معصومه خدایی

One of the periods of prominent and influential presence of scholars among the people of Iran is the Qajar era. With the rule of the Qajars in Iran, another stage of developments in Iran's history will take place and a new chapter of political and social life will be opened for Iranians. A life that is more influenced by the statements of mujtahids and scholars and their religious fatwas than in previous periods. Therefore, this research was carried out with the aim of "examining the fatwas of religious scholars for the Shiite people of Iran during the Qajar period". The library research method was done using books, articles and theses. Then, the religious fatwas of the scholars regarding the war between Iran and Russia, the "Reghi" contract, the fatwa of Mirza Shirazi, and the constitutionalism, and the fatwa of Akhund Khorasani and Sheikh Fazlullah Nouri were examined and it showed that during the Qajar era, people were most influenced by the scholars of the time and less so. They obeyed the orders and agreed to the activities of the Qajar rulers.

Concentration of hydrogen peroxide from 35% to 98 wt% is performed via the methods such as vacuum distillation and cooling crystallization, but hydrogen peroxide with concentration of ≥90%, is very sensitive to impurities and may be decompose. Therefore, the solution should be quite pure before concentration process. Herein, separation of Magnesium (Mg) cation from the commercial hydrogen peroxide solution (35 wt%) by ion exchange method using strong acid cation resin Amberlite IR-120 H+ with styrene divinylbenzene copolymer matrix and sulfunic acid functional group is investigated. Effect of the amount of resin and contact time on the separation of cation is considered. The metal ion concentration in the original solution and the metal ions left unabsorbed were determined by Inductive Coupled Plasma Spectrometry technique. Experimental results obtained from the separation of Magnesium were compared with Freundlich, Langmuir and Jovanovic adsorption isothermal models. Results show that, these isotherm models only in a certain range of concentrations, are consistent with experimental results. Although, the Langmuir equation of adsorption isotherm gives the best results.

Dimethyl amino ethane azide (DMAZ) is a good replacement of hydrazine derivatives in aerospace industries. It is produced from the reaction between dimethyl amino ethyl chloride and aqueous sodium azide. DMAZ is formed in organic phase with a purity of at least 90%. High pure DMAZ is necessary for aerospace utilization. Thermal sensitivity of DMAZ leads the purification procedure to be performed at low temperatures. So, the Distillation at sub-atmospheric pressures is a good choice for this purpose. In this paper, effect of various parameters such as temperature and pressure on the distillation time and loss of material and final purity of DMAZ was studied in regular packed column, known as vigorous column, and optimized conditions were found.

Hydrogen peroxide in high concentrations (about 98%) is considered as an important energetic substance. In this paper, the methods for the separation of impurities and ions and concentrating of commercial solution of hydrogen peroxide is investigated. The results showed that the purification has been well done via the ion exchange and distillation techniques. Also vacuum distillation and then cooling crystallization are suitable methods for the concentration of hydrogen peroxide.