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Carbohydrates constitute the largest source of biomass on Earth, but their synthetic modification is challenging due to their high content in oxygen functionalities. The site‐ and stereoselective modification of native sugars is a definite goal of glycochemistry research. Recent efforts to bypass the need for protecting groups, leveraging selective activation through photochemical mechanisms for site‐selective C−C bond formation from native sugars, are likely to largely impact all glycochemistry‐related areas. Davis, Koh, and co‐workers have recently presented their use of photocatalysis to develop a "cap and glycosylate" approach for the site‐ and stereoselective C‐glycosylation of native sugars. A modernized direct radical functionalization of in situ formed thioglycoside using photocatalysis was used in the synthetic manipulation of unprotected carbohydrates. This allowed reaching complex saccharides, and post‐translational modification of proteins. [ABSTRACT FROM AUTHOR]

Molybdenum catalysts bearing ONO, ON(N)O, ON(O)N and ON(S)O ligands were studied for catalytic deoxydehydration of vicinal diols. The complex bearing N′,N′‐bis(2‐hydroxy‐3,5‐dimethylbenzyl)‐N,N‐dimethylethylenediamine ligand afforded full conversion and up to 97% selectivities towards alkenes, when aliphatic vicinal diols were subjected to the reaction at 5 mol% catalyst loading. [ABSTRACT FROM AUTHOR]

This study explores the potential of using a composite material made of polylactic acid (PLA), polybutylene adipate‐co‐terephthalate (PBAT), and rice husk (RH) as an alternative for food containers. Two blends with 10 wt%–20 wt% of PBAT and four composites with 10 wt%–20 wt% of RH reinforcement are evaluated. The composite is created using an internal mixer and is analyzed using torque vs time mixing curves, melt flow index (MFI), thermogravimetric analysis, and differential scanning calorimetry (DSC). The blends exhibit higher crystallinity and superior mechanical properties compared to composites. Adding RH improves sustainability and decreases costs by utilizing agricultural waste but reduces flexural strength. However, the addition of PBAT increases flexibility, making it suitable for pliable material applications. The composite CO4 with 20 wt% of PBAT and RH demonstrates balanced performance in terms of lower MFI, thermal stability, and flexural strength, making it suitable for food tray applications. Further studies are needed to optimize the mechanical and barrier properties of these composites for specific applications. [ABSTRACT FROM AUTHOR]

2,3-Butanediol (BDO) is a crucial precursor in various industries, traditionally derived from fossil resources, raising environmental concerns. This study evaluates the techno-economic feasibility of producing BDO from wood residues, a sustainable resource abundantly available in Nordic countries. By modeling a biorefinery plant with a daily capacity of 100 metric tons of wood chips, three scenarios (Sc.) were explored: Sc. 1, where BDO is the sole product; Sc. 2, where BDO is produced alongside methane and biofertilizer; and Sc. 3, which incorporates a combined heat and power system using biogas from the waste stream. The analysis emphasizes the minimum selling price (MSP) of BDO, revealing it to be lowest in Sc. 1 at USD2.97/kg, compared to USD3.20/kg and USD3.48/kg for Sc. 2 and Sc. 3, respectively. Notably, sensitivity analysis highlighted the impact of processing capacity on economic performance, suggesting a potential for higher scalability and profitability in Sc. 2. This study contributes novel insights into the role of processing capacity and fermentation yield in optimizing BDO production, providing a valuable framework for technology developers aiming to establish wood-based biorefineries. These findings not only enhance understanding of economic thresholds but also underscore the importance of resource efficiency and strategic planning in bio-based production setups. Highlights: Economic viability of a biorefinery unit was assessed for 2,3-butanediol production. Facilities and utilities expenses were the main contributors to operating costs. Equipment and construction fees were the main contributors to total capital cost. For profitability, processing capacity should exceed 2.6-ton wood residues/h. Valorizing process waste streams increased both revenue and associated costs. [ABSTRACT FROM AUTHOR]

The current study proposes a model of an autonomous HRFS installed on different sites in 20 Saudi cities powered by renewable clean energy sources. The station is fully powered by photovoltaic (PV) panels and wind turbines involving an electrolyzer and hydrogen tank for producing and storing hydrogen. Three scenarios are investigated to propose an optimized model, namely Scenario 1 containing (PV-Wind-Battery) system, Scenario 2 with (Wind-Battery) technologies, and Scenario 3 with (PV-Battery) components. The HRFS is expected to feed the load hydrogen demand of 25 hydrogen cars with a storage tank capacity of 5 kg. The simulation is carried out using the well-known HOMER software and the description of the technical parameters of the renewable plant together with a detailed economic feasibility for the investigated cities are also performed. Furthermore, the optimization process executed demonstrates a competitive levelized cost of energy (LCOE) and levelized cost of hydrogen (LCOH) especially for the third scenario with a LCOH varying within $12–15.9/kg and LCOE in range $ 0.332–0.414/kWh, for all 20 cities. For instance, encouraging lowest values of net present cost (NPC) and LCOE are obtained for the futuristic NEOM mega city relatively to the first and third scenarios with values (NPC = $1,576,000, LCOE = $ 0.627/kWh) and (NPC = $830,494, LCOE = $ 0.332/kWh), respectively. On another hand, thorough analysis of PV/Wind hydrogen technoeconomic operation is provided including improvements recommendations, scenarios comparison and environmental impact discussion. [ABSTRACT FROM AUTHOR]

A new and practical method for the thermal degradation of technically relevant bio‐based lignin is presented. By heating a solution of lignin in highly concentrated caustic potash, vanillic acid is almost exclusively obtained in yields up to 10.6 wt %. By altering the reaction parameters, the selectivity of the reaction can be shifted towards the demethylation product, protocatechuic acid, which is obtained in a yield of 6.9 wt %. Furthermore, the procedure was applicable to different types of Kraft and organosolv lignin. To create an economically feasible process, ion exchange resins were used for the work‐up of the highly caustic reaction media without neutralizing the complete mixture. By the selective removal of the desired vanillic acid from the caustic potash, this alkaline media could directly be reused for at least 5 further lignin degradations without significant loss of yield. [ABSTRACT FROM AUTHOR]

