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1.
Therearealotsofreportsaboutthepoly merizationofacrylonitrile (AN) [1~ 3] .Intheradicalpolymerization ,usuallyitisinitiatedbybenzoperoxide ,K2 S2 O4 Na2 S2 O3,Fe2 + H2 O2 andsomeorganiccompounds .There portsonorganolanthanidesassingle componentcatalystswasrarelyinlitera…  相似文献   

2.
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.  相似文献   

3.
A new stripping agent N,N-dimethyl-3-oxa-glutaramic Acid (DOGA) was used in TRPO process to simplify the TRPO process. The structures of the complexes of the DOGA with Eu(Ⅲ), Nd(Ⅲ), La(Ⅲ) were characterized with extended X-ray absorption fine structure spectroscopy (EXAFS), infrared spectra (IR) and mass spectra (MS). The molecular formula of the complexes of Eu(Ⅲ) and Nd(Ⅲ) is deduced to be M(DOGA)3, and only La(Ⅲ) can form the complex HM(DOGA)4 under condition of high consistency of the DOGA. The coordination number of Ln(Ⅲ) in the complexes is 8, and all of coordinated donor atoms are O atoms. For Eu(Ⅲ), Nd(Ⅲ), the coordination numbers of O atom in the first coordination shell is 6 and the average coordination bond lengths of Ln-O are 0.240 nm, 0.244 nm respectively, while the numbers of the second O shell are 2.4, and the average coordination bond lengths of Ln-O are 0.260 nm, 0.262 nm. For La(Ⅲ), the coordination numbers of O atom in the first coordination shell is 6 and the average coordination bond lengths of La-O are 0.258 nm, while the number of O atom in the second coordination shell is 4.4, and the average coordination bond length of La-O is 0.28 nm. The results of IR and MS show that there is no water coordinating with Ln(Ⅲ) in the complexes.  相似文献   

4.
5.
The polymeric ligand PBIa (functionalized polybenzimidazole containing β-diketone side group) was successfully synthesized via the reaction of polybenzimidazole (PBI) with 3-Br-acetylacetone in DM SO solvent using Nail as the deprotonation reagent. Its corresponding polymeric complexes of Dy^3+ and Gd^3+ were prepared and characterized by FT-IR, ^1H NMR, molar conductance measurements, and thermal analysis. The photoluminescence properties and the probable mechanism of the Dy and Gd complexes were studied. The measurement and analysis of the thermal properties showed that these were thermal stable.  相似文献   

6.
The species and their formation constants in the ternary systems were obtained by the Scogs2 software from potentiometric titration data. The Comics software was used to calculate the distribution of species in the ternary systems.MLXH, MLXH2 and MLXH3 are the common species in these systems. The coordination behaviors of the rare earths are very similar and their stability is closely matched. The ternary rare earth complexes are more stable than the corresponding ternary complexes of calcium. The ternary zinc complex with glutamine as the secondary ligand is more stable than the corresponding complexes of rare earths, but the ternary complex with alanine as the secondary ligand shows an. inverse trend.The distributions of species in the ternary systems vary with pH changing. A prediction can be made that exogenous rare earths can affect the species of Ca and Zn in human body.  相似文献   

7.
Ingeneral,hydroximicacids (RCON HOH)areweakorganicacids .ThisclassoforganiccompoundscontainingthereactivegroupCONHOH ,knownasthehydroximicacids,havebeenwidelystudiedbyorganicchemists.Thehydroximicacidsarechelateligandsformanymetals .Theyarewidelyusedaschel…  相似文献   

8.
Greatinteresthasbeenarousedinthestudyofcomplexesofrareearthsaltswithaminoacidsbecauserareearthionspossesssomespecialfunctionsinbiochemistry .Theycanbeusedasaprobetolabelthecalciumion .Moreover,aminoacidsarethestructureunitofproteins .Gaoandcoworkersrece…  相似文献   

