Multilayer-shaped compression and slide models were employed to investigate the complex sensitive mechanisms of cocrystal explosives in response to external mechanical stimuli. Here, density functional theory (DFT) calculations implementing the generalized gradient approximation (GGA) of Perdew-Burke-Ernzerhof (PBE) with the Tkatchenko-Scheffler (TS) dispersion correction were applied to a series of cocrystal explosives: diacetone diperoxide (DADP)/1,3,5-trichloro-2,4,6-trinitrobenzene (TCTNB), DADP/1,3,5-tribromo-2,4,6-trinitrobenzene (TBTNB) and DADP/1,3,5-triiodo-2,4,6-trinitrobenzene (TITNB). The results show that the GGA-PBE-TS method is suitable for calculating these cocrystal systems. Compression and slide models illustrate well the sensitive mechanism of layer-shaped cocrystals of DADP/TCTNB and DADP/TITNB, in accordance with the results from electrostatic potentials and free space per molecule in cocrystal lattice analyses. DADP/TCTNB and DADP/TBTNB prefer sliding along a diagonal direction on the a?c face and generating strong intermolecular repulsions, compared to DADP/TITNB, which slides parallel to the b?c face. The impact sensitivity of DADP/TBTNB is predicted to be the same as that of DADP/TCTNB, and the impact sensitivity of DADP/TBTNB may be slightly more insensitive than that of DADP and much more sensitive than that of TBTNB.
Ultra-high-pressure liquid chromatography (UHPLC) was coupled with linear ion trap quadrupole Orbitrap mass spectrometry (LTQ-Orbitrap) and was used for the first time to systematically analyze the absorbed components and metabolites in rat plasma after oral administration of the water extract of Sarcandra glabra. This extract is a well-known Chinese herbal medicine for the treatment of inflammation and immunity related diseases. The anti-inflammatory activities of the absorbed components were evaluated by measuring nitric oxide (NO) production and proinflammatory genes expression in lipopolysaccharide (LPS)-stimulated murine RAW 264.7 macrophages. As a result, 54 components in Sarcandra glabra were detected in dosed rat plasma, and 36 of them were positively identified. Moreover, 23 metabolites were characterized and their originations were traced. Furthermore, 20 of the 24 studied components showed anti-inflammatory activities. These results provide evidence that this method efficiency detected constituents in plasma based on the anti-inflammatory mechanism of multiple components and would be a useful technique for screening multiple targets for natural medicine research. 相似文献
<正>B and T lymphocytes are responsible for the acquisition of adaptive immune response, among which, B cells dominate humoral immunity. In vivo, B cells utilize surface expressed B cell receptors (BCRs) to sense antigens presented by antigen-presenting cells (APCs), and eventually mediate antibody response and immune memory. It is well recognized 相似文献