Chemical-intensive agriculture challenges environmental sustainability and biodiversity and must be changed. Minimizing the use of agrochemicals based on renewable resources can reduce or eliminate ecosystems and biodiversity threats. Nanochitosan as a sustainable alternative offers promising solutions for sustainable agricultural practices that work at multiple spatial and temporal scales throughout the plant growth cycle. This review focuses on the potential of nanochitosan in sustainable agricultural production and provides insights into the mechanisms of action and application options of nanochitosan throughout the plant growth cycle. We emphasize the role of nanochitosan in increasing crop yields, mitigating plant diseases, and reducing agrochemical accumulation. The paper discusses the sources of nanochitosan and its plant growth promotion, antimicrobial properties, and delivery capacity. Furthermore, we outline the challenges and prospects of research trends of nanochitosan in sustainable agricultural production practices and highlight the potential of nanochitosan as a sustainable alternative to traditional agrochemicals. [ABSTRACT FROM AUTHOR]

Herein, we have reported a sustainable and chemo‐selective strategy for the synthesis of functionalized branched alcohols. A commercially available catalytic system does not need any special ligand and liberated water and hydrogen as side products. A series of alkyl primary alcohols (C4–C10), including methanol, were tolerated in good to high yield. Sequential transformations to substituted pyrroles, chromenes and synthesis of donepezil drug were obtained (>57 entries). Preliminary mechanistic investigations were performed to understand the catalytic pathways. [ABSTRACT FROM AUTHOR]

Current political and sociological efforts to respond to the need for more environmentally friendly technologies have inspired a revival of wood and wood-based material utilization in space systems. The popularity of these materials has faded since their widespread use in the early days of aerospace engineering. This work reviews the literature to provide an overview of use cases, the motivation for using wood and wood-based materials and the challenges involved. A small number of applications were identified in which wood and wood-based materials were preferred over non-renewable raw materials. They are mainly applied for less-stressed disposable components or as a thermal protection material. It can be shown that the applied wooden materials have advantages such as low production costs, easy availability, easy and environment-friendly decomposition and low weight. However, only a limited number of applications have achieved a high level of technological readiness so far. Properties such as anisotropy and a lack of uniformity, defects in wood, the quantity available material and a lack of standards for the certification of wooden materials represent challenges. These are addressed in the current research, which additionally focuses on sustainable growth, enhanced environmental friendliness and advanced lightweight design. [ABSTRACT FROM AUTHOR]

Amidst the increasing complexity of microgrid optimization, characterized by numerous decision variables and intricate non-linear relationships, there is a pressing need for highly efficient algorithms. This study introduces a tailored Mixed Integer Nonlinear Programming (MINLP) model that optimizes the charging and discharging schedules of electric vehicles (EVs) and energy storage systems (ESS) while incorporating Distributed Flexible AC Transmission System (D-FACTS) devices. To address these challenges, a novel approach based on the Large-Scale Two-Population Algorithm (LSTPA) is proposed. The model's effectiveness was evaluated using a 33-node microgrid, where the proposed method achieved a total purchased energy of 1.2 MWh, a voltage deviation of 0.0357 p.u, and a CPU time of 551 s, outperforming traditional methods like NSGA-II, PSO, and JAYA. Additionally, in a 69-node microgrid, the approach resulted in a total purchased energy of 0.3 MWh and a voltage deviation of 0.0078 p.u. These results demonstrate the superior performance of the proposed method in terms of energy efficiency, voltage stability, and computational time, advancing the efficiency of microgrid management. [ABSTRACT FROM AUTHOR]

Exploration for sustainable energy resources is essential to minimize the dependence on fossil fuels and to improve environmental parameters. Here, the possibility of utilizing bio‐waste‐derived electrolytes as an electrical energy resource by placing them across semipermeable membranes prepared through parallel stacking of coir fibers is examined. The nanofluidic membrane (d‐CF‐V) prepared by modifying the inner walls of the bio‐fluidic channels with atomically thin layers of vanadium pentoxide (VO) shows excellent perm‐selectivity (t+ = 0.87, with 1000‐fold concentration difference) and electricity conversion efficiency (≈ 28.2%). With simulated sea and river water, the d‐CF‐V yields output energy up to 2.4 W m−2, similarly with mineral acid bases (0.5 m HCl and 0.01 m NaOH), the d‐CF‐V shows an energy output of 11.8 W m−2. The sun‐dried Garcinia morella (Kuji thekera), and charred peels of Musa balbisiana (banana) are used as sustainable sources of bio‐electrolytes, which in combination with permselective d‐CF‐V yielded a power density of ≈1.4 W m−2. By replacing standard Ag/AgCl electrodes with nanomaterials exhibiting contrasting charge transfer activities, oxidized carbon nanotube membrane (o‐CNT) and polyaniline (PANI) membrane the output voltage is enhanced from –127 to –568 mV and current output is increased from 10.2 to 51.5 µA. [ABSTRACT FROM AUTHOR]

Carbon quantum dots (CQDs), as a novel category of zero-dimensional fluorescent materials, have garnered significant interest because of their distinctive optical characteristics, low toxicity, and easy surface modification. However, most techniques used to manufacture CQDs involve costly raw materials, intricate production processes, or hazardous chemicals. In this study, innovatively, low-cost, renewable, and green biomass raw material, camphor tree waste leaves, were employed to prepare CQDs through a simple one-step hydrothermal approach under relatively mild conditions. The results indicate that the prepared CQDs had a size of around 1.6 nm and a thickness of one to six layers of graphene. They can function as a reliable fluorescent probe for detecting Fe3+, exhibiting a limit of detection (LOD) of 2.03 μM. The full utilization of renewable resources, combined with relatively simple hydrothermal processing, enables the environmentally friendly and economical production of CQDs that have broad prospects for metal ion sensing applications. [ABSTRACT FROM AUTHOR]

