Microfluidic synthesis and assembly of reactive polymer beads to form new structured polymer materials

Monodisperse and size-controlled polymer particles were produced without surfactant or wash-coat from O/W monomer emulsions and ‘‘on the fly’’ polymerization under UV irradiation in a very simple needle/tubing system. The effect of the viscosity of the continuous phase on the size of final particles was investigated. The capillary number ratio was found to be relevant to predict the size of the droplets. A relation between dimensionless numbers predicts particle diameter as a function of the needle inner diameter and both velocity and viscosity ratios of continuous and dispersed phases. A functional comonomer was incorporated in the monomer phase so as to obtain polymer microparticles bearing reactive groups on their surface. Polymer beads necklaces were thus formed by linking polymer particles together

High resolution spectroscopy of the extended narrow-line region of IC 5063 and NGC 7212

We studied the properties of the gas of the extended narrow line region (ENLR) of two Seyfert 2 galaxies: IC 5063 and NGC 7212. We analysed high resolution spectra to investigate how the main properties of this region depend on the gas velocity. We divided the emission lines in velocity bins and we calculated several line ratios. Diagnostic diagrams and SUMA composite models (photo-ionization + shocks), show that in both galaxies there might be evidence of shocks significantly contributing in the gas ionization at high |V|, even though photo-ionization from the active nucleus remains the main ionization mechanism. In IC 5063 the ionization parameter depends on V and its trend might be explained assuming an hollow bi-conical shape for the ENLR, with one of the edges aligned with the galaxy disk. On the other hand, NGC 7212 does not show any kind of dependence. The models show that solar O/H relative abundances reproduce the observed spectra in all the analysed regions. They also revealed an high fragmentation of the gas clouds, suggesting that the complex kinematics observed in these two objects might be caused by interaction between the ISM and high velocity components, such as jets.Comment: 29 pages, 32 figures, accepted for publication in MNRA

Fast magnetoacoustic waves in a randomly structured solar corona

The propagation of fast magnetoacoustic waves in a randomly structured solar corona is considered in the linear and cold plasma limits. The random field is assumed to be static and associated with plasma density inhomogeneities only. A transcendental dispersion relation for the fast magnetoacoustic waves which propagate perpendicularly to the magnetic field is derived in the weak random field approximation. It is shown analytically that the fast magnetosonic waves experience acceleration, attenuation, and dispersion in comparison to the homogeneous case. These analytical findings are essentially confirmed by numerical simulations for a wide-spectrum pulse, except that the waves were found decelerated. It is concluded that the coronal Moreton waves can be applied to MHD seismology of the solar corona

X-ray flashes from the low-mass X-ray binary IGR J17407-2808

IGR J17407-2808 is an enigmatic and poorly studied X-ray binary that was recently observed quasi-simultaneously with NuSTAR and XMM-Newton. In this paper we report the results of this observational campaign. During the first 60 ks of observation, the source was caught in a relatively low emission state, characterised by a modest variability and an average flux of ~8.3E-13 erg/cm^2/s (4-60 keV). Afterwards, IGR J17407-2808 entered a significantly more active emission state that persisted for the remaining ~40 ks of the NuSTAR observation. During this state, IGR J17407-2808 displayed several fast X-ray flares, featuring durations of ~1-100 s and profiles with either single or multiple peaks. The source flux in the flaring state reached values as high as 2E-9 erg/cm^2/s (4-60 keV), leading to a measured dynamic range during the NuSTAR and XMM-Newton campaign of >~ 10^3. We also analysed available archival photometric near-infrared data of IGR J17407-2808 to improve the constraints available so far on the the nature of the donor star hosted in this system. Our analysis shows that the donor star can be either a rare K or M-type sub-subgiant or an K type main sequence star, or sub-giant star. Our findings support the classification of IGR J17407-2808 as a low-mass X-ray binary. We discuss the source X-ray behaviour as recorded by NuSTAR and XMM-Newton in view of this revised classification.Comment: Accepted for publication in Astronomy & Astrophysic

