Analysis of Mosha fault by using earthquake focal mechanism

We used the focal mechanism of crustal earthquakes to estimate the magnitude and direction of the maximum principal stress near Tehran. Our assumptions are that the slip vector lies in the fault plane and is parallel to the maximum resolved shear stress in that plane. The theoretical analysis is tested using accurately determined focal mechanisms of 51 earthquakes) that occurred along the Mosha fault. The earthquake focal mechanisms in the Central Alborz are divided into seven groups with respect to their location. The method that applied here is based on a developed stress inversion of Michael proposed by Vaclav Vavrycukin 2014 by applying the fault instability constraint and the stress is calculated by iterations

Micellization and synergistic effect in an aqueous solution of an AOS-TX100 mixture: before and after equilibrium in the presence of clay

In this research, a novel surfactant mixture consisting of anionic (alpha olefin sulfonate [AOS]) and nonionic (TX100) type was developed. Possible synergistic effect in micelle formation in different mass ratios of the mixture (1:2, 1:1, and 2:1) was studied by surface tension measurement method. Rubingh's Regular Solution theory was used to evaluate the interaction parameters (β) and activity coefficient (f) for both binary mixture and single surfactants, before and after equilibrium in the presence of clay minerals (kaolinite and illite). The differences between experimentally obtained CMC values and ideally calculated values, showed nonideality of the mixtures. In addition, the lower CMC values of mixtures in comparison with individual surfactants were an indication of synergism. The synergistic effect was maintained before and after equilibrium with clay minerals. The β values of the mixture before equilibrium were in the range -1.5 to -2.6. However, after equilibrium with kaolinite, the values were in the range of -1.9 to -3.9 while after equilibrium with illite they were in the range -1 to -3. For the mixture, before and after equilibrium, the synergism became more severe as mole fractions of AOS increased in the mixture

Investigation of 99Mo potential production via UO2SO4 liquid target irradiation in a 5 MW nuclear research reactor

The activation method for 99Mo production in comparison to fi ssionable target irradiation in research reactors is less preferable. Therefore, 99Mo yield using UO2SO4 samples was theoretically investigated. Computational results revealed admirable potential of the liquid samples for 99Mo production. Low-concentrated uranyl sulphate samples could easily be handled by the irradiation box. The sample geometry optimization improves thermal hydraulic conditions and production yield. The optimized geometry including only 0.12 g 235U produced 57Ci99Mo at end-of-irradiation (EOI) with a temperature peak of 72°C during the irradiation

cis-Chloridobis(4,4′-dimethyl-2,2′-bipyridine-κ2N,N′)oxidovanadium(IV) chloride ethanol monosolvate monohydrate

In the title compound, [VClO(C12H12N2)2]Cl·C2H5OH·H2O, the VIV atom is six-coordinated in a distorted octahedral geometry by four N atoms from two 4,4′-dimethyl-2,2′-bipyridine ligands, one O atom and one Cl atom. In the crystal, O—H...Cl, C—H...O and C—H...Cl hydrogen bonds and π–π contacts between the pyridine rings [centroid–centroid distances = 3.7236 (17) and 3.6026 (19) Å] stabilize the structure. Intramolecular C—H...O and C—H...Cl hydrogen bonds are also present

Computational investigation of 99Mo, 89Sr, and 131I production rates in a subcritical UO2(NO3)2 aqueous solution reactor driven by a 30-MeV proton accelerator

The use of subcritical aqueous homogenous reactors driven by accelerators presents an attractive alternative for producing 99Mo. In this method, the medical isotope production system itself is used to extract 99Mo or other radioisotopes so that there is no need to irradiate common targets. In addition, it can operate at much lower power compared to a traditional reactor to produce the same amount of 99Mo by irradiating targets. In this study, the neutronic performance and 99Mo, 89Sr, and 131I production capacity of a subcritical aqueous homogenous reactor fueled with low-enriched uranyl nitrate was evaluated using the MCNPX code. A proton accelerator with a maximum 30-MeV accelerating power was used to run the subcritical core. The computational results indicate a good potential for the modeled system to produce the radioisotopes under completely safe conditions because of the high negative reactivity coefficients of the modeled core. The results show that application of an optimized beam window material can increase the fission power of the aqueous nitrate fuel up to 80%. This accelerator-based procedure using low enriched uranium nitrate fuel to produce radioisotopes presents a potentially competitive alternative in comparison with the reactor-based or other accelerator-based methods. This system produces ∼1,500 Ci/wk (∼325 6-day Ci) of 99Mo at the end of a cycle