Effect of Rare Earth Elements on Quantity Growth of Crops

Ｒａｒｅｅａｒｔｈ (ＲＥ)ｍｉｃｒｏ ｆｅｒｔｉｌｉｚｅｒｓｈａｖｅｂｅｅｎｕｓｅｄｉｎａｇｒｉｃｕｌｔｕｒｅｐｒｏｄｕｃｔｉｏｎｉｎＣｈｉｎａｓｉｎｃｅ 1 970ｓ ,ａｎｄｔｈｅｓｅｍｉｃｒｏ ｆｅｒｔｉｌｉｚｅｒｓａｒｅｓａｌｔｓｏｆｍｉｘｅｄＲＥｓ ,ｗｈｉｃｈｍａｉｎｌｙｉｎｃｌｕｄｅＬａ ,Ｃｅ ,ＰｒａｎｄＮｄ[1,2 ] .ＰｒｅｖｉｏｕｓｓｔｕｄｉｅｓｓｈｏｗｔｈａｔｔｈｅＲＥｉｎｓｕｒｆａｃｅｓｏｉｌａｌｍｏｓｔｄｏｅｓｎｏｔｍｉｇｒａｔｄｏｗｎｗａｒｄａｔａｌｌａｎｄｔｈｕｓｂｅａｃｃｕｍｕｌａ…     

Effect of Rare Earth Elements on Quantity Growth of Ctrps

The effects of rare earth on the growth of rice,rape and soybean in three kinds of soils were studied with the method supposed by Economic Co-operation and Development organization(OECD),and the EC50(median growth concenrtation)values were obtained,The inhibition of RE on the growth of rice and rape in red soil and on the growth of soybeanin yellow fouvo-aquic soil is higher with stronger poison effects.Compared with other heavy metals such as Hg,Cd,Pb,As,the poison of RE on crops in weaker.     

Study on Adsorption of Rare Earth Elements by Kaolinite

Rareearthelements (REEs)werewidelyappliedtotracingthesourcesofmaterialsandtostudyingtheirevolutionprocessesinmanyfieldsofearthscienceinconsiderationoftheirsimilarityandsystematicdiffer enceinchemicalproperties .Furthermore ,lanthanidesarebothimportantprod…     

Study on Monoxide Emission Spectrometry of Rare Earth Elements Ⅰ. Determination of Sm in Rare Earth Concentrate by Dual Wavelength Method

ＳｔｕｄｙｏｎＭｏｎｏｘｉｄｅＥｍｉｓｉｏｎＳｐｅｃｔｒｏｍｅｔｒｙｏｆＲａｒｅＥａｒｔｈＥｌｅｍｅｎｔｓⅠ．ＤｅｔｅｒｍｉｎａｔｉｏｎｏｆＳｍｉｎＲａｒｅＥａｒｔｈＣｏｎｃｅｎｔｒａｔｅｂｙＤｕａｌＷａｖｅｌｅｎｇｔｈＭｅｔｈｏｄＺｈａｎｇＺａｉｚ...     

Effect of Rare Earth Elements on Exchange Performances of Cesium Ion-Sieve

The exchange performances and the distribution coefficient of Cesium Ion-Sieve (Cs-IS) for cesium and for some rare earth elements were compared. In particular, the effects of neodymium on the cesium ion exchange and the Cs^ selectivity variation on Cs-IS owing to introduction of rare earth elements into HLLW were studied. Though rare earth elements exhibit a small influence on the distribution coefficient for Cs^ ,they impair Cs-exchange capacity of Cs-IS to some extent. This interruption on the selectivity to Cs^ can be significantly eliminated provided an appropriate ratio of liquid to solid V: m is used.     

