高岭石结构缺陷的 1H MAS NMR和Raman研究

The structure default of kaolinites was characterized with ¹H MAS NMR and Raman spectra. Although the HI indexes of Suzhou and Maoming kaolinite are similar, their ¹H MAS NMR and Raman spectra are very different. ¹H MAS NMR showed that the hydroxyl proton chemical shifts of Suzhou kaolinite are in the higher field and with larger different between the inner surface hydroxyls protons and inner hydroxyls proton chemical shifts than Maoming kaolinite. Raman spectra showed that the surface hydroxyls stretching vibration bands of Suzhou kaolinite are in the high frequency region, and the half height widths of the bands are 7.0～14 cm^-1. The area ratio S_z/(S_z+S_A), where S_Z and S_A are the areas of bands 3685 cm^-1 and 3695 cm^-1 respectively, is 0.23. But the surface hydroxyls stretching vibration bands of Maoming kaolinite are in the low frequency region, and the half height widths of the bands are 8.9～15.1 cm^-1. The area ratio S_z/(S_z+S_A) is 0.77. Those data proved that Suzhou kaolinite has lower structure default than Maoming kaolinite and ¹H MAS NMR and Raman spectra are effective method for study of kaolinite structure default.     

一种确定固相反应机理函数的新方法——固态草酸镍(Ⅱ)二水合物脱水过程的非等温动力学

The dehydration of nickel(Ⅱ) oxalate dihydrate in solid state was investigated by TG-DTA techniques. On the basis of Coats-Redfern′s and Ozawa′s integral equations, the double extrapolate method was suggested, i.e.heating rate Φ and proportion weight loss of a sample α were extrapolated to zero, respectively. Using comparision E_Φ→0 with E_α→0 the kinetic mechanism was concluded to be nuclear producing and growing process (n=1.5). The intergral function of the mechanism is ［-ln(1-α)］^1/1.5 and the corresponding kinetic parameters were determined.     

类普鲁士蓝为前驱体制备纳米NiO及其电化学电容行为

Nanosized nickel oxide was synthesized by immersing the precursor NiHCNFe into 1 mol·L^-1 KOH solution to obtain nickel hydroxide (Ni(OH)₂) and then annealing in air at 300 ℃. X-ray diffraction (XRD) and transmission electron microscopy (TEM) tests showed the prepared samples were rhombohedral crystalline structure of NiO with uniform grain and with a diameter of about 8 nm. Electrochemical properties of NiO were examined by cyclic voltammetry, ac impedance and galvanostatic charge-discharge tests. The results demonstrated that nickel oxide had a good capacitive behavior and cyclability due to its nanostructure. The highest specific capacitance of nickel oxide was about 303 F·g^-1 at a charge/discharge current density of 5 mA·cm^-2 in 6 mol·L^-1 KOH solution.     

Eu3+在La2O2S中的长余辉发光

The new Eu³⁺ doped lanthanum oxysulfide phosphors,which have the orange-red long afterg low emission,were synthesized by solid-state reaction method.The synthesized phosphors were characterized by X-ray diffraction.The excitation and emission spectra,afterglow spectra and afterglow decay curves were examined.XRD confirmed the phosphor as pure phase La₂O₂S.The phosphors showed typical transitions ⁵D_J(J=0,1) → ⁷J_J(J=0,1,2,3,4)of Eu³⁺.The photoluminescence spectra and afterglow spectra presented the regular alteration with various Eu³⁺ concentration, due to cross relaxation between energy levels of Eu³⁺. In addition, we studied the effects of activator concentration and dopants species on the afterglow property. The data showed afterglow result was the best with 2 % Eu³⁺ and doped with Mg²⁺ and Zr⁴⁺. A prominent phosphorescence can be seen in this phosphor after illuminated with UV light.     

CexPr1-xO2-δ复合氧化物的XRD和Raman表征

A series of Ce_xPr_1-xO_2-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 Ce_xPr_1-xO_2-δ samples 465 cm^-1 and 1 150 cm^-1 Raman peaks are attributed to the Raman active F_2g 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 Ce_0.8Pr_0.2O_2-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.     

