Despite its beneficial effects on human life, the nuclear industry has its own risks. Strontium 90 (90Sr) is one of the most dangerous radionuclides produced by the uranium 235 fission, and replaces the bone calcium in the human body, which causes cancer. Ensuring the safety of nuclear facilities to protect employees, people and the environment is among the main goals of nuclear safety. Given close proximity of the Bushehr nuclear power plant to the Persian Gulf and the likelihood of 90Sr leaking into the marine ecosystem, this study aimed to measure this radionuclide in a sample of the bar-tail flathead fish (Platycephalus indicus) found in the Persian Gulf coastline, as people’s main source of food in the region.

Samples were taken from 10 points around the Persian Gulf coastline. The samples were analyzed using chromatographic extraction by Sr-resin and counted by the Liquid Scintillation Counter. 

The concentration of strontium 90 measured in the fish samples was 0.252- 0.955 Bq.kg-1. The mean chemical efficiency in this method was 97.34 ± 0.97 percent.

The amount of strontium 90 found in these samples was negligible and within the least detectable range. Despite the 10-year activity of Bushehr nuclear power plant, no evidence of contamination with strontium 90 was found. These results will be very useful in assessing the underlying contamination in environmental monitoring programs.

Measurement and determination of gross alpha and gross beta radioactivity in water are important in all societies and countries of the world because of their adiobiological risks and is part of the goals of standards and public health organizations. Liquid scintillation counting technique is one of the best methods for simultaneously measuring alpha and beta-particle-emitting in water. In this technique, due to the overlap of spectra of alpha and beta, evaluation of the alpha and beta interference and the appropriate PSA value is very important for sample counting rate. The purpose of this work is to measure the activity concentration of gross alpha and beta in bottled water and compare them with the allowable limit and international standards. To achieve the goal of this research, the work was carried out in two phases. In phase 1, the alpha and beta interference and the appropriate PSA are obtained using two standard solutions of americium-241 and strontium-90 with activity of 21 and 40 Bq. In phase 2, The 10 bottled drinking water samples from different brands are analyzed using LSC. The results of the sample counting showed appropriate PSA value of 110 for the measurement of gross alpha and gross beta radioactivity in water. The measurement results showed that the gross alpha and beta activity concentrations were 41-62 mBqL-1 and 57-85 mBqL-1 which are below the allowable limit by comparing the standard limits.

Detection and dosimetry of ionizing radiation are important and fundamental issues in the nuclear industry. In this study, calculations related to the optimal thickness of a new beta detector for 90Sr source based on Polycarbonate/Bismuth oxide composite material (PC-Bi2O3) for different weight percentages of bismuth oxide fillers in polymer matrix, namely 0 wt%, 10 wt%, 20 wt%, 30 wt%, 40 wt% and 50 wt% were carried out using the ESTAR program. Results showed that the weight percentage of bismuth oxide particles was effective in determining the range and stopping power of the electrons in the composite detector. Finally, for 90Sr, using the evaluation of beta particles range in the aforementioned composite material, the optimal thickness for this detector was calculated.

The dosimetric characteristics of γ-radiation induced defects in strontium sulfate rod dosimeter were investigated using electron paramagnetic resonance (EPR) technique focusing on the dose range of 10–15000 Gy. The most significant EPR signals of spectroscopic splitting factor (g-value) g=2.0036 ¡ g=2.0090 and g=2.0160 were observed and attributed respectively to the SO4¯, SO3¯ and O3¯ peaks, which were created by gamma radiation. The intensity of the signals increases linearly with increasing absorbed doses up to 10000 Gy.
In this research, nano-crystalline of SrSO4:Dy, SrSO4:Tb and SrSO4:Dy&Tb with grain sizes of 45–55nm has been prepared by the co-precipitation method. EVA and paraffin wax were selected as binding materials for strontium sulfate. It was not observed any interferences or noises in the EPR signal. The spectrum of SrSO4 with different dopants and concentrations were compared. The results showed that SrSO4 doped with 0.2 mole % dysprosium has high intensity. Then it was chosen for comparing with pure SrSO4. The intensity of SO4¯, SO3¯ and O3¯ peaks in the dosimetry range 10-15000 Gy for both EPR dosimeters of pure SrSO4 and SrSO4: Dy (0.2%mol) were compared. The obtained results revealed increase in sensitivity and dosimetry range of SrSO4:Dy (0.2%mol) by factors of three and ten, respectively.

We synthesized various types of barium and strontium hexaferrite nanoparticles using barium chloride and strontium nitrate salts by co-precipitation method in microwave. The solvent was either water, ethylene glycol or mixture of them with three different natural surfactants. XRD and SEM analysis were performed to evaluate the morphological characters of the products. The mean diameter of barium and strontium hexaferrite particles in all products was less than 100 nm, indicating successful formation of nanoparticles. The purity of nanoparticles was documented by FT-IR spectrometry. SEM analysis shows that the nanostructures of products would change with respect to type of solvents and surfactants. So it is possible to change the size and structure of nanoparticles for various purposes with manipulation of primary parameters. In the second phase various proportions of barium chloride and strontium nitrate were used for production of nanoproducts. All the products had pure nanoparticles of barium and strontium hexaferrite which again was confirmed by XRD analysis. VSM analysis was performed to study the ferromagnetic characteristics of the products. Hysteresis curves disclosed that all the products have ferromagnetic properties. Strontium hexaferrite nanoparticles are hard ferromagnetics and barium hexaferrite nanoparticles are soft ferromagnetics and nanocomposite barium/strontium hexaferrite nanoparticles have the intermediate ferromagnetic properties.

