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The concentration of microplastics (MPs) in two important Hungarian freshwater habitats was determined in the size range of 50 μm–1 mm. Lake Balaton (LB) is the largest shallow lake in Central Europe, with a significant role in recreation and tourism. Its main inflow, the Zala River, enters the lake through an artificially constructed wetland, the Kis-Balaton Water Protection System and its catchment area (KB), which helps preserve the water quality of the lake. From these two areas, 15 samples were taken with an in situ filtration sampling method. After preparation, the samples were analyzed automatically by FT-IR microscopy. All samples, from both areas, contained MPs; the dominant microplastic (MP) shape was the fragment, while the most frequently polymer types were polyethylene, polypropylene and alkyd. Small MPs were dominant in both areas; around 90% of the MPs were smaller than 500 μm. On average, LB contained more MPs (21.0 ± 12.5 MPs/m3) compared to the KB, which presented an average concentration of MPs of 7.8 ± 5.9 MPs/m3. In the examined areas, two potential MP sources were determined, i.e., treated wastewater and road traffic. The importance of tourism should also be further investigated.

Carbon nanotubes (CNTs) have been regarded as emerging materials in various applications. However, the range of biomedical applications is limited due to the aggregation and potential toxicity of powder-type CNTs. To overcome these issues, techniques to assemble them into various macroscopic structures, such as one-dimensional fibers, two-dimensional films, and three-dimensional aerogels, have been developed. Among them, carbon nanotube fiber (CNTF) is a one-dimensional aggregate of CNTs, which can be used to solve the potential toxicity problem of individual CNTs. Furthermore, since it has unique properties due to the one-dimensional nature of CNTs, CNTF has beneficial potential for biomedical applications. This review summarizes the biomedical applications using CNTF, such as the detection of biomolecules or signals for biosensors, strain sensors for wearable healthcare devices, and tissue engineering for regenerating human tissues. In addition, by considering the challenges and perspectives of CNTF for biomedical applications, the feasibility of CNTF in biomedical applications is discussed.

A large amount of the polypropylene (PP) produced worldwide is used in the form of fibers. In this work, a new modification route for talc and PP is investigated, which is based on the in situ polymerization of a silane–siloxane monomer mixture on the surface of talc particles or PP pellets, respectively. The obtained modified talc and PP samples were used for the development of PP-talc composite drawn fibers. Tensile tests, thermogravimetry (TGA), and X-ray diffraction (XRD) were used for the characterization of the materials. It was observed that such a modification procedure resulted in the exfoliation of some talc particles. Enhanced tensile strength was observed for composite drawn fibers of a low talc content (1% with respect to PP) and a low modifier content (2% with respect to talc), while co-aggregation of talc and silicone may occur at high silicone and talc contents, resulting in the inferior mechanical performance of the corresponding composites. It was concluded that the produced silicone polymer simultaneously acts as a modifier, antioxidant, and compatibilizer. The proposed modification route is promising and should be further optimized.

Water damage is one of the major distresses of asphalt pavements. Existing methods for investigating the water stability of asphalt mixtures rely primarily on static water test methods, the tensile strength ratio (TSR) test, and the retained Marshall stability (RMS) test, which evaluate the strength and stability loss after freeze-thaw damage or hot water immersion, respectively. However, these methods do not accurately replicate the actual dynamic water damage conditions to pavement. Therefore, in this study, a variety of damage conditions, including static water conditions and dynamic water pressure conditions, were used to investigate the effects of lignin fibers (LFs), polyester fibers (PFs), and polypropylene fibers (PPFs) on the water stability of asphalt mixtures. First, three fibers-enhanced SMA gap-gradation asphalt mixtures were designed. Then, TSR and RMS were measured under traditional static water damage conditions and new dynamic water pressure damage conditions to evaluate the effect of fiber types on the water stability of asphalt mixtures. Finally, the void rate of asphalt mixtures and its changes under dynamic water damage conditions were further revealed with the help of CT scanning technique. Results showed that, among these three types of fibers, PFs-enhanced asphalt mixture exhibited excellent stability under both static and dynamic water conditions, and the CT scanning test also indicated that the PFs can significantly reduce the increase rate of voids in asphalt mixtures after dynamic water pressure damage. This study identified the potential of incorporating suitable type of fiber to enhance the performance of asphalt mixture under dynamic water pressure damage.

Determining the mechanical properties of a composite material represents an important stage in its design and is generally a complicated operation. These values are influenced by the topology and geometry of the resulting composite and the values of the elastic constants of the components. Due to the importance of this subject and the increasing use of composite materials, different calculation methods have been developed over the last fifty years. Some of the methods are theoretical, with results that are difficult to apply in practice due to difficulties related to numerical calculation. In the current paper, using theoretical results offered by the homogenization theory, values of engineering elastic constants are obtained. The finite element method (FEM) is used to determine the stress and strain field required in these calculations; this is an extremely powerful and verified calculation tool for the case of a material with any type of structure and geometry. In order to minimize errors, the paper proposes the method of least squares, a mathematical method that provides the best estimate for the set of values obtained by calculating FEM. It is useful to consider as many load cases as possible to obtain the best estimates. The elastic constants for a transversely isotropic material (composite reinforced with cylindrical fibers) are thus determined for a real case.

Purpose: To evaluate interfacial gap and fracture resistance of endodontically treated maxillary premolars, restored with different glass-fiber reinforced materials. Materials and Methods: Eighty-four extracted intact premolars were endodontically treated and MOD cavities prepared. Specimens were divided into 7 groups (n = 12 for each) as follows: sound teeth (G1); no restoration (G2); direct composite restoration with fiber-reinforced composite (everX Posterior GC) (G3); direct composite restoration (Filtek Supreme XTE, 3M Oral Care; "FSXTE") (G4); a horizontal layer of high-viscosity flowable composite (G-ænial Flow, GC) was placed on the pulp chamber floor, 10 mm x 3 mm glass fibers (everStick NET, GC) were inserted into the cavity (G5); same procedure as in group 5 except the direct restoration was made incrementally with FSXTE (3M Oral Care) (G6); composite overlays were placed (G7). Specimens were scanned with micro-CT to evaluate 3D interfacial gaps before and after chewing simulation using Mimics software to calculate voids between restoration and tooth (dentin and enamel). These data (in mm³) were collected for statistical analysis. Thereafter, specimens were loaded to fracture using a universal testing machine. Maximum breaking loads were recorded in Newton (N). The data obtained were analyzed using two-way ANOVA and post-hoc Tukey's test (p < 0.05). Results: ANOVA showed that horizontal glass-fiber insertions statistically significantly reduced interfacial gaps after chewing simulation. No differences in fracture resistance were found between Filtek Supreme XTE and everX Posterior; moreover, glass-fiber insertion did not significantly improve fracture resistance in either case. Composite overlays achieved significantly better fracture toughness than did direct restorations. Conclusions: For the direct restoration of endodontically treated premolars, the insertion of glass fibers into direct composite restorations was unable to guarantee a significant increase in the fracture resistance or a significant change in the fracture pattern. However, it significantly reduced interfacial gap volume after cycling fatigue. [ABSTRACT FROM AUTHOR]

Abstract A variety of fiber-reinforced polymer (FRP) has been described in literature, with a considerable subset of studies focused on fiber surface treatment (sizing), performance enhancement of matrix and fibers both synthetic and natural, and development of more ecologically sustainable composites. The present review discusses the different types of fibers and matrices and their applications, depending on the chemical and mechanical properties of their composites. In order to evaluate the performance of FRP composites and explore the characteristics of the involved materials, some analytical techniques are considered paramount, such as thermal analysis, microscopy, Fourier transform-infrared spectroscopy (FT-IR), and others. On this basis, this review addresses the state-of-the-art of material characterization methodologies, provides a comprehensive overview of different types of FRP found in literature, as well as links the analytical techniques with the main applications contributing to future studies and research in this area.

