Effects of Neodymium on Nitrogen Metabolism of Plantlet Loquat in Vitro

RareEarthElements (REEs)havespecialelec tricstructuresandtheeffectsonvarietiesofbiologicalactivities .REEspromotingnitrogenmetabolismhasbeenmuchreported[1～4 ] .Ourpreviouspapersstudiedlanthanumandeurioumontherootingofloquatplant letinvitro ,showingthatLaandEucanstimulatethegrowthanddevelopmentofroot ,andenhancetheac tivitiesofnitratereductase (NR)significantly[5,6 ] .ltiswellknownthatnitratereductasecatalyzesthere ductionofNO3- toNH4 .Glutaminesynthetase (GS)andglutamatedehydrogenase…     

Effect of Lanthanum on Disease Resistance Related Enzymes of Rape

Thegrowthandtheabilitytoresistdiseaseofcropscanbeincreasedbyrareearthelements (REEs)ofsuitableconcentration[1,2 ] .ReportsshowedthatsprayingREEscandecreasethediseaseindexesofin fectedplants .Zhangetalfoundthatthegrowthofapathogenofrapeformingsclerotium (Sclerotiniascle rotiorum )couldbeinhibitedbyREEsofacertaincon centration[3] .ButonlyafewreportshavestudiedthemechanismofthediseaseresistanceinducedbyREEs.EspeciallytheactivityofenzymesrelatedtodiseaseresistanceaffectedbyREEs ,aswellasthe…     

Enthalpies of Solution of Complexes of Rare Earth Nitrate with L-α-Histidine in Water

The enthalpies of solution in water of complexes of RE(NO3)3(RE = La - Nd, Sm- Lu, Y) with L-α-Histidine (His) were measured at 298.15 K. The standard enthalpies of formation of RE(His)^3 (aq) were calculated. The “tetrad effect” regularity was observed from the curve, which is the enthalpies of solution plotted against the atomic numbers of the elements in lanthanide series.     

Effect of Cerium on Expression and Activity of MMP-9 from Human Carcinoma of Bladder Cell Line

Rareearthshaveledtowidespreadinterestsinlifescience ,whilethescientistsdoresearchesdeeplyinmedicalandbiochemicalfields .Rareearthsplaypotentialrolesininhibitingcancer ,andalargenum berofscientistsdedicatethemselvestoit[1] .Thema trixmetalloproteinases (MMPs)areafamilyofatleast1 7humanzinc dependentendopeptidasesthatareca pableofdegradingalmostallextracellularmatrix(ECM)components .Theyareessentialinmanyphys iologicalprocessesandseveralpathologicalconditions ,suchastumorprogression .MMPsare…     

Structural and Magnetic Properties of the New Type of Rare Earth-Iron-Nitrogen Intermetallic Compounds

We succeed in inserting a number of nitrogen atoms into the R_2Fe_(17)and RTiFe_(11)intermetalliccompounds.The nitrides retain original Th_2Zn_(17)(or Th_2Ni_(17_)and ThMn_(12)structures,but with an increase inthe unit cell volume.The interstitial nitrogen atoms are found to have an effect of increasing the Curie tempera-ture and saturation magnetization.Moreover,a distinct effect on the magnetocrystalline anisotropy is also ob-served in these nitride compounds.Especially,NdTiFe_(11)N_(0.5)and SmTiFe_(11)N_2 have excellent intrinsic magneticproperties favourable for permanent magnet applications.     

Abstracts of Papers in Journal of the Chinese Rare Earth Society

SynthesesandCrystalStructuresofRareEarth (La ,Ho)ComplexeswithN p Tolysulfonyl β AlanineMaLufang1,WangJiange1,WangLiya1 ,LiangFupei2 ,ZhangManbo2 ( 1 .DepartmentofChemistry ,LuoyangTeacher′sCollege ,Luoyang 4 71 0 2 2 ,China ;2 .DepartmentofChemistry ,GuangxiNormalUniversity ,Guilin 541 0 0 4 ,China)Abstract:TworareearthcomplexesofN p tolysul fonyl β Alaninewiththeformulaof [Ln2 (Ts β AlaH ) 6 (H2 O) 4]n·4nH2 O (whereLn =La(1 ) ,Ho(2 ) ,Ts β AlaH =p tolysulfonyl β Al…     

