ABSTRACT
The title cobalt coordination polymers, catena-poly[[[aquatripyridinecobalt(II)]-mu-tetrachloroterephthalato] pyridine solvate], {[Co(C(8)Cl(4)O(4))(C(5)H(5)N)(3)(H(2)O)].C(5)H(5)N}(n), (I), and catena-poly[[[diaquadipyridinecobalt(II)]-mu-tetrachloroterephthalato] 1,4-dioxane trihydrate], {[Co(C(8)Cl(4)O(4))(C(5)H(5)N)(2)(H(2)O)(2)].C(4)H(8)O(2).3H(2)O}(n), (II), have been prepared with tetrachloroterephthalic acid (H(2)BDC-Cl(4)) under different solvent media. Both complexes form infinite cobalt(II)-tetrachloroterephthalate polymeric chains. In (I), two independent Co(II) ions are six-coordinated through N(3)O(3) donor sets in slightly distorted octahedral geometries provided by two carboxylate and three pyridine ligands, and one water molecule. The structure of (II) contains two independent Co(II) atoms, each lying on a twofold axis, which adopt a tetragonally distorted N(2)O(4) octahedral geometry via two carboxylate groups, two pyridine ligands and two water molecules. The different stoichiometry of coordinated and solvent guest molecules leads to different two-dimensional supramolecular networks, with (I) utilizing C-H...pi and weak pi-pi interactions and (II) utilizing mainly conventional hydrogen bonding.
ABSTRACT
In this paper, combustion characterization of pyrotechnic composition is investigated using a remote sensing Fourier transform infrared spectrometry. The emission spectra have been recorded between 4,700 and 740 cm-1 with a spectral resolution of 4 cm-1. The combustion temperature can be determined remotely from spectral line intensity distribution of the fine structure of the emission fundamental band of gaseous products such as HF. The relationship between combustion temperature and combustion time has been given. Results show that there is a violent mutative temperature field with bigger temperature gradient near combustion surface. It reveals that the method of temperature measurement using remote sensing FTIR for flame temperature of unstable, violent and short time combustion on real time is a rapid, accurate and sensitive technique without interference the flame temperature field. Potential prospects of temperature measurement, gas product concentration measurement and combustion mechanism are also revealed.
