Composition Characteristics Research Articles

Association of a composite trait for anthropometrics, adiposity and energy expenditure with cardiometabolic diseases: An age-stratified cohort and genetic risk score analysis.

Various anthropometric measures capture distinct as well as overlapping characteristics of an individual's body composition. To characterize independent body composition measures, we aimed to reduce easily-obtainable individual measures reflecting adiposity, anthropometrics and energy expenditure into fewer independent constructs, and to assess their potential sex- and age-specific relation with cardiometabolic diseases. Analyses were performed within European ancestry participants from UK Biobank (N = 418,963, mean age 58.0 years, 56% women). Principal components (PC) analyses were used for the dimension reduction of 11 measures of adiposity, anthropometrics and energy expenditure. PCs were studied in relation to incident type 2 diabetes mellitus (T2D) and coronary artery disease (CAD). Multivariable-adjusted Cox regression analyses, adjusted for confounding factors, were performed in all and stratified by age. Genome-wide association studies were performed in half of the cohort (N = 156,295) to identify genetic variants as instrumental variables. Genetic risk score analyses were performed in the other half of the cohort stratified by age of disease onset (N = 156,295). We identified two PCs, of which PC1 reflected lower overall adiposity (negatively correlated with all adiposity aspects) and PC2 reflected more central adiposity (mainly correlated with higher waist-hip ratio, but with lower total body fat) and increased height, collectively capturing 87.8% of the total variance. Similar to that observed in the multivariable-adjusted regression analyses, we found associations between the PC1 genetic risk score and lower risks of CAD and T2D [CAD cases <50 years, odds ratio: 0.91 (95% confidence interval 0.87, 0.94) per SD; T2D cases <50 years, odds ratio: 0.76 (0.72, 0.81)], which attenuated with higher age (p-values 8.13E-4 and 2.41E-6, respectively). No associations were found for PC2. The consistently observed weaker associations of the composite traits with cardiometabolic disease suggests the need for age-specific cardiometabolic disease prevention strategies.

Thermal performance of a novel hybrid heat pipe with composite heat transfer characteristics

Considering the capillary threshold of oscillating heat pipes (OHP), a novel hybrid heat pipe (HHP) was designed with channels with hydraulic diameters that alternately exceed and fall below this threshold, parallelly arrayed within a unified copper substrate. This technology attains a comprehensive heat transfer performance within the HHP, seamlessly transitioning from pure phase change heat transfer to hybrid pulsating flow heat transfer to effectively accommodate the escalating demands of heat load. Performance and visualization are used to analyze the operational characteristics of HHP. The results indicate that the HHP mainly transfers heat through the phase change in the large channels in lower heat input, while the working fluid in the small channels remains calm. Once the heat input is sufficient, the geyser boiling in the large channels and the liquid slug pulsating in the small channels jointly carry out heat transfer. Furthermore, the liquid content in the large and small channels can be adaptively adjusted to each other. The high-speed liquid in the small channels can be squeezed into the large channels to ensure the sufficient pulsating space and achieve efficient heat transfer under high heat input. In addition, the operation of the HHP can be significantly impacted by the filling ratio (FR). In the phase change stage, the FR of 47.6 % can be considered as the turning point. After transitioning to the hybrid pulsating flow stage, the HHP with low FR can get a better performance. This new type of heat pipe with gradually changing operation characteristics may be critical to solve thermal problems in variable heat load domain.

