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Abstract  

In order to explore the influence of CeO2 on the structure and surface characteristics of molybdena, an investigation was undertaken by using N2 adsorption (BET method), thermal analysis and in-situ diffuse reflectance infrared (DRIFT) techniques. In this work, the Mo/CeO2 and Ce-Mo/Al2O3 samples were prepared by impregnation and co-precipitation methods with high Mo loadings. Combining the results one may notice that the presence of ceria led to the increase of polymerized surface Mo species so as to forming Mo-O-Ce linkages besides the formation of coupled O=Mo=O bonds indicative of polymeric MoO3. From thermal analysis, it can be inferred that Mo/Al2O3 is the thermally most stable material in the temperature range used in the experiment (up to 900°C), whereas Ce-Mo/Al2O3 and Mo/CeO2 samples undergo morphological modifications above 700°C resulting in lattice defects, which motivate the mobility of Mo and Ce ions and thus enhance the possibility of interaction between them. Additionally, their activity towards CO adsorption needs reduced ceria and molybdena containing coordinatively unsaturated sites (CUS), oxygen vacancies and hydroxyl groups to form various carbonate species.

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Abstract  

It is suggested to spend some time in a cave for curing respiratory diseases. Some ascribe the healing effect partly to radon. In Hungary in the Hospital Cave of Tapolca the mean radon concentration shows 17 times difference in the winter and in the summer period. The change of the forced exhaled volume in 1 s (FEV1) values was examined measured by 1824 patients in this cave. By 70% of the patients the FEV1 value improved, by 30% it became worse but these were independent from the radon concentration of the cave. Therefore, radon concentration has no positive effect during the treatments performed in Tapolca.

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Efforts have been made to predict the sensory profile of coffee samples by instrumental measurement results. The objective of the work was to evaluate the most important sensory attributes of coffee samples prepared from ground roasted coffee by electronic tongue and by sensory panel. Further aim was to predict the Arabica concentration and the main sensory attributes of the different coffee blends by electronic tongue and to analyze the sensitivity of the electronic tongue to the detection of poor quality coffee samples. Five coffee blends with known Arabica and Robusta concentration ratio, five commercially available coffee blends and a poor quality coffee were analyzed. The electronic tongue distinguished the coffee samples according to the Arabica and Robusta content. The sensory panel was able to discriminate the samples based on global aroma, bitterness and coffee aroma intensity (p < 0.01). The Arabica concentration was predicted from the electronic tongue results by PLS with close correlation and low prediction error. Models were developed to predict sensory attributes of the tested coffee samples from the results obtained by the electronic instrument.

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Abstract  

The radiation dose of workers and patients resulting from inhaling radon and through the consumption of spring waters was examined in the hospital near the Héviz lake in Hungary. The radiation dose originating from radon was 2.15–3.95 mSv·y−1 concerning workers at the spa. The radiation dose originating from radon in the case of those regularly taking a bath was an average of 0.75 mSv·y−1. Due to the limited duration of treatments a bound effective dose of maximum 100 µSv·y−1 may originate from radon and inhaling radon, while a maximum of 1.4 µSv·y−1 may originate from ingestion of 222Rn, 226Ra, 234U and 238U radionuclides.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
J. Somlai
,
G. Szeiler
,
P. Szabó
,
A. Várhegyi
,
S. Tokonami
,
T. Ishikawa
,
A. Sorimachi
,
S. Yoshinaga
, and
T. Kovács

Abstract  

In the last few decades attention has been given to improve workplace conditions, primarily to reduce the different health risks. In the air that accumulates in underground workplaces radon may constitute one of the health risks. The radon concentration in the show cave in Tapolca is especially high in summer months, with the annual average in the year 2005 being 7227 Bq/m3, in 2006 8591 Bq/m3. The radon concentration was found to be independent on the location of the measurement. Its value was rather similar for working hours and for the total period. The hours spent in the cave by the workers depend on the number of visitors. The radiation dose, estimated on the basis of personal dosimeters, is significant for those working there especially, employed during the whole year. Taking into consideration the actual working hours and the equilibrium factor, F = 0.4, given in the literature, it approaches and even exceeds the dose limit of 20 mSv/year. With a well organized work schedule, as well as the employment of outside workers during the summer period, the dose limit of 20 mSv/year can probably be maintained. However, on the basis of recent measurements, the actual equilibrium factor was determined to be F = 0.5, which in turn means a further 25% increase in the dose effect.

