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Lignin, an abundant natural resource, has not been effectively utilized. In this study, the functionality of lignin was enhanced through amination to produce amine-crosslinked lignin, and its adsorption behavior toward cationic and anionic dyes was investigated. Chemical structure analysis confirmed the successful introduction of amine groups, thereby improving the molecular weight and thermal stability of the optimized amine-crosslinked lignin. Additionally, the amine-crosslinked lignin exhibited a larger specific surface area than kraft lignin, as well as excellent adsorption capacity for both anionic and cationic dyes. Furthermore, it selectively adsorbed anionic and cationic dyes depending on pH conditions. The adsorption kinetics were described using a pseudo-second-order model, and the adsorption isotherms for congo red and methyl green were determined using the Langmuir and Freundlich equations, respectively. Additionally, the reusability and adsorption efficiency of the optimized amine-crosslinked lignin were evaluated, confirming its stable and repeatable adsorption efficiency for congo red and methyl green even after five repeated cycles. The assumed adsorption mechanism was attributed to electrostatic interactions. Therefore, the successful synthesis and excellent adsorption properties of amine-crosslinked lignin suggest its promising potential for environmentally friendly and efficient removal of both cationic and anionic dyes, thereby offering a sustainable solution for wastewater treatment and remediation., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Bioethanol is recognized today as the most coveted biofuel, not only because of its tendency to reduce greenhouse gas emissions and other undesirable impacts associated with climate change, but also because of the simplicity of its methodology. This study evaluated bioethanol production from cocoa waste hydrolysates at the laboratory scale and, then evaluating the environmental impact associated with this production. Acid treatment was carried out on the hydrolysate in order to make it more accessible to ethanol-producing microorganisms. The cocoa hydrolysate was converted on a laboratory scale into bioethanol. The Ca, Mg, K and Na content of the substrate were respectively 78.4 ± 0.04; 109.59 ± 0.03; 1541.53 ± 0.08 and 195.05 ± 0.12 mg/L. The iron and total phosphorus contents were found to be at 14.06 ± 0.07 and 97.54 ± 0.01 mg/L respectively. The hydrolysate's biochemical oxygen demand (BOD 5) was 1080 ± 0.01 mg/L. A two per cent alcohol yield was obtained from 50 mL of substrate. Environmental impacts were assessed and quantified using SimaPro software version 9.1.1.1, Ecoinvent v.3.6 database, ReCiPe Midpoint v.1.04 method and openLCA sustainable development software. A total of 15 impact factors were assessed and quantified. The categories with more significant impacts in the agricultural phase were land use (1.70 E+04 m 2 a crop eq), global warming (3.41 E+03 kg CO 2 eq) and terrestrial ecotoxicity (7.23 E+03 kg 1,4-DCB), which were the major hotspots observed in the lab-scale biomass-to-bioethanol conversion phase due, to the use of electricity, distilled water and chemicals. The result of this work has shown that the cocoa-based hydrolysate is a suitable substrate for the sustainable production of liquid biofuels., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Wind energy technology, particularly power generation by wind turbines, has received substantial attention due to resource depletion and global warming concerns. These concerns highlight the importance of conducting studies to enhance their efficiency by increasing their power output. The goal of this work was to combine the RSM (Response Surface Methodology (RSM) with CFD (Computational Fluid Dynamics) to discover the optimal design parameters and conditions for ducted wind turbines. To that purpose, twenty-seven runs were chosen using Central Composite Design (CCD) in the design phase. Duct simulation was performed by employing different dimensional parameters and feeding them into a third-order polynomial that fitted to an eight-order function. The analyzed runs discussed the maximum available wind velocity and power at the throat area of the various designed ducts. The wind-enhanced power and speed were studied under different design parameters, and their effects were discussed. The optimum design conditions to capture maximum power were 0.16 m, 2, and 1.5 for design parameters of the duct's throat diameter, contraction ratio, and length-to-throat diameter ratio, respectively. A good selection of design parameters can increase the outpour power up to six times as a general result. By modeling CFD simulations using the RSM method, it is possible to minimize the time and cost of calculation to find the optimized range for the design parameters of the ducts., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