Prebiotics are non-digestible food ingredients that promote the growth of probiotic microorganisms in the intestines. They are marketed as feed supplements to support equine digestion, metabolism, growth, and immunity. Synbiotics are supplements that contain combinations of prebiotics and probiotic bacteria and/or yeasts. Both prebiotics and synbiotics are commercially available and are promoted for use in supporting equine digestion, enhancing athletic performance, as well as reducing stress and morbidity associated with intestinal disease. This narrative review aimed to summarize the literature on the use of prebiotics and synbiotic supplementation in equine nutritional practice. Sixteen papers were identified that reported on the use of prebiotic or synbiotic supplementation in horses. The literature presented here suggests that prebiotics may play a role in equine health and disease prevention. Prebiotics have been studied for their effects on athletic performance; increasing production of volatile fatty acids (VFA's) associated with hindgut fibre fermentation; insulin resistance and carbohydrate metabolism associated with reduction in the development of gastric mucositis, and hindgut acidosis and laminitis. Prebiotic compounds are thought to have an entero-protective effect by improving the composition and diversity of the intestinal microbiota, that in turn impacts immune function via metabolomic effects. Prebiotics derived from yeasts, including mannan-oligosaccharides (MOS), have been shown to reduce colonies of intestinal pathobionts and accelerate healing in acute enterocolitis. Overall, the current evidence to support the use of prebiotics and synbiotics in equine health and disease is not extensive but promising.

Utilizing agricultural waste and natural fibers minimizes environmental impact and can improve the acoustic and thermal conditions of buildings. Natural fibers can be an alternative to non-biodegradable synthetic sound-absorbing materials. This study aimed to investigate the acoustic and thermal properties of insulating materials made from wool and sugarcane bagasse. Thermal conductivity, thermal resistance, acoustic and moisture absorption, and fire properties of five insulating materials made from sheep wool, goat fiber, camel wool as well as pith and fiber bundles of sugarcane bagasse were determined. The measurement of the sound absorption coefficient was performed in an impedance tube. The thermal resistance and thermal conductivity coefficient were measured according to the ASTM D5334–08 Standard. The findings show that camel wool has the highest sound-absorbing performance, thermal insulation, and fire-resistant properties. The lowest value of the noise reduction coefficient (NRC) was 0.52 for goat fiber, and the highest was 0.74 for camel wool. The maximum sound absorption coefficient of camel wool was 0.95 at a frequency above 1000 Hz. Thermal conductivity varies between 0.038 and 0.046W/(M.K). Hence, all materials tested can be considered thermally insulating. The results showed insulating materials made from wool, especially camel wool, had better performance than fiber and pith of sugarcane bagasse.

It is known that concrete with high ductility reduces fatalities because it absorbs more energy during an earthquake. The aim of this study is to increase the ductility of concrete by using glass fiber mesh (GFM) left over from the use of plaster in structures and to support sustainability by reusing waste materials in concrete. Another aim is to contribute to the economy by using waste fibers instead of expensive fibers such as carbon and polypropylene in concrete. Two types of concrete were used: class C25 concrete and self-compacting concrete. The specified number of GFM materials was cut into 3 cm wide pieces and placed in 10 cm × 10 cm × 50 cm concrete beam specimens in varying numbers. It was found that the flexural values of the obtained specimens gave slightly better results than the prepared reference specimen. In addition, the increasing stress zones in the beams were visualized using the ANSYS software.

Engineered cementitious composites (ECC) exhibits impressive tensile strength but has significant environmental drawbacks due to high cement consumption. Recently, engineered geopolymer composites (EGC) have gained attention as a potential ECC alternative. This comprehensive study reviews the latest EGC advancements, encompassing mix design, design theory, engineering properties, environmental benefits, and durability. It emphasizes how factors like activators, precursors, fibers, additives, and aggregates impact EGC properties, making it a cost-effective material for fire, chemical resistance, and dynamic loads. To address limitations in traditional literature reviews, innovative research methods, including scientometric analysis, were employed to provide a cohesive analysis. This review aims to facilitate knowledge dissemination and collaboration by summarizing EGC advances and highlighting remaining challenges in developing practical applications. It is revealed from the review that various manufacturing methods enhance geopolymers, especially in geopolymer concrete, where replacing 50% of ordinary Portland cement with fly ash boosts strength. Geopolymer concrete excels in pre-cast applications, offering durability and resistance to harsh conditions as an eco-friendly alternative to Portland cement. It suits highway pavement, walls, marine coatings, and tiles, reducing carbon emissions and promoting efficient waste management. EGCs find broad use in construction due to their strong, durable, and eco-friendly qualities, supporting sustainable infrastructure development.

Recently, studies on sustainability and ecology have become widespread in almost all sectors. One of the most important reasons for this spread is the rapid increase in industrialization and, thus, the increase in waste caused by industries. In this context, significant efforts are being made to evaluate some of these wastes. One of these efforts is the production of geopolymers. In this research, metakaolin and slag-based geopolymer mortar samples were manufactured, and polyvinyl Alcohol, basalt, and macro synthetic polypropylene fibers were used to enhance the physical, mechanical, and high-temperature resistance of the sample. Physical and mechanical tests of the produced samples were performed after 28 days. Then, elevated-temperature experiments were conducted to evaluate the behavior of the fibers under the influence of high temperature. Following the high-temperature test, physical, mechanical and microstructure tests of the samples were performed. As a result, basalt fiber enhanced the compressive strength of 800 °C-exposed samples by 7.72% compared to the fiber-free sample. Also, polyvinyl Alcohol fiber increased the energy absorption capacity of the samples by increasing Charpy impact values to 72.22% compared to fiber-free sample. Moreover, macro synthetic polypropylene fiber reduced capillary water absorption value up to 12.44% compared to fiber-free sample.

Fibrous structures are promising candidates for oil–water separation applications. In this study, we have produced poly(styrene-b-isobutylene-b-styrene) thermoplastic elastomeric fibers with the centrifugal spinning fiber production method. The optimal fiber production conditions were achieved when using a 25% w/w solution concentration in an 80/20 tetrahydrofuran/toluene (w/w) solvent system at 8000 rpm rotational speed. The produced fibers were bead-free and smooth-surfaced with a diameter of 3.68 µm. The produced fibers were highly hydrophobic and oleophilic, suggested by a water contact angle of 129° and the instantaneous absorption of the oil droplet. The oil absorption study showed fast absorption kinetics with 94% relative oil uptake after 1 min and a maximum of 16.5 g sunflower oil/g fiber. The results suggest that polyisobutylene-based thermoplastic elastomers could be promising alternatives in oil absorption applications. [ABSTRACT FROM AUTHOR]

Self-oscillating coupled machines are capable of absorbing energy from the external environment to maintain their own motion and have the advantages of autonomy and portability, which also contribute to the exploration of the field of synchronization and clustering. Based on a thermally responsive liquid crystal elastomer (LCE) spring self-oscillator in a linear temperature field, this paper constructs a coupling and synchronization model of two self-oscillators connected by springs. Based on the existing dynamic LCE model, this paper theoretically reveals the self-oscillation mechanism and synchronization mechanism of two self-oscillators. The results show that adjusting the initial conditions and system parameters causes the coupled system to exhibit two synchronization modes: in-phase mode and anti-phase mode. The work conducted by the driving force compensates for the damping dissipation of the system, thus maintaining self-oscillation. The phase diagrams of different system parameters are drawn to illuminate the self-oscillation and synchronization mechanism. For weak interaction, changing the initial conditions may obtain the modes of in-phase and anti-phase. Under conditions of strong interactions, the system consistently exhibits an in-phase mode. Furthermore, an investigation is conducted on the influence of system parameters, such as the LCE elastic coefficient and spring elastic coefficient, on the amplitudes and frequencies of the two synchronization modes. This study aims to enhance the understanding of self-oscillator synchronization and its potential applications in areas such as energy harvesting, power generation, detection, soft robotics, medical devices and micro/nanodevices. [ABSTRACT FROM AUTHOR]

