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Influence of NaCl on dechromization of Cu-cr-Al alloy in H_3PO_4 solution

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中国有色金属学会会刊：英文版 2010年第1期20卷 123-127页

作者：刘玉文李雅莉张瑞军王海燕彭桂荣刘建华 State Key Laboratory of Metastable Materials Science and Technology Yanshan University Department of Basic Medical Tangshan Vocational Technology College Department of Environmental and Chemical Engineering Yanshan University

The dechromization of Cu-cr-Al alloys was investigated by a static immersing corrosion test. The influence of NaCl on the dechromization was analyzed by electrochemical test, scanning electron microscopy, optical microscopy and X-ray fluorescence spectroscopy. The results show that the dechromization of Cu-cr-Al alloys will take place in a H3PO4 solution of 11.32 mol/L at 55 ℃. And the corrosion process occurs initially at the interface between Cu and cr phase, and then extends inward cr-phase inside. The addition of NaCl into H3PO4 solutions can shorten the dechromization incubation time, decrease the dechromization temperature and concentration of H3PO4 solution, and increase the tendency of dechromization. But, the NaCl scarcely has an effect on the form and structure of chromium depleted-layer.

关键词： NaCl溶液磷酸溶液 Al合金扫描电子显微镜 X射线荧光光谱铜铬合金 Cu cr

Radiation Losses in the Microwave X Band in Al-cr Substituted Y-Type Hexaferrites

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Chinese Physics Letters 2017年第4期34卷 35-38页

作者： D.Basandrai R.K.Bedi A.Dhami J.Sharma S.B.Narang K.Pubby A.K.Srivastava Research Scholar Department of Physics I. K. Gujral Punjab Technical University Jalandhar India Department of Physics Lovely Professional University Phagwara India principal Satyam Institute of Engineering & Technology Amritsar India Department of Electronic Technology Guru Nanak Dev University Amritsar India

We present a study on radiation losses in the microwave X band in Al-cr substituted Y-type hexaferrites, namely Ba2Mg2Alx/2crx/2Fe12-xO22 （x = 0, 0.5 and 1.0）. The study is performed by means of a vector network analyzer, Fourier transform infrared spectroscopy, a vibrating sample magnetometer and x-ray powder diffraction. Ba2Mg2Fe12O22 hexaferrite shows radiation loss of -37.25dB （99.999% loss） at frequency 9.81 GHz, which can be attributed to its high value of saturation magnetization, i.e., 22.08emu/g. Moreover, we obtain that magnetic properties have strong influence on the radiation losses.

关键词： Ba Al Radiation Losses in the Microwave X Band in Al-cr Substituted Y-Type Hexaferrites cr

Effect of Sputtered TiAlcr Coatings on Oxidation and Hot Corrosion Resistance of Ti-24Al-14Nb-3V

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Journal of Materials Science & Technology 2001年第5期17卷 501-506页

作者： Fuhui WANG, Chunhong GUAN, Zhaolin TANG and Weitao WU State Key Laboratory for Corrosion and Protection, Institute of Metal Research, The Chinese Academy of Sciences, Shenyang 110016, China Lab. for Corrosion and Protection Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

The effect of sputtered Ti-50Al-10cr and Ti-50A1-20cr coatings on both isothermal and cyclic oxidation resistance at 800-900℃ and hot corrosion resistance at 850℃ of Ti-24Al-14Nb-3V was investigated. Results indicated that Ti-24Al-14Nb-3V alloys exhibited poor oxidation resistance due to the formation of Al2O3+TiO2+AlNbO4 mixed scales in air at 800-900℃ and poor hot corrosion resistance due to the spoliation of scales formed in Na2SO4+K2SO4 melts at 850℃. Both Ti-50Al-10cr and Ti-50Al-20cr coatings remarkably improved the oxidation and hot corrosion resistance of Ti-24Al-14Nb-3V alloy.

关键词： Ti cr Effect of Sputtered TiAlcr Coatings on Oxidation and Hot Corrosion Resistance of Ti-24Al-14Nb-3V Al

First-principles study on electronic structure, magnetic and dielectric properties of cr-doped Fe_3C

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Journal of Central South University 2016年第9期23卷 2173-2181页

作者：杨建平陈津李伟韩培德郭丽娜 College of Materials Science and Engineering Taiyuan University of Technology

The first-principles calculations were performed to investigate the electronic structure, magnetic and dielectric properties of cr-doped Fe_3C, in comparison to those of pure Fe_3C and cr_3C. The obtained results show that the thermodynamic stability of crdoped Fe_3C becomes weaker in terms of the larger formation enthalpy, on the contrary, the metallicity and covalency are found to strengthen to some extent. The magnetic moments of Fe_3C, Fe_(11)crC_4(g), and Fe_(11)crC_4(s) are respectively 21.36 μB/cell, 16.92 μB/cell, and 17.62 μB/cell, and in Fe_(11)crC4(g) and Fe_(11)crC_4(s), the Fe of Wyckoff positions of 8d and 4c is substituted by cr. The local magnetic moment of cr at 8d site is larger than that at 4c site in the doped structure, which is opposite to that of Fe. In low frequency band, the permittivity follows the ranking of Fe_(11)cr C_4(s)>cr_3C>Fe_(11)cr C_4(g)>Fe_3C. Once exceeding a certain frequency, the sequence will be broken. Besides the electron transition, the polarization of atoms also makes a contribution to the dielectric properties.

