首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Study on the extraction and separation of rare earth with new extractants is important in the rare earth chemistry and nuclear reprocessing. In this work, the extraction of Ce(Ⅲ) with N,N,N′,N′-tetrabutylmalonamide (TBMA) in toluene from nitrate media has been investigated. The effect of the concentration of nitric acid, TBMA and salt-ing-out agent (LiNO3) and also the temperature on the distribution ratios was examined. The stoichiometries of the extracted complexes were determined to be Ce(NO3)3·3TBMA and Ce(NO3)3·4TBMA, respectively. The ap-parent extraction constants and the enthalpy of the extraction were calculated based on the extraction data, which are logKex1=3.97, logKex2=4.75 and ΔrHm?=-31.25kJ·mol-1, respectively. The IR spectra of the loaded organic phase supported the suggested extraction mechanism.  相似文献   

2.
The crystal structure of the title complex, [Cu(C23H26N2)Cl2]2·2CH2Cl2, has been determined by single-crystal, X-ray diffraction techniques. The compound crystallizes as dark-green prisms in space group P21/c of the monoclinic system, with Z=4 and unit cell dimensions a=1.710 9(7) nm, b=2.395 2(11) nm, c=1.348 9(6) nm and β=110.651(8)°. The complex consists of two similar but crystallographically independent dimers, of which Cu(Ⅱ) centers display five-coordinated trigonal-bipyramidal geometry with Cu-Cu separations in two centrosymmetric dimers are 0.345 1 and 0.347 8 nm, respectively, and in each dimer the two copper centers share a common edge formed by two bridging chloride ions, each being equatorial. Solvent molecules of CH2Cl2 are packed together in the crystal lattice. CCDC: 253299.  相似文献   

3.
The extraction of uranyl nitrate was studied with newly synthesized unsymmetrical alkylamides, Nmethyl-N-octyloctylamide (MOOA), N-methyl-N-octyldecanamide (MODA), and N-methyl-N-octyldodecanamide (MODOA), employing n-octane as diluent. The effect of the concentrations of nitric acid, sodium nitrate and extractants on the extraction was investigated and the extraction mechanism was suggested. The effect of temperature on the extraction was also studied and the related thermodynamic functions were calculated. The extracted species were characterized by FTIR spectrometry。  相似文献   

4.
The solvent extraction of U(Ⅵ) from nitric acid solution was studied with one new extractant, 4-p-methylbenzoyl-2,4-dihydron-5-methyl-2-phenyl-pyrazol-3-thione (HMeBMPPT), synthesized via acylation, chlorination and sulfurication of the starting material 1-phenyl-3-methyl-pyrazolone-5(PMP) in high yield. The structure of the new extractant was confirmed by means of elemental analysis, MS, 1H NMR and X-ray diffraction. The effects of diluent, temperature, the concentrations of nitric acid, and the concentration of extractant on the extraction were investigated and the extraction mechanism is suggested.  相似文献   

5.
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   

6.
The extraction behavior of N,N′-diethyl-N,N′-dibenzenyl-urea (DEDBU) to Uranium(Ⅵ) and Thorium(Ⅳ) from nitric acid solution was studied by using xylene as diluent. The effects of aqueous HNO3 concentration and ex-tractant concentration on the extraction distribution ratio of U(Ⅵ) and Th(Ⅳ) were studied, and the results show that the extraction behavior of the extractant to U(Ⅵ) is similar to tributyl phosphate (TBP), the solvation numbers for DEDBU and TBP are two, respectively. Under the experiment condition, the extractant does not show the extraction behavior to Th(Ⅳ), this result exhibits that the extractant has good application to separate U(Ⅵ) and Th(Ⅳ). The crystal structure of the complex UO2(NO3)2[CH2(CH2)2CONC8H17]2 was determined by single crystal X-ray diffraction. Crystal data: C24H46N4O10U, triclinic, space group , a = 8.662(2)?, b= 10.07(2)?, c= 10.895(3)?, α = 103.77(2)°, β = 92.01(2)°, γ = 96.23(2)°, V= 915.7(4)?3, Mr = 934.78, Z= 1, Dc= 1.695 g·cm-3, F(000) = 462, μ = 4.495mm-1, R= 0.0250, wR= 0.0591, observed reflec-tions 3566 (I>2σ(I)).The central uranyl ions is coordinated by six oxygen atoms, two of them are from the carbonyl groups of N,N′-diethyl-N,N′-dibenzenyl-urea molecules, and the other four are from two nitrate groups.  相似文献   

