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1.
Anderson结构稀土钼铬多金属氧酸盐的合成与表征   总被引:2,自引:0,他引:2       下载免费PDF全文
A new kind of Anderson-type chromium-molybdates containing the rare earth elements are synthesized, which have the general molecular formula of (NH4)6[CrMo5Ln(OH2)2O24H6xH2O (Ln=La,Ce,Pr,Nd,Sm,Gd and Yb). The components of these heteropoly complexes are determined by chemical elemental analysis, ICP and TG-DTA. And IR, UV, ESR,XPS and 1H NMR are also applied to characterize the complexes as well. The results indicate that the structures of these complexes are Anderson B type and the rare earth elements are in the inner sphere of the heteropoly salts. The thermal stabilities of these complexes studied by TG-DTA show that the range of pyrolysis temperature is between 490℃ and 500℃.  相似文献   

2.
纳米Mn-Zn铁氧体的制备和研究   总被引:10,自引:0,他引:10  
Nanosize manganese zinc ferrites were fabricated by hydrothermal precipitation route using Fe2(SO4)3, ZnSO4·7H2O, MnSO4·H2O as material, then some calcinated at 500 ℃ and studied by XRD, TEM, IR and VSM. The results showed that the products were spinel crystal structure and uniformly sized nanoparticles (15~25 nm) with little aggregation. The analysis of IR showed that the superficial water can be eliminated, but that was embedded in crystal lattice can not be removed by calcinating. The effect Zn content x on the lattice (a) of nanosize Mn1-xZnxFe2O4 was also discussed. The lattice of nanosize Mn1-xZnxFe2O4 decreases with x increasing; and its value deviated the standard lattice (a0) of normal size manganese zinc ferrites. A lot of water was absorbed during the hydrothermal process owing to the large surface of nanosize particles. The change of magnetic properties of MnxZn1-xFe2O4 with x increasing was studied: nanosize MnxZn1-xFe2O4 particles synthesized by us exhibited peculiar magnetic properties curve with Zn content (x) increasing, Superparamagnetic behaviors of the synthesized ZnFe2O4 samples were confirmed by magnetic characterization, which can be explained by the difference between the distribution of the metal ions (Mn2+, Zn2+ and Fe3+) among the tetrahedral (A) and the octahedral (B) sites of nanosize ferrite and that of bulk ferrite.  相似文献   

3.
The title compound has been prepared and characterized by elemental analyses, infrared and raman spectra, and thermal analyses. The crystal structure of Bis [di(N′-ethyl-N-piperazinly-carbodithioato-S,S′) Zinc(Ⅱ)] complexes, [Zn2(S2CNC4H8NC2H5)4], was determined by X-ray diffraction methods. The compound crystallizes in Monoclinic system, space group P21/c, with lattice and some related parameters a=0.886(18), b=1.955(4), c=1.196(2) nm, β=106.03(3)°, V=1.991 3(7) nm3, Z=2, Mr=888.12, Dc=1.481 g·cm-3, F(000)=928, R=0.054 3 and wR=0.227 6. In crystal structure of the binuclear zinc complexes is built up of centro-symmetric dimeric entities. The coordination sphere of zinc(Ⅱ) ions is best described as a distorted tetragonal-pyramid. The IR spectral data are in agreement with the structural data. The thermal analytical data indicate that it decomposed completely at the temperature of 652.5 ℃, leaving Zn. CCDC: 286177.  相似文献   

4.
微波辐射固相法合成缩二脲铜配合物   总被引:5,自引:0,他引:5  
The copper(Ⅱ) complexes of biuret have been synthesized by solid phase reaction with microwave irradiation. The compositions and structures of the complexes are characterized by elemental analysis, molar conductance, in-frared spectra, electronic spectra, magnetic susceptibility, thermogravimetric and differential thermal analysis, X-ray powder diffraction. The two complexes have the compositions of [Cu(bi)2]Cl2(A) and [Cu(bi)2](NO3)2(B)(bi=NH2CONHCONH2) and the molecular formulae of CuC4H10O4N6Cl2 and CuC4H10O10N8, respectively. The molar conductance data show that the complexes are 1∶2 electrolyte. Infrared spectra of the complexes show oxygen atoms have been coordinated with divalent copper ion. The thermal decomposition processes of the complexes show that the final residues are all cupper oxide. The results of indexes to the X-ray powder diffraction data indicate that the crystal structure of the complexes belong to monoclinic system, the lattice parameters are: a=0.6976nm,b=1.1546 nm,c=2.1689nm,β=96.80°,V=1.7346nm3 for A; and a=0.7096nm,b=1.1359 nm,c=2.1002 nm,β=97.05°,V=1.6800nm3 for B, respectively.  相似文献   

