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1
Angel, Allen, and Kathryn A. Jakes. "Preparation And elemental analysis of ancient fibers." Proceedings, annual meeting, Electron Microscopy Society of America 45 (August 1987): 410–11. http://dx.doi.org/10.1017/s0424820100126846.
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Fabrics recovered from archaeological sites often are so badly degraded that fiber identification based on physical morphology is difficult. Although diagenetic changes may be viewed as destructive to factors necessary for the discernment of fiber information, changes occurring during any stage of a fiber's lifetime leave a record within the fiber's chemical and physical structure. These alterations may offer valuable clues to understanding the conditions of the fiber's growth, fiber preparation and fabric processing technology and conditions of burial or long term storage (1).Energy dispersive spectrometry has been reported to be suitable for determination of mordant treatment on historic fibers (2,3) and has been used to characterize metal wrapping of combination yarns (4,5). In this study, a technique is developed which provides fractured cross sections of fibers for x-ray analysis and elemental mapping. In addition, backscattered electron imaging (BSI) and energy dispersive x-ray microanalysis (EDS) are utilized to correlate elements to their distribution in fibers.
2
Mcguigan, Michael R. M., William J. Kraemer, Michael R. Deschenes, Scott E. Gordon, Takashi Kitaura, Timothy P. Scheett, Matthew J. Sharman, and Robert S. Staron. "Statistical Analysis of Fiber Area in Human Skeletal Muscle." Canadian Journal of Applied Physiology 27, no. 4 (August 1, 2002): 415–22. http://dx.doi.org/10.1139/h02-022.
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Previous research has indicated that 50 fiber measurements per individual for type I and II fibers would be sufficient to characterize the fiber areas. This study replicated the work of McCall et al. (1998) using the three major fiber types (I, IIA, and IIB) and sampling larger populations of fibers. Random blocks of fibers were also examined to investigate how well they correlated with the overall mean average fiber area. Using random blocks of 50 fibers provided an accurate reflection of the type IIB fibers (r = 0.96-0.98) but not for the type I (r = 0.85-0.94) or IIA fibers (r = 0.80-0.91). Type I fibers were consistently reflected by a random block of 150 fibers (r = 0.95-0.98) while type IIA fibers required random blocks of 200 fibers (r = 0.94-0.98), which appeared to provide an accurate reflection of the cross-sectional area. These results indicate that for a needle biopsy different numbers of fibers are needed depending on the fiber type to accurately characterize the mean fiber population. Key words: fiber type, sample size, cross-sectional area, biopsy
3
Zhou, Rong, and Ming Xia Yang. "Research on Mechanical Properties of Several New Regenerated Cellulose Fibers." Advanced Materials Research 332-334 (September 2011): 489–95. http://dx.doi.org/10.4028/www.scientific.net/amr.332-334.489.
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Regenerated cellulose fiber is the most widely-used and most variety of cellulose fiber. Five categories and ten kinds of fibers such as lyocell fiber, modal fiber, bamboo pulp fiber, sheng-bast fiber, Outlast viscose fiber were chosen as the research object. The strength property and elasticity of fibers in dry and wet state were tested and analysis. The comprehensive performances of fabrics were studied and mechanical properties of the fibers were listed in the order from good to bad by grey clustering analysis. The results show lyocell G100 and lyocell LF have better comprehensive mechanical properties ,while other new regenerated cellulose fibers’ comprehensive mechanical properties are general. Among these fibers modal fiber’s comprehensive mechanical properties are slightly better than sheng-bast fibers’ and bamboo pulp fibers’. Modal fiber, sheng-bast fiber and Bamboo pulp fiber have no significantly poor single parameter and all of them have better comprehensive mechanical properties than various viscose fibers. Outlast viscose in which has been added phase change materials sensitive to temperature by Microcapsule techniques fundamentally keeps similar comprehensive mechanical properties with other regenerated cellulose fibers,but its properties decline slightly .
4
Cho, Liling, and David L. Wetzel. "Polarized microbeam FT-IR analysis of single fibers." Proceedings, annual meeting, Electron Microscopy Society of America 54 (August 11, 1996): 206–7. http://dx.doi.org/10.1017/s0424820100163496.
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Polarized infrared microscopy has been used for forensic purposes to differentiate among polymer fibers. Dichroism can be used to compare and discriminate between different polyester fibers, including those composed of polyethylene terephthalate that are frequently encountered during criminal casework. In the fiber manufacturering process, fibers are drawn to develop molecular orientation and crystallinity. Macromolecular chains are oriented with respect to the long axis of the fiber. It is desirable to determine the relationship between the molecular orientation and stretching properties. This is particularly useful on a single fiber basis. Polarized spectroscopic differences observed from a single fiber are proposed to reveal the extent of molecular orientation within that single fiber. In the work presented, we compared the dichroic ratio between unstretched and stretched polyester fibers, and the transition point between the two forms of the same fiber. These techniques were applied to different polyester fibers. A fiber stretching device was fabricated for use on the instrument (IRμs, Spectra-Tech) stage. Tension was applied with a micrometer screw until a “neck” was produced in the stretched fiber. Spectra were obtained from an area of 24×48 μm. A wire-grid polarizer was used between the source and the sample.
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Liu, Ling Yun, Chuan Qi Xu, Yu Qing Liu, and W. Pajeshwatt. "Preparetion and Quantitative Analysis of Programmable Polyester Fiber." Materials Science Forum 1001 (July 2020): 202–6. http://dx.doi.org/10.4028/www.scientific.net/msf.1001.202.
