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Acta Veterinaria Hungarica
Authors: Horea Šamanc, Danijela Kirovski, Nada Lakić, Irena Celeska, Slavica Bojković-Kovačević, Željko Sladojević, and Ivan Ivanov

Scaramuzzi, R. J. (2007): An analysis of the relationship between plasma urea and ammonia concentration in dairy cattle fed a consistent diet over a 100-day period. J. Dairy Res. 74, 412–416. Scaramuzzi R. J

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Abstract  

Radon can accumulate in underground areas such as show caves. Repairmen and tourist guides working in such caves may thus be exposed to significant radiation doses. Therefore, it is necessary to measure the radon concentration to estimate the exact radiation dose caused by radon. Considering that the radon concentration in caves usually shows significant seasonal fluctuations, the monthly change of radon concentration was studied for 1 year in nine show caves opened to the public in Hungary. Despite the fact that all of the caves were formed in karst rocks, the annual average radon concentration levels were rather different between each other (541–8287 Bq m−3). The significant monthly fluctuation of the radon concentration indicates that the annual average radon concentration in caves can only be accurately obtained by year-long measurements.

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Some results of the plutonium determination for bone ash samples collected in Japan are presented. Mean239,240Pu concentration in the adult vertebra was 0.53 pCi/kg of ash during the period 1978 through 1983. The data are roughly in coincidence with estimated plutonium concentrations in the trabecular bone from reported air plutonium concentrations using the ICRP model and metabolic data, and weight of bone in Reference Japanese Man.

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Activity concentrations of 40K and 3H in drinking water from four sources in the vicinity of NPP Krško and their correlation with geological data are presented. The data extends from the year 1996 until present. In addition, activity concentrations of 40K in drinking water at randomly selected sources in Slovenia are presented on a map. These activity concentrations vary by more than an order of magnitude with the largest values in northeastern part of the country.

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Seasonal variations of radionuclide concentration in pine needles (Pinus Thunbergii) were examined. The seasonal variations were classified roughly into two types, one represented by the periodical variation of137Cs concentration and the other represented by a linear decrease of103Ru concentration when plotted on a semi-log scale. Weathering half-lives for the latter type of nuclides were estimated and a fairly good consistency in the half-lives for different nuclides was observed irrelevant to their radioactive half-lives.

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Radiocesium concentrations in cow's milk from two producing districts in Japan were measured monthly for three years following the Chernobyl accident. The Chernobyl contribution in137Cs concentration was evaluated from the134Cs concentration and the137Cs/134Cs ratio. The highest137Cs concentration of 0.6 Bq l–1 was observed in May 1986 and the Chernobyl contribution has decreased during three years to levels corresponding to the contribution from past nuclear weapons fallout. Annual values of child internal dose through milk consumption were estimated at 0.6, 0.3 and 0.1 Sv for the first, the second and the third year following the accident, respectively.

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For a realistic dose estimation, we derived the concentration factors (CF) of plutonium and americium for the field measurements of marine products and ambient coastal sea water.The distribution of the concentration ratios (CR) between the concentration in marine products and that in ambient sea water shows a lognormal distribution. The concentration factors of plutonium and americium which are derived as the geometric mean of CR values, are 231 and 67 for whitebait, 12 and 37 for flatfish, 350 and 220 for brown algea, 140 and 670 for shell fish, 27 and 130 for cephalopods, and 250 and 550 for crustaceans, respectively.

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This paper presents radon and thoron concentrations measured in the prehispanic tunnel of the Sun Pyramid and in the archeological tunnel 1 in the Moon Pyramid. Radon and thoron concentrations were measured using several electret passive environmental radon monitor (E-PERM) configurations and detection systems. Results were in good agreement with no significant difference (P<0.01). Radon concentration in both pyramids was 1ower than the action levels proposed by the ICRP 65. Therefore, the equivalent effective dose (HE) calculated for the highest concentration was much lower than the action level (3-10 mSv . y-1). A quality assurance program was improved.

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Abstract  

Relative concentration theory studies the degree of inequality between two vectors (a1,...,aN) and (α1,...,αN). It extends concentration theory in the sense that, in the latter theory, one of the above vectors is (1/N,...,1/N) (N coordinates). When studying relative concentration one can consider the vectors (a1,...,aN) and (α1,...,αN) as interchangeable (equivalent) or not. In the former case this means that the relative concentration of (a1,...,aN) versus (α1,...,αN) is the same as the relative concentration of (α1,...,αN) versus (a1,...,aN). We deal here with a symmetric theory of relative concentration. In the other case one wants to consider (a1,...,aN) as having a different role as (α1,...,αN) and hence the results can be different when interchanging the vectors. This leads to an asymmetric theory of relative concentration. In this paper we elaborate both models. As they extend concentration theory, both models use the Lorenz order and Lorenz curves. For each theory we present good measures of relative concentration and give applications of each model.

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Since the early days of mankind, plants have been used as food and for medicinal purposes. Still, little information exists in literature about the activity concentration of 238U and 232Th decay products, as well as stable element concentrations in Brazilian plants. Activity concentrations of 226Ra, 228Ra and 210Pb, and chemical concentrations of As, Ba, Br, Cs, Co, Cr, Cu, Eu, Fe, Hf, La, Lu, Rb, Sb, Sc, Sm, Ta, Tb, Yb, Zn and Zr were determined in ten samples commonly used in Brazilian medicinal plants.

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