Tetrazoles are class of high nitrogen heterocycles. These compounds have C-N and N-N chemical bonds and thus have positive heat of formation, high density and specific high impulse. Tetrazoles have also high potential energy and low sensitivity to friction and shock and thus are used as green energetic MATERIALS in propellants, gas generators, EXPLOSIVEs and pyrotechnics. Some of tetrazole derivatives are used as green primes now. Tetrazoles have some advantages compared to classical high energy MATERIALS such as lower toxicity, easier synthesis, cleaner and environmentally friendly decomposition. As a result they are good alternative for normal energetic MATERIALS. These compounds also are used as agricultural and pharmaceutical.

Background & Aim: The most detailed information about neural activity comes from intracellular recording. Not only this technique shows the pattern of neural action potential, but it also records the cellular events which give rise to the action potential, including variations in the resting potential, changes in cellular resistance and synaptic potentials.Results: Using this method with manipulation of the composition of the bathing solution (c.hanging ionic concentrations or adding drugs) the ionic mechanisms responsible for these potentials can be identified. It is also possible to investigate the mechanisms of actions of drugs such as dental sealers on neuronal excitability.Conclusion: In the present study, intracellular recording technique has been introduced in dental MATERIALS research as a valuable method to determine the neurotoxicity of endodontic sealers on neuronal cells.

EXPLOSIVE accidents within recent years resulted in vulnerability and reduction of life of plenty of structures including sensitive and crucial structures. Sensitivity of this problem resulted in laboratory and theoretical studies for utilization of absorbent layers as energy dissipater. In this paper, behavior of two types of sandwich absorbent layers including steel honeycomb and fragile concrete composite as concrete wall guard under EXPLOSIVE loading was analyzed aiding finite element software ABAQUS. EXPLOSIVE pressure was simulated based on CONWEP method. Comparison of results obtained from analysis shows that function of said layers differs proportional to the objective and value of EXPLOSIVE samples so that although the both types of absorbent layers have a considerable effect on reduction of damage to the main structure, but in samples with low explosion intensity, fragile layer with higher energy absorption and reduction of deflection of concrete wall’s central point has better function than crushable layer and in severe explosions, due to emergence of plastic behavior, steel crumpled layers have better function.

In EXPLOSIVE Welding (EXW) process, there is a situation in which high amount of pressure in collision point leads to decrease in impurity of superficial layers and metal gets in contact with another dissimilar metal and Metallurgical bond can be initiated at the interface. In this paper, in addition to introduction of scarf welding, EXPLOSIVE welding of aluminium to copper plate in different conditions of EXPLOSIVE loading performed and shear strength of bond was evaluated through new method. The Relationship between shear strength and EXPLOSIVE loading was demonstrated by establishment of non-linear and logarithmic models through regression method and ANOV A table. Adequacy of the developed models was verified in EXPLOSIVE cladding process. Consequently, EXPLOSIVE loading varieties can be evaluated in one experiment by production of scarf joint between dissimilar metals (according to the computational method employed in this paper) and with development of proper model, the shear strength of cladding metals can be estimated.

Fuel–air EXPLOSIVE devices are used to disperse liquid fuels into open atmosphere and create detonation waves in the resultant cloud. To numerically study of flow field inside the cloud, the initial conditions of injection as well as the droplet initial size should be designated. In the present paper the primary break up of liquid fuel dispersed from a FAE device was simulated by using film instability model and a computer code was written to perform the calculations. Experimental results were used to validate the numerical one and the estimated droplet initial mean size was given to a far field simulation code as input data. Then the result of this latter simulation was compared with the related experimental results. With regard to numerical and experimental results, we proposed an interval to estimate the initial size of droplet dispersed from a FAE device. Generally, the results show mean droplet diameter is of centimeter order of magnitude.

In this paper, the sympathetic detonation is studied. In this type of detonation, the shock wave of an EXPLOSIVE by passing through a neutral environment (gap) induces the detonation in the second EXPLOSIVE. The study of this phenomenon is important to the safety of the ammunition depot and their transportation. In the present study, the sympathetic detonation in Comp-B has been studied. In this regard, the effect of the thickness of the gap and the type and composition of the MATERIALS used as the barrier in preventing the occurrence of sympathetic detonation has been investigated. The results showed that a thick layer of fine sand, held by thin layers of polymeric material, is more efficient than other MATERIALS and can prevent sympathetic detonation well. The results indicate that a 20 mm single iron barrier and also 20 mm barriers consisting of sand + Plexiglas, sand + epoxy and sand + rubber prevent from the sympathetic detonation of the Comp-B acceptor.

Dear Editor, Dengue fever with four related dengue viruses (DEN-1, DEN-2, DEN-3, DEN-4) is transmitted to humans by some species of invasive female Aedes mosquitoes, such as Aedes aegypti and Aedes albopictus, and it is rapidly spreading in the world. It seems that the causes of increasing cases and EXPLOSIVE spread of dengue fever are somehow related to the vectors of this disease. These factors include: 1-Global warming due to human activities and creating favorable living conditions and reproduction of Aedes mosquitoes. 2- Numerous seasonal rains that create temporary and suitable larval habitats and breeding places for Aedes mosquitoes. 3- The presence of numerous larval habitats for Aedes mosquitoes; They lay eggs anywhere there is stagnant water: in discarded used tires, in broken containers that hold water and septic tank valve pipes, and even in abandoned cans. 4-Unlike other mosquitoes that only bite once and feed once before laying eggs; Invasive Aedes mosquitoes, especially Ae. aegypti, have repeated bites daily, and multiple and repeated bites cause more transmission of dengue fever virus and its EXPLOSIVE spread. 5- Aedes mosquitoes infected with one of the dengue fever virus serotypes vertically transmit the virus to their next generation; That is, Aedes infected with the virus also lay infected eggs, and from the infected eggs, the infected adult mosquitoes eventually come out, which are infected with the virus from the beginning without having a blood meal from the infected human reservoir, and with their first blood meal, they get fever. They transmit dengue to a susceptible host (human).