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[Display omitted] • Lignin valorization process superstructure optimized by mathematical modelling. • Performances of different biorefineries were assessed based on the type of technical lignin. • Phenol-formaldehyde resins revealed the highest costs and yields. • Vanillin production was a profitable option to valorize lignin. • Aromatic monomers can be an opportunity when their market price exceed 2.00€/kg. Lignin, the most abundant aromatic biopolymer on Earth, is often considered a biorefinery by-product, despite its potential to be valorized into high-added-value chemicals and fuels. In this work, an integrated superstructure-based optimization model was set up and optimized using mixed-integer non-linear programming for the conversion of technical lignin to three main biobased products: aromatic monomers, phenol–formaldehyde resins, and aromatic aldehydes/acids. Several alternative conversion pathways were simultaneously compared to assess the profitability of lignins-based processes by predicting the performance of technologies with different TRL. Upon employing key technologies such as hydrothermal liquefaction, dissolution in solvent, or high-temperature electrolysis, the technical lignins could have a market value of 200 €/t when the market price for aromatic monomers, resins, and vanillin is at least 2.0, 0.8, and 15.0 €/kg, respectively. When lower product selling prices were considered, the aromatic monomers and the resins were not profitable as target products. [ABSTRACT FROM AUTHOR]

In this study, an algae biomass gasification process using a dual fluidized bed with combined power and methanol cogeneration was developed. The gasification process was modeled using Aspen Plus and validated using experimental data of two microalgae species (Nannochloropsis oculata and Dunaliella salina) commonly found on the western coast of Saudi Arabia. The impacts of different operating conditions, including the gasifier temperature, steam-to-biomass ratio, and algae-char split ratio, on the compositions of four main gases (CO, CO2, CH4, and H2) were investigated. The results of the parametric studies indicated that the gasification temperature has a significant effect on the composition of the synthesis gas, where 700–850 °C was the ideal operating range for gasification. Altering the ratio of biomass to steam showed a slightly smaller effect on the synthesis gas composition. The char split ratio should be kept below 75% to ensure an adequate heat supply to the process. The proposed process successfully converted 45.7% of the biomass feed to methanol at a production capacity of 290 metric tons per day. On the other hand, 38 MW of electricity capacity was generated in the combined power cycle. [ABSTRACT FROM AUTHOR]

[Display omitted] • Optimized phenolic resin shows high CO 2 uptake of 3.06 mmol/g at 273 K and 1 bar. • High CO 2 /N 2 selectivity and surface area achieved using optimized polymer OPTP-8. • Synthesis parameters optimized via response surface design for maximum performance. • Techno-economic analysis indicates potential for low-cost production of OPTP-8. Amidst rising global concerns about climate change, the capture and sequestration of carbon dioxide (CO 2) from industrial emissions is becoming increasingly critical. In the present study, a phenolic resin-based porous polymer for CO 2 capture is developed, offering a solution to the dual challenges of efficacy and cost in current carbon capture technologies. Optimization of synthesis parameters, including temperature, reaction time, and catalyst amount was performed using response surface methodology (RSM) to maximize surface area and economic benefits. The optimized polymer demonstrated a substantial CO 2 adsorption capacity of 3.06 mmol/g at 273 K and 1 bar, with a specific surface area of 860 m2/g. An early-stage techno-economic analysis of sorbent synthesis was conducted, relating cost to sorbent quality and surface area. It was found that producing the polymer at low temperatures is more cost-effective, while synthesis at higher temperatures offers operational advantages. This research addresses a gap in existing literature by focusing on the sorbent material and its economic viability, paving the way toward the commercialization of such adsorption technology. [ABSTRACT FROM AUTHOR]

Various kinetic models of methanol dehydration to dimethyl ether over a commercial γ‐alumina catalyst were compared with a view to selecting the most appropriate model as a basis for process optimization. To achieve significant improvements in the conventional design, the Berčič‐and‐Levec kinetic model was employed and process intensification was applied to develop a more energy‐efficient process, by enhancing the adiabatic reactor performance and maximizing the heat recovery from the highly exothermic reactor. The single‐pass conversion of methanol was increased to 83 %, with an inlet temperature of 217 °C to the adiabatic reactor. Application of process intensification resulted in an improved flowsheet, which reduced the total energy requirements by 59.3 % and cut the CO2 emissions by 60.8 %. [ABSTRACT FROM AUTHOR]

