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1.
New solid rubidium-conducting electrolytes based on rubidium monoferrite in the system of Rb2 − 2x Fe2−x V x O4 are synthesized and studied. It is found that introduction of V5+ ions causes a drastic decrease in the electronic conductivity component prevalent in pure RbFeO2 with a simultaneous increase in the ionic conductivity. The latter becomes predominant at an increase in the concentration of vanadium. The optimum compositions of the studied electrolytes feature a very high cationic rubidium conductivity (∼1.8 × 10−2 S cm−1 at 200°C, more than 10−1 S cm−1 at 700°C). The results are compared with the data obtained earlier for similar systems based on RbGaO2 and RbAlO2.  相似文献   

2.
Synthesis and ionic conductivity of Li3−2x Nb x Fe2−x (PO4)3 complex phosphates were studied by X-ray powder diffraction and impedance spectroscopy. These phosphates are formed only at 900–1000°C. Variations in their thermal expansivity and unit cell parameters induced by aliovalent doping were characterized. The conductivity of these materials increases monotonically in the series Li0.5Nb1.25Fe0.75(PO4)3-LiNbFe(PO4)3 and Li1.2Nb0.9Fe1.1(PO4)3-Li3Fe2(PO4)3, which is explained by consecutive occupation of the Li(1) and Li(2) positions in their structures. Original Russian Text ? A.R. Shaikhlislamova, I.A. Stenina, A.B. Yaroslavtsev, 2008, published in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 12, pp. 1957–1962.  相似文献   

3.
Li1 − x Ti2 − x Nb x (PO4)3 NASICON materials are prepared and studied by X-ray diffraction, 7Li and 31P NMR spectroscopy, and impedance spectroscopy. Vacancy mobility in Li1 − x Ti2 − x Nb x (PO4)3 is lower than interstitial lithium mobility. Nb5+ cations with low doping levels increase cation mobility in LiTi2(PO4)3. Original Russian Text ? I.Yu. Pinus, I.A. Stenina, A.I. Rebrov, N.A. Zhuravlev, A.B. Yaroslavtsev, 2009, published in Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54, No. 8, pp. 1240–1244.  相似文献   

4.
A multicomponent system of complex refractory oxides of the composition Zn2 − x (Zr a Sn b )1 − x Fe2x O4 (a + b = 1; a: b = 1: 5, 1: 4, 1: 3, 1: 2, 1: 1, 2: 1, 3: 1, 4: 1; x = 0−1.0; Δx = 0.05) was studied by X-ray diffraction. The samples were prepared from oxides of appropriate metals by low-temperature plasma synthesis (hydrogen-oxygen flame). Two phases with wide homogeneity ranges were identified: α phase crystallized in the crystal system of inverse cubic spinel and β phase with the structure of tetragonal spinel. The phase boundaries were found. Structural data are presented for about 100 solid solutions.  相似文献   

5.
Li1 +x Ti2 − x Ga x (PO4)3(x= 0−0.2) NASICON double phosphates are prepared and studied by high-temperature X-ray diffraction, 7Li NMR spectroscopy, impedance spectroscopy, and calorimetry. Doping with Ga3+ cations increases cation mobility in LiTi2(PO4)3. Ion conductivity, NMR spectroscopy, and calorimetry data imply the occurrence of a phase transition in LiTi2(PO4)3 and in products of partial gallium-for-titanium substitution. Original Russian Text ? I.Yu. Pinus, I.V. Arkhangel’skii, N.A. Zhuravlev, A.B. Yaroslavtsev, 2009, published in Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54, No. 8, pp. 1235–1239.  相似文献   