7.
L-苏糖酸锰的制备及标准生成焓   总被引:1,自引:0,他引:1  
The pink powder of manganese L-threonate was obtained by extracting with alcohol the concentrated solution derived from the reaction between L-threonic acid solution prepared by double decomposition reaction of calcium L-threonate with oxalic acid and superfluous manganese oxide at 80℃ for certain time. The composition of the new compound was determined by chemical and elemental analyses and its formula fits Mn(C4H7O5)2·H2O, the IR spectra indicated that Mn2+ in the compound coordinates to oxygen atom of the carboxyl group, while the proton of the carboxyl group is dissociated, it was assumed that the coordination number of Mn2+ was 4. The results of TG-DTG showed that the compound have fairish stability, the intermediate and final product of the thermal de-composition of the compound are Mn(C4H7O5)2 and MnO2, respectively. The constant volume combustion energy of the compound, ΔcE, were determined by a precise rotating-bomb calorimeter at 298.15K, it was (-3384.30±1.21)kJ·mol-1, its standard enthalpy of Combustion,ΔcHm?,and standard enthalpy of formation,ΔfHm? , were calculated. They are (-3383.07±1.21)kJ·mol-1 and (-2 571.68±1.63)kJ·mol-1, respectively.  相似文献   

8.
合成大比表面γ-Mo2N的新方法   总被引:16,自引:0,他引:16  
The production of high specific surface area γ-Mo2N (up to 165 m2·g-1, passivated) by temperature programmed reaction of MoO3 with mixtures of N2 and H2 was reported. The synthetic condition of high surface area γ-Mo2N (usually, SBET>100 m2·g-1) were quite difficult and the amount of starting material MoO3 in each batch was much less than 0.5 gram. However, some synthetic conditions had been greatly improved in our experiments. The crystalline phase and specific surface area had been characterized by XRD and BET. The XRD gave some information for reaction mechanism.  相似文献   

9.
郝仕油 《无机化学学报》2007,23(8):1477-1480
Nanometer Ce1-xLaxO2-δ solid solutions were synthesized by microwave-induced combustion process us-ing cerium nitrate hexahydrate, lanthanum nitrate hexahydrate and urea as raw materials. The process took only six minutes to obtain La2O3-doped CeO2 nanopowders. The nanopowders were characterized by XRD, Laser Raman spectrum , UV-Vis spectroscopy,field-emission scanning electron micrograph(FE-SEM)and TEM. The results revealed that the grain size of Ce1-xLaxO2-δ varied from 20 to 40 nm calculated by Scherer formula through the plane of (111), that oxygen vacancy was produced in the crystal lattices and the concentration of oxygen vacancy was increased with La doping, therefore the covalence of Ce-O bond was strenthened, which results in more intensive UV-C(200~280 nm)absorption. It can be seen from SEM that the porous appearance was obtained. Grain size is no more than 40nm observed from TEM.  相似文献   

10.
Treatment of deprotonated N,N′-bis(4-methyl-2-benzothiazolyl)-2, 6-pyridicarboxamide (L2-) with CoCl2·6H2O yields the mononuclear complex, (Et4N)2[CoL2]·0.5H2O. Single crystal X-ray structural determination has been carried out for the complex, crystal system: Monoclinic, space group: P21/c, a=1.444(1) nm, b=1.969(1) nm, c=2.448(1) nm, β=118.02(1)°, V=6.143 0(15) nm3, Z=4. In this complex, the central Co(Ⅱ) atom is in an octahedron environment, with four deprotonated amide-N atoms in the equatorial plane and two pyridine-N atoms in the axial positions. CCDC: 252558.  相似文献   

11.
CexPr1-xO2-δ复合氧化物的XRD和Raman表征   总被引:1,自引:0,他引:1  
A series of CexPr1-xO2-δ mixed oxides were synthesized by sol-gel method and characterized by Raman and XRD techniques. When x value was changed from 1.0 to 0.5, only a cubic phase CeO2 was observed. The samples were very well crystallized on decreasing x from 0.50 to 0.99. For CexPr1-xO2-δ samples 465 cm-1 and 1 150 cm-1 Raman peaks are attributed to the Raman active F2g mode of CeO2. The broad peak at about 570 cm-1 in the region of 0.3 ≤x≤ 0.99 can be linked to lattice defects resulting in oxygen vacancies. The new band at about 195 cm-1 may be attributed to the asymmetric vibration caused by the formation of oxygen vacancies. Calcination temperatures had great effect on the peak intensity for CeO2 but less effect on Ce0.8Pr0.2O2-δ in Raman spectra. It might be due to the transformation of the colors for the mixed oxides, the insertion of Pr atom into the ceria lattice could enhance the sintering resistance and thermal stability of the mixed oxides.  相似文献   