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At present, the anti-counterfeiting fibers are mainly monochromatic fluorescent fibers, dual-band fluorescent fibers, and multicolor segment dyed fibers. However, anti-counterfeiting fibers using only these several anti-counterfeiting methods are increasingly unable to meet the needs of anti-counterfeiting technology for high efficiency, greenness, and security. This paper studies the method of setting passwords using multi-bit sequence programming in the spinning process, and enables passwords to be effectively stored throughout the fiber production and sales chain. Because nanoscale metal inorganic salts and metal oxide powders have good dispersion, they can be well and uniformly dispersed in the spinning solution. In addition, metal elements can be relatively stable in the spinning process, providing the possibility of traceability of programmable passwords. Setting a password in this method can effectively improve the anti-counterfeiting performance of the fiber without affecting the basic properties of the fiber, and will help to develop new technology for tracking and identifying anti-counterfeit fibers.
6
Cai, Yiyun, Abdelfattah Mohamed Seyam, and Yong K. Kim. "Formation of Fiberwebs from Staple Fibers with Controlled Fiber Orientation Using Electrostatic Forces: Theoretical Analysis." Journal of Engineered Fibers and Fabrics 2, no. 2 (June 2007): 155892500700200. http://dx.doi.org/10.1177/155892500700200202.
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Current web formation technologies used by the nonwovens industry do not provide positive control over fiber orientation and it is difficult to generate lightweight webs from staple fibers with these processes. The aim of this research is to develop new methods of fiberweb formation using electrostatic force, where orientation and orientation distribution of staple fibers are positively controlled. We carried out theoretical analysis and constructed computer models for this approach. Our analysis considered the effects of geometric configurations of fiber feeding and web formation zone, electrostatic and airflow field parameters, and the fiber's initial conditions at the feeding zone on fiber orientation. The theoretical analyses and computer modeling of the electrostatic web forming process provide better insights into this method and serve as a powerful tool for engineering development. Numerical results were obtained and presented for a range of processing variables.
7
Bluemke, David A., Bridget Carragher, Barbara Gabriel, Michael J. Potel, and Robert Josephs. "Structural analysis of sickle hemoglobin fibers." Proceedings, annual meeting, Electron Microscopy Society of America 45 (August 1987): 742–43. http://dx.doi.org/10.1017/s042482010012802x.
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We have used helical reconstruction and electron density modeling techniques in our analysis of the structure of sickle hemoglobin (HbS) fibers. The formation of HbS fibers in red blood cells under conditions of deoxygenation is responsible for the clinical manifestations of sickle cell disease. Fibers have a helical pitch of about 2700 Å and an average diameter of about 210 Å. The subunit of structure in fibers consists of two half-staggered strands of HbS molecules termed double strands. Double strands in fibers are oriented such that the axis of the constituent double strands is nearly parallel to the particle axis, as indicated by the optical diffraction pattern of these particles.The pitch of fibers varies from particle to particle, as well as within a single fiber, and this presents special problems in the structural analysis. We have measured the distances corresponding to 180° of rotation in 245 fibers.
8
Tungol, Mary W., Edward G. Bartick, and Akbar Montaser. "Forensic Analysis of Acrylic Copolymer Fibers by Infrared Microscopy." Applied Spectroscopy 47, no. 10 (October 1993): 1655–58. http://dx.doi.org/10.1366/0003702934334552.
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Ratios of absorbance peak areas ( AC=O/ AC=N) of carbonyl and nitrile groups were obtained for single acrylic fibers by IR microscopy. The precision of the comonomer ratios was evaluated for potential application in forensic fiber examinations. Precise (RSDs less than 0.4%) results for repetitive analyses of one location on a fiber were obtained. Precision was reduced when the cited ratio was measured at adjacent locations along the length of a single fiber. A further deterioration in precision was observed when different fiber specimens of the same type were analyzed. Analysis of different acrylic fiber specimens of the same type yielded RSDs which ranged from 2 to 6%. Fibers with diameters which ranged from 13 to 43 µm were examined. Precision was decreased for fibers with smaller diameters. Preliminary results indicate that acrylic fibers can differ by manufacturer as indicated by AC=O/ AC=N.
9
Hanamori, T., K. Hirota, and N. Ishiko. "Receptive fields and gustatory responsiveness of frog glossopharyngeal nerve. A single fiber analysis." Journal of General Physiology 95, no. 6 (June 1, 1990): 1159–82. http://dx.doi.org/10.1085/jgp.95.6.1159.
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Receptive fields and responsiveness of single fibers of the glossopharyngeal (IXth) nerve were investigated using electrical, gustatory (NaCl, quinine HCl, acetic acid, water, sucrose, and CaCl2), thermal, and mechanical stimulation of the single fungiform papillae distributed on the dorsal tongue surface in frogs. 172 single fibers were isolated. 58% of these fibers (99/172) were responsive to at least one of the gustatory stimuli (taste fibers), and the remaining 42% (73/172) were responsive only to touch (touch fibers). The number of papillae innervated by a single fiber (receptive field) was between 1 and 17 for taste fibers and between 1 and 10 for touch fibers. The mean receptive field of taste fibers (X = 6.6, n = 99) was significantly larger than that of touch fibers (X = 3.6, n = 73) (two-tailed t test, P less than 0.001). In experiments with natural stimulation of single fungiform papillae, it was found that every branch of a single fiber has a similar responsiveness. Taste fibers were classified into 14 types (Type N, Q, A, NA, NCa, NCaA, NCaW, NCaAW, NCaWS, NQ, NQA, NQAS, NQWarm, Multiple) on the basis of their responses to gustatory and thermal stimuli. The time course of the response in taste fibers was found to be characteristic of their types. For example, the fibers belonging to Type NQA showed phasic responses, those in Type NCa showed tonic responses, etc. These results indicate that there are several groups of fibers in the frog IXth nerve and that every branch of an individual fiber has a similar responsiveness to the parent fiber.
10
Zhang, Haiwei, Peiwen Hao, Yuan Pang, and Aaron D. Mwanza. "Design Method and Cost-Benefit Analysis of Hybrid Fiber Used in Asphalt Concrete." Advances in Materials Science and Engineering 2016 (2016): 1–9. http://dx.doi.org/10.1155/2016/8014704.