Demand-side management of smart grid with electric vehicles (EVs) is overviewed in this review paper. The major objective of the work is to reduce the hourly peak load to obtain a steady load schedule, maximize user satisfaction and reduce cost. This review allows for the probability of leveling the everyday energy load arc and unstable demand response to hourly prices from one time period to another. To obtain a balanced everyday load schedule, increase user satisfaction, and cut costs, the main aim is to reduce peak hourly load. A management system for an EV connected to the national grid for a future household with controllable electric loads. The approach that has been presented enables the integration of EVs and renewable resources while also optimizing the demand and generation in hourly distribution. The agents are taken into account for managing load, storage, and generation; specifically, they are EV aggregators. The vehicle-to-grid (V2G) combination of electric vehicles is a key aspect of this study; with this capability, EVs may offer power grid-specific services like load shifting and congestion management. By maximizing the hourly distribution of demand as well as generation, accounting for technical limitations, and enabling the addition of EVs and RES. [ABSTRACT FROM AUTHOR]

The conventional linear system of global food production and consumption is unsustainable as it is responsible for a substantial share of greenhouse gas emissions, biodiversity declines due land use change, agricultural water stress due resource-intensive water consumption patterns and land degradation. During the last decade (1994–2014), for example, the greenhouse emissions from agriculture in Africa were reported to increase at an average annual rate of between 2.9% and 3.1%, equivalent to 0.44 Gt and 0.54 Gt CO2 per annum, respectively. Between 2000 and 2020, the greenhouse gas emissions from agrifood systems were shown to decrease in all major regions of the world, except in Africa and Asia, where they grew by 35 and 20 percent, respectively. With most of the circular agricultural practices still central to food production in the developing African countries, the continent can spearhead a global return to circular agriculture. Using a descriptive review approach, we explore the literature to examine the extent to which African agriculture is deploying these practices, the potential areas for improvement and lessons for the world in embracing sustainable food production. We underscore that the farming communities in sub-Saharan Africa have, for decades, been using some of the most effective circular agricultural principles and practices in agricultural production. We further show that practices and strategies akin to sustainable agricultural production include agronomic practices, smart irrigation options, renewable energy harvesting and waste-to-fertilizer technologies. All of these technologies, which are central to sustainable agricultural production, are not new to Africa, although they may require packaging and advocacy to reach a wider community in sub-Saharan Africa. [ABSTRACT FROM AUTHOR]

Resveratrol and 2‐thiophenemethylamine have been employed in the synthesis of a novel tri‐functional benzoxazine (RES‐th) to develop the bio‐benzoxazine monomer. The chemical structure of the synthesized monomer is confirmed by various characterization technics. The polymerization behavior is monitored by in situ Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). The in situ FTIR results reveal distinct reaction mechanisms for the three oxazine rings presented in RES‐th, with both ether and phenolic Mannich bridge structures observed in the products. The activation energy values of RES‐th are calculated to be 119.05, 120.97, and 119.44 kJ mol−1 by Kissinger, Ozawa, and Starink methods, respectively, which are all based on the heat flow curves at various heating temperatures. The thermal stability and flame retardancy of the resulting polybenzoxazine (poly(RES‐th)) are investigated by thermogravimetric analysis (TGA) and microscale combustion calorimeter (MCC). The values of Td5 and Td10 of polybenzoxazine are found to be 356 °C and 399 °C, respectively, with a char yield of 66.3% at 800 °C. The prepared polybenzoxazine also demonstrates nonflammability characteristics with the values of heat release capacity (HRC) and total heat release rate (THR) of 18.65 J (g K)−1 and 2.69 kJ g−1, respectively. These findings suggest that the thermoset, poly(RES‐th), is a promising candidate for fire‐resistant applications. [ABSTRACT FROM AUTHOR]

Microbial fuel cells (MFCs) can generate energy while processing organic pollutants, which has a great impact on environmental wastewater treatment applications. In this study, a gel polymer was formed by Co-Fe-N co-doping biochar (Co-Fe-N@BC), which was used as the anode material to improve the electricity generation performance of MFC. The Co-Fe-N@BC material prepared at 900℃ carbonised biomass into more graphitic carbon, and its total resistance (3.56 Ω) was significantly reduced. In the corresponding dual-chamber MFC, the current density was 2.81 A/m2, and the power density reached 1181 mW/m2 at maximum. Among the materials tested, the Co-Fe-N@BC anode MFC had the highest chemical oxygen demand removal rate and coulombic efficiency, reaching 91% and 13%, respectively. It is proved that MFC with Co-Fe-N@BC anode has the best electrochemical performance. [ABSTRACT FROM AUTHOR]

Higher energy consumption and poor spectrum sharing were identified as the common problems in spectrum sharing at cognitive radio networks. So to overcome these issues in the present research, a novel Horse herd-based Elman spectrum sharing model is developed. The current study found lower energy consumption and a higher spectrum sharing rate in less time. Subsequently, a channel was created for sharing the spectrum over the primary and secondary users. After that, through the proposed model, the sharing system is monitored. Moreover, the spectrum is transmitted until the false alarm is detected. The system stops the users' spectrum sharing function if a false alarm is detected. However, the spectrum is shared with every user in the designed channel. Then a case study is developed to explain the working process of the model. After that, the performance of the proposed design is detailed, and in the comparison analysis, the performance of the proposed model is compared with the existing models. Consequently, the performance of the proposed model is validated based on the throughput, outage probability, bit error rate, energy consumption, data transmission, and spectral efficiency. [ABSTRACT FROM AUTHOR]

Abstract Amidst the increasing complexity of microgrid optimization, characterized by numerous decision variables and intricate non-linear relationships, there is a pressing need for highly efficient algorithms. This study introduces a tailored Mixed Integer Nonlinear Programming (MINLP) model that optimizes the charging and discharging schedules of electric vehicles (EVs) and energy storage systems (ESS) while incorporating Distributed Flexible AC Transmission System (D-FACTS) devices. To address these challenges, a novel approach based on the Large-Scale Two-Population Algorithm (LSTPA) is proposed. The model's effectiveness was evaluated using a 33-node microgrid, where the proposed method achieved a total purchased energy of 1.2 MWh, a voltage deviation of 0.0357 p.u, and a CPU time of 551 s, outperforming traditional methods like NSGA-II, PSO, and JAYA. Additionally, in a 69-node microgrid, the approach resulted in a total purchased energy of 0.3 MWh and a voltage deviation of 0.0078 p.u. These results demonstrate the superior performance of the proposed method in terms of energy efficiency, voltage stability, and computational time, advancing the efficiency of microgrid management.

