Secondary Fiber Research Articles

Utilization of Alternative Fibres Manufactured from Recycled PET Bottles in Concrete Technology for the Improvement of Fire Resistance

This article addresses the potential use of secondary polymer fibres in the field of structural concrete as a replacement for primary polymer fibres (mainly polypropylene/PP/), which are used in concrete to enhance its resistance when exposed to high temperatures (especially in the case of fire). Research has shown that, in addition to PP fibres, polyethylene terephthalate/PET/fibres, produced by recycling packaging materials (mainly PET bottles), can also be used as an alternative. These fibres are industrially produced in similar dimensions as PP fibres and exhibit similar behaviour when added to fresh and hardened concrete. In terms of their effect on increasing resistance to extreme heat loads, it has been found that despite a higher melting point (Tm), concrete with these fibres demonstrates comparable fire resistance. Therefore, it can be concluded that secondary PET fibres represent an interesting alternative to primary PP fibres from the perspective of a circular economy, and their use in construction represents a potentially valuable application for PET obtained through the collection and recycling of PET packaging materials.

Histochemical and gene expression changes in Cannabis sativa hypocotyls exposed to increasing concentrations of cadmium and zinc

Hemp (Cannabis sativa L.) is a versatile crop that produces cellulosic bast fibres used in textiles and biocomposites. Is also finds use in phytoremediation, being a good candidate for the cultivation on marginal lands, such as those contaminated by heavy metals (HMs). HMs like cadmium (Cd) and zinc (Zn) are known to affect plant growth and impair the biosynthesis of cellulose and lignin at the cell wall level. Since cellulose is the major component in the gelatinous layer of bast fibres, HMs can impact the structure of hemp fibres and, consequently, their mechanical properties. This study investigates how varying concentrations of Cd and Zn in the soil affect the bast fibres of hemp plantlets. The chosen model is the hypocotyl, as it is ideal for studying bast fibre development: it exhibits a temporal separation between the elongation and thickening phases within a short period of approximately three weeks. C. sativa plantlets were grown for 20 days, and the hypocotyls sampled to perform histochemical observations, gene expression analysis, as well as to quantify biomass yield and Cd/Zn accumulation. Hemp plantlets grown in soils with the three highest Zn concentrations were smaller than the control group, whereas no decrease in size was observed under elevated Cd concentrations. However, at the highest Cd concentration, the root system exhibited enhanced development, accompanied by a significant increase in dry weight across all the concentrations tested. The quantification of Cd and Zn showed that the roots were the main organs accumulating HMs. Cd at the two highest concentrations decreased significantly the lumen area of bast fibres and increased their cell wall thickness. Zn decreased significantly the lumen area, but it did not impact the thickness of the cell wall at the highest concentration. Cd also increased the number of secondary fibres. Immunohistochemistry highlighted a different pattern of crystalline cellulose distribution with a signal that was less homogeneous in the presence of Cd and Zn. Gene expression analysis revealed changes in transcripts encoding cellulose synthases, fasciclin-like arabinogalactan proteins, class III peroxidases. The results obtained shed light on the molecular response and bast fibre histological changes occurring in young hemp plants exposed to Cd and Zn.

MicroRNA expression profiles reveal wool development and fineness regulation in Gansu alpine fine-wool sheep