Rare Earth Complexes of Aminopolycarboxylic Acid Ⅱ.Synthesis and Structure of Lanthanum Complex of Dipicolinic Acid

Complexes of the general formula,(Me_4N)_2[(Ln(HDPA)_2(DPA)]·Cl,have been synthesized,whereLn=La,Ce,Pr,Nd,Sm and H_2DPA=dipicolinic acid.Among them,the crystal structure of the La complexhas been determined by a four-circle X-ray diffractometer to a final R value of 0.080.The crystal isorthorhombic,space group Pccn with a=1.0321(1),b=1.4951(2),c=2.0766(6)nm,V=3.2044(9)nm~3,andZ=4.The rare earth ion is nine coordinated to forming a tortuous tricapped trigonal prism.     

Computer Simulation of Effect of Intergrain Exchange Interaction on Magnetic Properties of Nanocomposite Magnets

Nanocompositemagnetsareoneofcandidatesformagnetsinthenextgeneration .Inananocompositemagnet,theexistenceofmagneticallysoftgrainswithahighsaturationmagnetizationenhancestherema nence,andconsequentlyahigh (BH ) max valueisachieved[1] .Asthemagnetizationinthesoftgrainsispreventedfromtheirreversalbytheintergrainex changeinteractionbetweensoftandhardgrains ,theintergrainexchangeinteractionplaysanimportantroleindeterminingmagneticproperties .Therefore ,itscontrolisconsideredtobeakeytechnologyforobt…     

The Abstracts of Papers in the Chinese Edition of this Journal

Studies on Rare Earth-Hydroboron CompoundsⅫ. The Rare Earth Complexes of 2,2′-Bipyridine-N, N'-dioxide Containing(B_(12)H_(12))~(2-), (B_(10)H_(10))~(2-) or(B_(10)H_9NH_2COC_3H7)~- Hu Pei-Zhi(胡培植),Zhang Lun(张伦), Ji Li-Cai(季立才), ZhengXue-Wu(郑学武)(Department of Chemistry, WuhanUniversity, Wuhan 430072, China), 1990, 8, 301.Eight new rare earth complexes of 2,2'-bipyri-dine-N, N'-dioxide(bipyO_2)containing(B_(12)H_(12))~(2-),(B_(10)H_(10))~(2-) or (B_(10)H_9NH_2COC_3H_7)~- have been syn-thesized by the reaction of Ln_2(B_(12)H_(12))_3 andbipyO_2, or that among LnC1_3, bipyO_2 and     

Structural Analysis of a New Phase of BaNdMnO4

Single crystal of BaNdMnO4 with I4/mmm was synthesized by a floating zone method. A new phase of BaNdMnO4 was obtained by annealing the single crystal in a reducing atmosphere at 573 K for 10 d. The structural change was analyzed by four-circle X-ray diffractometry and transmission electron microscopy. The new phase has an orthorhombic unit cell (Fmmm) of a=0.5486(2)nm, b=0.5484(2)nm, and c=1.3059(2)nm.     

Effect of comburent ratios on combustion synthesis of Eu-doped β-SiAlON green phosphors

SiAlON phosphors doped with rare earths have attracted much attention on the application of light emitting diode(LEDs) benefitting from their outstanding thermal stability, chemical stability and broad emission band properties. In this work, Eu-doped β-SiAlON green phosphors with composition Si_(5.5)Al_(0.5)O_(0.5)N_(7.5):0.035Eu~(2+) were prepared by a highly efficient combustion synthesis(CS) method. The effect of comburent ratios(i.e., Si Al) were systematically investigated by adjusting the starting compositions of reactants. It was confirmed that the ratios of Si and Al reactants had an intense influence on the phase composition, microstructure and photoluminescence properties of as-synthesized phosphors by directly determining the systematic energy in CS. The as-prepared β-SiAlON:Eu~(2+) phosphors featured with high phase purity, uniform particle size of 3–5 μm, well-crystalline morphology and outstanding luminescent properties of green emission under UV or blue excitation were synthesized with 67.5 wt.% ratio of Si and no Al comburent.     