不同温度下VUV光激发的Pr3+离子的发光性质

The luminescent properties of Pr³⁺-doped LaB₃O₆, SrAl₁₂O₁₉, SrB₄O₇ and NaYF₄ in the vaccum ultraviol-et (VUV) range at different temperatures were investigated under the excitation of high-energetic synchrotron radiation. For Pr³⁺ ions in LaB₃O₆, SrAl₁₂O₁₉ and SrB₄O₇, only the parity-forbidden ¹S₀→4f² transitions were observ-ed in the emission spectra at relatively low temperature; but the parity-allowed 4f5d→4f² transitions appeared simultaneously when the temperature was high enough. And the intensity of broad 4f5d→4f² emission increased relative to the intensity of ¹S₀→4f² emissions with increasing temperature. Then the thermal equilibrium model of energy levels was employed to the lowest 4f5d state and ¹S₀ state of Pr³⁺ in the three hosts. The calculated curves were in good agreement with the experimental values, indicating the occurrence of the thermal excitation from ¹S₀ state to 4f5d states at high temperatures when the lowest 4f5d state lies higher than ¹S₀ state and the photon energy is high enough.     

Synthesis and characterization of poly(styrene/α-t-butoxy-ω-vinylbenzyl-polyglycidol) microspheres

Polystyrene microspheres with polyglycidol (polyGL) in a surface layer were synthesized in batch radical emulsifier-free emulsion copolymerizations of styrene and surfmers, α-t-butoxy-ω-vinylbenzyl-polyGL macromonomers (VB-polyGL). Macromonomers with number-average molecular weight Mˉ _n=950 (VB-polyGL950) and Mˉ _n=2700 (VB-polyGL2700) were used for these polymerizations. In all syntheses the initial concentrations of styrene and initiator (K₂S₂O₈) were constant. The initial macromonomer-to-styrene ratios were varied from 1.10 × 10⁻³ to 1.64 × 10⁻² mol/mol and from 3.46 × 10⁻⁴ to 3.47 × 10⁻³ mol/mol for VB-polyGL950 and VB-polyGL2700, respectively. The diameters of microspheres obtained were smaller for the syntheses with higher concentrations of macromonomers. Syntheses with VB-polyGL950 yielded microspheres with number-average diameters (Dˉ _n) from 216 to 900 nm and with a bimodal diameter distribution. The number-average diameters of microspheres obtained with VB-polyGL2700 varied from 220 to 650 nm, depending on the initial concentration of macromonomer. Their diameter distributions were monomodal, with a diameter polydispersity parameter (ratio of weight-average and number-average diameters) in the range 1.007≤Dˉ _w/Dˉ _n≤1.022. For each type of microsphere the fraction of polyGL in a surface layer and the surface concentration of sulfate anions were determined. The fraction of polyGL in the surface layer was related to the initial monomer composition in the polymerizing mixture. Adsorption of human serum albumin onto surfaces of some poly(styrene/VB-polyGL) microspheres was up to 10 times lower than for the polystyrene microspheres obtained in a similar emulsifier-free emulsion polymerization of styrene. Received: 26 September 2000/Accepted: 19 February 2001     

Spectrophotometric determination of nickel(II) in different samples by complexation with some triazolylazo dyes

A new sensitive spectrophotometric method for the determination of nickel(II) with 3-(2-hydroxy-5-acetyl-(L¹),-5-ethoxycarbonyl-(L²),-5-methyl-(L³),-5-formyl-(L⁴),-5-bromophen-1-ylazo)-1,2,4-triazole (L⁵), and 3-(2,4-dihydroxyphen-1-ylazo)-1,2,4-triazole (L⁶) in aqueous media containing 40 vol. % methanol has been developed. The method is based on the formation of stable coloured Ni(II) complexes with stoichiometric ratios 1: 1 and 1: 2 (n(M): n(L)). Linear calibration graphs are obtained up to 7.04 μg cm⁻³ of nickel(II) under optimum conditions attained from investigation of complex formation. The absorption maxima varied from 485 nm to 545 nm and the molar absorptivities ranged from 0.84 × 10⁴ to 4.65 × 10⁴ dm³ mol⁻¹ cm⁻¹ for 1: 1 and 1: 2 (n(M): n(L)) complexes with varying the substituent on the phenolic ring. The optimum ranges for the direct determination of nickel(II) (Ringbom) and the stability constants of the formed complexes are determined. The developed method was applied to the spectrophotometric determination of nickel(II) in some samples with satisfactory results.     