The development of wool has a complex regulatory mechanism both influenced by genetic and environmental factors. MicroRNAs (miRNA) were involved in various biological processes of animals, and may play an important role in the regulation of wool development. In this study, we comprehensively analyzed and identified the histological parameters of hair follicles, as well as the miRNAs, target genes, pathways, and Gene Ontology terms related to wool fineness regulation and wool growth and development using HE staining and RNA-Seqs methods. Both coarse (group C, mean fiber diameter (MFD) = 22.26 ± 0.69 μm, n = 6) and fine (group F, MFD = 16.91 ± 0.29 μm, n = 6) of Gansu alpine fine-wool sheep with different wool fineness were used in this study. The results showed that the primary follicle diameter and secondary wool fiber diameter in group C were significantly higher than those in group F (P < 0.05). And the number of primary and secondary hair follicles in group C was significantly lower than that in group F (P < 0.05). Furthermore, a total of 67 DE miRNAs and 290 potential DE miRNAs target genes were screened in the skin tissues of sheep from groups F and C, and some potential target genes related to wool fineness regulation were screened, such as CDH2, KRT82, FOXN1, LOC101106296, KRT20, MCOLN3, KRT71, and TERT. These genes were closely related to Glutathione metabolism, epidermal cell differentiation, keratinization, and regulation of hair cycle. Moreover, the regulatory network of miRNAs-mRNAs suggested that miRNAs (miR-129-x, novel m0079-3p, miR-2484-z, novel m0025-5P, etc.) may play a key role in the wool development and wool fineness regulation of Gansu alpine fine-wool sheep. In summary, this study expands the existing miRNAs database and provides new information for studying the regulation of wool development in Gansu alpine fine wool sheep.

Treatment of secondary fiber papermaking wastewater with aerobic granular sludge cultured in a sequencing batch biofilter granular reactor

Abstract Secondary fiber papermaking wastewater (SPW) has received increasing interest because of its enormous discharge, typical high COD, and low biodegradability. The dense and compact structure of aerobic granular sludge (AGS) results in a high sludge concentration in the sequencing batch biofilter granular reactor (SBBGR), which provides superior conditions for the treatment of highly concentrated wastewater. This study constructed an SBBGR to treat SPW, investigated the changes in the species and structural characteristics of pollutants during wastewater treatment, and analyzed the dominant populations that can degrade pollutants in the SPW. The results showed that SBBGR had a good treatment effect on SPW and the removal rates of COD, TN, TP, SS, and color were 90.3 %, 81.9 %, 85.2 %, 73.1 %, and 75.1 % respectively with the influent organic load of 8.1 kg COD m−3 d−1, which was attributed to its outstanding biodegradability. The types and quantities of aromatic compounds in SPW were significantly reduced, according to the results of FTIR, UV–vis, and GC-MS. Microbial community analysis showed that the presence of Bacteroidetes, Proteobacteria, Macellibacteroides, Chlorobium, and Brachymonas in the SBBGR was responsible for the outstanding biodegradation of pollutants in the SPW. In summary, the treatment of SPW with SBBGR is extremely promising for applications.

Characteristics and degradability of laser print waste paper fiber reinforced PLA resin matrix composite materials

AbstractAs is well known, Laser print paper is usually produced with high‐quality chemical wood pulp. The laser print waste paper fiber (LPWF) is a high‐quality secondary fiber, and the research and development of high‐value utilization technology for laser print waste paper has attracted much attention in the field of renewable resource recycling. In this study, LPWF was used to reinforce poly(lactic acid) (PLA) composites in the field, and the composites were modified with bioenzyme, cationic polyacrylamide (CPAM), and nano‐silicon carbide (Nano‐SiC) to enhance the interfacial compatibility of LPWF/PLA composites. The study systematically investigated the effects of various modification methods on the characteristics and degradability of composites made from laser print waste paper fiber reinforced PLA resin matrix. The results showed that the mechanical properties of the composites treated with CPAM and Nano‐SiC were significantly improved, with tensile strengths of 54.3 and 59.5 MPa, and flexural strengths of 85.1 and 91.5 MPa, respectively, and the water absorption of the composites was reduced after the modification treatment, while the thermal stability was improved. The degradation performance of the composites in various water environments indicated that the inclusion of LPWF accelerated the water degradation rate of the composites, with the maximum degradation rate of the composite reaching 1.26% in 30 days.Highlights Laser print waste paper is an excellent quality recyclable fiber resource. Four modifiers were used to modify LPWF/PLA composites. Characteristics and degradability of the composites were investigated. Significantly improved properties of CPAM and Nano‐SiC modified composites. The degradation rate of composites is increased by the addition of LPWF.