Enhancing nutritional composition and aroma characteristics of kiwifruit wines through indigenous non-Saccharomyces yeast extracellular extract treatment

To unlock the potential of strains for further enhancing the aromatic complexity of kiwifruit wines while avoiding undesirable flavors, indigenous non-Saccharomyces yeast extracellular extract treatment for fermentation was established. The extracellular extract from Zygosaccharomyces rouxii, Pichia kudriavzevii, and Meyerozyma guilliermondii were prepared and supplemented individually or in pairs to the kiwifruit wine fermentation system. Subsequently, the changes in physicochemical properties, antioxidants, and volatile characteristics of kiwifruit wines produced by different protocols were comprehensively evaluated, and the major aroma descriptors affecting sensory acceptability were analyzed by sensory evaluation and partial least squares regression. The results showed that extracellular extract treatment significantly improved the organic acids and monomeric phenols content, antioxidant capacity, and volatiles of kiwifruit wines. Compared to Sc, the increase in esters and alcohols, along with the decrease in aldehydes and acids in Pk-Zr and Mg-Zr, enhanced the aromatic complexity while reduce grassy and fungal flavors, resulting in higher sensory acceptability.

Effect of Carbon Nanotubes Functionalization on the Chemical Composition and Electrochemical Characteristics of Composites with Layered Potassium Manganese Oxide

The influence of pretreatment of multiwalled carbon nanotubes (MWCNTs) in oxidizers (solutions of H2O2 and HNO3) on the structure and electrochemical properties of composites with layered potassium-manganese oxide (KxMnO2) was studied. Composites were obtained by soaking carbon nanotubes in an aqueous solution of KMnO4 at 60 °C. The electrochemical performance of the composites was evaluated by cyclic voltammetry and galvanostatic charge‒discharge methods. It has been established that stronger oxidation of the MWCNTs surface at the functionalization stage leads to a noticeable increase in the reaction rate as well as the optimal potassium content in the KxMnO2 composition, which provides higher capacitive characteristics of the composite (a maximum specific capacitance of 150 F g−1 and a rate capability of 43% with increasing density current from 0.1 to 2.0 A g−1). The resulting composites are promising active components for increasing the capacitive characteristics of conductive carbon black (CB). Compared with an electrode based only on CB, electrodes based on a combination of the composite and CB at a mass ratio of 1:1 showed specific capacitance values approximately 1.5 to 3 times greater, as well as a twofold increase in rate capability (from 35 to 70%) in the range of discharge current density 0.1 to 2.0 A g−1.

The effect of the isocyanate trimerisation catalyst on the chemical composition and strength characteristics of polyurethane-polyisocyanate foams

Nowadays polyurethane-polyisocyanurate (PIR) foams are in a wide use as structural and thermal insulation materials. Isocyanate trimerisation catalysts for foams synthesis have low selectivity in terms of isocyanurate formation. As a consequence, a significant number of target (primary) and (secondary) chemical processes occur during the synthesis of PIR foams. We estimated the dependence of isocyanate group consumption for the formation of the main primary and secondary products on composition isocyanate index by methods based on the internal standard. Indeed, with an increase in the isocyanate index, the conversion of isocyanate to isocyanurate decreases significantly. The paper examines the influence of trimerisation catalyst type on chemical composition and strength characteristics of PIR foams. Hence, catalysts based on organic salts of alkali metals are more selective to the isocyanate trimerisation process than tertiary amines and derivatives of quaternary ammonium bases.

Investigation of microstructural and mechanical characteristics of Al-ZrO2 composites fabricated by stir casting

Investigation of microstructural and mechanical characteristics of Al-ZrO2 composites fabricated by stir casting

The microstructure and mechanical property of W-TiC/Ti composites via chemical-mechanical milling method

