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Effects of Gd^(3+) on Luminescence Properties of Eu^(3+) within Polymeric Structure in Aqueous Solutions

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Journal of Rare Earths 2001年第1期19卷 11-14页

作者：尹显洪史华红陈小明古练权 dept. of chem. Zhongshan Univ. Guangzhou 510275 China

?6′ tetracarboxy 4,4′ bipyridine was synthesized and the luminescence enhancement of their Eu 3+ complexes by Gd 3+ was observed. The results indicate that the mechanism of enhancement is based on the formation of a polymeric structure where Eu 3+ and Gd 3+ are linked together by the ligands, which favours the consequent transfer of absorbed energy along the polymeric chain through several ligands toward the Eu 3+ .

关键词： rare earths europium complex intramolecular energy transfer co luminescence

Synthesis and Crystal Structure of Binuclear Ytterbium Complex with Isonicotinoyl Hydrazone

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Journal of Rare Earths 2001年第2期19卷 86-89页

作者：卜显和鹿守亮陈巍张若桦 dept. of chem. Nankai Univ. Tianjin 300071 China

The ytterbium complex of isonicotinoyl hydrazone was synthesized and the structure was determined by X-ray diffraction analysis. The crystal and molecular structure of the title complex [Yb-2(L)(3)](OH)(3) shows that the complex has two identical nine-coordinated ytterbium ions with each surrounded by N3O6 donor set, Two ytterbium ions are bridged by three phenolate oxygen atoms, The geometry around each ytterbium ions can be considered as a three-capped trigonal prism.

关键词： rare earths synthesis ytterbium complex isonicotinoyl hydrazone crystal structure

Enthalpies of Solution of Complexes of Rare Earth Nitrate with L-α-Histidine in Water

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Journal of Rare Earths 2002年第5期20卷 424-426页

作者：刘洋房艳高胜利陈三平史启祯 Lab. of Phys.-Inorg. chem. Dept. of Chem. Northwest Univ. Xi'an 710069 China

The enthalpies of solution in water of complexes of RE(NO 3) 3 (RE=La～Nd, Sm～Lu, Y) with L α Histidine (His) were measured at 298.15 K. The standard enthalpies of formation of RE(His) 3+ (aq) were calculated. The 'tetrad effect' regularity was observed from the curve, which is the enthalpies of solution plotted against the atomic numbers of the elements in lanthanide series.

关键词： rare earths histidine enthalpy of solution

The Simultaneous Determination of Cu Ph Cd and Sb by Derivative Adsorption Chronopotentiometry

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Chinese chem.cal Letters 2000年第9期11卷 807-808页

作者： Xiao Li ZHANG Shu Ying PAN Department of chem.stry Shandong University, Jinan 250100 dept. of chem. Shandong University Jinan 250100 China

The behaviour of the complexes of copper,lead,cadmium and antimony with salicylfluorone (SAF) adsorbed on HMDE has been investigated by derivative chronopotentiometry in NH_3/NH_4C1. The dependence of the peak height on the dt/dE vs E curve on preconcentration time, the pH of solution and the constant reducing current are discussed. This method achieved the simultaneous determination of copper, lead, cadmium and antimony in human hair.

关键词： Simultaneous determination Cu,Pb,Cd,Sb complex chronopotentiometry.

CORROSION MONITORING OF LY12 IN SODIUM CHLORIDE SOLUTION WITH ELECTROchem.CAL NOISE TECHNIQUE

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Acta Metallurgica Sinica(English Letters) 2001年第2期14卷 91-96页

作者： J.Q. Zhang, Z. Zhang, J.M. Wang, H.B. Shao and C.N. Cao (Department of chem.stry, Zhejiang University , Hangzhou 310027, China) (State Key Laboratory for Corrosion and Protection of Metals, Institute of Metal Research, The Chinese Academy of Sciences, She dept. of chem. Zhejiang Univ. Hangzhou 310027 China

Spontaneous electrochem.cal noise (EN) can be a rich source of information concerning the processes simultaneously occurring on a corroding interface. But the noise signal is often difficult to be analyzed due to the complicated nature of the specific systems being investigated. In this paper, the potential noise fluctuations during the free corrosion of commercial aluminum alloy LY12 in sodium chloride solution was recorded and analyzed with different techniques. The typical results showed that the fractal dimension (D,n) obtained from spectral power density (SPD) is mainly directly proportional to the intensity of pitting corrosion and to the value of pitting parameter (SE) derived from dimensional analysis, while the fractal dimension (DE) obtained from EIS is mainly related to the uniform corrosion.