9.
As well known, molten salt electrolysis was wide ly used for the production of rare earth metals andtheir alloys. And, phase diagrams are the most impor tant data for fused electrolytes. Dealing with the bina ry phase diagrams relating to rar…  相似文献   

10.
稀土与L-亮氨酸、咪唑三元配合物的合成及抑菌作用研究   总被引:2,自引:0,他引:2  
陈芳  胡珍珠  石鹤  杨水金 《稀有金属》2005,29(3):311-314
在乙醇介质中,用氯化稀土盐与L亮氨酸、咪唑反应合成了稀土三元配合物[RE(Leu)3Im(H2O)]Cl3·2H2O(RE=La,Dy,Y;Leu L亮氨酸;Im咪唑)。通过化学分析、元素分析确定了配合物的组成;并利用摩尔电导率测定、IR,UV及TG DTG等对配合物进行了其配位行为和热分解机制的研究;抑菌实验表明该类配合物对大肠杆菌均具有不同程度的抑制作用,以ρ(配合物)=10g·L-1用药,24h后对大肠杆菌的菌落抑制率均为100%。  相似文献   

11.
Thedesignandsynthesisofstablelan thanidecomplexesareofgreatimportancefortheinvestigationofthepropertiesandapplica tionsoflanthanidecomplexes .Macrocyclicoracyclicligandswithmultidentatedonoratomsusuallyformstablecomplexeswithlanthanidecations .Thesizeof…  相似文献   

12.
Thepropertythattherareearthbasedhy drogenstoragealloyscanabsorb/desorbalargeamountofhydrogenatroomtemperaturehasbeenusedsuccessfullyforhydrogensepara tion ,purification ,andtransportation .Intheapplications ,inordertoavoidproblemssuchastheobstructiontogas…  相似文献   

13.
The thermodynamic optimization of the Sn-Y and Mg-Sn-Y systems was critically carried out by means of the CALPHAD(CALculation of PHAse Diagram) technique. In the Sn-Y system, the solution phases(liquid, bcc, bct and hcp) were described by the substitutional solution model. The compound Sn3Y5, which has a homogeneity range, was treated as the formula(Sn, Y)3(Sn, Y)2Y3 by a three-sublattice model in accordance with the site occupancies. In the Mg-Sn-Y system, the liquid phase was treated as the formula(Mg, Sn, Y, Mg2Sn) using an associated solution model, and bcc, bct and hcp were treated as the formula(Mg, Sn, Y). The compound Sn3Y5 was treated as the formula(Sn, Y, Mg)3(Sn, Y, Mg)2Y3. The ternary compound MgSnY was treated as stoichiometric compound. A set of self-consistent thermodynamic parameters of the Mg-Sn-Y system was obtained. The projection of the liquidus surfaces and the reaction scheme of the Mg-Sn-Y system were predicted.  相似文献   

14.
The two compounds of [Ln(2-FBA)3·2,2'-bpy]2 (2-FBA=2-fluorobenzoato, 2,2'-bpy=2,2'-bipyridine, Ln=Eu(1), Dy(2)) were synthesized and their structures were determined by X-ray diffraction method. Crystallized complexes 1 and 2 are isomorphous, monoclinic system with P21/n space group. The two complexes are binuclear molecule with an inversion center. The two lanthanide ions are linked by four bridged 2-FBA ligands and each lanthanide ion is further bonded to one chelated bidentate 2-FBA ligand and one 2,2'-bipyridine molecule. The coordination number of metal ion is eight. The europium complex exhibits strong red fluorescence. 5D0→7Fj (j= 1~4) transition emission of Eu3 ion was observed.  相似文献   

15.
SynthesisandCharacterizationofLn(NO3)3PhenFuTernaryComplexesLinJiyun(林纪筠),MaDejian(马德建)(DepartmentofChemistry,EastChinaNorm...  相似文献   