Carbide dispersion strengthened W(CDS-W) has attracted much attention as a plasma-facing material (PFM). However, the carbide tends to segregate at W grain boundaries and has poor interface properties with W due to the large difference in the bond structure. In this work, nanometer Ti was added to improve the performance of the W/TiC interface, and nanoscaled W-TiC-x%Ti (x=0.1,0.5 and 1.0) composites were prepared by chemical-mechanical milling and ordinary sintering method. The effects of Ti on powder morphology, phase composition, microstructure and mechanical properties were systematically investigated using XRD, SEM, EDS, TEM and HADDF technologies. Simultaneously, the existence form and distribution of Ti elements, and W/TiC interface characteristics of powders and composites were analyzed. Moreover, the microstructure evolution and strengthening mechanism were preliminarily discussed. Results show that the W-TiC/Ti powder has an obvious core-shell multilayer structure with a particle size range of 50-120 nm. The addition of Ti exists in the forms of TiC, Ti, and TiO2, and has no effect on the morphology and phase composition. Besides, the phase transformation and solution-precipitation of the Ti-added occurs during the sintering process. Part of Ti precipitates on the W/TiC surface to form Ti rich region, which significantly promotes the dispersion of TiC and improves the W/TiC interface, as well as prevents the growth of W grains, and the average grain size is 2.90 μm. Moreover, the orientation relationship of [013]( 00)TiCFCC||[ 13]( 0)WBCC exists at the W/TiC interface, especially the coherent phase interface is formed. The tensile strength and microhardness at room temperature are 520 MPa and 850 HV0.2, respectively, which is attributed to the synergistic effect of fine-grained strengthening, dispersion strengthening and interface strengthening. This work can provide a new strategy and direction for preparing high-performance CDS-W materials.

Sustainable lignocellulosic mediterranean biocomposites: Thermogravimetric analysis, mechanical performance, morphological and comparative study

Utilizing accessible agricultural waste to create sustainable materials is a potentially beneficial attempt toward developing better bio-products and a more sustainable socioeconomic environment. Accordingly, this work aims to investigate the mechanical performance enhancement and/or deteriorations as well as morphological and thermal characteristics of certain Mediterranean lignocellulosic fiber composites considering various reinforcement conditions. Several composites of polypropylene pomegranate peel powder (PG) and short corn leaves (CL) were designed and fabricated with various reinforcement conditions to demonstrate their potential characteristics. Moreover, the experimental results of this work were compared with commonly used fiber/PP composites worldwide to demonstrate their appropriateness for producing bio-based composites suitable for various applications. The investigations included determining the tensile strength, tensile modulus, elongations at break properties under various reinforcement conditions, as well as revealing the thermal properties of the fibers to expose their suitability for such bio-based composites to improve utilizing such available waste of fibers into useful materials for various mechanical components. Thermal gravimetric analysis (TGA) and derivative thermal gravimetric analysis (DTG) were also carried out to examine thermal stability and to distinguish the maximum degradation temperature (Tmax) of the cellulosic fiber compositions. The outcomes revealed that both types of fibers, pomegranate peel powder and short corn leaves, had positive impacts on the tensile strength and modulus of PP regardless of the weight percentage. The 40 wt% of corn leaves displayed the best improvement in the strength (+29 %) and modulus (+17 %). The 40 wt%, CL-PP reached tensile modulus of 1589.5 MPa, whereas the best modulus for the PG-PP was 1399.4 MPa at 30 wt%. When comparing the tensile strength and modulus of PG/PP and CL/PP composites with those reported in the literature, these composites demonstrated superior tensile properties relative to thirteen other types documented. Regarding the thermal analysis, PG and CL fibers could withstand the processing temperature without degradation, which enables them to be feasibly utilized in bio-based composites to enhance the development of green bio-products. When it comes to the morphological analysis, it was observed that there was a good adhesion between PP and CL, which interprets the enhancement tensile properties.

Review on Tribological and Machining Characteristics of Kevlar Composites

Review on Tribological and Machining Characteristics of Kevlar Composites

Tribological, mechanical and microstructure characteristics of hybrid aluminium matrix composite containing titanium carbide (TiC) and graphite particles

The present study emphasize on the characterization and microstructure evaluation of aluminium composite with different weight fraction of constituents. These composites were produced by incorporating titanium carbide and graphite particles in the aluminium matrix through stir casting technique. The composites were characterized by evaluating the micro hardness, density, tensile strength, peak elongation and impact strength. Scanning electron microscopy and X-ray diffraction tests were performed to investigate uniform dispersion of the reinforcement particles in the matrix. It is evident that the addition of reinforcement particles with aluminium matrix yielded an increase in micro hardness and density by 62.82% and 7.05% respectively when compared to matrix. Tensile tests exposed that there was improvement in ultimate strength from 170 to 239.11 MPa while the elongation was dropped to 7.1%. The microscopic study of the specimen explored the plastic deformation through existence of dimples, ridges in the wrecked surfaces.