Unlike the culm hollow structure of most bamboo species, Oxytenanthera abyssinica has a unique solid or semi-solid culm, which may endow it with superior mechanical performance. In this study, the variation in fiber morphology and micro-mechanical properties across the radial regions of bamboo culm was examined by optical microscopy, scanning electron microscopy, X-ray diffraction, and nanoindentation. Results showed that the mean values of vascular bundle frequency and fiber tissue proportion were 1.76 pcs/mm 2 and 21.04%, respectively, both of which increased gradually from inner to outer. The mean length, diameter, and length-diameter ratio of the fiber were 2.10 mm, 21.54 μ m, and 101.41 respectively. The mean indentation modulus of elasticity (IMOE) and hardness were 21.34 GPa and 545.88 MPa. The IMOE exhibited a significant increase from the inner to the middle region, and little change was observed from the middle to the outer region. There were slight fluctuations in hardness along the radial direction. The mean crystallinity and microfibril angle(MFA) of the fibers was 68.12% and 11.26 degrees, respectively. There is a positive correlation between cellulose crystallinity and the IMOE and hardness, while there is a negative correlation between the MFA and the IMOE and the hardness. [ABSTRACT FROM AUTHOR]

Gestational diabetes mellitus (GDM), defined as abnormal glucose tolerance that presents during the second and third trimesters of pregnancy, is a growing issue in the United States and worldwide. If left untreated or poorly controlled, GDM can result in numerous consequences for both the mother and the fetus; thus, it is imperative that different avenues of management for GDM be explored. There is a paucity of studies that examine how lifestyle changes, including dietary and physical activity, affect management of GDM. We examined how counseling on lifestyle changes can affect cardiometabolic risks in women with GDM. We conducted a 12-week randomized controlled trial based on behavioral counseling in which women with GDM (N = 38) were randomized into either a nutrition education (control) (N = 18) group or nutrition intervention (N = 20) group. The nutrition education group were given dietary counseling regarding healthy dietary choices based on USDA guidelines, while the nutrition intervention group were instructed to consume a total of one cup of whole berries and one cup of leafy vegetables daily along with performing postprandial exercise (walking). Blood samples, anthropometric measures, and dietary and physical activity data, recorded in daily food and activity logs, were collected at baseline and at the end of the study and compared between the two groups. Dietary counseling on supplementation with whole berries and leafy vegetables resulted in increased fiber intake, increased antioxidant intake and total serum antioxidant capacity, improved random blood glucose, decreased serum IL-6, and improved HDL cholesterol versus the control group (all p < 0.05). These results highlight that whole berry and leafy vegetable supplementation-based dietary counseling can improve the metabolic pathways involved in gestational diabetes pathogenesis and prognosis. These functional foods must be recommended in the management of pregnancies affected by GDM. [ABSTRACT FROM AUTHOR]

The epoxy composites with ramie fiber and rice husk ash functional additives were prepared and characterized in this study. This investigation aims to find out the suitable silicon additive among Si3N4 and Si2N2O to improve the flammability, wear and thermal stability of ramie-epoxy composite. The additives were prepared from waste rice husk ash via thermo-chemical process. The composites were manufactured by hand layup process and characterized in accordance with respective ASTM standards. The results of this study demonstrates that only composite designation RRS22 has a lower combustion rate than the pure epoxy at about 5.66 mm/min, which is constructed of 40 vol% ramie fiber and 3.0 vol% Si3N4particles. As well as flammability test on different composites shows compared to Si2N2O particle composites, Si3N4particle composites have the slowest rate of propagation. The mass loss, COF, and sp. wear rate for the composite designation RRS22 are similarly decreased up to 0.061 g, 0.28, and 0.005 mm3/Nm when Si3N4particles are added at a rate of 3.0 vol%. Also, the additional incorporation of Si3N4particles raises the decomposing temperature for composites with the designations RRS2 and RRS22 with inclusion of Si3N4 particles by 1.0 and 3.0 vol%. Natural fiber composites with such great wear resistance and thermal stability could be used in industrial applications, aerospace structures and in automotive sectors. [ABSTRACT FROM AUTHOR]

Determining the optimal requirements from dietary fiber and fat for Egyptian geese is a matter of great concern regarding health, production and growth. Therefore, the current study estimated the effects of different dietary fiber and fat levels on functions of liver and kidney, lipid profile, immunity and antioxidant measurements of the growing Egyptian geese. 150 Egyptian goslings (4 weeks old), with almost the same body weights were randomly allocated into 6 groups (25 goslings/group). All groups were subdivided into five replicates, each replicate contains five geese. Liver and kidney functions, immunity and antioxidant parameters were not significantly affected the different studied levels of fiber and fat or by their interaction. Various levels of fiber significantly affected total cholesterol, triglycerides, LDL-cholesterol and VLDL-cholesterol in a concentration-dependent manner and the lowest the lipid profile values were obtained at 12%. In conclusion, the present findings show that use of dietary fiber up to 12% and 5% dietary fat showed no detrimental effects on the immune status and general health of geese and resulted in the preferable lipid profile. This experiment provides a base for further study about the optimal requirements from dietary fiber and fat for the growing Egyptian geese. [ABSTRACT FROM AUTHOR]

Neutral detergent fiber (NDF) is the most commonly reported metric for fiber in dairy cattle nutrition. An empirical method, NDF is defined by the procedure used to measure it. The current definitive method for NDF treated with amylase (aNDF) is AOAC Official Method 2002.04 performed on dried samples ground through the 1-mm screen of a cutting mill with refluxing and then filtration through Gooch crucibles without (AOAC−; reference method) or with (AOAC+) a glass fiber filter filtration aid. Other methods in use include grinding materials through the 1-mm screen of an abrasion mill, using filtration through a Buchner funnel with a glass fiber filter (Buch), and use of the ANKOM system (ANKOM Technology, Macedon, NY) that simultaneously extracts and filters samples through filter bags with larger (F57) or smaller (F58) particle size retentions. Our objective was to compare the AOAC and alternative methods using samples ground through the 1-mm screens of cutting or abrasion mills. Materials analyzed were 2 alfalfa silages, 2 corn silages, dry ground and high-moisture corn grains, mixed grass hay, ryegrass silage, soybean hulls, calf starter, and sugar beet pulp. Samples were run in duplicate in replicate analytical runs performed on different days by experienced technicians. Compared with cutting mill–ground samples, the aNDF% of dry matter results from abrasion mill–ground samples were or tended to be lower for 8 of 11 samples. Method affected aNDF% results for all materials, with method × grind interactions for 6 of 11 samples. For ash-free aNDF% assessed with cutting mill–ground materials, a priori selected contrasts showed that the number of materials for which methods differed or tended to differ from the AOAC methods were 4 (Buch), 8 (F57), and 3 (F58); and 3 for AOAC– versus AOAC+. However, statistically different does not necessarily mean substantially different. For a given feed and grind, a positive value for the absolute difference between the AOAC– mean and an alternative method mean minus 2 times the standard deviation of AOAC− suggests that values for the alternative method fall outside of the range of results likely to be observed for the reference method. The number of observed positive values for materials processed with cutting and abrasion mills, respectively, were 0 and 2 (AOAC+); 2 and 2 (Buch); 8 and 10 (F57); 4 and 7 (F58); and 0 and 4 (AOAC−). With the materials tested, methods in order of agreement with the reference method were Buch, F58, and F57, which often gave lower values. The AOAC+ gave results similar to AOAC−, substantiating it as an allowed modification of AOAC−. Best agreement between the reference method and variant NDF methods was achieved with the 1-mm screen cutting mill grind. The 1-mm abrasion mill grind produced more aNDF% results that were lower than the reference method but with fewer differences when filter particle retention size was smaller. The use of filters that retain finer particles could be explored to improve comparability of variant NDF methods and grinds. Further evaluation with an expanded set of materials is warranted. [ABSTRACT FROM AUTHOR]

