首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
Rareearthelements (REEs)werewidelyappliedtotracingthesourcesofmaterialsandtostudyingtheirevolutionprocessesinmanyfieldsofearthscienceinconsiderationoftheirsimilarityandsystematicdiffer enceinchemicalproperties .Furthermore ,lanthanidesarebothimportantprod…  相似文献   

2.
许胜先  王志强 《稀土》2003,24(4):68-70
合成了十二种稀土锗钨钼酸根多元杂多配合物。利用元素化学分析和ICP相结合方法、IR等手段对配合物进行了初步表征。  相似文献   

3.
2 mercaptobenzothiazolewasfirstreportedbyHofmann[1 ] in 1 887.Ithasbeenusedasanacceleratorinthevulcanizationofrubberformanyyears .Todayitisstillbeingusedasamainacidicacceleratorinrubberindustry .Butithasdisadvantagesofvulcanizationreversionandeasyscorch[2 ] whe…  相似文献   

4.
Preparation and Characteristics of Rare Earth Loaded Titanium Dioxide   总被引:1,自引:0,他引:1  
Composite oxide catalysts Eu/TiO2, Ce/TiO2, Y/TiO2 (RE/TiO2) were prepared by impregnation method and characterized by means of UV-Vis spectroscopy, TEM and BET. The results indicate that the size of TiO2 has different elfeet on the modification efficiency. The catalytic activity of micron scale TiO2 increases by 136% and 59% owing to the addition of Y and Ce, respectively, while the catalytic activity of nanoscale TiO2 decreases due to the doping of Y and Ce.  相似文献   

5.
In order to combine the merits of rare earth organic complexes with excellent material performances of polymers,a polymerizable chelating agent, 3-allyl-2, 4-pentane dione (APD), was synthesized by phase transfer catalysis and its rare earth complexes were prepared. The compounds were characterized by EA, IR and ^1H NMR. Their UV spectra and fluorescence spectra were investigated. The effects of allyl on the luminescence properties of the complexes were studied.The results show that the sensitization of APD is changed by allyl in comparison with that of acetyl acetone (acac), and it becomes an ideal novel ligand of Eu. In addition, intramolecular energy transfer mechanism in the luminescence process in the complexes was also discussed in detail.  相似文献   

6.
ompoundsofpyrazolinehavepropertiesofkillingbacteriaandpromotingplantgrowth[1] . 5 Phenylpyrazolinedithioformateformsstablecomplexeswithmanytransitionmetalelements[1] .However ,thecomplexesofrareearthmetalhavenotbeenreported .Asanextensionofourpreviousstudies[…  相似文献   

7.
Rare Earth Elements-Doped LiCoO2 Cathode Material for Lithium-Ion Batteries   总被引:1,自引:0,他引:1  
Thedevelopmentoflithium ionbatteriesreliesonthesuccessfuldevelopmentoflithiumintercalationandde intercalationcompounds ,whichareusedasthecathodeandanodeactivematerials .Forthecathode ,LiCoO2 ,LiNiO2 andLiMn2 O4 areselectedasthecan didate .Amongthematerials ,thelayeredtransitionmetaloxideofLiCoO2 isregardedasthemostattrac tivecathodematerialforcommerciallithium ionbat terybecauseofitshighspecificcapacity ,highoperat ingcellvoltageandexcellentrechargeability .Recent ly ,moreextensivestudies…  相似文献   

8.
XPS Studies on Rare Earth Oxide LSCO/YSZ Electrodes   总被引:6,自引:0,他引:6  
The X-ray diffraction spectra and X-my photoelectron spectroscopy were measured for Sr-doped Lal-xSrx CoO3 materials with perovskite structure prepared by the solid-state reaction method. The influence of heat-treatment tempera-ture on the average crystal size of Lal-xSrx CoO3 was studied. The surface chemical states of Lal-xSrxCoO3 cathodes with different Sr-doped content were discussed. The experimental results show that average crystal size of Lal-xSrxCoO3 under the condition of heat-treatment in the range of 900- 1200℃ is larger than that at other temperatures, which is of benefit to forming porous electrodes. When La is replaced by Sr gradually, the oxygen vacancy concentration increases. It is of benefit to enhancing the transport property of oxygen ion.  相似文献   

9.
The effect of Y-base rare earth alloy in ultra-high hardfacing was observed by means of OM, SEM and XRD. Precipitated carbide can be metamorphosed and spheroidized in surfacing by adding Y-base rare earth alloy, which contributes to the increase of precipitated carbide. Rare earth combined with oxygen and sulfur can improve the morphology of slag inclusion as well as purify surfacing. The result shows proper rare earth alloy in surfacing can fine its microstmcture, improve hardness and impact toughness.  相似文献   

10.
The transparent PVC films were prepared by tape casting. In the process of preparation, rare earth nitrate, as a kind of modifier, was added to the solution of PVC and THF. These PVC films were tested after being crosslinked by ultraviolet light. It is found that the mechanical and physical properties of all the PVC films modified by rare earth nitrate are greatly enhanced.  相似文献   