Pr3＋掺杂的LaF3纳米微晶/氟氧化物玻璃陶瓷的VUV光谱

The vacuum ultraviolet (VUV) spectroscopic properties of praseodymium (Pr^3＋, 1at%) doped LaF₃ nanocrystals/glass at room temperature and 20 K are reported. Two types of Pr^3＋ ions, those in LaF₃ nanocrystals and those in the glass host, were excited to 4f 5d band by VUV using synchrotron radiation as an excitation source, and emissions of ¹S₀ → ¹D₂ (336 nm), ¹S₀ → ¹I₆ (397 nm ) of Pr^3＋ in the nanocrystals and emissions of 4f 5d → ³H_J, ³F_J of Pr^3＋ in the glass appeared at the same time. But unlike in the bulk sample crystals, emission of ³P₀ → ³H_J, ³F_J as the second step of the quantum splitting (QS) of Pr^3＋ in the LaF₃ nanocrystals was not observed at room temperature, which could be explained that Pr^3＋ ions in the glass absorbed the energy of ³P₀→ ³H₄ of Pr^3＋ in the nanocrystals. Two types of excitation spectra monitoring different emissions were also measured, so it could be observed that the lowest energy of 4f 5d band of Pr^3＋ in the nanocrystals was about 53 500 cm^-1 (186 nm) and in the glass about 33 800 cm^-1(295 nm), respectively. These emission and excitation spectra were contrasted to those of bulk sample crystals LaF₃∶Pr^3＋.     

LiNi1-xMxVO4的红外光谱和拉曼光谱研究

The vanadates of LiNi_1-xM_xVO₄(M=Fe,Co,Ni) containing VO₄ tetrahedrons were synthesized by soft chemical method through a new mild liquid route. The samples sintered at 450℃ for 3h and at 650℃ for 3h are named for LT-LiNiVO₄ and for MT-LiNi_1-xM_xVO₄ respectively. All of the products were measured by X-ray diffraction, IR and Raman spectra respectively. In comparison with IR spectra of V₂O₅ and NiO, the LT-LiNiVO₄ has a strong and broad IR absorption band of VO₄ tetrahedrons located at 600～850cm^-1 with three small splitting peaks corresponding to the asymmetry stretching vibrations of V-O bonds. The results of IR and Raman spectra for MT-LiNi_1-xM_xVO₄ show that the cations of Ni²⁺, Co²⁺, Fe²⁺ have the influences on the frequency shifts of the V-O vibrations.     

Thermal and Spectral Behaviour of 5-chloro-2-methoxybenzoates of Heavy Lanthanides and Yttrium

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)₃⋅nH₂O, 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 μ_eff 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.     

氢气泡模板电沉积多孔金属镍薄膜

Porous nickel films have been successfully electrodeposited using cathodic hydrogen bubbles as a template. The influence of deposition parameters including concentration, temperature and current density on the films morphologies has been systematically studied. SEM results showed that increase in current density resulted in the deposits with higher pore density and smaller pore size. Both the pore size and thickness of the pore walls increased with the electrolyte temperature range from 20 to 60 ℃ when the other deposition parameters were fixed. Increasing the concentration of NiCl₂ or NH₄Cl in the electrolyte led to the thicker of the pore walls and declined pore size and density. The deposits displayed a dendritic morphology in cross-sectional SEM image. Electrochemical characterization of the porous nickel films after surface oxidation in 1.0 mol·L^-1 NaOH solution showed that specific capacitance as high as 7.2 F·g^-1 could be reached.     

二正丁基二硫代氨基甲酸锌配合物的量子化学研究

The geometric configurations of binuclear Zinc(Ⅱ) complex Zn₂[(n-Bu)₂NCSS]₄ and the ligand Na[(n-Bu)₂ NCSS] have been optimized by B3LYP quantum chemical method. The electronic structures have been performed by density functional theory at B3LYP/6-31G^* level. The electronic spectrums of the complex and ligand were calculated by ZINDO/S-CIS method. It is indicated from the calculation that: (1) The coordination effect of bridging ligand is bigger than that of chelating one, and the bridging ligands also translate more charge to Zn than the chelating one. (2) The calculated results about electronic spectrums are similarly to experimental measurement, and farther explain that absorption band at λ=267 nm of complex is assigned to two n → π^* transitions :one arising from the bridging ligands and the another mainly arising from the chelating ligands;but absorption band at λ=236 nm of complex is assigned to π → π^* transition which the electron mainly translates from the bridging ligands to the chelating ligands. (3) By consideration of delocalization and polar effects in coordination, the charge transfer from ligand to metal decreases the π-π and p-π conjugation effects in the chromophore group NCS₂ and to increase the energy needed for the π → π^* and n → π^* transitions, and results in the absorption bands shifting towards the short wavelength direction.     

