Статті в журналах: "Plant fibers Testing"

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Hamad, Sameer F., Nicola Stehling, Simon A. Hayes, Joel P. Foreman, and C. Rodenburg. "Exploiting Plasma Exposed, Natural Surface Nanostructures in Ramie Fibers for Polymer Composite Applications." Materials 12, no. 10 (May 18, 2019): 1631. http://dx.doi.org/10.3390/ma12101631.

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Nanoscale surface morphology of plant fibers has important implications for the interfacial bonding in fiber-polymer composites. In this study, we investigated and quantified the effect of plasma-surface modification on ramie plant fibers as a potential tool for simple and efficient surface modification. The extensive investigation of the effects of plasma treatment of the fiber surface nano-morphology and its effect on the fiber-polymer interface was performed by Low-Voltages Scanning Electron Microscopy (LV-SEM), infrared spectroscopy (FT-IR) analysis, fiber-resin angle measurements and mechanical (tensile) testing. The LV-SEM imaging of uncoated plasma treated fibers reveals nanostructures such as microfibrils and elementary fibrils and their importance for fiber mechanical properties, fiber wettability, and fiber-polymer matrix interlocking which all peak at short plasma treatment times. Thus, such treatment can be an effective in modifying the fiber surface characteristics and fiber-polymer matrix interlocking favorably for composite applications.

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Anil Kumar, V., T. Sai Neeraj, and Y. Meghana. "Mechanical Characterization and Fabrication of Banana and Pineapple Fibers." IOP Conference Series: Materials Science and Engineering 1248, no. 1 (July 1, 2022): 012061. http://dx.doi.org/10.1088/1757-899x/1248/1/012061.

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Abstract A composite material is made up of two or more materials with differing properties that are combined to enhance material properties. Various natural fibers are abundant in India such as seed hairs like cotton, flax, hemp leaf fibers, sisal, coconut, jute, pineapple, luffa, etc. Since natural fibers stand-alone don't have distinct mechanical properties. To attain good mechanical properties and to explore worth-added applications. The evolvement of natural fiber composites in India is to avoid the depletion of resources. The reason for the desirability of this field over the traditionally used synthetic fiber is that natural fibers have low density, high toughness, are environment friendly, fully biodegradable, renewable, and low cost. The biodegradability of plant fibers can impart a healthy ecosystem while their low cost & high performance fulfill the economic interest of industries. The purpose of this paper is to develop a new natural fiber composite with banana stem fibers and pineapple fibers. Resins and hardeners are chosen depending on the mechanical properties of the fibers, and fabrication was done accordingly. Finally, conclusions are drawn after Mechanical Testing of the composites. The properties of the composites are discussed.

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Arivendan, Ajithram, Winowlin Jappes J T, Siva Irulappasamy, and Brintha N Chris. "Water hyacinth (EichhorniaCrassipes) polymer composites properties - aquatic waste into successful commercial product." Metallurgical and Materials Engineering 28, no. 1 (March 25, 2022): 157–69. http://dx.doi.org/10.30544/752.

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In modern times, the demand for natural fibers is increased due to low density, low cost, recyclability, and biodegradable properties. Following work deals with the aquatic waste of water hyacinth plant fiber. The main intent of this work is to utilize the hyacinth plant into a successive manner and convert this plant into some commercial products. It is used as reinforcement material and epoxy polymer resin in matrix material with a suitable percentage of hardener (10:1). A new method such as a mechanical way of extraction process is introduced in this work. The different weight percentage of the hyacinth fiber is reinforced with matrix material like 15, 20, 25, 30, and 35%. With the help of a compression molding, machine water hyacinth reinforced fiber composite is produced by using 1500 PSI pressure and 110 °C, 100 °C of upper and lower plate temperature. A composite sample is cut into as per ASTM standards and the mechanical tests like tensile, flexural, impact test is conducted by using universal testing machine (UTM), and Charpy impact test machine. Based on the final mechanical test results, the 30% of hyacinth composite sample tensile 36.48 MPa, flexural 48.62 MPa, impact 0.5 J, and hardness 98 attained then, the hyacinth composite samples are adopted into water and chemical absorption test with 10 hours, 1week, 1month of continuous monitoring. Based on the final results, hyacinth fiber is strongly recommended to use an alternative of synthetic fibers and conventional natural fibers. The hyacinth composite is strongly recommended for the usage of commercial and household applications.

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Kumar, R., R. Jyothilakshmi, and H. L. Nandeesha. "Synthesis and testing for mechanical integrity of nano cellulose composites." Journal of Mines, Metals and Fuels 69, no. 12A (April 28, 2022): 37. http://dx.doi.org/10.18311/jmmf/2021/30092.

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This scientific research focused on extraction of the polymer from an appropriate source and preparation of films with mechanical integrity and desirable chemical properties. Reinforcement of said films with nano-fillers like Nano silica and clay were administered to reinforce their mechanical properties. Further development on these films would contribute to eliminating plastics and replacing them with better and sustainable materials. Cellulose may be a biopolymer found in plant cell walls which will be derived from biomass sources like sugarcane. It is one among the main constituents of plant cell walls alongside hemicellulose and lignin. “Cellulose consists of long unbranched fibers of glucose held together by hydrogen bonds”. It is widely utilized in paper, plastics, coatings and casings.

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Rusmini, Dwinita Aquastini, Riama Rita Manullang, Daryono Daryono, Ali Sadikin, and Hadi Kuncoro. "PHYTOCHEMICAL ASSAY AND ANTIOXIDANT ACTIVITY AGAINST DPPH OF ETHANOL EXTRACT FROM KENAF LEAF (Hibiscus cannabinus L.)." Journal of Tropical Pharmacy and Chemistry 4, no. 5 (June 30, 2019): 203–8. http://dx.doi.org/10.25026/jtpc.v4i5.202.

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Kenaf (Hibiscus cannabinus L.) is an environmentally friendly natural fiber-producing plant that can produce diversified products, such as paper, wallcover, car interior, geotextile, soil safer, fiber drain, particle board, and plastic reinforcement as well as biofuel industry raw materials. Kenaf plant is a plant that has been only part of the fibers of the stem alone so that many unprofitable side products such as kenaf leaves after harvesting only as a waste. In Africa the leaves of kenaf are widely used as medicine This study aims to analyze phytochemical compounds and study the antioxidant activity of the kenaf leaf. The study started by doing phytochemical test and analyzing antioxidant in kenaf leaf and then testing its antioxidant activity with DPPH method. The results showed that the leaves of kenaf contain secondary metabolites of phytochemical compounds such as flavonoids, alkaloids, steroids, saponins, carbohydrates and tannins and have antioxidant activity that is quite good that is 44.4813 ppm.

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Koronis, Georgios, Arlindo Silva, and Michael Ong. "Comparison of Structural Performance and Environmental Impact of Epoxy Composites Modified by Glass and Flax Fabrics." Journal of Composites Science 6, no. 10 (September 27, 2022): 284. http://dx.doi.org/10.3390/jcs6100284.

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Comparing the structural performance and environmental impact of parts made of natural and synthetic fibers has become increasingly important for industry and education, as the benefits of one type of fiber over another are not always clear. The current work discusses the advantages and disadvantages of using natural and synthetic fibers and compares the flexural performance of parts made of each of these fibers and their environmental impact. This paper investigates the flexural behavior of epoxy composites modified by glass and flax fabrics through experimental, numerical, and analytical studies. Specimens with various fabrics (dried and non-dried) were fabricated to test their performance. The failure of unidirectional glass and flax fiber reinforced polymer composite laminate was examined by destructive testing. A finite-element model was developed, and the mechanical behaviors of fiber-reinforced composites were predicted in a three-point bending test. Experimental results were compared to numerical analysis to validate the model’s accuracy. A life cycle assessment (LCA) was employed to determine the climate impact of composite production. The analysis revealed a decreased environmental effect of plant-based panels suggesting that they are less energy and CO2 intensive than synthetic solutions. The LCA model can be applied in further studies of products that consist of or use flax-based composites.

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Machaka, Meheddene, Jamal Khatib, Safaa Baydoun, Adel Elkordi, and Joseph J. Assaad. "The Effect of Adding Phragmites australis Fibers on the Properties of Concrete." Buildings 12, no. 3 (March 1, 2022): 278. http://dx.doi.org/10.3390/buildings12030278.

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Nowadays, the increasing demand for concrete is causing serious environmental impact including pollution and waste generation, rapid depletion of natural resources, and increased CO2 emission. Incorporating natural fibers in concrete can contribute toward environmental sustainability. This paper is concerned with the use of natural fibers obtained from the plant species Phragmites australis (PA). The plant is invasive, and rapidly grows abundantly along rivers and waterways, causing major ecological problems. This research is part of a wide range investigation on the use of natural fibers produced from the stem of PA plants in concrete. Using a machine, plant stems were crushed into fibers measuring 40 mm in length and 2 mm in width, and treated with 4% NaOH solution for 24 h. A total of four concrete mixes were prepared with varying additions of treated fibers, ranging from 0% to 1.5% (by volume) with water to cement ratio of 0.5% (by volume). Concrete specimens were tested at 3, 7, and 28 days. Testing included compressive strength, density, total water absorption, and capillary water absorption. The results show that incorporating PA natural fibers reduces the water absorption by total immersion and capillary action by up to 45%. Moreover, there is a negligible decrease in concrete density and strength when fibers were added. It is concluded that adding up to 1.5% natural PA fibers to concrete is a feasible strategy to produce an eco-friendly material which can be used in the production of sustainable building material with adequate mechanical and durability performance.

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FERRAZ, RENER LUCIANO DE SOUZA, PATRÍCIA DA SILVA COSTA, IVOMBERG DOURADO MAGALHÃES, PEDRO ROBERTO ALMEIDA VIÉGAS, JOSÉ DANTAS NETO, and ALBERTO SOARES DE MELO. "PHYSIOLOGICAL ADJUSTMENTS, YIELD INCREASE AND FIBER QUALITY OF 'BRS RUBI' NATURALLY COLORED COTTON UNDER SILICON DOSES." Revista Caatinga 35, no. 2 (June 2022): 371–81. http://dx.doi.org/10.1590/1983-21252022v35n213rc.

