Authors:E. Kuzmann, M. Varsányi, L. Korecz, A. Vértes, T. Masumoto, F. Deák, Á. Kiss, and L. Kiss
Neutron, and Mössbauer spectroscopy were used to study the possibility of cold nuclear fusion in Fe90Zr10 amorphous ribbon having high hydrogen absorbing ability. No significant changes in the neutron and in the spectra were found at deuterization performed electrochemically at different cathodic potentials. The observed differences between the Mössbauer spectra of samples deuterized in air and in nitrogen atmosphere can be explained by decrease of deuterium uptake as well as by a small heat effect due to reaction of hydrogen with oxygen dissolved in water in the case of electrolysis carried out in air.
Authors:K. Papp, É. Kocsárdy, A. Kiss, and T. Lakatos
The effect of reduction of pressure on the shapes of the TG, DTG and DTA curves and the mass-spectra of hydroxide and carbonate phases was investigated in some typical Hungarian red muds. The pressure change caused different decomposition rates of the phases and resulted in better separation of the overlapping thermal curves; this led to advantages as regards phase analysis. For phase analysis the red muds were extracted with water, and the extracts and solid residues were identified by IR- and X-ray methods.
Authors:R. Marinkovic-Neducin, E. Kiss, T. Cukic, and D. Obadovic
The purified bentonite parent clay, fraction ≤; 2 mm of montmorillonite type, has been pillared by various polyhydroxy cations,
Al, AlFe and AlCu, using conventional pillaring methods. The thermal behavior of PILCs was investigated by combination of
X-ray diffraction (XRD), thermal analysis (DTA, TG) and low temperature N2 adsorption/desorption (LTNA). Thermal stability
of Al-, AlFe- and AlCu-PILC samples was estimated after isothermal pretreatment in static air on the temperatures 300, 500,
600 and 900C. Crucial structural changes were not registered up to 600C, but the fine changes in interlayer surrounding
and porous/microporous structure being obvious at lower temperatures, depending on the nature of the second pillaring ion.
AlFe-PILC showed higher thermal stability of the texture, the AlCu-PILC having lower values and lower thermal stability concerning
both overall texture and micropore surface and volume. Poorer thermal stability of AlCu-PILC sample at higher temperatures
was confirmed, the presence of Cu in the system contributing to complete destruction of aluminum silicate structure, by 'extracting'
aluminum in stabile spinel form.
Authors:Éva Lehoczky, T. Németh, Zs. Kiss, and et al.
The pot experiment - carried out in 2000 under greenhouse conditions -
was set up with seven soils differing in Cd and Pb contents and three test
L. cv. Georgikon), lettuce (
L. cv. Balatonzöld) and white mustard (
L. cv. Sirola) with
four replicates. From the seven experimental soils five samples (S1-S5) were
collected from agricultural areas (arable sites) and two (S6-S7) from
spoil-earth, with extremely high Cd and Pb contents. The pots, each containing 1 kg air-dry soil,
were kept at constant soil moisture (60% of maximum water capacity of the
experimental soils) by daily watering, while pots were watered to weight once
weekly. Before sowing the test plants: 50-50-50 mg N, P
O was applied to the experimental soils to maintain the same
nutrient supply. The above-soil plant parts were cut after four weeks. Fresh
and dry weights of plants were determined after harvest.
The aim of the
experiment was to obtain results of Cd and Pb uptake by different plant species
in relation to the heavy metal content and different characteristics of soils. The following conclusions were drawn:
correlation was found between the biomass production of the three test plants
and the heavy metal content of the soils at early growth stage. The heavy metal
concentration range in the soils and plants differed. In the case of Pb the
soil concentration interval was broader than that of the plants'. The opposite
was observed for Cd, where the plants had a wider concentration interval.
Comparing the Pb and Cd concentrations of above-ground plant parts, Pb
concentrations varied in a narrower interval. The maximum values of Pb content
exceeded the Cd content levels, although the mobility of Pb in the soil-plant
system is significantly lower. The comparison of Cd and Pb concentrations of
plants and soils proved these differences. The Cd concentration of plants was
8-231% of the total Cd content of soils. The Pb concentration of plants was the
0.8-28% of the total Pb content of the soils, respectively. Comparing the three
plants in respect of Cd concentrations the order found was as follows: ryegrass
< white mustard < lettuce. In case of Pb, the order depended on the Pb
content level (lower or higher) of the experimental soil. Symptoms of
phytotoxicity were observed only on lettuce plants grown on the contaminated
soils (S6, S7).
Authors:G. Molnár, T. Belgya, L. Dabolczi, B. Fazekas, Zs. Révay, Á. Veres, I. Bikit, Z. Kiss, and J. Östör
Prompt gamma-activation analysis (PGAA) is an important complementary technique to conventional instrumental activation analysis that can be successfully used in a number of cases when INAA is not applicable. Therefore, a PGAA facility has been constructed at the recently refurbished and upgraded Budapest Research Reactor. It occupies the end position of a new curved themal guide of 30 m length and 2.5×10 cm2 cross section which provides a clean beam of low energy neutrons. The sophisticated HPGe-BGO -ray spectrometer system can be operated in Compton-suppression and pair-spectrometer modes simultaneously. The octal splitting of the main BGO improves efficient pair mode operation when coincidences between pairs of opposite segments and the HPGe detector are required separately. Gamma-gamma coincidence measurements will also be possible when the new multiparameter data acquisition system is completed. One of the main tasks at the new facility will be the accumulation of new spectroscopic data for detector calibration and standardisation, as well as for the construction of a more accurate prompt -ray library for the chemical elements. Various applications are planned, such as the determination of hydrogen in fullerenes and of toxic trace elements in environmental samples.
Authors:J. Németh, B. Jakab, R. Józsa, T. Hollósy, A. Tamás, A. Lubics, I. Lengvári, P. Kiss, Zs. Oberritter, B. Horváth, Z. Szilvássy, and D. Reglődi
Pituitary adenylate cyclase activating polypeptide (PACAP) is a widely distributed neuropeptide that has two molecular forms
with 38 and 27 amino acid residues. The aim of the present study was to develop a new, highly specific PACAP-27 assay to investigate
the quantitative distribution of PACAP-27 in the central nervous system of various vertebrate species applying the same technical
and experimental conditions. Our results show that the antiserum used turned to be PACAP-27 specific. The average ID50 value was 51.5±3.6 fmol/ml and the detection limit was 2 fmol/ml. PACAP-27 immunoreactivity was present in the examined brain
areas, with highest concentration in the rat diencephalon and telencephalon. Swine and pigeon brain also contained significant
amount of PACAP-27. Our results confirm the previously described data showing that PACAP-38 is the dominant form of PACAP
in vertebrates, since PACAP-38 levels exceeded those of PACAP-27 in all examined brain areas. Furthermore, our study describes
for the first time, the comparative quantitative distribution of PACAP-27 and-38 in the swine and pigeon brain.