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Bulky cellulosic network structures (BRC) with densities between 60 and 130 g/l were investigated as a sustainable alternative to fossil-based foams for impact liners in bicycle helmets. The mechanical properties of BRC foams were characterized across a wide range of strain rates and incorporated into a validated finite element model of a hardshell helmet. Virtual impact tests simulating both consumer information and certification scenarios were conducted to compare BRC-lined helmets against conventional expanded polystyrene (EPS) designs. Results showed that BRC outperformed EPS in oblique impacts, reducing angular accelerations and velocity changes by approximately 33 %, particularly for z-axis rotations. The average risk of sustaining AIS2 injuries and concussions was lower for BRC (8 % and 34 % respectively) compared to EPS (13 % and 46 %). However, BRC helmets exhibited bottoming out in certain straight impacts, potentially failing certification tests. This limitation was addressed through design modifications. The study demonstrates that cellulosic fibre network structures have the potential to replace fossil-based foams in bicycle helmets while providing adequate protection and improved performance in mitigating rotational forces., 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 Published by Elsevier Ltd.)

Greener and sustainable synthetic strategies have been evolving as the demanding domain of organic synthesis during the last decade. Green synthesis involves the development of method that decrease or eliminate the use of hazardous chemicals, and make use of renewable or recyclable resources. By incorporating the fundamentals and methodologies of green synthesis, organic chemists have the ability to develop valuable organic molecular frameworks which also demonstrate a strong commitment to environmental sustainability. In this context, the nanoparticle has garnered significant interest due to its various features, adhering to the principles of green synthesis. Specifically, magnetic nanoparticles have been trending extensive uses in green synthesis throughout the past decade. The role of magnetic nanoparticle has an irreplaceable place in the synthesis of biologically valuable frameworks named as quinoline. Quinoline are considered a privileged structure among organic compounds and offer a promising avenue for identifying lead structures in the search of new synthetic molecules (Saquinavir, Imiquimod and Reabamipide) having potential medicinal values and other important prospects. So, it's always indeed to the organic and medicinal chemist to develop biologically active frameworks by the green synthesis. The current manuscript consolidates the existing research on properties of environment-friendly magnetic nanoparticles for generating an extended range of valuable quinoline derivatives., 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. Published by Elsevier Ltd.)

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).)

Almaciga ( Agathis philippinensis Warb.), a tropical conifer that is tapped for its resin commercially known as Manila copal, grows in many parts of the Philippines, but resin buyers prefer and pay a better price for resin from southern Palawan. The study was done to characterize almaciga resins obtained from commercial sites in Davao Oriental and Palawan (Brooke's Point and Marufinas) to explain the quality and price differences. Fresh and aged resin samples were subjected to wet chemical, thermal, and spectral analyses. Generally, the resin samples were found to be soluble in the more polar solvents although significant variations were observed for resins from various sites. Titrimetric determination revealed no significant variation in acid and saponification values, although the Brooke's Point resin had significantly lower unsaponifiable components. Predominant Fourier transform infrared spectroscopy (FTIR) absorption peaks for fresh resin include strong C=O stretch and weak = C-H stretch. Aged Palawan resins, which showed increased solubility in polar solvents, exhibited increased intensity of prominent FTIR peaks such as O-H stretch and C=O stretch. The weak peak at 1719 cm -1 seen in fresh Palawan resins was no longer observed in aged resins. DSC revealed the semi-crystalline nature of almaciga resin and melting temperatures similar to diterpenoid resin acids. This is attributed to the presence of increasing amounts of oxidized abietic acids as shown by gas chromatography-mass spectrometry (GCMS). For the Davao Oriental resins, significant amount of agatholic acid was shown, while resin acids of the abietane and pimarane type were conspicuously absent in the GC-MS spectrograms. The study found evidence that almaciga resins from Davao and Palawan differ in chemical composition and physical properties, which could explain the quality and price differences., Competing Interests: The authors declare no conflict of interest., (© 2021 Published by Elsevier Ltd.)