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ABSTRACT Globally, the demand for food and consumer products has accompanied population growth, forcing the agriculture and livestock sector to optimize the production systems. In the specific case of agriculture, using improved edible and energetic plant cultivars associated with abiotic stress-reducing substances is a strategy adopted to solve this problem. This investigation aimed to evaluate whether silicon (Si) promotes physiological adjustments, an increase in production, higher yield, and improved quality of naturally colored cotton fibers. Five doses of silicon (0 (control), 5, 10, 15, and 20 kg ha−1) were tested in a completely randomized design. The variables assessed were physiological adjustments, production, yield and quality of fibers produced by BRS Rubi cultivar. Data were submitted to principal component analysis, multivariate and univariate analyses of variance, and multiple linear regression analysis. Silicon promotes physiological adjustments, enhanced production, yield, and quality of naturally colored cotton fibers of BRS Rubi cultivar grown in the Brazilian semiarid region. Fiber quality in plants that have been treated with Si is within the expected values for this cultivar and by the international standard D-4605 of the American Society for Testing and Materials. 10 kg ha−1 of Si is recommended to increase fiber quality of naturally colored cotton cv. BRS Rubi.

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Ramu, S., and N. Senthilkumar. "Approaches of material selection, alignment and methods of fabrication for natural fiber polymer composites: A review." Journal of Applied and Natural Science 14, no. 2 (June 18, 2022): 490–99. http://dx.doi.org/10.31018/jans.v14i2.3351.

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The recent superiority of the composite materials is cautiously focusing on environmental adoption of natural fiber composites. The major source of the natural fiber materials covered in the globe, especially natural fibers, is plant-based, animal-based and mineral-based. Eco friendly based material can save the environment and recycling of the material is possible, as well as important criteria. Hence engineers ultimately focused on natural fiber polymer matrix materials to save the environment, pollution control, plastic manipulation, etc. The literature work was studied to identify natural fiber material possession. The major goal of the present review was to identify material characterization and appropriate application, mainly offering to enhance mechanical properties, flexural strength, electrical properties, thermal properties etc. The major consequence of the natural fiber is hydrophilic treatment. There is poor interfacial adhesion between the addition/filling substances and poor mechanical characteristics. All of these shortcomings constitute a critical issue. This review presents numerous sorts of natural and synthetic polymers, natural fibres such as jute, ramie, banana, pineapple leaf fibre, and kenaf, etc.; short and long fibre loading methods, fibre fillers in micro and nanoparticle, American society of testing and materials (ASTM) standard plate dimensions, fabrication methods such as hand lay-up process, spray lay-up process, vacuumed-bag, continuous pultrusion, and pulforming process, etc.; industries and home appliances such as automotive parts, building construction, sports kits, domestic goods, and electronic devices. The review lists various material combinations, fibre loading, fillers, and matrix that can aid in the improvement of material properties and the reduction of failures during mechanical testing of composites.

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Obi LE, Uwanugo RG, and Uchejiora M. "Investigation of water and heat response to the compression property of raffia, bamboo and coconut fiber-reinforced-polyester composites." International Journal of Frontiers in Engineering and Technology Research 1, no. 1 (November 30, 2021): 045–60. http://dx.doi.org/10.53294/ijfetr.2021.1.1.0045.

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The dearth of construction materials has been the bane of the global construction industry. In a bid to curb this menace, it becomes very imperative to source for construction materials from discarded and least costly materials from raffia, bamboo and coconut fibers. This research investigates the hydrothermal response of plant fiber-reinforced-polyester composites (PFRC). Imperical methods were used to determine the mechanical properties of PFRC (bamboo, raffia and coconut fiber composites), with the usage of Monasanto Tensometer testing machine. All the samples were chemically modified with 12.5g of sodium hydroxide. Numerical and micro-soft excel graphics were used to model compressive responses of the PFRCs. From the analyses, the compressive strengths of raffia, bamboo and coconut composites are 40, 45 and 38MPa respectively.

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Cheymol, G., L. Maurin, L. Remy, V. Arounassalame, H. Maskrot, S. Rougeault, V. Dauvois, et al. "Tests under irradiation of optical fibers and cables devoted to corium monitoring in case of severe accident in a Nuclear Power Plant." EPJ Web of Conferences 225 (2020): 08006. http://dx.doi.org/10.1051/epjconf/202022508006.

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The DISCOMS project, which stands for “DIstributed Sensing for COrium Monitoring and Safety”, considers the potential of distributed sensing technologies, based on remote instrumentations and Optical Fiber Sensing cables embedded into the concrete floor under the reactor vessel, to monitor the status of this third barrier of confinement. This paper focuses on the selection and testing of singlemode (SM) optical fibers with limited RIA (Radiation Induced Attenuation) to be compliant with remote distributed instruments optical budgets, the ionizing radiation doses to sustain, and their reduction provided by the concrete basemat shielding. The tests aimed at exposing these fibers and the corresponding sensitive optical cables, to the irradiation doses expected during the normal operation of the reactor (up to 60 years for the European Pressurized Reactor), followed by a severe accident. Several gamma and mixed (neutron-gamma) irradiations were performed at CEA Saclay facilities: POSÉÏDON irradiator and ISIS reactor, up to a gamma cumulated dose of about 2 MGy and fast neutron fluence (E > 1 MeV) of 6 x 1015 n/cm2. The first gamma test permitted to assess the RIA at various optical wavelengths, and to select three radiation tolerant singlemode fibers (RIA < 5 dB/100 m, at 1550 nm operating wavelength). The second one was performed on voluminous strands of sensitive cables encapsulating the selected optical fibers, up to approximately the same accumulated dose, at two temperatures: 30°C and 80°C. A significant increase of the RIA, without any saturation tendency, appeared for fibers inserted into cables, correlated with the increase of the hydroxyl attenuation peak at 1380 nm. Molecular hydrogen generated by the radiolysis of compounds of the cable is at the origin of this phenomenon. A third gamma irradiation run permitted to measure the radiolytic hydrogen production yield of some compounds of a dedicated temperature cable sample. The efficiency of a carbon coating layer over the silica cladding, acting as a barrier against hydrogen diffusion, was also successfully confirmed. Finally, the efficiency of this carbon coating layer has also been tested under neutron irradiation, then qualified as a protection barrier against hydrogen diffusion in the optical fiber cores.

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Pang, Li guo, Lei Yu, Ming ming Chai, and Biao zhi Zhang. "Anti-cracking Technology and Application of Fiber Reinforced Concrete on Bridge Deck Pavement." E3S Web of Conferences 233 (2021): 01041. http://dx.doi.org/10.1051/e3sconf/202123301041.

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In order to make the bridge deck pavement not easy cracking, the anti-cracking technology is put into effect on a certain bridge. The cementing material is selected after analyzing the theory that how fiber can enhance the concrete anti-cracking performance. The proper fiber is selected by testing and comparing the dispersibility and hydroscopicity of three kinds of fibers. The proper content of fiber is found by test and comparing different fiber contents in the same mix proportion concrete. The fiber is sent into the in forced-mixing concrete plant by spreading the fiber on the crawler belt. The construction technology including slab treatment, transport, pave, vibrate and curing is put forward. After 1 year observing, there is no any cracking on the bridge deck pavement. The life of bridge is increased. The cost of maintain is decreased. The goal of anti-cracking has been achieved.

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Ahsan, Qumrul, Chia Pooi Ching, and Mohd Yuhazri bin Yaakob. "Physical and Sound Absorption Properties of Spent Tea Leaf Fiber Filled Polyurethane Foam Composite." Applied Mechanics and Materials 660 (October 2014): 541–46. http://dx.doi.org/10.4028/www.scientific.net/amm.660.541.

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Spent tea leaves (STL) from tea producing factories can be considered as new resources for sound absorbing polyurethane (PU) matrix composite materials because STL are rich in polyphenols (tannins) which cause high durability, high resistance to fungal and termites, and high resistance to fire. The research aims to study the physical characteristics of STL and the effect of dispersion morphology of STL on the sound absorption properties of polyurethane foam composites by varying filler loading. Three grades of STL fibers either as received or granulated are used in this study, namely BM-FAE and SWBHE derived from the stalk while FIBER-FAE derived from the leaves of the tea plant. The PU/STL composites are fabricated through open molding method with a fiber loading of 16 wt. %. The fabricated composites are then subjected to physical and sound absorption testing as well as microscopic observations to analyze the distribution of filler in composite. The study shows that as-received FIBER-FAE spent tea leaves provide the best sound absorption coefficient and for composites using granulated fibers from any grade have lower sound absorption coefficient. These results show that a novel kind of sound absorption materials with the recycling of waste materials can be obtained for the solution of noise and environmental pollution.

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Divya, D., I. Jenish, and S. Raja. "Comprehensive Characterization of Furcraea selloa K. Koch Peduncle Fiber-Reinforced Polyester Composites—Effect of Fiber Length and Weight Ratio." Advances in Materials Science and Engineering 2022 (May 10, 2022): 1–10. http://dx.doi.org/10.1155/2022/8099500.

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Nowadays, scientists and researchers working on polymer composites are paying much attention to the discovery of prospective plant fibers in order to build a promising fiber-reinforced polymer composite. The present study investigated the efficacy of using a novel Furcraea selloa K. Koch peduncle fiber in reinforced composites, and the specific composite characterization was done to explore the absolute fiber length and weight ratio to accomplish superior composite properties. For that, peduncle fibers with different length-to-weight ratios were reinforced with unsaturated polyester and the corresponding composites were tested to decide the optimum fiber length-to-weight ratio for obtaining the utmost composite properties. The results indicated that the highest mechanical properties were allied with a composite reinforced with 30 mm fiber length and 30 wt.% with the tensile strength of 103.51 MPa and flexural strength of 144.65 MPa. While the remaining tested volumes showed decreased properties as compared to optimal, which might be due to debonding effects or less interfacial bonding as examined clearly in SEM images of fractured samples. Enhanced thermal stability with 390°C and relatively reduced water absorption rate was observed in the case of optimal range when compared to other testing dimensions. Moreover, the current study confirmed that FSPF composites possess promising comparable properties which would be a good alternative to existing synthetic composites.

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Sun, Ying, Duanxin Li, Yang Yu, Jialin Chen, and Wanyue Fan. "Separation and Characterization of Cellulose Fibers from Cannabis Bast Using Foamed Nickel by Cathodic Electro-Fenton Oxidation Strategy." Polymers 14, no. 3 (January 19, 2022): 380. http://dx.doi.org/10.3390/polym14030380.

