Nuclear Science and Technology Institute

Various concentrations of copper are embedded into silica matrix to xerogels form using copper source—Cu(NO3)2·3H2O. The xerogel samples are prepared by hydrolysis and condensation of tetraethyl orthosilicate (TEOS) with determination of new molar ratio of components by the sol–gel method. CuO/SiO2 nanocomposite is prepared with mixture of components with new molar ratio of H2O/TEOS to be 6.2. In this investigation, the necessary amount of trihydrated copper nitrate is added to the solution in such a manner that the concentration of the copper oxide in final solution reaches 1, 2 and 5 wt% (samples A, B and C, respectively). After ambient drying, the gel samples are heated from 60 to 1,000 °C at a slow heating rate (50 °C/h). Thermal treatment effect is characterized by Fourier transmission infrared, thermal gravimetric analysis, X-ray diffraction, transmission electron microscopy, scanning electron microscopy, surface analysis and thermal program reduction methods at different temperatures.

The SiO2-CaCl2 hybrid porous materials were prepared by the sol-gel method. This process was conducted by the hydrolysis and condensation of Tetraethyl orthosilicate (TEOS) by replacement of ethanol from alcogel and drying at the ambient temperature to obtain xerogel structure. The alcogel samples were synthesized from TEOS, EtOH, H2O, HCl, NH4OH and CaCl2, while the total molar ratio of the compounds was 1: 9: 4: 8 x 10-4, 8 x 10-3, respectively. Xerogel containing 30 wt % of CaCl2 (dry matter) was prepared and characterized by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Furier Transmittance Infra Red spectrum (FT-IR), Energy Dispersive X-ray (EDX) and Thermal Gravimetric Analysis (TGA ) systems. The results obtained from SEM and EDX showed the micrograph of CaCl2 on the silica and chemical elemental analysis, respectively. On the other hand, The TEM micrograph confirmed average particle size of SiO2-CaCl2 about 50 nm and FT-IR spectrum described the functional groups of the nanocomposite. The thermal analysis of SiO2-CaCl2 nanocomposite was performed using TGA system and the results showed that the suitable temperature for initial thermal treatment was about 200°C.

Introduction: Trastuzumab is a monoclonal antibody that is used in treating breast cancer. We labeled this monoclonal antibody with Technetium-99m and performed in vitro and in vivo quality control tests as a first step in the production of a new radiopharmaceutical. Methods: Trastuzumab was labeled with Technetium-99m using Succinimidyl Hydrazinonicotinamide (HYNIC) as chelator. Radiochemical Purity and stability in buffer and serum were determined. Immunoreactivity and toxicity of the complex were tested on SKBR3, MCF7 and A431 breast cancer cell lines. Biodistribution study was performed in normal mice at 4 and 24 h post injection. Results: The radiochemical purity of the complex was 95±1.4%. The stabilities in phosphate buffer and in human blood serum at 24 h post preparation were 85±3.5% and 74±1.2%, respectively. The immunoreactivity of the complex was 86±1.4%. The binding of labeled antibody to the surface of SKBR3, MCF7 and A431 cells were increased by increasing Her2 concentration on the cells surface. Conclusions: The findings showed that the new radiopharmaceutical can be a promising candidate as Her2 antigen scanning for human breast cancer.

In this work, radiological assessment of atmospheric release from Tehran’s Research Reactor (TRR) stack and assessment of public exposures under normal operation has been studied. To perform tasks mentioned above, Pc-Cream computer code which simulates Gaussian Dispersion air transport plume model as well as laboratory analysis of the soil and leaves samples and TLD (Thermo Luminescent Dosimeter) monitoring around the TRR site was used. Results of the Pc-Cream code showed that the annual committed and external dose received by the individual in the vicinity of the reactor is below the regulatory limit. Also, the results of laboratory analysis of available radionuclides in the soil and leaves samples showed that the concentrations are close to the background (K40=635, Th232=28, Cs137=0.29 up to 28.82, Ra226=25 (Bq[1]/Kg) in soil and K40=457, Be7≈70 (Bq/Kg) in leaves) and confirm the code results. The monitored dose values of the TLD detectors were positioned around the reactor within 500 m radius shows that the background dose in vicinity of TRR (113 μSv up to 150 μSv) is consistent with the background dose in Tehran province (125 μSv).

BACKGROUND: Most of the neuroendocrine tumors (NETs) express Somatostatin receptors (SSTr), which are the main bases for the development of several radiopharmaceuticals for therapy and imaging of these types of tumors. In this study, 46 Scandium nuclide was used to label a peptide compound via hydrazinonicotinyl-Tyr3-Octreotide (HYNIC-TOC) and researched further for somatostatin-receptor NETs treatment. METHODS AND MATERIALS: The labeling procedure was conducted at 95°C for 10 min. The compound stability was tested in the environment of human serum at 37°C. The biodistribution of compound was investigated in balb/c normal mice and mice bearing AR4-2J tumor. Absorbed Doses of Human Organs were estimated by extrapolation of the biokinetics data of compound in mice to human's organs and then the absorbed doses were estimated by application of MATLAB and MIRDOSE software. RESULTS: Labeling yield was more than 90% with 555 MBq/mg specific activity. The radio-labeled compound expressed well consistency in human serum. The tumor uptake reached 3.831 ID/g% until 4 h post-injection and increased to 5.564%ID/g until 24 h post-injection. CONCLUSION: The main achievement of this study was high tumor uptake of 46 Sc-HYNIC-TOC which may be therapeutically valuable for the therapy of NETs. The estimation of the absorbed dose of human from 47 Scandium-HYNIC-TOC showed low absorbed doses in critical organs and the elimination of the radiopharmaceutical was through the gastrointestinal tract.