用稀土多元渗法制备钾稀土钨青铜KxLayWO3的XPS研究

Potassium tungsten bronze K_xLa_yWO₃ (x>0.5 and y<0.01) was synthesized by rare earth co-permeation method using α-K₇[SiMg₃(OH₂)₃W₉O₃₇] as the precursor. Binding energies of La, W, O and C were determined by XPS. From the XPS data, a peak at 34.21 eV indicates that some W⁶⁺ turned into W⁵⁺ by rare earth co-permeation. The binding energies La3d were the same in the surface and inner of the composite, showing that rare earth element La could diffuse into the body of the composite and the compound of K_xLa_yWO₃ was formed at the same time. The binding energies of O1s in K_xLa_yWO₃ surface were 531.4 eV and 532.0 eV, respectively, while peak at 531.4 eV disappeared through etching process. The result implies that the binding energy of 531.4 eV was due to the adsorbent O. In addition, the binding energies of C1s in the surface were 283.5 eV, 285.0 eV and 286.7 eV respectively, while the inner had only one peak at 285.0 eV due to standard C1s. This proves that there was no C in the core.     

以Schiff碱N-丁酰基水杨酰肼为配体的三核镍(Ⅱ)配合物的合成与结构

The trinuclear nickel(Ⅱ) complex Ni₃(C₁₁H₁₁N₂O₃)₂(C₅H₅N)₄ was prepared by the reaction of Ni(OAc)₂·4H₂O with N-butylsalicylhydrazide Schiff base ligand and characterized by X-ray crystallography. The crystal belongs to triclinic， M_r=930.91， space group P1 with cell parameters a=9.8489(2)?， b=12.3110(2)?， c=18.4035(3)?， α=71.353(2)°， β=76.638(2)°，γ=84.815(2)°，V=2056.72(6)?³，Z=2，D_c=1.503g·cm^-3， μ(MoKα) =1.417mm^-1， F(000)=964， R=0.0317， wR=0.0868. A total of 5393 independent reflections were collected， of which 4448 reflections with I ≥ 2σ(I) were observed. There are two centrosymmetrical trin-uclear molecules in a unit cell， each molecule exhibits a linear trinuclear metal arrangement with the Ni…Ni…Ni angle of 180°. The interatomic distances between the nickel atoms on the two sides are 9.2030(8)? and 9.1876(9)? for the two molecules， respectively. The central nickel atom adopts an axially elongated octahedral geometry whereas the nickel atoms on the two sides have square-planar coordination environment. CCDC： 194083.     

牛血清白蛋白与两种金属配合物的作用研究

The interaction of Methylthymol Blue(MTB)-Zinc(Ⅱ) compound and Alizarin Red S(ARS)-Aluminum(Ⅲ) compound with Bovine serum albumin (BSA) was investigated by UV-Vis spectrophotometric method in acidic buffer solution. MTB-Zn(Ⅱ)-BSA was a blue color compound, which possesses maximum absorption at 613 nm with 172 nm, 174 nm and 18 nm of red shift compared to the MTB, MTB-BSA and MTB-Zn(Ⅱ) complexes respectively. Dual wavelength substantial amount ratio method, balance dialysis substantial amount ratio method and unity wavelength substantial amount ratio method were compared. The following results were obtained: the apparent molar absorptivity of MTB-Zn(Ⅱ) with BSA was ε=2.20×10⁴ L·mol^-1·cm^-1. Conditional proportion were defined, n_MTB∶n_Zn(Ⅱ)∶n_BSA=2∶2∶1; condition combination constant, K=2.07×1010. Combination proportion were defined, n_ARS∶n_Al(Ⅲ)∶n_BSA=6∶4∶1. Condition equilibrium constant of reaction of ARS-Al(Ⅲ) with BSA was K=8.80×10⁸. The apparent molar absorptivity of ε=2.65×10⁴ L·mol^-1·cm^-1. It is suggested that combination between BSA and MTB-Zn(Ⅲ) is due to coordination force. That combination between BSA and ARS-Al(Ⅲ) is due to the coordination bond and electrostatic force.     