6.
The phase compositions of theLaVO4-SrMoO4(1) and Sr2GeO4-SrMoO4 (2) binary systems, which bound the Sr2GeO4-LaVO4-SrMoO4 (3) ternary system, and the LaSr2(VO4)(GeO4)-Sr2GeO4+SrMoO4 section (4) of system 3 are studied at subsolidus temperatures. Systems 1 and 2 consist of a mixture of the initial compounds, and the La1 − x Sr2 + x (GeO4)(V1 − x Mo x O4) (where 0 ≤ x ≤ 0.4) region of substitutional solid solutions with a palmierite structure is formed in system 3. The unit cell parameters of the solid solutions are determined. The distribution of the lanthanum and strontium cations over two positions of the cationic sublattice is described. Original Russian Text ? V.D. Zhuravlev, V.G. Zubkov, A.P. Tyutyunnik, Yu.A. Velikodnyi, N.D. Koryakin, 2009, published in Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54, No. 1, pp. 135–137.  相似文献   

7.
The crystals of [Co6H2O][Co4H2O2Gly]2SO4 were studied by X-ray diffraction analysis (triclinic, P , a = 5.975(5), b = 15.469(5), c = 6.765(5) , =120.71(5), =83.23(5), =98.77(5)°). The structure contains complex cations of two types: [Co6H2O]2+ and [Co4H2O2Gly]2+ and SO 4 2– anions linked by hydrogen bonds and electrostatic forces. Three chemically nonequivalent charged layers can be distinguished in the structure: one layer is formed by cobalt hexaaqua complexes, another by [Co4H2O2Gly]2– complexes, and the third layer consists of sulfate anions interlaying the former two. The layers alternate along the b axis and are connected by a 3D system of hydrogen bonds.  相似文献   

8.
NOx存储-还原技术是控制汽车稀燃NOx排放的重要手段之一,在汽车尾气中H2O、CO2组分含量均相对较高,有必要弄清这些组分对NOx存储-还原特性的影响。论文以MnOx改性Pt/Ba/Al2O3催化剂为研究对象,评价在不同气氛下的NOx存储能力和催化还原性能。结果表明:CO2、H2O组分均抑制催化剂的NOx存储性能,H2O的抑制作用主要表现在低温区,CO2抑制NOx存储的现象在高温区更为显著。CO2对NOx存储速率的抑制作用较H2O更为明显,且其NOx存储速率随着温度的升高表现的差异性更为明显。对于NOx催化还原过程,CO2、H2O或CO2 H2O添加均导致N2选择性降低,其N2选择性按CO2 > H2O > CO2 H2O的顺序降低。  相似文献   

9.
A novel bimetallic 4f-3d metal-isonicotinic acid inorganic-organic hybrid complex [Tb0.5(C6NO2H5)3(H2O)2]2n ·(H3O)4n (ZnCl5) n (ZnCl4)2n (1) is synthesized. It has a one-dimensional polycationic chain-like structure. Photoluminescent investigation reveals that it displays interesting emissions in the violet, blue, green, and yellow regions.  相似文献   

10.
A novel cobalt(Ⅱ) complex with biphenyl-3,3′,4,4′-tetracarboxylic acid (H4bptc) and 2-phenyl-1,3,7,8-tetraazacyclopenta[l]-phenanthrene (ptcp), {[Co(H2bptc)(ptcp)(H2O)2]·H2O}n(1), has been synthesized by hydro-thermal method and was characterized by elemental analysis, single crystal X-ray diffraction and thermal gravimetry (TG). It crystallizes in monoclinic, space group Pn with a=0.719 44(14) nm, b=1.259 4(3) nm, c=1.681 9(3) nm, β=93.30(3)°, V=1.521 5(5) nm3, Z=2, C35H26CoN4O11, Mr=737.53, Dc=1.610 g·cm-3, μ(Mo Kα)=0.639 mm-1, F(000)=758, S=1.024, R1=0.076 7 and wR2=0.120 6. The structural analyses reveal that the title complex is a 1D zigzag chain strcture along the c axis, which is stacked to furnish a three-dimensional supramolecular net structure via hydrogen bonding interactions. CCDC: 793796.  相似文献   