In this study, 10 mg fluconazole (10 FCZ) and 10 mg gentamicin (10 GEN) loaded with 40% polymethylmethacrylate (40% PMMA) fibers were fabricated by electrospinning and the performance of the formulations (40% PMMA, 40% PMMA/10 FCZ, 40% PMMA/10 GEN, and 40% PMMA/10 FCZ/10 GEN) was tested. 10 mg Gentamicin-loaded 40% PMMA fiber mat showed a more significant zone of inhibition against the S. aureus compared to the zone of 40% PMMA/10 GEN/10 FCZ fiber. The biocompatibility test using a human adipose-derived mesenchymal stem cell (MSCs) as a cell model proved that the amount of loaded and released GEN has no toxic effects on the MSCs. [ABSTRACT FROM AUTHOR]

Cyanobiphenyl homologues are important liquid crystals to use in some applications since they exhibit intrinsic properties in a certain temperature interval including room temperature. Recently, generating composites with polymers and liquid crystals by electrospinning has drawn great interest. Here, cyanobiphenyl homologues of chain carbon numbers 5–8 and polyacrylonitrile were spun using single-needle electrospinning for the first time. Morphological, optical, aligning, and thermal properties of spun fibers investigated. The thinnest and thickest fibers were obtained in fibers involving cyanobiphenyl of chain carbon number 5 and 6, respectively considering the scanning electron microscopy images. Also, it was proved that all the cyanobiphenyl members were self-aligned throughout the fibers as a core using polarized optical microscopy. The existence of the cyanobiphenyl homologues in the structure of the fibers was presented by infrared spectroscopy results. In addition, the mass variation depending on temperature and calorimetric measurements were studied. Phase transition temperatures of the bulk cyanobiphenyls and the fibers were compared. The results showed that cyanobiphenyl homologues of chain carbon numbers 5–8 and polyacrylonitrile were able to be spun successfully and the fibers had the potential to be used in applications because the physical properties of the fibers were attractive. [ABSTRACT FROM AUTHOR]

Hemp is cultivated for its high content in natural, durable, resistant fibres and for its oil-rich seeds. Hemp for seeds is cultivated to fulfil the requests in the technical, cosmetic, food, fodder fields. Hemp has the highest industrialization capacity of all technical plants. Because for a long period of time, the cultivation of hemp in Europe as well as in Romania was in decline, being continuously practiced only in certain European states, it is desired to emphasize how hemp can make an essential contribution to the development of innovative solutions regarding the relaunch of the industrial hemp sector. The paper presents some research results obtained during the realization and experimentation of some technical equipment intended for the mechanization of the works within the hemp cultivation technologies in different systems. The technology of establishing, managing and valorising the hemp culture for fibre or seed can have perspectives starting with the conventional system, the ecological or successive one and at the level of experimental lots. [ABSTRACT FROM AUTHOR]

Numerous studies have been conducted on fiber-reinforced concrete; however, comparative investigations specifically focusing on the utilization of fibers in CLSM remain limited. In this study, we conducted a systematic investigation into the mechanical properties of controlled low-strength material (CLSM) by manipulating the length and doping amount of fibers as control variables. The 7-day compressive strength (7d-UCS), 28-day compressive strength (28d-UCS), and 28-day splitting strength of CLSM were employed as indicators to evaluate the material's performance. Based on our comprehensive analysis, the following conclusions were drawn: (1) A positive correlation was observed between fiber length and material strength within the range of 0–6 mm, while conversely, a negative correlation was evident. Similarly, when the fiber doping was within the range of 0–0.3%, a positive correlation was identified between material strength and fiber doping. However, the strength of CLSM decreased when fiber doping exceeded 0.3%. (2) SEM and PCAS analyses provided further confirmation that the incorporation of fibers effectively reduced the porosity of the material by filling internal pores and interacting with hydration products, thereby forming a mesh structure. Overall, this study offers valuable insights into the manipulation of fiber length and doping amount to optimize the mechanical properties of CLSM. The findings have important implications for the practical application of CLSM, particularly in terms of enhancing its strength through fiber incorporation. [ABSTRACT FROM AUTHOR]

Hemp is usually divided into “drug hemp” and “industrial hemp”. Industrial hemp contains less than 0. 3% tetrahydrocannabinol（THC） and is mainly used in the textile sector. Hemp is a kind of natural bast fiber, whose fineness is similar to that of cotton fibers. It is a kind of fine fiber among common fibers. Hemp fabrics have a slender middle cavity inside, and many holes and gaps are distributed longitudinately, making hemp fabrics soft and comfortable to wear. Hemp fibers consist of cellulose and other non-cellulose colloids such as hemicellulose, lignin, pectin and wax, which must be removed by degumming to meet textile standards. Compared with other hemp, lignin content in hemp fibers is higher, and lignin has higher stability to acid, alkali, hydrogen peroxide and other oxidants, which increases the difficulty of degumming hemp. The existing degumming techniques mainly include biological, physical and chemical methods. The biological degumming process is simple and easy to operate, and environmental friendly, with low energy consumption; the effect on fibers is mild and does not cause excessive damage. But in the actual production, the strains that can produce specific enzymes are few, the enzyme activity and enzyme yield are low, and the production cost is high; the degumming process is difficult to control, degumming effect is not ideal, and the product quality is unstable, so in industrial production, it is necessary to be combined with other degumming methods to meet the quality requirements. Physical degumming is the use of mechanical force to separate and remove part of the gum on the fiber, including the mechanical method, the ultrasonic method, the steam explosion method and the low temperature plasma method. This kind of method is simple to operate and does not pollute the environment, but the degumming effect is poor, so it is often used as an auxiliary degumming means in actual production. A breakthrough has been made in the research on the chemical degumming method of hemp fibers. Researchers have simplified the degumming process of hemp fibers, improved the chemical degumming effect of hemp fibers to a certain extent, and reduced the pollution of degumming wastewater to the environment. But these new chemical degumming methods are not perfect, there are such problems as high cost, high energy consumption, difficult-to-control degumming process parameters and unstable product quality, so there is still a long way to go before their being put into practical industrial production on a large scale. On this basis, the paper summarizes three basic methods of degumming hemp: biological degumming mainly includes the traditional degumming by water and rain, and the modern biological degumming technology by extracting crude enzyme liquid and compounding enzyme. In addition to the mechanical method, ultrasonic method and steam blasting method, such physical degumming methods as the plasma oxidation and supercritical CO2 method used in recent years are also mentioned. Chemical degumming is mainly summarized in three aspects: new oxidation degumming, organic solvent degumming and using physical methods to enhance the effect of chemical degumming. Moreover, the green degumming process with low energy consumption and high efficiency is reviewed. By combining with the research results in recent years, it is found that the three degumming means have their own advantages, but they also have their own problems. Therefore, according to the characteristics of each degumming method, the combination of different degumming technology can often get better degumming effect. In future production, a variety of degumming means will be combined, and the physical degumming method will be used as pre-treatment in the early stage, and supplemented by enzyme or microbial further degumming to reduce environmental pollution. On the basis of the first two, the chemical method is appropriately used to completely remove gum in order to improve the product quality. [ABSTRACT FROM AUTHOR]

