New Environment-Friendly Approach for Bastnasite Metallurgic Treatment (I): Extraction of Tetravalent Cerium from Sulphuric Acid Medium with Di(2-ethylhexyl) Phosphoric Acid

Bastnasiteisamainsourceofrareearthproducts inwhichCeO2/REOisabout50%.Atpresent,a cidity leachingcombinedwithalkali conversion method[1]iscommonlyusedinthebastnasitetreat ment.Thismethodisunfriendlytotheenvironment becausetheradioactiveelementofthoriuman…     

柴达木盆地天然气中稀有气体同位素特征

为了确定柴达木盆地勘探新层系，测试并分析了该盆地5个油气田的8个天然气样品的氦、氩同位素比值，探讨了其在大地构造背景、大地热流和气源方面的示踪意义。研究结果如下：①柴达木盆地8个天然气样品³He/⁴He值分布在2.0×10^-8～5.48×10^-8的范围，总体平均为3.7×10^-8，均在10^-8量级，体现了典型的壳源成因氦同位素的特征。②据³He/⁴He计算的大地热流值较低，分布于41.2~48.2 mW/m²之间，平均44.9 mW/m²，低于东部地区大地热流平均值73 mW/m²，表明该盆地具有较稳定的构造背景。③根据天然气⁴⁰Ar/³⁶Ar的年代积累效应，结合烃源岩分布特征推测，柴达木盆地东部凹陷区伊克雅乌汝构造伊深1井天然气应源于上第三系；西部坳陷区尕斯油田尕斯8-6井和尕斯475井天然气应源于下第三系；碱山构造碱1井天然气应源于侏罗系，碱山构造碱2井的天然气应源于上第三系；北缘块断带南八仙油气田仙试1井的天然气应源于侏罗系；南八仙油气田仙试8井和马北构造马北1井的天然气可能主要源于侏罗系。     

Shape-Controlled Synthesis and Upconversion Luminescence of Y2O3:Yb, Er Microstructures

The Y2O3: Yb3 , Er3 microstructures were fabricated by a hydrothermal method without surfactants.The microstructures structure was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM,KYKY 1000B).The up-conversion luminescence spectra were studied under 978 nm laser diode excitation.In Yb3 and Er3 codoped Y2 O3 microcrystals, the relative intensity of green emission became stronger as the morphology of sample changed from wires to films.     

稀土对生物机体剂量效应机理的研究进展

综述了稀土元素对生物机体剂量效应的机理 ,从稀土对细胞质膜、细胞周期及细胞凋亡、Ca M水平调节的作用到对蛋白质、DNA的影响等不同层次和水平进行了探讨 ,以期为稀土在生物学领域的进一步广泛应用奠定理论基础     

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…     

Hydriding and Dehydriding Characteristics of Mechanically Alloyed LaMg_(17) Ni Composite Material

Magnesiumandmagnesiumalloyshavebeenin vestigatedashydrogenstoragematerialsforseveralde cadesbecausefarmorehydrogenbyweightcanbestoredinthemthaninmostoftheothercurrentlyknownhydrogenstoragealloys .Moreover ,thehighnaturalabundanceofMg ,itslightmassandenviron mentalcompatibilitypotentiallymakemagnesiumoneofthemostprospectivecandidatesforfuturehydrogenstoragematerials .Unfortunately ,thepracticalappli cationofMganditsalloyshasbeenlimitedonlytocertainstoragedevicebecauseoftheirpoorhydriding dehydr…     

Composition Range of Amorphous Mg-Ni-Y Alloys

Based on the thermodynamic point of view, a method for predication of the composition range of amorphous ter-nary alloys was proposed. The composition range of amorphous ternary alloys is determined by the comparison of the excess free energy of the amorphous alloy and the free energy of competing crystalline states. The free energy is extrapolated from the data of three binary alloys by using Toop‘s model. The method was applied to predict the composition range of amor-phous Mg-Ni-Y alloys. The theoretical results are in good agreement with the available experimental results. It indicates that the present method can be used to predict the composition range for amorphous ternary alloys.     

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…