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Journal of Radioanalytical and Nuclear Chemistry
Authors: M. Kumar Raju, P. Sugathan, T. Seshi Reddy, B. Thirumala Rao, S. Muralithar, R. Singh, R. Bhowmik, and P. Madhusudhana Rao

Abstract  

The high spin level structure of 73As nucleus is studied by populating the nucleus in 64Ni(12C,p2n)73As reaction. Level scheme is revised significantly. Positive parity sequence is extended up to 33/2+ and a negative parity side band is identified and extended up to high spins 37/2. In addition about 15 new energy levels and a total of about 25 new gamma transitions were placed in the level scheme.

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Journal of Thermal Analysis and Calorimetry
Authors: Aliakbar Dehno Khalaji, Sepideh Maghsodlou Rad, Gholamhossein Grivani, and Debasis Das

properties of ligand and complexes were proposed based on elemental analyses: FT-IR, UV–Vis, 1 H-NMR spectroscopy, and thermal analysis. From the FT-IR spectra, it was concluded that the ligand is an anionic bidentate NO chelating and is coordinated to the

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Journal of Thermal Analysis and Calorimetry
Authors: Vadim V. Krongauz, Yann-Per Lee, and Anthony Bourassa

upon dehydrochlorination absorb light strongly above 320 nm [ 6 , 9 , 10 , 13 , 14 , 21 , 22 , 24 ], therefore, kinetics of PVC degradation can be monitored specifically using UV–visible spectroscopy. Some loss of conjugation may occur through

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Abstract  

Mössbauer spectroscopy is a dynamic field with applications ranging from physics to biology. This paper gives a review of Mössbauer spectroscopy activities carried out by different groups in China. About thirty groups are distributed all over China for both fundamental and practical aspects. In-beam Mössbauer setup was established at HIRAC accelerator in Lanzhou, and the nuclear scattering facility has already been planned at Shanghai Synchrotron Radiation Light Source. In this review, some recent developments and achievements are discussed, as examples: (1) Brownian motion in anisotropic media, (2) applications to archaeology, and (3) molecule-based magnetic materials.

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Journal of Thermal Analysis and Calorimetry
Authors: Marieta Muresan-Pop, Irina Kacsó, Carmen Tripon, Z. Moldovan, Gh Borodi, S. Simon, and I. Bratu

diffraction, FTIR, 13 C NMR, 15 N NMR, X-ray photoelectron spectroscopy (XPS), thermal analysis, and mass spectrometry. The chosen methods demonstrate the formation of the ambazone hydrochloride compound. Experimental

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Summary  

This review considers analytical possibilities of Mössbauer spectroscopy in biomedical research. The results of various biomedical applications of Mössbauer spectroscopy were grouped as quantitative and qualitative studies of biological molecules during molecular diseases, studies of the effect of environmental factors on biological molecules, studies of metabolic processes with Mössbauer elements, studies of dynamic properties, studies of pharmaceuticals containing Mössbauer elements. These results demonstrate wide possibilities of Mössbauer spectroscopy in analysis of various biologically important species for obtaining information about the molecular nature of diseases and pathological processes.

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Abstract  

Synthesis, spectroscopic characterization and thermal analysis of the [Pd(dmba)(Cl)(iso)] (1), [Pd(dmba)(NCO)(iso)] (2), [Pd(dmba)(N3)(iso)] (3) and [Pd(dmba)(Br)(iso)] (4) (dmba = N,N′-dimethylbenzylamine; iso = isonicotinamide) compounds are described in this work. The complexes were investigated by infrared spectroscopy (IR), differential thermal analysis (DTA) and thermogravimetry (TG) and the residues of the thermal decomposition were identified as Pdo by X-ray powder diffraction. The thermal stability order of the complexes varied as [Pd(dmba)(Cl)(iso)] (1) > [Pd(dmba)(Br)(iso)] (4) > [Pd(dmba)(NCO)(iso)] (2) > [Pd(dmba)(N3)(iso)] (3).

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Abstract  

The application of UV-Vis and time-resolved laser-induced fluorescence (TRLF) spectroscopies to direct speciation of uranium(VI) in environmental samples offers various prospects that have, however, serious limitations. While UV-Vis spectroscopy is probably not sensitive enough to detect uranium(VI) species in the majority of environmental samples, TRLFS is principially able to speciate uranium(VI) at very low concentration levels in the nanomol range. Speciation by TRLFS can be based on three parameters: excitation spectrum, emission spectrum and lifetime of the fluorescence emission process. Due to quenching effects, the lifetime may not be expected to be as characteristic as, e.g., the emission spectrum. Quenching of U(VI) fluorescence by reaction with organic substances, inorganic ions and formation of carbonate radicals is one important limiting factor in the application of U(VI) fluorescence spectroscopy. Fundamental photophysical criteria are illustrated using UV-Vis and fluorescence spectra of U(VI) hydrolysis and carbonato species as examples.

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Abstract  

The preparation, spectroscopic characterization and thermal stability of neutral complexes of uranyl ion, UO2 2+, with phosphonate ligands, such as diphenylphosphonic acid (DPhP), diphenyl phosphate (DPhPO) and phenylphosphonic acid (PhP) are described. The complexes were prepared by a reaction of hydrated uranyl nitrate with appropriate ligands in methanolic solution. The ligands studied and their uranyl complexes were characterized using thermogravimetric and elemental analyses, ESI-MS, IR and UV–Vis absorption and luminescence spectroscopy as well as luminescence lifetime measurements. Compositions of the products obtained dependent on the ligands used: DPhP and DPhPO form UO2L2 type of complexes, whereas PhP forms UO2L complex. Based on TG and DTG curves a thermal stability of the complexes was determined. The complexes UO2PhP·2H2O and UO2(DPhPO)2 undergo one-step decomposition, while UO2PhP · 2H2O is decomposed in a two-step process. The thermal stability of anhydrous uranyl complexes increases in the series: DPhPO < PhP < DPhP. Obtained IR spectra indicate bonding of P–OH groups with uranyl ion. The main fluorescence emission bands and the lifetimes of these complexes were determined. The complex of DPhP shows a green uranyl luminescence, while the uranyl emission of the UO2PhP and UO2(DPhPO)2 complexes is considerably weaker.

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Progress in Agricultural Engineering Sciences
Authors: Marina Vranić, Mladen Knežević, Zsolt Seregély, Krešimir Bošnjak, Josip Leto, and Goran Perčulija

Blanco, M., Coello, J., Iturriaga, H., Maspoch, S., Gonzalez, R. (1998) Determination of water in lubricating oils by mid- and near-infrared spectroscopy. Microchim. Acta 128: 235. Determination of water in lubricating oils by

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