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Degumming is the most important link in the textile industry. The main purpose of degumming is to effectively remove non-cellulose substances in plant bast fibers. In this research, we propose an electro-Fenton (EF) system with a nickel-foam (Ni-F) cathode in weak acid pH (EF/Ni-F) to degum cannabis fiber in EF while reducing the content of pollutants in degumming wastewater. FT-IR, XPS, XRD, SEM, and TG were employed to thoroughly understand the reaction characteristics to characterize chemical components, element qualities, the crystallinity, and the morphologies of degummed fibers. Additionally, physical and mechanical properties such as breaking strength, elongation at breaking, residual glue rate, whiteness, and diameter of degummed fibers were measured. Through testing, it was found that the fiber degummed by the EF method had higher breaking strength, lower residual tackiness, and higher whiteness than other methods. The antibacterial test was used to detect the effect of fiber on Staphylococcus aureus before and after degumming. EF could remove more colloidal components from cannabis than other methods, and the mechanical properties were also enhanced. The characteristics of the degummed fiber further confirmed the effectiveness of the new degumming method. Moreover, the antibacterial experiment found that the antibacterial property of the degummed fiber was enhanced. The colloidal components in the degumming wastewater were flocculated and precipitated. The upper liquid of the solution had low chromaticity, low COD value, and weak acid pH value, which can meet the discharge requirements. The above test proves that EF is an effective degumming method that is environmentally friendly, takes less time, and enhances antibacterial performance.

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Fonteles, Carlos Alberto Lopes, Gustavo Figueiredo Brito, Laura Hecker Carvalho, Tatianny Soares Alves, and Renata Barbosa. "Composites Based on Thermoset Resin and Orbignya phalerata (Babassu Coconut): Evaluation of Mechanical Properties, Morphology and Water Sorption." Materials Science Forum 869 (August 2016): 237–42. http://dx.doi.org/10.4028/www.scientific.net/msf.869.237.

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Researches in plant fiber composites have been developed with greater frequency during the last years, especially on environmental issues. The opening of the market, especially in the automotive sector, points to the replacement of synthetic additives by natural reinforcements. Characteristics such as low density and abrasiveness, superior mechanical properties and low cost are the most sought in these composites. The aim of this study was to evaluate the behavior of composites based polyester matrix and fiber of the babassu coconut epicarp, at levels of 5, 7.5 and 10% under testing of tensile strength and impact, as well as the morphology by microscopy scanning electron and water absorption. All composites were prepared raw fibers and fiber with treated with alkaline solution of 5% NaOH. As regards the mechanical properties, an increasing of the rigidity of the system was observed, and the kinetics of water absorption increased levels indicated for compounds with high content of fibrous reinforcement. By SEM there was greater interaction between fiber and matrix.

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Priyanto, Agus. "Laminasi Kayu Sengon Sebagai Salah Satu Solusi Ketersediaan Kayu Untuk Bahan Bangunan." TAMAN VOKASI 7, no. 2 (December 26, 2019): 182. http://dx.doi.org/10.30738/jtv.v7i2.6307.

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Abstracts. The supply of wood that is quite durable and of high quality has not been able to meet the needs of building construction at the present time, especially in the future. Sengon wood (Paraserianthes falcataria) is a fast-growing type of plant that has a large increase (volume of wood per hectare per year) which is around 28 - 48 m3 / ha / year. To fulfill various human objectives, the majority of Sengon wood can be collected from the age of 6 years. With the use of lamination technology, wood remnants can be utilized to be made into wooden blocks of various sizes and various shapes. Lamination can make the strength of Sengon wood higher than solid wood beams.The test is carried out by physical and mechanical tests as well as the Sengon wood laminated sliding block test. In testing physical and mechanical properties based on ISO 1975 regulations. Testing of physical properties of Sengon wood includes wood density test and moisture content test. Testing the mechanical properties of Sengon wood includes fiber parallel compressive strength test, fiber perpendicular compressive strength test, tensile strength test, shear strength test and flexural strength test. Testing of Sengon wood laminated sliding blocks to determine the strength of lamination has a variation of 30 MDGL, 40 MDGL and 50 MDGL slurry adhesives with 3 replications of each shear test.The average density of Sengon wood is 0.315 t / m3 and the average moisture content of Sengon wood is 13.539%. The average compressive strength of fibers is 26.85 MPa and the compressive strength of fibers is 9.62 MPa. The average tensile strength of Sengon wood is 61.48 MPa and the average shear strength of Sengon wood is 5.31 MPa. In testing the flexural strength of Sengon wood an average of 43.18 MPa. Testing of Sengon wood laminate sliding block for 30 / MDGL obtained an average of 0.05 kg / mm2. In the shear block 40 / MDGL obtained an average shear strength of 0.02 kg / mm2. For the 50 / MDGL laminate shear block an average shear strength of 0.08 kg / mm2 was obtained.

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Ajithram, A., JT Winowlin Jappes, M. Adam Khan, and NC Brintha. "Evaluation of mechanical properties and thermal characteristics of aquatic waste water hyacinth (Eichhornia crassipes) plant into natural powder and ash reinforced polymer composites for lightweight applications." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 236, no. 7 (February 16, 2022): 3546–57. http://dx.doi.org/10.1177/09544062211038982.

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Contemporarily, natural fibers are considered as one of the important reinforcement materials as a consequence of their positive environmental productive characteristics like biodegradability, eco-friendliness, and nontoxicity. Mostly, natural fibers are used as commercial products towards lightweight materials and other applications. Most of the recent research works are closely related to aquatic and other natural fibers since they are considered to replace synthetic fibers. This research work focuses on the extraction process from water hyacinth plant into various commercial products by converting the hyacinth powder and ash particles with epoxy resin through the help of a compression molding machine. No work has to be done by using water hyacinth powder and ash reinforced polymer composites. The work samples were subjected to mechanical testing, thermal, TGA, DTA, SEM, elemental mapping, and chemical analysis. Mechanical strength of powder and ash composites varies from tensile 14.94 to 18.80 MPa, 18.91 to 28.6 MPa, and flexural 25.28 to 31.56 MPa, 23.08 to 45.704 MPa, and Impact 0.05 to 0.10 J, 0.10 to 0.15 J. Based on the final results obtained from this work the water hyacinth natural plant powder and ash can be used as reinforcement materials with an epoxy resin matrix that can be used for particleboard production and also other lightweight material products.

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Illya, Gregoria, and Ika Bali. "STUDI PERBANDINGAN SIFAT MEKANIK SERAT BAMBU." Jurnal Muara Sains, Teknologi, Kedokteran dan Ilmu Kesehatan 5, no. 2 (October 30, 2021): 383. http://dx.doi.org/10.24912/jmstkik.v5i2.10029.

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Natural fibers have application in almost every item used in our daily routine and been contributing explicitly to the economic prosperity and sustainability in our lives. Among the natural fiber plants, bamboo is the most popular, because of its versatile applications and significant contribution to the environment. Bamboo fibers have been used in various application such as decoration, weaving, paper makin, textile, and high-performance composites for the past many years. They have several advantages such as superior tensile strength, low density, and high flexibility under flexible and compressive loads. In order to meet the requirements of each bamboo application, there is a need to study the mechanical properties of bamboo fibers. This study reviews mechanical properties of bamboo fibers for various species, extraction methods, plant age, sizes, and moisture contents. Keywords: bamboo fiber; bamboo extraction method; mechanical properties; mechanical testing; tensile strength AbstrakIndonesia kaya akan tanaman yang dapat diambil seratnya untuk diolah menjadi produk yang bermanfaat. Di antara tanaman penghasil serat alami, bambu adalah yang paling populer, karena memiliki aplikasi yang serba guna, mudah tumbuh, tidak memerlukan perawatan dan dapat mengurangi pencemaran udara. Serat bambu telah digunakan dalam berbagai aplikasi seperti dekorasi, perabot, tekstil, kertas dan komposit. Beberapa keunggulan serat bambu adalah memiliki kekuatan tarik yang besar, densitas yang rendah dan fleksibilitas yang tinggi. Dalam rangka memenuhi persyaratan masing-masing aplikasi dari serat bambu, diperlukan studi mengenai sifat mekanik serat bambu. Penelitian ini membandingkan beberapa penelitian yang sudah dilakukan mengenai sifat mekanik serat bambu berdasarkan spesies, metode pengolahan dari batang bambu menjadi serat, umur tanaman, ukuran serat dan kadar kelembaban. Serat bambu yang dihasilkan dapat memiliki sifat mekanik yang optimal jika bambu yang dipilih adalah dari spesies tertentu, memiliki kadar kelembaban yang rendah dan menggunakan metode ekstraksi yang tepat.

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Razaq, Aamir, Asim Ali Khan, M. H. Asif, Shahid Iqbal, Jawad Ali, Faisal Manzoor, and M. S. Awan. "Dielectric studies of environmentally friendly and flexible lignocelluloses fibrils for miniaturization of patch antenna." Modern Physics Letters B 29, no. 30 (November 4, 2015): 1550187. http://dx.doi.org/10.1142/s0217984915501870.

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Naturally, existing lignocelluloses fibers showed outstanding potential in paper industry and other conventional applications. On the other hand, lignocellulose fibers are suitable candidate for high-tech applications under the scope of abundance, flexibility, light-weight and environment friendliness. In this study, paper sheets were prepared from lignocelluloses fibers extracted from self-growing plant, typha angustifolia. Lignocelluloses paper sheets were characterized for scanning electron microscopy (SEM), universal testing machine (UTM) and vector network analyzer (VNA). Flexible paper sheets displayed a tensile strength of 9.1 MPa and further used as a substrate in patch antenna to observe dielectric characteristics. The patch antenna is designed at 5.1 GHz which showed return loss less than −10 dB and dielectric constant 3.71. The use of lignocelluloses paper sheet as a substrate in patch antenna will provide the opportunity of miniaturization of size and weight in comparison of a jean substrate based antenna.

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Chu, Hong Yan, Jin Yang Jiang, Wei Sun, and Ming Zhong Zhang. "Mechanical Properties and Damage Evolution of Siliceous Concrete Subjected to Elevated Temperatures." Key Engineering Materials 711 (September 2016): 488–95. http://dx.doi.org/10.4028/www.scientific.net/kem.711.488.

