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Summary  

The Iron Age ceramic technology used in the manufacturing of cooking pots was studied by thermo-FTIR spectroscopy analysis. The pottery was excavated at Tel Hadar on the eastern shore of the Sea of Galilee. The results demonstrate that the cooking pots were manufactured using noncalcareous or slightly calcareous raw material proceeds from soil. The firing was at about 750-850C and the cementation to ceramic was obtained by low temperature sintering of the clay. The use of soil raw material composed of smectitic (montmorillonitic) clay enabled the low temperature sintering. The clay from soil is relatively poorly crystallized and rich in natural iron oxide, both of which induce earlier sintering. Most of the cooking pots were tempered with broken pieces of large calcite crystals that were added to the clayey raw material from an additional source. Alternative tempering with limestone particles composed of polycrystalline calcite is inappropriate as it brings about earlier and intense decarbonation during the firing, which causes defects in the pots.

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Abstract  

Heavy metals like the actinides possess a high risk potential to the environment not only because of their radiotoxicity but also due to their chemical toxicology. Uranium as one of the major actinide elements has to be considered in particular. Under reducing conditions, tetravalent uranium occurs primarily in the environment. To date, a lack of appropriate analytical techniques that featured sufficient sensitivity made it difficult to study the aqueous phosphate chemistry of uranium(IV) as such complexes show only low solubility. A novel time-resolved laser fluorescence spectroscopy system was set up recently and optimized to do research on uranium(IV). By application of this laser system we could successfully study uranium(IV) phosphate in concentration ranges where no precipitation or formation of colloids occurred. At pH = 1.0, U4+ and one uranium(IV) phosphate complex existed in parallel in aqueous solution. The complex could be identified as [U(H2PO4)]3+. Determination of its corresponding complex formation constant via two different evaluation methods resulted in the finding of (1)
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\log \beta_{121}^{ \circ } = 2 6. 3 7 \pm 0. 7 6$$ \end{document}
and (2)
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\log \beta_{121}^{ \circ } = 2 6. 4 3 \pm 0. 2 3$$ \end{document}
. Both values prove that [U(H2PO4)]3+ is a very stable complex in solution under experimental conditions. As they are in very good agreement with each other, the total complex formation constant was determined by means of the weighted average out of (1) and (2). It was calculated to be
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\log \beta_{121}^{ \circ } = 2 6. 4 2 \pm 0. 2 2$$ \end{document}
.
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Abstract  

For the positional isotopic analysis of tritium-labelled organic compounds which are isolated at the end of a tracer experiment, it is proposed to render high-resolution triton-NMR spectroscopy sufficiently sensitive as follows. Andrew's rotating magnetic field is used to narrow the NMR lines that are detected by observing the anisotropy of the β-radiation of the sample which is kept at 0.01 °K by a helium-dilution refrigerator. In this context, the usefulness of the rotating magnetic field for cryogenic proton-NMR spectroscopy is pointed out.

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UV-cured (ultra violet), water-based and epoxyphenolic lacquers have been characterized as coatings for possible application in vegetable canning industry. These lacquers were applied to three different types of tinplates and tin free steel (TFS). The behaviour of lacquers was monitored applying porosity, flexibility and infrared (IR) reflectance spectroscopy tests. With IR reflectance spectroscopy test, we were able to determine the composition of lacquers. Using porosity and flexibility tests, performed by electrochemical methods, it was possible to characterize the best lacquer for food canning. In this work the variables involved in lacquering, e.g. the weight of coating and the degree of polymerization of lacquers were also taken into account.

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elemental analysis as input data, which requires expensive chromatographic analysis [ 13 ]. However, Fourier transform infrared (FTIR) spectroscopy, either mid-IR (MIR) or near-IR (NIR), are among the most trusted analytical techniques in monitoring

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useful in controlling quality changes in food during processing and in storage [ 10 , 11 ]. IR spectroscopy, on the other hand, serves as an established method to determine types and number of chemical bonds present in a sample and therefore it can be

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Abstract  

Instrumental neutron activation, atomic absorption spectroscopy and conventional methods of analysis were used on eight different silicate rocks and two minerals. Trace elements and major constituents were determined. It was considered that the methods should be regarded as complementary analytical techniques.

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Abstract  

Valency changes of iron and tin in framework-substituted microporous and mesoporous molecular sieves (Fe-ETS-10, Fe-ZSM-5, Fe-AlPO-11, Sn-ZSM-12 and Sn-MCM-41) have been studied under reducing and oxidizing conditions by in situ Mössbauer spectroscopy. It is demonstrated that the structure of the host matrices strongly influences the stabilization and the oxidation state of the ions. Debye temperature, D, data also are estimated, they support the suggested structural assignment of various species.

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Summary  

Temperature induced magnetic phase transition in the interstitial compound LaFe11.6Si1.4C0.2 was studied by zero-field Mössbauer spectroscopy. A paramagnetic doublet and a magnetically split sextet co-existed in the zero-field spectra in the temperature region of 213-218 K, and a thermal hysteresis was observed in the heating and cooling cycles. The spectra indicate that the magnetic phase transition induced by temperature is of first order for this sample.

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Abstract  

57Fe Mössbauer spectroscopy was used to study57Fe doped high Tc TlBaCaCuO4.5+y superconductor between 70 and 295 K. Significant anomalous changes in the shape of the Mössbauer spectrum were observed around the Tc /105–120 K/. This experimental fact could be reproduced. Our finding can be associated with structural changes taking place around the Tc in TlBaCaCuO4.5+y superconductor.

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