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An excellent flame suppression effect can be achieved using a novel porous brake. To understand the flame-suppression mechanism of a porous brake, combustion using a muzzle brake is investigated. A set of internal ballistic equations is employed to provide accurate velocity and pressure for a projectile moving to the muzzle. The multispecies transport Navier–Stokes equations, which incorporate complex chemical reactions, are solved by coupling a real gas equation of state, the Soave–Redlich–Kwong model, and a detailed chemical reaction kinetic model. The development of muzzle flow with a chemical reaction is simulated, and the interaction between chemical reactions with the muzzle flow field is numerically calculated to explain the muzzle combustion mechanism with a porous brake. The underlying mechanism is analyzed in detail. The results demonstrate that, first, the gas is fully expanded in the brake, leading to a reduction in pressure and temperature at the muzzle, thereby reducing the initial flame. In addition, the shock wave weakens due to the expansion and separation process, leading to a reduction in the mixture of gas and air, ultimately resulting in a reduction in the intermediate and secondary flames. [ABSTRACT FROM AUTHOR]

To further understand a muzzle combustion mechanism in high-altitude firing, the influence of supersonic flow on a muzzle combustion phenomenon is investigated. The set of internal ballistic equations is employed, providing accurate velocity and pressure when the projectile moves to the muzzle. Multispecies transport Navier–Stokes equations with complex chemical reactions are solved by coupling a real gas equation of state, the Soave–Redlich–Kwong model, and a detailed chemical reaction kinetic model. The development of muzzle flow with chemical reaction is simulated. The interaction of chemical reactions with the muzzle flow field is obtained by numerical simulation in order to explain the muzzle combustion phenomenon of fire at supersonic flight. The mechanism of muzzle combustion influenced by supersonic incoming flow is analyzed in detail. It is demonstrated from the results that the shock wave and the expansion of the jet are restrained so that the combustion is compressed behind the projectile, at the same time generating a second region of combustion behind the muzzle under the influence of supersonic incoming flow. [ABSTRACT FROM AUTHOR]

The Ce6@CuS-Pt/PEG nanoparticles have been prepared by firstly synthesizing CuS, then decorating Pt nanozymes and PEG, and finally loading Ce6. The Ce6@CuS-Pt/PEG nanoplatform exhibited efficient nanozyme-enhanced PDT-PTT combined therapy. [Display omitted] • Ce6@CuS-Pt/PEG NPs with high thermal conversion efficiency for photothermal therapy. • Pt nanozymes assisted photodynamic therapy. • Obvious inhibition of tumor growth due to nanozyme-enhanced PDT-PTT. Multifunctional nanoagents with photodynamic therapy (PDT) and photothermal therapy (PTT) functions have shown great promise for cancer treatment, while the design and synthesis of efficient nanoagents remain a challenge. To realize nanozyme-enhanced PDT-PTT combined therapy, herein we have synthesized the Ce6@CuS-Pt/PEG nanoplatforms as a model of efficient nanoagents. Hollow CuS nanospheres with an average diameter of ∼ 200 nm are first synthesized through vulcanization using Cu 2 O as the precursor. Subsequently, CuS nanospheres are surface-decorated with Pt nanoparticles (NPs) as nanozyme via an in-situ reduction route, followed by modifying the DSPE-PEG5000 and loading the photosensitizer Chlorin e6 (Ce6). The obtained Ce6@CuS-Pt/PEG NPs exhibit high photothermal conversion efficiency (43.08%), good singlet oxygen (1O 2) generation ability, and good physiological stability. In addition, Ce6@CuS-Pt/PEG NPs show good catalytic performance due to the presence of Pt nanozyme, which can effectively convert H 2 O 2 to O 2 and significantly enhance the production of cytotoxic 1O 2. When Ce6@CuS-Pt/PEG NPs dispersion is injected into mice, the tumors can be wholly suppressed owing to nanozyme-enhanced PDT-PTT combined therapy, providing better therapeutic effects compared to single-mode phototherapy. Thus, the present Ce6@CuS-Pt/PEG NPs can act as an efficient multifunctional nanoplatform for tumor therapy. [ABSTRACT FROM AUTHOR]

The mathematical and physical models of the underwater submerged gun are established to study the flow field distribution characteristics of the gun muzzle at different water depths. The Schnerr–Sauer cavitation model and the realizable k–ω transport turbulence model based on the Reynolds-averaged Navier–Stokes method are employed. The muzzle flow field for the 12.7 mm gun that is submerged launched underwater is numerically simulated by combining user-defined functions and overlapping mesh technology. The flow characteristics of the density, velocity, and pressure fields at the gun muzzle at different water depths are analyzed in detail. The results show that the muzzle flow morphology depends mainly on the pressure at different water depths. The muzzle flow field distribution in deep water is more flat due to the high value of water pressure, which limits the expansion of the muzzle gas, and the range of the velocity field of the muzzle flow field at 100 m is one time smaller than that at 1 m. [ABSTRACT FROM AUTHOR]

Allergic reactions to peanut proteins are a worldwide concern. Ara h 2 in peanut (PN) is one of the most important peanut allergens ( Koppelman, Wensing, Ertmann, Knulst, & Knol, 2004 ), which is recognized by serum immunoglobulin E (IgE) from more than 90% of peanut-allergic individuals studied by Stanley et al., 1997 . Therefore, this study aimed at determining whether high pressure and thermal treatment could reduce the allergic properties of PN. Peanut protein extracts were treated with high pressure in 100–600 MPa and/or thermal treatment in 25–75 °C for 2.5–30 min, and the immunoreactivity of PN were analyzed by competitive inhibition enzyme-linked immunosorbent assays using pool sera from eight patients with peanut specific IgE. Compared to the boiling treatment, a significant reduction in IgE binding was observed when the samples were treated at 55 °C, 600 MPa for more than 10 min. Furthermore, in a BALB/c mouse model of allergy, significant reductions in specific IgE titers were observed in PN treated with high pressure and thermal (PNH) fed mice, accompanied by reduced histamine levels in serum. Similarly, real-time reverse transcription polymerase chain reaction revealed the decrease in mRNAs encoding interferon-γ, interleukin (IL)-4 and IL-10 in ileum tissues. PNH had almost no allergenicity in the BALB/c mouse model of PN allergy. Industrial relevance High hydrostatic pressure (HHP) processing can inactivate microorganisms and enzymes, leaving sensory and nutritional quality almost unchanged. Furthermore, HHP could alter allergen conformation and hence decrease allergenic activity in rice, fish, milk and celery that were reported. As a health concern, peanut allergies have been studied in this work. We determined whether high pressure and thermal could reduce the allergic properties of peanut allergen Ara h 2. In addition, effects of high pressure and thermal treatment on the peanut allergenicity of Ara h 2 (PNH) were characterized using a BALB/c mouse model of allergy. [ABSTRACT FROM AUTHOR]