Boswellia papyrifera woodland provides considerable economic, ecological and socio-cultural benefits in the drylands of Ethiopia. However, its populations are in rapid decline due to human pressure and environmental degradation. As a consequence, the species is now considered being endangered, demanding an urgent conservation intervention to sustain its existence. This study was carried out in the Abergele district, northern Ethiopia, with objectives to characterize the current population structure of B. papyrifera and prioritize its potential conservation intervention alternatives using Analytical Hierarchy Process (AHP) modelling techniques. The woody species related data were collected from 33 sample plots randomly established in the study area. Data related to the potential intervention alternatives and their evaluating criteria were collected from experts, personal experiences and intensive literature reviews, and then validated using stakeholders' focus group discussion. Four candidate alternatives were then considered for the AHP: 1) free grazing with no tapping resting period (FGNTR), 2) free grazing with a rotational tapping (FGRT), 3) area exclosure with medium tapping resting period (AEMTR), and 4) area exclosure with long tapping resting period (AELTR). The results showed that the population structure of B. papyrifera is unstable and is characterized by low density (266 trees ha -1 ), absence of regeneration and saplings (DBH<10 cm) due to different interrelated disturbances such as overgrazing, over tapping, pests, agricultural expansion and poor managements. The overall priority ranking value of all stakeholders using the AHP techniques also indicated that AEMTR (with overall rank value of 0.352) and AELTR (0.294) as the best alternatives strategies, respectively, for sustainable B. papyrifera woodland conservation. For the success of these strategies, their economic impacts at their early implementation stages (5-10 years) should be minimized by collecting different non-timber forest products from the woodland. Continuous capacity building training on sustainable utilizations and managements of B. papyrifera woodland should also be provided for all relevant stakeholders., (© 2020 Published by Elsevier Ltd.)

Highly porous nanofibrillated cellulose aerogel fibers (NFCA) prepared from bagasse pulp was used as a template for in situ preparation of alumina nanorods. NFCA was soaked in aluminum nitrate aqueous solution followed by soaking in ammonium hydroxide solution to generate aluminum hydroxide within the porous structure and at surface of NFCA. Sintering of NFCA/Al (OH) 3 was carried out at 1100 °C to produce nano-sized alumina with rod-like structure. The synthesized Al 2 O 3 nanorods were investigated using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and high resolution transmitted electron microscope (HR-TEM). The Al 2 O 3 rods had width from 123 to 86 nm while their length was in the micrometer range, as shown from SEM and HR-TEM images. The selected area X-ray diffraction (SEAD) showed rhombohedral crystal structure. XRD pattern confirmed formation of α-alumina. Energy dispersive X-ray spectroscopy (EDX) showed purity of the prepared Al 2 O 3 .

Lignocellulosic fibers, which obtained from Citrus trees trimmings, were modified with Aspergillus flavus (EGYPTA5) enzymes. The non-modified and the modified lignocellulosic fibers were used with low density polyethylene (LDPE) by melt blending brabender method at 170 °C with different ratio (5, 10 and 20 wt%) to obtain wood plastic composites (WPC). The prepared samples were characterized using Fourier-transformed infrared (FT-IR), Scan Electron Microscope (SEM), and Water vapor transmission rate (WVTR) as well as, the mechanical, thermal, biodegradability and swelling properties were examined. The fabricated WPC displayed good mechanical and thermal properties compare with pure LDPE. Also, the WVTR was enhanced by the addition of modified lignocellulosic fibers over the unmodified one. Moreover, the enzymes assay such as cellulase and lignin peroxidase enzymes were estimated and confirming the growing of fungi on the lignocellulosic fiber in solid state fermentation condition to improve lignin peroxidase production and eliminate cellulose enzymes. The fabricated WPC can be used in different environmental application such as packaging system, that it will be green, economic, and partially biodegradable.

Optimizing the desired properties for stretch monolayer separators used in Lithium-ion batteries has been a challenge. In the present study a cellulose nanofiber/PET nonwoven composite separator is successfully fabricated, using a wet-laid nonwoven (papermaking) process, which can attain optimal properties in wettability, mechanical strength, thermal resistance, and electrochemical performance simultaneously. The PET nonwoven material, which is fabricated from ultrafine PET fibers by a wet-laid process, is a mechanical support layer. The porous structure of the composite separator was created by cellulose nanofibers coating the PET in a papermaking process. Cellulose nanofibers (CNFs), which are an eco-friendly sustainable resource, have been drawing considerable attention due to their astounding properties, such as: incredible specific surface area, thermal and chemical stability, high mechanical strength and hydrophilicity. The results show that the CNF separator exhibits higher porosity (70%) than a PP (polypropylene) separator (40%). The CNF separator can also be wetted by electrolyte in a few seconds while a PP separator cannot be entirely wetted after 1 min. The CNF separator has an electrolyte uptake of 250%, while a PP separator has only 65%. Another notable finding is that the CNF separator has almost no shrinkage when exposed to 180 °C for 1 h, whereas a PP separator shrinks by more than 50%. Differential Scanning Calorimetry (DSC) shows that the CNF separator has a higher melting point than a PP separator. These findings all indicate that the CNF 29 separator will be more favorable than stretch film for use in Lithium-ion batteries.