Showing 10 results for Water
یونس موسائی اسکوئی,
Volume 10, Issue 1 (7-2014)
Abstract
To obtain water resistant ANFO explosive, in this article, the effect of usage of some components were investigated. To this aim, after some screening tests, four components including guar gum, borax, Eremurus and superabsorbent sodium polyacrylate were selected. To determine and optimize the percentage of components in the mixture, design of experiments in Minitab software was used. Finally, the optimize product including 90% ANFO and 10% of mixture of four compounds introduced in screening test, were obtained which the water penetration into 100gr of this product (in 250ml graduated cylinder, after 12 hours) was about 10 mm.
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Volume 10, Issue 2 (12-2014)
Abstract
During the TNT production process, raw product includes about 4.5% of asymmetric TNT isomers. In order to use TNT for military purposes, TNT asymmetric isomers should be removed. Purification of crude TNT is done by selite (15% solution of sodium sulfite). Because of its color, the term red-water is used for this wastewater. Different methods including incineration, microorganisms, conversion of sulfone group to safe groups, oxidation with resin and zero valent iron nanoparticle are used for removal of TNT red water. Regarding the composition and the volume of the red water that should be removed, and also the process expenses, one or combination of these methods could be employed for removal of red water. In this article, all the mentioned methods for removal of red water and their influencing factors are reviewed.
Dr Yones Mosaei Oskoei, , , ,
Volume 11, Issue 1 (9-2015)
Abstract
In order to use TNT in military industries, its impurities have to be removed. The further nitration of m-nitrotoluene (by-product of the first step nitration), cause to the formation of asymmetric products which during the purification step, these tri-nitrated and asymmetric products lead to the formation of red water as a main environmental pollutant. This pollutant remains in the environment for a long time and cause several environmental pollution. Hence, avoiding from m-nitrotoluene production in the first step of nitration is a key point in the prevention of red water formation. So, several modified nitration methods are being investigated as green methods. In this paper, we review the new toluene nitration methods by changing the nitraton agents, catalysts, intermediate reactions, procedure kinetics, mechanism, and process engineering.
Dr. Farhoud Kalateh, Rafiq Fani,
Volume 11, Issue 4 (12-2016)
Abstract
In the present study, three dimensional (3D) finite element (FE) simulations of a steel water storage elevated tank for different tank aspect ratios, percentages of water stored in the tank, tank wall thicknesses and effect of baffle in tank have been performed using the FE software ABAQUS. The coupled Euler–Lagrange (CEL) formulation in ABAQUS has been adopted herein which has the advantage of considering the coupling of structural mechanics and fluid mechanics fundamental equations. The maximum hoop stress, shear stress and plastic strain in the tank wall and displacement, base shear and moment in the whole model have been studied. It is observed that stresses and strain increase with decreasing percentages of water stored in the tank and decreasing wall thickness. Displacement, base shear and moment decrease with increasing of percentages of water stored in the tank.
Mohammad Mirzaei, Saeed Babaee, Seyed Ghorban Hosseini,
Volume 14, Issue 1 (3-2019)
Abstract
In this research a new type of magnetic Pb(II) and Cr(VI) ion-imprinted polymers were synthesized using Fe3O4@SiO2 magnetic particles as supporter, benzoyl phenyl hydroxylamine and dithizone as ligands for Pb and Cr ions respectively, 4-vinyl pyridine as functional monomer, ethylene glycol dimethacrylate as crosslinker and 2,2′-azobis(isobutyronitrile) as the initiator. The ionic templates were achieved by using HCl 2M as an eluent solution. The chemical structure, morphology, thermal behaviour and magnetic properties of the sorbent polymers were evaluated using Fourier-transform infrared spectroscopy, scanning electron microscopy, thermal gravimetric analysis and vibrating sample magnetometry methods. Optimization of affecting parameters of the adsorption of analytes including of medium pH, adsorption time, kind and concentration of the eluent solution, elution time and adsorption temperature were performed using flame atomic absorption spectroscopy method. The results showed that the maximum adsorption capacities for lead and chromium were 92.3 and 96.8 milligrams per gram in media pH of 6 and 3 under 40 ◦C temperature respectively. The synthesized sorbents had high selectivity and were successfully applied for these pollutants removing from waste waters of the various stages in the ammonium perchlorate production process.
