Theoretical prediction of the trigger linkage, cage strain, and explosive sensitivity of CL-20 in the external electric fields.

In order to add safely external electric fields into the systems of the explosives with strong cage strain, the effects of the external electric fields on the strengths of trigger linkages, cage strain energies (CSEs), surface electrostatic potentials (ESPs), as well as impact and shock initiation sensitivities of CL-20 were investigated using the B3LYP and M06-2X methods with 6-311++G(2d,p) basis set. The results show that the changes of the strengths of the N-NO2 bonds are more notable than those of the bonds forming cage, and the changes involving the N-NO2 bonds attached to the five-membered ring are more significant than those attached to the six-membered ring. In most cases, the CSEs in the electric fields are stronger than those in no field. From the BDEs, the N-NO2 cleavage is the decomposition reaction pathway in detonation initiation. However, from the surface ESPs, the N-NO2 cleavage, C-N and C-C bond breaking may initiate the reactions. The global ESPs are more reasonable and reliable to estimate the impact sensitivities of the cage-shaped explosives. The changes of the bond lengths, Mulliken bond orders, nitro group charges and BDEs correlate well with the external electric field strengths. Interestingly, an abnormal result is found that the h50 values in the electric fields are larger than those in no field.

[Application and progress of Fourier transform attenuated total reflection infrared spectroscopy].

With the application of Fourier transform infrared spectrograph and the development of chemical metrology, Fourier Transform Attenuated Total Reflection Infrared spectroscopy (ATR-FTIR) has become a kind of beneficial tool and means for analyzing samples, for which traditional transmission way does not work quite effectively, and for analyzing surface layer structure. ATR-FTIR has been applied to every realm such as spinning and weaving, quality testing, public security and so on. At present, people are launching applied study based on specific property of ATR-FTIR. Therefore, this paper mainly introduced the present study situation and development situation of ATR-FTIR, including theoretical development for depth profiling, qualitative analysis of material surface, quantitative analysis of mixture and solution component, and the application of fiber as ATR appurtenance. In addition, some special fields were also involved, such as inspecting hollow cored fiber's structure and change of orientation, and studying effective mechanism about skin promoter.