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Modification of Nonmetallic Inclusions in Steel with yttrium

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工程科学学报 1989年第6期 539-543页

作者： ТарасюкЛ.И. 蔡开科刘新华曲英

The modification affects of yttrium on formation of nonmetallicinclusions in steel has been studied by use of metallographic method. The effect of added quantity of modificater on type and size of inclusions was also ... 详细信息

关键词： yttrium modification nonmetallic inclusions

Synthesis, Characterization, Activity of yttrium（Ⅲ） Antibacterial and Antifungal Complexes Including 1,10-P henanth roli ne

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Chinese Journal of Chemistry 2012年第7期30卷 1531-1538页

作者：蔡梦军陈建定 Taha,Mohamed National Engineering Research Centre of Ultrafine Powder School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China Laboratoire de Rheologie des Matieres Plastiques FRE CNRS 2396Universite Jean Monnet23 Rue du Docteur Paul Michelon42023 St.-Etienne Cedex 2France

Two rare metal coordination complexes of yttrium（Ⅲ） including 1,10-phenanthroline, Y（phen）2（NO3）3 and （phenH）2[Y2（pydc）3（NO3）2.6H2O] （phen= 1,10-phenanthroline, pydc=2,6-pyridinedicarboxylate）, and a proton transfer compound （phenH＋）2（pydc2-） were synthesized and characterized by elemental analysis, molar conductance, infrared spectra （IR）, nuclear magnetic resonance （NMR） and thermal analysis. The proposed structures of yttrium complexes were exhibited. The in vitro biological activities of the newly synthesized complexes have also been investigated against Bacillus coli, Staphylococcus aureus and Candida albicans. The results showed that yttrium（Ⅲ） complexes including 1,10-phenanthroline exhibited better antibacterial/antifungal activity than their ligands and corresponding compounds.

关键词： yttrium 1,10-phenanthroline coordination complex antibacterial activity antifungal activity

Mechanism of Improving the Wearability of WC78-TiC14-Co8 Cemented Carbide with yttrium Addition

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Journal of Rare Earths 1997年第4期15卷 36-41页

作者：袁逸汪新义邬荫芳

The influence of yttrium addition on microstructure and wearability of WC78 TiC14 Co8 cemented carbide has been studied It is shown that the wearability of the carbide tool is significantly improved by adding trace amount of yttrium and the optimal adding amount is about 0 27%(wt)(in binder) Experimental results indicate that owing to adding yttrium, in as sintered cemented carbides the sizes of carbide grains and Co rich binder regions are reduced and their size homogeneity is improved, while in the binder, both dissolved contents of tungsten and titanium and volume proportion of the ductile α Co phase with f c c lattice are increased Therefore, the strength toughness of the binder and the cemented carbide which consists of the carbides and the binder are apparently enhanced Besides, it is found that many Y 2WO 6 particles appear along the WC/WC or WC/Co rich phase interfaces in as sintered carbide alloy with yttrium addition until 4 5%(wt), showing that during liquid phase sintering process of the alloys the segregation of yttrium atoms and Y 2WO 6 forming reaction might take place on the carbide particles/liquid binder interfaces, reducing the oxide films on the surface of WC particles and strengthening the cohesion of WC particles with Co rich binder

关键词： Rare earths yttrium Cemented carbide Wearability

Effect of Low Concentration of yttrium on Physiological Characteristics of Cucumber (Cucumis Sativus L.)