Characteristics of forest understory herbaceous vegetation and its influencing factors in biodiversity hotspots in China

Forest ecosystems, especially within biodiversity hotspots, heavily rely on the often-overlooked understory herbaceous communities (USHC) for their structural integrity and ecological functions. Because of their modest stature, these communities have garnered insufficient attention from researchers. Therefore, in this study attention is focused on USHC, which attempts to fill this research gap. To achieve this, we established 105 sample plots in 2022 within forest ecosystems situated in the biodiversity hotspot of southwest China. Our investigation unveiled a rich biodiversity tapestry, identifying 424 plant species from 108 families and 284 genera. Notable were the 217 herbaceous species identified in the understory layer, representing 67 families and 163 genera. These understory herbaceous species accounted for 51.2 % of the overall species count. Through a detailed analysis, the sample plots were categorized into eight distinct communities using a two-way indicator species analysis. These communities exhibited diverse variations in species composition, diversity, biomass, and nutrient characteristics. Notably, community I (Eucalyptus robusta Smith + Rubus corchorifolius L. f. + Alternanthera philoxeroides (Mart.) Griseb.), V (Camptotheca acuminata Decne + Rubus parkeri Hance + Iris tectorum Maxim), VIII (Platycladus orientalis (L.) Franco + Viburnum dilatatum Thunb. + Cyclosorus interruptus (Willd.) H. Ito) stood out for their exceptional species diversity and productivity. Moreover, correlation analyses highlighted the substantial impact of topographic and soil factors on USHC. Altitude, soil water content, and total carbon content emerged as the primary determinants of species diversity. Biomass demonstrated close associations with total soil carbon and nitrogen. Furthermore, the nutrient characteristics displayed significant correlations with soil nutrient contents. These findings underscore the critical importance of prioritizing USHC attention in forest conservation and management strategies within biodiversity hotspots. The implications strongly advocate for the inclusion of these communities in planning and decision-making processes, emphasizing their pivotal role in maintaining structural and functional diversity in ecosystems.

A Study of Dimethyl Ether-Steam Coinjection Using a Large-Scale Physical Model

Summary Dimethyl ether (DME) as a water-soluble solvent has been studied as a potential additive to steam for improving the energy efficiency of steam-assisted gravity drainage (SAGD). The main objective of this research was to study in-situ flow characteristics and energy efficiency of DME-SAGD using a large-scale physical model. Results from DME-SAGD were compared with the control experiment of SAGD with no solvent injection using the same experimental setup. The main novelty of this research lies in the experimental data that demonstrated enhanced bitumen drainage by DME-SAGD in comparison with SAGD. The experiment was conducted in a cylindrical pressure vessel with a diameter of 0.425 m and a length of 1.22 m, which contained a sandpack with a porosity of 0.34 and a permeability of 5.0 darcies. The DME-SAGD experiment used a DME concentration of 10 mol% and a steam coinjection rate of 27.6 cm3/min [cold-water equivalent (CWE)] at 3000 kPa. Temperature distributions within the sandpack, along with injection and production histories, were recorded during the experiment. Subsequently, numerical simulations were performed to history match the experimental data, and the calibrated simulation model was used to analyze the details of compositional flow characteristics. Results showed that the 10 mol% DME-SAGD experiment yielded a recovery factor (RF) of 92.7% in 4.2 days, and the SAGD experiment yielded an RF of 68.6% in 6.0 days; for both experiments, the first 2 days were the preheating and the steam-only injection (SAGD) stages. The peak rate of bitumen production was 43.8 mL/min in the DME-SAGD experiment, which was more than twice greater than the peak rates observed in the SAGD experiment. The substantially increased rate of bitumen production resulted in a cumulative steam/oil ratio in DME-SAGD that was less than half of that in SAGD. Analysis of experimental results indicated that the solubility of DME in the aqueous and oleic phases caused different flow characteristics between DME-SAGD and SAGD. For example, the oleic and aqueous phases were more uniformly distributed in the sandpack in the former. Simulations indicated that DME-SAGD had a greater distribution of grid-scale inverse mobility ratio and increased oleic-phase mobilities in comparison with SAGD.

