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- Author or Editor: S. Baba x
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Abstract
The relative gamma-ray intensities in the energy region between 122 and 411 keV in the decay of152Eu were measured by using a Ge(Li) detector. Its efficiency calibration was carried out with the radioactive sources of241Am,57Co,203Hg,137Cs,133Ba,75Se,169Yb and192Ir.
Pumpkin, squash and zucchini are important vegetable crops in tropical and temperate regions. The development of genetic transformation methods offers the potential of introducing valuable traits into these crops. An efficient in vitro plant regeneration system is a critical point for genetic manipulation. The regeneration ability of three Cucurbita varieties was tested on Murashige and Skoog medium supplemented with different growth regulators. Cotyledons of all the varieties were cultured to investigate the effect of 2,4-D (0, 1, 2, 3, 4 mg l −1 ) with or without KIN (0, 0.5, 5 mg l −1 ) and of BA (0, 1, 1.2 mg l −1 ) combined with IAA (0, 0.9, 1, 1.2 mg l −1 ), on the efficiency of shoot induction. Abscisic acid (0.26 mg l −1 ABA) was also added to one medium. To find the most suitable combination for shoot induction, cotyledon segments of the three varieties were also cultivated on media with different concentrations of BA (0–1.2 mg l −1 ) and IAA (0–0.9 mg l −1 ). Shoot induction was achieved via organogenesis in the tested varieties. Leafy shoots were transferred to root induction media. Regenerated plantlets with roots were transferred to sterile soil. This is the first report on in vitro regeneration from cotyledon explants of the pumpkin cultivar Nagydobosi and the pattypan squash cultivar Óvári fehér.
Abstract
Activity concentrations of radionuclides,7Be,210Pb and210Po, in precipitation (rain, throughfall and stemflow), wood and soil were determined by using gamma-ray and alpha-ray spectrometry to estimate the migration behavior of these radionuclides in the forest canopy. The activity ratios between output and input precipitations for the forest canopy were 0.53 of7Be, 0.79 of210Pb and 1.5 of210Po for Pasania edulis forest. A dynamic model of the transport and fate of radionuclides in the forest ecosystem was constructed. Mean residence times of radionuclides were 56 days for7Be, 765 days for210Pb and 653 days for210Po for Pasania edulis forest.
Abstract
Activation data of lead are of great importance due to the widespread applications of this element in various technological fields and to the well known adverse effects to biological systems. Use of high sensitivity radioanalytical techniques allows study of uptake, distribution and speciation. Cross sections of deuteron induced nuclear reactions on lead were measured up to 40 MeV using the standard stacked foil irradiation technique and high resolution gamma-ray spectrometry. Experimental cross sections and derived integral yields are reported for the natPb(d,xn)203,204,205,206,207Bi, natPb(d,x)203Pb202Tl reactions. Only one set of experimental cross section data was found in the literature. The experimental data are analyzed and compared with the results of the theoretical model code ALICE-IPPE and with the experimental integral yield reported in the literature.
Abstract
The solvent extraction behavior of radioioine and astatine has been investigated under various conditions in order to compare the extraction behavior of astatine with radioiodine at tracer concentration. In this study, basic tracer solutions of astatine and radioiodine were extracted into the CS2 solution under various conditions. Astatine existed as a pure species in the tracer solution and formed cationic compound in the acidic solution which was also extracted into the organic solvent instantaneously. On the other hand, radioiodine existed as a complex in the tracer solution and was partly extracted into the organic solvent at tracer concentration. The observed different extraction behavior of astatine and radioiodine were consistently explained by the respective proposed extraction reaction schemes.