Consequential-based life cycle assessment of reducing the concentrates supply level in the diet fed to lactating cows in the alpine dairy farming system

This study aimed to assess the consequences of reducing the concentrates supply level (CSL) in the lactating cows’ diet on Alpine dairy system’s GHG emissions. Consequential-based Life Cycle Assessment (cLCA) was adopted to assess the consequences within the ‘dairy_system’ (farm plus milk processing) and outside (‘expanded_system’). The functional unit was 1 kg of protein and fat (ProtFat). Data (1-year average) originated from 40 dairy farms in the Alps, collected through farm questionnaires during farm visits. Emissions were evaluated without (GWP) and with land-based emissions (crop- (GWP_LULUC_cb) or global-based (GWP_LULUC_gb) method). The feed conversion ratio was computed in terms of potentially human-edible gross energy (HeECR, MJ feed/MJ milk). Three scenarios were explored: 100% (t0), 75% (t175), and 50% (t150) of the initial CSL. Impact values for both systems were analysed with a mixed model to test the effect of the scenarios. At ‘dairy_system’, 1 kg ProtFat caused 19.0 (GWP), 22.9 (GWP_LULUC_cb) and 23.4 kg CO2-eq (GWP_LULUC_gb) at t0 and HeECR resulted in 0.71 MJ feed/MJ milk. The CSL reduction from t0 to t175 and t150 significantly increased impact values (2–11%) and decreased HeECR (from −10 to −23%). Considering ‘expanded_system’, CSL reduction significantly increased GWP (4%) and GWP_LULUC_gb (3%) but decreased GWP_LULUC_cb (up to −4%). In conclusion, cLCA-based approach evidenced that CSL reductions implied diversified effects on GHG emissions, at Alpine dairy system and at food supply level, giving new insights into the challenge of reducing GHG emissions while favouring the decoupling of milk production from the use of human-edible resources.Highlights Consequential Life Cycle Assessment of reducing concentrates supply (CSL) to lactating cows on the GHG emission of Alpine dairy products was analysed GHGs per protein plus fat in the product increased with decreasing CSL (75% and 50% of initial CSL) but can decrease considering land-use change GHG Decoupling Alpine dairy production from concentrates could be environmentally challenging but feasible

Cana-de-açúcar cultivada em solo adubado com lodo de esgoto: nutrientes, metais pesados e produtividade.

A pesquisa objetivou avaliar o uso de lodo de esgoto (Le) na adubação de soqueira (2o corte) de cana-de-açúcar (Saccharum spp., var. RB72-454). Aplicou-se Le ao solo, localizando-o no fundo de um sulco com 15 cm de profundidade e distando 40 cm da linha de cana. Avaliaram-se os efeitos das doses do Le (0, 15 e 30 t.ha-1) nas produtividades de biomassa e de açúcar, nos teores de nutrientes e de metais pesados do solo e da planta. O Le diminuiu a acidez potencial (H + Al) do solo e forneceu nutrientes para a cana-de-açúcar, principalmente P, S, Ca, Cu e Zn, o que refletiu em aumentos de produtividades de colmos e de açúcar por hectare. O Le causou aumentos de exportações de P, S, Ca, Cu, K, Mg e Ni pela parte aérea da cana-de-açúcar; tais aumentos, por sua vez, foram motivados pelos aumentos dos teores destes elementos no tecido vegetal, e da produtividade em biomassa. Os metais pesados (Cd, Cr, Ni e Pb), contidos no Le, não apresentaram perigo à cadeia trófica à curto prazo

Exploring the parent population of beamed NLS1s: from the black hole to the jet

The aim of this work is to understand the nature of the parent population of beamed narrow-line Seyfert 1 galaxies (NLS1s), by studying the physical properties of three parent candidates samples: steep-spectrum radio-loud NLS1s, radio-quiet NLS1s and disk-hosted radio-galaxies. In particular, we focused on the black hole mass and Eddington ratio distribution and on the interactions between the jet and the narrow-line region.Comment: 6 pages, 2 figures, to appear in Proceedings of High Energy Phenomena in Relativistic Outflows (HEPRO) V, Workshop Series of the Argentinian Astronomical Societ