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Siliceous concrete (SC) is applied in European Pressurized Water Reactor that is a key component of the third generation nuclear power plant. This paper investigates the mechanical properties and damage evolution of SC (with and without polypropylene fibers) exposed to high temperatures. The mass loss, compressive strength, splitting tensile strength and spalling sensitivity of SC before and after being heated to 200, 400, 600, 800, and 1000 °C are investigated. The ultrasonic testing technique was used to assess the thermal damage, by evaluating the variations of the ultrasonic wave velocity (UWV) for different temperature levels. According to the available literature, a new relationship between damage and UWV was proposed to establish a damage evolution model of SC. The results indicated that: (a) specimens without polypropylene (PP) fibers suffered severe spalling in the range 380-400°C and 470-510°C, while no spalling took place in the specimens with PP fibers in the whole range 25-1000°C; (b) the damage evolution with and without polypropylene fibers was similar, and could adequately be described by means of a Weibull distribution model.

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Starešinič, Marica, Bojana Boh Podgornik, Dejana Javoršek, Mirjam Leskovšek, and Klemen Možina. "Fibers Obtained from Invasive Alien Plant Species as a Base Material for Paper Production." Forests 12, no. 5 (April 24, 2021): 527. http://dx.doi.org/10.3390/f12050527.

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Invasive alien plant species (IAPS) are one of the biggest challenges in European ecosystems, displacing local vegetation, destroying agricultural land, and causing billions of dollars of damage to the European economy every year. Many of them are removed daily and mainly burned. In this work, we investigated the possibilities of using plants as feedstock for paper production. Papers made from three invasive alien plants, i.e., Knotweed, Goldenrod, and Black locust, were studied and compared with commercial office paper. The study included testing of: (1) structural properties—basic physical properties, grammage, thickness, density and specific volume, moisture content, and ash content; (2) physical and dynamic mechanical properties—tensile strength, Clark stiffness, viscoelastic properties; (3) colorimetric properties of prints; (4) effect of UV light on ageing; and (5) study of cellulose fiber structure and morphology by microscopy. The results suggested that the paper produced can be used as commercial office paper, considering that the paper is slightly dyed. Such papers can also be used for special purposes that present a natural style and connection to nature. The papers produced can also be used for printing documents that are meant to be kept.

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TARCEA, Monica, Zita FAZEKAS, Florina RUTA, Victoria RUS, Corina ZUGRAVU, and Raquel GUINE. "Romanian knowledge and attitudes regarding dietary fibers." Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Food Science and Technology 73, no. 2 (November 28, 2016): 123. http://dx.doi.org/10.15835/buasvmcn-fst:12329.

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Introduction: Presently, the scientists recognize the health benefits of food fibers in the menu and also plant food sources are at high interest both for general population and food companies. The food companies are responsible for a clear nutrition labelling that will assist consumers to make informed and healthy choices and health providers has to inform the population about the benefits of fibers. The aim of our study was to evaluate the Romanian knowledge and attitudes regarding dietary fibers from food products.Materials and methods: We made a qualitative survey based on a questionnaire applied in 2015, over a period of 6 months, over 670 Romanian consumers. It was focused on testing the attitudes and knowledge towards ingestion of foods rich in fibers. For all data analysis we used the software SPSS, from IBM Inc.Results and Discussions: Our results showed that the knowledge about dietary fibers and also the ingestion of food products rich in fibers were low, and most of the subjects didn’t have any interest to read the nutritional information from food labels related to fibers. The female participants ate more whole grains and fruits than males and pay more attention to food labelling, the Romanian people prefer to stay and eat home than at restaurants especially in rural areas, and the knowledge about fibers benefits was significantly related to education and urban location.Conclusion: We underline the needs for more efficient community interventions and proper information about the importance of dietary fibers for our health and also to improve and disseminate our nutritional standards and diet recommendation among population.

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Sinha, Dr A. S. K. "Moringa Oleifera as Fibrous Raw Material for Production of Handmade Paper and Packaging Materials." International Journal For Multidisciplinary Research 04, no. 04 (2022): 408–16. http://dx.doi.org/10.36948/ijfmr.2022.v04i04.044.

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The aim of this research paper is to find suitability of wood chips of Moringa Oleifera tree for paper and packaging materials as this plant is cultivated in large area of India and many other tropical and sub-tropical areas for its products like drum stick, leaves and seeds. Again, the tree is trimmed every year for better quality of its products. But the tree branches cut are mostly used as fuel material, so this biomass can be better utilized in production of natural cellulosic fibers having good fiber length and used in paper and packaging materials production. The study assessed the fiber characteristics of Moringa oleifera branches for pulp and paper production. Samples are collected from Moringa oleifera trees grown in nearby areas of Sangrur, Punjab. Moringa Oleifera has potential for the Paper Making as it has good fiber length, fiber length to diameter ratio, flexibility and very low percentage of ash. This is supported by relevant analysis of raw material along with several with testing of paper hand sheet samples prepared in paper technology lab. The plant has several medicinal, antibacterial, antioxidant properties, which can be further explored for making specialty paper and packaging materials. This beneficiation of the moringa tree biomass will increase the income of farmers and provide a new potential fibrous raw material for pulp and paper industries which is facing scarcity of good fiber length lignocellulosic raw materials.

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Ramful, Raviduth. "EVALUATION OF THE MECHANICAL PROPERTIES OF BAMBUSA BAMBOO LAMINATES THROUGH DESTRUCTIVE TESTING." Journal of Green Building 13, no. 4 (September 2018): 1–18. http://dx.doi.org/10.3992/1943-4618.13.4.1.

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In this research study, Bambusa ssp, the utilized species of bamboo, was rendered into a more versatile construction material in the form of laminates. The laminated specimens were manufactured using simplified processing methods according to the ASTM D3039 and ASTM D143 standards. Polyvinyl acetate was the adhesive used between the 2-ply laminate. The mechanical properties of the specimens were evaluated through tensile, compressive and bending strength tests according to set standards on the Testometric M500-50AT Universal Testing Machine. The tensile strength of laminated bamboo was comparable to that of redwood, spruce, cedar and pine. The ratio of compressive strength of parallel to perpendicular fibers in compressive tests was in a close range to that of poplar, fir and pine. The correlation in compressive strength values between bamboo and wood confirmed the inherent anisotropic nature of both plant materials.

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Umar, Muhammad Zakaria, and Abdul Fattaah Mustafa. "The performance optimization of concrete bricks using a sagu fiber." SINERGI 27, no. 1 (January 13, 2023): 7. http://dx.doi.org/10.22441/sinergi.2023.1.002.

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Sagu (sinonggi/kapurung) is a typical food of the Tolaki ethnic group. Sagu (Metroxylon sagu rottb) is an endemic plant in Southeast Sulawesi Province. So far, sagu waste in the form of fibers (sagu fiber) has not been optimally utilized. Sagu fiber waste is only left to mount; some are dumped into the river, so it is feared that it could pollute the environment. Through innovation in reducing waste in the principles of sustainable construction, sagu fiber will be used as an added material to manufacture concrete brick wall pairs. This study aimed to test the compressive strength and water absorption capacity of sagu fiber concrete bricks with variations of 0%, 50%, 60%, and 70% sagu fiber under the sand. This study uses an experimental method with stages such as preparing work tools and work materials, making test objects, and testing. Data were analyzed using mathematical formulas for the compressive strength of concrete bricks and water absorption capacity, compared with SNI 3-0349-1989 for solid concrete bricks, and analyzed comparatively. Based on the test results in this research laboratory, it is concluded that a balanced composition to get good quality is found in 70% sagu fiber and 30% sand.

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Zhang, Liwen, Zuqian Jiang, Hui Wu, Wenhua Zhang, Yushan Lai, Weile Zheng, and Jing Li. "Flexural Properties of Renewable Coir Fiber Reinforced Magnesium Phosphate Cement, Considering Fiber Length." Materials 13, no. 17 (August 20, 2020): 3692. http://dx.doi.org/10.3390/ma13173692.

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Coir fiber (CF), a renewable natural plant fiber, is more competitive in improving poor toughness and crack resistance of magnesium phosphate cement (MPC) than artificial fibers, due to its slight energy consumptions and low costs in production and waste treatment. In this paper, a typical three-point bending test was carried out to study the effects of CF length on MPC flexural properties. A total of forty-two cuboid specimens were employed to investigate the flexural strength, load-deflection behavior, and flexural toughness of MPC, with CF lengths varying from 0 to 30 mm at the curing age of 7 days and 28 days. Results showed that, at both two curing ages, MPC flexural strength first increased with CF length increasing, and then deceased when CF length exceeded the threshold. However, with the increase of CF length, MPC flexural toughness increased continuously, while MPC elastic modulus displayed a decreasing trend. Additionally, Modern micro testing techniques, such as scanning electron microscope (SEM) and X-ray diffraction (XRD), were also used to study the microstructure and phase compositions of specimens for further explaining the themicroscopic mechanism.

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Ferreira Filho, A., C. Herrera, Nelson Batista de Lima, R. L. Plaut, and Angelo Fernando Padilha. "Texture Evolution of Ferritic (AlSl 430) Stainless Steel Strips during Cold Rolling, Annealing and Drawing." Materials Science Forum 539-543 (March 2007): 4926–31. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.4926.

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The evolution of the crystallographic texture of ferritic stainless steels, starting from the as received (hot rolled) condition from the steel mill, going through cold rolling, annealing and final stamping is analyzed in this paper. Two ferritic stainless steels (Nb stabilized) having a thickness of 3.0 and 0.7mm, have been employed. The thicker one has been cold rolled to 40 and 73% thickness reduction, annealed at 750 and 850°C for 1 hour. The thinner one, with a similar composition, has been 77% cold rolled and annealed at 870°C at the steel plant and subsequently submitted to deep drawing in order to evaluate texture and drawability. Texture has been evaluated using DRX in the as received, cold rolled, annealed and after drawing conditions. Drawability has been evaluated using tensile testing in order to obtain the FLC curves. AISI 430 stainless steel, in the as received condition presented a strong {100} texture in the <110> and <120> directions and the gamma fiber. After cold rolling, the material presented stronger gamma and weaker alpha fibers. Annealing of the cold rolled samples conduced to the vanishing of the alpha and strengthening of the gamma fiber, adequate for deep drawing operations. In spite of the AISI 430 of 0.7mm having presented a strong gamma fiber, other deep drawing properties were not adequate and the material cracked during stamping.