关键词： electrochem.cal noise fractal stochastic analysis dimensionanalysis localized corrosion

ELECTROchem.CAL NOISE ANALYSIS OF PURE ALUMINUM IN SODIUM CHLORIDE SOLUTION WITH WAVELET TRANSFORM TECHNIQUE

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Acta Metallurgica Sinica(English Letters) 2002年第3期15卷 272-278页

作者： Z. Zhang, Q.D. Zhong, J.Q. Zhang, Y.L. Cheng, F.H. Cao, J.M. and C.N. CaoDepartment of chem.stry, Zhejiang University, Hangzhou 310027, ChinaElectrochem.cal Research Group, Shanghai University of Electric Power, Shanghai 200090, ChinaState Key Laboratory dept. of chem. Zhejiang Univ. Hangzhou 310037 China

Wavelet transforms (WT) are proposed as an alternative tool to overcome the limitations of Fourier transforms (FFT) in the analysis of electrochem.cal noise (EN) data. The most relevant feature of this method of analysis is its capability of decomposing electrochem.cal noise records into different sets of wavelet coefficients, which contain information about the time scale characteristic of the associated corrosion event. In this context, the potential noise fluctuations during the free corrosion of pure aluminum in sodium chloride solution was recorded and analyzed with wavelet transform technique. The typical results showed that the EN signal is composed of distinct type of events, which can be classified according to their scales, i.e. their time constants. Meanwhile, the energy distribution plot (EDP) can be used as 'fingerprints' of EN signals and can be very useful for analyzing EN data in the future.

关键词： electrochem.cal noise wavelet analysis Fourier transforms corrosion pure aluminum

EIS STUDY ON ZINC RICH PAINTS IN 3.5% NaCl SOLUTION BY DOUBLE-CELL TEST

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Acta Metallurgica Sinica(English Letters) 2002年第3期15卷 299-306页

作者： DM. Xie, J.M. Hu, J.M. Wang and J.Q. ZhangDepartment of chem.stry, Zhejiang University, Hangzhou 310027, ChinaState Key Laboratory for Corrosion and Protection of Metals, Institute of Metal Research, The Chinese Academy of Sciences, Shenyang 110016, China dept. of chem. Zhejiang Univ. Hangzhou 310027 China

This paper discussed the possibility of obtaining electrochem.cal impedance spectroscopy (EIS) responses of zinc rich paints (ZRP) using serial double-cell (SDC). The influence of counter electrode was outlined. An equivalent circuit (ES) for the double-cell was then discussed. The relationship between EC, the time constant, the parameters in EC of SDC and those of two single sells was discussed. The results gained by serial double cell test are consistent with those of single cell test. It can be concluded that double cell test method can be used to study ZRP completely.

关键词： Electrodes Equivalent circuits Sodium chloride Spectroscopy Zinc

Photophysical Property of Ternary Complex Eu(DPHA)_3·Phen·2H_2O

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Journal of Rare Earths 2001年第3期19卷 172-176页

作者：王明召王淑贤蔡冠梁 dept. of chem. Beijing Normal Univ. Beijing 100875 China

One ternary complex of europium with the plant growth regulator HDPHA (2-Hydroxydiphenyl acetic acid) and Phen (1,10-Phenanthroline), Eu(DPHA) 3·Phen·2H 2O, was synthesized and characterized by the elemental analysis and DTA-TG measurement. The photophysical property of the complex was investigated by means of IR spectra, Raman spectrum and laser-exited, high-resolved excitation and emission spectra as well as time-resolved luminescence spectra. The luminescence spectra reveal four Eu 3+ sites with energy difference within 25 cm -1 and local symmetries of C 1 or C 2 or C s in the complex. The energy transfer among the Eu 3+ sites is observed. The 7F J sublevel splitting of the Eu 3+ ion is discussed.

关键词： rare earths europium ternary complex photophysical property Eu 3+ sites

Synthesis and Structural Characterization of Adduct [La(NO_3)_3·4H_2O]·2(BQEB)

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Journal of Rare Earths 2001年第1期19卷 1-5页

作者：朱文祥苟宝迪张永安李言陈学安 dept. of chem. Beijing Normal Univ. Beijing 100875 China

New podand compound 1,2 bis (8′ quinolyloxy ethoxy) benzene (BQEB) was prepared. A lanthanum adduct with BQEB was synthesized and its structure was characterized by X ray crystal analysis using Mo Kα radiation ( λ =0 071073 nm). Crystal data: space group C2/c, Z=4, a =1 8636(3) nm, b =2 0036(3) nm, c =1 5186(3) nm, α =90 00°, β =91 452(14)°, γ =90 00°, R f=0 0373 for 6520 observed data. In the crystal structure the La 3+ is ten coordinated by three NO - 3 and four H 2O. Two podand molecules link to the coordination core via O—H…N (average O…N=0 2766(3) nm) hydrogen bonds. The adduct has a one dimensional chain sandwich structure consisting of every two podand molecules with a [La(NO 3) 3·4H 2O] as a bridge. The whole crystal is packed in a manner of…LLMLLMLL….

关键词： rare earths podand lanthanum adduct sandwich structure