Introduction The application of various inputs, such as pesticides and chemical fertilizers, has been one of the most significant factors negatively impacting the sustainability of agricultural systems. To accurately assess the value of agricultural ecosystem services, both the positive and negative aspects of agricultural systems must be taken into account. In the past three decades, the emergy analysis has been developed for assessing environmental policies and resource quality based on the dynamics of complex environmental and economic systems. Emergy analysis can be used to evaluate the sustainability of agriculture. By definition, emergy is the amount of direct or indirect solar energy required to produce a good or service. By converting all forms of energy, resources, and services into a single unit, the solar emjoule (sej), emergy analysis can assess the interdependence of economic, social, and environmental factors. The production of three important oil crops of Sistan, including rapeseed, safflower, and sesame, was investigated using emergy and economic analysis techniques to evaluate the ecological health and productivity of the use of inputs in the production of oil crops in Sistan. Materials and Methods This research was conducted at the level of Sistan's oil plant production systems in the Northern provinces of Sistan and Baluchistan. This research used questionnaires and face-to-face interviews with the owners of small ownership systems to determine the input consumption and performance of these systems. According to their service life, the annual input energy flow in the form of structural facilities, buildings, machinery, and materials used in the systems was calculated. The RUSLE model was used to assess water erosion. Inputs are divided into four categories to analyze production systems: renewable environmental resources (R), non-renewable environmental resources (N), purchased renewable resources (FR), and purchased non-renewable resources (FN). After calculating all input and output flows, the raw data for each of the production systems was multiplied by their unit emergy value in Joules, grams, or Rials, according to Iran's conditions. This study utilized transformity, the renewable emergy ratio (R%), the rmergy yield ratio (EYR), the rmergy investment ratio (EIR), the rnvironmental loading ratio (ELR), the emergy sustainability index (ESI), the emergy exchange ratio (EER), and the emergy index of product safety (EIPS). Results and Discussion The total supporting emergy for rapeseed, safflower, and sesame production systems was calculated to be 7.28E+16, 4.75E+16, and 3.55E+16 sej.ha-1.yr-1, respectively. In all three studied production systems, wind emergy was the largest source of free environmental input. In all three studied systems, environmental non-renewable inputs accounted for the largest portion of total emergy input, which was 83.42 percent for rapeseed, 80.11 percent for safflower, and 84.4 percent for sesame. The high proportion of nonrenewable inputs in this study for all three production systems demonstrated the vulnerability of Sistan's landscape cultivation systems as a result of the obvious lack of water, severe soil erosion, and contamination of agricultural lands. The total amount of purchased inputs for rapeseed, safflower, and sesame production systems was estimated to be 1.14E+16, 8.78E+15, and 5.40E+15 sej.ha-1.yr-1, respectively. Nitrogen and phosphorus chemical fertilizers comprised the largest proportion of purchased inputs in all three systems. The transformity for rapeseed, safflower, and sesame production systems, respectively, was 3.88E+06, 3.76E+06, and 2.48E+06 sej.J-1. The higher transformability of the rapeseed production system was due to the lower input utilization efficiency of this system compared to the safflower and sesame systems. The values of the saffron system's environmental sustainability indices (ESI and ESI*), renewable energy ratio (%R), environmental loading ratios (ELR and ELR*), and modified investment ratio (EIR*) indicate that this system is more sustainable. The lower health of rapeseed and sesame systems based on emergy indices was primarily due to the large proportion of input emergy related to organic matter losses and soil erosion, which are nonrenewable environmental resources. The economic analysis revealed that the sesame production system generated a higher profit-to-cost ratio and net profit than the safflower and rapeseed systems. Conclusion This study demonstrated that emphasizing practical solutions in the comprehensive management of production ecosystems, particularly through the protection of soil organic matter and the prevention of erosion, can significantly enhance their ecological health.

In their in situ habitat, renewable resource populations are subject to stochastic growth caused by environmental variability such as fluctuations in upwelling conditions or temperature. In this paper, we examine the effects of this type of uncertainty on the noncooperative harvest decisions made by harvesters exploiting a common‐pool renewable resource. To do this, we extend the related literature on dynamic resource extraction games based on Markov strategies to allow for asymmetric extraction costs and general economic, biological, and environmental conditions. We find equilibrium behaviors that can reverse conventional wisdom. For example, in response to increasing risk caused by anticipated higher variability in biological growth, a harvester may choose to enhance conservation efforts, whereas another harvester diminishes his escapement. Increasing risk can lead to conflicts as it may increase a harvester's payoff while causing a loss to another harvester. In response to an increase in the discount rate, we find that strategic interactions can give rise to greater conservation efforts. Overall, this paper highlights the importance of adequately accounting for uncertainty and strategic behaviors in renewable resource management. [ABSTRACT FROM AUTHOR]

Perennial ryegrass (Lolium perenne) is an underutilized lignocellulosic biomass that has several benefits such as high availability, renewability, and biomass yield. The grass press-juice obtained from the mechanical pretreatment can be used for the bio-based production of chemicals. Lactic acid is a platform chemical that has attracted consideration due to its broad area of applications. For this reason, the more sustainable production of lactic acid is expected to increase. In this work, lactic acid was produced using complex medium at the bench- and reactor scale, and the results were compared to those obtained using an optimized press-juice medium. Bench-scale fermentations were carried out in a pH-control system and lactic acid production reached approximately 21.84 ± 0.95 g/L in complex medium, and 26.61 ± 1.2 g/L in press-juice medium. In the bioreactor, the production yield was 0.91 ± 0.07 g/g, corresponding to a 1.4-fold increase with respect to the complex medium with fructose. As a comparison to the traditional ensiling process, the ensiling of whole grass fractions of different varieties harvested in summer and autumn was performed. Ensiling showed variations in lactic acid yields, with a yield up to 15.2% dry mass for the late-harvested samples, surpassing typical silage yields of 6–10% dry mass. [ABSTRACT FROM AUTHOR]