Dr. Ahmad Mollaei, Mr. Ali Mohammadi, Yahya Ebrahim Abadi,
Volume 14, Issue 2 (6-2019)
Abstract
Plastic bonded explosive PBXN-103 as an underwater charge based on energetic binder system uses in warhead section of several navy weapons. Metriol trinitrate (MTN), triethylene glycol dinitrate (TEGDN) and pelletized nitrocellulose are basic ingredients of binder system in PBXN-103 formulation. In this research the effects of applying accessible Poly glycidyl nitrate (PGN) as binder, were investigated on physical, mechanical, thermal, and sensitivity properties of PBXN-103. Results were indicated that the binder replacement enhanced obviously the tensile strength and elongation to 85 psi and 70 % respectively. Based on differential scanning calorimetry (DSC), the thermal stability of formulation was increased 20 °C in comparison with PBXN-103 and reached to 190 °C. Glass transition temperature, vacuum thermal stability, impact sensitivity and friction sensitivity were -54 °C and 4.06 ml/g/48h, 7 N.m and 7.2 kg.F respectively. This new formulation was not fired by exploding No. 8 commercial electric detonator.
Rahimeh Esmaeelzadeh, Reza Arami,
Volume 15, Issue 1 (3-2019)
Abstract
Formation of waste water from military industries and also accumulating of energetic materials from incomplete explosion could cause to penetration of energetic materials to ground and underground waters. The issues of this penetration could be catastrophe. Therefore, proper manners, in order to infiltration of these waters, must to be implemented. Attention to variety energetic materials, best method, is the method that could infiltrate and remove the major of energetic materials form wastes. Attention to importance of environmental friendly methods, this paper was investigated bio methods which could remove the energetic materials from waste waters, such as phytoremediation, bioreactors, usage of microbes and other technics and their disadvantage and advantage.
Amir Reza Ahadzadeh, Doctor Morteza Ghafoori,
Volume 16, Issue 1 (3-2020)
Abstract
In this article, the history, different types applications, literature and common terms in the field of civil explosives and some special tests of this type of explosives and finally the hazards of working with these products have been studied. Modern commercial or civil explosives based on ammonium nitrate were developed during the 1950s. These products are widely used in mining, road construction, tunneling and other construction activities and play a major role in the economic growth of countries. Slurries, water-gels, emulsions, dynamites and ANFO are the currently being produced and consumed civil explosives. Special terms in the field of production, characterization, classification and consumption of civil explosives are common, including permissibility, water resistance, COD, pressure desensitization, incendivity, etc. The sensitivity and safety of civil explosives is different from that of military explosives. For this reason, accidents related to civil explosives are mainly due to the user's unfamiliarity with the properties of these compounds. The field of production and work with civil explosives requires a chemistry and engineering vision in order to research and develop these useful products without incident.
Amir Reza Ahadzadeh, Doctor Morteza Ghafoori,
Volume 16, Issue 2 (12-2020)
Abstract
The type of sensitizer used in commercial explosives is one of the important factors in determining the cost of production as well as the safety, performance, shelf-life and application characteristics of commercial explosives. In this paper, various sensitizing agents that are currently used, including aluminum powder, monomethyl ammonium nitrate, chemical gassing, microballoons and porous ammonium nitrate prills, have been investigated. In the past, molecular explosives such as nitrocellulose and TNT were used to sensitize commercial explosives. In order to reduce the problems and risks of production, transportation and use, self-explosive materials were gradually replaced by new methods. The use of aluminum powder or organic nitrate amines in combination with micrometer air bubble sources such as microballoons, chemical gassing and porous materials completely release the high-energy capacity of commercial explosives along with increasing performance, adjusting production costs and increasing efficiency of blasting operations. Styrofoam, perlite and some other porous materials have also been tested but are not operational due to some problems. Optimal sensitizing agents maintain the advantage of relatively low sensitivity of commercial explosives and at the same time the desired initiation of these compounds by using suitable primers in blasting operation. Thus, the need for higher hazard class compounds for initiation of commercial explosives is eliminated and the cost of production is reduced.
Somayeh Jafari, Seyed Mehdi Pourmortazavi, Ali Ehsani,
Volume 19, Issue 2 (8-2024)
Abstract
The oxygen generator candle that has a pyrotechnic functional mechanism, is one of the common systems for supplying oxygen in military and civilian planes, submarines, spacecraft and ... Due to the thermal decomposition of chlorates and perchlorates during the combustion of the candle, the byproduct of chlorine gas is released, which is important to accurately measure. In this work, we got help from the high adsorbability and catalytic activity of MOF compound for developing of free chlorine electrochemical sensor which is equivalent to chlorine dissolved in water. For this purpose compound of ZIF-8 was synthesized and incorporated whit CuO nanosheets to modify the glassy carbon electrode (GCE) and supply the new sensor for free chlorine determination. FESEM, EDX, XRD, and FT-IR teqnicues was applied to characterize the fabricated ZIF-8 and CuO-ZIF-8 composites. Cyclic voltammetry and electrochemical impedance spectroscopy have been utilized for the electrochemical characterization of CuO-ZIF-8/GC modified electrode and demonstrated the sensor's ability to measure the chlorine. Using differential pulse voltammetry and under optimal conditions, the built CuO-ZIF-8/GC modified electrode showed a linear response in the range of 0.25 to 60 ppm with a detection limit (LOD) of 12 ppb towards free chlorine concentration