Effect of gestational naural pasture allowance on muscle development of lambs

To study the effects of gestational undernutrition induced by a lower natural pasture allowance on myogenesis and meat production in lambs, two experiments were carried out. In the first, Corriedale sheep were fed contrasting natural pasture allowances (23 days before conception until gestation day 122) and myogenesis was evaluated in 70-day-old fetuses and newborns. In the second, similar ewes were fed with contrasting natural pasture allowances (day 30 of gestation until parturition) and the productive performance, quantity and quality of meat and muscular characteristics in 200-day-old lambs were evaluated. A lower pasture allownace affected fetal myogenesis (fewer secondary fibers) and was associated with reduced mitotic and myoblastic fusion activity in some muscles. In newborns, maternal undernutrition affected muscle histology, fibrillar biological and contractile properties (MyHC-I and GLUT-4). Likewise, undernutrition strongly reduced muscle IGF-1 and could compromise neonatal hypertrophic compensation. On the other hand, maternal undernutrition from day 30 to parturition affected growth, carcass quality and muscle weights at 200 days, although these effects were mainly sex-dependent, with males being the most affected. Maternal undernutrition affected fibrillar composition (greater oxidative activity) in all muscles at 200 days. Biochemical and meat quality characteristics were also affected, although these effects depended on both muscle and sex. In summary, a lower gestational pasture allowance negatively affected fetal myogenesis and neonatal muscle characteristics (worse hypertrophic capacities), and induced fetal programming effects on muscle mass and muscle characteristics at 200 days. This implies that, regardless of postnatal conditions, intrauterine alterations induce muscular changes, which may be related to the ability to grow and the quality of the meat produced. Likewise, our results highlight the importance of considering the sex of the animal and the muscle when studying these effects.

Reinforcements of cationic polyvinyl alcohol with low dosage for secondary fibre

ABSTRACT The effect of polyvinyl alcohol, a green water-soluble polymer, usually is not satisfied as a secondary-fiber reinforcing agent in pulp and paper-making industry due to the same negative charges of PVA and pulp fiber. In this study, 3-chloro-2-hydroxypropyltrimethylammonium chloride was used as an etherifying agent to prepare cationic modification of polyvinyl alcohol (CPVA) with degree of etherification of 0.059 under a reaction time of 4 hours and n(PVA : etherifying agent) = 1 : 0.5. Compared with PVA, CPVA exhibits positive charge and smaller particle size, enabling it to effectively combine with negatively charged fibers and get in between the fibers. As a result, CPVA demonstrates a remarkable ability to improve the paper’s physical properties. With a dosage of only 0.2% CPVA (based on the absolute dry pulp), which is merely 1/10 of the dosage of PVA, CPVA increases the paper’s tensile index by 54.09%, burst index by 25.96%, and tear index by 21.09%. CPVA as a reinforcing agent for secondary fiber pulps, which can be attributed to the alteration in charge, to enhance CPVA’s affinity for the electrostatic interaction of the fibers. Consequently, CPVA emerges as a viable and eco-friendly enhancement solution, demonstrating significant potential in secondary fiber reuse.

Lifecycle Assessment of Strategies for Decarbonising Wind Blade Recycling toward Net Zero 2050

The wind energy sector faces a persistent challenge in developing sustainable solutions for decommissioned Wind Turbine Blades (WTB). This study utilises Lifecycle Assessment (LCA) to evaluate the gate-to-gate carbon footprint of high-profile disposal and recycling methods, aiming to determine optimal strategies for WTB waste treatment in the UK. While this article analyses the UK as a case study, the findings are applicable to, and intended to inform, recycling strategies for WTB waste globally. Long-term sustainability depends heavily on factors like evolving energy grids and changing WTB waste compositions and these must be considered for robust analysis and development strategy recommendations. In the short to medium term, mechanical recycling of mixed WTB waste is sufficient to minimise Global Warming Potential (GWP) due to the scarcity of carbon fibre in WTB waste streams. Beyond 2040, carbon fibre recycling becomes crucial to reduce GWP. The study emphasises the importance of matching WTB sub-structure material compositions with preferred waste treatment options for the lowest overall impact. Future development should focus on the extraction of carbon fibre reinforced polymer (CFRP) structures in WTB waste streams, commercialising large-scale CFRP structure recycling technologies, establishing supply chains, and validating market routes for secondary carbon fibre products. In parallel, scaling up low-impact options, like mechanical recycling, is vital to minimise WTB waste landfilling. Developing viable applications and cost-effective market routes for mechanical recyclates is necessary to displace virgin glass fibres, while optimising upstream recycling processes based on product requirements.