Alkyl levulinates (ALs) are strategic compounds for the development of sustainable energy transition. In this regard, the direct alcoholysis of fructose and inulin for the selective ethyl levulinate (EL) production was investigated with a One‐Factor‐At‐a‐Time (OFAT) approach employing diluted H2SO4 as catalyst to clarify the role of the main reaction parameters (substrate and acid loadings, temperature, reaction time). The OFAT investigation on fructose ethanolysis allowed to reach the EL yield of 91.5 mol%. The inulin ethanolysis was then optimized adopting the multivariate approach based on the Response Surface Methodology (RSM), which highlighted the interplay of the reaction parameters on the selective EL production. This allowed to identify the optimal conditions to reach the highest EL yield (up to 89.3 mol%) and also those which ensured the highest EL concentration, adopting a substrate loading (14 wt%) higher than the majority ones reported in the literature according to the high gravity approach, and the lowest diethyl ether (DEE) by‐product yield. The DEE formation is scarcely investigated in the literature, but it can negatively influence the alcoholysis process, thus it was considered in this work. Moreover, the humin solid residue was deeply characterized to envisage its possible applications, under a circular economy perspective. [ABSTRACT FROM AUTHOR]

Biomass diesel is one of the sustainable and renewable sources of energy envisaged to hold a prominent position in the world energy infrastructure. In this study, biodiesel was produced from baobab seed oil by transesterification using biogenic heterogeneous catalyst, derived from mixed wastes of white chicken eggshells and banana fruit peels. The production process was statistically analyzed using Box-Behnken Design-Response Surface Methodology (BBD-RSM). The influential transesterification reaction parameters investigated with their ranges include reaction time (40–80 min), molar ratio of oil to methanol (1:9–1:15) and catalyst weight (3–5 wt%). The nano-catalyst (CaO-BFP-850 NPs) was prepared by calcination at high temperature of 850 °C for 4 h, and its properties were found to contain majorly the basic elements of Ca and K when investigated with analytical instruments such as SEM, EDS, DSC-TGA, FT-IR, and XRD. The regeneration test of the CaO-BFP-850 NPs conducted showed it could be reused for more than four cycles with less catalytic efficiency reduction. The ideal conditions instituted by BBD-RSM was 75 min of reaction time, 12.8:1 molar ratio of oil to methanol, and 4.08 wt% CaO-BFP-850 at 65 °C and 650 rpm constant temperature and agitation speed respectively, with the validated biodiesel yield of 96.70 wt%. The assessment of the quality of the biodiesel produced showed compliance with the standard specifications of ASTM D6751, EN 14241, and SANS 833. [ABSTRACT FROM AUTHOR]

In this study, synthesis, characterization and photopolymerization of new type of castor oil-based monomer family are studied. Electrical properties of the synthesized polymers are also evaluated. The synthesis of these materials consists of two steps. Acrylation of the castor oil and methyl ricinoleate occur in the first step and epoxidation is then followed. Epoxidized acrylated castor oil (EACO) and epoxidized acrylated methyl ricinoleate (EAMR) are synthesized at the end of the reactions. FTIR (Fourier transform infrared) and 1H NMR (nuclear magnetic resonance) spectroscopy techniques are used to characterize of the starting materials and monomers. When acrylate groups are introduced to castor oil and methyl ricinoleate, a characteristic peak at 1722 cm−1 is observed in FTIR spectrum and peaks of acrylate hydrogens at 5.7, 6.0 and 6.3 are observed in 1H NMR spectrum. After epoxidation, a small peak is detected at 840 cm−1 in FTIR spectrum and new peaks appear at 2.5 and 3.0 ppm in 1H NMR spectrum. Photopolymerization of the synthesized materials are performed with DMPA (2,2-dimethoxy-2-phenylacetophenone) and AIBN (azobisisobutyronitrile) catalyst. It is found that DMPA catalyst is more effective than AIBN. EACO samples' DC (direct current) resistance and conductance values are measured as 146.4 MΩm and 6.83 nS/m, respectively, whereas EAMR samples' DC resistance and conductance values are calculated as 96 MΩm and 10.42 nS/m, respectively. AC (alternative current) analysis is conducted by using LCR meter for the polymeric samples where EACO samples' capacitances varies from 4.88 to 3.29 pF (picofarads) with respect to frequency (10 Hz–300 kHZ). On the other hand, EAMR samples' capacitances varies from 14.7 to 6.49 pF with respect to frequency. Impedance values of the EACO samples with respect to frequency are measured as 4.24 GΩ and 165 kΩ, respectively. Impedance values of the EAMR samples with respect to frequency are measured as 1.19 GΩ and 82 kΩ, respectively. [ABSTRACT FROM AUTHOR]

The presented study provides an overview of the current research achievements and the emerging market of bio-based thermosetting polymers. Environmental attributes related to bio-based polymers trigger a steadily growing interest in this novel and promising field. Due to their importance among thermosets in terms of composite applications and quantity, this review focusses on epoxy and unsaturated polyester resins. Current studies are mainly concerned with alternative renewable raw materials to substitute fossil content and their synthesis to improve their end-properties. A common target is the increase of bio-based content within the cured resin. In spite of today's efforts in research, the recent market review reveals only few commercially available bio-based thermosetting resin systems. However, they are commonly suited for a broad variety of processing methods and applications with bio-contents up to 75%. [ABSTRACT FROM AUTHOR]

The use of plastic products or components in medical equipment and supplies results in challenges in terms of environmental sustainability and waste management for disposable, non-recyclable, and non-biodegradable materials. Medical plastic waste includes items ranging from syringes, tubing, intravenous (IV) bags, packaging, and more. Developing biodegradable replacements to petroleum-based plastics in medical equipment has not yet become an urgent priority, but it is an important endeavor. Examining alternatives involves several key themes, including material selection, testing, validation, and regulatory approval. To date, research includes studies on biodegradable polymers, composite materials, surface modifications, bacterial cellulose, three-dimensional (3D) printing with biodegradable materials, clinical trials and testing, collaboration with industry, regulatory considerations, sustainable packaging for medical devices, and life cycle analysis. The incorporation of bio-based and biodegradable plastics in the healthcare industry holds immense potential for reducing the environmental impact of medical plastic waste. The literature suggests that researchers and industry professionals are actively working towards finding sustainable alternatives that meet the stringent requirements of the medical industry. This paper reviews the efforts made so far to develop biodegradable and sustainable alternatives to plastic in medical equipment using a meta-analysis of resources, which include relevant papers published in English until June 2024. A total of 116 documents were found and screened by three reviewers for relevance. The literature reviewed indicated that various medical uses require plastics due to their unique properties, such as having strength and flexibility; being lightweight; and being able to prevent bacterial contamination. Among the alternatives, polycaprolactone (PCL), polylactic-co-glycolic acid (PLGA), starch-based acid, and polybutyric acid (PBS) have demonstrated favourable outcomes in terms of biocompatibility, safety, and efficacy. Additionally, a set of approaches to overcome these barriers and strategies is discussed alongside potential future solutions. This review aims to catalyze discussions and actions toward a more environmentally sustainable future in the medical industry by providing a comprehensive analysis of the current state, challenges, and prospects of this domain. [ABSTRACT FROM AUTHOR]