With the effort to use alternative refrigerants with lower global warming potential (GWP), the majority of these alternative refrigerants are classified as slightly flammable. In this paper we report on the numerical evaluation of a catastrophic leak scenario of R-32 refrigerant from a 3-ton roof top air conditioning unit (RTU) which serves a 12.2 × 9.14 × 2.4 m room. A full rupture of a 6.35 mm (¼ inch) pipe downstream of the evaporator coil is simulated. Two separate cases with refrigerant releases of 1.81 kg and 3.62 kg charge have been studied. The two charges are released in 10.2 and 20.4 s, respectively, just after the end of a unit cooling cycle. The flammable volume inside the room existed only for about 40 s with a maximum flammable volume inside the room of 1.12% of the total room volume for the 3.62 kg charge case. [ABSTRACT FROM AUTHOR]

A preliminary analysis was conducted to analyze the performance of a heat pump water heater (HPWH) that uses CO 2 as the refrigerant. A model to predict the performance was developed and calibrated based on the experimental data for an existing HPWH using a CO 2 refrigerant. The calibrated model was then used to run a parametric analysis in which factors such as water supply temperature, water circulation rate, tank stratification, and condenser configuration were considered. The performance of a commercial CO 2 system was compared with that of a similar system using R-134a as the refrigerant. It was found that CO 2 HPWH performance was comparable to that of an R-134a HPWH, more so for a separated gas cooler configuration. For comparable performance, the compressor size and the tube-in-tube heat exchanger (condenser/gas cooler) size were compared for CO 2 - and R-134a-based systems. The impact of the water circulation rate on the water temperature stratification in the tank, an essential requirement for higher performance for CO 2 HPWH systems was also investigated. [ABSTRACT FROM AUTHOR]

Owing to the growing concerns about the relatively high global warming potential (GWP) of current refrigerants, a serious effort is in progress to find lower-GWP substitutes. The hydrofluoroolefin (HFO)-based refrigerants R1234yf and R1234ze(E) are being considered for use in multiple heating, ventilation, air conditioning, and refrigeration applications because of their very low GWP. A study was conducted to model a residential heat pump water heater using these HFOs. A system model was calibrated using experimental data and the calibrated model was used to evaluate the potential of HFOs to replace R134a. A series of parametric analyses were used to investigate the impacts of condenser wrap pattern, condenser tube size, evaporator size, and heat loss factor from the storage tank. It has been shown that both R1234yf and R1234ze(E) can be substituted for R134a with comparable performance and no substantial modifications to the original system. This study presents a detailed feasibility analysis for successful replacement of high-GWP refrigerants with low-GWP refrigerants with acceptable performance. [ABSTRACT FROM AUTHOR]

Water heating, dehumidification and space cooling are responsible for significant energy consumption in buildings. A potential energy saving measure is to develop hybrid systems that can utilize the sensible and latent heats removed in space cooling to heat water. In this paper, we present experimental results on a hybrid system that utilizes the latent heat released in the dehumidification process for water heating. This system absorbs water vapor from the air and transfers the heat of phase change into the process water. The absorbed water vapor is then liberated in a desorber and subsequently condensed in a condenser, while its latent heat is transferred to the process water. The condensed water vapor can then be either drained (if dehumidification is desired), or utilized in an evaporative cooling process (if sensible space cooling is desired). In essence, the system can exchange both sensible and latent heats with its ambient. The main innovations implemented in the system are (1) a semi-open absorption system architecture to lower the system cost, (2) a membrane-based absorber to alleviate the liquid entrainment issue encountered in the conventional packed bed absorbers and (3) an ionic liquid that eliminates the crystallization risks and minimizes corrosion issues normally associated with LiBr-based absorption systems. A water heating thermal COP of 1.4 is achieved at 30°C, 70% RH ambient conditions. [ABSTRACT FROM AUTHOR]