Fluorescence is well-known nowadays as one of the most efficient anti-counterfeiting techniques. Zinc oxide quantum dots (ZnOQds) are exceptionally fluorescence when exposed to ultraviolet (UV) light, which makes them a candidate for anti-counterfeiting printing. The resulting anti-counterfeiting papers are sustainable and resistance against organic dyes. In this work, ZnOQds were prepared via a green method and characterized under UV-visible spectroscopy, along with microscopic observations by transmission electron microscopy (TEM) and crystallography by X-ray diffraction (XRD). Formation of ZnOQds nanocrystals with an average partials size of 7.3 nm was approved. Additionally, double-layers sheets were prepared at two loading concentrations of ZnOQds, namely 0.5 and 1 (wt./v) and underwent characterization using a topographical surface study via field emission scanning electron microscopy (FE-SEM). Hybrid sheets were mechanically more stable compared to single-layer paper and likewise polymer film. Moreover, aging simulation approved a high stability for hybrid sheets. Particularly, the photoluminescence emission affirmed anti-aging character of hybrid paper for more than 25 years. The hybrid sheets also showed a broad range of antimicrobial activity., Competing Interests: The authors declare no conflict of interest., (©2023PublishedbyElsevierLtd.)

Spar caps, which cover 50% of the cost of windmill blades, were made of unidirectional and biaxial glass/carbon reinforcements of 600 gsm with thicknesses ranging from 100 to 150 mm for blades 70-80 m long. The significance of this study was to utilize an economical biodegradable material i.e bamboo fabric of 125 gsm to fabricate a lightweight composite and study its behavior for spar caps applications. The aim of this research was to investigate the effect of weave pattern and composite size at coupon level under thermal, dynamic, water absorption, and flammability conditions. Composites comprising 125 gsm plain and twill weave bamboo as reinforcements/AI 1041 Phenalkamine bio-based hardener with epoxy B-11 as matrix were tested. Thermo-Gravimetric Analysis revealed that the weave pattern and composite thickness had an effect on the rate of weight loss and sustenance until 450 °C. The pattern had an effect on the glass transition temperature, as seen by Differential Scanning Calorimetry. The weave pattern and size thickness had an effect on energy storage and dissipation, displaying the damping behavior in DMA. The weave pattern and size had an effect on the rate of water absorption, which saturated after a few hours. The wettability and thickness of composites hampered the burning rate, with 5.4 mm thickness resulting in a 30% decrease., Competing Interests: The authors declare no competing interests., (© 2023 Published by Elsevier Ltd.)

The demand of natural cellulosic fibers has been increasing day by day due to their versatile uses and eco-friendly nature. The reason behind this demand is due to some unique properties of natural fibers that are suitable for several fibrous applications such as in composite, textile, nano-materials, conductive carbon, biomaterials etc. In this study, a new natural cellulosic fiber is extracted from the bark of the jack tree branches by water retting process. The fiber is characterized by standard methods. The result of the chemical compositions of the fiber shows that it contains α-cellulose 79.32%, hemicellulose 8.01%, lignin 6.77%, ash 3.58% and extractives 2.32%. XRD analysis reveals its high level of crystallinity (86%) and the microfibrillar angle (MFA) calculated from the XRD data is found -29°. The FTIR analysis confirms the presence of expected functional groups. Thermogravimetric analysis (TGA) and the derivative thermogravimetric (DTG) reveal its good thermal stability and the maximum degradation occurred at 358 °C for the degradation of the α-cellulose. The density of the fiber is found 1.05 g/cc, which is lower compared to many other known natural fibers. All these properties of this new fiber are suitable for several sophisticated fibrous applications such as reinforcement in composite, textile, cellulose nano-materials, activated or conductive carbon, biomaterials etc., Competing Interests: The authors declare no conflict of interest., (© 2022 The Author(s).)