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Journal of Thermal Analysis and Calorimetry
Authors: A. Dąbrowski, E. Mendyk, E. Robens, K. Skrzypiec, J. Goworek, Mariola Iwan, and Zofia Rzączyńska

Abstract  

We investigated lunar regolith collected during the Apollo 11, 12 and the Apollo 16 missions. The Apollo 11 and the Apollo 12 samples come from the lunar mare, whereas the Apollo 16 expedition brought back material from a highland region of the near side of the Moon. In paper series we summarise in brief the results of measurements using photoelectron spectroscopy (XPS), Raman spectroscopy, X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), nitrogen adsorption, thermal analysis (TG, DTA) and temperature-programmed reduction and oxidation (TPRO) method. Parts of samples were examined by means of scanning electron (SEM/EDS) and atomic force microscopy (AFM).

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Abstract  

The elemental compositions of Apollo 11 and Apollo 12 lunar soil samples 10084,141 and 12070,83 and Apollo 12 rock fragment 12063,73 were determined by non-destructive radioanalytical methods. Main mineral fractions and glasses separated from these samples were analyzed as well. Instrumental neutron activation analysis (INAA) was used to determine Na, Mg, Al, Si, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zr, Cs, Ba La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb, Lu, Hf, Ta, W, Ir, Au, Th and U. A method of delayed neutron counting was used for the determination of uranium, and non-dispersive radioisotopic X-ray fluorescence analysis was applied to the determination of Ti, Fe, Sr, Y and Zr.

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Abstract  

Recently we published results of investigations of the surface properties of three lunar soil samples from the Apollo 11, 12 and 16 missions. In the present paper we summarise and supplement the results of measurements of density using a helium pycnometer, krypton and nitrogen adsorption using volumetric techniques and of water, heptane and octane adsorption using gravimetric techniques. We present additional diagrams and electron micrographs.

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Abstract  

Re-examination of a vast amount of lead and xenon isotope data that have been accumulated since the Apollo 11 landing on the moon in July 1969 reveals that some of the lunar fines and breccia started to retain their radiogenic lead and fissiogenic xenon isotopes about 5 billion years ago when the ratios of235U and244Pu to238U in the early solar system were approximately 4 and 2 atoms per 10 atoms of238U, respectively.

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Résumé  

Pour déterminer 44 éléments dans des échantillons lunaires on a fait appel à l'analyse instrumentale par activation neutronique et à l'analyse par activation neutronique utilisant des séparations chimiques et la spectrométrie gamma à haute résolution. Si on utilise ces méthodes conjointement à la spectrométrie de masse à étincelle, on détermine plus de 56 éléments avec une certitude moyenne de 10%. On compare les résultats de l'analyse de sols lunaires rapportés par Apollo 11, 12, 14, 15 et 16 et par Luna 16.

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Résumé  

On applique l'activation neutronique aux mesures d'abondance isotopique du rhénium dans les matériaux lunaires. On y parvient en comparant les activités induites par (n, γ) de186Re et188Re au moyen des raies γ de respectivement 137 et 155 keV. Afin d'éviter les interférences, (spécialement celles de199Au et99mTc) on a besoin d'un procédé conduisant à une grande pureté radiochimique. De plus, on détermine les teneurs en rhénium et tungstène. On a remarqué une anomalie isotopique du rhénium dans les échantillons d'Apollo-14, montrant un enrichissement remarquable en187Re (de 1,4 à 1,8% dans les sols et jusqu'à 29% dans les brèches). On montre enfin que cet enrichissement est partiellement dû à l'irradiation neutronique sur la surface lunaire par la réaction186W(n,γ)187W

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187Re. Cependant, l'anomalie observée, causée principalement par les neutrons intermédiaires, n'est pas produite uniquement par les neutrons lunaires. L'activation d'un réacteur y contribue aussi par la réaction:186W(n,γ)187W
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187Re(n,γ)188Re, qui peut être corrigée par l'analyse d'étalons de tungstène irradiés simultanément. On estime que la contribution lunaire à l'enrichissement du187Re est de 20 à 60% de l'excès total observé.

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Introduction The lunar samples of Apollo missions were investigated and presented in detail in the article [ 1 ]. From the studies of surface properties of lunar regolith from Apollo 11 (mare), 12 (mare) and 16 (highland

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Acta Chromatographica
Authors: Samiuela Lee, Christa E. Nath, Ben W. R. Balzer, Craig R. Lewis, Toby N. Trahair, Antoinette C. Anazodo, and Peter J. Shaw

) detector (SPD-M30A). Data collection and integration were accomplished using Shimadzu Labsolutions software. The wavelength of detection was at 339 nm. Separation of analytes was performed using an Alltech Apollo 4.6 mm × 250 mm, 5-μm RP-C18 column

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measured using the APOLLO console (Tecmag) and the 7 T/89 mm superconducting magnet (Magnex). A Bruker HP-WB high speed MAS probe equipped with the 4 mm zirconia rotor and the KEL-F cap was used to spin the sample at 8 kHz. The resonance frequency was equal

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Journal of Thermal Analysis and Calorimetry
Authors: Cristina Bucur, Mihaela Badea, Calu Larisa, Dana Marinescu, Maria Nicoleta Grecu, Nicolae Stanica, Mariana Carmen Chifiriuc, and Rodica Olar

performed by the micro-titre method, following previously described protocols [ 21 ]. The absorbance at 490 nm was measured with an ELISA reader Apollo LB 911. All biological experiments were performed in triplicates. Synthesis and

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