LixNi0.8-yCo0.2ZnyOp的合成及电化学性能研究

A series of single-phase Li_xNi_0.8-yCo_0.2Zn_yO_p(0.96 ≤x≤ 1.10， 0 ≤y≤ 0.05， 2 ≤p≤ 2(1+y) ) (different in the y values) were synthesized by a two-step solid state reaction method， in which LiOH·H₂O， Zn-doped spherical Ni(OH)₂ and Co₂O₃ were used as the precursors. The ICP-AES analyses proved that the Zn-doped compounds synthesized had the nonstoichiometric form. The results of the XRD， SEM identified that the uniform particles of the as-prepared materials having a good layered structure were fine， narrowly distributed and well crystallized. The electrochemical performance test was carried out and the results showed that the as-prepared Zn-doped materials had not only a high capacity， but also a better cycling stability characterization than the un-doped one. The Li_1.06Ni_0.75Co_0.22Zn_0.03O_2.03 material has an initial reversible capacity as high as 160.5mAh·g^-1; and a first discharge efficiency 89.2%， and exhibits satisfactory cyclic stability with 90% retainable capacity after 50 cycles.     

离子层气相反应法(ILGAR)制备CuInS2薄膜的研究

CuInS₂ thin films have been prepared by ion layer gas reaction (ILGAR) using C₂H₅OH as solvent, CuCl and InCl₃ as reagents and H₂S gas as sulfuration source. The effects of cationic concentrations and numbers of cycle on the properties of CuInS₂ film were investigated. The chemical composition, crystalline structure, surface topography, deposited rate, optical and electronic properties of the films were characterized by X-ray diffractrometry (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), ultraviolet-visible spectrometry (UV-Vis) and Hall System. The results show that the crystalline of CuInS₂ thin films and the deposition rate have been improved with the increase of cationic concentration, while CuxS segregation phases appear with further increasing cationic concentration. The deposition rate is close to constant as cationic concentration is fixed. CuInS₂ thin film derived form lower cationic concentration is uniform, compact and good in adhesion to the substrates. The absorption coefficient of CuInS₂ thin films is larger than 10⁴ cm^-1, and the band gap E_g is in the range of 1.30～1.40 eV. The dark resisitivity of the thin film decreases from 50 to 10 Ω·cm and the carrier concentration ranges are over 10¹⁶ cm^-3.     

双核镍配合物[Ni2(p-PhDTA)(2,2′-bipy)2(H2O)2]·4H2O的合成与晶体结构

A novel dinuclear complex of [Ni₂(p-PhDTA)(2,2′-bipy)₂(H₂O)₂]·4H₂O (p-PhDTA^2-=para-phenylenediamine-N,N,N′,N′-tetraacetate)has been synthesized. The complex was characterized by elemental analysis, IR spectra, thermo-analysis and X-ray diffraction. The crystal belongs to triclinic, space group P1 with a=0.976 3(7)nm, b=0.989 41(7) nm, c=1.084 29(8) nm, α=65.661 0(10)°, β=75.234 0(10)°, γ=85.616 0(10)°, Z=2, V=0.925 44(12) nm³, D_c=1.568 g·cm^-3, R₁=0.031 5, wR₂=0.081 4. In the complex, the central Ni(Ⅱ) ion is coordinated in a distorted octahedral geometry, defined by two carboxyl O atoms and one N atom from same p-PhDTA^2- group, two N atoms from 2,2′-bipyridine ligand and one water molecule. The two nickel (Ⅱ) ions are linked by p-PhDTA^2- group into a dinuclear structure and extensive hydrogen bonds link the complex into a 2D supramolecular network. CCDC: 294084.     

对氟苯甲醛水杨酰腙镍(II)配合物的合成、表征及其晶体结构

A nickel(II) complex Ni(C₁₄H₁₀N₂O₂F)₂ was synthesized from p-fluorobenzaldehyde salicylhydrazone and Ni(CH₃COO)₂·4H₂O and crystallized by diffusion, the structure of which was characterized by IR spectrum, ¹H NMR, and X-ray single-crystal diffraction. The complex crystallizes in monoclinic space group C2/c with a=2.460 6(2) nm, b=0.774 1(1) nm, c=1.534 9(1) nm, β=122.300(1)°, and V=2.471 1(4), Z=8, D_c=1.541 g·cm^-3. We reported the IR, ¹H NMR, crystal structure. CCDC: 638652.