5.
The protonation constants of the macrocycle H2L1 (c-meso-2,4,4,11,13,13-hexamethyl-1,5,10,14-tetraazacyclooctadecane-N,N"-diacetic acids)were determined potentiometricly and by computer fitting in 0.5 mol·L-1 KNO3 solution at 25±0.1℃, 30±0.1℃ and 40±0.1℃. The stability constants of the 1∶1 complexes of H2L1 with La3+, Nd3+, Sm3+, Eu3+, Gd3+, Dy3+, Yb3+ were determined by the same method at 40±0.1℃. The ΔH、 ΔS and ΔG of the coodination reaction of H2L1 with H+ in the aqueous solution were found.  相似文献   

6.
5-Chloro-2-methoxybenzoates of heavy lanthanides and yttrium were obtained as di- or tetrahydrates with a metal to ligand ratio of 1:3 and general formula: Ln(C8H6ClO3)3nH2O, where n=2 for Ln=Tb, Dy, Y and n=4 for Ln=Ho, Er, Tm, Yb, Lu. The complexes were characterized by elemental analysis, IR and FIR spectra, thermogravimetric studies, X-ray diffraction and magnetic measurements. The carboxylate group appears to be a symmetrical, bidentate, chelating ligand. All complexes are polycrystalline compounds. Their thermal stabilities were determined in air and in nitrogen atmospheres. When heated they dehydrate to form anhydrous salts which next in air are decomposed to the oxides of the respective metals while in nitrogen to the mixtures of carbon and oxides or carbon and oxychlorides of respective metals. The complexes are more stable in air than in nitrogen. The solubilities of yttrium and heavy lanthanide 5-chloro-2-methoxybenzoates in water at 293 K are of the order of 10–3 mol dm–3 The magnetic moments of the complexes were determined over the range 77–298 K. They obey the Curie–Weiss law. The values of μeff calculated for all compounds are close to those obtained for Ln3+ by Hund and Van Vleck. The results indicate that there is no influence of the ligand field of 4f electrons on lanthanide ions and the metal ligand bonding is mainly electrostatic in nature. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

7.
Cu1-xAgxI(x=0.5~0.6)纳米微粒的制备与表征   总被引:1,自引:0,他引:1  
In the presence of PVPK30,Cu1-xAgxI nanoparticles were prepared by ion exchange reaction.The product was characterized by FT-IR,XRD,TEM,EDS and SPS,respectively.It was found that the value of x is ap-proximately 0.5~0.6and the average diameter of the nanoparticles is 10~20nm.The product shows surface photovoltage property of semiconductor and the existence of Cu+ greatly enhances the separation efficiency of photoinduced electron-hole pairs.Meanwhile,SPS of Cu1-xAgxI nanoparticles with different X (Ag/I)value had been investigated. The results show that when X is 0.5~0.576, the SPS intensity of Cu1-xAgxI nanoparticles is highest.  相似文献   

8.
The novel copper(Ⅱ) complex with 2-oxo-propionic acid benzoyl hydrazone and pyridine ligands, Cu(C10H8N2O3)·(C5H5N)·(H2O) (C10H8N2O32- is the dinegative ion of 2-oxo-propionicacid benzoyl hydrazone), has been synthesized and characterized by elemental analysis and IR. The crystal structure of the title complex was determined by single crystal X-ray diffraction technique. Complex crystallized in the triclinic space group P1 with a = 0.729 08(10) nm, b= 1.020 01(14) nm, c= 1.126 28(15) nm, α = 71.644(2) °, β = 80.437(2) °, γ = 89.160(2)°, V= 0.78328(18) nm3, Z= 2, Dc= 1.547 Mg·m-3, μ(Mo) = 1.417 mm-1, F(000) = 374. The final R1 = 0.030 6, wR2= 0.084 2 for 2 992 observed reflections [I≥2σ(I)] out of 3357 unique reflections. In this complex, copper(Ⅱ) ion is square-pyramidally coordinated by two oxygen atoms and one nitrogen atom of tridentate C10H8N2O32- ligand, one nitrogen atom of the pyridine ligand, and one oxygen atom of water molecule with the oxygen atom of water molecule locating at the apical position. The analysis of the crystal structure indicates that the complex has a one-dimensional chain structure, which is formed by intermolecular hydrogen bonds. CCDC: 222656.  相似文献   

