Donor charge

Card Gap Test. Results are given on NMe and mixts of NMe with TeNMe. A mixt having a slightly neg OB gave the highest value of 75 cards (Ref 35), Another gap test is given in Ref 22 with a donor charge of 50g of PETN/Mn 95/5 the max gap for deton transfer was found to be 3mm... 

Pentolite at d 1.56g/cc is used as the standard donor charge in the NOL Large Scale Gap Test" (Ref 10)... 

Note 1 The bulk electrical conductivity of an intrinsically conducting polymer is comparable to that of some metals and results from its macromolecules acquiring positive or negative charges through oxidation or reduction by an electron acceptor or donor (charge-transfer agent), termed a dopant. 

For determination of growth to detonation in expls as acceptors AP (Ammonium Perchlorate), Comp C-4, and Pentolite were used and as donor charges Pentolite pellets. As barrier (gap) material Plexiglas disks were used... 

Modified Influence (Propagation) Test. Gawthrop (Ref 1) and others used a modified gap test to determine the relative ability of a shielded donor charge to transfer detonation over an air gap to an acceptor charge. Clark (Ref 2) also used this method for the determination of the gap in the transmission of detonation from a small charge (0.5 to 2g) of HE to a cartridge of 40% straight dynamite... 

Geometry is the chief obstacle to reverse detonation. When the advancing shock front encounters the cone at the base of the cavity in which the acceptor charge is placed, the wave is transmitted normal to the surface of that juncture, and spatially dissipated away from the donor charge. It is therefore possible to place equivalent charges in proximity, while maintaining reliable go/no-go performance... 

The effectiveness of one chge in initiating another is determined by the props of the expl, its loading density, and the dimensions confinement of the chge. The effective output of a donor charge increases systematically with its diameter. The optimum diameter of an acceptor, from the point of view of the air gap across which it can be initiated, is slightly less than the diam of the donor, especially for well confined columns of expls... 

The minimum shock wave pressure that causes complete detonation of the explosive under test is a measure of shock sensitivity of the explosive and is determined with the help of a gap test . The principle of this test is to subject the explosive under test to the action of a shock wave of known pressure generated by means of a calibrated donor charge and a shock wave pressure attenuator. 

Tetryl has been used as an expl since 1906. In the early part of this century it was frequently used as the base charge of blasting caps but is now replaced by PETN or RDX. During WWII it was used as a component of expl mixts (see Tetrytols in this Vol). Tetryl is still used in military boosters and leads (the expl component of a fuze between the detonator and booster), but even here it is being replaced by plastic-bonded or waxed RDX and HMX expls. A widely used shock sensitivity test employs Tetryl as the donor charge (see Shock Sensitivity of ... 

Some of the complex phenomena occurring in a gap-test with a Tetryl donor charge were investigated in Ref 27. A result of some importance to our subsequent discussion is that the pressure of the NOL LSGT drops to about 1 kb in about 2 microsecs... 

Often the heteroatom is the most nucleophilic center in the molecule, for instance, in imidazole, In such cases the electrophile, e.g., a halogen molecule or the catalyst (a Lewis acid for Friedel-Crafts type reactions) may interact with the heteroatom with formation of complexes of various kinds (w-donor, charge-transfer, etc.). 

A charge of explosives or blasting agent receiving an impulse from an exploding -> Donor charge. 

The gap test explosive train is directed from bottom to top. The donor charge (cyclonite with 5% wax) is placed into a plexiglas tube and covered with water. The acceptor charge to be tested is introduced into the water column from above. The distance between the two charges can be easly varied. 

Figure 6.12 schematically shows the set-up of the gap test. Typical values for the donor charge are 10 g RDX (with 0.6 g PETN detonator). The medium is water... 

For the gap test as a method to describe the detonability we selected the BICT procedure Donor charge of 10 g RDX/wax-95/5 (A = 1.6 g/cm ) and a test charge of 0 25 mm x 25 mm with water as gap material. The relatively small dimensions become critical when less sensitive materials (TATB, NTO) were tested. 

Recent work focuses on non-classical mesogenes which are built up by self-assembly. One example is a family of polymers containing disk-like groups which form no liquid crystalline phase, but ean act as an electron acceptor or donor. Charge transfer complexation with a complementary low molecular mass compound induces nematic or columnar discotic liquid crystalline order [153,154]. Figure 13 demonstrates this with the example of a polyester, bearing electron-rich tetra(alkoxy)tri-phenylene-units in the main chain, mixed with the electron deficient aromatic 2,4,7-trinitro-9-fluorenone (TNF). While the pure polymer shows a non-ordered isotropic melt, a columnar phase appears on addition of TNF. 

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