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1.
Tetragonal tungsten bronze K0.71Nd0.028WO3 was synthesized by rare earth co-permeation method using Keggin type POMs of α-K10[SiCu3(OH2)W9O37]·6H2O (abbreviated as SiW9Cu3) as precursor. XRD, XPS, XRF, TG-DTA were used to characterize the resulting material. The XPS results indicate that Nd has permeated and diffused into the body of the sample and exists in tungsten bronze in the form of K0.71Nd0.028WO3. The results of TG-DTA show that K0.71Nd0.028WO3 begins to decompose at 320 ℃. The consequence of DC four-probe shows that the conductivity of the sample permeated by rare earth is 103 times higher than that of the sample only permeated by methanol at room temperature. The conductivity of the sample only permeated by methanol is only 10-3 S·cm-1 but the conductivity of the sample permeated by rare earth is 1.65 S·cm-1.  相似文献   

2.
Mo的掺杂对Ce0.8Gd0.2O1.9烧结温度及电性能的影响   总被引:1,自引:1,他引:0  
Ce0.8Gd0.2O1.9 ceramics were synthesized by sol-gel method and the effect of MoO3 addition on the sintering temperature, microstructure and electrical properties was examined. The structures and ionic conductivities were characterized by TG/DTA, XRD, field-emission scanning electron microscopy (FE-SEM) and electrochemical impedance spectroscopy (EIS). The results showed that Mo-doped ceramics exhibited viscous flow, which reduces friction of the particles, promots mass diffusivity of the matrix grain boundary mobility, and thus enhances further densification during subsequent sintering. The conductivities of grain boundary and grain interior increased with the decreasing of the grain boundary resistance. With Mo-dopant, the grain interior conductivity increased from 1.27×10-3 S·cm-1 to 5.46×10-3 S·cm-1, and the grain boundary conductivity increased from 1.02×10-3 S·cm-1 to 2.89×10-3 S·cm-1 at 600 ℃ for Ce0.8Gd0.2O1.9.  相似文献   

3.
A dense La0.8Sr0.2Ga0.83Mg0.17O2.815 electrolyte in pure perovskite phase was prepared by a polyacrylic acid assisted solid state reaction method, and the effects of La source on the structure and electrochemical performance were also studied. By means of XRD and SEM, the structure of this material was characterized, and the electrochemical properties were studied through AC impedance diagram. The results show that the sample presents a single perovskite-type phase after sintering at 1 450 ℃ and the relative density is 94%. The specimen has the lower activate energy and higher electrical conductivity at 600 ℃. There are two different activation energy at the turning point of 650 ℃, which are 74.6 and 42.4 kJ·mol-1, respectively. The electrical conductivity is 0.057 S·cm-1 and 0.017 S·cm-1 at the temperature of 800 ℃ and 600 ℃, respectively.  相似文献   

4.
Eight new complexes were synthesized for the first time. The compounds which have the general formula KxH2[PM(OH2)Mo7W2V2O39nH2O(M=Cr3+,Mn2+,Fe3+,Co3+,Ni2+,Cu2+,Zn2+, Cd2+; x=4 or 5) were de-termined by conductance titration and elemental analysis. The analysis of IR, UV, XRD and ESR show that the products hold the Keggin structure and TG-DTA, IR, XRD at various temperatures and water solubility test also give the evidences that the range of pyrolysis temperature is 300~350℃. The study on the substitutional reaction of coordinated water by optical ligand quinine shows that the SN2 nucleophilic substitution occures when Ni is con-tained in the compound and SN1 nucleophilic substitution occures when Cu is contained. These also confirmed that the transitional metals are in the inner sphere of the complexes.  相似文献   

5.
The new title complexes [M(mnt)(phen-5,6-dione)](M=Ni(Ⅱ)、 Cu(Ⅱ)、 Zn(Ⅱ), mnt=maleonitriledithiolate) are synthesized by reaction of Na2(mnt) with relevant [M(phen-5,6-dione)Cl2], respectively. The structure and properties of the complexes were characterized by elemental analysis, molar conductivities, TG,IR, UV-Vis, and fluorescence spectra.  相似文献   

6.
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   

7.
The reactions of the tetranuclear hydroxo complexes [M42-OH)8(H2O)16]8+ (M = Zr or Hf) with the lacunary Keggin-type ([α-PW11O39]7−) and Dawson-type ([α 2-P2W17O61]10−) phosphotungstates in aqueous solutions produce the sandwich polyoxometalate complexes [M(α-PW11O39)2]10− (M = Zr (1) or Hf (2)) and [M(α 2-P2W17O61)2]16− (M = Zr (3) and Hf (4)). The complexes were isolated and structurally characterized as salts with potassium and dimethylammonium cations. The zirconium and hafnium atoms have a square antiprismatic coordination environment (coordination number is 8). In all complexes, the mutual arrangement of the ligands corresponds to the syn isomer. Hafnium complexes 2 and 4 are the first structurally characterized polyoxometalate complexes of this metal. The structures of the resulting compounds were confirmed also by 31P NMR spectroscopy in solution. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 214–218, February, 2007.  相似文献   