• Lignin solubilisation mechanism in pure solvents and mixtures elucidated. • Novel cost-effective and sustainable process developed for fractionating lignin. • Challenges of design and scale-up for integration into value chains identified. • Techno-economic and environment, health and safety metrics developed for benchmarking. The aim of this work is to develop a novel green solvent based sustainable process to refine lignin into low molecular weight (LMW) and high molecular weight (HMW) fractions. Lignin dispersity reduction were experimentally determined using four solvent mixtures, and benchmarked against eight pure solvents. Data outputs were used for modelling the integrated fractionation process. Dispersity reduction of up to 73% was achieved for the high value LMW fraction. Also, a 90% reduction of energy requirement was achieved with an optimized process incorporating a mechanical vapor compression system. This study showed that solvent mixtures involving water can significantly reduce the cost, environment, health and safety impacts of lignin fractionation. Techno-economic evaluation confirmed the economic viability of a large-scale process processing 50 tonne/day of lignin. [ABSTRACT FROM AUTHOR]

Psychiatric care often presents ethical challenges, particularly when patients with severe mental illness refuse essential treatment. This case report examines the ethical complexities surrounding covert prescribing in a noncompliant psychiatric patient. A 54-year-old male with schizophrenia, admitted following an auto-pedestrian accident resulting in multiple fractures, illustrates these dilemmas. His refusal of medication despite experiencing severe psychosis led healthcare providers to administer antipsychotics covertly, with the consent of his medical power of attorney. The report explores the ethical implications of such practices, especially concerning patient autonomy and safety. It underscores the urgent need for interdisciplinary collaboration and the establishment of standardized guidelines to ethically navigate covert prescribing in psychiatric patients., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Razzak et al.)

The development of recyclable crosslinked thermosetting fibres is a challenging research topic. In the present work, we have designed and synthesized polyurethane fibres from fructose-derived 5-chloromethylfurfural (CMF) and lignin-derived monomeric phenols. The greenhouse gas emissions associated with the production of CMF showed comparable results to that of 5-hydroxymethylfurfural (HMF), a high potential sugar-based platform molecule. The wet-spun biobased polyurethane fibres produced could be conveniently crosslinked using Diels-Alder chemistry to effectively enhance the glass transition temperature and mechanical properties. At a mildly elevated temperature (140 °C), the chemically crosslinked fibres could be effectively de-crosslinked, which enabled complete separation from a mixture with poly(ethylene terephthalate) (PET) and cotton fibres. These results outline a potential strategy to design and fabricate new biobased fibres with reversible crosslinking, which may enable fibre-to-fibre recycling., (© 2024 Wiley‐VCH GmbH.)

A crucial aspect of adding an economical and environmental dimension to the upgrading of bio-oils is to develop catalysts with enhanced and prolonged activity. In the present study, the effect of doping δ-alumina (Al 2 O 3 ) with oxides of cerium (Ce) and lanthanum (La) before thermal treatment was investigated. The performance of such an Al 2 O 3 -supported nickel-molybdenum (Ni-Mo) catalyst was evaluated by studying the selectivity for the direct hydrodeoxygenation (HDO) of vanillin to cresol under continuous-flow conditions. In addition, the effect of adding H 2 S during catalyst activation and/or performance tests was also evaluated. Overall, enhanced performance of the doped NiMo catalyst in the HDO process has been demonstrated and an increased selectivity for cresol via direct HDO observed. The advantage of adding La and Ce is supported by the characterization results, where less sintering and enhanced pore diameter of the doped Al 2 O 3 were observed after thermally inducing the transformation from the δ to θ phases. The improved characteristics and prolonged activity of the doped Al 2 O 3 were also deduced by the lower acidity of the catalyst, which resulted in reduced coke formation during the HDO process., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Lignin is an abundant polyaromatic polymer with a wide range of potential future uses. However, the conversion of lignin into valuable products comes at a cost, and medium- to high-value applications are thus appropriate. Two examples of these are polymers (e.g., as fibers, plasticizers, or additives) and flow batteries (e.g., as redox species). Both of these areas would benefit from lignin-derived molecules with potentially low molecular weight and high (electro)chemical functionality. A promising route to obtain these molecules is oxidative lignin depolymerization, as it enables the formation of targeted compounds with multiple functionalities. An application with high potential in the production of plastics is the synthesis of new sustainable polymers. Employing organic molecules, such as quinones and heterocycles, would constitute an important step toward the sustainability of aqueous flow batteries, and lignin and its derivatives are emerging as redox species, mainly due to their low cost and renewability., Competing Interests: O.Y.A. and A.K. are inventors on a European patent application (EP22710346.2) and, together with C.P.H., have co-founded a spin-off company (GreenRFB AB) that aims to produce lignin-based batteries using methods described in this perspective article., (© 2024 The Author(s).)