关键词：第一性原理计算 Fe3C cr掺杂电子结构介电性能介电常数磁性 cr

MIcrOSTRUCTURES AND MECHANICAL PROPERTIES OF RAPIDLY SOLIDIFIED Al-Fe-cr-Zr-V-Si ALLOY AND THEIR THERMAL STABILITY

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中国有色金属学会会刊：英文版 1998年第3期8卷 122-125页

作者： Xiao, Yude Li, Songrui Li, Wenxian Wang, Richu Central South Univ of Technology Changsha China

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１ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｍｅｃｈａｎｉｃａｌｐｒｏｐｅｒｔｉｅｓｏｆｔｈｅｃｏｎｖｅｎｔｉｏｎａｌａｅｒｏｎａｕｔｉｃａｌｈｉｇｈｓｔｒｅｎｇｔｈａｌｕｍｉｎｉｕｍａｌｌｏｙｓｄｅｇｅｎｅｒａｔｅｒａｐｉｄｌｙｗｈｅｎｔｈｅｔｅｍｐｅｒ...

关键词： rapid solidification powder metallurgy heat resistant aluminium alloy Al Fe cr Zr V Si

Growth and Characteristics of Tunable Laser crystals β-Ga2O3∶cr

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Journal of Rare Earths 2006年第Z1期24卷 156-158页

作者： Zhang Jungang Xia Changtai Deng Qun Xu Wusheng Shi Hongsheng Wu Feng Xu Jun Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China GE (China) Research and Development Center Co. Ltd. Shanghai 201203 China GE (China) Research and Development Center Co. Ltd. Shanghai 201203 China GE (China) Research and Development Center Co. Ltd. Shanghai 201203 China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China

β-Ga2O3∶cr single crystals have potential applications for tunable laser. In β-Ga2O3 crystal structure cr3+ ions are in octahedron other than tetrahedron. So the cr3+ ions are influenced by low field of β-Ga2O3 that results the 4T2 to 4A2 transition and show broad emission around 690 nm. β-Ga2O3 single crystals doped with different cr3+ concentrations were grown by floating zone technique. Their absorption spectra and fluorescence spectra were measured at room temperature. The values of field splitting parameter Dq and Racah parameter B were calculated based on the absorption spectra.

关键词： β-Ga2O3 cr floating zone technique tunable laser

cr Stable Isotope Fractionation in Arbuscular Mycorrhizal Dandelion and cr Uptake by Extraradical Mycelium

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Pedosphere 2015年第2期25卷 186-191页

作者： REN Bai-Hui WU Song-Lin CHEN Bao-Dong WU Zhao-Xiang ZHANG Xin State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of Sciences

As common soil fungi that form symbioses with most terrestrial plants,arbuscular mycorrhizal(AM) fungi play an important role in plant adaptation to chromium(cr) contamination.However,little information is available on the underlying mechanisms of AM symbiosis on plant cr resistance.In this study,dandelion(Taraxacum platypecidum Diels.) was grown with and without inoculation of the AM fungus Rhizophagus irregularis and cr uptake by extraradical mycelium(ERM) was investigated by a compartmented cultivation system using a cr stable isotope tracer.The results indicated that AM symbiosis increased plant dry weights and P concentrations but decreased shoot cr concentrations.Using the cr stable isotope tracer technology,the work provided possible evidences of cr uptake and transport by ERM,and confirmed the enhancement of root cr stabilization by AM symbiosis.This study also indicated an enrichment of lighter cr isotopes in shoots during cr translocation from roots to shoots in mycorrhizal plants.

关键词：同位素示踪技术同位素分馏根外菌丝丛枝菌根铬浓度蒲公英 cr 稳定

Wear and corrosion resistance of laser remelted and plasma sprayed Ni and cr coatings on copper

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中国有色金属学会会刊：英文版 2004年第5期14卷 885-889页

作者：梁工英黄俊达安耿 Department of Materials Physics Science School Xi'an Jiaotong University Xi'an 710049 China Department of Mechanical Engineering The Hong Kong Polytechnic University Hong Kong China

Nickel and chromium coatings were produced on the copper sheet using plasma spraying and laser remelting. The sliding wear test was achieved on a block-on-ring tester and the corrosion test was carried out in an acidic atmosphere. The corrosive behaviors of both coatings and original copper samples were investigated by using an impedance comparison method. The experimental results show that the nickel and chromium coatings display better wear resistance and corrosion resistance relative to the original pure copper sample. The wear resistance of the coatings is 812 times as large as original samples, and the wear resistance of laser remelted samples is better than that of plasma sprayed ones. The corrosion resistance of laser remelted nickel and chromium samples is better than that of plasma sprayed samples respectively. The corrosion rate of chromium coatings is less than that of nickel coatings, and the laser remelted cr coating exhibits the least corrosion rate.

关键词：等离子喷涂工艺激光技术铜涂层 cr Ni 耐腐蚀性

Passively Q-Switched Nd,cr:YAG Laser Simultaneous Dual-Wavelength Operation at 946 nm and 1.3μm

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Chinese Physics Letters 2016年第7期33卷 76-79页

作者：林斌张秋琳张东香冯宝华何京良张景园 Key Laboratory of Optical Physics Institute of PhysicsChinese Academy of Sciences State Key Lab of crystal Materials Shandong University Department of Physics Georgia Southern University

A diode-end-pumped Q-switched high-efficiency Nd, cr：YAG laser with simultaneous dual-wavelength emission at 946nm and 1.3μm is demonstrated. The maximum output power of 1.93 W with simultaneous dual-wavelength operation is achieved at an absorbed pump power of 13.32 W and an absorbed slope efficiency of 15.15%. The maximum optical-optical efficiency is 14.49% with pulse widths of 16.38ns at 946nm and 26.65ns at 1.3μm. A maximum total repetition rate of 43.25 kHz is obtained.

关键词： YAG as Passively Q-Switched Nd,cr:YAG Laser Simultaneous Dual-Wavelength Operation at 946 nm and 1.3 of nm Nd cr