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Journal of Rare Earths 2007年第S2期25卷 236-241页

作者：王烁陈丹秦兆江董振宇鞠明超解冰凝 Department of Chemical and Biological Science Tianjin Normal University

There is no doubt that rare earth elements stand an important position among the essential elements of plant growth and it is long time since they are first used as plant growth promoters. Given their effects on microstructure, most reports are focused on the toxicology rather than promotion. Using cucumis sativus L. (Jin Chun No.5) as experiment material, we try to find out the nutritional effects of low Y3+ concentrations on cucumber seedlings′ leaves. The present paper suggests that the rare earth elements act as micronutrients at low concentrations while they give rise to toxicity at high concentration. Benefits defeat toxicity with concentration ranging from 5 to 25 μmol·L-1. Through careful study, at the Y(NO3)3 concentration of 10 μmol·L-1 the content of chlorophyll as well as the activities of SOD, Cu-Zn SOD and the POD are the highest. It indicates 10 μmol·L-1 is the optimum concentration of yttrium for promoting the cucumber growth.

关键词： rare earth elements yttrium physiological characteristics promoting effects cucumis sativus L.

Direct oxygen removal from titanium aluminide scraps by yttrium reduction

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Transactions of Nonferrous Metals Society of China 2022年第7期32卷 2428-2437页

作者： Li-na JIAO Qi-sheng FENG Shi-yu HE Bao-hua DUAN Zhi-he DOU Chong-he LI Xiong-gang LU State Key Laboratory of Advanced Special Steel&Shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering Shanghai UniversityShanghai 200072China School of Metallurgy and Materials Engineering Jiangsu University of Science and TechnologyZhangjiagang 215600China Key Laboratory for Ecological Metallurgy of Multimetallic Mineral Ministry of EducationNortheastern UniversityShenyang 110819China Shanghai Special Casting Engineering Technology Research Center Shanghai 201605China School of Materials Science and Engineering Shanghai Dianji UniversityShanghai 201306China

Titanium aluminum(TiAl)scraps with a high oxygen content were treated with yttrium(Y)in a liquid chemical deoxidization process for *** Gibbs free energy and the equilibrium constant of the deoxidization reaction were calculated,and the effects of the yttrium content and the system pressure on the oxygen content in the product were *** results showed that the oxygen in TiAl scraps could be removed by yttrium,and the oxygen content of the deoxidized TiAl scraps had only 10%of the original content after ***,the oxygen content of the deoxidized TiAl scraps was decreased with the increase of yttrium *** higher the chamber pressure,the greater the oxygen content in the final TiAl *** results were consistent with calculated *** microstructure of the deoxidized alloys was akin to that of the original material;however,Y_(2)O_(3) particles were observed in the deoxidized alloys.

关键词： titanium aluminum scrap yttrium deoxidation recycling

Effects of yttrium addition and aging on mechanical properties of AA2024 fabricated through multi-step stir casting

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Transactions of Nonferrous Metals Society of China 2020年第2期30卷 288-302页

作者： CH.S.VIDYASAGAR D.B.KARUNAKAR Metallurgical and Materials Engineering Department Indian Institute of Technology Roorkee-247667India Mechanical and Industrial Engineering Department Indian Institute of Technology Roorkee-247667India

The effects of yttrium and artificial aging on AA2024 alloy were *** developed samples were further subjected to artificial aging at 190℃for 1-10 h with an interval of 1 *** metallurgical characterization was done by scanning electron microscope and X-ray *** mechanical characterization like hardness and tensile strength of the samples was done using computerized Vickers hardness testing machine and universal testing *** microstructures revealed that addition of yttrium refined theα(Al)matrix and led to the formation of Al-Cu-Y intermetallic in the shape of Chinese script which strengthened the *** to the base metal,samples with yttrium addition showed better mechanical *** sample reinforced with 0.3 wt.%yttrium showed the highest mechanical properties with the hardness of 66 HV,UTS of 223 MPa,YS of 180 MPa,and elongation of 20.9%.The artificially aged samples showed that the peak hardening of all the samples took place within 5 h of aging at 190℃with Al2 Cu *** changed the intermetallic from Chinese script to the fibrous *** optimum amount of yttrium addition to AA2024 was found to be 0.3 wt.%.