Plastic films have been widely adopted to improve plant growth in agriculture, covering soil temperature, evaporation reduction, and water conservation in the soil. The most extensively-used materials are polyethylenes (PEs) for agricultural mulching applications, due to their excellent tensile strength and resistance to degradation, such as the low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and copolymer poly (ethylene-vinyl acetate) (EVA). However, conventional film is made of polyethylene, leading to serious "White Pollution". Therefore, degradable materials can be expected to improve the polluted environment. Among them, crop straw can serve as the biggest renewable material with a variety of sources on the earth. Particularly, film mulching can be one of the most important approaches for the growth of crops. Normally, the degradable mulch film is commonly composed of biobased materials that rely on the biodegradable effects of sunlight (ultraviolet rays) and soil microorganisms. Furthermore, the biodegradable mulch film can be decomposed into carbon dioxide, water, and minerals, indicating a friendly environment. Moreover, the degradation rate of biodegradable films is influenced by the chemical components of the polymers. Crop straw can be obtained from corn, rice, wheat, sorghum, soybean, or sugar cane, indicating an abundant source of biomaterials. For instance, 700 million tons of various types of crop straw have been generated each year in China. Many attempts have been made to manufacture wood-based composites with agricultural residues, such as straw. Crop straw is an abundant agricultural residue with higher ash content, leading to the potential additional application as fodder. This study aims to improve the comprehensive utilization rate of crop straw. The straw film was made of rice straw by the in-situ polymerization, and tested as the ridge mulch for the crops. The results demonstrate that the mechanical properties of the straw fiber film were significantly enhanced by the modification. XRD results show that the crystallinity index of the modified film increased to 64.42% (raw film=38.11%). The enhancement in the crystallinity of the straw fiber film can be attributed to the functional additives, which penetrated into the amorphous region of cellulose. Microfibriles were obtained in the amorphous region, particularly close to the crystalline region, resulting in an increase in the width of the crystalline region of cell wall cellulose microfibril. The contact angle of the modified mulching film increased from 95.35° to 118.43°. Thermogravimetric (TG) analysis results indicated that the thermal stability of the modified film was improved after treatment. Moreover, the different chemical bonds in the unmodified and modified films revealed the chemical cross-linking between the film fibers and modifier after FTIR analysis. XPS analysis showed that there was an increase in the atomic concentration ratio of oxygen and carbon in the straw fiber base membrane after modification, indicating that the chemical cross-linking reaction between the modifier and the mulch fiber resulted in the increase of oxygen-containing functional groups. SEM-EDXA indicated that the modifier was uniformly dispersed in the fiber film, indicating an improvement in the mechanical properties. The experiment of tobacco mulch showed that the straw fiber base membrane improved the overall level of tobacco planting. Overall, the superior properties of the modified straw fiber film can make great potential for agricultural application. [ABSTRACT FROM AUTHOR]

A centrifugal pump whose open impeller was made of polycarbonate was adopted to explore the influence of different concentrations of slender fiber particles on the external characteristics of the pump and to obtain the motional characteristics of the particles in the channels of the impeller. The external characteristics of the pump were used to determine the performance of the pump. A high-speed photographic system was used to analyze the motion of fiber particles in the channels of the impeller. Changes in the head and efficiency of the pump and changes in the distribution of fiber particles in impeller channels were obtained under different concentrations of fiber particles and different flow rates of fiber suspensions. The head associated with the transport of a fiber suspension whose mass concentration of fiber particles was 0.15% and the head associated with the transport of a fiber suspension whose mass concentration of fiber particles was 0.30% did not differ greatly from the head associated with the transport of clean water. However, compared to the transport of clean water, the transport of the fiber suspensions improved the efficiency of the pump. When the pump transported the fiber suspension whose mass concentration of fiber particles was 0.30%, on average, the efficiency of the pump increased by 8.49%. When the flow rates of the fiber suspensions increased, the uniformity of the distribution of the particles increased. When entering the impeller, a small number of fiber particles showed rotating and flapping motions. However, the motions gradually disappeared as the particles left the impeller. At a constant radius (i.e., 75% and 95% radius, respectively), the velocity profile increased gradually when the mass concentration of fiber particles increased from 0.1% to 0.15%. It is manifest that fiber suspension undergoes less flow loss as the mass concentration of fiber particles increases. [ABSTRACT FROM AUTHOR]

This research aims to develop durable repair materials that can resist shrinkage cracking by exploring the role of creep in reducing shrinkage stress. In this regard, the creep effect can only be quantified if an accurate creep prediction model and theoretical analysis of the shrinkage stress in the patch repair system exist. For this purpose, the research was carried out in the following sequences: first, the research investigated the short-term creep of the patch repair materials containing accelerator and micro-synthetic fibers in the 0.00-0.12% volume fraction range. This short-term creep was measured on five-cylinder specimens (having a diameter of 75 mm and a height of 275 mm). Three specimens were used to determine the deformation of the repair material under unloading conditions, while those remaining were used to determine the total deformation under loading conditions. The amount of creep deformation was determined by taking away the unloaded (shrinkage) and instantaneous (elastic) deformations from the total deformation of the loaded specimens. Secondly, a modified prediction model of ACI 209R-08 is introduced to accurately capture the rate and magnitude of the observed creep of the repair materials. Finally, a formulated theoretical analysis of shrinkage stress in the patch repair system was proposed to examine how creep potentially reduces the repair material's cracking tendency. The results show that the asymptotic value of the creep curve is attained at an earlier age and that its magnitude is greater than that of most concrete. The modified ACI 209R-08 prediction model can closely estimate the repair materials' creep behavior. The best-fit line, residual values, and coefficient of error analyses confirm the modified model's prediction accuracy. The analysis of tensile stress development in the repair layer suggests that creep can reduce stress by up to 50%. With such a reduction, the repair material is expected to be durable in resisting shrinkage and cracking tendency. [ABSTRACT FROM AUTHOR]

This study proposes a novel quartz crystal microbalance-based sensor using polyvinyl acetate nanofibers overlaid with maltodextrin to enhance sensitivity toward trimethylamine (TMA) gas. The sensor demonstrated a remarkable increase in sensitivity by 8.3 times, with a detection limit of 15.6 ppm. The enhanced sensitivity is due to reversible intermolecular Lewis acid–base interaction between active groups of maltodextrin and TMA gas molecules. Moreover, the sensor exhibited good selectivity, stability, and fast response and recovery times of 141 s and 116 s, respectively. The proposed sensor offers a promising alternative to conventional methods for accurately monitoring TMA gas levels in the air. [ABSTRACT FROM AUTHOR]

The objective of this research is the development of a magnetic sheath-core bicomponent fiber. Therefor technical oxide is mixed in polypropylene using compounding. The compound (sheath) and pure polypropylene (core) are further processed in melt spinning into a magnetic bicomponent fiber with textile strength of 26.36 ± 1.62 cN/tex. Bicomponent fiber yarns can be inductively heated above 175°C in less than 10 s. These fibers could be used for thermal bonding of fiber-reinforced plastics, joining techniques of high efficiency due to their possibility to form a material-bonded connection and fiber orientation in nonwovens through a directional magnetic field. [ABSTRACT FROM AUTHOR]

In this paper, a microwave phase compensation scheme is adopted. It utilizes microwave signals of different frequencies for round-trip signal transmission over a 250 km fiber optic link to mitigate the impact of parasitic reflections. Additionally, dispersion compensation fibers are employed to compensate for the dispersion in the fiber optic link. Bidirectional optical amplifiers are utilized to compensate for the losses in long-distance fiber optic links and reduce optical path asymmetry. By implementing these methods, the transmission stability of the fiber optic microwave frequency transmission system achieves 5.6 × 10−15 at 1 s and 2.8 × 10−18 at 100,000 s. [ABSTRACT FROM AUTHOR]