Simulation of the Process of Temperature Field Changing of a Zr–1%Nb Zirconium Alloy Billet During Equal-Channel Angular Pressing

Using mathematical modeling in the QFORM software package, the data on the temperature distribution of a billet made of a zirconium alloy E110 (Zr–1%Nb) in its longitudinal and transverse sections during an equal-channel angular pressing (ECAP) were obtained. The initial data on the geometric parameters of the billet and the die of the ECAP unit are presented, and the conditions for carrying out the process of severe plastic deformation, as well as the chemical composition and physical characteristics of the Zr–1%Nb alloy necessary for carrying out the computational modeling are described. The values of the billet temperature were determined for the calculated moments of the passage of the billet through the junction of the die channels, which corresponded to 25%, 50%, and 75% of its length. It is shown that during the ECAP process at a given pressing speed, in the section corresponding to the junction of the matrix channels, an increase in the billet temperature relative to its initial heating occurred by an amount of about 10 ºC.

Long-term Chinese milk vetch incorporation promotes soil aggregate stability by affecting mineralogy and organic carbon

Soil aggregates profoundly impact soil sustainability and crop productivity, and they are influenced by complex interactions between minerals and organics. This study aimed to elucidate the alterations in mineralogy and soil organic carbon (SOC) following long-term green manure incorporation and the effect on soil aggregates. Based on 5- and 36-year field experiments, surface soil samples (0-20 cm) were collected from Alfisol and Ferrisol soils subjected to rice-rice-winter fallow (CK) and rice-rice-Chinese milk vetch (MV) treatments to investigate aggregate stability, mineralogy, SOC composition, and soil microstructural characteristics. The results showed that high clay-content Ferrisol exhibited greater aggregate stability than low clay-content Alfisol. The phyllosilicates in Alfisol primarily comprised illite and vermiculite, whereas those in Ferrisol with high-content free-form Fe oxides (Fed) were dominated by kaolinite. Additionally, the clay fraction in Ferrisol contained more aromatic-C than the clay fraction in Alfisol. The 36-year MV incorporation significantly increased the Ferrisol macroaggregate stability (9.57-13.37%), and it also facilitated the transformation of vermiculite into kaolinite and significantly increased the clay, Fed, and aromatic-C contents in Ferrisol. Backscattered electron (BSE)-scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS) revealed a compact aggregate structure in Ferrisol with co-localization of Fe oxides and kaolinite. Moreover, the partial least path model (PLS-PM) revealed that clay content directly improved macroaggregate stability, and that kaolinite and Fed positively and directly affected clay or indirectly modulated clay formation by increasing the aromatic-C levels. Overall, long-term MV incorporation promotes clay aggregation by affecting mineral transformation to produce more kaolinite and Fe oxides and retain aromatic-C, and it ultimately improves aggregate stability..