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Fiber, as an additive, can improve the performance of asphalt concrete and be widely studied, but only a few works have been done for hybrid fiber. This paper presents a new and convenient method to design hybrid fiber and verifies hybrid fiber’s superiority in asphalt pavement engineering. Firstly, this paper expounds the design method used as its applied example with the hybrid fiber composed of lignin, polyester, and polypropylene fibers. In this method, a direct shear device (DSD) is used to measure the shear damage energy density (SDED) of hybrid fiber modified asphalts, and range and variance statistical analysis are applied to determine the composition proportion of hybrid fiber. Then, the engineering property of hybrid fiber reinforced asphalt concrete (AC-13) is investigated. Finally, a cost-benefit model is developed to analyze the advantage of hybrid fiber compared to single fibers. The results show that the design method employed in this paper can offer a beneficial reference. A combination of 1.8% of lignin fiber and 2.4% of polyester fiber plus 3.0% polypropylene fiber presented the best reinforcement of the hybrid fiber. The cost-benefit model verifies that the hybrid fiber can bring about comprehensive pavement performance and good economy.
11
Oliveira Glória, Gabriel, Giulio Rodrigues Altoé, Pedro Amoy Netto, Frederico Muylaert Margem, Fabio de Oliveira Braga, and Sergio Neves Monteiro. "Density Weibull Analysis of Pineapple Leaf Fibers (PALF) with Different Diameters." Materials Science Forum 869 (August 2016): 384–90. http://dx.doi.org/10.4028/www.scientific.net/msf.869.384.
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Societal, economical, technical and environmental advantages are today justifying the replacement of synthetic fibers by natural fibers. However, natural fibers obtained from plants do not present the same dimensional uniformity. In fact, they show large dispersion of values, as compared to synthetic fibers. In the case of the lignocellulosic fiber extracted from the pineapple leaf, limited information exists regarding the correlation between its properties and dimensional characteristics. In particular, so far, no investigation has been carried out on the influence of the diameter and the density of pineapple fibers. Therefore, the objective of this work was to measure the density of pineapple fibers and to define, by means of the Weibull statistic method, its dependence on the corresponding fiber diameter.
12
Gu, Hong Xing, Hao Jing Wang, and Li Dong Fan. "Structure Characterization and Property Analysis of HKT800 Carbon Fiber." Applied Mechanics and Materials 799-800 (October 2015): 183–86. http://dx.doi.org/10.4028/www.scientific.net/amm.799-800.183.
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The characterization and properties of the HKT800 carbon fiber were performed, and results showed that the tensile strength, tensile modulus and tensile elongation of HKT800 carbon fiber reached 5.6 GPa, 290 GPa and 1.9 %, respectively. The Cv value of all index was less than 3 %, and there were a few HKT800 carbon fibers belong to the cashew type. Furthermore, the surface activity of 6 K carbon fibers was higher than that of the 12 K carbon fibers after the same surface treatment. It was found that the sizing agent existed on the surface of HKT800 carbon fiber was epoxy resin.
13
Candido, Leandro, Francesco Micelli, Emilia Vasanelli, Maria Antonietta Aiello, and Giovanni A. Plizzari. "Cracking Analysis of FRC Beams under Sustained Long-Term Loading." Key Engineering Materials 711 (September 2016): 844–51. http://dx.doi.org/10.4028/www.scientific.net/kem.711.844.
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Crack formation within concrete members undergoing flexural loading is a complex mechanism, which governs the serviceability and durability of concrete structures. As for reinforced concrete (RC) members, a number of works based on empirical or theoretical approaches are published in the scientific literature. All the models propose a formulation for the estimation of crack spacing and crack width taking into account several parameters. Mechanical properties of concrete matrix, reinforcement ratio, concrete cover, bar diameter and size effect are the most influencing parameters on the cracking pattern of RC members, while tension stiffening can be influential as well. In Fiber Reinforced Concrete (FRC) elements the presence of short fibers modifies the crack pattern within the members due to the development of a residual tensile stress and greater toughness. Normally the number of cracks within the length of FRC members is higher while the mean crack spacing and the crack width are lower. In fact the crack bridging effect of fibers consists in post-cracking stresses between the crack faces. Such mechanism is mainly governed by the interface bond between fiber and concrete matrix. Therefore, the volume fraction and the geometrical properties of fibers strongly influence the overall contribution in the cracking phenomena. A limited number of design codes have taken into account the modified behaviour of FRC members (especially in the case of steel fibers) by providing specific equations for crack width. This work presents the results of an experimental campaign on RC beams subjected to sustained service loads and environmental exposure for 72 months. In some beams, short steel or polyester fibers were added to the concrete matrix. The results presented in the paper show that the addition of fibres in concrete reduces both flexural displacements and crack widths, by modifying also the long-term behaviour of FRC members.
14
Rhee, Hannah S., Catherine M. Steel, Frederik J. Derksen, N. Edward Robinson, and Joseph F. Y. Hoh. "Immunohistochemical Analysis of Laryngeal Muscles in Normal Horses and Horses With Subclinical Recurrent Laryngeal Neuropathy." Journal of Histochemistry & Cytochemistry 57, no. 8 (April 27, 2009): 787–800. http://dx.doi.org/10.1369/jhc.2009.953844.
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We used immunohistochemistry to examine myosin heavy-chain (MyHC)-based fiber-type profiles of the right and left cricoarytenoideus dorsalis (CAD) and arytenoideus transversus (TrA) muscles of six horses without laryngoscopic evidence of recurrent laryngeal neuropathy (RLN). Results showed that CAD and TrA muscles have the same slow, 2a, and 2x fibers as equine limb muscles, but not the faster contracting fibers expressing extraocular and 2B MyHCs found in laryngeal muscles of small mammals. Muscles from three horses showed fiber-type grouping bilaterally in the TrA muscles, but only in the left CAD. Fiber-type grouping suggests that denervation and reinnervation of fibers had occurred, and that these horses had subclinical RLN. There was a virtual elimination of 2x fibers in these muscles, accompanied by a significant increase in the percentage of 2a and slow fibers, and hypertrophy of these fiber types. The results suggest that multiple pathophysiological mechanisms are at work in early RLN, including selective denervation and reinnervation of 2x muscle fibers, corruption of neural impulse traffic that regulates 2x and slow muscle fiber types, and compensatory hypertrophy of remaining fibers. We conclude that horses afflicted with mild RLN are able to remain subclinical by compensatory hypertrophy of surviving muscle fibers.
