共查询到20条相似文献,搜索用时 31 毫秒
1.
P. R. Dametto B. Ambrozini A. B. Siqueira C. T. Carvalho M. Ionashiro 《Journal of Thermal Analysis and Calorimetry》2010,101(3):933-939
Solid-state Ln(L)3 compounds, where Ln stands for trivalent Tb, Dy, Ho, Er, Tm, Yb, Lu and Y, and L is 3-methoxybenzoate, have been synthesized.
X-ray powder diffractometry, infrared spectroscopy, complexometry and elemental analysis were used to characterize the compounds.
In order to study the thermal behaviour of these compounds simultaneous thermogravimetry and differential thermal analysis
(TG-DTA) and differential scanning calorimetry (DSC) were used. The results provided information on the composition, dehydration,
polymorphic transformation, thermal stability and thermal decomposition of the synthesized compounds. 相似文献
2.
A. B. Siqueira C. T. Carvalho E. Y. Ionashiro G. Bannach E. C. Rodrigues M. Ionashiro 《Journal of Thermal Analysis and Calorimetry》2008,92(3):945-951
Solid-state Ln(L)3 compounds, where Ln stands for trivalent Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and Y and L is 2-methoxybenzoate have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential
scanning calorimetry (DSC), X-ray powder diffractometry, infrared spectroscopy and complexometry were used to characterize
and to study the thermal behaviour of these compounds. The results provided information on the composition, dehydration, coordination
mode, structure, thermal behaviour and thermal decomposition. 相似文献
3.
M. L. S. De Melo N. A. Santos R. Rosenhaim A. G. Souza P. F. Athayde Filho 《Journal of Thermal Analysis and Calorimetry》2011,105(3):831-836
Solid state Ln2–L3 compounds, where Ln stands for light trivalent lanthanides (lanthanum to gadolinium), except promethium, and L is folate
(C19H17N7O6), have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning
calorimetry (DSC), X-ray powder diffractometry, infrared spectroscopy (FTIR), TG coupled to FTIR, elemental analysis and complexometry
were used to characterize and to study the thermal behaviour of these compounds. The results provided information concerning
the stoichiometry, crystallinity, ligand’s denticity, thermal stability, thermal behaviour and identification of the gaseous
products evolved during the thermal decomposition of these compounds. 相似文献
4.
E. Y. Ionashiro G. Bannach A. B. Siqueira C. T. de Carvalho E. C. Rodrigues M. Ionashiro 《Journal of Thermal Analysis and Calorimetry》2008,92(3):953-959
Solid-state Ln(2-MeO-BP) compounds, where Ln stands for trivalent Eu to Lu and Y(III) and 2-MeO-BP (which is 2-methoxybenzylidenepyruvate) have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), X-ray powder diffraction, infrared spectroscopy and other methods of analysis were used to characterize and to study these compounds. On the base of the obtained results an Ln(2MeO-BP)3·nH2O general formula can be established. 相似文献
5.
B. Ambrozini P. R. Dametto M. Ionashiro 《Journal of Thermal Analysis and Calorimetry》2011,105(3):867-871
Solid state Ln2-L3 compounds, where Ln stands for heavy trivalent lanthanides (terbium to lutetium) and yttrium, and L is tartrate [(C4H4O6)?2] have been synthesized. Simultaneous thermogravimetry and differential thermal analysis, differential scanning calorimetry, X-ray powder diffractometry, infrared spectroscopy, elemental analysis and complexometry were used to characterize and to study the thermal behaviour of these compounds. The results provided information concerning the stoichiometry, crystallinity, ligand??s denticity, thermal stability and thermal behaviour of these compounds. 相似文献
6.
B. Ambrozini P. R. Dametto A. B. Siqueira C. T. Carvalho M. Ionashiro 《Journal of Thermal Analysis and Calorimetry》2009,97(2):761-764
Solid state Ln–L compounds, where Ln stands for light trivalent lanthanides (L–Gd) and L is tartrate, have been synthesized.
Thermogravimetry and differential thermal analysis (TG/DTA), differential scanning calorimetry (DSC), X-ray powder diffractometry,
elemental analysis and complexometry were used to characterize and to study the thermal behaviour of these compounds. The
results led to information about the composition, dehydration and thermal decomposition of the isolated compounds. 相似文献
7.