Synergistic adsorption–photocatalytic degradation of the emerging contaminant hydroxybenzotriazole by a 3D sponge-like easy separation polypyrrole/TiO2 composite

Herein, a 3D sponge-like polypyrrole/TiO2 (Ppy-TiO2) composite aerogel was developed for the first time to remove hydroxybenzotriazole (HOBt) from water. Mesoporous TiO2 was prepared via a sol–gel method, and then the Ppy-TiO2 composite hydrogel was prepared by oxidative polymerization and converted to aerogel by freeze-drying. The morphological, compositional, and surface characteristics of the prepared materials were detailly characterized. The characterization studies revealed that pure anatase mesoporous TiO2 nanoparticles were successfully prepared and incorporated into amorphous 3D Ppy with a porous chain-like network structure. Coupling Ppy and TiO2 extended the light absorption to the visible region and decreased the electron/hole recombination rate. The performance studies revealed that the Ppy-TiO2 composite has higher adsorption and photocatalytic activities than the sum of the individual components. Optimum performance was obtained at pH 5.3 using 0.25 g/L of the Ppy-TiO2 composite with a Ppy: TiO2 mass ratio of 1:1. The intermolecular hydrogen bonding was pivotal in the adsorption process which was multilayer. The degradation of HOBt occurs primarily by holes, then superoxide anion radicals. The total organic carbon (TOC) analysis showed a 90% reduction in carbon content after 30 min of treatment. The toxicity study indicated that the photocatalytic process decreased the toxicity of the HOBt solution. The synergism between adsorption and photocatalysis, easy separation, and reusability promote the application of Ppy-TiO2 composite aerogel for water treatment.

Influence of multigenerational and living-alone households on high fat, sugar or sodium (HFSS) food consumption pattern in aging population

ObjectivesTo investigate the correlation between household composition and consumption of different groups of high fat, sugar or sodium (HFSS) among older persons in Thailand. Study DesignThis study used cross-sectional data from the 2021 population-based survey called the Health Behavior of Population Survey. MethodsData from this study were drawn from 39,384 sampled Thai older persons age 60 years or over. A food frequency questionnaire was used to collect information about frequency of HFSS food consumption, household composition, and socio-demographic characteristics. Binary logistic regression was performed to investigate correlations between household composition and food consumption. ResultsMore than three in five older Thais lived in a multigenerational home. The probabilities of consuming high-fat food, fast food, and snacks among older persons who lived with working-age person(s) and child(ren)/adolescents were much higher than for those living alone. Older persons who lived alone had the highest probability of consuming instant food, compared with other types of household composition. Participants who lived with child(ren)/adolescents only or with working-age person(s) only (p≤0.01) and child(ren)/adolescents only (p≤0.001) were more likely to consume sugar-sweetened beverages (SSB). ConclusionsThe findings point to life course interventions to discourage HFSS consumption across generations. Social interventions and public policy aiming at increasing intergenerational interactions could be beneficial for healthier diets for not only older persons but also across generations.

Nutrient Composition And Sensory Evaluation Of Sorghum Based Complementary Food Fortified With Soybean, Carrot And Crayfish

The nutritional composition and sensory characteristics of sorghum-based complementary food fortified with soybean, carrot and crayfish at different substitutional levels were evaluated using standard analytical procedures. The results revealed that moisture,ash,fat,fibre,protein and carbohydrate content values range from 7.73% to 13.07%, 1.84% to 4.66%, 39.48% to 44.02%, 0.02% to 2.01%, 13.59% to 24.51% and 16.31% to 27.44% respectively. The selected minerals showed that calcium, zinc, magnesium, manganese, and iron varied from 1.61 to 15.56mg/100g, 0.05 to 4.71mg/100g, 3.51 to 8.80mg/100g, 0.22 to 7.78mg/100g and 0.02 to 6.68mg/100g respectively. Vitamin A showed an appreciable amount in the sample with the inclusion of carrot.Values obtained met the Codex Alimentarius Commission Guidelines for formulated complementary foods for older infant and young children. The sensory properties revealed that sample E (60% sorghum, 25% soybean, 10% carrot and 5% crayfish) was most preferred and this has provided a basis for the development of an acceptable complementary food that can provide the needed protein and other nutrients, thereby combating protein energy malnutrition in infants

The gut microbiome without any plant food? A case study on the gut microbiome of a healthy carnivore