15
Hejazi, Seyed Mahdi, Seyed Mahdi Abtahi, Mohammad Sheikhzadeh, and Amir Mostashfi. "Micromechanical analysis of loop-formed fiber-reinforced soil composite." Journal of Industrial Textiles 44, no. 3 (July 8, 2013): 418–33. http://dx.doi.org/10.1177/1528083713495251.
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In this research, loop-formed fiber is introduced as a novel reinforcement method of soil composites instead of using ordinary fibers. In order to investigate the materials' mechanical properties, the shear behavior of both fiber and looped-fiber-reinforced soil composites was analyzed by micromechanical method (finite element method) and a set of direct shear tests. The results indicate that the looped-fiber soil composite exhibits greater failure strain energy compared with fiber-reinforced soil composite at the same fiber orientation in the substrate. Furthermore, the proposed model demonstrated two major reinforcing components: “the fiber effect” and “the loop effect.” The latter effect is the key benefit and the main advantage of using looped fibers over ordinary fibers in soil reinforcement. Altogether, there is a close agreement between finite element method outputs and experimental results, suggestive of a novel technical textile material that could potentially be used in geotechnical engineering.
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Roggli, Victor L. "The So-called Short-Fiber Controversy: Literature Review and Critical Analysis." Archives of Pathology & Laboratory Medicine 139, no. 8 (August 1, 2015): 1052–57. http://dx.doi.org/10.5858/arpa.2014-0466-ra.
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Context Numerous articles in the scientific literature indicate that pathogenic fibers with respect to asbestos-related diseases are those that exceed 5 μm in length. Nonetheless, some authors have expressed concerns regarding pathogenicity of shorter fibers. Objective To review the scientific evidence regarding pathogenicity (or lack thereof) of fibers less than or equal to 5 μm in length, with particular attention to publications indicating that such fibers might be hazardous. Data Sources The scientific literature was reviewed for experimental animal studies and human studies that address the role of fiber size in causation of disease. Sources included original studies, as well as review articles related to the topic. Conclusions Experimental animal studies involving inhalation of fibers have demonstrated that fibers greater than 5 μm in length are associated with both pulmonary fibrosis (ie, asbestosis) and malignancies (carcinoma of the lung and mesothelioma). There is no convincing evidence for a pathogenic effect for fibers that are 5 μm or less in length. Fiber analyses of human lung tissue samples provide further support for pathogenicity of long fibers, particularly the more biopersistent amphibole fibers. Similar observations have been reported for nonasbestos mineral fibers. Concerns expressed by some authors (eg, the greater abundance of short fibers) do not alter these conclusions. Similarly, in vitro studies demonstrating biological activity of short fibers do not override inhalational studies of whole animals or the epidemiological findings in humans.
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Monteiro, Sergio Neves, Frederico Muylaert Margem, Jean Igor Margem, Lucas Barbosa de Souza Martins, Caroline Gonçalves Oliveira, and Michel Picanço Oliveira. "Infra-Red Spectroscopy Analysis of Malva Fibers." Materials Science Forum 775-776 (January 2014): 255–60. http://dx.doi.org/10.4028/www.scientific.net/msf.775-776.255.
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The growing interest for natural materials as an environmentally friendly alternative for the substitution of energy intensive and non-sustainable synthetic materials, has motivated the use of lignocellulosic fibers as reinforcement of polymer composites. The malva fiber, a relatively unknown lignocellulosic fiber with potential for composite reinforcement, still needs to be characterized for possible engineer applications. Therefore, the present work analyzed the malva fiber by means of Fourier Transform Infra-red (FTIR) spectroscopy. The malva fiber FTIR spectrum revealed main absorption bands typical of any lignocellulosic fiber. However, some specific bands as well as bands broadening and intensity suggested particular activities for functional molecular groups in the malva fiber.
18
Ma, Shun Bin. "Infrared Spectrum Test and Analysis of Regenerated Cellulose Fibers." Advanced Materials Research 671-674 (March 2013): 1954–57. http://dx.doi.org/10.4028/www.scientific.net/amr.671-674.1954.
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In this paper, the infrared spectrum of regenerated fibers have been tested and analyzed, such as Lyocell fiber, Modal fiber, regenerated cellulose fiber and Bamboo pulp fiber. Test results shown that: Lyocell fiber, Modal fiber, Bamboo pulp fiber are similar to viscose fiber in their infrared spectrogram, but the transmittance of characteristic absorption peaks of them are different.
19
Fukui, Yuta, Tatsuya Teramua, and Tomoyuki Yoshimi. "Analysis of Fiber Drawing in Wet Spinning for Surface Roughness." MATEC Web of Conferences 333 (2021): 11006. http://dx.doi.org/10.1051/matecconf/202133311006.
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The drawing process behavior was investigated with focus on fiber stretching speed (spinning acceleration) to improve luster quality of fibers. Wet spinning method has a limitation of low luster at high spinning speed. It was determined that (1) luster quality could be evaluated by arithmetic average (RΔa) of fibers, which indicated the roughness, and (2) the roughness of the fiber was related to the spinning acceleration through the analysis of RΔa. Spinning acceleration was measured by chasing markers that were used to tie fibers. Regardless of the length of spinning bath, fibers were mainly stretched during the first stretching stage. Therefore, a multistep drawing method was used. In the case where the drawing ratio was 220% by one-step, RΔa was 10.1°; however by multi-step drawing (1st and 2nd drawing ratios were 148.3%), RΔa decreased to 8.3°. The multi-step drawing method enabled the reduction in fiber roughness by preventing a sudden change in fiber stress. In addition, high temperatures improved the fiber roughness. At high temperatures, roughness decreased despite the high acceleration because the fiber was easier to stretch than at low temperatures.
