A versatile modular plant for converting biogas into advanced biofuels

The patented technology is a novel, portable, non-invasive, and flexible technical solution for converting biogas into valuable chemical compounds, such as bio-methanol and bio-dimethyl ether (bio-DME). It consists of compact modules, connected through a flange-valve-flange system, to be installed downstream of an existing traditional biogas plant. The two main sections of the module are those of reforming and synthesis: in the first, the biogas is converted into bio-syngas (H2/CO/CO2), while in the second the bio-syngas is transformed into advanced biofuels such as bio-methanol and bio-DME. Parts of the synthesis module can permanently be changed with small investments to switch the final products, according to local market needs and price volatilities. Downstream at the synthesis section, it is possible to add a module for separating and purifying the chemical products. The technology has been validated at the 0.15 MWe industrial scale

Impact of Charge-Resonance Excitations on CT-Mediated J-Type Aggregation in Singlet and Triplet Exciton States of Perylene Di-Imide Aggregates: A TDDFT Investigation

The modulation of intermolecular interactions upon aggregation induces changes in excited state properties of organic molecules that can be detrimental for some optoelectronic applications but can be exploited for others. The time-dependent density functional theory (TDDFT) is a cost-effective approach to determining the exciton states of molecular aggregates, and it has been shown to provide reliable results when coupled with the appropriate choice of the functional. Here we apply a general procedure to analyze the aggregates’ exciton states derived from TDDFT calculations in terms of diabatic states chosen to coincide with local (LE) and charge-transfer (CT) excitations within a restricted orbital space. We apply the approach to study energy profiles, interstate couplings, and the charge-transfer character of singlet and triplet exciton states of perylene di-imide aggregates (PDI). We focus on the intermolecular displacement along the longitudinal translation coordinate, which mimics different amounts of slip-stacking observed in PDI crystals. The analysis, in terms of symmetry-adapted Frenkel excitations (FE) and charge-resonance (CR) states and their interactions, discloses how the interchange of the H/J character for small longitudinal shifts, previously reported for singlet exciton states, also occurs for triplet excitons

The LAUE project for broadband gamma-ray focusing lenses

We present the LAUE project devoted to develop an advanced technology for building a high focal length Laue lens for soft gamma--ray astronomy (80-600 keV). The final goal is to develop a focusing optics that can improve the current sensitivity in the above energy band by 2 orders of magnitude.Comment: 7 pages, 6 figures, presented at the SPIE conference on "Optics for EUV, X-ray, and Gamma-ray Astronomy". To be published in the Proceedings of SPIE, vol.8147, 201

Adaptive greedy algorithms based on parameter-domain decomposition and reconstruction for the reduced basis method

The reduced basis method (RBM) empowers repeated and rapid evaluation of parametrized partial differential equations through an offline-online decomposition, a.k.a. a learning-execution process. A key feature of the method is a greedy algorithm repeatedly scanning the training set, a fine discretization of the parameter domain, to identify the next dimension of the parameter-induced solution manifold along which we expand the surrogate solution space. Although successfully applied to problems with fairly high parametric dimensions, the challenge is that this scanning cost dominates the offline cost due to it being proportional to the cardinality of the training set which is exponential with respect to the parameter dimension. In this work, we review three recent attempts in effectively delaying this curse of dimensionality, and propose two new hybrid strategies through successive refinement and multilevel maximization of the error estimate over the training set. All five offline-enhanced methods and the original greedy algorithm are tested and compared on {two types of problems: the thermal block problem and the geometrically parameterized Helmholtz problem

Process design and downstream optimization of the direct synthesis route for cleaner production of dimethyl ether from biogas