Enhancing the mechanical strength of corrugated medium paper through instant catapult steam explosion pretreatment of tobacco stem

The decline in mechanical properties of secondary fiber upon multiple recycling iterations necessitates the incorporation of cost-effective and environmentally friendly fibers to counterbalance strength loss. In this study, an orthogonal experiment design was employed to optimize the SE process to acquire tabocco stem pulp (TSP). The study systematically investigated the influence of steam pressure, residence time, and alkali dosage employed during impregnation were investigated. Notably, the research identified alkali dosage as the most significant parameter impacting system performance. Under optimized conditions (1.2 MPa, 5 min, and 5 %), the prepared paper using 100 % TSP exhibited the capability to attain Grade C corrugated medium. TSP, subsequently, served as a compensatory material for mitigating the loss of strength observed in low-quality secondary fibers (LSF). Remarkably, the introduction of 20 wt% TSP resulted in the production of grade B products, showcasing exceptional enhancement in ring-crush strength. The breaking length of paper was increased with an additional 0.5 wt% PAE added, resulting in all criteria achieving the highest grade A. In conclusion, the study elucidated the synergistic and complementary effects of TSP and LSF, wherein stiff TSP fiber bundles formed a network that effectively supported LSF filling. This study identified the relationship between SE parameters and fiber properties, conclusively establishing waste tobacco stem as a quality fiber source conducive to producing high-quality paper.

Stimuli factor of muscular receptors, extraocular muscles and oculocardiac reflex (OCR)

Introduction: The oculocardiac reflex (OCR) was first described in 1908 as a reduction in heart rate secondary to direct pressure on the eyeball. OCR has been described during ophthalmologic procedures. This is also a standard test for peripherical autonomic and vagal system with the diving reflex and overtraining. The aim studied the specificities of stimuli of stretch receptors wich can be the traction at the extraocular muscles. Materials: 7 rabbits were included on the study. The anesthesia was done by an Intraperitoneal administration of ethyl carbamate. During all the study the rabbit is immobilized with a gripping frame for the head. Heart rate and RR were measured with EKG was recorded online. Methods: Bilateral pressure is applied using a mechanical pressure compression device, ranging from 100 to 800 mmHg, either instantaneously or in 15 or 30 seconds. For each pression we studied the variations of the RRspace (RRmax and RRt function of time) compared with the RRcontrol. If no variation, RRmax/RRcontrol and RRt/RRcontrol =1 Results: Response to abrupt compression RRmax varied linearly and significantly with pression. Response to progressive compression did not show any significant variation either during rise of pressure or when pressure was reached. Time-based response was studied from 56RR intervals. With abrut compression, the increase was effective from the first or second RR intervals. Depending on the pressure, it increased up to the 20th, presented a peak and decreased even with maintained pressure. The RR interval reverted to the control (RR/tRR = 1) around the 40th interval. With progressive stimulation, the maximum elongation value is lower, with an identical decay. Discussion: Our work showed the characteristics of stimulating factor: we used pressure on eyeballs, as in a sports medicine test (cardiac parasympathetic analysis) and in emergencies for the reduction of arrhythmias. This principal factor is tension in function of time, with an elongation of the periorbital muscles and the neuromuscular spindle. This is a proprioceptive sensory mecano-receptor sensitive to elongation. It is made up of primary neuromuscular fibers known as nuclear sac fibers and secondary neuromuscular fibers known as nuclear chain fibers. The former are 'phasic' (i.e. reacting to a variation in tension) and the latter 'tonic' (i.e. reacting directly to tension). Our work showed that the neuromuscular fibers of the nuclear sac type are stimulated by variations in tension as a function of time. Platen (1961) in ocular surgery introduced the notion of traction on the oculomotor muscles. In ‘OpenAnesthesia 2023’ Dennath Chatterjee did a synthesis work in the traction and anesthesia factors. In sports medicine, the dive reflex has been shown to be responsable of arythmia and paroxysmal supraventricular tachycardia. To trigger this reflex, several tests have beeen proposed. A recommandation during clinical examination is the OCR or Carotid glomus massage, with record of EKG and cardiac frequency. Conclusion: The OCR is defined by a reduction in heart rate from direct pressure on the eyeball. Afferent and efferent pathways are known and studied. But the stimulating factor must be studied. We have demontred that is the elongation of neuro-muscular fibers according to the time that excites the phasic fibers. This notion must be integrated both in eye surgery and in tests to highlight the cardiac parasympathetic balance, especially in sports physiology. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