关键词： yttrium artificial aging mechanical properties multi-step stir casting precipitation microstructure characterization

Fabrication of SiC fibres from yttrium-containing polycarbosilane

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Transactions of Nonferrous Metals Society of China 2012年第4期22卷 879-886页

作者：杨大祥宋永才余煜玺赵晓峰肖平装甲兵工程学院再制造技术重点实验室北京100072 国防科技大学陶瓷纤维及其复合材料重点实验室长沙410073 厦门大学材料学院材料科学与工程系福建省防火阻燃材料重点实验室厦门361005 曼彻施特大学材料科学中心

The yttrium as a sintering aid was introduced into polycarbosilane（PCS） to prepare yttrium-containing PCS（PYCS）.Two types of yttrium-containing SiC fibres,the SiC（OY） fibres and the SiC（Y） fibres,were fabricated with *** structural evolution and the associated properties on changing from SiC（OY） to SiC（Y） fibres during the sintering process were *** chemical composition of the SiC（OY） fibres is SiC1.53O0.22Y0.005 with an amorphous *** composition of SiC（Y） fibres is *** fibres are composed of a large number of β-SiC crystallites with a size of 50 nm and a small amount of α-SiC *** tensile strength and fracture toughness of the SiC（OY） fibres are 2.25 GPa and 2.37 MPa·m1/2,respectively,and 1.61 GPa,1.91 MPa·m1/2,respectively for SiC（Y） *** SiC（Y） fibres have a higher thermal stability than the SiC（OY） fibres.

关键词： polycarbosilane yttrium silicon carbide fibre

Determination of Compositions and Stability Constants of Holmium and yttrium Complexes with Tribromoarsenazo by Linear Regression Method

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Journal of Rare Earths 1991年第1期9卷 5-9页

作者：魏永巨丁儒乾 Department of Chemistry Hebei Teachers' College Shijiazhuang 050091China

According to the appearing of isosbestic point in the absorption spectra of Ho/Y-Tribromoarsenazo (TBA)systems,the complexation reaction is considered to be M+nL=ML_n.A method has been proposed based on it for calculating the mole fraction of free complexing agent in the solutions from spectral *** two linear regression formula have been introduced to determine the composition,the molar absorptivity,the conditional stability constant of the complex and the concentration of the complexing agent. This method has been used in Ho-TBA and Y-TBA ***^(3+)and Y^(3+)react with TBA and form 1: 2 complexes in HCl-NaAc buffer solution at pH *** molar absorptivities determined are 1.03×10~8 and 1.10×10~8 cm^2·mol^(-1),and the conditional stability constants(logβ_2)are 11.37 and 11.15 *** considering the pH effect in TBA complexing,their stability constants(log β_2^(ahs))are 43.23 and 43.01. *** new method is adaptable to such systems where the accurate concentration of the complexing agent can not be known conveniently.

关键词： Holmium yttrium Tribromoarsenazo Absorption spectra Stablilty constant Linear regression method

FLUORESENCE　ENHANCEMENT　OF　DYSPROSIUM－TIRON　SYSTEM　BY　yttrium　AND　ITS　APPLICATION

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Chinese Chemical Letters 1994年第3期5卷 239-242页

作者： Jinn Tian HU Zhi Kun SI Gui Ynn ZHU Wei JIAMG and Wen Quan AI(Department of Chemistry,Shandong Univeersity,Jinan,250100)

A fluorescence enhancement phenomenon was observed for the first time by adding yttrium ion to dysprosum-pyrocatechol-3,5-disulphonic acid (tiron )system at pH *** excitation and em ission wavelengths were 323 and 575nm,*** presence of Y(3+),the fluorescence intensity was increased about 15-fold and it was a linar fun ction of the concentration of dysprosium in the range of 8.0× 10(-8)-9. 0×10(-6)mol dm(-3). The detection limit,was 1. 0×10(-10)mol dm(-3).The system was used for the spectrofluotimetric determination of dysprosium,with satisfactory results. Tie mechanism of the enhanced fluoreseence was proposed.

关键词： ITS yttrium APPLICATION AND