Effect of Rare Earth Elements on Kinetics of Salt Bath Vanadizing

Effect of Rare Earth Elements on Kinetics of Salt Bath Vanadizing     

Effect of Rare Earth Elements on Microwave Characteristics of CoFeZrRE Alloys with Higher Magnetic Loss

CoFeZrRe amorphous materials with higher ferromagnetic loss over microwave range were prepared by mechanical alloying (MA). The technical parameters on electromagnetic properties of the synthesizedmaterials, the microwave complex permeability dependence of material on doping with different rare earth was investigated. The results show that effects of rare earth elements on the microwave permeability characteristics of the studied materials are obvious and better performance of alloys with higher permeability and high loss is obtained at a suitable Tb content. Furthermore, reflection coefficient of one-layer absorber (1mm thick) was numerically simulated on basis of mi-crowave reflection absorption theorem. It is shown that these novel materials could be used as microwave ab-sorbers operating in GHz range.     

Effect of Rare Earth Elements on Powder Boro-Carbo-Nitriding at Low Temperature

Ｂｏｒｉｄｉｎｇｃａｎｓｉｇｎｉｆｉｃａｎｔｌｙｉｍｐｒｏｖｅｓｕｒｆａｃｅｐｒｏｐｅｒｔｉｅｓｏｆｓｔｅｅｌｓ,ａｎｄｔｈｕｓｉｓａｐｒｏｓｐｅｒｏｕｓｓｕｒｆａｃｅｓｔｒｅｎｇｔｈｅｎｉｎｇｐｒｏｃｅｓｓｗｈｉｃｈｈａｓａｌ ｒｅａｄｙｂｅｅｎｕｓｅｄｉｎｔｒｅａｔｉｎｇｓｏｍｅｄｉｅｓａｎｄｃｕｔ ｔｉｎｇｔｏｏｌｓ[1 ] .Ｈｏｗｅｖｅｒ,ｔｈｅｒｅｅｘｉｓｔｓｏｍｅｐｒｏｂ ｌｅｍｓｉｎｂｏｒｉｄｉｎｇ .Ｆｉｒｓｔｌｙ ,ｂｏｒｉｄｉｎｇｉｓｇｅｎｅｒａｌｌｙｐｅｒｆｏｒｍｅｄａｔｔｅｍｐｅｒａ…     

Effect of Rare Earth Elements on the Impact Wear Resistance of Nitrocarburizing Layers

In this paper the effect of rare earth elements on the toughness and impact wear resistance of nitrocarburiz-ing layers is studied.The experimental results show that the toughness and impact wear resistance ofRE-nitrocarburizing layers are increased significantly compared with that of conventional nitrocarburizing lay-ers.The service life of hot die for manufacturing bicycle bolts increased more than 100%.The impact wearmechanism of RE-nitrocarburizing layers is investigated by SEM as well.     

Effect of Rare Earth Elements on Thermal Fatigue Property of Low Chromium Semi-Steel

The effect of rare earth elements on eutectic carbide‘s morphology of low chromium semi-steel in as-cast state and after heat treatment was investigated, and accordingly, the thermal fatigue property of this material was studied. The results show that RE can improve the eutectic carbide‘s morphology, inhibit the formation and propagation of thermal fatigue cracks, therefore, promote the thermal fatigue property, which is more noticeable in case of the RE modification in combination with heat treatment. The optimal thermal fatigue property can be obtained when treated with 0.2% RE modification as well as normalization at 950℃ for 3h.     

Study on Electronic Structure of Rare Earth Complex with Dioxygen

The electronic structure and chemical bonding of[Ce(CO_3)_3O_2]_2~(8-) have been studied by INDO(Intermediate Neglect of Differentiated Overlap)method in this paper.The results obtained show that theHOMO of[Ce(CO_3)_3O_2]_2~(8-) is mainly composed of the anti-bonding π orbitals of the pcroxide ion(O_2~(2-))and the LUMO is mainly composed of the 4f orbitals of the Ce(Ⅳ).The peroxide ion coordinates to ceric ionby means of σ and π dative bonds.After coordination the O-O bond of the peroxide ions is strengthened.Bycomparison with cerous complexes,the contribution of the 4f orbitals to bonding increases in the ceric com-plex.     

