JOURNAL OF NUCLEAR SCIENCE AND TECHNOLOGY
Year:2005 | Volume:- | Issue:1 (33)|Papers Count:8

Batch experiments were conducted to study the ability of marine algae collected from Oman Gulf, Iran, for sorption of cobalt from the metal nitrate solution. The biosorption experiments were performed using native and chemically pretreated sun-driedbiomass of marine algae. Our finding indicated that MgCl2 pretreated Cystoseria indica, Sargassum glaucescens and Padina australis had more sorption capacities, while the CaCl2 pretreated ones showed lower capacity (comparing with non-treated native biomass). Also, a fall in the cobalt uptake capacity of Nizimuddinia zanardini, Gracilaria corticata, G. arcllata, Botryocladia leptopoda, Scinaia camosa, Hypnea valentiae, VIvafasciata and Codium sp. took place after treatment with chemicals, including CaCl2 (0.1 M), MgCl2 (0.1 M), Ca Cl2 (0.1 M)/HCl (pH 2) and HCl (0.1 M). Biosorption of cobalt Was rapidly took place onto algal biosorbents and most of the sorbed metal ion was bound in the first minutes of contact. Uptake of cobalt was pH-dependent and the most cobalt removal occurred at pH 4. In our screening investigations, brown algae (Dictyota indica, N. zanardini, P. australis, S. glaucescens, and C. indica) removed cobalt most efficiently from aqueous solution, respectively. The capability of marine algae for separationof 60Co was tested and a high 60Co removalwas demonstrated.

Cu-pymvaldehyde-bis (N4-methylthiosenricarbazone) (Cu-PTSM) is the most important copper radiopharmaceutical used in clinical experiments. In this work. Copper-61 (T1/2=3.33 h) production process was accomplished via the natZn(p,xn)61Cu.using 22MeV protons, and the cunent of 150mA, resulted in 6.33 Ci of copper-61 with the production yield of 33.3 mCi/mAh. The completing agent. PTSM. was synthesized and its structure was confirmed by the common spectroscopic methods, followed by radio labeling with 61CU-CuCl2. The final radiopharmaceutical solution underwent common quality control tests for animal injection.

Labelled organic compounds have been widely applied to solve the research problems in life, science and chemistry. The preparation of labelled compounds with carbon-14 and tritium-3 are probably more extensively and variously used in compare with any other isotopes. These isotopes emit only beta-particle. In this paper the synthesis of DL [3H] Leucine which was prepared for the first time in Iran is described. This compound is used for diagnosis of talasemi disease. The synthetic pathwayis achieved by using the condensation of methyl allyl chloride with diethyl acetamido malonate in the presence of sodium ethoxid in ethanol .In the next step of the synthesis. the latter compound was hydrogenated with 3H2(g.) over the Adams catalyst in chloroform. which was produced ethyl 2- acetamido-2- carbetoxy -4-methyl pentanoate with a yield of 100%. In final step, the resulted product was converted directly to [4.5-3H] Leucine with the specific activity 5 Ci/mmol. by reflaxing with the hydrobromic acid of 48%.

Transmutation of long-lived tission products is one of the key issues in development and utilization of nuclear power in the world. In the study underway, we are trying to replace the burnable poison in LWR by a mixture of some LLFPs. The main tission isotope products which are included in the high level waste (HLW) with the half life more than 500 years are: 79Se, 93Zr, 94Nb, 99Tc. 107Pd. 126Sn, 129I, 135CS. Our main objective is to employ such an isotope not only with long half life but also with high neutron absorption cross section and appropriate metallic properties within chemical structure. For the matter of calculations. ENDF/B6 as nuclear data library and a series of codes such as WIMS, CITATION, and ORIGEN were used. It has been shown that 99Tc could be used instead of boron in reactor.

In this work a copper chloride laser has been constructed and the effects of different parameters such as CuCl vapor pressure, buffer gas pressure, voltage and frequency on the output power and the ratio of green to yellow power at different buffer gas pressure have been measured. Thus, by optimization of these parameters and by the exact control of the copper chloride vapor pressure as a result of increasing the distance between discharge and the lasant, a maximum specific output power of 123 (watt/lit) has been achieved. Based on the previous references, the reported specific output power in this work is the highest one among all of the copper halide lasers that have been constructed up to now, where the system is operating without any additives, like hydrogen.

Estimation of the solar radiation potential in an area is one of the most basic foundations in the development of research for applying solar energy in any region. In this study, the necessary information was taken from 9 out of 21 solar radiation stations in the country within a period of 5 to 11 years. After refining the information for some innocent lays, then it was used for intended model or mode. In order to estimate the daily average of monthly radiation on the horizon level, this existing models were closely studies and among them, 3 mathematical models, namely "angstrom pries cut", "the most probable model" , and "Hybrid model" were used. The related coefficients of each model for Iran were calculated through statistical relationship by using processed data from the above mentioned stations. These mathematical models were statistically tested for Iran and from these three, the hybrids model was chosen as the best alternative. The final result of this research is 12 drawings concerning the daily solar radiation in each month, 4 drawings related to the total radiation received by the horizontal area for each season, and one drawing in relation to the total radiation received by the horizontal area during a year.

Spices are used significantly in food industries. These substances contain high microbial contamination that causes the spoilage of the products and it is also hazardous for the health of consumers. Irradiation is one of the most effective methods to decontaminate spices. In this research, the optimum dose of e-beams to reduce microbial contamination of spices is determined Samples of spices such as: turmeric, black pepper, garlic powder onion powder oregano and spice, were packaged in 10 grams, and they were irradiated at the doses of 0 - 10 kGy by 10 MeV e-beams. After irradiation, the total microbial counts were determined by the pour plating method. The bacterial contamination of different spices was between 105 to 4.7 X107 cfu/gr and the molds count was between 1.8 x 102 to 7.2 X 103 cfu/gr. The survival curve of the bacteria was drawn in terms of bioburden versus the radiation dose rates. By determining the D10 value, the minimum dose for reducing the spices microbial contamination up to the optimum limit, were identified.

External occupational reports of NRC workers are provided to health physics group by the National Protection Department. These results as preliminary data are registered to a computer program that was designed using FoxBASE and Excel software by the authors. The output data provided by this program include monthly and annual intakes dose as well as external dose of workers in each department. The results show that during 1367 to 1382, the highest value of external intake dose is on an average 1.26mSv for the Radioisotope Department and the lowest value is on an average O.48mSv for the Nuclear Biotechnology Department. Also, we have found that the workers intake the highest dose in 1371, 1372 and 1381; and the lowest value is in 1367.