The importance of developmental programming in the beef industry

The beef industry relies on multiple focused segments (e.g., cow-calf, stocker/feeder, and meat packing) to supply the world with beef. Thus, the potential impact of developmental programming on the beef industry needs to be evaluated with regards to the different production traits that drive profitability within each segment. For example, when nutrient restriction of dams occurred early in gestation embryo survival was decreased and the ovarian reserve of heifer progeny was negatively affected. Restriction during mid- to late gestation negatively impacted first service conception rates and pregnancy success of daughters. Even non-nutrient stress has been reported to impact transgenerational embryo development through the male progeny. Primary and secondary muscle fibers form during months two to eight (Days 60–240) of gestation. Therefore, external stimuli (nutrition or environmental) during this window have the potential to decrease the postnatal number of muscle fibers; which has an irreversible impact on animal growth and performance. Nutrient restriction during the last third of gestation resulted in decreased weaning weights, and in some instances decreased dry mater intake, hot carcass weight, and marbling scores. Protein supplementation during late gestation; however, increased weaning weight and ADG to weaning, but progeny of dams restricted in protein in late gestation had greater ribeye area. The importance of developmental programming is recognized; however, its precise application depends on comprehension of its integrated effects across the multiple-focused segments of the beef industry.

Peptide Sequence Variations Govern Hydrogel Stiffness: Insights from a Multi-Scale Structural Analysis of H-FQFQFK-NH2 Peptide Derivatives.

Throughout the past decades, amphipathic peptide-based hydrogels have proven to be promising materials for biomedical applications. Amphipathic peptides are known to adopt β-sheet configurations that self-assemble into fibers that then interact to form a hydrogel network. A fundamental understanding of how the peptide sequence alters the structural properties of the hydrogels would allow for a more rational design of novel peptides for a variety of biomedical applications in the future. Therefore, the current work investigates how changing the type of amino acid, the amphipathic pattern, and the peptide length affects the secondary structure, fiber characteristics, and stiffness of peptide-based hydrogels. Hereto, seven amphipathic peptides of different sequence and length, four of which have not been previously reported, based on and including the hexapeptide H-Phe-Gln-Phe-Gln-Phe-Lys-NH2, are synthesized and thoroughly characterized by circular dichroism (CD), Fourier Transform Infrared (FTIR) spectroscopy, Wide Angle X-ray Scattering (WAXS), Small Angle X-ray Scattering (SAXS), Transmission Electron Microscopy (TEM), and Thioflavin T (ThT) fibrillization assays. The results show that a high amount of regularly spaced β-sheets, a high amount of fibers, and fiber bundling contribute to the stiffness of the hydrogel. Furthermore, a study of the time-dependent fibril formation process reveals complex transient dynamics. The peptide strands structure through an intermediate helical state prior to β-sheet formation, which is found to be concentration- andtime-dependent.