11.
Quantitative online NMR spectroscopy was used for studying the species distribution in solutions of carbon dioxide in aqueous monoethanolamine (MEA) and diethanolamine (DEA). The mass fraction of the amine in the unloaded solution was 0.2 and 0.3 g/g, respectively, the carbon dioxide loading was up to 1.1 ??molCO2/molamine1.1 ??molCO2/molamine, temperatures were between 293 and 353 K. A special apparatus was designed that allows preparing the mixtures gravimetrically and applying pressures up to 25 bar to keep the carbon dioxide in solution. It was coupled to a 400 MHz NMR spectrometer by heated capillaries. By using both 1H and 13C NMR spectroscopy quantitative information on the concentrations of the following species were obtained: amine, carbamate, bicarbonate, and carbon dioxide. Due to the fast proton transfer between molecular and protonated amine, only the sum of their concentrations can be determined. Furthermore, a byproduct, 2-oxazolidone, was observed and quantified. The experimental data were used for developing a thermodynamic model of the studied electrolyte solutions based on the extended Pitzer GE-model. In the model development, also vapor–liquid equilibrium data from the literature were included. The model gives reliable results both for the species distribution and the vapor–liquid equilibrium of the studied mixtures.  相似文献   

12.
A novel coordination ploymer [{Zn(3-SBA)(2,2′-bipy)(H2O)2}·H2O]n was synthesized by the hydrothermal reaction of 3-Na2SBA, ZnSO4·7H2O and 2,2′-bipy. The structure was characterized by elemental analysis, IR and single crystal X-ray diffraction. The title coordination ploymer crystallized in monoclinic with space group P21, a=0.803 42(18) nm, b=1.501 8(3) nm, c=0.821 13(19) nm, β=109.350(4)°. The coordination polymer has an infinite chain structure and its luminescent property has also been studied. CCDC: 282746.  相似文献   

13.
为研究配位聚合物{[Cu(H2bttc)(H2O)3]·3H2O}n(H2bttc=1,2,4,5-benzenetetracarboxylate)的热分解机理和非等温反应动力学进行了DSC和TG-DTG热分析。由热分析结果和FTIR光谱推测了其热分解机理;将Kissinger法、Ozawa法、积分法和微分法得到的动力学参数进行比较确定了第一个失重过程最可能的动力学模型函数。配位聚合物的X射线单晶结构分析表明它由 [Cu(H2bttc)(H2O)3]n分子链组成,并有客体水分子通过分子间氢键附着在分子链上。这一结构特点与热分析结果相一致。还有一种氢键将分子链连接起来形成二维框架,这一框架在失去配位水和结晶水后到553 K开始分解。  相似文献   

14.
The title complexes, K[SmIII(Edta)(H2O)3] · 2H2O(I)(H4Edta = ethylenediamine-N,N,N′,N′-tetraacetic acid) and K2[SmIII(Pdta)(H2O)2]2 · 4.5H2O (II) (H4Pdta = propylenediamine-N,N,N′,N′-tetraacetic acid), were prepared and their compositions and structures were determined by elemental analyses and single-crystal X-ray diffraction techniques, respectively. Complex I has a mononuclear structure, and the Sm3+ ion is nine-coordinated by an Edta ligand and three water molecules, yielding a pseudo-monocapped square antiprismatic conformation, and the complex crystallizes in the orthorhombic crystal system with space group Fdd2. The crystal data are as follows: a = 19.84(5), b = 35.58(9), c = 12.15(3) ?, V = 8580(38) ?3, Z = 16, ρ c = 1.925 g/cm3, μ = 3.010 mm−1, F(000) = 4976, R = 0.0252, and wR = 0.0560 for 3510 observed reflections with I ≥ 2σ(I). Complex II has a binuclear structure and the Sm3+ ion is ten-coordinated by a Pdta ligand, two oxygen atoms from a carboxylic group of adjacent Pdta ligand and two water molecules, yielding a distorted bicapped square antiprismatic prism. The complex crystallizes in the triclinic crystal system with space group P $ \bar 1 $ \bar 1 . The crystal data are as follows: a = 8.9523(15), b = 10.7106(15), c = 11.6900(19) ?, α = 80.613(5)°, β = 80.397(5)°, γ = 76.530(4)°, V = 1065.7(3) ?3, Z = 1, ρc = 1.970 g/cm3, μ = 2.532 mm−1, F(000) = 1620, R = 0.0332 and wR = 0.0924 for 5390 observed reflections with I ≥ 2σ(I).  相似文献   