16.
Byaddingtraceamountoflanthanum(0 0 2 4% ) ,themicrostructureoftraditionalSn6 0 Pb40solderalloyishomogenized ,thatis ,thecoarseSn richhalowhichsurroundstheprimaryPb richphaseisdepressedobviously .Asaresult,thehigh temperaturetensilestrengthofSn6 0 Pb40solderalloyincr…  相似文献   

17.
Rare Earth Doping Effects on Properties of Ceria-Zirconia Solid Solution   总被引:1,自引:0,他引:1  
Ce0.6Zr0.3RE0.1O2(RE=Y, La, Pr, Tb)solid solutions were prepared by co-precipitation technique and characterized by a series of methods. XRD and FT-Raman results show that Ce0.6Zr0.3RE0.1O2 has cubic fluorite structure. The different dopant ion radii bring different effect on the cell parameter of Ce0.6Zr0.3RE0.1O2. The X-ray photoelectron spectroscopy (XPS) results show that the binding energy of Ce3d, Zr3d and O1s for Ce0.6Zr0.3RE0.1O2 rises compared with that for Ce0.6Zr0.4O2, indicating that dopant elements change chemistry environment of solid solutions which is available to improve redox performance. Compared with Pd/Ce0.6Zr0.4O2, doping Y and La does not change air/fuel (A/F) characteristic of TWCs, but doping Pr and Tb widens A/F operating window and makes HC, CO and NO have higher conversion. The light-off temperature of Pd/Ce0.6Zr0.3La0.1O2 is corresponding to that of Pd/Ce0.6Zr0.4O2. However, the light-off temperatures of Pd/Ce0.6Zr0.3M0.1O2 (M=Y, Pr, Tb) are lower than that of Pd/Ce0.6Zr0.4O2, which keep much lower after high temperature treatments. Among Pd/Ce0.6Zr0.3RE0.1O2, Pd/Ce0.6Zr0.3Tb0.1O2 represents wider A/F operating window, higher conversion, lower light-off temperature and better high-temperature resistance.  相似文献   

18.
Recently,photodegratation of various organiccontaminants with powdered semiconductors as cata-lysts has received much attention for their potential inthe utilization of light energy.TiO2is one of the mostwidely used photocatalysts due toits relatively nontox-ic,high activity,strong oxidizing property,and excel-lent stability.However,some weaknesses such as poormechanic strength,compressive strength and thermalstability have li mited its industrial applications.Therefore,it is necessary to i mp…  相似文献   

19.
The polymerization of dimethylaminoethyl methacrylate (DMAEMA) catalyzed by the 1-cyclopentylindenyl lanthanide (Ⅱ) complex (1-C5H9C9H6)2Yb (THF)2 was investigated. The results indicated that the complex (1- C5H9C9H6)2Yb (THF)2 as a single component catalyst showed high activity. The conversion of the polymerization and the molecular weight of the polymer were affected by temperature, time, amount of catalyst and solvent in the polymerization process. The catalytic activity of (1-C5H9C9H6)2Yb (THF)2 enhanced significantly when a small amount of polar solvent THF was added into the polymerization system in which toluene was selected as the solvent. The optimal temperature of polymerization was about 0 ℃. Other modified substituted indenyl lanthanide (Ⅱ) complexes also showed good catalytic activity. The order of catalytic activity of the complexes was as follows: (1-C5H9C9H6)2Sm(THF)≈ (1- C2 H5 C9H6 )2 Sm(THF)2 〉 (1 -C5 H9 C9 H6 )2 Yb(THF)2 〉 (1 -PhCH2 C9 H6 )2 Sm(THF)2. The steric regularity of p oly (dimeth- ylaminoethyl methacrylate) (PDM AEM A) was characterized by 1H NM R spectra. The polymerization provided syndio- tacticity-rich PDM AEM A. The molecular weight and the molecular weight distribution of PDM AEM A were measured by gel permeation chromatography.  相似文献   

20.
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