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Sukudom, Nawapon, and Lerpong Jarupan. "Characteristics and Properties of Reinforced Oil Palm Frond Fibers (OPFF) in Polyvinyl Alcohol (PVA) Composite for Tubular-Shaped Trays." Applied Mechanics and Materials 751 (April 2015): 3–8. http://dx.doi.org/10.4028/www.scientific.net/amm.751.3.

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Effects on characteristics and mechanical properties of oil palm frond fiber (OPFF) as a reinforced element in poly vinyl alcohol (PVA) were investigated in this study. Series of different loading of OPFF were prepared by the following compositions: 5, 10, 15, 20 and 25 part per resin (phr). Glycerol at 35 phr was also compounded using twin-screw extruder to decrease degree of crystallinity and to reduce shear force of PVA to improve the processability. Injection molding was used to produce specimen for testing. The results indicated that the OPFF has an impact on mechanical properties of the composite material. Different scanning calorimeter (DSC) showed that the melting temperature (Tm) of OPFF reinforced PVA blended with glycerol was shifted to having decrease when compared to the pure PVA. Different loading contents of OPFF indicated that the compressive strength and morphological properties performed by a similar fashion. A highest compressive strength and the modulus of OPFF-reinforced PVA at 25 phr were achieved. Scanning electron microscope (SEM) indicated that OPFF-reinforced PVA at 25 phr yielded no accumulation of OPFF fibers but showed the dispersion in the matrix phase. In conclusion, the OPFF derived from oil palm industry can be used as reinforcement for manufacturing of plant pot in the future stage

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Sokolovic, Dunja, Milica Hadnadjev-Kostic, Arpad Kiralj, and Radmila Secerov-Sokolovic. "Prediction of oily water separation efficiency by fiber beds using a new filter media property." Chemical Industry 72, no. 5 (2018): 253–64. http://dx.doi.org/10.2298/hemind180327017s.

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Bed coalescers are compact, easy to install, automate, and maintain with the ability to achieve high separation efficiencies. They have been increasingly applied in the industry even though their design often requires pilot plant experiments. In this paper, a new wetting property of polymer fibers regarding polar mineral oils was established. This property can be important for selection of filter media for liquid-liquid separation in many industrial applications. Medical oil was selected as the new reference liquid that does not wet the investigated polymers. The lipophilic/lyophobic ratio (LLR) reached values ranging from 3.28 to 18.81 and increased with the increase of the mineral oil polarity measured by the oil neutralization number. The LLR values were in an excellent agreement with the results obtained from the separation efficiency of a steady-state bed coalescer. Thus, simple, fast and inexpensive experiments can replace pilot plant or at least laboratory testing aiming at selecting a polymer for oil separation from wastewater.

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Lazarus, S. Benjamin, E. Jamuna, Sivam Duraisivam, and M. Ravisankar. "Experimental Investigation and Analysis of Ecofriendly Compression Molded Woven Plant Fibre Polyester Composite." Applied Mechanics and Materials 867 (July 2017): 48–57. http://dx.doi.org/10.4028/www.scientific.net/amm.867.48.

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Polymer matrix composites are widely applied for the manufacturing of components employed in hostile environments to increase the service life and sometimes at a later stage for the reclamation of worn out parts. Every decade, numerous materials and techniques are being introduced and developed for the effective protection of low cost bulk materials out of which the fabrication of components could be done. Among such techniques hand layup, matched die mould methods, contact mould methods, filament winding and pultrusion methods has being employed increasingly in the process industries which has several significant advantages over other processes. It has become a process of its reliability, better process control, ease of use, good surface finish and closeness of dimensions. One among the method matched die mould method was selected as the process of preparation of the composite plate in the presented work. However, there are some inherent problems with control of resin flow, application of high temperature for curing during fabrication process. To address those main problems, a systematic investigation was carried out. The selected material is natural plant fibre available in abundant called “Crotalaria juncea” and is being employed as a green manuring plant in agriculture. In the investigation, the fibre is taken in two different forms of random and woven orientations and plate fabrication is done with unsaturated polyester resin as the matrix. The investigation is on woven orientation of biaxial, biaxially stitched and unidirectional woven types were done using the fibre to the size of the plate to be fabricated. Woven fibres of these three types were done at fibre design centre, Kerala. It was found that the fabrication could be done by placing two layer and three layer of the woven mat alone. So for the three woven types, two layer and three layer plates were fabricated to give about six plates in total. Here again to arrive at a closeness value for each combination, three plates were fabricated and the average value is got by testing. Tensile, flexural, impact and shear testing was done on all the plates as per ASTM standards and the responses were noted and plots were drawn and studied for the orientation for which the material possessed best property. The second part of the study was, with the experimental results got from the woven orientation, analysis was done by ANSYS and LS-DYNA software for the mechanical property and the responses got, was matching with the experimental testing methods and found that both the results were nearly the same thereby optimizing the results achieved. This is presented in detail in the forth coming chapters. The studies revealed that the fibre parameters taken had a significant influence on the mechanical properties. It was found that at a particular weight fraction the mechanical properties achieved the highest values in case of random orientation and particular woven orientations in case woven types. The increase in layers also had an influence over the property of the material. This composite prepared also initiates us in preparing newer composites with existing natural fibers, which haven’t been yet explored and which can reduce the cost. This gives way also in preparation of the same and releasing a newer variety of material to the Engineering industry which can be suited for some required application.

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Li, Shan, Shumin Yang, Lili Shang, Xinge Liu, Jianfeng Ma, Qianli Ma, and Genlin Tian. "3D Visualization of Bamboo Node’s Vascular Bundle." Forests 12, no. 12 (December 17, 2021): 1799. http://dx.doi.org/10.3390/f12121799.

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The vascular bundle is an important structural unit that determines the growth and properties of bamboo. A high-resolution X-ray microtomography (μCT) was used to observe and reconstruct a three-dimensional (3D) morphometry model of the vascular bundle of the Qiongzhuea tumidinoda node due to its advantages of quick, nondestructive, and accurate testing of plant internal structure. The results showed that the morphology of vascular bundles varied significantly in the axial direction. In the cross-section, the number of axial vascular bundles reached a maximum at the lower end of the sheath scar, and the minimum of it was at the middle of the diaphragm. The frequency of axial vascular bundles decreased from the lower end of the node to the nodal ridge, and subsequently increased until the upper end of the bamboo node. The proportion of parenchyma, fibers, and conducting tissue was 65.7%, 30.5%, and 3.8%, respectively. The conducting tissues were intertwined to form a complex 3D network structure, with a connectivity of 94.77%. The conducting tissue with the largest volume accounted for 60.26% of the total volume of the conducting tissue. The 3D-distribution pattern of the conducting tissue of the node and that of the fibers were similar, but their thickness changed in the opposite pattern. This study revealed the 3D morphometry of the conducting tissue and fibers of the bamboo node, the reconstruction of the skeleton made the morphology more intuitive. Quantitative indicators such as the 3D volume, proportion, and connectivity of each type of tissue was obtained, the bamboo node was enlarged mainly caused by the particularly developed fibers. This work laid the foundation for a better understanding of the mechanical properties and water transportation of bamboo and revealed the mystery of bamboo node shedding of Q. tumidinoda.

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Villamil Watson, Daniel A., and David A. Schiraldi. "Biomolecules as Flame Retardant Additives for Polymers: A Review." Polymers 12, no. 4 (April 7, 2020): 849. http://dx.doi.org/10.3390/polym12040849.

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Biological molecules can be obtained from natural sources or from commercial waste streams and can serve as effective feedstocks for a wide range of polymer products. From foams to epoxies and composites to bulk plastics, biomolecules show processability, thermal stability, and mechanical adaptations to fulfill current material requirements. This paper summarizes the known bio-sourced (or bio-derived), environmentally safe, thermo-oxidative, and flame retardant (BEST-FR) additives from animal tissues, plant fibers, food waste, and other natural resources. The flammability, flame retardance, and—where available—effects on polymer matrix’s mechanical properties of these materials will be presented. Their method of incorporation into the matrix, and the matrices for which the BEST-FR should be applicable will also be made known if reported. Lastly, a review on terminology and testing methodology is provided with comments on future developments in the field.

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Asrat, Tesema Hailu, Rakesh Kumar Bachheti, Mesfin Getachew, and Limenew Abate. "Evaluation of pulp and paper making properties of Caesalpinia decapetela." Nordic Pulp & Paper Research Journal 37, no. 1 (November 4, 2021): 14–24. http://dx.doi.org/10.1515/npprj-2021-0001.

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Abstract The world demand for paper has been increased due to the increasing population Therefore, to cop up the limited wood fiber resources introducing raw material in pulp and paper industries is necessary. The aims of this study to evaluate the pulp and paper-making properties of Caesalpinia decapetela based on proximate chemical composition, fiber morphology, pulping, bleaching, and physical test of the final product. The results proximate chemical analysis showed that C. decapetela has holocellulose content of 78.14±0.1 % and lignin content 18.0±0.04 %. Fiber morphology revealed that the fibers were 0.708 mm long, 18.63 μm width, and have 5.1 μm cell wall thicknesses. Kraft pulping of C. decapetale, was performed at different active alkali (5 %, 10 %, 15 %, 20 % and 25 %) and temperature (150, 160 and 170 °C), keeping the sulphidity 25 % constant. The pulp maximum yield 44.1 % was obtained at active alkali content of 15 %, temperature 160 °C, and cooking time 90 minutes. The effect of pulping on fiber morphology was studied using scanning electron microscopy which showed the surface of fiber before pulping was tight, orderly arranged and the texture was relatively hard. After pulping, there was the removal of lignin, hemicellulose, and cellulose. Due to this fiber become soft loosened and contain micro-pores. Pulp produced was bleached, sheet preparation and testing were performed. The prepared paper sheets have a tensile index of 28.19 Nm/gm, burst index of 1.359 kPa m 2 / gm 1.359\hspace{0.1667em}\text{kPa}\hspace{0.1667em}{\text{m}^{2}}/\text{gm} , and tear indices of 4.2 mN m 2 / gm 4.2\hspace{0.1667em}\text{mN}\hspace{0.1667em}{\text{m}^{2}}/\text{gm} . This study concluded C. decapetale can be the new raw material for pulp and paper making industries. However, pilot plant studies are required to check this raw material for the full recommendation of the pulp and paper industries.