Transcriptomic regulatory analysis of skeletal muscle development in landrace pigs

The development of pig skeletal muscle is a complex dynamic regulation process, which mainly includes the formation of primary and secondary muscle fibers, the remodeling of muscle fibers, and the maturation of skeletal muscle; However, the regulatory mechanism of the entire developmental process remains unclear. This study analyzed the whole-transcriptome data of skeletal muscles at 27 developmental nodes (E33-D180) in Landrace pigs, and their key regulatory factors in the development process were identified using the bioinformatics method. Firstly, we constructed a transcriptome expression map of skeletal muscle development from embryo to adulthood in Landrace pig. Subsequently, due to drastic change in gene expression, the perinatal periods including E105, D0 and D9, were focused, and the genes related to the process of muscle fiber remodeling and volume expansion were revealed. Then, though conjoint analysis with miRNA and lncRNA transcripts, a ceRNA network were identified, which consist of 11 key regulatory genes (such as CHAC1, RTN4IP1 and SESN1), 7 miRNAs and 43 lncRNAs, and they potentially play an important role in the process of muscle fiber differentiation, muscle fiber remodeling and volume expansion, intramuscular fat deposition, and other skeletal muscle developmental events. In summary, we reveal candidate genes and underlying molecular regulatory networks associated with perinatal skeletal muscle fiber type remodeling and expansion. These data provide new insights into the molecular regulation of mammalian skeletal muscle development and diversity.

On the Micro-Stress Fields in Fibre-Hybrid Polymer Composite Laminae with Periodic Microstructure Under Transverse Tension and Transverse Shear Loading

AbstractThis paper investigates the effect of intra-laminar fibre hybridisation, i.e., primary and secondary fibres within a matrix, on the homogenised properties and micro-stress fields in uni-directional polymer composite laminae. The study is focused on S-glass/epoxy laminae which are hybridised with secondary fibres (e.g., polypropylene). Two-dimensional repeating unit cells (2D RUCs) with periodic microstructures are developed to conduct the micro-mechanical analyses under transverse tensile and transverse shear loading conditions. Uni-directional fibre-hybrid S-glass/epoxy laminae with different secondary fibres are studied by varying (a) the periodic microstructure and (b) the material properties of the constituent fibres to assess the effect of such geometric and material variations on the homogenised elastic lamina properties and intra-lamina micro-stress fields. The results show that intra-laminar fibre hybridisation significantly affects the elastic lamina properties and micro-stress fields. Notably, the presence of the secondary fibres significantly increases or reduces the stress fields in the matrix and at the fibre-matrix interfaces (i.e. normal and shears stress components)–depending on the microstructure and the stiffness of the secondary fibres–which could be explored to manipulate the damage modes and thus energy dissipation mechanisms.

Analysis and prediction of compressive and split-tensile strength of secondary steel fiber reinforced concrete based on RBF fuzzy neural network model.

Accurate analysis of the strength of steel-fiber-reinforced concrete (SFRC) is important for ensuring construction quality and safety. Cube compression and splitting tensile tests of steel fiber with different varieties, lengths, and dosages were performed, and the effects of different varieties, lengths, and dosages on the compressive and splitting properties of secondary concrete were obtained. It was determined that the compression and splitting strengths of concrete could be effectively improved by the addition of end-hooked and milled steel fibers. The compressive and splitting strengths of concrete can be enhanced by increasing the fiber length and content. However, concrete also exhibits obvious uncertainty owing to the comprehensive influence of steel fiber variety, fiber length, and fiber content. In order to solve this engineering uncertainty, the traditional RBF neural network is improved by using central value and weight learning strategy especially. On this basis, the RBF fuzzy neural network prediction model of the strength of secondary steel fiber-reinforced concrete was innovatively established with the type, length and content of steel fiber as input information and the compressive strength and splitting tensile strength as output information. In order to further verify the engineering reliability of the prediction model, the compressive strength and splitting tensile strength of steel fiber reinforced concrete with rock anchor beams are predicted by the prediction model. The results show that the convergence rate of the prediction model is increased by 15%, and the error between the predicted value and the measured value is less than 10%, which is more efficient and accurate than the traditional one. Additionally, the improved model algorithm is efficient and reasonable, providing technical support for the safe construction of large-volume steel fiber concrete projects, such as rock anchor beams. The fuzzy random method can also be applied to similar engineering fields.

