Aluminized explosives are widely used in military applications. However, the easy agglomeration of aluminum (Al) powder and its high ignition temperature greatly hinder reaction nano (n-Al) process explosion, thus affecting combustion explosion aluminum-containing explosives. In present study, copper (Cu) coated n-Al composite particles were introduced into aluminized explosives, Cu ball-milled octogen (HMX) energetic microspheres prepared via droplet microfluidic technology using binder....

Polymer bonded explosives (PBXs) have high energy density, excellent mechanical properties and better thermal stability. In this study, droplet microfluidic technology was used to successfully prepare HMX/TATB microspheres. The effects of different binder types concentrations on the morphology microspheres were studied, results proved that NC/GAP (1:4) provides particles a regular spherical good dispersion. Subsequently, influence concentration dispersed phase flow rate continuous particle...

In order to improve the energy output consistency of 3, 3′-diamino-4, 4′-azoxyfurazan (DAAF) in new insensitive booster and safety efficiency preparation process, a continuous system DAAF from synthesis spherical coating was designed established this paper, which combined ultrasonic micromixing reaction with microdroplet globular template. rapid stage, microfluidic mixing technology used synergistically strengthen uniform mass transfer between raw materials ensure uniformity particle...

The aggregation of nano-aluminum powder seriously hinders the energy release aluminized explosives. This study developed a strategy using droplet microfluidic technology to prepare HMX/15 ​wt% n-Al/2 (NC and F2604) high-energy microspheres systematically studied effects different binders on morphology (i.e., roundness) dispersion properties microspheres. Moreover, it investigated thermal decomposition, mechanical sensitivity, combustion performance TG, differential scanning calorimetry...

Hydrophobically modified polyelectrolytes (HMPEs) have been widely used in numerous industries as rheology modifiers because of their unique solution microstructures and fascinating viscosifying ability; however, the net contribution hydrophobic association to thickening power these structured fluids remains ambiguous due lack comparable HMPEs unmodified parent (PEs). In this work, a series model with different hydrophobe content length blocks copolymer (NH) were prepared by micellar...

Luminescence imaging in the second near-infrared (NIR-II) window (1000-1700 nm) has attracted extensive attention recent years owing to its superior tissue penetration ability and weak spontaneous fluorescence effects biological tissues. However, an important bottleneck restricting development of NIR-II luminescence technology is lack nanoprobes with suitable morphology, particle size high intensity. In this work, emitted LaF3:Er3+ nanoparticles (NPs) were synthesized by a simple chemical...

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We examined the agglomeration behavior of a suspension SiO2 nanoparticles with average dimensions ∼15 nm in solution tetrahydrofuran and polydisperse poly(methyl methacrylate) (PMMA) weight-average molecular weight range (0.3–31) × 104. For PMMA critical (Mc) ∼3 104 or larger, at which chains show effective entanglement, polymer concentration (C*) was clearly observed. At C*, dispersed came into contact one another rapidly agglomerated. C* increased decreasing weight. However, no clear...

Abstract To investigate the effect of addition poly (vinylidene fluoride) (PVDF) on nanothermites, Al/MoO 3 /PVDF energetic nanocomposites were prepared using electrospraying method. As a control group, was also designed. Then, both samples tested by FE-SEM, XRD and TG-DSC. TG-DSC results showed that released more than 934.0 J g −1 with two obvious exothermic peaks. Compared group 800.7 heat, it changed thermal performance to some extent. There Mo 2 C among residues products after reaction...

A novel composite comprising polypropylene (PP) and poly(methyl methacrylate) (PMMA) was prepared using supercritical carbon dioxide (scCO2), although the two polymers are usually immiscible have phase-separated morphology. This paper reports in detail preparation, microstructure, crystallinity, thermodynamic mechanical properties of PP/PMMA composite. The microstructure investigated transmission electron microscopy (TEM), atomic force (AFM), small-angle X-ray scattering (SAXS), these...

Poly (lactic) acid (PLA)/poly (caprolactone) (PCL) blends nanofibers, with mean diameter about 600nm, were prepared by electrospinning. This research focused on the morphological and thermal properties of nanofibers made from PLA/PCL bends different PCL content. The results showed that addition could improve morphology nanofibers. film blend fiber at ratio 80:20 is characterized smoothest surface highest orientation. distribution fibers wider than pure PLA. glass-transition temperature PLA...

To study the influence of tubular shell materials on combustion thermite, numerical simulations and experimental comparisons efficiencies thermite with PVC stainless-steel were carried out. The thermal conductivity coefficient heat radiation correlation a material directly affect transfer during heat-transfer process, that is, lower higher reflectance coefficient, flux through less is lost. results show compared tube material, temperature distribution more concentrated effect melting steel...

Abstract To study the effect of addition potassium perchlorate (KClO 4 ) on performance nano thermites, Al/Bi 2 O 3 thermites with different mass fraction (wt%) KClO was made by ultrasonic dispersion method. Then, all samples were tested SEM, DSC and rapid excitation ignition. results showed /10 wt%KClO had highest heat release. Compared , release increased 28.32%. The activation energy calculations /30 lowest (Ea). Its reduced 30%, mere about 149.17 KJ mol −1 . Finally, it can be seen from...

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<title>Abstract</title> This study investigates the fully discrete mixed finite element approximation for Navier-Stokes equations,incorporating Caputo fractional derivative with an order $\alpha\in(0,1)$.For spatial discretization of time-fractional equations,the Taylor-Hood method is utilized.In temporal direction, both L1 scheme and fast are employed under nonuniform meshes.The stability convergence these schemes established,evaluating velocity field in $L^2$-norm $H^1$-norm,and pressure...

Electrochromic smart windows can realize intelligent photothermal regulation by applying a low potential, which is of great significance for energy-saving buildings and carbon emission reduction. However, the dense structure...

Abstract In order to investigate the thermochemical and reactive properties of thermite composed typical manganese oxides, three common oxides meaning MnO 2 , Mn O 3 4 are selected in this paper form aluminothermic agent with Al powder, respectively. According chemical thermodynamics, difference Gibbs free energy among different components is calculated, reaction rate k calculated according Eyring equation, then values at ambient temperatures drawn. Furthermore, theory calorific value...

To solve the boundary integral equations (BIE) of mixed conditions, we propose mechanical quadrature methods (MQM) using specific rule to deal with weakly singular integrals. Denote $h_{m}$ as mesh width a curved edge $\Gamma_{m}$ ($m=1,...,d)$ polygons. Then multivariate asymptotic expansions solution errors are found be $O(h^{3}),$ where $h=\max_{1\leq m\leq d}h_{m}.$ Hence, by splitting extrapolation (SEM), high convergence rates $O(h^{5})$ can achieved. Moreover, numerical examples...