Near-infrared morphologies of the host galaxies of narrow-line Seyfert 1 galaxies

We present J-band near-infrared (NIR) imaging of the host galaxies of nine narrow-line Seyfert 1 galaxies (NLS1). Based on highfrequency radio observations at 37 GHz, seven of them could host powerful jets that are most likely relativistic. Host galaxy morphology studies of NLS1 galaxies are scarce, but exceedingly important for understanding the seemingly heterogeneous nature of the NLS1 population as well as their evolution and place in the active galactic nuclei (AGN) scheme. Increasing the sample size is essential for achieving statistically significant results. We determine the morphological types of the host galaxies by performing photometric decomposition of NIR images using a 2D image decomposition algorithm GALFIT. We were able to sufficiently model five of the nine host galaxies. Based on the fitting parameters, mainly the Sersic index, all five are disk-like galaxies. Sources with clearly distinguishable bulge components all have pseudo-bulges, and four out of five sources show a component resembling a bar. A surprisingly large fraction, three out of five, show signs of interaction or disturbed morphology. Our results suggest that spiral galaxies with pseudo-bulges are able to launch and maintain powerful jets. They also imply that interaction - mainly minor mergers - may have a role in initially triggering higher levels of nuclear activity in NLS1 galaxies. Furthermore, our results support the heterogeneous nature of the NLS1 class and indicate that this diversity is caused by different evolutionary stages, possibly due to mergers

Benefits of Swept and Leaned Stators for Fan Noise Reduction

An advanced high bypass ratio fan model was tested in the NASA Lewis Research Center 9 x 15-Foot Low Speed Wind Tunnel. The primary focus of this test was to quantify the acoustic benefits and aerodynamic performance of sweep and lean in stator vane design. Three stator sets were used for this test series. A conventional radial stator was tested at two rotor-stator axial spacings. Additional stator sets incorporating sweep + lean, and sweep only were also tested. The hub axial location for the swept + lean, and sweep only stators corresponded to the location of the radial stator at the upstream rotor-stator spacing, while the tip axial location of these modified stators corresponded to the radial stator axial position at the downstream position. The acoustic results show significant reductions in both rotor-stator interaction noise and broadband noise beyond what could be achieved through increased axial spacing of the conventional, radial stator. Theoretical application of these results to acoustically quantify a fictitious 2-engine aircraft and flight path suggested that about 3 Effective Perceived Noise (EPN) dB could be achieved through incorporation of these modified stators. This reduction would represent a significant portion of the 6 EPNdB noise goal of the current NASA Advanced Subsonic Technology (AST) initiative relative to that of 1992 technology levels. A secondary result of this fan test was to demonstrate the ability of an acoustic barrier wall to block aft-radiated fan noise in the wind tunnel, thus revealing the acoustic structure of the residual inlet-radiated noise. This technology should prove valuable toward better understanding inlet liner design, or wherever it is desirable to eliminate aft-radiated noise from the fan acoustic signature

Unveiling the parent population of beamed narrow-line Seyfert 1s

Narrow-line Seyfert 1 galaxies (NLS1s) are active galactic nuclei (AGN) recently identified as a new class of $\gamma$-ray sources. The high energy emission is explained by the presence of a relativistic jet observed at small angles, just like in the case of blazars. When the latter are observed at larger angles they appear as radio-galaxies, but an analogue parent population for beamed NLS1s has not yet been determined. In this work we analyze this problem by studying the physical properties of three different samples of parent sources candidates: steep-spectrum radio-loud NLS1s, radio-quiet NLS1s, and disk-hosted radio-galaxies, along with compact steep-spectrum sources. In our approach, we first derived black hole mass and Eddington ratio from the optical spectra, then we investigated the interaction between the jet and the narrow-line region from the [O III] $\lambda\lambda$4959,5007 lines. Finally, the radio luminosity function allowed us to compare their jet luminosity and hence determine the relations between the samples.Comment: 6 pages, no figures. Proceedings of the 28th Texas Symposium, Geneva, December 13-18, 201