Effect of Rare Earth Elements on Anisotropy and Microstructure of Al-Li Alloy 2195 Sheets

Aluminum-lithiumalloy 2195 is a kind of poten-tial material for innovative manufacturing of key partsin aviation and aerospace .The alloys display a superi-or strengthto weight ratio than any other conventionalaluminumalloy under the applied condition .If the al-loyis properly processed ,it can perform higher frac-ture strength in cryogenic temperature than at roomtemperature[1],so its promising future in the nationaldefense industry can be predicted definitely . Howev-er ,the alloy exhibits s…     

Effect of Rare Earth Elements on Anisotropy and Microstructure of AI-Li Alloy 2195 Sheets

For the purpose of decreasing the applied limitation resulting from the anisotropic mechanical property of Al-Li alloy 2195, this study employed a complex heat treatment process, involving the pre-tension, thermo-infiltration of the rare earth element Ce, solution treatment, and artificial aging technology. The results indicate that the infiltration of rare earth element Ce benefits the abatement of anisotropy of Al-Li alloy 2195 sheet, in contrast with that of the normal heat treatment process. The gradient of the Vickers-hardness decreases at least 50% through the thickness, and the tensile strength in the rolling direction also increases significantly. If Ce was infiltrated into the alloy under the optimum pre-deformation, the yield strength （σ0.2） increased by 30 MPa while the tensile strength （σb） enhanced by 25 MPa compared to the rare earth free samples. Meanwhile, the fractography illustrated that the fracture surface of the sample became more desirable.     

Effect of Rare Earth Elements on Erosion Resistance of Nitrocarburized Layers of 38CrMoAl Steel

Effect of rare earth elements (RE) on erosion resistance of nitrocarburized layer of 38CrMoAl steel was investigated. The results indicate that significant improvement occurs in erosion resistance of nitrocarburized 38CrMoAl steel by introducing RE during nitrocarburizing processing as compared with conventional nitrocarburizing processing. Results of mechanical testing show that both hardness and impact toughness of RE-nitrocarburizing layer of 38CrMoAl steel increase as compared with the conventional one. Optical microscopy reveals that there is improvement in the nitrocarburized layer attributed to the introduction of RE, which results in improvement in erosion resistance. Surface morphology observation of tested samples reveals that predominantly furrow-like peelings from plastic deformation are observed for RE nitrocarburizied 38CrMoAl steel, while the furrow-like peeling with initial cross crack and large grinding peelings were observed for conventionally nitrocarburized samples.     

A Quantum Chemical Study on Hexanuclear Cluster Halides of Rare Earth Elements and Their Interstitial Compounds

The electronic structures of rare earth cluster halides R(R_6X_(12)) and their interstitial compounds R_7X_(12)Zwere studied by the DV-X_(?) method (R=Sc,Y,Pr,Gd or Er;X=Cl,Br or I;Z=B,C,N,Fe,Co or Ru).Theresults show that because f electrons in empty rare earth cluster are screened,their orbitals are more difficult tooverlap each other,a deficiency of skeleton orbitals in cluster causing the system to be unstable.They are easilycondensed into chain compound R_2X_3 or R_5X_8.If a light atom of main group is embedded into octahedralcluster,bonding orbitals formed from interstitial atom and rare earth cluster strengthen clusterskeleton bond in the system to reach structural stability.If embedded atom belongs to transition metal,bondingorbitals composed of that of interstitial atom and rare earth cluster take the place of original cluster skeletonorbitals to form heteronuclear metal cluster (or double-coordination compound).     

