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1.
Soltanolkottabi Fariba Talaie M R Aghamiri Seyedfoad Tangestaninejad Shahram 《Journal of the Iranian Chemical Society》2020,17(1):17-24
Journal of the Iranian Chemical Society - The primary objective of the present work was to investigate the effect of fluid movement on synthesized chromium-benzenedicarboxylate, MIL-101(Cr),... 相似文献
2.
S. M. Abtahi S. M. R. Aghamiri H. Khalafi 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(1):287-301
The first purpose of this research was improvement of sensitivity of the normoxic acrylamide-based polymer gel dosimeter. Another aim of this study was investigation of the absorbance of the irradiated gels as well as their relaxation rate variations. In addition, a new optical parameter, area under the absorbance spectrum (AUS), was investigated. Sensitivity improvement was performed by adding glucose and urea to the previously reported acrylamide-based polymer gel formulation and new formulation was named PAGATUG. The formulation which gives the nearest tissue elemental composition has been determined to be 3 % bis, 3 % AA, 5 % gelatine, 5 mM THPC, 0.01 mM HQ, 8.5 % glucose, and 3 % urea. The differences in electron density, number of electrons per gram and effective atomic number of PAGATUG gel were no more than 1, 0.5, and 0.8 % of the corresponding values for the soft tissue respectively. PAGATUG gels were irradiated by 60Co radiotherapy unit photon beams with different doses and imaged using a 1.5T Siemens Avanto MRI scanner for different post irradiation times. In addition, the absorbance of the irradiated gels were evaluated using a double beam spectrophotometer. We found that the R 2-sensitivity of polymer gel was improved by a factor of more than 2.6 in respect of the previously reported PAGAT polymer gel. Dose–absorbance sensitivity was obtained as 0.89 Au Gy?1 and the results showed more stable response in respect of R 2 investigation. An AUS-sensitivity of 107.7 Au nm Gy?1 indicated to steep response variation. This read out parameter showed an acceptable linearity and dynamic dose range. 相似文献
3.
Saeed Seyfi Seyed Foad Aghamiri Masoud Beheshti 《Journal of Dispersion Science and Technology》2013,34(4):536-550
In this work, the primitive SAFT equation of state along with three different hard-sphere equations was used to correlate and predict mean ionic activity coefficients of aqueous electrolyte solutions. The mean ionic activity coefficient of aqueous electrolyte solutions was considered as the contribution of hard-sphere and dispersion effects. The Mansoori (M), Wang-Khoshkbarchi-Vera (WKV) and Ghotbi-Vera (GV) hard-sphere equations were applied in correlating the mean ionic activity coefficient of electrolyte solutions. The comparison among above indicated equations was shown. First, vapor pressure and densities of water in the temperature range of 373.15 to 423.15 K was regressed by SAFT equation of state. In the restrictive primitive mean spherical model, ions were hard spheres without any chain structure. Neither association effects were considered in this study. Clearly, in common used five SAFT parameters were decreased to three, which were calculated by using the experimental mean ionic activity coefficients of electrolyte solutions. The comparison among three hard-sphere equations of state approved that Ghotbi-Vera hard-sphere model (GV) correlated the experimental data accurately than the others; two hard-sphere models. The mean ionic activity coefficients of some electrolyte solutions were being predicted by taking the advantage of the regressed values surely, in a wide range of molality. 相似文献
4.
Zahra Nickmand D. D. Do D. Nicholson Seyed Foad Aghamiri Mohammad Reza Talaie Khozanie Hasan Sabzyan 《Adsorption》2013,19(6):1245-1252
We have used Grand Canonical Monte Carlo simulation to study argon adsorption at 87 K in wedge shaped mesopores. The structural parameters, including mean pore size, wall length and wedge angle, were varied to investigate their effects on the size, shape and the position of the hysteresis loop. Although the effects of pore size have been studied previously, the wall length and wedge angle have received little attention. We find that the wedge angle can have a significant effect on the existence, position, size and shape of the hysteresis loop, while the wall length affects the adsorptive capacity associated with the loop and the behaviour of the isotherm beyond the loop. The results of this work have far-reaching consequences for the characterization of pore size distribution where it is commonly assumed, when constructing a kernel of local isotherms, that pore size is uniform, since even a small deviation from a constant pore width can shift the condensation and evaporation pressures significantly and thus lead to an incorrect estimation of pore size. 相似文献
5.