8.
一种有机-无机电荷转移配合物的合成、结构及性能研究   总被引:1,自引:0,他引:1  
A charge-transfer complex, [(C2H4OH)3NH]2·[HPMo12O40]·3H2O, has been synthesized and characterized.The crystal structure of the complex was determined by X-ray diffraction. It belongs to orthorhombic, space grounp Pnna, with a=1.541 30(5) nm, b=1.884 23 (7) nm, c=2.049 06(7) nm, α=β=γ=90.00°, V=5.950 8(4) nm3, Z=4, Dc=2.427 Mg·m-3 , F(000)=4 132, μ(Mo )=2.568 mm-1. The structure was refined to R1=0.043 5 and wR2=0.122 4 by full-matrix least-squares method. The O atoms of the polyoxometalate, the C atoms of the organic substrates and the O atoms of water molecules are involved in hydrogen bonding. Spectral data support the presence of an electronic interaction between the organic substrate and the inorganic anion in the solid state. It is strongly photochromic under ultraviolet light resulting from charge-transfer. The electrochemical behavior of the compound shows that the redox peak currents are proportional to the scan rate in pH=4.0 NaAc-HAc buffer solution, which indicates that the electrode reaction are surface controlled processes.  相似文献   

9.
Two new heteropolynuclear metal complexes [Ni(phen)23[Cr(ox)32·8H2O(1) and [Ni(bipy)22[Cr(ox)3]NO3·4H2O(2)(phen=1,10-phenanthroline, ox=oxalato, bipy=2,2-bipyridine) have been synthesized and characterized by elemental analyses, IR, TG-DTA and diffuse reflectance UV-VIS spectra. The temperature dependence of the magnetic susceptibilities of the complexes have been studied over the range 73.6~300K. The results show that ferromagnetic spin exchange interaction exist between Cr(Ⅲ) and Ni(Ⅱ) in the complex (1). The magnetic property of the complex(2) abides Curie law.  相似文献   

10.
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   

11.
对GB 11892 - 1989《水质 高锰酸盐指数的测定》中酸性高锰酸钾氧化法测定水中高锰酸盐指数的测量不确定度进行了评定。通过对测量重复性、滴定管、移液管、标准溶液浓度等影响测量结果的不确定度分量的分析和量化 ,求得水中高锰酸盐指数测定结果的相对合成标准不确定度为 1.10× 10 -2 。  相似文献   

12.
对生物探针与脱氧核糖核酸(DNA)的结合模式及有机染料分光光度法测定DNA的研究进展进行了综述。引用文献71篇。  相似文献   

13.
生活饮用水总硬度测量结果的不确定度评定   总被引:1,自引:0,他引:1  
对乙二胺四乙酸二钠滴定法测定生活饮用水总硬度的测量不确定度进行评定。分析了测量重复性、标准溶液的浓度、滴定管、取样等因素对总硬度测量不确定度的影响,求得生活饮用水总硬度测定结果的相对合成标准不确定度为2.74×10-3。  相似文献   

14.
本文采用家兔肺泡巨噬细胞(AM)体外培养法,以细胞内游离钙浓度([Ca~(2+)]_i)、细胞存活率、乳酸脱氢酶(LDH)和酸性磷酸酶(ACP)活性为指标,观察了卵磷脂、脑磷脂及现用防治硅肺药物克矽平(PVPNO)、柠檬酸铝等抗石英毒效果。结果表明:卵磷脂在所试各药物中效果最佳.初步探讨了卵磷脂拮抗石英细胞毒性的机理.卵磷脂有成为防治硅肺药物的可能性.  相似文献   

15.
热塑性塑料熔体质量流动速率测量不确定度的评定   总被引:1,自引:0,他引:1  
以聚乙烯为例讨论了热塑性塑料熔体质量流动速率测量不确定度的来源,依据JJF 1059-1999对熔体流动速率测试过程中的测量不确定度分量进行了分析和评定。7149型聚乙烯熔体质量流动速率测量结果的扩展不确定度为0.096 g/(10 m in)。  相似文献   

16.
对铕测定方法的近期进展作了评述,涉及的测定方法有荧光光度法、吸光光度法、原子发射光谱法、原子吸收光谱法、X-射线荧光光谱法、质谱法及伏安法等。还对该领域的研究动态作了简要讨论(引述文献59篇)。  相似文献   

17.
铽与吡啶-2,6-二羧酸(以下简称DPA)形成螯合物的萤光有人从生物化学角度作过一些研究[1],但对测定稀土氧化物中微量铽的研究未见报导。本文系统地研究了Tb3+-DPA螯合物萤光产生的条件,拟订了测定稀土氧化物中微量铽的萤光光度法,探讨了螯合物萤光强度与其组成的关系。  相似文献   

18.
Reaction of(Z)-Crotyldiisopinocampheylborane with a series of alde-hydes have been examined,and the ratio of erythro to threo products varies fr-om 20:1 to 1:1.The results are discussed in detail.  相似文献   

19.
<正> 高聚物的凝胶化理论已有不少报道,但对聚氨基甲酸酯系统需提出特定的模型.本文根据聚氨基甲酸酯形成过程中存在的各种反应,建立了新的凝胶化模型.经过统计处理,即假设中心官能团重现系数等于1作为凝胶化临界条件,导得了聚氨基甲酸酯体系的凝胶化数学关系式.其简化模型所得凝胶化条件与文献中导得结果完全相同.  相似文献   

20.
评述荧光光度法、放射化学法、气相色谱法、高效液相色谱法、电化学法等方法检测组织液及细胞中儿茶酚胺类物质的特点及进展。  相似文献   

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