Bark anatomy of Pteroceltis tatarinowii, Cannabaceae

Summary Pteroceltis tatarinowii, a tertiary relic plant, has a long and fascinating history in China due to its irreplaceable role in traditional papermaking. In this study, the anatomical differences between young and old bark were analysed by light microscopy (LM), fluorescence microscopy (FM), and polarized light microscopy (PLM). Both the young and old bark contain periderm, cortex, and phloem. In the non-conducting phloem, the curved radial phloem rays were perpendicular to bands of sieve-tube elements and axial parenchyma cells, forming a net-like pattern. Primary phloem fibres only occurred in young bark, and both primary and secondary phloem fibres contained a gelatinous layer (G-layer). Transmission electron microscopy (TEM) showed that the thickness of the G-layer in the primary phloem fibres was about 1.5–4 times higher than that of the secondary phloem fibres. The thick G-layer might be an important potential reason for the absorption of ink by paper made from P. tatarinowii phloem fibres, due to the good water absorption of the gelatinous layer.

Production of derivatives from wheat straw as reinforcement material for paper produced from secondary fibers

Nowadays, a high percentage (> 50%) of the paper produced in Europe uses recovered paper (secondary fibers) as raw material. In order to improve the mechanical properties of the paper produced, different kinds of additives are usually incorporated into the paper. Emerging renewable materials based on agricultural or forest residues, such as cellulose nanomaterials, have recently proved good capacities as reinforcing agents for different applications. In this work, pulp from wheat straw with a content of cellulose nanomaterial has been produced and tested as a mechanical reinforcing agent for paper production. A soda semi-chemical process was applied for the delignification of straw, to produce pulp with high cellulose content. Posteriorly, pulps with cellulose nanofibers were obtained in a high-pressure homogenizer, applying three different pretreatments to the cellulose pulp (acid hydrolysis, enzymatic hydrolysis and thermal treatment with glycerol) in order to facilitate the obtention of cellulose nanomaterial. Handsheets of paper were prepared from two sources of secondary fiber (fluting paper and old corrugated containers), adding different percentages of wheat straw derivatives (0, 3.5, 5 and 7%). The fibers' morphology and the papers' mechanical properties were investigated. Noticeable improvement rates (up to 25%) were observed for some mechanical properties of paper containing nanocellulose produced after the enzymatic and acid pretreatments. The quality of the secondary fibers source also affected the improvement rates achieved, with higher percentage changes for the lower-quality recycled paper.

Production of bio-based paper coating made with the addition of eggshell powder

A chitosan based coating was prepared where eggshell powder was added. Eggshell is a product that appears in large numbers in everyday life, so it has great potential as waste, which can be used to turn it into a valuable material. Cellulose sheets were made from secondary fiber, and after coated with the chitosan based solution to investigate the properties of the sheets. The results of the treated handsheets were compared with the results of the control sheet. The control sheets were compared with 4 different type of paper: coatings of chitosan with 5wt% and 10wt% eggshell powder, only chitosan coating, and paper where eggshell powder was added to the paper pulp. The use of the eggshell powder as an additive in the coating would be a promising material, because it can improve in a large extent the water resistance and the air barrier properties of the paper.

Mechanism of Action and Validation of the Traditional Medicinal use of Grewia Tenax Fruits in Sudan to Encounter Iron Deficiency Anemia