Objective The carnivore diet is a ketogenic diet based exclusively on the consumption of food of animal origin. While the impact of various diets on the gut microbiome is extensively documented, the effects of a carnivore diet remain unclear. To address this gap, we conducted a pilot study on the gut microbiome of an individual following a carnivore diet and compared it with that of a subgroup of healthy individuals. Methods A stool sample was collected from a healthy 32-year-old male adhering to a carnivore diet and was sequenced using 16S DNA Amplicon Sequencing. The results were then compared to those from three control groups possessing similar anthropometric characteristics and differing in their frequency of meat consumption. Results The gut microbiome of the carnivore was dominated by the phylum Firmicutes and the genera Faecalibacterium, Blautia, unspecific Lachnospiraceae, Bacteroides, and Roseburia—bacteria known for fiber degradation. Furthermore, neither alpha- nor beta-diversity, nor the functional capacity of the gut microbiome, showed differences when compared to the control groups. Additionally, the gut microbiome of the carnivore showed the least similarities with the microbiome of the cohort consuming meat on a daily basis. Conclusions In our study, we showcase the compositional and functional characteristics of the gut microbiome in an individual on a carnivorous diet, finding no differences in comparison to a control cohort. Further research is needed to investigate the short- and long-term impacts of a carnivorous diet on gut health through cross-sectional and longitudinal studies. Significance statement To the best of our knowledge this is the first study to report on the composition of the gut microbiome of a person adhering long-term to the carnivore diet.

Thickness-controlled HsGDY/N-doped double-shell hollow carbon tubes for broadband high-performance microwave absorption

With the increasing deterioration of the electromagnetic environment, it is important to develop new and efficient electromagnetic wave-absorbing materials. In this work, bilayer hollow HsGDY/NC nanotubes with controllable thickness are constructed by introducing high conductivity polydopamine (PDA) and hydrogen-substituted graphdiyne (HsGDY) followed by the etching and carbonization. Subsequently, the effects of the composition, coating order, and structural characteristics of nanotubes on the electromagnetic parameters are thoroughly investigated, thereby analyzing the microwave absorption mechanism. The impedance matching of HsGDY/NC is optimized by changing the thickness of NC layer, while utilizing unique multi-heterogeneous interfaces and hierarchical conductive structures that enhance the interface polarization and conductive loss. As a result, HsGDY@NC-3 displays the optimal absorbing performance with an effective absorption bandwidth (EAB) of 7.8 GHz (10.1–17.9 GHz) and a minimum reflection loss (RLmin) of −47.18 dB at the filler content of only 11 %. This work broadens the application scopes of HsGDY and provides a novel insight into the design of lightweight, high-efficiency, and wide-frequency microwave absorbers, which is expected to be a potentially effective microwave-absorbing material.

Development of Natural Fiber Reinforced Polymer Matrix Composites: A Critical Review

AbstractFiber reinforced composites are made by reinforcing fibers in a polymeric matrix and shaping them to fit. Natural fibers, on the other hand, such as jute sisal, hemp, flax etc. are increasingly commonly utilized as reinforcements and perform similarly to artificial fibers. Man‐made fibers like as carbon, glass, and kevlar are utilized as reinforcements in the start and have shown to be the best in terms of characteristics, reinforcing capacity, and usefulness. Research investigations also show that when man‐made and natural reinforcements are combined in a hybrid form, the composite characteristics increase significantly. The composite material obtains all of the better qualities of individual fibers as a result of this combination, and when the composite is subjected to varying loads, each fiber gives its own maximal resistance. The chemical and physical properties are further enhanced by including particular reinforcements into polymer matrix composites, which provide whole new features (which has transformed the aerospace, marine, defence, and automobile industry). As a result, the composite would be better in all attributes. The current study provides a thorough examination of the different challenges concerning the synthesis and mechanical characterization of natural fiber reinforces hybrid polymer composites. Future difficulties, as well as areas of use for polymer matrix composites, have been investigated that may aid in the elimination of plastic waste and the reduction of environmental pollution.