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With substantial postglacial rhyolite eruptions and ongoing rapid uplift, the Laguna del Maule volcanic field in the southern Andes provides an exceptional opportunity to study the dynamics of an active silicic magmatic system. Using 4,093 P arrivals from 137 distant earthquakes recorded by 44 local stations over ∼2.25 years, we conduct teleseismic tomography to image the crustal structure down to 40 km below the volcanic field. A prominent low‐velocity body at depths between ∼0 and 12 km below sea level (b.s.l.), characterized by a volume of ∼500 km3 and a peak anomaly of −400 m/s (∼9%), overlaps the location of the upper‐crustal magma reservoir detected in recent gravity and surface wave tomography studies. Its estimated average P wave velocity of ∼4.6 km/s corresponds to an average melt fraction of about 14% and a melt volume of ∼70 km3. Petrologic observations are also consistent with generation and storage of rhyolitic melts at depths corresponding to the anomalous zone. Moreover, the tomographic results support a lower crust zone of MASH (melting, assimilation, storage, and homogenization) from a depth of ∼25 km to the base of the model, which likely reflects a deep crustal source of magma that contributes to and incubates the shallow silicic reservoir. Key Points: We present results of a teleseismic tomography study at Laguna del Maule volcanic field, ChileAn upper‐crustal magma reservoir of several hundred cubic kilometers is identified and characterizedFindings complement independent geophysical and petrologic observations and reveal a transcrustal magmatic system at LdMVF [ABSTRACT FROM AUTHOR]

Xylitol was produced by Scheffersomyces amazonensis UFMG‐HMD‐26.3 in hemicellulosic hydrolysate obtained from a mixture of sugarcane bagasse and straw (1:1) in batch fermentation, and was recovered using supercritical fluid. The xylitol produced was 20.11 g L−1 and the extraction approach reached a xylitol recovery of 40.51% at a high purity level of 99.59%. An analysis of energy consumption for the xylitol production process showed that xylitol production from sugarcane biomass hemicellulosic hydrolysate is feasible, highlighting the potential use of this biomass in sustainable xylitol production and supercritical fluids as a robust proposal for xylitol separation. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]

BACKGROUND A number of residues are produced during the olive oil extraction process, such as crushed pits, olive leaves, pomace and exhaust olive pomace. In addition, pruning of olive trees results in a huge amount of biomass. All of these lignocellulosic materials constitute a source of energy and chemicals that can be used as raw materials in biorefineries. Among them, antioxidants are of particular interest due to their potential applications in pharmaceutical and food industry. RESULTS: Supercritical fluid extraction (SFE) was applied on three different olive residues – pruning biomass, leaves and exhaust pomace. In this, 60% ethanol was used as cosolvent at three different pressure levels, 200, 250 and 300 bar. The best conditions for each residue were determined and compared with conventional extraction. Results show that 300 bar was the best pressure for SFE in terms of antioxidant activity of the extracts. The main polyphenolic compounds also were identified, among which hydroxytyrosol, chlorogenic acid, caffeic acid and ferulic acid were present. CONCLUSION: SFE at 300 bar proved to be the best option for obtaining a high‐activity antioxidant extract from olive leaves, exhaust pomace and pruning biomass, with hydroxytyrosol the prominent compound detected. This procedure could be integrated in a biorefinery based on olive‐derived biomass. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The Laguna del Maule (LdM) volcanic field comprises the greatest concentration of postglacial rhyolite in the Andes and includes the products of ~40 km3 of explosive and effusive eruptions. Recent observations at LdM by interferometric synthetic aperture radar and global navigation satellite system geodesy have revealed inflation at rates exceeding 20 cm/year since 2007, capturing an ongoing period of growth of a potentially large upper crustal magma reservoir. Moreover, magnetotelluric and gravity studies indicate the presence of fluids and/or partial melt in the upper crust near the center of inflation. Petrologic observations imply repeated, rapid extraction of rhyolitic melt from crystal mush stored at depths of 4–6 km during at least the past 26 ka. We utilize multiple types of surface‐wave observations to constrain the location and geometry of low‐velocity domains beneath LdM. We present a three‐dimensional shear‐wave velocity model that delineates a ~450‐km3 shallow magma reservoir ~2 to 8 km below surface with an average melt fraction of ~5%. Interpretation of the seismic tomography in light of existing gravity, magnetotelluric, and geodetic observations supports this model and reveals variations in melt content and a deeper magma system feeding the shallow reservoir in greater detail than any of the geophysical methods alone. Geophysical imaging of the LdM magma system today is consistent with the petrologic inferences of the reservoir structure and growth during the past 20–60 kyr. Taken together with the ongoing unrest, a future rhyolite eruption of at least the scale of those common during the Holocene is a reasonable possibility. Key Points: Results from a major deployment of seismic instruments at Laguna del Maule volcanic center are presentedWe use a novel application of multiple types of surface‐wave dispersion data to infer 3D shear velocity structureWe present a unified interpretation of results from seismology, geodesy, gravity, magnetotellurics, and petrochronology [ABSTRACT FROM AUTHOR]