Introduction: In Sudan, Grewia tenax fruits, are known commonly as Goddaim. The fruit’s pericarp is used traditionally for a long time as a juice or a porridge to treat iron deficiency anemia (IDA). Traditional Goddaim users have a very strong belief in its effectiveness. However, the pattern of hemoglobin improvement follows an initial fast increase followed by a decline upon continuing its use. Some previous studies have attributed its effect to high iron content, while the iron quantity was too small. This work attempts to find an explanation for its mechanism of action by screening the fruit extract and its respective fractions for secondary metabolites, minerals, vitamins, and fibre. Methods: Entailed three methodologies: Chemical analysis to identify quantified minerals, ascorbic acid and non-digestible fibers, Phytochemical Analysis to separate and identify secondary metabolites using high-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS-MS technique), and estimation of radical scavenging activities of crude fruit extract and its respective chloroform and ethyl acetate fractions by inhibition of the 2,2-diphenylpicrylhydrazyl (DPPH). Results: Ascorbic acid and indigestible fibres were revealed in the aqueous extract. Secondary metabolites were flavonoids (e.g., quercetin, kaempferol), organic acids (e.g., ferulic acid, chlorogenic acid), β-carboline alkaloids (e.g., 3-hydroxy-tetrahydroharman) identified in the chloroform, and ethyl acetate fractions. The in vitro antioxidant activity of G. tenax fruit extract was confirmed spectrophotometrically. Conclusion: It can be concluded that the initial enhancement of iron absorption through ascorbic acid and fibres, followed by iron uptake inhibition, could be explained by iron chelation by the chelators in the fruits. This paradoxical effect may qualify G. tenax fruits as a safety gauge for improving haemoglobin levels without compromising iron excess once iron stores are filled by keeping the oxidative stress in check. This may present G. tenax fruits as a good and safe remedy that optimizes the treatment of IDA.

Investigation of acoustic, mechanical, thermal, and moisture properties of milled alkali‐treated coconut tree secondary flower leaf stalk fiber‐reinforced polymer composite

AbstractThe current research study centers on exploring natural fibers due to the increasing need for sustainable and eco‐friendly alternatives in various industries. In India, where coconut trees are widely grown for their tender coconuts and by‐products, the leftover fruit leaf stalks become agricultural waste once the coconut is harvested from the trees. So this research work involves the development of composite materials with natural fiber components by using unsaturated polyester resin (UPR) as the matrix material along with alkali‐treated coconut tree secondary flower stalk fiber (ACSF) for reinforcing. The composite materials were formed using the compression molding technique with different weight compositions of 20%, 30%, and 40% of ACSF and 80%, 70%, and 60% of UPR, respectively. From the results, the 30ACSFC reveals a maximum value of 42 N/mm2, 58 N/mm2, 10 kJ/m2, and 48 HD in flexural, tensile impact, and hardness tests, respectively. In the water absorption analysis, 20ACSFC had observed a lower moisture content, which explains the low weight percentage of ACSF in the composite. From the TGA analysis, 30ACSFC had a residual mass of 18% due to the significant change in the cellulose because of alkali, leading to strong adhesion in the composition matrix. The SAC analysis reveals that at the peak and trough levels of frequency, varying the composition of composite materials leads to improved sound absorption coefficients that surpass the performance of the 30ACSFC composite. The SEM study was carried out to identify the mechanism of failure in the elongated specimens of the tensile test, which was based on the phenomena of matrix crack, fiber pull‐out, fiber shearing, void and interfacial bonding, and de‐bonding. These results indicate the possibility of creating lightweight composites with improved strength and stiffness, making them suitable for use in roof panels, door panels, insulation, and other related applications. The incorporation of ACSF as a reinforcing material introduces new prospects for sustainable and environmentally friendly composite materials, showcasing promising mechanical and thermal properties.Highlights Enhanced mechanical strength: Evaluation of tensile strength, flexural strength, and impact resistance showcases how ACSF reinforcement improves the composite's load‐bearing capacity and durability. Effective acoustic dampening: A study of sound absorption and transmission properties reveals the composite's potential in noise reduction applications, such as architectural acoustics and automotive soundproofing. Thermal insulation potential: An assessment of thermal conductivity and expansion helps identify whether the composite is suitable for applications requiring enhanced insulation or efficient heat transfer. Moisture resistance and stability: An analysis of moisture absorption and dimensional changes informs the composite's suitability for humid environments, ensuring its resistance to degradation and maintaining the dimensional stability.