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Increasing human population demands more usage of consumable items thus causes more destruction to the environment by developing advanced materials and technologies. Synthetic plastic is one of the most used material in daily life which results in accumulation of non-degradable waste material that stays in the environment for thousands of years and creates plastic pollution. Many species on the earth suffer from pollution caused by plastic and it is one of the leading causes of global warming. For sustainable development, we need to protect our environment from plastic pollution by making use of biodegradable materials. In the past few years, biodegradable materials with plastic like properties have gained much attention. They have been made from biomass such as sugarcane, corn, wheat, rice, banana peels, etc. Such desirable properties are also present in PHAs (polyhydroxyalkanoates) synthesized by microorganisms. Several types of PHAs have been discovered from bacteria and used as a bioplastic candidate. However, there are major challenges also such as high production cost and expensive raw material which limits its commercial applications. Modern tools and strategies have allowed precise metabolic engineering of various microorganisms to produce PHAs using highly efficient microbial cell factories. This review article focuses on the research done on the microbial bioplastic production and its various applications. We have also discussed the future perspectives of bioplastic for sustainable development. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of CO2 poses a vast potential to contribute to a defossilized industry. Despite tremendous developments within the field, mass transport limitations, carbonate salt formation, and electrode degradation mechanisms still hamper the process performance. One promising approach to tweak CO2 electrolysis beyond today's limitations is pulsed electrolysis with potential cycling between an operating and a regeneration mode. Here, we rigorously model the boundary layer at a silver electrode in pulsed operation to get profound insights into the dynamic reorganization of the electrode microenvironment. In our simulation, pulsed electrolysis leads to a significant improvement of up to six times higher CO current density and 20 times higher cathodic energy efficiency when pulsing between −1.85 and −1.05 V vs SHE compared to constant potential operation. We found that elevated reactant availability in pulsed electrolysis originates from alternating replenishment of CO2 by diffusion and not from pH‐induced carbonate and bicarbonate conversion. Moreover, pulsed electrolysis substantially promotes carbonate removal from the electrode by up to 83 % compared to constant potential operation, thus reducing the risk of salt formation. Therefore, this model lays the groundwork for an accurate simulation of the dynamic boundary layer modulation, which can provide insights into manifold electrochemical conversions. [ABSTRACT FROM AUTHOR]

The growing demand for high-power DC fast-charging (DCFC) stations for electric vehicles (EVs) is expected to lead to increased peak power demand and a reduction in grid power quality. To maximize the economic benefits and station utilization under practical constraints set by regulatory authorities, utilities and DCFC station operators, this study explores and provides methods for connecting DCFC stations to the grid, employing low-power interconnection rules and distributed energy resources (DERs). The system uses automotive second-life batteries (SLBs) and photovoltaic (PV) systems as energy buffer and local energy resources to support EV charging and improve the station techno-economic feasibility through load shifting and charge sustaining. The optimal sizing of the DERs and the selection of the grid interconnection topology is achieved by means of a design space exploration (DSE) and exhaustive search approach to maximize the economic benefits of the charging station and to mitigate high-power demand to the grid. Without losing generality, this study considers a 150 kW DCFC station with a range of DER sizes, grid interconnection specifications and related electricity tariffs of American Electric Power (AEP) Ohio and the Public Utility Commission of Ohio (PUCO). Various realistic scenarios and strategies are defined to account for the interconnection requirements of the grid to the DCFC with DERs. The system's techno-economic performance over a ten-year period for different scenarios is analyzed and compared using a multitude of metrics. The results of the analysis show that the the integration of DERs in DCFC stations has a positive impact on the economic value of the investment when compared to traditional installations. [ABSTRACT FROM AUTHOR]

The transition to a hydrogen-based economy presents a promising solution to the challenges posed by unsustainable energy systems and reliance on fossil fuels. This comprehensive review explores various hydrogen production methods, emphasizing their technological advancements, sustainability implications, and future prospects. Beginning with an overview of hydrogen's significance as a clean energy carrier, the review examines key production methods such as Steam Methane Reforming, Electrolysis (Proton Exchange Membrane, alkaline, solid oxide), Biomass Gasification, Photoelectrochemical Water Splitting, and Thermochemical Processes. Each method is scrutinized for its efficiency, environmental impact, and scalability, providing valuable insights into their roles in advancing the hydrogen economy. The review highlights the transformative potential of hydrogen production to replace fossil fuels due to its ability to store renewable energy long-term and its zero emissions. It also discusses potential technological advancements, including high-efficiency solid-state electrolysis and advanced catalysts for water splitting, highlighting avenues for innovation in hydrogen production. Additionally, policy recommendations aimed at promoting the hydrogen economy and fostering collaboration between academia, industry, and governments are elucidated. Through a detailed analysis of hydrogen production technologies and future prospects, this review contributes to shaping the trajectory of sustainable energy systems, advancing the adoption of hydrogen as a key energy vector, and underscoring the importance of alternative and sustainable energy sources. • Hydrogen economy addresses unsustainable energy challenges. • Review covers key hydrogen production methods and technologies. • Examines efficiency, environmental impact, scalability of each method. • Highlights advances in catalysts and solid-state electrolysis. • Recommends policies for renewable integration, innovation, and collaboration. [ABSTRACT FROM AUTHOR]

