Biodiesel as a Plasticizer of a SBR-Based Tire Tread Formulation

The solubility parameter of a series of methyl esters of fatty acids, the components of biodiesel, was calculated using the group incremental method proposed by Van Krevelen. The solubility parameter of biodiesel was compared with that of a series of rubbers like EPDM, butyl rubber, polyisoprene, polybutadiene, SBR (with different content of styrene), and nitrile rubber (with different content of acrylonitrile) showing that biodiesel is an effective solvent of all the above mentioned rubbers with the exclusion of nitrile rubber. Indeed, it was experimentally verified that polyisoprene, polybutadiene and SBR are easily soluble in biodiesel while polystyrene gives a cloudy solution. Considerations on the solubility parameter of the biodiesel and of a series of rubbers have led to the conclusion that biodiesel behaves essentially as an internal lubricant in a diene rubber matrix, the same situation occurs with the common aromatic mineral oil plasticizer known as T-RAE. The experimental evaluation of biodiesel as plasticizer in an SBR-based rubber compound in comparison to an aromatic mineral oil have led to the primary conclusion that biodiesel is reactive with the sulphur curing agent subtracting sulphur to the crosslinking polymer chains and leading to a vulcanizatewith lower moduli, tensile and hardness and higher elongationsin comparison to a reference compound fully plasticized with an aromatic mineral oil. However, biodiesel seems a good low temperature plasticizer because the low elastic modulus observed is desired in a winter tire tread for a good grip on snow and ice. The present work is only an exploratory work, and the tire tread formulation with biodiesel was not optimized

Isotope Exchange in Disulfur Monoxide-Water Charged Complexes: A Mass Spectrometric and Computational Study

A hitherto unknown, isotope-exchange reaction is studied in ionized gaseous mixtures containing disulfur monoxide and water. The kinetics, mechanism, and intermediate of the reaction are investigated by experimental and theoretical methods. The reactivity of the S2O˙+ cation with water is investigated under a wide range of pressures ranging from 10−7 to 10−4 Torr, by FT-ICR, TQ, and high-resolution CAD mass spectrometry. In the high-pressure limit the reaction proves to be a route to strongly bound sulfur-containing species

Evaluation of the Biodegradable Peripheral Igaki-Tamai Stent in the Treatment of De Novo Lesions in the Superficial Femoral Artery

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De la lectura a la creación en la red: el tráiler de lectura

El artículo describe y reflexiona sobre las competencias lectoras que tiene que desarrollar un adolescente en un entorno digital. El foco se pone en cómo el entorno digital transforma al lector en un creador de contenidos y en las acciones que se pueden realizar para conseguirlo de manera diversificada, lingüística y culturalmente. La primera parte del estudio desarrolla el concepto de competencia lectora digital: las destrezas que debe desarrollar, los tipos de textos que Internet le propone y las dificultades con las que se encuentra. La segunda parte analiza los resultados de tres estudios de casos en los que la lectura se transforma en creación a través del tráiler de lectura (se trata de concursos realizados en catalán, desde un centro educativo, la biblioteca y la institución pública) y en las acciones de políticas públicas que se proponen llevar a cabo para mejorar los resultados

The Swift X-ray flaring afterglow of GRB 050607

The unique capability of the Swift satellite to perform a prompt and autonomous slew to a newly detected Gamma-Ray Burst (GRB) has yielded the discovery of interesting new properties of GRB X-ray afterglows, such as the steep early lightcurve decay and the frequent presence of flares detected up to a few hours after the GRB trigger. We present observations of GRB 050607, the fourth case of a GRB discovered by Swift with flares superimposed on the overall fading X-ray afterglow. The flares of GRB 050607 were not symmetric as in previously reported cases, showing a very steep rise and a shallower decay, similar to the Fast Rise, Exponential Decay that are frequently observed in the gamma-ray prompt emission. The brighter flare had a flux increase by a factor of approximately 25,peaking for 30 seconds at a count rate of approximately 30 counts s-1, and it presented hints of addition short time scale activity during the decay phase. There is evidence of spectral evolution during the flares. In particular, at the onset of the flares the observed emission was harder, with a gradual softening as each flare decayed. The very short time scale and the spectral variability during the flaring activity are indicators of possible extended periods of energy emission by the GRB central engine. The flares were followed by a phase of shallow decay, during which the forward shock was being refreshed by a long-lived central engine or by shells of lower Lorentz factors, and by a steepening after approximately 12 ks to a decay slope considered typical of X-ray afterglows.Comment: 23 pages, 5 figures, Accepted by the Astrophysical Journa