J. R. Locatelli E. C. Rodrigues A. B. Siqueira E. Y. Ionashiro G. Bannach M. Ionashiro 《Journal of Thermal Analysis and Calorimetry》2007,90(3):737-746
Solid-state Ln(Bz)3·H2O compounds where Ln stands for trivalent yttrium or lanthanides and Bz is benzoate have been synthesized. Simultaneous thermogravimetry-differential
thermal analysis (TG-DTA), X-ray powder diffractometry, infrared spectroscopy and chemical analysis were used to characterize
and to study the thermal behaviour of these compounds. The results led to information about the composition, dehydration,
thermal stability and thermal decomposition of the isolated compounds. 相似文献
8.
E. Y. Ionashiro F. J. Caires A. B. Siqueira L. S. Lima C. T. Carvalho 《Journal of Thermal Analysis and Calorimetry》2012,108(3):1183-1188
Characterization, thermal stability and thermal decomposition of light trivalent lanthanide fumarates, as well as, the thermal behaviour of fumaric acid and its sodium salt were investigated employing simultaneous thermogravimetry and differential thermal analysis, differential scanning calorimetry, Fourier transform infrared spectroscopy (FTIR), TG?CFTIR techniques, elemental analysis and complexometry. On heating, sublimation of fumaric acid is observed, while the thermal decomposition of the sodium fumarate occurs with the formation of a mixture of sodium carbonate and carbonaceous residue. The thermal decomposition of light trivalent lanthanide fumarates occurs in consecutive and/or overlapping steps with the formation of the respective oxides: CeO2, Pr6O11, and Ln2O3 (Ln?=?La, Nd, Sm, Eu, Gd). 相似文献
9.
A. B. Siqueira C. T. de Carvalho E. C. Rodrigues E. Y. Ionashiro G. Bannach M. Ionashiro 《Journal of Thermal Analysis and Calorimetry》2010,100(1):95-100
Solid-state Ln–L compounds, where Ln stands for heavy trivalent lanthanides or yttrium (III) (Tb–Lu, Y) and where L is pyruvate,
have been synthesized. Thermogravimetry and derivative thermogravimetry (TG/DTG), differential scanning calorimetry (DSC),
X-Ray powder diffractometry, infrared spectroscopy, elemental analysis and complexometry were used to characterize and to
study the thermal behaviour of these compounds. The results led to information about the composition, dehydration, thermal
behaviour, ligand denticity of the isolated complexes. 相似文献
10.
F. J. Caires L. S. Lima D. J. C. Gomes A. C. Gigante O. Treu-Filho M. Ionashiro 《Journal of Thermal Analysis and Calorimetry》2013,111(1):349-355
Solid-state LnL3·1.25H2O compounds, where L is oxamate and Ln is light trivalent lanthanides, have been synthesized. Simultaneous thermogravimetry and differential scanning calorimetry (TG–DSC), experimental and theoretical infrared spectroscopy, TG–DSC coupled to FTIR, elemental analysis, complexometry, and X-ray powder diffractometry were used to characterize and to study the thermal behavior of these compounds. The results led to information about the composition, dehydration, thermal stability, thermal decomposition, and gaseous products evolved during the thermal decomposition of these compounds in dynamic air atmosphere. The dehydration occurs in a single step and through a slow process. The thermal decomposition of the anhydrous compounds occur in a single (Ce), two (Pr), and three (La, Nd to Gd) steps with the formation of the respective oxides, CeO2, Pr6O11, and Ln2O3 (Ln = La, Nd to Gd). The theoretical and experimental spectroscopic study suggests that the carboxylate group and amide carbonyl group of oxamate are coordinate to the metals in a bidentate chelating mode. 相似文献
11.
Liquid crystalline complexes of the formula [Ln(LH)3(DOS)3] have been synthesized, where Ln is a trivalent rare earth-ion (Y, La-Lu, except Pm), LH is the ligand N-octadecyl-4-tetradecyloxysalicylaldimine and DOS is the dodecyl sulphate counterion. Although the Schiff 's base ligands do not exhibit mesomorphism, the complexes do (SmA phase). The mesophase behaviour of these compounds has been investigated by polarizing optical microscopy, differential scanning calorimetry, high temperature X-ray diffraction and thermogravimetric analysis. The stoichiometry of the complexes remains constant throughout the lanthanide series. 相似文献
12.