The article examines the role of green hydrogen in reducing CO2 emissions in the transition to climate neutrality, highlighting both its benefits and challenges. It starts by discussing the production of green hydrogen from renewable sources and provides a brief analysis of primary resource structures for energy production in European countries, including Romania. Despite progress, there remains a significant reliance on fossil fuels in some countries. Economic technologies for green hydrogen production are explored, with a note that its production alone does not solve all issues due to complex and costly compression and storage operations. The concept of impure green hydrogen, derived from biomass gasification, pyrolysis, fermentation, and wastewater purification, is also discussed. Economic efficiency and future trends in green hydrogen production are outlined. The article concludes with an analysis of hydrogen-methane mixture combustion technologies, offering a conceptual framework for economically utilizing green hydrogen in the transition to a green hydrogen economy. [ABSTRACT FROM AUTHOR]

For an extended period, international economists have focused on trade policies related to natural resources in developing countries. However, prevailing analytical frameworks primarily examine the impact of export and import policies when natural resource stocks are subject to singular or distinct adverse externalities. In contrast, developing nations with less stringent environmental management regulations frequently grapple with open-access and industrial pollution externalities. This research extends the analysis of trade policies on natural resources by incorporating the concurrent presence of within- and inter-industry externalities, thereby significantly altering the autarkic equilibrium’s character. A two-sector general equilibrium model assesses the economic, stock conservation, and welfare implications of implementing export and import taxes on renewable resource commodities. The study reveals that resource-exporting countries’ enforcement of resource export taxes can yield a triple win, contingent on the relative damage inflicted by open-access renewable resources and manufacturing sectors. Conversely, import taxes imposed by resource-importing nations result in a triple loss. Furthermore, the model suggests that import subsidies for resource goods can promote resource conservation and welfare benefits compared to free trade without trade policies, mainly when pollution dominates open-access externality in terms of depleting on the environmental stock. [ABSTRACT FROM AUTHOR]

Oleate hydratases open a biocatalytic access to hydroxy fatty acids by hydration of unsaturated fatty acids. Their practical applicability, however, is hampered by their low stability. In this study we report the immobilization of the oleate hydratase from Rhodococcus erythropolis PR4 on functionalized porous, spherical polymer beads. Different carrier materials promoting covalent, hydrophobic, ionic and his‐tag affinity were screened and immobilization yields typically >95 % were observed. The highest activity recovery of 32 % was achieved by immobilization via ionic interaction with quaternary ammonium functionalized beads. Biochemical properties of the enzyme immobilized via ionic interaction remain unchanged upon immobilization. The immobilized enzyme was applied for synthesis of 10‐hydroxystearic acid remaining stable under process conditions. Conversion of up to 100 mM oleic acid gave 10‐hydroxystearic acid achieving a TON of up to 19,000. Successful recycling of the biocatalyst for up to ten cycles further demonstrate its potential for the synthesis of 10‐hydroxystearic acid. [ABSTRACT FROM AUTHOR]

Although biomass‐based alternatives for the manufacturing of bioplastic films are an important aspect of a more sustainable future, their physicochemical properties need to be able to compete with the existing market to establish them as a viable alternative. One important factor that is often neglected is the long‐term stability of renewables‐based functional materials, as they should neither degrade after a day or week, nor last forever. One material showing high potential in this regard, also due to its intrinsic biodegradability and antibacterial properties, is chitosan, which can form stable, self‐standing films. We previously showed that green additives introduce a broad tunability of the chitosan‐based material properties. In this work, we investigate the long‐term stability and related degradation processes of chitosan‐based bioplastics by assessing their physicochemical properties over 400 days. It was found that the film properties change similarly for samples stored in the fridge (4 °C, dark) as at ambient conditions (20 °C, light/dark cycles of the day). Additives with high vapor pressure, such as glycerol, evaporate and degrade, causing both brittleness and discoloration. In contrast, films with the addition of crosslinking additives, such as citric acid, show high stability also over a long time, bearing great preconditions for practical applications. This knowledge serves as a stepping‐stone to utilizing chitosan as an alternative material for renewable‐resourced bioplastic products. [ABSTRACT FROM AUTHOR]

Due to climate change, the transition from petroleum-based materials to renewable sources is essential. Lignin, a complex aromatic polymer derived from lignocellulosic biomass, offers a promising alternative. This study is focused on optimizing lignin recovery from black liquor based on the LignoBoost™ process and evaluating its application in acrylonitrile butadiene rubber (NBR). The optimized conditions (80 °C, pH 2.0) yielded lignin with significantly lower phenolic hydroxyl group concentrations compared to lignins prepared according to the design of the experiment (DoE). Surface property analysis revealed a high surface free energy of 55.3 mJ/m², indicating potential for interaction with various substances. A DoE approach to investigate the influence of precipitation conditions on lignin properties is employed in the study. NIR spectroscopy and surface property measurements were used for lignin characterization. The results demonstrated that hydroxyl group concentrations, influenced by black liquor freshness and filtration temperature is significantly affected by the preparation method. Notably, pilot lignin (PL) application in NBR composites resulted in a more than twofold increase in tensile strength and elongation at break compared to NBR without additives or with commercial lignin. These findings suggest that lignin recovered through optimized processes can enhance the mechanical properties of NBR, offering a sustainable alternative to traditional additives. This research provides valuable insights for further exploration of lignin’s potential in industrial applications, particularly in the context of lignin recovery and utilization in pulp mills. [ABSTRACT FROM AUTHOR]

Energy storage systems have an important effect on increasing the flexibility of power grids and are necessary to achieve the goals of smart grids. So far, many researches have been conducted in the field of optimal utilization of batteries, but most of them have studied the effects of batteries only on the side of the transmission or distribution network. In the present study, the effect of the installation and optimal operation of energy storage systems on both sides of the transmission and distribution network has been investigated. This paper presents a bi-level optimization model for integrated energy management in transmission and distribution smart grids along with demand management issues. Considering that both proposed models are mixed integer linear programming models, it is difficult to solve them by direct methods. Therefore, a method based on the change of variables and KKT equations is presented to solve these problems, and globally optimal solutions to these problems are guaranteed. Several integrated systems that include transmission and distribution networks are considered to evaluate the proposed model and method, and the results show that the proposed model is efficient and shows the positive effect of modeling energy storage systems on both sides of the network. [ABSTRACT FROM AUTHOR]

