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Abstract  

Airborne particulate matter has been collected by a high volume and a Gent-type stacked filter unit (SFU) low volume sampler during the 2000-2001 period. The high volume sampler used S&S cellulosic and the SFU two Nuclepore polycarbonate filters to collect fine and coarse size fractions. The elemental analysis of the collected TSP, fine and coarse particles has been performed using instrumental neutron activation analysis and atomic absorption spectrometry. Twenty-two trace elements on Nuclepore and twenty-four elements on S&S filters have been measured. The collected data have been compared with the previous data of Tehran air and with other cities in the world.

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Abstract  

Flameless atomic absorption techniques were used to determine the lead and other atmospheric particulate in the city of Tehran. 640 samples were collected in 20 different stations around the city during four seasons in 1992. The radioactivity of the air samples was also measured by -ray spectrometry using high purity Ge/Li detectors, and a multichannel analyzer. The results were compared with previous measurements in the city of Tehran.

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Name: Farhad Gharagheizi Date and place of Birth: 31 December 1979 Tehran-Iran Workplace: Saman Energy Giti Co., Postal Code: 3331619636, Tehran, Iran. Office address: Postal Code

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Abstract  

In this research, for the first time Nb and Ge were doped into titanosilicate nanoparticles up to 25% simultaneously. Crystalline phases and morphology of the synthesized samples were studied by X-ray diffraction (XRD) method and scanning electron microscope (SEM), respectively. Elemental analysis of the samples was performed using X-ray fluorescence (XRF) and Energy dispersive X-ray (EDX) techniques. Surface area of the samples was measured by BET method. Ion exchange potential of the synthesized samples for Sr2+ and Cs+ and effective parameters such as concentration, temperature, time, and pH were investigated. In addition,137Cs and 90Sr radio nuclides absorption in the best appropriate sample was examined. The selectivity of the samples for absorption of 137Cs and 90Sr was studied by gamma spectroscopy, liquid scintillation spectrometry, and atomic absorption spectroscopy methods. The obtained results showed that the prepared samples had good potential for absorption of 137Cs and 90Sr from the model solution. The sample containing equal amount of niobium and germanium, removed completely the 137Cs within the waste water of Tehran nuclear reactor and 90Sr in the desired solution.

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Abstract  

198Au (βmax = 0.96 MeV (98.6 %), γmax = 0.412 MeV (95.5 %) and T 1/2 = 2.7 days) is a radionuclide with very appealing characteristics. 198Au has been widely used to treat the uterus, bladder, cervix, prostate, melanoma, breast, skin and other cancers. In the present study, cationic 198Au+3 and nonionic 198Au0 are prepared following thermal neutron irradiation of commercially available natural gold compounds in Tehran Research Reactor via the natAu(n,γ)198Au reaction. The prospects in the production of pure 198Au0 and 198Au+3 for radionuclide therapy are discussed and effect of reduction on the activity of radioactive gold is evaluated. Au0 particles were synthesized via NaBH4 reduction of aqueous solutions of hydrogen tetrachloroaurate trihydrate. Then two quartz tubes were charged with cationic 198Au3+ and nonionic 198Au0. After irradiation by thermal neutrons, the samples were analyzed for a period of 1 month by liquid scintillation counter and high purity germanium detector. As a result, natAu3+ reduction process had no significant effect on the activity of the 198Au sample. In conclusions, natural gold thermal neutron activation cross section is reasonably high for medical application.

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Abstract  

Intra-hepatic administration of radioactive glass microspheres is a treatment for patients with primary liver cancer and hepatic metastases. The purpose of this study was radionuclide purity assessment of new glass particles containing two radionuclide, 90Y as a therapeutic source and also 177Lu as a source of diagnostic gamma. For the mixed source, activity measurement using a dose calibrator cannot be used and we need new calibration methods. YAS (Yb) and YAS compositions were sol–gel derived glass particles and production of 90Y (177Lu) and 90Y particles was performed using the Tehran Research Reactor. The radionuclide purity was carried out using γ-spectrometry with HPGe detector. A non-destructive spectroscopic assay was employed due to a newly updated low uncertainty positron branching ratio of 90Y that emit 511 keV annihilation radiations. In another method, a new calibration of 90Y using a non-destructive spectroscopic assay of 88Y were investigated. Potential radionuclide impurity include: 88Y, 152Eu, 60Co with activity 100, 50 and 5 Bq per 1 mg of that are not harmful for patients due to delivering radioactive particles about 20–50 mg in 90Y(177Lu) glass microspheres. Among of radionuclide impurity, 152Er with a half life of 13.54 years and 88Y with a half life of 106.65 days was important in the residual delivery device. For calibration of 90Y with monitoring of 511 keV, errors were12.2–21%. In calibration of 90Y using gamma spectroscopic assay of 88Y, there was an error less than 14%. Spectroscopic assay of 88Y can be performed easily and has more repeat for our purpose.

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JPC - Journal of Planar Chromatography - Modern TLC
Authors: Djavanshir Djozan, Ghader Karimian, Abolghasem Jouyban, Fahime Iranmanesh, Hooshangh Gorbanpour, and Ali Alizadeh-Nabil

189 193 A. Zargari , Medicinal Plants, Vol. 4, Tehran University Press, Tehran, 1993, pp. 574–578. Zargari A

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of IBU inhibition by Cu 2+ ions for this mixture was from 0.11 to 2.5 mM. Financial support from the Universities of Imam Khomeini International and Tehran is gratefully acknowledged. References

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Reagents and Standards Quercetin, methanol (HPLC grade), acetonitrile, acetone, and phosphoric acid were purchased from Merck (Darmstadt, Germany). 1-Butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]) was obtained from Kimia-Exir (Tehran

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biphenyl oxide were provided by Paksan Company (Tehran, Iran). Carbon tetrachloride, tetrachloroethylene, chloroform, chlorobenzene, acetone, acetonitrile, ethanol, and methanol were obtained from E. Merck (Darmstadt, Germany). Double distilled water was

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