Based on visual observation and digital images,two-phase flow patterns in smooth glass tubes under rolling condition were identified.In the paper,effects of tube size,rolling angle and rolling period on the transition between different flow patterns were analyzed in detail.The results showed that with the same superficial liquid velocity,(increased) tube size,shortened rolling period or decreased rolling angle could make annular flow beginning need higher than superficial gas velocity,and the transition from slug flow to churn flow also need more gas flow rate when tube size and rolling angle decreased,or rolling period increased.Besides,when the superficial gas velocity kept constant and tube size increased,rolling period shortened or rolling angle increased,the transition from slug flow to bubble flow requires more liquid flow rate.

<strong>Introduction:</strong> Trastuzumab is a monoclonal antibody that is used in treating breast cancer. We labeled this monoclonal antibody with Technetium-99m and performed in vitro and in vivo quality control tests as a first step in the production of a new radiopharmaceutical. <strong></strong> <strong>Methods:</strong> Trastuzumab was labeled with Technetium-99m using Succinimidyl Hydrazinonicotinamide (HYNIC) as chelator. Radiochemical Purity and stability in buffer and serum were determined. Immunoreactivity and toxicity of the complex were tested on SKBR3, MCF7 and A431 breast cancer cell lines. Biodistribution study was performed in normal mice at 4 and 24 h post injection. <strong>Results:</strong> The radiochemical purity of the complex was 95±1.4%. The stabilities in phosphate buffer and in human blood serum at 24 h post preparation were 85±3.5% and 74±1.2%, respectively. The immunoreactivity of the complex was 86±1.4%. The binding of labeled antibody to the surface of SKBR3, MCF7 and A431 cells were increased by increasing Her2 concentration on the cells surface. <strong>Conclusions:</strong> The findings showed that the new radiopharmaceutical can be a promising candidate as Her2 antigen scanning for human breast cancer.

Experimental studies on the upward gas-liquid two phase flow under rolling and steady state were carried out respectively.It found that when the volumetric flow rate of water was lesser,the void fraction was lesser under rolling state than under steady state,which was explained reasonably through observing experimental phenomena and analyzing friction coefficient of single-liquid phase under two states.

In this work, radiological assessment of atmospheric release from Tehran’s Research Reactor (TRR) stack and assessment of public exposures under normal operation has been studied. To perform tasks mentioned above, Pc-Cream computer code which simulates Gaussian Dispersion air transport plume model as well as laboratory analysis of the soil and leaves samples and TLD (Thermo Luminescent Dosimeter) monitoring around the TRR site was used. Results of the Pc-Cream code showed that the annual committed and external dose received by the individual in the vicinity of the reactor is below the regulatory limit. Also, the results of laboratory analysis of available radionuclides in the soil and leaves samples showed that the concentrations are close to the background (K40=635, Th232=28, Cs137=0.29 up to 28.82, Ra226=25 (Bq[1]/Kg) in soil and K40=457, Be7≈70 (Bq/Kg) in leaves) and confirm the code results. The monitored dose values of the TLD detectors were positioned around the reactor within 500 m radius shows that the background dose in vicinity of TRR (113 μSv up to 150 μSv) is consistent with the background dose in Tehran province (125 μSv).

In this paper, increase in laser induced damage threshold (LIDT) of Nd:YAG crystal by XeCl and ArF laser irradiation is reported. Differential absorption spectra of the crystal samples show that oxygen vacancy defects can be annihilated by low dose excimer laser irradiation. 30 ns linearly polarized, 1064 nm single longitudinal mode,TEM00 laser pulses of a Q switched oscillator-amplifier system was used for LIDT measurement. LIDT of the irradiated crystals was obtained about three to five times higher than the LIDT of the un-irradiated crystal. Our results are very important in high power laser system applications.

Feathers are a waste product generated in large quantities from commercial poultry processing. Recycling of feathers is an interesting subject among animal nutritionists, because of its potential as a cheap and alternative protein feedstuff. Although feathers are deficient in certain essential amino acids such as methionine, lysine, histidine and tryptophan, they contain other amino acids such as arginine, and threonine (Onifade et al., 1998). Feather waste has been used as feedstuff for poultry and livestock. Without appropriate processing, feather meal has little nutritive value because keratin is not degraded by most proteolytic enzymes. The proteolytic resistance of keratin results from its structural features tight packing of protein chains, hydrogen bonding among polypeptides, and hydrophobic interaction and stabilization of the super-coiled polypeptide chains (Onifade et al., 1998). Many treatments have been developed to increase the digestibility of feather meal and are usually categorized into two groups: hydrothermal treatments and microbial keratinolysis (Onifade et al., 1998). Food irradiation has been recognized as a reliable and safe method for preservation, improve hygienic quality and improve the nutritional value of foods (Diehl, 2002). Lee (1962) observed that sulfhydryl and disulphide groups in proteins are apparently highly susceptible to irradiation and destruction of disulphide bonds improves digestibility of proteins.