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Progress in Agricultural Engineering Sciences
Authors:
V. Parrag
,
Z. Gillay
,
Z. Kovács
,
A. Zitek
,
K. Böhm
,
B. Hinterstoisser
,
R. Krska
,
M. Sulyok
,
J. Felföldi
,
F. Firtha
, and
L. Baranyai

Abstract

One of the most important food safety issues is the detection of mycotoxins, the ubiquitous, natural contaminants in cereals. Hyperspectral imaging (HSI) is a new method in food science, it can be used to predict non-destructively the changes in composition and distribution of compounds. That is why, in the last decade, the potential of HSI has been evaluated in many fields of food science, including mycotoxin research.

The aim of the recent study was to test the feasibility of HSI for the differentiation according to the toxin content of cornmeal samples inoculated with Fusarium graminearum, Fusarium verticillioides and Fusarium culmorum and samples with natural levels of mycotoxins. Samples were measured in the near infrared wavelength range of 900–1,700 nm and mean spectra of selected regions of interest of each image were pre-treated using Savitzky-Golay smoothing and standard normal variate (SNV) method. On the spectra, partial least squares discriminant analysis (PLS-DA) was carried out according to the level of contamination. Partial least squares regression (PLSR) method was used to predict deoxynivalenol (DON) content of samples and the cumulative toxin content: the sum of fumonisins (FB1, FB2) and DON content of samples. Based on the promising results of the study, HSI has the potential to be used as a preliminary testing method for mycotoxin content in feed materials.

Open access
Progress in Agricultural Engineering Sciences
Authors:
K. Szalay
,
B. Keller
,
R. Rák
,
N. Péterfalvi
,
L. Kovács
,
J. Souček
,
F. Sillinger
, and
A. Jung

Abstract

One of the biggest challenges of raspberry production in Hungary nowadays is reducing the unfavorable effects of climate change. The maturation phase of main varieties within this region falls in a period of extremely high temperature and atmospheric drought detaining desirable fruit growth. Dedicated plant breeding alone is not enough. An immediate action is required. There has been a need for physical protection against excessive direct radiation. In order to restore, or even save the domestic raspberry production and market, introducing of greenhouse or polytunnel solutions are needed. Experimental plantations of three different raspberry varieties were set in two repetitions: covered and uncovered versions. Each cover has characteristic interaction with light which can generate different environmental conditions and also differences in plant growth and fruit quality. Besides the monitoring of elementary biological indicators, a wide range of sensors (temperature, humidity, solar irradiation) was used to identify differences and to find the optimal tunnel material for maximal plant productivity. Within the framework of the project we also tested a portable spectroradiometer and a snapshot imaging camera to study the practical value of proximal sensing in water- and photosynthetic light use efficiency and vitality mapping.

Open access
Journal of Radioanalytical and Nuclear Chemistry
Authors:
A. Türler
,
H. Gäggeler
,
K. Gregorich
,
H. Barth
,
W. Brüchle
,
K. Czerwinski
,
M. Gober
,
N. Hannink
,
R. Henderson
,
D. Hoffman
,
D. Jost
,
C. Kacher
,
B. Kadkhodayan
,
J. Kovacs
,
J. Kratz
,
S. Kreek
,
D. Lee
,
J. Leyba
,
M. Nurmia
,
M. Schädel
,
U. Scherer
,
Schimpf
,
D. Vermeulen
,
A. Weber
,
H. Zimmermann
, and
I. Zvara

Abstract  

On-line isothermal gas phase chromatography was used to study halides of261104 (T1/2=65 s) and262,263105 (T1/2=34 s and 27 s) produced an atom-at-a time via the reactions248Cm(18O, 5n) and249Bk(18O, 5n, 4n), respectively. Using HBr and HCl gas as halogenating agents, we were able to produce volatile bromides and chlorides of the above mentioned elements and study their behavior compared to their lighter homologs in Groups 4 or 5 of the periodic table. Element 104 formed more volatile bromide than its homolog Hf. In contrast, element 105 bromides were found to be less volatile than the bromides of the group 5 elements Nb and Ta. Both 104 and Hf chlorides were observed to be more volatile than their respective bromides.

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