Effect of Rare Earth Elements on Austenite Growth Dynamics of Steel 9Cr2Mo

ＥｆｆｅｃｔｏｆＲａｒｅＥａｒｔｈＥｌｅｍｅｎｔｓｏｎＡｕｓｔｅｎｉｔｅＧｒｏｗｔｈＤｙｎａｍｉｃｓｏｆＳｔｅｅｌ９Ｃｒ２ＭｏＹａｎｇＱｉｎｇｘｉａｎｇ；ＷａｎｇＡｉｒｏｎｇ；ＧａｏＭｉｎｇ；ＷｕＨａｏｑｕａｎ；ＧｕｏＴｉｅｂｏＧａｏＭｉing;Ａｂｓｔ...     

Effect of Rare Earth Elements on Isothermal Transformation and Microstructures in 20Mn Steel

The effect of rare earth elements on the isothermal transformation and microstructures in 20Mn steel is in-vestigated by means of metallography and dilatometry.Rare earth elements decrease both the incubation periodof pro-eutectoid ferrite and the rate of pearlitic transformation.In addition,rare earth elements play a role ofreducing needle-like ferrite and the amount of pearlite,densifing the lamellar space of pearlite and enhcingsegregation of carbide in granular bainite.It is suggested that rare earth elements may decrease the interfacialenergy of grain boundary and interphase,hinder the diffusion of carbon atoms and form rare earth carbides withhigh melting point which reduce the carbon content in austenite.     

Effect of Rare Earth Elements on Thermal Fatigue of High Ni－Cr Alloy Cast Iron

ＥｆｆｅｃｔｏｆＲａｒｅＥａｒｔｈＥｌｅｍｅｎｔｓｏｎＴｈｅｒｍａｌＦａｔｉｇｕｅｏｆＨｉｇｈＮｉ－ＣｒＡｌｌｏｙＣａｓｔＩｒｏｎＹａｎｇＱｉｎｇｘｉａｎｇ（杨庆祥）；ＷａｎｇＡｉｒｏｎｇ（王爱荣）；ＲｅｎＸｕｅｊｕｎ（任学军）；ＷｕＨａｏｑｕａｎ（...     

Effect of Long-term Intake of Rare Earth in Drinking Water on Trace Elements in Brains of Mice

Ｔｈｅｉｍｐａｃｔｏｆｒａｒｅｅａｒｔｈｓｏｎｅｎｖｉｒｏｎｍｅｎｔ,ｈｅａｌｔｈａｎｄｅｃｏｓｙｓｔｅｍ ,ａｎｄｉｔｓｌｏｎｇ ｔｅｒｍｂｉｏ ｌｏｇｉｃａｌｅｆｆｅｃｔｓｈａｖｅｄｒａｗｎｐｅｏｐｌｅ′ｓｍｕｃｈａｔｔｅｎ ｔｉｏｎ ,ｍａｎｙｗｏｒｋｓｈａｖｅｂｅｅｎｄｏｎｅ ,ｂｕｔｌｉｔｔｌｅｈａｓｋｎｏｗｎａｂｏｕｔｔｈｅｅｆｆｅｃｔｏｆｒａｒｅｅａｒｔｈｏｎｔｒａｃｅｅｌｅｍｅｎｔｓ[1 ] .Ｔｒａｃｅｅｌｅｍｅｎｔｓｐｌａｙａｎｉｍ ｐｏｒｔａｎｔｒｏｌｅｉｎｄｅｖｅｌｏｐｍｅｎｔ ,ｍｅｔａ…     

Study on Adsorption Behavior of Rare Earth Complexes on Nanometer-Size Titanium Dioxide with ICP-AES

Inrecentyears ,rareearthelements (REEs)havebeenwidelyusedinfunctionalmaterials ,cata lystsandotherproductsinindustry ,diagnosisreagentsofmagneticresonanceimaging (MRI)inmedicineandsomefertilizersinagricultureespeciallyinChina .However,asaresultoftheirusage ,moreandmoreREEsaregettingintotheenvironment,andalsointohumanbodyviafoodchain[1,2 ] .Itisnotclearwhetherrareearthelementsareessentialforman ,soitisveryurgenttostudythebiologicaleffectofrareearthelementsinhumanhealthandenvironment .Inthes…