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Hu, Yue, Da Gang Li, Qiao Yun Deng, Yu Mei Wang, and Dong Liang Lin. "Novel Poly (vinyl Alcohol) Nanocomposites Reinforced with Nano Cellulose Fibrils Isolated from Plants by Mechanochemical Treatment." Applied Mechanics and Materials 174-177 (May 2012): 870–76. http://dx.doi.org/10.4028/www.scientific.net/amm.174-177.870.

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The objective of this study was to reinforce biodegradable polyvinyl alcohol (PVA) with nano cellulose fibrils generated from poplar and cotton through mechanochemical treatment. A method used a combination of acid and alkali treatment to obtain cellulose from poplar and cotton. The cellulose of both fibers was further processed by grinder treatment. PVA/nano cellulose composite was prepared successfully by an immersion method. The cellulose nanofibers and nanocomposite films were characterized with scanning electron microscope (SEM), tensile testing machine, ultraviolet-visible spectrophotometry (UV-vis). SEM showed the diameter of the cellulose was range between 30-100 nm and exhibited a high aspect ratio of over 1500. The mechanical properties of PVA were improved significantly and the two plant nanofibers had the similarly reinforcing effects in the matrix. Cellulose nanofibers as a future resource have tremendous potential since they are one of the most abundant organic resources on the earth.

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Kakade, Nirmala R., Vikas M. Jagdale, and Ganesh R. Jiwade. "PHYTOCHEMICAL SCREENING OF LEAVES, STEM AND FRUIT PARTS OF TRIBULUS TERRESTRIS." International Research Journal of Pharmacy 12, no. 2 (February 27, 2021): 19–22. http://dx.doi.org/10.7897/2230-8407.1202121.

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The comparative phytochemical analysis of leaves, stem and fruit powder of Tribulus terrestris was carried out by using preliminary phytochemical screening. To identify the phytochemical constituents, present in water and ethanol extracts of Tribulus terrestris leaves, stem and fruit, a preliminary analysis was done by using different testing methods of Frothing test, Mayer’s test, Hager’s test, Foam formation test, Lead acetate test, Molisch’s test and Ferric Chloride test. The phytochemical analysis study showed the presence of 3.903%, 1.725% and 2.259% terpenoids & phenolic in leaves, stem and fruit parts of Tribulus terrestris respectively. The study showed the presence of 16.574%, 15.943% and 10.168% alkaloids and 0.240%, 0.160% and 0.230% Q. alkaloid & N-oxides in leaves stem and fruit extracts respectively. 2.888%, 0.825% and 2.679% fats and waxes and 76.395%, 81.347% and 84.672% fibers were observed in leaves, stem and fruit extracts of this plant respectively

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Chen, Xinxin, Jiaao Yu, and Xiu-Hang Zhang. "640 Mussel-inspired Polydopamine-assisted Bromelain Immobilization onto Electrospun Fibrous Membrane for Potential Application as Wound Dressing." Journal of Burn Care & Research 41, Supplement_1 (March 2020): S165—S166. http://dx.doi.org/10.1093/jbcr/iraa024.261.

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Abstract Introduction Skin damage as a result of injury, be it acute or chronic, can adversely impact the quality of life of affected individuals, with serious wounds being life-threatening in certain cases, leading to a high clinical demand for effective wound dressing materials. Effective wound dressings are those which maintain moisture in the wound site, maintaining hemostasis while preventing the development of any infections, thereby allowing air and water to more effectively facilitate epithelization. At present the bioactivity of most wound dressings is relatively poor, with more effective dressings being very costly and difficult to produce, necessitating the development of novel wound healing materials. Recent research has highlighted the potential of electrospun fibrous membranes as a material for use in wound dressing design. Membranes designed using electrospinning technology have desirable features including a pore size that is readily tunable, as well as substantial air permeability and a high surface-to-volume ratio. These membranes also have a 3D structure that is similar to the structure of the extracellular matrix (ECM), which is essential for mediating effective cellular adhesion and proliferation. These advantageous properties make such electrospun fibers potentially ideal for use in wound dressings. Studies have further sought to functionalize these fibers so as to enhance their ability to promote wound healing via imbuing them with growth factors, antibacterial compounds, or other bioactive materials. Current ongoing efforts have to functionalize electrospun fibers offer great potential for efforts to regulate wound healing. Given their safety and relatively low cost, bioactive plant extracts have been the subject of particular interest in the context of wound healing. One such extract is bromelain, which is a crude extract isolated from the pineapple fruit that contains a number of therapeutically valuable proteolytic enzymes. Previous work has shown bromelain to be capable of mediating anti-inflammatory and anti-edematous properties in many contexts including sinusitis, thrombophlebitis, angina pectoris, bronchitis, surgical trauma, and pyelonephritis. Bromelain is also known to be capable of hydrolyzing devitalized tissues so as to enhance rates of wound healing. Efforts to maintain the stability of bromelain are essential for its therapeutic utilization, with previous groups having demonstrated that bromelain can be effectively incorporated into electrospun or other polymer matrices. For example, Bayat et al. were able to use a blending electrospinning process to generate chitosan nanofibers loaded with bromelain, while Korrapati et al. used coaxial electrospinning in order to incorporate bromelain into electrospun fibers. In addition to direct incorporation, bromelain can also be immobilized directly onto the surface of electrospun fibers, allowing for more direct interaction between bromelain and wound tissue. Unfortunately, electrospun fibers tend to interact poorly with enzymes, resulting in relatively poor enzymatic activity and stability. Therefore there is a need to develop better techniques for immobilizing bromelain onto electrospun fibers. Previous studies have highlighted the potential of mussel-inspired polydopamine (PDA), which is produced via oxidatively polymerizing dopamine, as a substrate with the potential for utilization in the development of advanced biomaterials. PDA is readily deposited onto a wide range of surfaces without the need of expensive or complex instruments and procedures in order to achieve this deposition. Importantly, PDA is highly versatile owing to the abundance of available functional groups, allowing it to be developed into a platform well-suited to use in myriad applications. PDA has been shown to ameliorate enzymatic immobilization via both Schiff base reactions and Michael-type addition. However, at present there are no reports regarding the potential for PDA to facilitate bromelain immobilization. In the present report we describe the successful use of PDA to mediate bromelain immobilization on electrospun fibers, with the resultant fibers being effective when used for dressing wounds. The synthetic polymer poly(e-caprolactone) (PCL), which exhibits good biocompatibility, was selected for use as a matrix that was used to generate a fibrous membrane onto which bromelain could be immobilized. The FDA has approved the biomedical use of PCL, and it has previously been shown to exhibit both a high degree of mechanical stability while also remaining biodegradable. In this report, we first immobilized bromelain onto electrospun PCL fibers via use of PDA and then explored the physical and chemical properties of the resultant membranes and of the bromelain deposited thereupon. We additionally assessed the utility of these membranes as mediators of cellular adhesion, cell proliferation, and antibacterial activity in vitro, and as drivers of enhanced wound healing in vivo. Together our findings highlight these bromelain-immobilized electrospun PCL fiber membranes as having great promise for use in wound healing applications. Methods PCL fiber were prepared via electrospinning, then bromelain-immobilized PCL fiber were generated. The surface morphology of fibers was obtained by scanning electron microscopy. Swelling test, water vapor transmission rates (WVTR), in vitro bromelain release and loading, enzyme activity and stability were tested to demonstrate the fiber scaffold characteristic. The prepared composite scaffolds had satisfactory antibacterial activity via Kirby–Bauer (K-B) disc method. The cell studies were performed to reveal that the scaffolds were biocompatible and safe for cell attachment. Histological and immunohistochemical examinations were performed in rats. In Vivo wound healing model were chosen to verify the PCL functionalization using PDA and bromelain can accelerate the wound healing process. Results We found that bromelain activity could be better stabilized when via its immobilization on electrospun fibers. The resultant BrPDA-PCL fibers exhibited promising properties including optimal mechanical stability, wettability, and rates of water vapor transmission. In addition, these BrPDA-PCL fibers were biocompatible, allowing for effective cellular adhesion and proliferation. The results of zone of inhibition testing further confirmed that these fibers achieved effective antibacterial activity against Escherichia coli and Staphylococcus aureus. When used in vivo, as compared with PCL fibers or control animals the BrPDA-PCL fibers enhanced wound healing rates while reducing associated inflammation. Conclusions Herein we found that using PDA to immobilize bromelain onto electrospun PCL fibers resulted in the production of membranes that were highly effective wound dressings. Bromelain activity was markedly stabilized via the immobilization process, and the resultant BrPDA-PCL fibers were capable of supporting both cellular adhesion and proliferation. Given the observed synergy between PDA and bromelain, these BrPDA-PCL fibers also exhibited antibacterial activity. When utilized in a rat model of wound healing, inflammation was reduced and healing rates were improved in rats treated using BrPDA-PCL fibers relative to untreated controls. We therefore propose that future studies further examine the value of bromelain-immobilized electrospun PCL fibers as a means of enhancing epithelial regeneration. Applicability of Research to Practice The electrospun BrPDA-PCL fibers were capable of loading and delivering drugs, and could be potentially used as novel antibacterial burn wound dressings. These scaffolds have promising potential applications in infection control at the early phase of burn injury and accelerate wound healing process.

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Log, Torgrim, and Amalie Gunnarshaug. "Analysis of a Costly Fiberglass-Polyester Air Filter Fire." Energies 15, no. 20 (October 19, 2022): 7719. http://dx.doi.org/10.3390/en15207719.

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In September 2020, a fire at a liquefied natural gas (LNG) plant in the Arctic areas of Norway received national attention. In an unengaged air intake, the heat exchanger designed to prevent ice damage during production mode, was supplied hot oil at 260 °C. In sunny weather, calm conditions, and 14 °C ambient temperature, overheating of the unengaged air intake filters (85% glass fiber and 15% polyester) was identified as a possible cause of ignition. Laboratory heating tests showed that the filter materials could, due to the rigid glass fibers carrying the polymers, glow like smoldering materials. Thus, self-heating as observed for cellulose-based materials was a possible ignition mechanism. Small-scale testing (10 cm × 10 cm and 8 cm stacked height) revealed that used filters with collected biomass, i.e., mainly pterygota, tended to self-heat at 20 °C lower temperatures than virgin filters. Used filter cassettes (60 cm by 60 cm and 50 cm bag depth) caused significant self-heating at 150 °C. At 160 °C, the self-heating took several hours before increased smoke production and sudden transition to flaming combustion. Since the engaged heat exchanger on a calm sunny day of ambient temperature 14 °C would result in temperatures in excess of 160 °C in an unengaged air intake, self-heating and transition to flaming combustion was identified as the most likely cause of the fire. Flames from the burning polymer filters resulted in heat exchanger collapse and subsequent hot oil release, significantly increasing the intensity and duration of the fire. Due to firewater damages, the plant was out of operation for more than 1.5 years. Better sharing of lessons learned may help prevent similar incidents in the future.

