-pulse discharge Fe-Cr-Y2O3 micro-crystalline al-loy coating high-temperature oxidation

Cloning and Sequence Analysis of Lipoxygenase Gene cDNA from Cucumber Fruit (Cucumis sativus L.)

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分子植物育种 2007年第2期5卷 188-189页

作者： z.K. wang 　z.w. Qin　 X.Y. zhou　 D.Y. Song Horticulture College of Northeast Agricultural University Harbin 150030 China

Lipoxygenases are nonheme-iron-containing dioxygenases that catalyze the hydroperoxidation of unsatrated fatty acids containing a cis, cis-1,4-pentadiene structure producing hydroperoxy acids with conjugated dienes.

关键词：脂加氧酶基因克隆黄瓜种植

Noise Like Ultra-Short Bound Solitons Train

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光学学报 2003年第S1期23卷 401-402页

作者： Y.D. Gong P. Shum D.Y. Tang T.H. Cheng C. Lu X.Q. zhou z.w. Qi Y.L. Guan w.S.Man H. Y. Tam Institute for Infocomm Research Innovation Center Block 2 18 Nanyang Drive Singapore 637723. Network Technology Research Center School of Electrical & Electronic Engineering Nangyang TechnologicalUniversity Singapore 639798 Department of Electrical Engineering The Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong

Asymmetrical bound solitons train with pulsewidth of 103fs and separation of 585.5fs without any Cw components are observed from Figure-8 passive mode locked fiber laser, the separation and pulsewidth keep unchanged e... 详细信息

关键词： Optical fiber lasers Optical fiber solitons Optical pulse generation

Simulation System for Quality Prediction and Parameters Optimization in Machining Hydroxyapatite-SiCw Bioceramics

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Simulation System for Quality Prediction and Parameters Opti...

FURTHER STUDIES ON THE BENzOL-ADRENALINE CARDIO-VENTRICULAR FIBRILLATION

The 9th International Symposium on Advances in Abrasive Technology

作者： z.w. Niu, L. Li and X.M. Huang School of Mechanical Engineering, Shandong University of technology, zibo 255049, China

A simulation system was developed to forecast machining quality and optimize grinding parameters for the machining of hydroxyapatite-SiCw bioceramics. The system can forecast the surface quality of machined hydroxyapatite-SiCw bioceramics with high precision, optimize machining parameters and analyze the dominant factors. Based on the process database , the simulation system is applicable to various machining methods. It can help to raise the automaticity for the machining of hydroxyapatite-SiCw bioceramics and develop the farther intelligent system.

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Science in China,Ser.A 1962年第10期 1369-1376页

作者：沈霁春李士婉

has been shown that intravenous inieetion of adrenaline in dogs andcars under chloroform anaesrhesia induces a sudden arrest of the heart dueto ventrieular fibrillation[,]and it has also been known that benzol acts in... 详细信息

关键词： FURTHER STUDIES ON THE BENzOL-ADRENALINE CARDIO-VENTRICULAR FIBRILLATION