Characterization of Volatile Organic Compounds (VOC) in wet-white and metal-free leathers

Content: As it is known in the tanning sector, in recent times, the so-called wet-white and/or metal-free concepts have had a certain increase. For example, in the automotive sector, the wet-white tanning system, carried out with glutaraldehyde and tannins, has been widely diffused. In fact, car manufacturers offer, for interior furnishings, leather not only for high-end cars but increasingly also in the lower segments. The components on which the leather upholstery is applied are mainly steering wheel, seats, dashboard and panels. Therefore, the use of leather also in this context must be able to meet both the aesthetic/performance criteria and the environmental ones; environmental criteria should also consider the air quality of the interior of a motor vehicle. In practice, the interior furniture consisting of finished leather must be able to release a few volatile substances and, at the same time, provide a typical smell of leather. Considering, therefore, the diffusion of alternative chrome tanning systems for the different uses, in this work, wet-white (glutaraldehyde and tannins) will be investigated, both from the point of view of the performance characteristics and from the ecotoxicological ones. and leathers deriving from the latest generation of metal-free tanning. For the characterization of Volatile Organic Compounds (VOC) the GC-MS will be used coupled with the 'Purge and Trap' technique with the aim of obtaining information on the new substances used in the wetwhite / metal free production process and then avoiding undesired effects during use (eg bad smell, SVHC substances, etc.) Take-Away: metal-free automotive VO

The CHEOPS (characterising exoplanet satellite) mission: telescope optical design, development status and main technical and programmatic challenges

CHEOPS (CHaracterising ExOPlanet Satellite) is the first ESA Small Mission as part of the ESA Cosmic Vision program 2015-2025 and it is planned launch readiness end of 2017. The mission lead is performed in a partnership between Switzerland, led by the University of Bern, and the European Space Agency with important contributions from Austria, Belgium, France, Germany, Hungary, Italy, Portugal, Spain, Sweden, and the United Kingdom. The CHEOPS mission will be the first space telescope dedicated to search for exoplanetary transits on bright stars already known to host planets by performing ultrahigh precision photometry on bright starts whose mass has been already estimated through spectroscopic surveys on ground based observations. The number of exoplanets in the mass range 1-30 MEarth for which both mass and radius are known with a good precision is extremely limited also considering the last two decades of high-precision radial velocity measurement campaigns and the highly successful space missions dedicated to exoplanets transit searches (CoRoT and Kepler)

Phase curve and geometric albedo of WASP-43b measured with CHEOPS, TESS, and HST WFC3/UVIS

Context. Observations of the phase curves and secondary eclipses of extrasolar planets provide a window onto the composition and thermal structure of the planetary atmospheres. For example, the photometric observations of secondary eclipses lead to the measurement of the planetary geometric albedo, Ag, which is an indicator of the presence of clouds in the atmosphere. Aims: In this work, we aim to measure the Ag in the optical domain of WASP-43b, a moderately irradiated giant planet with an equilibrium temperature of ~1400 K. Methods: For this purpose, we analyzed the secondary eclipse light curves collected by CHEOPS together with TESS along with observations of the system and the publicly available photometry obtained with HST WFC3/UVIS. We also analyzed the archival infrared observations of the eclipses and retrieve the thermal emission spectrum of the planet. By extrapolating the thermal spectrum to the optical bands, we corrected for the optical eclipses for thermal emission and derived the optical Ag. Results: The fit of the optical data leads to a marginal detection of the phase-curve signal, characterized by an amplitude of 160 ± 60 ppm and 80−50+60 ppm in the CHEOPS and TESS passbands, respectively, with an eastward phase shift of ~50° (1.5σ detection). The analysis of the infrared data suggests a non-inverted thermal profile and solar-like metallicity. The combination of the optical and infrared analyses allows us to derive an upper limit for the optical albedo of Ag< 0.087, with a confidence of 99.9%. Conclusions: Our analysis of the atmosphere of WASP-43b places this planet in the sample of irradiated hot Jupiters, with monotonic temperature-pressure profile and no indication of condensation of reflective clouds on the planetary dayside

The phase curve and the geometric albedo of WASP-43b measured with CHEOPS, TESS and HST WFC3/UVIS

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Covalent immobilization of chloroperoxidase on silica gel and properties of the immobilized biocatalyst

Immobilization of chloroperoxidase (CPO) isolated from the mold Caldariomyces fumago on silica gel was performed. The support was derivatized with 3-glycidoxypropyltrimethoxysilane by using a reported method and the enzyme was covalently bound via reaction with epoxide groups under mild conditions. The enzyme was still active after the immobilization process. No leaching of the enzyme from the support was detectable after repeated washings. The halogenation reaction catalysed by the immobilized enzyme in buffer was compared to that catalysed by the free enzyme. The immobilization of CPO enhanced the stability of the enzyme with respect to the effect of pH and oxidizing agent concentration

Photocatalytic treatment of industrial wastewaters using structured photocatalysts

Nowadays one of the most significant environmental problems is related to wastewater treatment because the release of pollutants into the environment has posed a risk to natural ecosystems and human health. Therefore, it is necessary to treat wastewater in appropriately way. Three main steps are applied in wastewater treatments that are commonly called preliminary, secondary and tertiary treatment. The preliminary and secondary treatment steps are based on physical and chemical processes. However, in most cases these types of processes are not enough alone. Among tertiary process treatment, compared to the common processes used for wastewater disinfection, new methods without the formation of disinfection byproducts have been recently investigated by researchers. In this sense, among advanced oxidation process (AOPs), heterogeneous photocatalysis is a powerful alternative technique to treat polluted water because it is able to mineralize many organic compounds through the generation of hydroxyl radicals thanks to the presence of a semiconductor activated by a light source. For engineering applications, the immobilization of catalyst powders onto a suitable solid inert support is required. In this work, ZnO immobilized on macroscopic polystyrene pellets has been prepared, characterized and studied in the photocatalytic treatment of four wastewaters samples coming from secondary and tertiary processes of wastewater treatment plant by leather industries. The efficiency of the system has been determined by measuring chemical oxygen demand (COD) and total organic carbon (TOC). Photocatalytic results showed in all cases a significant COD and TOC reduction, after 7 h of UV light irradiation

Inactivation studies on native and silicagel non-homogeneous immobilized chloroperoxidase

A pH stability analysis was made, in the presence of tert-butyl hydroperoxide, of both immobilized and native chloroperoxidase obtained from Caldariomyces fumago and the inactivation constants (j1) evaluated. The native enzyme displays a uni-exponential decay, whereas for the immobilized enzyme a three exponential equation describes the time dependent enzyme inactivation. For immobilized enzyme, three-exponential equation describes the enzyme time-course inactivation. The obtained inactivation constants (j3 and K3) showed an increase in the stability of a fraction of the immobilized enzyme. This is probably due to a decrease of the affinity of the enzyme for the oxidant and not to a decrease in j3 values