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Angelova, Galena, Mariya Brazkova, Petya Stefanova, Denica Blazheva, Veselin Vladev, Nadejda Petkova, Anton Slavov, et al. "Waste Rose Flower and Lavender Straw Biomass—An Innovative Lignocellulose Feedstock for Mycelium Bio-Materials Development Using Newly Isolated Ganoderma resinaceum GA1M." Journal of Fungi 7, no. 10 (October 15, 2021): 866. http://dx.doi.org/10.3390/jof7100866.

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In this study, for the first time, the potential of rose flowers and lavender straw waste biomass was studied as feeding lignocellulose substrates for the cultivation of newly isolated in Bulgaria Ganoderma resinaceum GA1M with the objective of obtaining mycelium-based bio-composites. The chemical characterization and Fourier Transform Infrared (FTIR) spectroscopy established that the proximate composition of steam distilled lavender straw (SDLS) and hexane extracted rose flowers (HERF) was a serious prerequisite supporting the self-growth of mycelium bio-materials with improved antibacterial and aromatic properties. The basic physico-mechanical properties of the developed bio-composites were determined. The apparent density of the mycelium HERF-based bio-composites (462 kg/m3) was higher than that of the SDLS-based bio-composite (347 kg/m3) and both were much denser than expanded polystyren (EPS), lighter than medium-density fiber board (MDF) and oriented strand board (OSB) and similar to hempcrete. The preliminary testing of their compressive behavior revealed that the compressive resistance of SDLS-based bio-composite was 718 kPa, while for HERF-based bio-composite it was 1029 kPa and both values are similar to the compressive strength of hempcrete with similar apparent density. Water absorbance analysis showed, that both mycelium HERF- and SDLS-based bio-composites were hydrophilic and further investigations are needed to limit the hydrophilicity of the lignocellulose fibers, to tune the density and to improve compressive resistance.

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Mariana Isir and Vera Iriani Abdullah. "Testing The Effectiveness of The Pregnancy of Centella Asiatica Leaf Extract Gel Formula 10% for Striae Gravidarum Management in Pregnant Women." EMBRIO 13, no. 2 (November 29, 2021): 125–33. http://dx.doi.org/10.36456/embrio.v13i2.4145.

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Referring to the Sustainable Development Goals, there are 4 pillars, which one of them is the realization of biodiversity through bioprospecting activities in the fulfillment of medicinal raw materials. Centella asiatica or daun pegagan is a plant with an aromatic smell and has many benefits. Centella asiatica contains collagen. The collagen has functions to tighten and elasticize the skin fibers so that it can overcome striae gravidarum. The purpose of this study was to analyze the effectiveness of the gel preparation of Centella asiatica. This gel was made by extracting the Centella asiatica leaves at 10% concentration for the treatment of striae gravidarum grade 1, 2 and 3 which examined before and after the intervention. The research method is quasi-experimental with a one group pretest-posttest design approach. The repondents are 3 pregnant women who had experiencing striae gravidarum grade 1, 2 and 3. This research was carried out at the Mariyat Health Center, Sorong Regency from June to August 2021. The research instrument use G.S.S. Atwal L.K (2006) method to assess the degree of striae gravidarum, paired T test for the analysis. The results of the research, gel preparation of Centella asiatica leaves extract formula (10%) is effective for treatment of striae gravidarum grade 1,2 and 3.

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Cardoso, Fernanda Brito, Carlos Henrique Queiroz Rego, Izabela Cristina de Oliveira, Alan Mario Zuffo, Ana Carina da Silva Cândido, and Charline Zaratin Alves. "Vigor testings for evaluating the physiological quality of chia seeds." Semina: Ciências Agrárias 40, no. 6Supl2 (September 30, 2019): 2891. http://dx.doi.org/10.5433/1679-0359.2019v40n6supl2p2891.

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Chia (Salvia hispanica L.) is a plant native to central and western Mexico and northern Guatemala belonging to the Lamiaceae family, well known for its seeds containing antioxidants, dietary fibers, and ?-linolenic acid, which helps to prevent different diseases, such as diabetes, obesity, cancer and Alzheimer. In Brazil, there is not much information about the crop, mainly about the physiological quality of its seeds. Therefore, the objective was to establish vigor testing methods to evaluate the physiological quality of chia seeds. Five seed lots were used, in which germination tests, seedling emergence, emergence velocity index and variations in the electrical conductivity test were carried out. The volume of distilled water was 25 and 50 mL, the number of seeds was 50 and 100, the temperature was 20, 25 and 30 °C, the soaking period was 1, 2, 4, 6, 12, 18 and 24 hours and variations in there was accelerated aging test by the traditional method and saturated NaCl solution, being periods of aging as 24, 48, 72 and 96 hours and temperatures of 38, 41 and 44 °C. It is concluded that both the electrical conductivity test and the accelerated aging test are efficient in evaluating the physiological quality of chia seeds. The electrical conductivity test must be performed with 100 seeds in 50 mL of distilled water, for four hours soaking at 25 or 30 °C; and the accelerated aging test should be performed at 44 °C for 24 hours by the traditional method or 41 °C for 24 hours using saturated NaCl solution.

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Tausif, Muhammad, Brian Duffy, Sergei Grishanov, Hamish Carr, and Stephen J. Russell. "Three-Dimensional Fiber Segment Orientation Distribution Using X-Ray Microtomography." Microscopy and Microanalysis 20, no. 4 (May 1, 2014): 1294–303. http://dx.doi.org/10.1017/s1431927614000695.

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AbstractThe orientation of fibers in assemblies such as nonwovens has a major influence on the anisotropy of properties of the bulk structure and is strongly influenced by the processes used to manufacture the fabric. To build a detailed understanding of a fabric’s geometry and architecture it is important that fiber orientation in three dimensions is evaluated since out-of-plane orientations may also contribute to the physical properties of the fabric. In this study, a technique for measuring fiber segment orientation as proposed by Eberhardt and Clarke is implemented and experimentally studied based on analysis of X-ray computed microtomographic data. Fiber segment orientation distributions were extracted from volumetric X-ray microtomography data sets of hydroentangled nonwoven fabrics manufactured from parallel-laid, cross-laid, and air-laid webs. Spherical coordinates represented the orientation of individual fibers. Physical testing of the samples by means of zero-span tensile testing and z-directional tensile testing was employed to compare with the computed results.

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Barragan Echenique, Diego M., Martine T. Dolan, Jason L. Koh, Benjamin A. Goldberg, and Farid Amirouche. "Infraspinatus Muscle Fiber Moment Arms During Abduction: A Biomechanical Comparison of Values for Intact Rotator Cuff, Supraspinatus Tear, Superior Capsular Reconstruction, and Reverse Total Shoulder Arthroplasty." Orthopaedic Journal of Sports Medicine 10, no. 5 (May 1, 2022): 232596712210983. http://dx.doi.org/10.1177/23259671221098378.

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Background: Lines of action of the superior, middle, and inferior infraspinatus muscle fibers work together to produce moment arms that change throughout abduction in an intact shoulder, after a supraspinatus tear, and after superior capsular reconstruction (SCR) and reverse total shoulder arthroplasty (rTSA). Purpose: To use moment arm values to indicate the efficacy of SCR and rTSA to restore infraspinatus function during shoulder abduction. Study Design: Descriptive laboratory study. Methods: A total of 5 human cadaveric shoulders placed in a testing apparatus were each actively abducted (0°-90°) under the following 4 conditions: intact, complete supraspinatus tear, SCR, and rTSA. The 3-dimensional coordinates of points were tracked along the origin and insertion of the superior, middle, and inferior infraspinatus fibers during abduction. Moment arm values were calculated using the origin-insertion method to determine abduction contribution of infraspinatus fiber sections. Analysis of variance and post hoc Tukey testing were used to compare differences in moment arms between the 4 conditions and between fiber sections. Results: In the intact condition, the superior infraspinatus fibers had an abduction moment that decreased with elevation until shifting to adduction. Conversely, the middle and inferior fibers had an adduction moment that turned to abduction (mean moment arm values from 0° to 90°: inferior, from –5.9 to 19.4 mm; middle, from –4.7 to 15.9 mm; superior, from 5.6 to –5.1 mm; P < .05). After a supraspinatus tear, superior fibers lacked any torque, and inferior and middle fibers lost adduction potential (inferior, from 4.8 to 14.0 mm; middle, from –0.2 to 9.6 mm; superior, from 1.0 to 0.7 mm; P < .05). SCR restored the initial superior fiber abduction moment (5.6 mm at 0°; P < .05); middle and inferior fibers had some restoration but were weaker than intact fibers. Loss of abduction moment in all fibers was seen with rTSA (inferior, from –9.6 to –1.6 mm; middle, from –10.5 to –3.6 mm; superior, from –1.7 to –4.6 mm; P < .05). Conclusion: Infraspinatus fiber groups had different and inverse moment arms during scapular plane elevation. SCR most closely resembled the intact shoulder, whereas rTSA transformed the infraspinatus into an adductor. Clinical Relevance: These results support the efficacy of SCR at restoring biomechanical muscle function and suggest that the changes in moment arms for each fiber group be considered when choosing treatment modalities and rehabilitation protocols after rotator cuff tear.

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44

Sacks, M. S., M. C. Jimenez Hamann, S. E. Otan˜no-Lata, and T. I. Malinin. "Local Mechanical Anisotropy in Human Cranial Dura Mater Allografts." Journal of Biomechanical Engineering 120, no. 4 (August 1, 1998): 541–44. http://dx.doi.org/10.1115/1.2798027.