9.
钾的N-酰化牛磺酸配合物的合成、表征及其晶体结构   总被引:3,自引:0,他引:3  
The title complex(K(C9H13NO5S2)(H2O)) was synthesized by the reaction of p-tolysulfonyl chloride, taurine and potassium hydrate in water-methanol-ethanol solution. The crystal structure was determined by X-ray diffraction method and the chemical formula weight of the complex is 336.44. The crystal structure of the title complex belongs to orthorhombic space group Pbca and cell parameters: a=0.853 31(12) nm, b=0.820 42(12) nm, c=3.989 4(6) nm. V=2.792 8(7) nm3, Z=8, Dc=1.600 g·cm-3, μ=0.699 mm-1, F(000)=1 400. The compound is an one-dimension chain complex of infinite length which are connected with hydrogen bond and bridging coordination water. The difference and same of the complexes were discussed. CCDC: 244938.  相似文献   

10.
N3- is a kind of ligand with very strong power for coordination, and is able to bind with many kinds of metal ions or metalloproteins. The metal ions in metalloproteins usually locate at the active site of them, and the combination of other chemical compound(s) to them will cause great influence on the structure and function of them. In addition, the combination can also provide information of the structure of the active site of the enzymes, and that of the higher-order structure of the enzyme. In this paper, we studied the interaction between N3- and PPOⅡ from Nicotina Tobacco by the determination of changes in enzymatic activity, UV-Vis, fluorescence spectra and FT-IR. The results showed that N3- can activate PPOⅡ with a near linear increase in enzymatic activity to the concentration of N3- when the [N3-]/[PPOⅡ](molar/molar) is less than or equal to 1.0, and that the enzymatic activity begins to decrease from 1.0 to 4.0; N3- didn’t coordinate directly with Cu2+ in the active site, but may interact with the side chain groups with positive charges, and further resulted in the increase in α-helix and the slightly decrease in β-turn, random coil and extended chain; the Cu2+ may locate deeply in the inner part of PPOⅡ, and coordinates strongly with nitrogen atoms in imidazole of histidine; N3- can quench the fluorescence of PPOⅡ, and make the microenvironments of Trp residues more polar after the interaction between N3- PPOⅡ.  相似文献   

11.
Zusammenfassung Für 14 Elemente wird eine universelle Methode beschrieben. Durch Zusatz von Lanthan und Cäsium werden die physikalischen, chemischen und Ionisations-Störungen in der Flammen-AAS ausgeschaltet. Es wird gezeigt, daß diese Methode für sehr unterschiedliche Stoffe mit Erfolg angewendet werden kann, und gleichzeitig die Genauigkeit des Routinemeßverfahrens nicht beeinträchtigt wird. Nur in Ausnahmefällen muß die Additionsmethode benutzt werden.
Determination of calcium, magnesium, strontium, potassium, sodium, lithium, iron, manganese, chromium, nickel, copper, cobalt, zinc and cadmium by flame AASA universal method for the analysis of waters, coals, ashes, ores, rocks, building materials, metals and similar samples
Summary A universal method is described for 14 elements. By addition of lanthanum and caesium the physical, chemical and ionization interferences in the flame AAS are eliminated. It is demonstrated that this method can be applied successfully for very different materials and simultaneously the precision of the standard measuring method is not affected. Only in exceptional cases the addition method has to be applied.


Herrn Prof. Dr. W. Schuhknecht, dem langjährigen Leiter des Zentrallabors der Saarbergwerke AG (1948–1972) zum Gedenken

Für die sorgfältige Durchführung von Säure- und Schmelzaufschlüssen sowie seine nützlichen Hinweise bei der Korrektur des Manuskriptes möchte ich Herrn Lothar Kiefer meinen besonderen Dank aussprechen.  相似文献   

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Using a recently developed procedure for optimizing parameters for semiempirical methods,1 PM3 has been extended to a total of 28 elements. Average ΔHf errors for the newly parameterized elements are Be: 8.6, Mg: 8.4, Zn: 5.8, Ga: 14.9, Ge: 11.4, As: 8.5, Se: 11.1, Cd: 2.6, In: 11.3, Sn: 9.0, Sb: 13.7, Te: 11.3, Hg: 6.8, Tl: 6.5, Pb: 7.4, and Bi: 10.9 kcal/mol. For some elements the paucity of data has resulted in a method, which, while highly accurate, is likely to be only poorly predictive.  相似文献   

15.
<正> The title com pound (HHOMP) has been synthesized with the pho-toinduced condensation of acetone and pyrrole in the presence of iodoaromatic hydrocarbons, and its molecular and crystal structures have been determined by X-ray analysis. C28H36N4, Mr = 428. 63, triclinic; space group P1; a =10. 165(3), b = 10. 185(2), c=13. 012(3)(?); α=85. 41(2), β=67. 84(2), γ= 89. 75(2)°; V = 1243 (?)3; Z = 2; D = 1. 145g. cm-3; μ= 0. 635cm-1; F (000) = 464. Although the HHOMP molecule twists, it is found that the four nitrogen atoms are still in a plane.  相似文献   

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