The polarization properties of bismuth active centers (BACs) are important for many applications of bismuth-doped fibers, but they are still lacking in study. In this paper, we present the measurements of polarized luminescence (PL) of the BACs formed in a Bi-doped phosphosilicate glass matrix. This research was performed on phosphosilicate fiber preforms used for the drawing of active bismuth-doped fibers for efficient optical amplifiers and lasers. The degree of polarization (DOP) of luminescence of the BACs associated with phosphorus and silica (BAC-P and BAC-Si) is provided and discussed. The DOP of luminescence at the 1320 nm wavelength appeared to be around 19%, 0% and 7.5% for pumps at 1240 nm, 762 nm and 425 nm, respectively. The DOP of PL caused by resonant excitation may be described in terms of a model of a partially anisotropic oscillator with the parameters represented by the principal axes of an ellipsoid. For the resonant excitation at 1240 nm, the ratio of the major principal axis to the minor one turned out to be 5.1 and 3.0 for BAC-P and BAC-Si, respectively. [ABSTRACT FROM AUTHOR]

Different research studies have identified specific groups or certain dietary compounds as the onset and progression of obesity and suggested that gut microbiota is a mediator between these compounds and the inflammation associated with pathology. In this study, the objective was to evaluate the dietary intake of 108 overweight (OW), obese (OB), and normal-weight (NW) individuals and to analyze their gut microbiota profile to determine changes and associations with Body Mass Index (BMI) and diet. When individuals were compared by BMI, significant differences in fiber and monounsaturated fatty acids (MUFAs) intake were observed, showing higher adequacy for the NW group. The analysis of gut microbiota showed statistical differences for 18 ASVs; Anaerostipes and Faecalibacterium decreased in the OW/OB group, whereas the genus Oscillospira increased; the genus was also found in the LEFSe analysis as a biomarker for OW/OB. Roseburia faecis was found in a significantly higher proportion of NW individuals and identified as a biomarker for the NW group. Correlation analysis showed that adequation to nutritional recommendation for fiber indicated a higher abundance of Prevotella copri, linearly correlated with F. prausnitzii, Bacteroides caccae, and R. faecis. The same correlation was found for the adequation for MUFAs, with these bacteria being more abundant when the intake was adjusted to or below the recommendations. [ABSTRACT FROM AUTHOR]

To respond to high-speed characteristics and complicated airflow of the air-extraction rotor, the paper takes advantage of ANSYS parametric design language to develop the parametric finite element modeling program by taking the geometric feature of the slip plane as the design variable, so as to propose a mathematical model applicable to dynamics optimization of the rotor. The optimal design parameters of the slip plane are obtained through dynamics optimization (α ≈ 13.92°, L ≈ 11.17 mm), and the centrifugal stress and static deformation of the rotor body are further reduced while increasing its fundamental frequency by about 7.15%, so that it can adapt to higher safety critical speed. The RNG k - ε turbulence physics model is applied to the numerical simulation of the airflow field in the optimal spinning channel, and a computational domain of single-phase steady fluid with nonstructural mesh is constructed by using ICEM CFD and FLUENT software. On this basis, the simulation result with excellent convergence of the flow field is obtained through the SIMPLE algorithm and pressure-velocity coupled solution. In addition, by virtue of the two-dimensional and three-dimensional flow field characteristic analysis for key fields (like the rotor wall, fiber pipeline, false twister, collecting groove, inlet and outlet), the airflow field state in the spinning channel (like the static pressure, dynamic pressure, velocity vector field, turbulence intensity and streamline trajectory) is confirmed, which will be conducive to gain a deep insight into the open-end spinning mechanism of the air-extraction rotor. [ABSTRACT FROM AUTHOR]

The freeze-thaw damage mechanism of concrete was summarized, and the influence and modification mechanisms of mineral admixtures, chemical admixtures, aggregate types and fibers on the freezeresistance performances of self-compacting concrete (SCC) were reviewed. Mineral admixtures and chemical admixtures reduce the porosity and microporous spacing of hardened SCC by changing the workability and air content of its mixture. The porosity, mechanical properties, deformation properties and particle composition of coarse and fine aggregates affect the fluidity of mixes and the state of water residence in the system, changing the pore structure and pore connectivity of hardened SCC. The fibers retard the generation and expansion of cracks caused by capillary pressure during freezing and thawing through micro-air-entraining and bridging and crack-blocking effects. The problems and development prospects in the research and application of SCC were further elaborated, and the ways to improve the frost resistance of self-compacting concrete were proposed. [ABSTRACT FROM AUTHOR]

Fibrous concrete has good properties such as high ductility, high strength, suitable energy absorption and cracking resistance, which can be useful in many applications. This type of concrete is one of the best materials used in the construction of impact-resistant masonries, such as burial masonry structures, and explosive masonry warehouses. In this study, an artificial intelligence assessment based on the experimental test data from a laboratory has been performed on the fibrous concrete to evaluate the behavior of the samples at elevated temperatures and determine the most governing parameter on the mechanical properties of the fibrous concrete at elevated temperatures. For the first time, a hybrid intelligence algorithm has been developed based on the neural network structure using both genetic and swarm optimization algorithms. The ANFIS-PSO-GA (APG) algorithm was trained with experimental data and evaluated the flexural load and deflection of the samples. In order to detect the most prominent feature in the fire resistance of the fibrous concrete, five different subdatasets were designed. The results of the APG algorithm have been challenged with the ANFIS-PSO algorithm, which is a well-known hybrid numerical evaluation algorithm. As per the results, the newly designed APG algorithm has been successfully performed on both deflection and flexural prediction phases. Based on the numerical achievements, fiber features such as the fiber content and fiber mechanical properties are governing factors on the fibrous concrete resistance at elevated temperatures. [ABSTRACT FROM AUTHOR]

Based on the practical application of a new energy vehicle, this paper introduces the factors affecting the cleanliness of the body in white (BIW), and discusses the improvement direction of the cleanliness of the BIW from the sources of welding slag, iron scraps, grease, dust, fibers, control methods and pre-cleaning measures after coating process. Optimization of the BIW cleanliness is one of the important measures to prevent and control the defects of electrophoretic film, by which can ensure the stability of the quality of electrophoretic film. These measures might provide referential value for other vehicle coating processes. [ABSTRACT FROM AUTHOR]

Dairy farming requires forages with high neutral detergent fiber (NDF) to maximize milk production, sustain cows' health, and ensure the economic and environmental sustainability of the dairy farm. The objectives of this study were to determine the effects of the brown midrib (BMR) genotype, agronomic environment, and maturity at harvest on the NDF digestibility (NDFD) and the composition of the cell wall of corn plant tissues. In this plot study, one conventional and one BMR corn hybrid were planted and subjected to an abundant (60,000 seeds/ha and 225 kg N/ha) and a limited (90,000 seeds/ha and 180 kg N/ha) environment. The ruminal NDFD was determined in vitro in leaf blades, leaf sheaths, and stem internodes. Cell walls from BMR corn had greater NDFD than cell walls from conventional corn on most tissues. Relative to the abundant environment, the limited environment had minimal effects on NDFD. As maturity advanced, NDFD decreased for various but not all tissues. In conclusion, under the conditions of this study, intrinsic characteristics of corn, such as genotype and maturity at harvest, had a greater effect on NDFD than environment or agronomic management. [ABSTRACT FROM AUTHOR]