Moving from fossil‐based economies to bio‐based economies is one of humanity's most important necessities. Bio‐based economies are sustainable alternative ways to obtain chemicals, materials, and energy, and biorefineries have been proposed as promising technological schemes for this purpose. However, the economic performance of biorefineries is strongly related to the scale of the process, as different elements (energy consumption, equipment cost, etc.) vary to different degrees when the scale varies. This situation shows the importance of evaluating the performance of the biorefinery at different scales (analysis of scale) from the design stages. The problem with the analysis of these scales is that there is no unanimous definition of 'scale' and the term is used imprecisely to refer to the raw material or product. Taking this into consideration, this work proposed a strategy for determining the Minimum Processing Scale for Economic Feasibility (MPSEF) and identifying the minimum scale at which a given biorefinery can operate. As study cases, three different biorefineries, based on different raw materials (cocoyam, Andes berry, and coffee cut stems) were used to exemplify the applicability of the design strategy. The MPSEF calculated for Andes berry, coffee cut stems, and cocoyam‐based biorefineries were 9.27, 35.6 and 683 ton day−1, respectively. These results showed the application of the design strategy and how it allows the determination of the minimum amount of feedstock to be processed to achieve a positive economic performance, and from this point, to calculate the rate of return that an investor would require and the appropriate scale to achieve it. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]

Banana-plantain fibers (BPFs) were treated with acetic anhydride (AA), epichlorohydrin (EP), and an acetic anhydride-epichlorohydrin blend (AA_EP). Natural fiber-polyester composites (PCs) were fabricated using untreated and treated BPF by the hand lay-up technique. Modified BPF Raman and Infrared spectroscopy (ATR-FTIR) analysis revealed losses of lignin and hemicelluloses and new chemical bonds that confirmed the replacement of part of the raw fiber hydroxyl groups, which gave rise to a degree of hydrophobicity in the treated fibers. This change altered their water sorption isotherms, swelling behavior in water, impedance spectroscopy, and XRD analysis. Assays of water absorption and tensile resistance for untreated BPF (U) and modified BPF polyester composites demonstrated a remarkable reduction in water intake, whereas tensile strength was maintained ( P < 0.05) for the modified BPF polyester composites. POLYM. COMPOS., 37:2960-2973, 2016. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

This research describes an enhance‐fluidity liquid extraction process for extracting total phenolic compounds (TPC) from spent blackberry pulp (SBP) using a modified solvent (CO2–ethanol mixture). Effects of particle size (from 1,400 to 180 μm), pressure (150–300 bar), and cosolvent (ethanol)‐to‐solid ratio (64, 128, and 192 mL ethanol/32 g solid) on the extraction of TPC at 40°C were investigated. Experimental data was processed using the Sovova's model to obtain the solubility of TPC in the modified solvent. The Peng–Robinson equation of state was used to correlate the solubility of phenolic compounds at high pressures. Results indicated that particle sizes ranging from 600 to 850 μm and pressure of 300 bar allowed obtaining extracts with higher antioxidant activity (94.71% of inhibition) and TPC content (11.59 mg GA/g SBP). High pressure and the modified solvent increased the solubility up to 3.4 × 10−4 (mol fraction). [ABSTRACT FROM AUTHOR]