There is good evidence that fatty acid derivatives have antibacterial activity and represent a promising approach to developing the next generation of antibacterial agents. In the present work, some new isoquinolin derivatives were synthesized via the Betti reaction. Three-component reaction of aryl aldehydes, 2,7-naphthalenediol and ammonium carboxylate of fatty acids with different chains in EtOH under reflux conditions offered related isoquinolin compounds in good to excellent yields. Some advantages of this procedure are short reaction times, free catalyst, high yield of products and easy work-up. The structure of synthesized compounds was characterized by IR, 1H, and 13C NMR data as well as microanalysis results. In addition, these novel materials were evaluated for their biological activities against Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922) bacteria. The obtained data confirm that isoquinolin derivatives 4c, 4e, 4f, 4g, 4m, 4n, 4p, 4q exert excellent antimicrobial activity against these tested bacterial strains. [ABSTRACT FROM AUTHOR]

In response to the environmental impacts of conventional polyurethane adhesives derived from fossil fuels, this study introduces a sustainable alternative utilizing lignin-based polyols extracted from rice straw through a process developed at INESCOP. This research explores the partial substitution of traditional polyols with lignin-based equivalents in the synthesis of reactive hot melt polyurethane adhesives (HMPUR) for the footwear industry. The performance of these eco-friendly adhesives was rigorously assessed through Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), rheological analysis, and T-peel tests to ensure their compliance with relevant industry standards. Preliminary results demonstrate that lignin-based polyols can effectively replace a significant portion of fossil-derived polyols, maintaining essential adhesive properties and marking a significant step towards more sustainable adhesive solutions. This study not only highlights the potential of lignin in the realm of sustainable adhesive production but also emphasises the valorisation of agricultural by-products, thus aligning with the principles of green chemistry and sustainability objectives in the polymer industry. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the properties of biodegradable plantable pots made from biomaterials. Specifically, rapeseed straw and cow manure biomaterials were studied here because these biomaterials add nutrients to the soil during their biodegradation and are readily available agricultural by-products. Furthermore, the use of biomaterials helps in replacing the plastic materials which are currently used to make pots and decreases the environmental impact by producing a cleaner product. The physical and mechanical properties of biocomposites pots were investigated and optimized in the present work. The effect of mixing ratio (straw: cow manure) in the composite, straw particle size, and chemical pre-treatments of straw by 1% HCl or 2% NaOH on the physical and mechanical properties of biodegradable pots was investigated. Additionally, the Taguchi method and ANOVA statistical analyses were employed for parameters optimization. The results indicated the straw to cow manure ratio exhibited a significant effect on the compression strength (CS), penetration strength (PS), and water absorption (WA) of pots. While the CS and PS of pots decreased with increasing the ratio of straw from 2 to 10% and increasing the particle size of straw from 1.5 to 3.0 mm, these changes increased the water absorption of pots (126.52–141.21% for 1.5-mm untreated straw). Chemical pre-treatments of straw investigated here resulted in decreased CS and PS of pots. The straw ratio in the straw/manure mixture is the most significant factor affecting the characteristics of biodegradable pots. [ABSTRACT FROM AUTHOR]

Copyright of Bitácora Urbano/Territorial is the property of Bitacora Urbano/Territorial and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With a continually evolving society and increasing environmental energy concerns, green biomass materials are attracting considerable attention in the field of energy storage owing to their low cost, environmental friendliness, and excellent storage capacity. Biomass materials prepared by various methods have been used as electrodes in secondary batteries. In this review, we discuss the application scope of different types of biomass and biomass‐derived materials in zinc‐air, lithium‐ion, and lithium‐sulfur batteries. The application of biomass and biomass‐derived materials in batteries is gaining increasing attention and is expected to drive many exciting innovations in the field of sustainable energy storage technologies. [ABSTRACT FROM AUTHOR]

In the ever-evolving landscape of power networks, the integration of diverse sources, including electric vehicles (EVs) and renewable energies like wind power, has gained prominence. With the rapid proliferation of plug-in electric vehicles (PEVs), their optimal utilization hinges on reconciling conflicting and adaptable targets, including facilitating vehicle-to-grid (V2 G) connectivity or harmonizing with the broader energy ecosystem. Simultaneously, the inexorable integration of wind resources into power networks underscores the critical need for multi-purpose planning to optimize production and reduce costs. This study tackles this multifaceted challenge, incorporating the presence of EVs and a probabilistic wind resource model. Addressing the complexity of the issue, we devise a multi-purpose method grounded in collective competition, effectively reducing computational complexity and creatively enhancing the model's performance with a Pareto front optimality point. To discern the ideal response, fuzzy theory is employed. The suggested pattern is rigorously tested on two well-established IEEE power networks (30- and 118-bus) in diverse scenarios featuring windmills and PEV producers, with outcomes showcasing the remarkable excellence of our multi-purpose framework in addressing this intricate issue while accommodating uncertainty.

Fuel cell is one of the promising technologies in the production of clean energy that does not have the pollution of fossil fuels. In this technology, the chemical energy resulting from the reaction is directly converted into electrical energy. This system does not follow the Carnot cycle, so it does not have the limitations of internal combustion engines and has multiple efficiency compared to them. This system consists of two electrodes and an electrolyte in between and has different types according to the type of electrolyte. One of the factors that reduce the optimal performance of fuel cells is polarization, which is divided into three categories: ohmic, kinetic, and activation. Today, one of the newest energy production and conversion systems is the fuel cell technology, which is compatible with the environment and renewable resources. It has attracted the attention of scientists. Fuel cells are devices that convert the chemical energy of fuel directly into electrical energy. A fuel cell is like a battery, but it can provide electrical energy for a longer period of time than a battery. This paper Review, a comprehensive overview of fuel cell science and engineering with emphasis on hydrogen fuel cells. The document provides a concise, up-to-date overview of fuel cell fundamentals, their history, competing technologies, types, advantages and challenges, applications and markets for portable, stationery and transportation, current status of research and development, future goals, design levels, thermodynamic and electrochemical principles, system evaluation factors, prospects and outlook. The latest data from industry and academia was used, and the connection between fuel cell fundamentals and applications was emphasized throughout the manuscript.