Papers by Keyword: Explosive

Abstract: This research was carried out to compare the performance of ANFO and Ammonium Nitrate on fragment size distribution by using the ANFO and AN as the column charge in blasting operations, measuring the fragmentation size after each blasting operation, characterizing the fumes evolving from the blasting operation in each case and compare the performance of the ANFO and AN. The densities of the rock deposit were derived as 2.638 g/m³ and 2.622 g/m³ for Block A and Block B respectively. The rebound hardness tests ranged from 47 to 61 for Block A and Block B from 48 to 54. The total explosive charge used for each of the blocks was 0.1 kg. The muckpile magnification ratio for Block A was 0.008 and Block B was 0.004. The fragmentation sizes for Block A range from 1.869 cm to 19.411 cm and Block B from 2.414 cm to 37.177 cm. The magnification ratio and fragment sizes show that Block A has better fragmentation than Block B. Ammonia gas was not present in the area of study before blasting but the fume emitted after first blasting with ANFO produced 0.08% of Ammonia gas and after the second blasting with AN 0.07% were produced. The oxygen level was reduced from 20.9% before blasting to 19.2% after the first blasting and 19.1% after the second blasting. It was deduced that blasting with ANFO generated more Ammonia gas than blasting with AN but the Oxygen level when ANFO is used was higher than when AN is used. Keywords: Blasting, density, explosive, fragmentation, magnification ratio

Abstract: The solubility of TNT and RDX was measured in supercritical carbon dioxide fluid at 303.0, 308.0, 323.0, 338.0 K, and over the pressure range from 10.0 MPa to 50.0 MPa. This study examined the influences of extraction temperature, extraction pressure and support effect (SE) between molecules of TNT and RDX on their solubility in the TNT/RDX/SC-CO₂ system. The results show that solubility of TNT and RDX in TNT/RDX/SC-CO₂ ternary system is much higher than that in binary system. The values of SE of RDX and TNT increase first and decrease then with the pressure changing. The pressure turning point occurred over the pressure range from 25 MPa to 28 MPa for TNT and from 13 MPa to 20 MPa for RDX.

Abstract: A multi-fingered hand has been used in the explosive Disposal Robot to improve the disposal ability of explosive. Grasping ability of the multi-fingered hand is a problem with the change of grasping posture. This paper discusses grasping ability of the multi-fingered robot hand. Screw theory and BP neural network are used to optimize the joint angle of the finger. The most favorite grasping posture is calculated when the multi-fingered robot hand can withstand the largest external wrench. In order to guarantee the explosive not to be exploded under the exceeding grasp force, the weight of the explosive the multi-fingered hand can hold is also discussed in this paper. It is an important theoretical guidance for the multi-fingered robot hand handling of hazardous items.

Abstract: Oxygen coefficients of 396 explosives, including liquid and solid explosives, 177 dangerous materials, including oxidants, combustible substances, chemical hazards and narcotics, and 9 common packing materials were collected and compared. It can be seem that the explosives can be distinguished from non-explosives by oxygen coefficient with boundary 0.3 to 1.2. This result can support a convincing proof for explosive neutron detection.

Abstract: Brass plates with a diameter of 100 mm and thickness of 2.0 mm or 0.87 mm were accelerated by TNT and Comp. B charges. A plane wave generator with 100mm in diameter was used to form one-dimensional detonation within the charge. Six acceleration jumps of the plate free surface caused by the interactions between the incident and reflective waves were observed by use of a Fabry-Perot velocimeter and an image converter camera system. We believe that the experimental system adopted in present work provides a perfect technique for studying the detonation properties of the explosives and the dynamic response of materials to the impulsive loading.

Abstract: Definition of homology gene, mutual exclusion gene, formulations gene and compatriots gene set has been given based on the characteristics of the energetic formulation components in this paper. The complex formula chromosome resolution rules have been designed to solve the energetic formulation component burst speed estimate problem combined with the GEP theories and test techniques. The test results showed that the performance prediction error of the detonation velocity is less than 3%.

Abstract: Many toxic and undegradation organic pollutants to people health are existed in explosive wastewater. The conventional treatments are unable to effectively remove them. This paper treated the explosive wastewater of TNT by using a self-made discontinuity reactor, Supercritical Water Oxidation (SCWO) system. The experimental results show that SCWO is a high-efficiency, clean treatment and disposal technique for TNT explosive wastewater. Temperature and reaction time serve as the main influence factors in removing COD of wastewater, with which add, the COD removal rate obviously increases. Under no oxygen condition, partially oxidation existed in SCWO.This shows that supercritical water is a well solvent and has oxidation. At 550°C, 24MPa, and 120s and at oxygen excess 300%, the COD removal rate of wastewater is over 99% and its main toxic pollutants TNT are thoroughly disposed. The discharge standard of environmental protection is met.

Abstract: Abstract:the domestic and foreign explosive workers who have carried on the massive research work on compression resistance performance of explosives, developed a series of experimental equipment which mostly limits to the qualitative study stage. Through design proposal optimization, explosion temperature，heat of the explosion theoretical calculation as well as the experimental equipment various parts parameter computations, the stress examination had determined finally quite reasonable parameters. This paper eventually developed a set of device which are reusable, less consumable, easy operation. The practice identified the method is an effective to test compression resistance of explosive.

Abstract: The flow field, temperature field and stress field on the melt-cast explosive process have been studied by using software of Procast combined with experimental method，from which the thermodynamic characteristics of the explosives melt-casting process has been researched. The simulation results show that the charge shrinkage, cracks and pore formation could be effectively reduced by adjusting the temperature and pressure. The simulation results could be used for the optimization of casting processes, thereby improved the safety performance of Melt-cast explosive. Keywords: explosive; casting; simulation; shrinkage defects; cracks;

Abstract: To reduce safe distance such as inhabited building distance (IBD), a new type magazine, which is referred to as a subsurface magazine, has been proposed and the explosion effects have been discussed. We have conducted explosive tests by using relatively large scale models (23 kg and 78 kg in mass) and examined mass effect (scale effect) of blast waves caused by explosion of high explosives. The magazines were composed of a arch-type explosive storage room with a line hinge along the top of the roof of the wall, a square passage way to ground which will release the blast wave. Explosion hazards from the explosion of subsurface magazines were collected to understand the characteristics of airblast, fragments, and ground shocks. Safety criteria for the subsurface magazine are discussed based on the experimental results.