In this article, bulk and thin film samples of strontium ferrite have been studied. Due to the high electrical resistivity in strontium ferrite, energy loss due to eddy currents reduces and because of this, it can be used in high frequency magnetic circuits. On the other hand, strontium ferrite has attracted much attention as a permanent magnet. At first, we study the preparation process of bulk samples of strontium ferrite by a solid state reaction technique. In preparation of samples, to optimize the magnetic properties, we have used the stoichiometry factor (n = Fe2O3 / SrO) of 5.25. In addition, we have used additives such as CaO and SiO2 to control grain growth. The samples have been prepared in two series: Isotropic and Anisotropic. For preparation of anisotropic samples, the magnetic field of 1T has been used for orientation of the grains during the press. Then, X-ray diffraction, Scanning Electron Microscopy (SEM), EDAX analysis and Magnetometer, was used for analyzing and comparing of structural and magnetic properties of isotropic and anisotropic samples. The results indicate that, due to the applied magnetic field, the structural and Magnetic properties of anisotropic samples improved efficiently because of the orientation of the grains during the press. In the next stage, we used bulk samples to prepare strontium ferrite thin films by Pulsed Laser Deposition technique (PLD). The Si (111) substrate has been used to prepare the thin films. Then we have studied the microstructure of thin films by X-ray diffraction, SEM and EDAX analysis. These studies on different samples show that for the preparation of crystalline phase of strontium ferrite thin films, the substrate temperature must be higher than 800˚C. The optimum conditions for preparation of strontium, ferrite thin films have been achieved on the substrate temperature of 840˚C and oxygen pressure of 75 mtorr.

The Baba-Mohammad celestite deposit is located in southwest Iran and 18km south of Gachsaran city. In these area celestite horizons is located at the contact zone of Gachsaran and Mishan formations. Based on the shape and arrangement of celestite in the evaporitic sequence, the genesis of major part is believed to be diagenetic; while a small part has been probably formed synsedimentarily by saturation of strontium ions in solutions of evaporitic environment. According to the abundance of gypsum in evaporitic environment and abundance of sulfate ions in water and low rates of strontium sulfate solubility in comparison with calcium sulfate, strontium sulphate (celestite) was formed due to the presence of strontium ions in the environment. The source of strontium is seawater or brines originated from sea water. In this way the initially mineralizing fluid is created in sabkha through the evaporation of sea water and as the brines enters into the underlying sediments, then leached significant amounts of strontium from the host sediments. When these strontium rich fluids are evacuated into the surface layer that includes carbonate and gypsum. Celestite sedimentation is occurred by the replacement of existing minerals and also through the incorporation of mineralizing fluid with sulphate-rich brines, which have been trapped inside the layers. Existence of celestite crystals along with the typical crystal habit (figure/shape) of anhydrite and gypsum indicates the replacement of these minerals by celestite. According to field observations, geological, mineralization, geochemical studies and analysis of sediment facies the Baba-Mohammad celestite deposit is a sedimentary-diagenetic deposit.

Strontium Hexaferrite Bodies attracted more attention in various industries such as: microwave, Dc motors, agriculture (irrigation) and etc. In this research, the effect of chromium ion addition on phase analysis, microstructure and magnetic propertiesof strontium hexaferrite bodies prepared by solid state synthesis have been investigated. Results show that not only molar ratio of iron oxide and strontium oxide(n = 6) but also first firing temperature(1210oC) to form magnetic phase of strontium hexaferrite andsecond firing temperature (1220oC) to obtain suitable magnetic properties of strontium hexaferrite bodies at presences of chromium must be considered. XRD and SEM investigations showed that optimum amount of chromium is 0/3 (SrCr0/3Fe11/7O19).Magnetic coercivity, remanent magnetization and rectangularity ratio (Hk/HCj) of sample were 3995 Oe, 3719 Gs and 83/5%, respectively.

Strontium hexaferrite nanocrystallites were prepared by the sol–gel autocombustion method followed by calcination at 900 °C for 1h under different molar ratios of reductant/oxidant. The structural properties of strontium hexaferrite nanoparticles were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the particle size of the resultant powder was about 50-80 nm. The photocatalytic activity of magnetic strontium hexaferrite under UV light was evaluated using Methylene blue (MB) as a model compound for organic contaminants. The maximum degradation efficiency (46%) was achieved at molar ratio of reductant/oxidizer 0.8. Reasonably high values of magnetization, the strontium hexaferrite nanoparticles could be easily separated from the environment by using a low strength magnetic field after the reaction.

In this study, barium strontium titanate/cobalt zinc ferrite composites that composed of two different magnetic phases were investigated. Pyroelectric phase consists of barium strontium titanate particles with particle size of about 150 nm and soft magnetic phase consists of cobalt zinc ferrite nanoparticles with particle size of about 30 nm. Two phases were prepared with sol-gel method and under appropriate stoichiometry. XRD analyses indicated formation of pure phase for each magnetic phases and FESEM analysis indicate the structural properties of Cobalt-Zinc ferrite and Barium Strontium Titanate nanoparticles. Investigation of permittivity, permeability and reflection loss of samples indicated the response of electromagnetic waves to these samples in the frequency range of 1-18 GHz. According to the reflection loss of composites, there are two mechanisms for the absorption of electromagnetic waves. In the first region of this frequency band, magnetic loss from Cobalt-Zinc ferrite nanoparticles is dominate and in the last region of this frequency band, dielectric loss from barium strontium titanate is dominate.