Abstract
A scheme for the sequential separation of fission products has been developed on the basis of ion-exchange techniques. It consists of a main cation-exchange process for group separation and subsidiary processes of cation or anion exchange for further separations or purifications of the individual fission products. By the present method, Zn, Rb, Sr, Y, (Zr), Mo, Pd, Cd, Te, Cs, Ba, La, Ce, Pr, Nd, Pm, Sm, Eu and Tb can be separated simultaneously from an irradiated uranium sample. Of these, alkali, alkaline earth and rare earth metal ions are separated quantitatively. A polarographic method was applied to determine the recoveries of Zn, Mo, Pd, Cd and Te, which were not separated quantitatively.
Abstract
Interest in organic growing systems that means no harm to the environment, mankind, and the world’s natural ecosystem is increasing. This study evaluated the impact of organic versus conventional cultivation method on eggplants (Topan-374 and Pala-49), tomatoes (Rio Grande and Pink), and bell pepper (Kandil dolma) considering individual phenols, total phenol-flavonoid content, antioxidant capacity, and antibacterial potential. Peel and pulp of eggplants were evaluated separately. Organic cultivation enhanced trans-ferulic acid in the peels of both eggplant cultivars and the pulp of Pala-49. Organic Pala-49 had also higher amounts of cyanidin and caffeic acid in the peel, and only caffeic acid in the pulp. Chlorogenic acid was found in higher quantities in organic Rio Grande tomato and bell pepper. All organically grown vegetables in our study had significantly higher total phenol and flavonoid contents than conventional ones except Pink tomato. Organic farming significantly enhanced the antioxidant capacity of both eggplant cultivars. Only organic peel of Pala-49 eggplant cultivar had antibacterial activity against Staphylococcus epidermidis. Organic cultivation has an advantage in terms of antioxidant potential and phenolic constituents, and it enhanced the nutraceutical potential of both cultivars of eggplant, Rio Grande tomato, and bell pepper.
Abstract
Target-like products, that is,191–200Au,185–200Pt, and183–195Ir, from197Au target bombarded with12C ions at the energies of 180, 230, and 400 MeV/u were measured by using off-line gamma-ray spectrometry combined with chemical separation procedures. Spallation systematics by Rudstam reproduces well the measured cross sections for formation of platinum and iridium isotopes. It was found that the cross sections of gold nuclides increase with increase of the incident energy in the range studied and they are enhanced if compared with the reported proton-induced reaction of gold at a similar incident energy. It is suggested that the electromagnetic dissociation process plays a role for production of such gold nuclides.
Abstract
Excitation functions of proton induced reactions on Pd are important for medical radioisotope production, for activation analysis, for development of low activation materials and other purposes. No experimental data exist in the literature for low and medium energy range protons. A detailed study of the excitation functions was performed up to 80 MeV proton energy by using the stacked foil irradiation technique and gamma-ray spectrometry. The irradiations were carried out at the external beam lines of the AVF cyclotron at the Tohoku University. Japan (80 and 70 MeV) and the CGR 560 cyclotron at the Vrije Universiteit Brussels (38, 29 and 17 MeV). The beam intensity, the incident energy and the energy degradation were controlled by a method based on flux constancy via normalization to the parallel measured excitation functions of natAl(p,x)22,24Na and natCu(p,x)56,58Co, 62,65Zn monitor reactions. Excitation functions for direct and cumulative cross sections have been measured for the production of 105mg,106m,110mAg, 101Pd, 101mRh and 97Ru radionuclei. Calculations for the excitation functions using the Alice-IPPE code were performed with a view to estimate the weight of the different contributing reactions and to check the trend and the magnitude of the obtained experimental data.
Abstract
Annihilation γ-rays of π0 and pionic X-rays were measured in the gas mixtures of H2+Z and CH4+Z systems (Z=He, Ne, Ar and Kr). Pion capture probability of hydrogen atom was obtained from the annihilation γ-ray counts and the capture probability of Z atom was obtained from the pionic X-ray intensities. Transfer rates were determined from the data based on a combined large mesomolecular model. The transfer rates obtained were smaller than the systematics of the Russian group. Difference in the transfer rate between the gas and the liquid phases was found by a comparison of the present results with our previous ones.