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Fukui, Yuta, Tatsuya Teramua, and Tomoyuki Yoshimi. "Analysis of Fiber Drawing in Wet Spinning for Surface Roughness." MATEC Web of Conferences 333 (2021): 11006. http://dx.doi.org/10.1051/matecconf/202133311006.
Full textAbstract:
The drawing process behavior was investigated with focus on fiber stretching speed (spinning acceleration) to improve luster quality of fibers. Wet spinning method has a limitation of low luster at high spinning speed. It was determined that (1) luster quality could be evaluated by arithmetic average (RΔa) of fibers, which indicated the roughness, and (2) the roughness of the fiber was related to the spinning acceleration through the analysis of RΔa. Spinning acceleration was measured by chasing markers that were used to tie fibers. Regardless of the length of spinning bath, fibers were mainly stretched during the first stretching stage. Therefore, a multistep drawing method was used. In the case where the drawing ratio was 220% by one-step, RΔa was 10.1°; however by multi-step drawing (1st and 2nd drawing ratios were 148.3%), RΔa decreased to 8.3°. The multi-step drawing method enabled the reduction in fiber roughness by preventing a sudden change in fiber stress. In addition, high temperatures improved the fiber roughness. At high temperatures, roughness decreased despite the high acceleration because the fiber was easier to stretch than at low temperatures.
21
Du, Zhao Qun, Ya Fen Luo, Yun Xu, Gang Zheng, and Wei Dong Yu. "Qualitative Characterization and Identification of Polylactic Fiber based on GC-MS, IR and Element Analysis." Advanced Materials Research 236-238 (May 2011): 1085–88. http://dx.doi.org/10.4028/www.scientific.net/amr.236-238.1085.
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Polylactic fiber is a new renewable and biodegradable polymer material for its better physical property and thermoplastic and biological properties, while there are no corresponding inspection method to characterize and identify polylactic fiber with other fibers. So, the present paper is to qualitative analyze the features of PLA fiber and identify it with general fibers, including Polyester, Polyamide, Polyacrylic, Diacetate, Cotton, Viscose and Silk fibers. Elementary analysis method is utilized to have the definite analysis of fiber purity degree and category by the corresoponding element contents of constructing elements. The experimental results show that there exist good accordance with the theoretical results, and is suitable for qualitative characterizaion and identification of fibers. Gas chromatography mass spectrum method is used to feature marker functional groups of these eight fibers, and to further have a qualitative analysis of each fiber. IR spectroscopy proves the qualitative identification on fiber category by the marker absorbing peaks of functional groups ranging from 650cm-1-2200cm-1. These results will be greatly helpful in the qualitative analysis and indectification of Polylactic fiber.
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Zhang, Su Feng, and Chun Lei Kang. "Crystal Structure Analysis on Aramid Fiber/Fibrids and Paper by Polarized Light Microscopy." Key Engineering Materials 531-532 (December 2012): 636–39. http://dx.doi.org/10.4028/www.scientific.net/kem.531-532.636.
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The crystal structure of aramid fibers is highly orientated. The structure of aramid fibers with various manufacturing processes and aramid paper sheets were analyzed and observed by using polarized light microscope (PLM). The change and its law of aramid fiber crystal structure in such processes as aramid fiber mamufaturing of aramid fiber/fibrids, forming of aramid paper sheets, and heat treatment were analysed. The relationship between the structural feature of aramid fibers and the performance of aramid paper was also discussed.
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Ellenburg, M. G., J. A. Hanigofsky, and W. J. Lackey. "Thermal stress analysis for coated fibers." Journal of Materials Research 9, no. 3 (March 1994): 789–96. http://dx.doi.org/10.1557/jmr.1994.0789.
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Thermal stresses induced during cooling from temperatures used for coating deposition were calculated for various fiber-coating systems. Systems under study include several types of carbon, alumina, and zirconia fibers. Coatings considered were TiB2, Si3N4, and SiC. Typical calculated stresses were on the order of 0 to 2 GPa. The results were used to analyze the effects of variable physical parameters such as coating thickness and crystallographic orientation on the stress levels. Each fiber-coating system was then compared using a nominal coating thickness of 5 μm in order to rank the various fiber-coating combinations. Among the results obtained, it was shown that orientation of deposited coatings usually leads to higher tensile stresses.
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Wacker, Michael J., Michelle M. Tehel, and Philip M. Gallagher. "Technique for quantitative RT-PCR analysis directly from single muscle fibers." Journal of Applied Physiology 105, no. 1 (July 2008): 308–15. http://dx.doi.org/10.1152/japplphysiol.00897.2007.
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The use of single-cell quantitative RT-PCR has greatly aided the study of gene expression in fields such as muscle physiology. For this study, we hypothesized that single muscle fibers from a biopsy can be placed directly into the reverse transcription buffer and that gene expression data can be obtained without having to first extract the RNA. To test this hypothesis, biopsies were taken from the vastus lateralis of five male subjects. Single muscle fibers were isolated and underwent RNA isolation ( technique 1) or placed directly into reverse transcription buffer ( technique 2). After cDNA conversion, individual fiber cDNA was pooled and quantitative PCR was performed using primer-probes for β2-microglobulin, glyceraldehyde-3-phosphate dehydrogenase, insulin-like growth factor I receptor, and glucose transporter subtype 4. The no RNA extraction method provided similar quantitative PCR data as that of the RNA extraction method. A third technique was also tested in which we used one-quarter of an individual fiber's cDNA for PCR (not pooled) and the average coefficient of variation between fibers was <8% (cycle threshold value) for all genes studied. The no RNA extraction technique was tested on isolated muscle fibers using a gene known to increase after exercise (pyruvate dehydrogenase kinase 4). We observed a 13.9-fold change in expression after resistance exercise, which is consistent with what has been previously observed. These results demonstrate a successful method for gene expression analysis directly from single muscle fibers.
