Theoretical low-energy design of exploding foil initiator

In order to promote the development of miniaturization, low-energy and integration of exploding foil initiator, its low-energy design, preparation and tests were studied. It is expected to control the initiation voltage less than 1000 V. Based on the mechanism of bridge electrical explosion and driving flyer, the performance of exploding foil initiator at different parameters of bridge, flyer and barrel was calculated, which indicates an optimal matching relationship among component parameters as the bridge size of 0.2×0.2×0.006 mm, the flyer thickness of 12~22 μm and the barrel hole size of Ф 0.3×200~350 μm

Direct Precipitation Method of Nano-CuO

Different reaction conditions were studied through orthogonal experiment and single factor experiment. Using Cu(NO3)2 as the reactant, water-alcohol solution (H2O:CH2CH3OH was 3:1) as solvent at 20°C and reaction for 45min could get nano-CuO with good dispersion and uniform size. Different kinds of characterization method were used to characterize the resultant. The average diameter of nano-CuO was 20.38nm after calculated using some relevant formula, the surface area was about 21.988 m2/g, the pore diameter was about 3.079 nm and the pore volume was 1.349×10-1 cc/g . So the method is a feasible, low cost way to industry.

Study on the Effect of Nanoporous Copper Particle Size on Copper-Based Azide

Preparing copper-based azide by in situ reaction is well-suited for MEMS processing technology and holds promising prospects in the field of MEMS micro-initiators. This study involved the preparation of porous copper with particle sizes of approximately 30 nm, 60 nm and 100 nm through powder sintering. These were used as precursors for a gas–solid in situ azide reaction to produce copper-based azide with varying morphologies and compositions. Copper-based azide micro-initiators were designed, and their output performance was evaluated using CL-20 and HNS-IV explosives. Analytical results revealed that the product from the reaction of the 100 nm precursor exhibited a lumpy and uneven structure with a conversion rate of 90.36%. The product from the 60 nm precursor reaction had a dense surface with a conversion rate of 94.56%, while the 30 nm precursor resulted in a needle-like form with a conversion rate of 92.82%. Detonation experiments demonstrated that the copper-based azide micro-initiators prepared with 100 nm of a porous copper precursor exhibited unstable output performance, requiring a 1.6 mg charge to successfully detonate CL-20 explosives. On the other hand, copper-based azide micro-initiators prepared from 60 nm and 30 nm of porous copper precursors exhibited stable output performance. A charge of 0.8 mg was adequate for reliably and consistently detonating CL-20 and HNS-IV explosives. The reduced particle size of the precursor enhanced the output performance of the copper-based azide micro-initiators, providing increased energy redundancy during detonation and improving overall usage reliability

Synthesis and Biological Evaluation of Fangchinoline Derivatives as Anti-Inflammatory Agents through Inactivation of Inflammasome

Twenty eight 7-substitued fangchinoline analogues, of which twenty two were novel, were synthesized and evaluated for their effect to inhibit lipopolysaccharide/nigericin (LPS/NIG)-induced IL-1β release at both cell and protein levels at the concentration of 5 μM. Among them, compound 6 exhibited promising inhibitory potency against IL-β activation with an IC50 value of 3.7 μM. Preliminary mechanism study revealed that 6 might target NLRP3 protein, and then block ASC pyroptosome formation with-NLRP3, rather than acting on the activation of the NLRP3 inflammasome (NF-κB and MAPK pathways) or caspase-1 protein. Our current study supported the potential role of compound 6 against IL-β activation, and provided powerful information for developing fangchinoline derivatives into a novel class of anti-inflammatory agents

A DFT Study Toward the Reaction Mechanisms of TNT With Hydroxyl Radicals for Advanced Oxidation Processes

The degradation pathway of environmental contaminant 2,4,6-trinitrotoluene (TNT) was investigated computationally at the SMD­(Pauling)/M06-2<i>X</i>/6-311+G­(d,p) level of theory. The dominant decomposition pathway of TNT → 4,6-dinitro-<i>o</i>-cresol → 4,6-dinitro-2-hydroxybenzylalcohol → 4,6-dinitro-2-hydroxybenzaldehyde was provided, and the corresponding predicted products and their distributions are in a good agreement with available experimental data on TNT degradation by Fenton reaction. It was shown that the mechanism of addition–elimination is crucial for this stage of the reaction. The reaction of H atom abstraction is a minor competing pathway. The details on transition states, intermediate radicals, and free energy surfaces for all proposed reactions are given and make up for a lack of experimental knowledge

Synthesis and Structure–Activity Relationship of Palmatine Derivatives as a Novel Class of Antibacterial Agents against Helicobacter pylori

Taking palmatine (PMT) as the lead, 20 new PMT derivatives were synthesized and examined for their antibacterial activities against six tested metronidazole (MTZ)-resistant Helicobacter pylori (H. pylori) strains. The structure&ndash;activity relationship (SAR) indicated that the introduction of a suitable secondary amine substituent at the 9-position might be beneficial for potency. Among them, compound 1c exhibited the most potent activities against MTZ-resistant strains, with minimum inhibitory concentration (MIC) values of 4&ndash;16 &mu;g/mL, better than that of the lead. It also exhibited a good safety profile with a half-lethal dose (LD50) of over 1000 mg/kg. Meanwhile, 1c might exert its antimicrobial activity through targeting H. pylori urease. These results suggested that PMT derivatives might be a new family of anti-H. pylori components