12.
The reaction of 3-ethoxysalicylaldehyde-N,N-bis(3-aminopropyl)methylamine with Zn(Ⅱ) acetate in CH3CH2OH followed by recrystallization in CH3CH2OH gave rise to colourless block crystals of 3-ethoxysali-cylaldehyde-N,N-bis(3-aminopropyl)methylamine Zn(Ⅱ). The compound has been characterized by elemental analysis, IR spectrum, molar conductivity and X-ray diffraction structure determination single crystal. It crystallizes in monoclinic, space group P21/c with a=1.028 91(13) nm, b=1.400 35(12) nm, c=1.733 69(19) nm, V=2.476 6(5) nm3, Z=4, Mr=504.91, Dc=1.354 g·cm-3, T=298(2) K, F(000)=1 064, μ(Mo Kα)=0.102 7 cm-1, R=0.068 4 and wR=0.185 3 for 2 940 observed reflections with I>2σ(I). The fluorescence properties of ligand and the complex also have been investigated. The results show that the fluorescence intensity of the Zn(Ⅱ) complex is very stronger than the ligand. In the crystal, the molecules form 1D chain structure by π-π stacking. CCDC: 675010.  相似文献   

13.
The Cluster compound [Cu3BrWOS3(bipy)2] was synthesized by reaction of (NH4)2WOS3, CuBr, 2,2′- bipyridine and n-Bu4NBr at room temperature and characterized by IR, UV and elemental analyses. The structure of [Cu3BrWOS3(bipy)2] was determined by single crystal X-ray diffraction revealing that the cluster consist of a nest -shaped core. The W atom is tetrahedrally coordinated by three S atoms and one O atom. There are two types of copper atoms in the WOS3Cu3 aggregate: two copper atoms are tetrahedrally coordinated and another copper atom is trigonally coordinated. The nonlinear optical properties were studied with an 8ns pulsed laser at 532nm. Its optical responses to the incident light exhibit considerably optical absorptive and strong self-focusing effect with α2=0.90×10-10m·W-1n2=2.72×10-18m2·W-1. CCDC: 196348.  相似文献   

14.
稀土与β-二酮及2-(2-吡啶)苯并咪唑三元配合物的研究   总被引:2,自引:0,他引:2  
As useful fluorescent reagent, rare earth complexes with β-diketones have been extensively studied. Four new rare earth (La, Eu) ternary complexes with β-diketones, (benzoylacetone (Hbza), 2-thenoyltrifluoroacetone, (HTTA)) and organic base (2-(2-pyridyl) benzimidazole, (Hpbi)) have been synthesized and characterized by elemental analysis, IR, NMR. The general formulae of these complexes are [Ln(bza)3(Hpbi)] and[Ln(TTA)3(Hpbi)]. The effects of coordinated base on UV, especially on fluorescent properties of the complexes were discussed. The results showed that the dehydro-Hpbi, pbi-, strongly enhances the fluorescence of the complexes.  相似文献   

15.
A novel N,N′-dibenzyl-benzimidazolium tetrachlorocuprate(Ⅱ) complex, [C21H19N2]2[CuCl4], was synthesized and its crystal structure was determined by X-ray diffraction. It crystallizes in monoclinic system, space group P2/c, a=1.203 9(2) nm, b=0.975 0(2) nm, c=1.878 2(6) nm, β=114.12(2)°, V=2.012 2(8) nm3. Its structure was identified by EA, IR and UV spectra and characterized by electrochemistry, thermal and magnetic property. The Cu(Ⅱ) atom of [CuCl4]2- has distorted tetrahedral coordination geometry. In the crystal structure, there are strong extensive C-H…Cl hydrogen bonds and π-π stacking interactions, which stabilized the crystal structure. CCDC: 221570.  相似文献   

16.
Precursor molecule (R)-6,6′-bis(triethoxysilylethen-2-yl)-2,2′-di(methoxyethoxymethyloxy)-1,1′-binaphthyl (R-2) was synthesized by Pd-catalyzed Heck reaction of (R)-6,6′-dibromo-2,2′-di(methoxyethoxymethyloxy)-1,1′-binaphthyl (R-1) intermediate with vinyltriethoxysilane. The hydrolysis and polycondensation of the precursor R-2 produced the corresponding xerogel. Both precursor and xerogel were analysed by NMR, FTIR, UV, CD spectra, fluorescent spectroscopy, polarimetry and elemental analysis. The precursor and xerogel can emit strong blue fluorescence and are expected to have a potential application in the separation of chiral molecules as fluorescent sensor. The precursor exhibits strong Cotton effect in its circular dichroism (CD) spectrum indicating a highly rigid structure.  相似文献   

