Boronic combustion analysis

Li, LiN, MgB, Sn, Pb, and so on. For the first time, P-BN (wurtzite-like form) was discovered at X-ray analysis of boron combustion products in the mixture with metal magnesium. In those experiments, was also detected as thin... 

It is seen by examination of Table 1.11(b) that a wide variety of techniques have been employed including spectrophotometry (four determinants), combustion and wet digestion methods and inductively coupled plasma atomic emission spectrometry (three determinants each), atomic absorption spectrometry, potentiometric methods, molecular absorption spectrometry and gas chromatography (two determinants each), and flow-injection analysis and neutron activation analysis (one determinant each). Between them these techniques are capable of determining boron, halogens, total and particulate carbon, nitrogen, phosphorus, sulphur, silicon, selenium, arsenic antimony and bismuth in soils. 

In the first approach, the temperature-time profiles of the combustion wave are measured using thin thermocouples (Zenin et al, 1980 Dunmead et al, 1992a,b,c). In the work of Zenin et al (1980), 7-/im-diameter microthermocouples protected by a layer of boron nitride were used. The temperature-time profiles were analyzed using the one-dimensional heat conduction equation with heat generation (see Section IV,A, 1) taking numerical derivatives of the spatial temperature distribution. An implicit assumption in the analysis is that the combustion wave is stable and planar at both the macro- and microscopic scales. 

BN-Si02 ceramics appear to be remarkable among the structural materials based on boron nitride. It was obtained by combustion of B-Si02-N2 and was studied using infrared spectroscopy and X-ray analysis [86]. The obtained data prove that the composite mainly consists of hexagonal boron nitride and... 

The microstructure of products of ferroboron combustion in nitrogen has various morphological forms. At the same time, a significant difference is visible in shape of particles of external and central parts of the burned sample. The presence of amorphous boron in the original material influences the process of nitride formation because (according to XRD analysis) amorphous boron contains boric acid which decomposes during combustion forming boric anhydride and water. 

S.B. (1997) Thermal analysis studies on the boron-potassium perchlorate-nitrocellulose pyrotechnic system. J. Therm. Anal., 49, 1327. Kuwahara, T., Matsuo, S. and Shinozaki, N. (1997) Combustion and sensitivity characteristics of Mg/Tf pyrolants. Propellants Explos. Pyrt ech., 22, 198. Koch, E.-C. (2005) Metal/fluorocarbon pyrolants VI. combustion behaviour and radiation properties of mag-nesium/poly(carbon monofluoride). Propellants Explos. Pyrt ech., 30, 209. Koch, E.-C. (2010) Metal halocarbon combustion, in Handbook of Combustion, New Technologies, Vol. 5 (eds M. Lackner, F. Winter and A.K. Agarwal), Wiley-VCH Verlag GmbH, Weinheim, pp. 355-402. 

---