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To better understand the influence of the aluminum content on the performance of aluminized explosives, experiments in concrete and cylinder tests were performed. Three types of RDX-based aluminized explosives, in which the mass ratio of aluminum content was 0%, 15%, and 30% were considered in this paper. The shock wave pressures of the aluminized explosives in the affected concrete bodies were measured using manganin pressure sensors. The acceleration ability was obtained using a high-speed camera and a rotating mirror streak camera. The peak pressure attenuation characteristics of the explosives with various aluminum contents indicated that a higher aluminum content is associated with a slower peak pressure attenuation of the shock wave. In addition, the results of the cylinder tests and the metal-rod acceleration tests revealed the influence of the aluminum content on the acceleration ability of explosives in three different time periods. The test data presented in this paper verified the relationship between the aluminum content and explosive performance, which is of great significance for optimizing the properties of aluminized explosives. V C 2014 AIP Publishing LLC. [http://dx.

Polymer-bonded explosives (PBXs) are typical particulate composites of energetic crystals in a polymer matrix, which have a volume fraction of 60% to 95%. They are engineered to provide reliable performance and maximum safety envelopes through reduction of their sensitivity. There are three kinds of polymer-bonded explosive materials; namely, PBX1, PBX2, and PBX3. The last two polymer-bonded explosives were recently invented, in search of the more insensitive polymer-bonded explosive but with high detonation energy also. To investigate the dynamic response of new materials, the uniaxial compressive stress-strain behavior of the three polymer-bonded explosives was investigated as a function of temperature and strain rate. Constant and non-constant strain rate loading experiments were conducted in the use of pulse shapers. By comparing two different loads, the strain rate effect of these materials was found to depend on the instantaneous strain rate. The variations in failure stress, and failure strain with temperature, strain rate, and material composition were examined. The dependence of compressive strength on temperature and strain rate can be attributed to the Young's modulus and fracture surface energy according to Griffith criteria for fracture. The axial splitting caused by brittle fracture for most conditions was also investigated. Another failure mode of PBX2 agreed with the Mohr's failure mode criterion. All results show that PBX2 has more stable mechanical behavior and higher detonation performance.

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A communication system plays an important role in SCADA system, and various communication media have been applied to meet the SCADA system's objective. Wireless communication becomes an attractive option as communication network in some cases, such as small amount of data communication for extremely remote substation, remote debugging temporarily for newly-built generation plants and backup communication. This paper presents a communication system using general packet radio service(GPRS) and code division multiple access (CDMA) wireless communication networks in SCADA system. Several technologies for GPRS and CDMA networks such as Access Point Name(APN), IP security protocol(IPSec), VirtualPrivate Network(VPN), packet assembly disassembly and dualnetwork online synchronously have been newly developed. Pilot project as proof-of-concept in Henan province of China was done, before going for large scale deployment. It is eventually revealed that, although being a little slower in response to sudden faults in power networks if compared with wired communication networks, this wireless communication system is still of great significance to many practical uses in SCADA system.