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One of the biggest challenges for a more widespread utilization of plant fibers is to better understand the different molecular factors underlying the variability in fineness and mechanical properties of both elementary and scutched fibers. Accordingly, we analyzed genome-wide transcription profiling from bast fiber bearing tissues of seven different flax varieties (4 spring, 2 winter fiber varieties and 1 winter linseed) and identified 1041 differentially expressed genes between varieties, of which 97 were related to cell wall metabolism. KEGG analysis highlighted a number of different enriched pathways. Subsequent statistical analysis using Partial Least-Squares Discriminant Analysis showed that 73% of the total variance was explained by the first 3 X-variates corresponding to 56 differentially expressed genes. Calculation of Pearson correlations identified 5 genes showing a strong correlation between expression and morphometric data. Two-dimensional gel proteomic analysis on the two varieties showing the most discriminant and significant differences in morphometrics revealed 1490 protein spots of which 108 showed significant differential abundance. Mass spectrometry analysis successfully identified 46 proteins representing 32 nonredundant proteins. Statistical clusterization based on the expression level of genes corresponding to the 32 proteins showed clear discrimination into three separate clusters, reflecting the variety type (spring-/winter-fiber/oil). Four of the 32 proteins were also highly correlated with morphometric features. Examination of predicted functions for the 9 (5 + 4) identified genes highlighted lipid metabolism and senescence process. Calculation of Pearson correlation coefficients between expression data and retted fiber mechanical measurements (strength and maximum force) identified 3 significantly correlated genes. The genes were predicted to be connected to cell wall dynamics, either directly (Expansin-like protein), or indirectly (NAD(P)-binding Rossmann-fold superfamily protein). Taken together, our results have allowed the identification of molecular actors potentially associated with the determination of both in-planta fiber morphometrics, as well as ex-planta fiber mechanical properties, both of which are key parameters for elementary fiber and scutched fiber quality in flax. [ABSTRACT FROM AUTHOR]

Summary: The kinetics of wood formation in angiosperms are largely unknown because their complex xylem anatomy precludes using the radial position of vessels and fibers to infer their time of differentiation.We analyzed xylogenesis in ring‐porous ash (Fraxinus angustifolia) and diffuse‐porous beech (Fagus sylvatica) over 1 yr and proposed a novel procedure to assess the period of vessel and fiber enlargement using a referential radial file (RRF).Our approach captured the dynamics of wood formation and provided a robust estimation of the kinetics of vessel and fiber enlargement. In beech, fibers and vessels had a similar duration of enlargement, decreasing from 14 to 5 d between April and July. In ash, wide vessels formed in April enlarged at a rate of 27 × 103 μm2 d−1, requiring half the time of contemporary fibers (6 vs 12 d), and less time than the narrower vessels (14 d) formed in May.These findings reveal distinct cell‐type‐dependent mechanisms for differentiation in diffuse‐porous and ring‐porous trees, enhancing our understanding of angiosperm wood cell kinetics. Our approach presents an effective method for investigating angiosperm wood formation and provides a more accurate representation of vessel and fiber morphogenesis in wood formation models. [ABSTRACT FROM AUTHOR]

• TiO 2 -PVDF fiber film has the hierarchical structure as sky radiative cooling material. • TiO 2 -PVDF fiber are prepared by the polymer assisted electrospinning technique. • The TiO 2 -PVDF fiber film possesses high solar reflectivity of 99.01% (Vis band), 97.20% (NIR band) and high emissivity of 89.91% in atmospheric window. • In the outdoor testing, the maximum sub-ambient cooling temperature of 6.9℃ under sunlight, and 4.4 ℃ at night are achieved. Radiative sky cooling is a passive cooling method without consuming any additional energy. Here, we propose a kind of hierarchically structural and particle-enhanced TiO 2 -PVDF fiber film as the radiative sky cooling material. TiO 2 -PVDF fibers are prepared by the polymer assisted electrospinning technique. The hierarchical structure encompasses polymer fibers, inorganic enhanced particles and pores formed by interlacing fibers. In this work, the effect of TiO 2 adding on the morphology, structure and spectral performance of hierarchically structural fiber film are discussed. By introducing the inorganic TiO 2 particles with high refractive index into polymer fiber matrix, the refractive index difference among the hierarchical structure can increase the scattering and solar reflectance, and phonon polariton resonance will increase the infrared emission. The obtained TiO 2 -PVDF fiber film possesses the optimal high solar reflectivity of 99.01% (Vis band), 97.20% (NIR band) and infrared emissivity of 89.91% within the atmospheric window band. In outdoor testing in Wuhan (temperate climate) during October, the maximum sub-ambient cooling temperature under sunlight can reach 6.9℃, and 4.4℃ at night. Thus, this TiO 2 -PVDF fiber film can become a promising all-day cooling and energy saving material. Furthermore, it can be used in the more cooling and thermal management fields to greatly improve the comfortability of people's living and life. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) is one of the most commercially used thermoplastics, while a significant amount of PP is used in the form of fibers. In this study, the effects of modification of the filler on the thermal and mechanical properties of composite polypropylene/wollastonite drawn fibers were investigated. In this direction, the surface modification of wollastonite with various organic acids, such as myristic, maleic, malonic glutaric, pimelic, and suberic acid, and the use of two solvents were studied. The surface-modified wollastonite particles were used to produce composite polypropylene drawn fibers. The modification efficiency was found to be slightly better when a non-polar solvent (carbon tetrachloride) was used instead of a polar one (ethanol). FTIR experiments showed that myristic, maleic, malonic, and pimelic acid can strongly interact with wollastonite's surface. However, the mechanical strength of the composite fibers was not increased compared to that of the neat PP fibers, suggesting inadequate interactions between PP and wollastonite particles. Furthermore, it was observed that the drawing process increased around 10% the crystallinity of all samples. Wollastonite modified with malonic acid acted as a nucleating agent for β-crystals. The onset decomposition temperature increased by 5–10 °C for all samples containing 2% wollastonite, either modified or not. The suggested modifications of wollastonite might be more suitable for less hydrophobic polymers. [ABSTRACT FROM AUTHOR]

The present work is focused on the preparation and characterization of composite nano/microfibers based on alumina applicable as fillers in ceramic-matrix composites. The graphene-coated Al 2 O 3 microfibers have been prepared in the form of continuous alumina/graphene fibers from electrospun precursors using needle-less electrospinning, calcination, and catalyst-free chemical vapor deposition of graphene layers on the surface of the microfibers. The phase composition and morphology of the composite fibers were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, scanning, and transmission electron microscopy (SEM and TEM). The porosity of the final fibers was evaluated by low-temperature nitrogen adsorption. The surface microstructures of composite fibers were rough and their diameters were in the range from 300 nm to 2 μm. The phase transformation at 1100 °C led to the formation of a mixture of γ-, δ-, and α-Al 2 O 3. TEM results confirmed that the alumina fibers were covered by the 3–4 layers of graphene-based structure. The specific surface area of pure alumina fibers after carbon deposition slightly increased from the initial 40 m2/g to 45 m2/g, due to a slightly wavy surface of graphene layers. Raman spectroscopy and XPS analysis results showed that the surface layer of fibers is formed as graphene oxide. Between the graphene oxide and alumina grains a chemical bonding C–O–Al, C–O–O–Al was discovered as the nucleation of the graphene oxide sheet. The growth mechanism of graphene oxide layers on the surface edges of Al 2 O 3 grains was described. [ABSTRACT FROM AUTHOR]

Crohn's disease (CD) is a subtype of inflammatory bowel disease (IBD). CD is a health problem in Western countries such as the US and European nations and is an idiopathic disease; however, certain cases of CD have been associated with intestinal dysbiosis. A systematic review with a meta-analysis was carried out to determine the efficacy of a diet rich in fiber with or without cointervention to improve remission rates for CD. The literature in the PubMed, Scopus, Web of Science, and ClinicalTrials databases was reviewed. The quality of the studies was evaluated using the Johanna Briggs Institute (JBI) scale. This review was conducted in accordance with the structure outlined in the PRISMA statement. In addition, a meta-analysis was performed with a 95% confidence interval (CI) and a random effects model. Eleven studies were included, totaling 2389 patients with CD. Applying a diet rich in fiber with or without the administration of routine therapies improved CD remission rates. Data regarding CD activity, remission time, and adverse effects derived from fiber consumption were analyzed. Consumption of fiber in the diet could improve remission rates for CD patients who receive or do not receive other treatment to maintain remission. [ABSTRACT FROM AUTHOR]