11.
The influence of rare earths on the behavior of precipitation of 14MnNb,X60 and 10Mn V steels was studied by STEM, XRD, ICP and thermal simulation method. The main carbonitride precipitates are Nb(C, N), (Nb, Ti) (C, N) and V(C, N). In austenite RE delays the beginning of precipitation, and decreases the rate of precipitation. In ferrite RE promotes precipitation and increases the amount of equilibrium carbonitride precipitation. RE can make precipitates fine,globular and dispersed in the microalloyed steels. With the increase of the amount of RE in steel, the amount of precipitation increases. The promotion effect is weakened with excessive RE. RE has only little influence on the strength of microalloyed steel, but it can improve impact toughness effectively.  相似文献   

12.
水杨酸类稀土配合物的研究进展   总被引:2,自引:0,他引:2  
张秀英  张有娟  雷雪峰 《稀土》2004,25(6):63-67
综述了水杨酸类稀土配合物的类型、合成方法、结构特征和应用。  相似文献   

13.
StudyonRareEarthFerroceneMonocarboxylateComplexesLiMei(李梅)(BaotouRareEathResearchInstitute,Baotou014010,China)SunYuanhong(孙元洪...  相似文献   

14.
Themetalcomplexesofhydrazideshaveattractedconsiderableinterestowingtotheirantifungalandantibacterialactivities[1 ,2 ] .Theycanalsobeusedasanalyticalreagents[3 ]andextractingagentsformetalsalts[4 ] .Manycomplexesofhydrazideshavebeensynthesizedandcharacterized[5]…  相似文献   

15.
采用共沉淀法于低温下合成了含稀土氧化物La2O3,CeO2的紫红色陶瓷颜料,并将合成的颜料应用于陶瓷高温釉料中;此外,通过颜色测定SEM,XRD及能谱分析等手段对颜料的颜色、粒度及结晶构造等进行了表征,并探讨了颜料的呈色机制。结果表明:该颜料在釉料中呈色稳定,可以应用于1320℃的高温,随稀土氧化物含量增加,颜料中析出(La,Ce)(Mn,Fe,Cr)O3晶相,颜料由棕红色转变为紫红色。  相似文献   

16.
The doping effects of rare earth oxides Ho2O3 and Er2O3 on dielectric properties of BaTiO3-based ceramics were studied. After adding rare earth elements, grain growth in this system was inhibited and the grain size was reduced evidently which realized the fine-grained effect. In this system, the trivalent oxides Ho2O3 and Er2O3 were added to BaTiO3 ceramics. The rare earth oxides do not enter into inner lattice totally to replace A or B sites.Some of additives can improve dielectric strength by forming nonferroelectric phases, and the rest maintained at grain boundaries controls overgrowth of grains. The dielectric constant at room temperature is increased up to 3000 and the curve of TCC becomes flat.Meanwhile, the dielectric strength Eb becomes higher.  相似文献   

17.
Recently ,manystudiesonfine grainedBaTiO3 basedceramicsdopedwithrareearthelementshavebeenperformedbecauseitisharmlesstotheenviron mentbothinproductionandinapplication .Thiskindofmaterialiscommonlyusedasmultilayerceramicca pacitors (MLCC)ofEIAX7Rspecification .Theeffectsofrareearthoxidesonthedielectricpropertiesandreliabilityhavebeendiscussedinsever alrecentpapers ,whichconcludedthatrareearthox idesplayanimportantroleintheX7Rdielectricsandareveryeffectivetoenhancethereliabilitiesofdielec t…  相似文献   

18.
本文研究了RE(RE=DY、Eu、Sm、Tb)—HFA—TOPO—Triton X-100体系的激光诱导荧光光谱。拟定了时间分辨荧光光谱技术同时测定这四个稀土元素的分析方法,用于混合样品分析,获得了满意的结果。  相似文献   

19.
The cathode material plays an important role inthe performance of lithium ion batteries. Commerciallithium cells use lithium cobalt oxide cathodes and thehigh cost of this material has prompted the design andsynthesis of alternate insertion hosts. Among these al ternatives, spinel LiMn2O4 has been found to bepromising in terms of specific energy, non toxicity,and low cost[1~3]. It is thought that lithium man ganese oxides will be used in lithium ion batteries forel…  相似文献   

20.
水杨醛缩邻氨基苯酚稀土金属配合物的合成与表征   总被引:5,自引:0,他引:5  
报道了水杨醛缩邻氨基酚与La3+,Ce4+,Pr3+,Nd3+,Sm3+,Eu3+,Gd3+,Tb3+,Dy3+,Ho3+,Er3+,Tm3+,Yb3+,Lu3+等镧系稀土离子配合物的合成,通过红外光谱、紫外光谱、荧光光谱、摩尔电导、差热以及元素分析等对稀土配合物进行了表征,其组成分别为I:HML2·2H2O(M=La,Ce,Sm,Eu,Gd);II:ML·Y·X:(IIa:Y=H2O,M=Pr,Nd,Lu,X=Cl;M=Tb,X=NO3-。IIb:M=Dy,Ho,Er,Tm,Yb,Y=C2H5OH,X=Cl-),并推测了其可能的结构。还发现La3+和Lu3+对该配体有较强的激活作用,显著地增大了该配合物的荧光强度。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号