This study investigates an innovative method to produce dimethyl ether (DME) by direct synthesis from syngas derived from biogas. The proposed process was rigorously simulated in Aspen Plus, highlighting the main sections: (i) biogas tri-reforming, (ii) dimethyl-ether synthesis, and (iii) DME purification. The tri-reforming section has a CO2 and CH4 conversion of 27.3% and 96.2%, respectively A novel catalyst suitable for CO2-rich feed was chosen for the DME production to allow 60% conversion of CO2. Product separation is achieved via several absorption and distillation columns, ensuring that the operating conditions are kept mild to avoid expensive refrigeration. An optimization analysis was performed to identify the most suitable layout of the downstream process. This was identified through the evaluation of performance indicators such as utility usage and operating expenses. A wide range of purification strategies have been evaluated, and two scenarios are proposed based on the results. Configuration A produces 5.34 ktpy DME and 1.26 ktpy methanol, while Configuration B produces exclusively 6.21 ktpy DME. The process configurations were analysed by means of key techno-economic indicators and sustainability metrics. Both processes have an energy intensity of 14.5 kWh/kg. The reforming unit has a negligible footprint as it is thermally sustained from biogas combustion, but the reboilers are the main contributors for plant CO2 emissions. Configuration B has the best economic value with 11,634 k€ of NPV after 25 years and a payback time of 4 years

Risk factors for adenocarcinoma of the cervix: a case-control study.

To assess risk factors for cervical adenocarcinoma data were collected in a case-control study of 39 cases and 409 controls conducted in the greater Milan area. Questions were asked about personal characteristics and habits, gynaecologic and obstetric data, history of lifetime use of oral contraceptives and other female hormones, and general indicators of sexual habits (age at first intercourse and total number of sexual partners). The relative risk of cervical adenocarcinoma increased with number of births and abortions, early age at first birth and early age at first intercourse. These estimates did not materially change after adjustment for the potential reciprocal confounding effect. Further, there was a positive association with overweight, but an apparent association with lower education was not significant. No relationship emerged with oral contraceptive use. Thus, despite the similarities with the epidemiology of squamous cell cancer, reproductive patterns and other factors related to the risk of endometrial cancer (i.e., overweight) seem to play an important role in the risk of adenocarcinoma of cervix uteri

The Messinian paleoenvironment in the Mediterranean (Monte dei Corvi, Ancona): A comparison with the modern oceanographic conditions

The Messinian was characterized by peculiar biogeochemical dynamics and climate in the Mediterranean region, testified by widespread deoxygenation events (sapropel) and evaporite deposition. To constrain the Mediterranean response to past perturbation it is crucial to understand the current environmental crisis related to climate change. In this regard, benthic and planktic calcareous fossils provide valuable insights into surface and bottom water conditions during deoxygenation events. Here we studied in high resolution 4 sapropel-bearing cycles of the Monte dei Corvi (Ancona, Italy), which recorded the behavior of the Adriatic Deep-Water formation, a major controlling factor for the oxygenation in the modern Eastern Mediterranean. Our analysis unveils fluctuations in planktic and benthic assemblages driven by variations in insolation parameters. Sapropel interbeds deposited during insolation maxima exhibit warm-oligotrophic and Deep Chlorophyll Maximum taxa, suggesting warming and freshening of surface water, leading to weakened Adriatic Deep-Water formation and reduced oxygen delivery to the bottom. Marly limestone/marlstone interbeds exhibit the dominance of cold-eutrophic taxa and an abundance of fecal pellets with monospecific/oligospecific calcareous nannofossils taxa (Umbilicosphaera jafari and Reticulofenestra perplexa), suggesting moderately high salinity and sustained productivity during phases of strong mixing. Comparisons between Messinian and the present-day setting reveal significant differences in the abundance and distribution of calcareous planktic assemblage, mostly due to heightened productivity during the Messinian, a response to restricted conditions that increased the basin's susceptibility to nutrient-delivering runoff. This circumstance played a significant role in the widespread deoxygenation and accumulation of organic carbon during the Messinian. The uncertain trajectory of primary production in the Mediterranean complicates precise predictions of the future oxygen balance. Insights from the Messinian underscore the crucial role of primary productivity in shaping bottom oxygen conditions, emphasizing the necessity for ongoing investigation