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ĎUBEK, Marek, Peter MAKÝŠ, Silvia ĎUBEK, and Marek PETRO. "THE EVALUATION OF THE CONTENT OF FIBERS IN STEEL FIBER REINFORCED STRUCTURES AND IMAGE ANALYSIS." Journal of Civil Engineering and Management 24, no. 3 (May 24, 2018): 183–92. http://dx.doi.org/10.3846/jcem.2018.1642.
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The distribution of fiber orientation is an important factor in determining the mechanical properties of fiber-reinforced concrete. This study proposes a new image analysis technique for improving the evaluation accuracy of fiber orientation distribution in the sectional image of fibers reinforced concrete. The article is devoted to research the systematic evaluation of fiber-cuts through the image processing software. Mathematical representation of the final dispersal of fibers in steel fiber-reinforced concrete is incorporated into a programmed evaluation software. The software detects fibers and classified according to their axes of rotation angle and size of the identified ellipse detection area. Image processing algorithm and detecting fibers has been developed only for these research purposes. Detection area is randomly inserted via steel fiber reinforced concrete structure. The results show the average value of uniformity in the fiber-samples produced in the laboratory.
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Matheus Vinicius Falcão Moreira, Lorrane Carneiro Laranjeira Silva, Joyce Batista Azevedo, Pollyana da Silva Melo Cardoso, Josiane Dantas Viana Barbosa, and Daniel Vianna Goes Araujo. "Properties of Fibrous Composites with Polyester: A Comparative Analysis Between Sisal Fiber and Pet." JOURNAL OF BIOENGINEERING AND TECHNOLOGY APPLIED TO HEALTH 3, no. 4 (December 21, 2020): 334–40. http://dx.doi.org/10.34178/jbth.v3i4.139.
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Fiber-reinforced composites represent 75% of the application of these materials in several industrial segments. It has the purpose of improving technical characteristics and reducing environmental impact through the use of sustainable raw materials such as natural fibers and other fibers from industrial waste. In this sense, the objective of this work was to study and compare the mechanical properties of polyester composites (PL) reinforced with natural sisal fiber and residues of polyethylene terephthalate (PET) synthetic fibers. Initially, we evaluated the moisture and morphology of the fibers. The composites with PL matrix were obtained and the fiber concentration varied by 1%, 3%, and 5% by weight. In the composites, the mechanical properties under flexion and impact resistance were evaluated. We concluded that the level of reinforcement with sisal fibers did not significantly affect the mechanical properties. However, the PET fiber provided significant improvements in the properties of the composite. Thus, the composites reinforced with PET fiber residue have advantages in the development of new material with sustainable characteristics.
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Zughaibi, Torki A., and Robert R. Steiner. "Forensic Analysis of Polymeric Carpet Fibers Using Direct Analysis in Real Time Coupled to an AccuTOF™ Mass Spectrometer." Polymers 13, no. 16 (August 12, 2021): 2687. http://dx.doi.org/10.3390/polym13162687.
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Polymeric fibers are encountered in numerous forensic circumstances. This study focused on polymeric carpet fibers most encountered at a crime scene, which are nylons, polyesters and olefins. Analysis of the multiple polymer types was done using Direct Analysis in Real Time (DART™) coupled to an Accurate time-of-flight (AccuTOF™) mass spectrometer (MS). A DART gas temperature of 275 °C was determined as optimal. Twelve olefin, polyester, and nylon polymer standards were used for parameter optimization for the carpet fiber analysis. A successful identification and differentiation of all twelve polymer standards was completed using the DART-AccuTOF™. Thirty-two carpet samples of both known and unknown fiber composition were collected and subsequently analyzed. All samples with known fiber compositions were correctly identified by class. All of the remaining carpet samples with no known composition information were correctly identified by confirmation using Fourier-transform infrared spectroscopy (FTIR). The method was also capable of identifying sub-classes of nylon carpet fibers. The results exhibit the capability of DART-AccuTOF™ being applied as an addition to the sequence of tests conducted to analyze carpet fibers in a forensic laboratory.
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Xu, Yang, Wenzheng Xu, and Fenglin Huang. "Surface and Interface Analysis of Fibers Sputtered with Titanium Dioxide." Journal of Engineered Fibers and Fabrics 7, no. 4 (December 2012): 155892501200700. http://dx.doi.org/10.1177/155892501200700409.
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Nanoscale titanium dioxide (TiO2) films were deposited on the surface of polyester (PET), polypropylene (PP), and viscose fibers by using direct current (DC) reactive magnetron sputtering. The effect of different fibers on the surface structure and morphology of TiO2 thin films was investigated by atomic force microscopy (AFM). The cohesion and adhesion of the brittle titanium dioxide coating on the soft manmade fiber substrates was analyzed by scanning electron microscopy (SEM). The SEM images of coating interfaces were captured after TiO2 coated fibers were cut in a self-made simple apparatus. For comparison, the SEM images of the coating interfaces were captured after the coated fibers were broken in a single fiber strength tester. The results indicate that the characteristics of TiO2 deposited films were related to the structure and the morphology of the thin films which were determined by surface energy and roughness of different manmade fibers. Relatively smooth and high energy surface ultimately yielded uniformly deposited film and better adsorption to TiO2 clusters. The mechanical strength of the deposited film and the cohesion to the fiber substrate may be reduced for high surface roughness, because of the build-up of more micron cracks in the sputtering process.
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Liu, Shuai, Zheng Liu, and Xiu E. Bai. "Comparative Analysis of Fibers for Thermal Protective Clothing." Advanced Materials Research 627 (December 2012): 29–32. http://dx.doi.org/10.4028/www.scientific.net/amr.627.29.
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This paper firstly introduces the performance of some kinds of thermal protective clothing materials, for example, Nomex, Polysulfonamide fiber (PSA), polyphenylene sulfide fiber (PPS) and pre-oxidized fiber. Then mainly states the application status through investigation. According to their merits and demerits, we can improve clothes' comfort and functionality through blending. Finally, we should aim to gain more practical and environmental friendly thermal protective fibers.