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Human cranial dura mater (CDM) allograft’s success as a repair biomaterial is partly due to its high mechanical strength, which facilitates its ability to form water-tight barriers and resist high in-vivo mechanical loads. Previous studies on CDM allograft mechanical behavior used large test specimens and concluded that the allograft was mechanically isotropic. However, we have quantified CDM microstructure using small angle light scattering (SALS) and found regions of well-aligned fibers displaying structural symmetry between the right and left halves (Jimenez et al., 1998). The high degree of fiber alignment in these regions suggests that they are mechanically anisotropic. However, identification of these regions using SALS requires irreversible tissue dehydration, which may affect mechanical properties. Instead, we utilized CDM structural symmetry to estimate the fiber architecture of one half of the CDM using computer graphics to flip the SALS fiber architecture map of the corresponding half about the plane of symmetry. Test specimens (20 mm × 4 mm) were selected parallel and perpendicular to the preferred fiber directions and subjected to uniaxial mechanical failure testing. CDM allografts were found to be locally anisotropic, having an ultimate tensile strength (UTS) parallel to the fibers of 12.76 ± 1.65 MPa, and perpendicular to the fibers of 5.21 ± 1.01 MPa (mean ± sem). These results indicate that uniaxial mechanical tests on large samples used in previous studies tended to mask the local anisotropic nature of the smaller constituent sections. The testing methods established in this study can be used in the evaluation of new CDM processing methods and post-implant allograft mechanical integrity.

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45

Lee, J. H., and J. H. Vogel. "An Investigation of the Formability of Long Fiber Thermoplastic Composite Sheets." Journal of Engineering Materials and Technology 117, no. 1 (January 1, 1995): 127–32. http://dx.doi.org/10.1115/1.2804363.

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An experimental and analytical investigation was undertaken to improve understanding of the form of long fiber reinforced thermoplastic sheets. The materials tested contained 30 percent by weight of glass fibers in a polypropylene matrix, with the fibers approximately randomly oriented in the plane of sheet. The forming tests covered a range of forming temperatures between the glass transition temperature and the melting point of the polypropylene matrix. The testing geometry was that of a Swift flat-bottomed cup test, which primarily tests bending and drawing behavior of the sheet. An analysis of the process was developed in terms of a continuum model of material behavior with normal anisotropy and rotational symmetry. Results of the forming tests are compared with analytical predictions. Limitations of both the form of the material and the modeling approach are discussed.

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46

Al Toubat, Salah, Hussein Ousman, Samer Barakat, and Klaus Alexander Rieder. "Viability of Synthetic Fibers to Replace Steel Wire Mesh in Composite Metal Decks Construction." Key Engineering Materials 471-472 (February 2011): 552–57. http://dx.doi.org/10.4028/www.scientific.net/kem.471-472.552.

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Composite metal decking has become one of the prevalent forms of Fast Track Construction for multi-story steel buildings. The in-plane stiffness of composite metal decks however is of considerable importance as they typically act as a diaphragm in lateral-load- resisting systems and thus attract a large in-plane shear. The diaphragm action or the in-plane shear capacity of composite metal decks remained a concern for structural engineers and designers. The present work aims to investigate the in-plane shear behavior of fiber reinforced composite metal decks and compare it to that reinforced with welded wire mesh. A comprehensive experimental program involving testing large scale slabs was conducted. Steel decking of trapezoidal profile with a sheet thickness of 0.9 mm was used to construct the composite slabs. Conventional WWF mesh reinforcement and synthetic macro fibers at different reinforcing rates were considered in the test program. The slabs were tested under monotonically increasing in-plane shear force until failure. Load-deflection responses were plotted and cracking pattern and sequence were recorded. The test results show that fibers provide comparable deck behavior as that with steel mesh. Both imparted similar ultimate in-plane shear capacity and enhanced the ductility and the post peak behavior of the composite metal decks relative to the control slab. The results demonstrate the viability of synthetic macro fibers to replace the steel mesh in this type of composite flooring systems.

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47

Little, Jesse S., and Partap S. Khalsa. "Material Properties of the Human Lumbar Facet Joint Capsule." Journal of Biomechanical Engineering 127, no. 1 (February 1, 2005): 15–24. http://dx.doi.org/10.1115/1.1835348.

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The human facet joint capsule is one of the structures in the lumbar spine that constrains motions of vertebrae during global spine loading (e.g., physiological flexion). Computational models of the spine have not been able to include accurate nonlinear and viscoelastic material properties, as they have not previously been measured. Capsules were tested using a uniaxial ramp-hold protocol or a haversine displacement protocol using a commercially available materials testing device. Plane strain was measured optically. Capsules were tested both parallel and perpendicular to the dominant orientation of the collagen fibers in the capsules. Viscoelastic material properties were determined. Parallel to the dominant orientation of the collagen fibers, the complex modulus of elasticity was E*=1.63MPa, with a storage modulus of E′=1.25MPa and a loss modulus of: E″=0.39MPa. The mean stress relaxation rates for static and dynamic loading were best fit with first-order polynomials: Bε=0.1110ε−0.0733 and Bε=−0.1249ε+0.0190, respectively. Perpendicular to the collagen fiber orientation, the viscous and elastic secant moduli were 1.81 and 1.00 MPa, respectively. The mean stress relaxation rate for static loading was best fit with a first-order polynomial: Bε=−0.04ε−0.06. Capsule strength parallel and perpendicular to collagen fiber orientation was 1.90 and 0.95 MPa, respectively, and extensibility was 0.65 and 0.60, respectively. Poisson’s ratio parallel and perpendicular to fiber orientation was 0.299 and 0.488, respectively. The elasticity moduli were nonlinear and anisotropic, and capsule strength was larger aligned parallel to the collagen fibers. The phase lag between stress and strain increased with haversine frequency, but the storage modulus remained large relative to the complex modulus. The stress relaxation rate was strain dependent parallel to the collagen fibers, but was strain independent perpendicularly.

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Tobata, Yuta, Shinsuke Takeuchi, and Ken Goto. "Cumulative Shear Damage Mechanism to Short Fiber Type C/SiC." Journal of Composites Science 5, no. 9 (August 30, 2021): 230. http://dx.doi.org/10.3390/jcs5090230.

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A cumulative damage mechanism for short fiber type C/SiC during shear loading–unloading testing was examined and quantified using Iosipescu specimens parallel in the in-plane and through-thickness plane, and by using modified fracture and damage mechanics theory referring to measured damage characteristics (crack length, number and angle). A nonlinear stress–strain relation was found for both specimens. Decrease in the apparent modulus was confirmed with increased peak stress, although permanent strain increased. Inelastic strain of the decomposed tensile direction derived from shear stress was greater than that of the compressive one. Cracks propagated perpendicularly to the tensile direction, intruding on the boundary of the transverse fibers and connecting to other cracks. The theoretical damage mechanics model succeeded to predict the stress–strain relation, proposing that the shear mechanical properties are predictable by measuring the damage characteristics.

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49

Velho, Helder Callegaro, Paolo Baldissara, Jovito Adiel Skupien, and Vinicius Felipe Wandscher. "Fracture load and shear stress of prefabricated glass fiber posts." Brazilian Journal of Oral Sciences 18 (November 18, 2019): e191561. http://dx.doi.org/10.20396/bjos.v18i0.8657253.

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Aim: This study evaluated the fracture load and pattern failure of different prefabricated glass fiber posts (GFPs) of the same diameter. Methods: Seventy-eight (n=13 for six groups) GFPs of 1.6 mm coronal diameter of different brands were evaluated— Exacto (Angelus), Power Post (BM4), White Post DC (FGM), HiRem (Overfibers), MAQ (Maquira), and SD (Supordont). The posts were subjected to fracture load testing (45° of inclination and 1 mm/min until fracture). Each factor (load (N) and shear stress (MPa)) was analyzed separately using one-way ANOVA followed by the Tukey test (α=0.05). Results: The type of failure was evaluated on a stereomicroscope (×10). The Power Post samples presented higher values of fracture load (p<0.001) followed by Maquira fiber post, White Post , HiRem, Superpost, and the Exacto posts. The failure pattern observed was intralaminar mode II in-plane shear, such as a failure occur parallel to fibers. Conclusion: Despite the same diameter of GFPs, the fracture load and shear resistance were brand-dependent.

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Ataya, Sabbah, Mohamed M. El-Sayed Seleman, Fahamsyah H. Latief, Mohamed M. Z. Ahmed, Khalil Hajlaoui, Ahmed M. Soliman, Naser A. Alsaleh, and Mohamed I. A. Habba. "Wear Characteristics of Mg Alloy AZ91 Reinforced with Oriented Short Carbon Fibers." Materials 15, no. 14 (July 12, 2022): 4841. http://dx.doi.org/10.3390/ma15144841.

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Light-weight metal matrix composites, especially magnesium-based composites, have recently become more widespread for high-efficiency applications, including aerospace, automobile, defense, and telecommunication industries. The squeeze cast AZ91 base material (AZ91-BM) and its composites having 23 vol.% short carbon fibers were fabricated and investigated. The composite specimens were machined normal to the reinforced plane (Composite-N) and parallel to the reinforced plane (Composite-P). All the as-casted materials were subjected to different tests, such as hardness, compression, and wear testing, evaluating the mechanical properties. Dry wear tests were performed using a pin-on-disk machine at room temperature under different applied wear loads (1–5 N) and different sliding distances (0.4461×104–3.12×104 m). The microstructures and worn surfaces of the fabricated AZ91-BM and the two composite specimens were investigated using a scanning electron microscope (SEM) equipped with an energy dispersive spectroscopy (EDS) advanced analysis system. The wear debris was collected and investigated also under the SEM. The results showed significant improvement in hardness, compressive strength, and wear resistance of the composite specimens (Composite-N and Composite-P) over the AZ91-BM. The compressive strength and wear resistance are more fibers orientation sensitive than the hardness results. When the fiber orientation is parallel to the sliding direction (Composite-N), the weight loss is somewhat lower than that of the fiber orientation perpendicular to the sliding direction (Composite-P) at a constant wear load of 2 N and the sliding distances of 0.4461×104, 1.34×104 , and 2.23×104 m. In contrast, the weight loss of Composite-P is lower than Composite-N, especially at the highest sliding distance of 3.12×104 m due to the continuous feeding of graphite lubricant film and the higher compressive strength. Plastic deformation, oxidation, and abrasive wear are the dominant wear mechanisms of AZ91-BM; in contrast, abrasive and delamination wear are mainly the wear mechanisms of the two composites under the applied testing conditions.

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