944 research outputs found

    Self-similar solutions of the G-equation - analytic description of the flame surface

    Full text link
    The main feature of the flame kinematics can be desribed with the G-equation. We investigate the solutions of the G-equation with the well-known self-similar Ansatz. The results are discussed and the method how to get self-similar solutions is briefly mentioned.Comment: just a short paper 5 pages, 5 figure

    Self-similar shock wave solutions of the non-linear Maxwell equations

    Full text link
    In our study we consider nonlinear, power-law field-dependent electrical permitivity and magnetic permeability and investigate the time-dependent Maxwell equations with the self-similar Ansatz. This is a first-order hyperbolic PDE system which can conserve non-continuous initial conditions describing electromagnetic shock-waves. Besides shock-waves other interesting solutions (e.g. with localized compact support) can be found with delicate physical properties. Such phenomena may happen in complex materials induced by the planned powerful Extreme Light Infrastructure(ELI) laser pulses.Comment: 6 pages, 2 figures published in Laser Phys. 24 (2014) 08600

    Laser assisted proton collision on light nuclei at moderate energies

    Full text link
    We present analytic angular differential cross section model for laser assisted proton nucleon scattering on a Woods-Saxon optical potential where the nth-order photon absorption is taken into account simultaneously. As a physical example we calculate cross sections for proton - 12^{12}C collision at 49 MeV in the laboratory frame where the laser intensity is in the range of 1071021 10^{7} - 10^{21} W/cm2^2 at optical frequencies. The upper intensity limit is slightly below the relativistic regime.Comment: 6 pages, 4 figures, will be submitted to Phys. Rev.

    Analytic self-similar solutions of the Oberbeck-Boussinesq equations

    Get PDF
    In this article we will present pure two-dimensional analytic solutions for the coupled non-compressible Newtoniain Navier-Stokes --- with Boussinesq approximation --- and the heat conduction equation. The system was investigated from E.N. Lorenz half a century ago with Fourier series and pioneered the way to the paradigm of chaos. We present a novel analysis of the same system where the key idea is the two-dimensional generalization of the well-known self-similar Ansatz of Barenblatt which will be interpreted in a geometrical way. The results, the pressure, temperature and velocity fields are all analytic and can be expressed with the help of the error functions. The temperature field has a strongly damped oscillating behavior which is an interesting feature.Comment: 13 pages, 4 figure

    Proton scattering on carbon nuclei in bichromatic laser field at moderate energies

    Get PDF
    We present the general theory for proton nuclei scattering in a bichromatic laser field. As a physical example we consider proton collision on carbon twelve at 49 MeV/amu moderate energies in the field of a titan sapphire laser with its second harmonic.Comment: 6 pages 5 figures, submitted to NIMB. arXiv admin note: text overlap with arXiv:1406.631

    Analytic solutions of a two-fluid hydrodynamic model

    Get PDF
    We investigate a one dimensional flow described with the non-compressible coupled Euler and non-compressible Navier-Stokes equations in Cartesian coordinate systems. We couple the two fluids through the continuity equation where different void fractions can be considered. The well-known self-similar Ansatz was applied and analytic solutions were derived for both velocity and pressure field as well. The solutions can be expressed with the error functions.Comment: 11 pages, 4 figure

    Staurosporine induces necroptotic cell death under caspase-compromised conditions in U937 cells

    Get PDF
    For a long time necrosis was thought to be an uncontrolled process but evidences recently have revealed that necrosis can also occur in a regulated manner. Necroptosis, a type of programmed necrosis is defined as a death receptor-initiated process under caspase-compromised conditions. The process requires the kinase activity of receptor-interacting protein kinase 1 and 3 (RIPK1 and RIPK3) and mixed lineage kinase domain-like protein (MLKL), as a substrate of RIPK3. The further downstream events remain elusive. We applied known inhibitors to characterize the contributing enzymes in necroptosis and their effect on cell viability and different cellular functions were detected mainly by flow cytometry. Here we report that staurosporine, the classical inducer of intrinsic apoptotic pathway can induce necroptosis under caspase-compromised conditions in U937 cell line. This process could be hampered at least partially by the RIPK1 inhibitor necrotstin-1 and by the heat shock protein 90 kDa inhibitor geldanamycin. Moreover both the staurosporine-triggered and the classical death ligand-induced necroptotic pathway can be effectively arrested by a lysosomal enzyme inhibitor CA-074-OMe and the recently discovered MLKL inhibitor necrosulfonamide. We also confirmed that the enzymatic role of poly(ADP-ribose)polymerase (PARP) is dispensable in necroptosis but it contributes to membrane disruption in secondary necrosis. In conclusion, we identified a novel way of necroptosis induction that can facilitate our understanding of the molecular mechanisms of necroptosis. Our results shed light on alternative application of staurosporine, as a possible anticancer therapeutic agent. Furthermore, we showed that the CA-074-OMe has a target in the signaling pathway leading to necroptosis. Finally, we could differentiate necroptotic and secondary necrotic processes based on participation of PARP enzyme

    Improving the Technique of Scrambled Desserts Using the Food Supplement “Magnetofood”

    Get PDF
    For improving the technology of scrambled dessert products, a food supplement, based on the nanopowder of oxides of two- and trivalent iron “Magnetofood” was introduced in the recipe composition. The object of the studies is base recipes: one of mousse “Cranberry” and sambuk “Apple”. For determining technological characteristics and quality parameters, conventional standard methods were used.It has been established, that introduction of the food supplement “Magnetofood” in amount 0,1 %, 0,15 %, 0,2 % of the recipe mixture mass improves consumption properties of scrambled desserts. The mean value of the organoleptic analysis increases by (1,25±0,1) points. The density also decreases by (29±1) kg/m3 for mousses, by (26±1) kg/m3 for sambuks, and scrambling duration – by ~ 3 minutes. At storing during 24 hours at h=(90±2) %, the microbial contamination of the surface of samples decreases – QMAFAnM in 10 times, yeasts – in 2 times, molds – in 2 times.It has been established, that introduction of the supplement “Magnetofood” favors the growth of the foam-creating ability in average: by (40±2) % for mousses, by (55±3) % for sambuks. The porosity increases by (14,3±0,7) % for mousses, by (12,7±0, 6) % for sambuks. The foam structure stability of scrambled desserts improves by (14±1,1) %. The food supplement “Magnetofood” also raises the effective viscosity by (32 ±1) Pa·s for mousses and by (41±2) Pa·s for sambuks and the mechanical strength of scrambled desserts in 1,23 times.The highest parameters were inherited to mousses and sambuks with supplement “Magnetofood” mass share 0,15 %.There have been experimentally substantiated scrambling technological parameters and regimes of recipe mixtures of berry-fruit mousses and sambuks, modified by the food supplement “Magnetofood”. The total scrambling duration is (14–16) minutes. The initial scrambling speed of the berry-fruit base is (2,0–2,2) s-1, at that the scrambling time is (5–6)·60s. Then the recipe mixture is scrambled at speed (3,3–3,5) s-1 during (3–4)·60s. Scrambling is finished at speed (2,0–2,2) s-1. The distinctive feature of the improved technology is premixing of the food supplement “Magnetofood” with gelatin, realized before the technological operation of soaking gelatin in cold water.The obtained experimental data may be used at developing innovative technologies of scrambled dessert products with the food supplement “Magnetofood”
    corecore