17.
The structure and catalytic properties based on Chromium Oxide supported on mesoporous SBA-15 for oxidative dehydrogenation of propane by CO2 have been studied by using X-ray diffraction (XRD), ultraviolet-visible diffuse reflectance spectra (UV-Vis DRS), electron spin resonance (ESR), X-ray photoelectron spectroscopy (XPS) and propane pulsing experiments in the absence of gas-phase O2. It has been shown that propane conversion and propene yield increase with Cr loadings. The propane conversion and propene yield on CrOx(Cr: 10wt%)/SBA-15 catalyst for oxidative dehydrogenation of propane by CO2 at 550 ℃ reach 24.8% and 21.8%, respectively .The results of ESR, UV-Vis DRS and propane pulsing experiments indicate that Cr in the CrOx/ SBA-15 catalyst is the main active species in oxidative dehydrogenation of propane by CO2 and Cr, Cr is inactive in dehydrogenation.  相似文献   

18.
Six triphenyltin(Ⅳ)N-alkylpiperazinyldithiocarbamates have been synthesized by the reaction of triphenyltin chloride with N-alkylpiperazinyldithiocarbamates and characterized by elemental analysis, UV, IR and 1H NMR. The crystal structure of Ph3SnS2CN(C2H4)2NCH3(1) has been determined by X-ray single crystal diffraction. The crystal of the compound 1 belongs to triclinic with space group P1, a=1.033 56(18) nm, b=1.148 8(2) nm, c=1.191 6(2) nm, α=66.282(2)°, β=78.756(2)°, γ=67.476(2)°, Z=2, V=1.195 2(4) nm3, Dc=1.460 g·cm-3, μ=1.256 mm-1, R=0.025 1, wR=0.058 3. The structure shows a distorted tigonal bipyramidal configuration with five-coordination for the central tin atom. CCDC: 240375.  相似文献   

19.
LaMgAl11O19∶Eun+(n=2,3) was synthesized by solid state reaction using H3BO3 as a flux at 1 400 ℃ for 4 hours. And their luminescent properties was investigated under UV and VUV excitation. Strong pure blue emission due to d-f transition of Eu2+ was observed in LaMgAl11O19∶Eu2+ both in 254 nm and 147 nm excitation. At the same time, red emission due to 5D07FJ (J=0, 1, 2, 3, 4) transition of Eu3+ also observed in LaMgAl11O19∶Eu3+. The dependence of emission intensity of blue/red emission on Eu2+ / Eu3+-content was evaluated. The result indicated that the blue emission intensity was arrived optimum when Eu2+-content was 0.10 mol·mol-1under both UV and VUV excitation while red emission intensity reached optimum when Eu3+-content was 0.125 mol·mol-1 under UV excitation. This suggests that LaMgAl11O19∶Eu2+ phosphors could be potential blue phosphor for the application in PDP.  相似文献   

20.
温广  张朋 《无机化学学报》2005,21(10):1535-1540
Temperature-programmed reduction (H2-TPR) was employed to quantitatively characterize the active oxygen species generated from a high Fe-loading Fe/ZSM-5 catalyst exposed to N2O at 250 ℃. [Fe-O-Fe]2+ dimer was determined as the active iron complex for N2O decomposition to produce the active oxygen. Reduction of Fe3+ to Fe2+ by H2 in the dimer and removal of OH- groups from Fe2+ dimer by heating Fe/ZSM-5 to 700 ℃ were the prerequisites for the formation of this active Fe complex. A linear correlation with a slope of 1.0 between the amount of [Fe-O-Fe]2+ and that of active oxygen species was observed. Maximum amount of active oxygen species can be generated by reducing Fe/ZSM-5 catalyst with H2 at the temperatures over 500 ℃ and then heating the resulting product in Ar to 700 ℃, followed by N2O exposure at 250 ℃. The ratio of the total number of oxygen atoms (Ode) deposited by interaction of [Fe-O-Fe]2+ with N2O to the amount of [Fe-O-Fe]2+ was 2. However, not all the deposited oxygen atoms were active oxygen (Oa); the ratio of Oa and Ode was 0.5. The iron dimer complex composing active oxygen is a five-atom ion [Fe2O3]2+; the most probable structure is as follows:  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号