15.
Al synthesized samples are isostructural and crystallize in the orthorhombic symmetry system, space group Ibca. Particles of the final product of ∼200 nm in size have been obtained. The introduction of the vanadate anion into the matrix composition leads to the lowering of the symmetry of the Eu3+ environment and to the rise of the defect luminescence at 450–550 nm because of the unit cell distortion. The luminescence of defects in terbium-europium-containing samples is determined by the sample surface area, which decreases on annealing. The τ, W 0 and γ parameters of the luminescence kinetics of the samples have been determined.  相似文献   

16.
The hydrothermal reaction of VOSO4, As2O3, CoC2O4·2H2O and 2,2-bipy yields a novel arsenic-vanadate [CoII(2,2-bpy)2]2[AsIII8VIV 14O42(H2O)]·H2O (1), which is characterized by IR, elemental analysis, TGA, magnetic susceptibility and single crystal X-ray diffraction analysis. X-ray diffraction shows that compound 1 is the first example of tubular arsenic–vanadium cluster containing infinite {[Co(2,2-bpy)2]2[As8V14O42(H2O)]} chain constructed from [As8V14O42(H2O)] clusters interconnected through [Co(2,2-bpy)]2+ units. Crystal data: 1, orthorhombic, P 212121, a=12.1401(2) Å, b=15.8722(1) Å, c=39.9533(5) Å, Z=4.Graphical Abstract: A novel polyoxoarsenicvanadate, [CoII(2,2-bipy)2]2 [AsIII8VIV 14O42(H2O)]·H2O, is depicted along with a tubular hybrid solid with a rhombic tube formed within the chain.  相似文献   

17.
The title complex [Cu3(TFSSB)2·(H2O)4·4H2O]n (TFSSB=taurine 3-formylsalicylic schiff base) was synthesized by TFSSB and copper(Ⅱ) acetate monohydrate in ethanol solution and the crystal structure was determined by X-ray diffraction method. The crystal belongs to monoclinic system, space group P21 / n,with cell parameters: a=0.927 9(6) nm, b=1.173 0(2) nm, c=1.471(2) nm, β=106.96(2)°, and V=1.531(2) nm3, Z=2, Dc=1.890 g·cm-3, μ=2.291 mm-1, F(000)=882, R1=0.025 9, wR2=0.065 9. The Cu1 is five-coordinate, the Cu2 is four-coordinate. CCDC: 253298.  相似文献   

18.
A series of Cs2Te0.2H0.6 + x PMo12 − x V x O n (x = 0–3) heteropoly compounds has been prepared and tested in the partial oxidation of isobutane. Catalytic tests show that at 350°C very high selectivity to methacrylic acid (60.1%) can be achieved at isobutane conversion of 12.2% over a Cs2.0Te0.2H1.6PMo11VO n catalyst with only one molybdenum atom per unit cell substituted by vanadium. The presence of Te4+ in the heteropoly compounds appears to interfere with the dehydrqgenation step and favor the formation of methacrolein and methacrylic acid.  相似文献   

19.
C om m ent Silver and zinc salts of sulfadiazine are widely used to prevent bacterial infection for both hum ans and anim als during burn treatm ents[1~4]. Because the slow release of the m etal ions highly relevant to the biologicalactivity ofthese polym…  相似文献   

20.
The enthalpies of reactions of Sm1 + x Ba2 − x Cu3O y substitution solid solutions (x = 0, 0.1, 0.2, 0.3, 0.7, and 0.8) with 1.07 N HCl were measured at 298.15 K in a hermetic isothermic-shell swinging calorimeter. The results and the literature data were used to calculate the standard enthalpies of their formation from simple substances and binary oxides (Δf H 298.15o and Δox H 298.15o). The dependence of the enthalpy of formation on the degree of samarium substitution for barium was obtained.  相似文献   

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