In vitro antimicrobial and antioxidant evaluation of rare earth metal Schiff base complexes derived from threonine 下载免费PDF全文
Lekha Logu Kanmani Raja Kamatchi Hariharan Rajmohan Sathish Manohar Rajagopal Gurusamy Easwaramoorthi Deivanayagam 《应用有机金属化学》2015,29(2):90-95
Six novel Ln(III) Schiff base complexes were synthesized using rare earth metals with threonine and 5‐bromosalicylaldehyde, namely Pr(III), Sm(III), Gd(III), Tb(III), Er(III) and Yb(III) Schiff bases. These complexes were characterized using elemental analysis, molar conductivity, Fourier transform infrared and UV–visible spectroscopies, and thermogravimetry–differential thermal analysis. The general formula of the complexes is [Ln(L)(NO3)2(H2O)].NO3 (L = Schiff base ligand). The spectroscopic data reveal that the Schiff base ligand behaves as a tridentate ligand with ONO donor atoms sequencing towards the central metal ion. An investigation of fluorescence properties of the Sm(III), Er(III) and Tb(III) complexes shows that the Ln(III) ions can be sensitized efficiently by the ligand to some extent. Antimicrobial activity testing indicates that all six complexes exhibit antibacterial and antifungal ability against microbes with broad antimicrobial spectra. In addition, the antioxidant properties of the complexes were also screened. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
13.
Patrícia R. Dametto Beatriz Ambrozini Adriano B. Siqueira Cláudio T. Carvalho Massao Ionashiro 《Journal of Thermal Analysis and Calorimetry》2009,97(2):765-768
Solid-state Ln–C8H7O3 compounds, where Ln stands for Eu(III) and Gd(III) and C8H7O3 is 3-methoxybenzoate, have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential
scanning calorimetry (DSC), X-ray powder diffractometry, infrared spectroscopy, elemental analysis and complexometry were
used to characterize and to study the thermal behaviour of these compounds. The results led to information about the composition,
dehydration, thermal stability and decomposition of the isolated compounds. 相似文献
14.
三价轻希土—PMBP—路易斯碱三元配合物的合成及其性质的研究 总被引:1,自引:2,他引:1
合成了1—苯基—3—甲基—4—苯甲酰基—吡唑啉酮—5(PMBP)和路易斯碱的三价轻希土三元配合物LnA_3·L(A=Pmbp~-;L=C_2H_5OH时,Ln=La、Pr、Sm、对Gd为GdA_3·(C_2H_5OH)_(0·25);L=Phen(邻菲罗啉)时,Ln=Pr-Gd,L=TBPO(三丁基氧化膦)时,Ln=La、Pr—Gd)。测定了它们的摩尔电导值、热谱、红外光谱、可见—紫外光谱、荧光光谱和质子核磁共振谱。观察到热稳定性次序为LnA_3·Phen>LnA_3·TBPO。从同类型配合物系列的热效应值、LnA_3·Phen型配合物的合成难易程度及其紫外最大吸收波长的移动可观察到镧系收缩现象。 相似文献
15.
A. B. Siqueira G. Bannach E. C. Rodrigues C. T. Carvalho M. Ionashiro 《Journal of Thermal Analysis and Calorimetry》2008,91(3):897-902
Solid-state LnL3 compounds, where L is 2-methoxybenzoate and Ln is light trivalent lanthanides, have been synthesized. Thermogravimetry (TG), differential scanning calorimetry (DSC), X-ray
powder diffractometry, infrared spectroscopy and elementary analysis were used to characterize and to study the thermal behaviour
of these compounds. The results led to information on the composition, dehydration, thermal stability and thermal decomposition
of the isolated compounds. On heating these complexes decompose in three (Ce, Pr) or five (La, Nd, Sm) steps with the formation
of the respective oxide: CeO2, Pr6O11 and Ln2O3 (Ln=La, Nd, Sm) as final residues. The theoretical and experimental spectroscopic study suggests predominantly the ionic bond
between the ligand and metallic center. 相似文献
16.