Biosupercapacitors (BSCs) that can harvest and store chemical energy show great promise for power delivery of biological applications. However, low power density still limits their applications, especially as miniaturized implants. Here, we report an implantable fiber BSC with maximal power density of 22.6 mW cm−2, superior to the previous reports. The fiber BSC was fabricated by integrating anode and cathode fibers of biofuel cell with supercapacitor fibers through multi‐strand twisting. This twisting structure endowed many channels inside and high electrochemical active area for efficient mass diffusion and charge transfer among different fibers, benefiting high power output. The obtained thin and flexible fiber BSC operated stably under deformations and performed high biocompatibility after implantation. Eventually, the fiber BSC was implanted subcutaneously in rats and successfully realized electrical stimulation of sciatic nerve, showing promise as a power source in vivo. [ABSTRACT FROM AUTHOR]

Asbestos has been classified as a human carcinogen, and exposure may increase the risk of diseases associated with impaired respiratory function. As the range of health effects and airborne concentrations that result in health effects across asbestos-related natural mineral fiber types are not fully understood, the National Institute of Environmental Health Sciences has established a series of research studies to characterize hazards of natural mineral fibers after inhalation exposure. This paper presents the method development work of this research project. A prototype nose-only exposure system was fabricated to explore the feasibility of generating natural mineral fiber aerosol for in vivo inhalation toxicity studies. The prototype system consisted of a slide bar aerosol generator, a distribution/delivery system and an exposure carousel. Characterization tests conducted using Libby Amphibole 2007 (LA 2007) demonstrated the prototype system delivered stable and controllable aerosol concentration to the exposure carousel. Transmission electron microscopy (TEM) analysis of aerosol samples collected at the exposure port showed the average fiber length and width were comparable to the bulk LA 2007. TEM coupled with energy dispersive spectrometry (EDS) and selected area electron diffraction (SAED) analysis further confirmed fibers from the aerosol samples were consistent with the bulk LA 2007 chemically and physically. Characterization of the prototype system demonstrated feasibility of generating LA 2007 fiber aerosols appropriate for in vivo inhalation toxicity studies. The methods developed in this study are suitable to apply to a multiple-carousel exposure system for a rat inhalation toxicity testing using LA 2007. [ABSTRACT FROM AUTHOR]

Exposure to asbestos is associated with malignant and nonmalignant respiratory disease. To strengthen the scientific basis for risk assessment on fibers, the National Institute of Environmental Health Sciences (NIEHS) has initiated a series of studies to address fundamental questions on the toxicology of naturally occurring asbestos and related mineral fibers after inhalation exposure. A prototype nose-only exposure system was previously developed and validated. The prototype system was expanded to a large-scale exposure system in this study for conducting subsequent in vivo rodent inhalation studies of Libby amphibole (LA) 2007, selected as a model fiber. The exposure system consisting of six exposure carousels was able to independently deliver stable LA 2007 aerosol to individual carousels at target concentrations of 0 (control group), 0.1, 0.3, 1, 3, or 10 mg/m3. A single aerosol generator was used to provide aerosol to all carousels to ensure that exposure atmospheres were chemically and physically similar, with aerosol concentration as the only major variable among the carousels. Transmission electron microscopy (TEM) coupled with energy dispersive spectrometry (EDS) and selected area electron diffraction (SAED) analysis of aerosol samples collected at the exposure ports indicated the fiber dimensions, chemical composition, and mineralogy were equivalent across exposure carousels and were comparable to the bulk LA 2007 material. The exposure system developed is ready for use in conducting nose-only inhalation toxicity studies of LA 2007 in rats. The exposure system is anticipated to have applicability for the inhalation toxicity evaluation of other natural mineral fibers of concern. [ABSTRACT FROM AUTHOR]

The development of microcrystalline cellulose from banana flower pistil and its twill weaved woven abaca polyester composites were studied in this research. The aim of this research was to explore the viscoelastic, fatigue, and mechanical behavior of surface‐treated twill weaved abaca fiber and unsaturated polyester incorporating banana flower pistil cellulose particles for various composite combinations. Hand layup process was used to construct the bio‐composite laminates, which were then tested in accordance with american society for testing and materials (ASTM) standards. The maximum tensile strength and modulus, flexural strength and modulus, Izod impact strength, as well asinter laminar shear strength (ILSS) values by addition of 3.0 vol% of cellulose were about 124 MPa, 4.48 GPa, 163 MPa, 5.36 GPa, 5.33 J/m2, and 27 MPa respectively, whereas composite having 5.0 vol% of cellulose gave better hardness of 82 shore‐D. Incorporation of cellulose by 3.0 vol% with 50 vol% of abaca fiber increases fatigue life counts up to 35,480, 29,039, 24,802, and 18,247 for 25%, 50%, 70%, and 90% of ultimate tensile strength (UTS) respectively. On comparing all other composite combinations, the composite containing 3.0 vol% of cellulose shows the highest storage modulus of up to 5.6 GPa and the lowest loss factor of 0.38. The scanning electron microscopy (SEM) fractography shows the improved adhesion between fiber and matrix due to the silane treatment on cellulose and abaca fiber. These novel functional materials could be employed in a large range of applications, including industrial, automobile, electronic and household equipment. [ABSTRACT FROM AUTHOR]

Fiber reinforced polymer composites (FRPCs) have gained great progress in a wide range of applications from construction and building structures to automobile and vehicle systems. During the operational lifetime, some FRPCs are exposed to various environmental conditions such as thermal cycles and thermal shocks. Fluctuation of the ambient temperature in the forms of thermal shocks or thermal cycles is one of the most important factors that deteriorate the durability and performance of the FRPCs. Compared to ceramic composites, less attention has been paid to the effects of thermal shocks and thermal cycles on the physical/mechanical properties of FRPCs. A comprehensive insight for the future advancements in this field is essential to possibly reduce the failure risks of FRPCs under thermal shocks and thermal cycles. The present work provides a comprehensive review on the physical/mechanical behavior of FRPCs under thermal cycles and thermal shocks. This work also provides a broad review on several factors that determines mechanical behavior of FRPCs, such as polymeric matrix, fiber type, incorporated nanofillers and fiber/polymer interface. Recent studies denoting important aspects and possible problems in mechanical performance of FRPCs under thermal shocks are also summarized. [ABSTRACT FROM AUTHOR]

In open environment applications, fibers are increasingly being used that are expected to biodegrade in the soil after their desired service life. Biodegradable polymer fibers are a versatile alternative to natural fibers. In this study, the degradation behavior of fibers made from polylactic acid (PLA) and a polyhydroxy alkanoate (PHA) blend with PLA, as well as a bicomponent fiber (BICO) made from polybutylene succinate (PBS) and PLA, was investigated. The fibers were stored in topsoil at 23 °C for 12 weeks. In addition, fibers were stored in compost at 58 °C for 4 weeks to investigate the degradation behavior in an industrial composting plant. Reference materials were also stored without substrate under the same temperatures and humidity conditions. Samples were taken regularly, and mechanical testing, scanning electron microscopy (SEM), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and infrared spectroscopy (IR) were used to study the degradation of the fibers. After 12 weeks in soil at ambient temperatures, the PLA and BICO fibers showed no degradation. The PHA fibers showed cracks in SEM, a decrease in molecular weight, and changes in the IR spectrum. No evidence of biological influence (bacteria or fungi) was found. Under industrial composting conditions, all fibers showed a decrease in strength and molecular weight. For the BICO and the PHA fibers, the SEM images show significant changes. Especially in the PHA fibers, fungal mycelia can be seen. The studies provide a better insight into the processes involved in the degradation behavior under different environmental conditions. [ABSTRACT FROM AUTHOR]