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Tosi, Daniele, Carlo Molardi, Wilfried Blanc, Tiago Paixão, Paulo Antunes, and Carlos Marques. "Performance Analysis of Scattering-Level Multiplexing (SLMux) in Distributed Fiber-Optic Backscatter Reflectometry Physical Sensors." Sensors 20, no. 9 (May 2, 2020): 2595. http://dx.doi.org/10.3390/s20092595.
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Optical backscatter reflectometry (OBR) is a method for the interrogation of Rayleigh scattering occurring in each section of an optical fiber, resulting in a single-fiber-distributed sensor with sub-millimeter spatial resolution. The use of high-scattering fibers, doped with MgO-based nanoparticles in the core section, provides a scattering increase which can overcome 40 dB. Using a configuration-labeled Scattering-Level Multiplexing (SLMux), we can arrange a network of high-scattering fibers to perform a simultaneous scan of multiple fiber sections, therefore extending the OBR method from a single fiber to multiple fibers. In this work, we analyze the performance and boundary limits of SLMux, drawing the limits of detection of N-channel SLMux, and evaluating the performance of scattering-enhancement methods in optical fibers.
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Lee, T. E., B. Carragher, S. J. Watowich, W. A. McDade, and R. Josephs. "The Orientation of Sickle Hemoglobin Fibers Within Bundles as Determined by Correspondence Analysis." Proceedings, annual meeting, Electron Microscopy Society of America 46 (1988): 158–59. http://dx.doi.org/10.1017/s0424820100102870.
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Sickle cell anemia results from the polymerization of deoxygenated sickle hemoglobin (HbS) into long helical fibers. In red blood cells, and in vitro, fibers aggregate and align to form bundles which eventually crystallize. The fiber bundles distort the red cells and have been implicated in the catalysis of the polymerization reaction. Although the structure of the HbS fiber has been extensively investigated, the packing of fibers in bundles and the fiber rearrangements which accompany crystallization are poorly understood, even though these phenomena are of interest at both a clinical and a basic level. We have used correspondence analysis to establish that during crystallization fibers separate into rows of particles oriented in opposite directions.Axial projections in opposite directions down the HbS fiber are different and are related by mirror symmetry. Thus they can be used to determine the particle orientation in or out of the plane of projection. Figure 1 shows these projections for models of an HbS fiber.
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He, Jun Yong, Xiao Qing Huang, and Cheng Yu Tian. "Experimental Research and Numerical Analysis of Type Selection of Fiber for High Performance Hydraulic Concrete." Applied Mechanics and Materials 83 (July 2011): 85–90. http://dx.doi.org/10.4028/www.scientific.net/amm.83.85.
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Basalt fiber has the advantages of non-pollution and omnipotence, and expected to be widely used in the 21st Century. Therefore, more and more attention is paid on experimental research of the basalt fiber in the world. Firstly, according to the type selection principles and requirements of the fibers used in the hydraulic concrete, the contrast testing of the plastic shrinkage between fiber cement mortar and pure mortar is made. The experimental results showed that basalt fiber, polypropylene fiber and polyacrylonitrile fiber can be preliminarily chosen as reinforced fibers in high performance hydraulic concrete. Secondly, the impacts of the suggested three sorts of fibers on the interfacial shear stress of the fiber concrete are analyzed by numerical simulation，which showed that maximum interfacial shear stress of the basalt fiber concrete is minimum. So, the bond strength between basalt fiber and concrete is the best. Finally, taking both characteristics of basalt fiber and the increase of concrete costs into account, it can be concluded that top priority should be given to the basalt fiber rather than to other fibers for high performance hydraulic concrete.
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Zhang, Yin Jiang, Xiao Ping Xu, Xiang Yu Jin, and Zhi Feng Zhang. "Analysis of Elastic Recovery Property Based on the Mesh Structure of Spun-Laced Nonwovens." Advanced Materials Research 659 (January 2013): 19–24. http://dx.doi.org/10.4028/www.scientific.net/amr.659.19.
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By means of entanglement and consolidation, fibers form stable web in spun-laced nonwovens, it initially conceived fibers entanglement structure and analyzed morphological changes in the stress state, the result showed that the elastic recovery property of spun-laced nonwovens could be adjusted through the deformation resilience of water mesh and the elastic fiber itself. Meanwhile the mathematical model demonstrated the most common "u-shaped" entanglement method between fibers,so fiber I slip from the fiber Π which met the equation T1 = T0×e μ θ. Under the same water jet pressure condition, larger static friction coefficient (μ) or fiber coated Angle (θ) equals better fiber entanglement, more stable structure and better elasticity. Combining the actual production with ideal mesh model, the size relations of horizontal and longitudinal extension deformation about Δ L and Δ L' was discussed. The results showed that the elastic recovery property of nonwovens could be improved through changing fibers arrangement of the fiber web.
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Kwon, MiYeon, and Seung Goo Lee. "Analysis of the Interfacial Adhesion between a Stainless-Steel Fiber and an Epoxy Resin by the Single Fiber Microdroplet Test." Surfaces 3, no. 4 (October 24, 2020): 594–604. http://dx.doi.org/10.3390/surfaces3040040.
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In this study, the surfaces of the stainless-steel fibers of the kind primarily utilized in fiber-reinforced composite materials were modified by an acid treatment to increase the interfacial adhesion between the fibers and epoxy resins in composite materials. The interfacial shear strength between the resins and acid-treated fibers was determined by a single fiber microdroplet test, where the resin droplet was located at the center of the fiber. The etching effect at the surface of the fibers increased with the increase in the acid-treatment time. The interfacial shear strength between the stainless-steel fiber and epoxy resin increased with the increase in the specific surface area of contact between the fiber and resin. Furthermore, there was no significant deterioration in the mechanical properties of the stainless-steel fibers with the increase in the surface etching effect. The modification of the surfaces of the stainless-steel fibers by the acid treatment resulted in an increase in the interfacial shear strength between the fibers and resins. Thus, this study demonstrated the possibility of widening the scope of the applications of stainless-steel fiber/epoxy resin composites.
