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C9H6Br6, hexagonal, P63/m (no. 176), a = 8.8911(3) Å, c = 10.6847(5) Å, V = 731.48(6) Å3, Z = 2, Rgt(F) = 0.0441, wRref(F2) = 0.1094, T = 293 K.

Two novel CoII metal–organic frameworks {[Co(BIMB)2(H2O)2](SO4)·EG·3 H2O}n (I) and {[Co(TIMB)2](SiF6)}n (II) were hydrothermally synthesized by corresponding metal salt with organic ligands 1,3,5-tris[(1H-imidazol-1-yl)methyl]benzene (TIMB) or 1,4-bis((1H-imidazol-1-yl)methyl)benzene (BIMB). Crystal structural analysis reveals that they exhibit varied structures. Compound I contains two crystallographically unique CoII centers, each lying on an inversion center and having a slightly distorted octahedral environment. The BIMB ligands link the CoII cations to generate a three-dimensional porous framework with a 4-connected uninodal (65.8) topology. Compound II exhibits a two-dimensional sheeted metal-organic structure running parallel to the (0 0 1) plane, in which TIMB ligands join Co2+ centers having a six-coordinated octahedral structure. In the solid state, adjacent sheets are further bridged by guest SiF6- anions via C–H...F hydrogen-bonding interactions, giving rise to a three-dimensional supramolecular network structure with a 2-nodal (3-c)2(6-c) net. The topological analysis suggests that the point Schläfli symbol of compound II is (43)2(46.66.83). In addition, their thermal stabilities have also been investigated. [ABSTRACT FROM AUTHOR]

C9H6Br6, hexagonal, P63/m (no. 176), a = 8.8911(3) Å, c = 10.6847(5) Å, V = 731.48(6) Å3, Z = 2, Rgt(F) = 0.0441, wRref(F2) = 0.1094, T = 293 K. [ABSTRACT FROM AUTHOR]

C9H6Br6, hexagonal, P63/m (no. 176), a = 8.8911(3) Å, c = 10.6847(5) Å, V = 731.48(6) Å3, Z = 2, Rgt(F) = 0.0441, wRref(F2) = 0.1094, T = 293 K. [ABSTRACT FROM AUTHOR]

The one-dimensional (1D) spatial distributions of OH absolute concentration in methane/air laminar premixed flat flame under different equivalence ratios at atmospheric pressure are investigated by using bi-directional laser-induced fluorescence (LIF) detection scheme combined with the direct absorption spectroscopy. The effective peak absorption cross section and the average temperature at a height of 2 mm above the burner are obtained by exciting absorption on the Q1(8) rotational line in the A2Σ+ (ʋ′ = 0) ← X2Π (ʋ″ = 0) at 309.240 nm. The measured values are 1.86×10−15 cm2 and 1719 K, respectively. Spatial filtering and frequency filtering methods of reducing noise are used to deal with the experimental data, and the smoothing effects are also compared using the two methods. The spatial distribution regularities of OH concentration are obtained with the equivalence ratios ranging from 0.8 to 1.3. The spatial resolution of the measured result is 84 μm. Finally, a comparison is made between the experimental result of this paper and other relevant study results. [ABSTRACT FROM AUTHOR]

In this paper, three ultrashort-pulse coherent anti-Stokes Raman scattering (CARS) thermometry approaches are summarized with a theoretical time-domain model. The difference between the approaches can be attributed to variations in the input field characteristics of the time-domain model. That is, all three approaches of ultrashort-pulse (CARS) thermometry can be simulated with the unified model by only changing the input fields features. As a specific example, the hybrid femtosecond/picosecond CARS is assessed for its use in combustion flow diagnostics; thus, the examination of the input field has an impact on thermometry focuses on vibrational hybrid femtosecond/picosecond CARS. Beginning with the general model of ultrashort-pulse CARS, the spectra with different input field parameters are simulated. To analyze the temperature measurement error brought by the input field impacts, the spectra are fitted and compared to fits, with the model neglecting the influence introduced by the input fields. The results demonstrate that, however the input pulses are depicted, temperature errors still would be introduced during an experiment. With proper field characterization, however, the significance of the error can be reduced.