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Abstract  

Stray neutron distribution in a medical cyclotron vault room was evaluated by neutron activation analysis (NAA). Neutrons were generated in the production of radioactive nuclides, such as 18F, 11C, 13N and 15O, for diagnostic usage. Indium foil was adopted to evaluate the stray fast and thermal neutron intensity based on 115In(nf, n′)115mIn and 115In(nth, γ)116m1In reactions, respectively. The indium foils were weighed, sealed and placed at 62 points around the 6.7×8.2 m2 cyclotron room. Additionally, each indium foil was exposed for over 80 minutes during cyclotron operation and γ-peaks were analyzed using an HPGe detector to evaluate the number of stray fast (Φ f) or thermal (Φ th) neutrons. The minimum to maximum numbers of fast and thermal neutrons were (3.47±0.11)×103 to (1.06±0.21)×104 n·cm−2·s−1 and 9 to 965 n·cm−2·s−1, respectively. The minimum detectable limit for stray neutrons was included herein to demonstrate the reliability. Accordingly, 60 and two points, respectively, the confidence level associated with the reported intensities of fast and thermal neutrons reached 95%. The low qualified ratio in the evaluation of stray thermal neutrons might have been caused by either the high Compton scattering plateau or the low intensity of the gamma-ray peak in the relevant spectrum.

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Abstract

There is little data on the mineralogy of carbonate pedofeatures in the calcareous soils in Hungary which belong to the European prairie ecodivision. The aim of the present study is to enrich these data.

The mineralogical composition of the carbonate pedofeatures from characteristic profiles of the calcareous soils in Hungary was studied by X-ray diffractometry, thermal analysis, SEM combined with microanalysis, and stable isotope determination.

Regarding carbonate minerals only aragonite, calcite (+ magnesian calcite) and dolomite (+proto-dolomite) were identified in carbonate grains, skeletons and pedofeatures.

The values relating, respectively, to stable isotope compositions (C13, O18) of carbonates in chernozems and in salt-affected soils were in the same range as those for recent soils (latter data reported earlier). There were no considerable differences between the values for the carbonate nodules and tubules from the same horizons, nor were there significant variations between the values of the same pedofeatures from different horizons (BC-C) of the same profile. Thus it can be assumed that there were no considerable changes in conditions of formation.

Tendencies were recognized in the changes of (i) carbonate mineral associations, (ii) the MgCO3 content of calcites, (iii) the corrected decomposition temperatures, and (iv) the activation energies of carbonate thermal decompositions among the various substance-regimes of soils.

Differences were found in substance-regimes types of soils rather than in soil types.

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Central European Geology
Authors: József Fekete, Csanád Sajgó, István Horváth, Zoltán Kárpáti, István Vetõ and Magdolna Hetényi

J. Deák 1989 Environmental isotope study ( 14 C, 13 C, 18 O, D, noble gases) on deep groundwater circulation systems in Hungary with reference to paleoclimate Radiocarbon

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enantiomers obtained in MS/MS mode The signal that appears at m/z = 206 (RI = 32.8%) refers to the appearance of the molecular ion [C 13 H 18 O 2 ] + . The moderate intensity reflects the stability of the molecular

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Acta Alimentaria
Authors: B. Šimundić, G. Krešić, A. Živkovićb and B. Medugorac

, B., Kniewald, Z. & Kniewald, J. (2003): Cytotoxic effects of organochlorine insecticides in baby hamster kidney (BHK 21 C13) cell line. Proceedings of scientific conference: Biotechnology and food. Curr. Stud. Biotechnol. , 3 , 177

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1 Lacosamide 3.85 251.1382 251.1390 −3.18 C 13 H 19 N 2 O 3 219.1119 209.1273 177.1008 144.0651 116.0704 108.0808 91.0546 74

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21 −62.28 r (Si11–C13) 1.8939 ∠H21–C8–Si7 110.85 C4–Si7–C9–H24

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MM . 2005 . Impact of Deficit Irrigation on Water Use Efficiency and Carbon Isotope Composition (Delta C-13) . of Field-Grown Grapevines under Mediterranean Climate . Journal of Experimental Botany 56 : 2163 – 2172 . [8

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940 Fisher, N. C., Nightingale, P. G., Lipkin, G. és mtsa: P/C13/32 Renal failure in long-term survivors of liver transplantation. J. Hepatol., 1997, 26 (Suppl. 1) , 152

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Journal of Thermal Analysis and Calorimetry
Authors: Adney Luís A. da Silva, Guilherme G. G. Castro and Mariana M. V. M. Souza

0.31 28.0 a = 5.4324; c = 13.3509 LSCC 0.40 33

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