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•Rod-shaped cell harvesting by cross-flow microfiltration with static mixer is investigated.•Radial mixing hindered the shear-induced arrangement of Bacillus velezensis cells.•Flux ...improvement up to 300% was achieved and it coincides with reduction in specific energy consumption.•Bacillus velezensis cells retained viability.•Microfiltration parameters were optimized using RSM and GA.
Substitution of synthetic agrochemicals with bio pesticides, due to the hazards of pollution, has put attention on the development of cost-effective solutions for their production. Membrane fouling remains an immense problem for cross-flow microfiltration implementation in bio-control agent production. The shear-induced arrangement of rod-shaped bacterial cells results in the creation of the brick-like wall layer in filtration cake that has denser packing, and a higher tortuosity, which leads to higher cake resistance. From this perspective, applying turbulent flow by increasing cross-flow velocity is a possible method for the reduction of cake resistance, controlling the filtration performance, which in turn results in higher energy consumption. Turbulence promoters can be positioned into a channel of tubular membranes to reduce cake resistance and consequently increase permeation flux. Radial mixing caused by the turbulence promoter has contributed to disturbance of the shear-induced arrangement of cells and the flux improvement was in the range between 50% to approximately 300%, depending on experimental conditions. Static mixer i.e. turbulence promoter caused higher permeate fluxes at same specific energy consumption, without loss of cell viability due to an increase in shear rate. Microfiltration parameters were optimized using response surface methodology and genetic algorithm.
We present the first determination of the energy-dependent amplitudes of N⁎ resonances extracted from their decay in KΛ pairs in p+p→pK+Λ reactions. A combined Partial Wave Analysis of seven data ...samples with exclusively reconstructed p+p→pK+Λ events measured by the COSY-TOF, DISTO, FOPI and HADES Collaborations in fixed target experiments at kinetic energies between 2.14 to 3.5 GeV is used to determine the amplitude of the resonant and non-resonant contributions into the associated strangeness final state. The contribution of seven N⁎ resonances with masses between 1650 MeV/c2 and 1900 MeV/c2 for an excess energy between 0 and 600 MeV has been considered. The Σ–p cusp and final state interactions for the p–Λ channel are also included as coherent contributions in the PWA. The N⁎ contribution is found to be dominant with respect to the phase space emission of the pKΛ+ final state at all energies demonstrating the important role played by both N⁎ and interference effects in hadron–hadron collisions.
We present measurements of the excitation function of elliptic flow at midrapidity in Au+Au collisions at beam energies from 0.09 to 1.49 GeV per nucleon. For the integral flow, we discuss the ...interplay between collective expansion and spectator shadowing for three centrality classes. A complete excitation function of transverse momentum dependence of elliptic flow is presented for the first time in this energy range, revealing a rapid change with incident energy below 0.4 AGeV, followed by an almost perfect scaling at the higher energies. The equation of state of compressed nuclear matter is addressed through comparisons to microscopic transport model calculations.
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The production of K
+
, K
-
and
(1020) mesons is studied in Al+Al collisions at a beam energy of 1.9A GeV which is close to or below the production threshold in NN reactions. Inverse slopes, ...anisotropy parameters, and total emission yields of K
±
mesons are obtained. A comparison of the ratio of kinetic energy distributions of K
-
and K
+
mesons to the HSD transport model calculations suggests that the inclusion of the in-medium modifications of kaon properties is necessary to reproduce the ratio. The inverse slope and total yield of
mesons are deduced. The contribution to K
-
production from
meson decays is found to be
%. The results are in line with the previous K
±
and
data obtained for different colliding systems at similar incident beam energies.
We present a complete systematics (excitation functions and system-size dependences) of global stopping and side flow for heavy ion reactions in the energy range between 0.09A and 1.93A GeV. For the ...heaviest system, Au+Au, we observe a plateau of maximal stopping extending from about 0.2A to 0.8A GeV with a fast drop on both sides. The degree of stopping, which is shown to remain significantly below the expectations of a full stopping scenario, is found to be highly correlated to the amount of side flow.
SiΛvio: A trigger for Λ-hyperons Münzer, Robert; Berger, Martin; Fabbietti, Laura ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
05/2014, Letnik:
745
Journal Article
Recenzirano
Odprti dostop
As online trigger for events containing Λ hyperons in p+p collisions at 3.1GeV a silicon-based device has been designed and built. This system has been integrated close to the target region within ...the FOPI spectrometer at GSI and was also employed as a tracking device to improve the vertex reconstruction of secondary decays. The design of the detector components, read-out, the trigger capability as well as the tracking performance are presented. An enrichment factor of about 14 was achieved for events containing a Λ-hyperon candidate.
Detailed studies of the azimuthal dependence of the mean fragment and flow energies in the Au+Au and Xe+CsI systems are reported as a function of incident energy and centrality. Comparisons between ...data and model calculations show that the flow energy values along different azimuthal directions could be viewed as snapshots of the fireball expansion with different exposure times. For the same number of participating nucleons more transversally elongated participant shapes from the heavier system produce less collective transverse energy. Good agreement with Boltzmann-Uehling-Uhlenbeck calculations is obtained for a soft nuclear equation of state.
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