Few-shot learning aims to identify unseen classes with limited labelled data. Recent few-shot learning techniques have shown success in generalizing to unseen classes; however, the performance of these techniques has also been shown to degrade when tested on an out-of-domain setting. Previous work, additionally, has also demonstrated increasing reliance on supervised finetuning in an off-line or online capacity. This paper proposes a novel, fully self-supervised few-shot learning technique (FSS) that utilizes a vision transformer and masked autoencoder. The proposed technique can generalize to out-of-domain classes by finetuning the model in a fully self-supervised method for each episode. We evaluate the proposed technique using three datasets (all out-of-domain). As such, our results show that FSS has an accuracy gain of 1.05%, 0.12%, and 1.28% on the ISIC, EuroSat, and BCCD datasets, respectively, without the use of supervised training.

The efficient valorization of lignin is crucial if we are to replace current petroleum-based feedstock and establish more sustainable and competitive lignocellulosic biorefineries. Pulp and paper mills and second-generation biorefineries produce large quantities of low-value technical lignin as a by-product, which is often combusted on-site for energy recovery. This Review focuses on the conversion of technical lignins by oxidative depolymerization employing heterogeneous catalysts. It scrutinizes the current literature describing the use of various heterogeneous catalysts in the oxidative depolymerization of lignin and includes a comparison of the methods, catalyst loadings, reaction media, and types of catalyst applied, as well as the reaction products and yields. Furthermore, current techniques for the determination of product yields and product recovery are discussed. Finally, challenges and suggestions for future approaches are outlined., (© 2022 The Authors. ChemSusChem published by Wiley-VCH GmbH.)

Biodiesel considered a green, environmentally friendly, and renewable energy source is one of the most promising candidates to replace fossil fuels to supply energy for the world. The conventional thermocatalytic methods have been extensively explored for producing biodiesel, while inevitably encountering some drawbacks, such as harsh operating conditions and high energy consumption. The catalytic production of biodiesel under mild conditions is a research hotspot but with difficulty. Photocatalysis has recently been highlighted as an eco-friendly and energy-saving approach for biodiesel production. This mini-review summarizes typical photocatalysts for biodiesel production and discusses in detail the catalytic mechanism and strategies of the photo-driven (trans)esterification to produce biodiesel. The current challenges and future opportunities of photo-driven catalysis to prepare biodiesel are also outlined, in steps towards guiding the design of advanced photocatalysts for biodiesel production., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Huang, Jian, Zhu, Abdelaziz and Li.)

The planning target volume (PTV) depends on the method of radiotherapy guidance. This study aimed to measure the systemic and random errors using an online marker matching and offline bone structure matching to estimate PTV marker , PTV bone , or PTV laser for treatment verification and radiotherapy guidance, especially in centers lacking radiotherapy fiducial markers (FMs). Thirty patients with localized prostate cancer who were treated with FM-based dose escalation protocol were included. The initial set-up was done with laser marks and daily megavoltage images were acquired. The systematic and random errors were calculated. PTV marker , defined as the sum of maximum marker migration, and PTV calculated to compensate for the difference between online marker matching and offline analysis of marker matching. PTV marker was added to estimated PTV from online marker matching to obtain PTV laser . PTV skin marks migration , was calculated and deducted from PTV laser to acquire PTV bone . The mean maximum marker migration was 2 ± 1.2 mm. The resultant values of PTV marker were 2.7 ± 0.6 mm, 3.3 ± 1.1 mm, and 4.4 ± 2.2 mm, in the lateral (lat.), longitudinal (long) & vertical (vert.) directions, respectively, whereas values of PTV laser were 13 ± 0.6 mm, 17.7 ± 1.1 mm, and 15.8 ± 2.2 mm, and PTV bone were 5.9 ± 0.6 mm, 8.6 ± 1.1 mm, 7.2 ± 2.2 mm, respectively, in the lat., long., and vert. directions. Our results show that PTV needed with FM-based image guidance ranged between 3 and 4 mm in the three cardinal directions, was 10 mm smaller than that required with laser skin marks guidance, and narrower by 5 mm compared to that obtained by offline bone structure image matching.