Current Knowledge on Endocrine Disrupting Chemicals (EDCs) from Animal Biology to Humans, from Pregnancy to Adulthood: Highlights from a National Italian Meeting

Wildlife has often presented and suggested the effects of endocrine disrupting chemicals (EDCs). Animal studies have given us an important opportunity to understand the mechanisms of action of many chemicals on the endocrine system and on neurodevelopment and behaviour, and to evaluate the effects of doses, time and duration of exposure. Although results are sometimes conflicting because of confounding factors, epidemiological studies in humans suggest effects of EDCs on prenatal growth, thyroid function, glucose metabolism and obesity, puberty, fertility, and on carcinogenesis mainly through epigenetic mechanisms. This manuscript reviews the reports of a multidisciplinary national meeting on this topic

West Nile virus transmission. results from the integrated surveillance system in Italy, 2008 to 2015

IIn Italy a national Plan for the surveillance of imported and autochthonous human vector-borne diseases (chikungunya, dengue, Zika virus disease and West Nile virus (WNV) disease) that integrates human and veterinary (animals and vectors) surveillance, is issued and revised annually according with the observed epidemiological changes. Here we describe results of the WNV integrated veterinary and human surveillance systems in Italy from 2008 to 2015. A real time data exchange protocol is in place between the surveillance systems to rapidly identify occurrence of human and animal cases and to define and update the map of affected areas i.e. provinces during the vector activity period from June to October. WNV continues to cause severe illnesses in Italy during every transmission season, albeit cases are sporadic and the epidemiology varies by virus lineage and geographic area. The integration of surveillance activities and a multidisciplinary approach made it possible and have been fundamental in supporting implementation of and/or strengthening preventive measures aimed at reducing the risk of transmission of WNV trough blood, tissues and organ donation and to implementing further measures for vector control

A comparative study of the antimicrobial and antioxidant activities of Inonotus hispidus fruit and their mycelia extracts

Inonotus hispidus (Bull.) P. Karst. has been used as traditional medicine for the treatment of dyspepsia, cancer, and diabetes. Numerous studies have confirmed the antimicrobial, antiviral, antioxidant, anti-inflammatory, immunomodulatory, antiproliferative and cytotoxic biological activities of extracts from this species. The purpose of this study was a comparative analysis of the antioxidant and the antimicrobial activities of methanol extracts from fruit and liquid-cultured mycelia. Four compounds (N-butylbenzenesulfonamide, lauramidopropyl betaine, 3,5-di-tert-butyl-4-hydroxybenzaldehyde, and uplandicine), determined by hybrid HRMS, were found only in mycelia culture extracts. Free radical scavenging, measured by DPPH assay on methanol extracts, showed an activity of about 17.2% and 22.1% of Trolox in fruiting bodies and mycelia, respectively. The I. hispidus methanol extracts from fruit and mycelia culture were found to have varying degrees of antibacterial and antifungal effects against the pathogenic microorganisms tested (minimum inhibitory concentration from 0.17 to 2.56 μg mL−1)

Swift XRT Observations of the Afterglow of GRB 050319

Swift discovered the high redshift GRB 050319 with the Burst Alert Telescope and began observing with its narrow field instruments only 225 s after the burst onset. The afterglow X-ray emission was monitored by the XRT up to 28 days after the burst. The light curve shows a decay with three different phases, each characterized by a distinct slope: an initial steep decay with a power law index of ~ 5.5, a second phase characterized by a flat decay slope of \~ 0.54, and a third phase with a decay slope of ~ 1.14. During the first phase the spectral energy distribution is softer than in the following two phases and the photon index is consistent with the GRB prompt spectrum. The extrapolation of the BAT light curve to the XRT band suggests that the initial fast decaying phase of the XRT afterglow might be the low energy tail of the prompt emission. The second break in the afterglow light curve occurs about 27000 s after the burst. The spectral energy distribution before and after the second break does not change and it can be tentatively interpreted as a jet break or the end of a delayed or continuous energy injection phase.Comment: 15 pages, 2 figures. Accepted for publication in Ap