Computerized Simulation of the Structure of Molten DyF_3-LiF System

The structure of molten DyF_3-LiF system has been simulated by Monte Carlo method.Theradial distribution functions(RDFs)and the local structure have been obtained.It is concluded that F~- ionsdistribute closely around Dy~(3+) ions.There exist some fissures and holes between F~- ions and Li~+ ions.There are mainly two kinds of ionic types:the complex ions like DyF_n~(3-n) clusters with the central Dy~(3+) ions(the main ionic clusters are octahedral complex ions like DyF_6~(3-))and the“free”Li~+ ions.Moreover,somecomplex ions like DyF_n~(3-n) clusters are connected to one another by flourine-bridge,forming more compli-cated ionic clusters like Dy_m~(3m-n) F_n.By calculating the potential energies of all types of ions,it is concludedthat Li~+ ions have the highest potential energy in the molten system,which are current-carrying ions in theelectrolytic conductance.     

Cyclic Electrodeposition of Yb-Bi Thin Films

Recently ,Bihasattractedmuchattentionforap plicationsinvolvingfieldandcurrentsensingduetoitsextremelyhighmagnetoresistance (MR )relativetothosereportedforGMRandCMRmaterials .ThelargeMRofBiarisesfromitspeculiarelectronicstructure .Ithasasmallenergyoverlap (～38meV)betweentheLconductionandTholebands ,smalleffectivemasses(atthebandedge ,me=0 0 0 2m0 ) ,andhighmobil ities .Becauseoftheseproperties ,Bihasfrequentlybeenusedforquantumconfinementstudiesinquan tumwellandquantumwiregeometries[1] …     

Effects of Cerium on Accumulation of Anthocyanins and Expression of Anthocyanin Biosynthetic Genes in Potato Cell Tissue Cultures

The effects of Ce (Ⅳ) on callus growth, anthocyanin content, and expression of anthocyanin biosynthetic genes in callus suspension cultures of Solanum tuberosum cv. Chieftain were studied by the measurement of fresh weight, spectrophotometric assays, and semiquantitative RT-PCR. The results indicate that 0.1 mmol·L-1 Ce (Ⅳ) can promote callus growth, increase the accumulation of anthocyanins, and enhance the expression of five anthocyanin biosynthetic genes (CHS, F3H, F3′5′H, DFR, and 3GT) most efficiently. At high concentrations of 1 mmol·L-1, Ce (Ⅳ) partially inhibits callus growth and at 2 mmol·L-1 eventually lends to cell death. The results show that Ce(Ⅳ) can induce the expression of anthocyanin biosynthetic genes to produce and accumulate anthocyanins and increase the yield of anthocyanins.     

Synthesis of ZnO∶Dy Nanopowder and Photoluminescence of Dy~ (3+) in ZnO

Thedevelopmentofadvanceddisplayandlight ing technologysuchasfield emissiondisplays(FEDs)andplasmadisplaypanels(PDPs)requiresphosphor whichhasahighefficiencyandcoloredluminescence films.Zincoxide(ZnO)infilmandpowderformsis oneofthemostefficientoxide basedwideband gap phosphormaterials.ZnOischemicallystableandhas moderateconductivitycomparedwithconventionalsul fidephosphormaterials.RE dopedsemiconductorhas applicationsinactivelayers,forexample,thinfilm electro luminescencedevices[1],optoelec…     

Effect of Rare Earth on Microstructure of γ-TiAl Intermetallics

The rare earth (RE) elements (Ce, La) were added to binary Ti-47% Al alloys (atomic fraction) by Induction Skull Melting. The element Ce of 1.0 atomic percent was added individually, and La of 0.2 atomic percent was added individually. This article studied the influences of rare earth metal (Ce, La) on microstructure of as-cast TiA1 based alloy by XRD, SEM, EMPA and TEM measurement methodology. The results show that most of rare earth-rich phases (AlCe, Al-La) are uniformly distributed in grain boundary in the shape of discontinuous network, and some particles of rare earthrich phases within the grains are mainly ellipsoids. In addition, rare earth element can obviously refine the grain size and the lamellar thickness of as-cast TiAl based alloy samples. The grain size of Ti-47Al-1.0Ce-0.2La alloy reaches about 30～80μm, and the lameUar thickness of its γ phase and α2 phase are less than 200 and 20nm, respectively.     