Juan Luo Congzhi Wang Jianhui Lan Qunyan Wu Yuliang Zhao Zhifang Chai Changming Nie Weiqun Shi 《中国科学:化学(英文版)》2016,59(3):324-331
Separation of trivalent lanthanides (Ln(III)) and actinides (An(III)) is a key issue in the advanced spent nuclear fuel reprocessing. In the well-known trivalent actinide lanthanide separation by phosphorus reagent extraction from aqueous komplexes (TALSPEAK) process, the organophosphorus ligand HDEHP (di-(2-ethylhexyl) phosphoric acid) has been used as an efficient reagent for the partitioning of Ln(III) from An(III) with the combination of a holdback reagent in aqueous lactate buffer solution. In this work, the structural and electronic properties of Eu3+ and Am3+ complexes with HDEHP in nitric acid solution have been systematically explored by using scalar-relativistic density functional theory (DFT). It was found that HDEHP can coordinate with M(III) (M=Eu, Am) cations in the form of hydrogen-bonded dimers HL2- (L=DEHP), and the metal ions prefer to coordinate with the phosphoryl oxygen atom of the ligand. For all the extraction complexes, the metal-ligand bonds are mainly ionic in nature. Although Eu(III) complexes have higher interaction energies, the HL2- dimer shows comparable affinity for Eu(III) and Am(III) according to thermodynamic analysis, which may be attributed to the higher stabilities of Eu(III) nonahydrate. It is expected that this work could provide insightful information on the complexation of An(III) and Ln(III) with HDEHP at the molecular level. 相似文献
17.
The thermal decomposition of lanthanide complexes, with a general formula: [LnL(NO3)2](NO3), where Ln = La, Pr, Nd, Sm, Gd, Tb, Dy, and Er; and L = bis-(salicyladehyde)-1,3-propylenediimine Schiff base ligand, was studied by thermogravimetric (TG) and derivative thermogravimetric (DTG) techniques. The TG and DTG data indicated that all complexes are thermostable up to 398 K. The thermal decomposition of all Ln(III) complexes was a two-stage process and the final residues were Ln2O3 (Ln = La, Nd, Sm, Gd, Dy, Er), Tb4O7, and Pr6 O11. The activation energies of thermal decomposition of the complexes were calculated from analysis of the TG-DTG curves using the Kissinger, Friedman, and Flynn-Well-Ozawa methods. 相似文献
18.
F. S. Alves L. H. Bembo F. J. Caires E. Y. Ionashiro 《Journal of Thermal Analysis and Calorimetry》2013,113(2):739-744
Solid-state heavier lanthanides fumarates compounds have been synthesized, and the compounds were characterized by employing simultaneous thermogravimetry and differential thermal analysis (TG–DTA), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), TG coupled to FTIR, elemental analysis, and complexometry. On heating, the dehydration occurs in a single and two consecutive steps and the thermal decomposition of the anhydrous compounds occurs in consecutive and/or overlapping steps, with formation of the respective oxides: Tb4O7 and Ln2O3 (Ln=Dy to Lu). The results also led to information about composition, thermal behavior, and the type of coordination of the isolated compounds. 相似文献
19.
镅离子在溶液中主要以三价形式(Am(III))存在,因其离子半径与三价镧系离子Ln(III)接近,化学特性相似,使得Am(III)与Ln(III)的有效分离被认为是核燃料循环领域最具挑战性的课题之一。利用镅的多价态特性,采用不同氧化方法可将Am(III)氧化成高价态的AmO_2~+和AmO_2~(2+)形式,再通过溶剂萃取、沉淀等方法进行分离,是实现Am与Ln分离的一种新思路。本文综述了不同氧化方法对水溶液环境中Am(III)的氧化分离研究进展,描述了相关机理,指出了不同氧化方法的优劣并展望了未来发展趋势,以期为发展新型镧系与锕系元素分离技术提供参考。 相似文献
20.
E. G. Afonin 《Russian Journal of General Chemistry》2002,72(3):368-370
Addition of a KOH solution to aqueous solutions containing methanephosphonic acid H2L andrare-earth ions Ln3
+ results in crystallization of LnHL2 (Ln = La-Er, Y), KLn3H6L8 (Ln = Yb, Lu); Tmforms the salts of both types. The solubility and thermal stability of the products were studied. 相似文献