Purpose: To evaluate the effectiveness and safety of image-guided percutaneous sclerotherapy using bleomycin for macrocystic and bevacizumab (Avastin™) for microcystic orbital lymphatic malformations in children., Materials and Methods: Between October 2015 and July 2018, we prospectively evaluated 10 pediatric patients who presented clinically and radiologically with lymphatic malformations and were treated with percutaneous sclerotherapy. Patients with venous malformations were excluded. Eight females and two males with ages ranging from 3 to 17 years (mean: 8.8, SD: 4.9) were included. Guided with ultrasound and fluoroscopy, macrocysts were treated with bleomycin instillation. For microcystic components in three patients, bevacizumab was injected intralesional. All patients underwent ultrasound and non-contrast MRI to evaluate response to treatment after 6 weeks., Results: The malformations were macrocystic in seven patients and complex (macro/microcystic) in three. Twenty sclerotherapy sessions were performed, (range: 1-3 sessions, mean: 2, SD: 0.8). Clinically, there was a significant reduction in the proptosis after treatment (P = 0.007) and dystopia (P = 0.018). The local radiological response showed a reduction in the maximum lesions diameters and volumes after treatment (P = 0.005 and 0.005, respectively). Two of the three patients treated with bevacizumab showed a reduction in the lesions volumes by 90.4% and 63.4%, respectively, whereas one patient did not show volume reduction. Transient periorbital edema and ecchymosis occurred following the procedure with no major complications encountered. Follow-up ranged from 9-33 months, mean: 20.3, SD: 7.4., Conclusion: Bleomycin sclerotherapy is a safe and effective treatment for orbital macrocystic lymphatic malformations. Further use of bevacizumab for microcystic lesions in a larger series is required to outline its efficacy and safety.

Lignin is a major component of lignocellulosic biomass and as such, it is processed in enormous amounts in the pulp and paper industry worldwide. In such industry it mainly serves the purpose of a fuel to provide process steam and electricity, and to a minor extent to provide low grade heat for external purposes. Also from other biorefinery concepts, including 2nd generation ethanol, increasing amounts of lignin will be generated. Other uses for lignin - apart from fuel production - are of increasing interest not least in these new biorefinery concepts. These new uses can broadly be divided into application of the polymer as such, native or modified, or the use of lignin as a feedstock for the production of chemicals. The present review focuses on the latter and in particular the advances in the biological routes for chemicals production from lignin. Such a biological route will likely involve an initial depolymerization, which is followed by biological conversion of the obtained smaller lignin fragments. The conversion can be either a short catalytic conversion into desired chemicals, or a longer metabolic conversion. In this review, we give a brief summary of sources of lignin, methods of depolymerization, biological pathways for conversion of the lignin monomers and the analytical tools necessary for characterizing and evaluating key lignin attributes., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)

Aim: To evaluate the effect of portal vein thrombosis and arterioportal shunts on local tumor response in advanced cases of unresectable hepatocellular carcinoma treated by transarterial chemoembolization., Methods: A retrospective study included 39 patients (mean age: 66.4 years, range: 45-79 years, SD: 7) with unresectable hepatocellular carcinoma (HCC) who were treated with repetitive transarterial chemoembolization (TACE) in the period between March 2006 and October 2009. The effect of portal vein thrombosis (PVT) (in 19 out of 39 patients), the presence of arterioportal shunt (APS) (in 7 out of 39), the underlying liver pathology, Child-Pugh score, initial tumor volume, number of tumors and tumor margin definition on imaging were correlated with the local tumor response after TACE. The initial and end therapy local tumor responses were evaluated according to the response evaluation criteria in solid tumors (RECIST) and magnetic resonance imaging volumetric measurements., Results: The treatment protocols were well tolerated by all patients with no major complications. Local tumor response for all patients according to RECIST criteria were partial response in one patient (2.6%), stable disease in 34 patients (87.1%), and progressive disease in 4 patients (10.2%). The MR volumetric measurements showed that the PVT, APS, underlying liver pathology and tumor margin definition were statistically significant prognostic factors for the local tumor response (P = 0.018, P = 0.008, P = 0.034 and P = 0.001, respectively). The overall 6-, 12- and 18-mo survival rates from the initial TACE were 79.5%, 37.5% and 21%, respectively., Conclusion: TACE may be exploited safely for palliative tumor control in patients with advanced unresectable HCC; however, tumor response is significantly affected by the presence or absence of PVT and APS.