Effect of Interstitial Atom Nitrogen on Properties of RE2Fe17 Compounds

The electronic structure and atomic magnetic moments of clusters NdFe6, NdFe6N3 and Fe8 with a dumbbell atom-pair in rare earth-transition element compounds NdEFe17Nx(x=0, 3) were studied by spin-polarized MS-Xα method. The results are as follows: There are three negative exchange couplings between Fe(c) and Fe(f) atoms in Nd2Fe17, which occur at their odd parity orbitals. Compared to the results of α-Fe calculated by the MS-Xα method, the low Curie temperature of compounds RE2Fe17 can be explained satisfactorily. (2) There is only one weaker negative exchange coupling orbital leaving in between Fe(c) and Fe(f) sites in Nd2Fe17N3. These results may be helpful for understanding the effect of interstitial atom M(M=N, H or C) in Fe2Fe17Mx on Curie temperature. The other key factors affecting the Fe-Fe exchange coupling in Fe2Fe17 compounds were also discussed.     

Effect of Additive Cu10Sn Alloy on Sintering Behavior of Elemental Powders in Composition of 465 Stainless Steel

 The addition of Cu 10Sn alloy for developing the high strength 465 maraging stainless steel from elemental powders was studied. The sintering parameters investigated include the sintering temperature, the sintering time, and the mass percent of Cu 10Sn. For vacuum sintering, effective sintering occurs at temperature between 1 250 ℃ and 1 300 ℃. The maximum sintered density was achieved at 1 300 ℃ for 60 min with 3% (in mass percent) Cu 10Sn alloy. More than 3% (in mass percent) Cu 10Sn content and temperature above 1 300 ℃ caused slumping of the samples. A maximum density of 74 g/cm3 was achieved with 3% (in mass percent) Cu 10Sn content at a sintering temperature of 1 300 ℃ for 60 min. A maximum ultimate tensile strength (UTS) of 517 MPa was achieved with 3% (in mass percent) Cu 10Sn content. With content higher than 2% (in mass percent) Cu 10Sn, a maximum increase in the density was observed. The fracture morphologies of the sintered samples are also reported.     

Influence of Rare Earth Elements on Luminescent Properties of Y_2SiO_5∶Tb

Various types of multicomponent oxide phosphorshave been widely studied for the applications in dis-play techniques , such as high definition television(HDTV) ,projection television (PTV) and flat paneldisplays (FPD) .Since the beginning of the 1990s ,anewtype of flat panel display device ,field emissiondisplay (FED) has been developed .In this device ,the phosphors are excited bythe cathode rays withlowvoltage ( <5 kV) and high current density . Due tothese excitation conditions ,the ge…     

Synthesis of rare earth metal-organic frameworks （Ln-MOFs） and their properties of adsorption desulfurization

The rare earth metal-organic frameworks(Ln-MOFs) materials,Ln(BTC)(H2O)·(DMF),were synthesized using the rare earth metal(Ln=Sm,Eu,Tb,Y) and 1,3,5-trimesic acid(BTC) as a metal ion center and ligand,respectively.X-ray diffraction(XRD) and infrared spectroscopy(FT-IR) were employed to characterize the Ln-MOFs structural features.The property of adsorption desulfurization of Ln-MOFs materials was evaluated with thiophene/n-octane as model oil.The results showed that Ln-MOFs with rare earth metals Sm,Eu,Tb and Y had perfect crystalline and good adsorption desulfurization ability.Y(BTC)(H2O)·(DMF) material had a comparatively better activity for the adsorption desulfurization with desulfurization rate up to 80.7% and the sulfur adsorption capacity was found 30.7 mgS/g(Y-MOFs).The Ln-MOFs materials had excellent reusability.