S.M.R. Aghamiri 《Optics Communications》2008,281(3):356-359
Analyzing the effect of ionized gamma irradiation on the optical parameters of materials is a solution for finding newer techniques in the field of detector and dosimeter systems. A PMMA (polymethylmethacrylate) polymer was radiated from a 60Co source with a power of 1800 C and a constant dose rate of 1.44 kGy/h in three steps of 5, 25 and 61.2 kGy. The ionized gamma irradiation affected the refractive index of polymer and therefore it changes the polarization of the incident light. The difference in the polarization phase shift of the polymer depended on the dose it had been irradiated with. 相似文献
6.
I. Jabbari M. Shahriari S. M. R. Aghamiri S. Monadi 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(3):831-837
The energy deposition mesh tally option of MCNPX Monte Carlo code is very useful for 3-Dimentional (3D) dose calculations.
In this study, the 3D dose calculation was done for CT-based Monte Carlo treatment planning in which the energy deposition
mesh tally were superimposed on merged voxel model. The results were compared with those of obtained from the common energy
deposition (*F8) tally method for all cells of non-merged voxel model. The results of these two tallies and their respective
computational times are compared, and the advantages of the proposed method are discussed. For this purpose, a graphical user
interface (GUI) application was developed for reading CT slice data of patient, creating voxelized model of patient, optionally
merging adjacent cells with the same material to reduce the total number of cells, reading beam configuration from commercial
treatment planning system transferred in DICOM-RT format, and showing the isodose distribution on the CT images. To compare
the results of Monte Carlo calculated and TiGRT planning system (LinaTech LLC, USA), treatment head of the Siemens ONCOR Impression
accelerator was also simulated and the phase-space data on the scoring plane just above the Y-jaws was created and used. The
results for a real prostate intensity-modulated radiation therapy (IMRT) plan showed that the proposed method was fivefold
faster while the precision was almost the same. 相似文献
7.
Tramadol is a centrally acting analgesic‐anodyne agent of high oral bioavailability. The tramadol contains a weakly absorbing chromophore in its molecule and it was determined by kinetic spectrophotometric method in pharmaceutical, urine, and blood plasma. Response surface methodology and the central composite design was applied to study the influence of maximum sensitivity, reagents concentration, temperature, and time on the UV–Vis spectrophotometry analysis of tramadol. Analysis of variance showed a high coefficient of determination (R2) value for responses, confirming adjustment of the models with experimental data. The change in absorbance was followed spectrophotometrically at 478 nm. Under optimum experimental conditions, calibration curve was linear over the range 0.45–100.0 μg/L of tramadol. The limit of detection was 0.12 μg/L of tramadol. The developed method was successfully applied for the determination of tramadol in real samples. 相似文献
8.
H. Poorbaygi Sh. Sheibani S. M. R. Aghamiri M. Azizi Shamami 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(1):429-434
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. 相似文献
9.
Mitra HajipourSeyed Foad Aghamiri Hassan SabzyanFakhry Seyedeyn-Azad 《Fluid Phase Equilibria》2011,301(1):73-79
Configurational-biased Gibbs ensemble Monte Carlo simulations were performed to obtain the phase behavior of the homologous series of primary alcohols from ethanol to 1-heptanol. Molecular interactions in these systems are modeled by a newly developed exp-6 potential in combination with a Coulombic intermolecular potential. Some of exp-6 potential parameters required to describe these alcohols were taken from the previous literature data reported for methanol and n-alkanes. The oxygen's potential parameters were optimized to fit the coexistence curve of these alcohols to the experimental data. Simulated values of saturated liquid and vapor densities, vapor pressures and critical constants of the alcohols are in good agreement with experimental data. The efficiency of the new model in the prediction of binary phase diagram of water/ethanol and n-hexane/1-propanol mixtures is also evaluated. The calculated mole fractions in the vapor and liquid phases of these binary mixtures also show satisfactory agreement with the experimental data. 相似文献
10.
Rong Li Seyed Foad Aghamiri Dongjie Yang P. Chen 《Journal of Dispersion Science and Technology》2013,34(5):709-715
In the article, the dynamic surface tension of sodium lignosulfonate (SL) aqueous solutions are investigated using an axisymmetric drop shape analysis-profile method. The data are analyzed by the Langmuir, Frumkin, modified Frumkin, and modified Flory-Huggins equations. The results indicate that the Langmuir model's results with two adjustable parameters are comparable to that of other models with three or four adjustable parameters. Based on the simplicity of simulation, the Langmuir adsorption equation is used to correlate the dynamic adsorption processing. The aggregation between SL molecules and the variation of adsorption configuration are proposed to interpret the results of dynamic surface tension. 相似文献