Abstract. The results of the optical monitoring between November 1994 and November 1995 of twenty γ-ray loud blazars included in the Torino blazar monitoring program are presented. All data were taken with the 1.05 m REOSC astrometric telescope of the Torino Astronomical Observatory, equipped with a 1242 × 1152 pixels charge-coupled device (CCD) camera. Observations have been carried out in the standard B, V (Johnson), and R (Cousins) bands. Source magnitudes are calculated with respect to reference stars in the same frame. For half blazar fields it was possible to perform a photometric calibration through the observation of Landolt's fields during photometric nights. In the other cases either photometric sequences from the literature were adopted or, when lacking, magnitudes were simply normalized to their minimum value. Most of the monitored objects show a more or less pronounced brightness variability on both short and long time scales. In a few cases also noticeable intranight variations were detected. Data simultaneous to pointings of the Compton Gamma Ray Observatory (CGRO) are present in our light curves: when the γ data are available they will provide a useful information in order to understand the possible correlations between the optical and γ-ray emissions. For one source (PKS 2254+074) we performed also photopolarimetry, deducing magnitudes, amount of polarization, and position angle in the UBV RI bands.

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and in the field of biomass conversion. Future applications for CO 2 separation technologies are presumed to be within the so-called carbon capture and utilization (CCU) route. [6][7][8] The idea is to exploit CO 2 as a raw material for further chemical or industrial use and, thus, to valorize it by recycling. In the long term, CCU aims the development of a circular economy concept with neutral carbon emissions.Absorption is one of the main techniques used for CO 2 capture, [9] it relies on either chemical or physical interactions between the solvent and the solute CO 2 . In physical absorption, intermolecular forces, such as Coulomb, Van-der-Waals or other dispersion forces dominate the solute-solvent interactions. In chemical absorption, CO 2 chemically reacts with the solvent molecules and forms covalent bonds. Due to their stoichiometric reaction with CO 2 , their CO 2 absorption capacity is very high even at low CO 2 partial pressures. Chemical absorption is particularly appropriate if CO 2 is to be recovered from flue gas streams with relatively low concentrations. The major advantages of chemical absorption processes are the high selectivity for CO 2 and the high achievable gas product purity.The most commonly used chemical absorbents are amines (15-60 wt%) in aqueous solutions (i.e., typical loading of 0.5 mol CO 2 /mol amine for monoethanolamine, MEA). Amines have some drawbacks like a high corrosion rate at high concentrations, the outlet purified gas contains a high-water amount, the energy demand for their regeneration is high and they suffer from high evaporation losses. [10] Indeed, the reverse chemical reaction requires considerable activation energy that is commonly supplied by increasing the temperature of the absorbent. When a volatile absorbent is used, it must be either condensed from the purified gas stream or replenished with the consequent rise of operative costs. Therefore, improvement of the absorption medium, e.g., decreasing the volatility without losing the high loading of the absorbent phase is the primary research interest in physical and chemical absorption technologies.Since the 1990s, low-melting salts have gained increasing interest for application as alternative absorbents in a wide field of chemical processes. For salts with melting points below 100 °C, the term ionic liquid (IL) has been coined. As ILs are built up from an organic cation and an inorganic or organic anion, there is a vast variety of possible structures. Over the last years, a plethora of ILs and their mixtures have been Solutions of biobased ionic liquids (ILs) for recovering CO 2 from industrial flue gas are investigated. Four CO 2 task-specific choline-based amino acids ([Cho][AA]): Alanine, Glycine, and, for the first time, Proline and Serine are tested. The drawbacks related to the high viscosity of these ILs are limited by applying dimethyl sulfoxide (DMSO) as a solvent, which is chosen because it is a polar aprotic liquid with a low toxicity, low vapor pressure, and relatively low price. The choline-based...