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Kleiza, V. "Modelling Light Transmission in a Fiber-Optical Reflection System." Nonlinear Analysis: Modelling and Control 9, no. 1 (January 25, 2004): 55–63. http://dx.doi.org/10.15388/na.2004.9.1.15170.
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Light transmission in the reflection fiber system, located in external optical media, has been investigated for application as sensors. The system was simulated by different models, including external cavity parameters such as the distance between light emitting and receiving fibers and mirror positioning distance. The sensitivity to a linear displacement of the sensors was studied as a function of the distance between the tips of the light emitting fiber and the center of the pair reflected light collecting fibers, by positioning a mirror. Physical fundamentals and operating principles of the advanced fiber optical sensors were revealed.
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Chen, Bin, Xiang He Peng, and Jing Hong Fan. "Observation on Hydrophilidae Cuticle and Analysis of Maximum Pullout Force of Branched Fiber." Key Engineering Materials 334-335 (March 2007): 901–4. http://dx.doi.org/10.4028/www.scientific.net/kem.334-335.901.
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Most structural materials existing in nature take the form of composite. After centuries’ evolution and modification, these natural materials gain highly optimized structures and prominent performances. The SEM observation on the cuticle of Hydrophilidae shows that the cuticle is a biocomposite reinforced with chitin fibers. The chitin fibers are embedded in a protein matrix of the cuticle in the form of layers. A kind of revolving fiber layup was found. Observation also shows that there is a kind of special branched fiber consisting of a long fiber and many short fibers. The maximum pullout force of the branched fiber is analyzed. The results show that the maximum pullout force of the branched fiber is distinctly larger than that of ordinary straight fiber.
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Prabhakar, N. R., J. Mitra, J. L. Overholt, and N. S. Cherniack. "Analysis of postinspiratory activity of phrenic motoneurons with chemical and vagal reflexes." Journal of Applied Physiology 61, no. 4 (October 1, 1986): 1499–509. http://dx.doi.org/10.1152/jappl.1986.61.4.1499.
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We examined the effects of chemical and reflex drives on the postinspiratory inspiratory activity (PIIA) of phrenic motoneurons using a single-fiber technique. Action potentials from “single” fibers were recorded from the C5 phrenic root together with contralateral mass phrenic activity (also from C5) in anesthetized, paralyzed, and artificially ventilated cats with intact vagus and carotid sinus nerves. Nerve fibers were classified as “early“ or “late” based on their onset of discharge in relation to mass phrenic activity during hyperoxic ventilation. Only the early fibers displayed PIIA but not the late fibers, even when their activity began earlier in inspiration with increased chemical drives. Isocapnic hypoxia increased, whereas hyperoxic hypercapnia shortened the duration of PIIA. Pulmonary stretch and “irritant” receptors inhibited PIIA. Hypercapnia and stimulation of peripheral chemoreceptors by lobeline excited both early and late units to the same extent, but hypoxic ventilation had a less marked excitatory effect on late fiber activity. Irritant receptor activation increased the activity of early more than late fibers. Hyperoxic hyperventilation eliminated late phrenic fiber activity, whereas early fibers became tonically active. Bilateral vagotomy abolished this sustained discharge in eight of nine early units, suggesting the importance of vagal afferents in producing tonic firing during hyperventilation. These results suggest that early and late phrenic fibers have different responses to chemical stimuli and to vagally mediated reflexes; late units do not discharge in postinspiratory period, whereas early fibers do; the PIIA is not affected in the same way by various chemical and vagal inputs; and early units that exhibit PIIA display tonic activity with hyperoxic hypocapnia.
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Mathura, Nadira, Duncan Cree, and Ryan P. Mulligan. "Characterization and Utilization of Coconut Fibers of the Caribbean." MRS Proceedings 1611 (2014): 95–104. http://dx.doi.org/10.1557/opl.2014.764.
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ABSTRACTIn many tropical countries coconut (coir) fiber production is a major source of income for rural communities. The Caribbean has an abundance of coconuts but research into utilizing its by-products is limited. Environmentally friendly coir fibers are natural polymers generally discarded as waste material in this region. Research has shown that coir fiber from other parts of the world has successfully been recycled. This paper therefore investigates the mechanical properties of Caribbean coir fiber for potential applications in civil engineering.Approximately four hundred fibers were randomly taken from a coir fiber stack and subjected to retting in both distilled and saline water media. The mechanical properties of both the retted and unretted coir fibers were evaluated at weekly increments for a period of 3 months. Tensile strength test, x-ray diffraction analysis and scanning electron micrographs were used to assess trends and relationships between fiber gauge lengths, diameter, tensile strength and Young’s modulus. Diameters ranged between 0.11 mm-0.46 mm, while fiber samples were no longer than 250 mm in length. The tensile strength and strain at break decreased as the gauge length increased for both unretted and retted fibers. The opposite occurred for the relationship between the gauge length and Young’s modulus. Additionally, the tensile strength and modulus decreased as the fiber diameter increased. Neither distilled nor saline water improved the coir fiber’s crystalline index. Scanning electron micrographs qualitatively assessed fiber surfaces and captured necking and microfibril degradation at the fractured ends.The analysis revealed that the tensile strength, modulus, strain at break and crystallinity properties of the Caribbean coir fibers were comparable to commercially available coir fiber which are currently being used in many building applications.
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Diniz, Jacqueline F. B., João M. P. Q. Delgado, Anderson F. Vilela, Ricardo S. Gomez, Arianne D. Viana, Maria J. Figueiredo, Diego D. S. Diniz, et al. "Drying of Sisal Fiber: A Numerical Analysis by Finite-Volumes." Energies 14, no. 9 (April 27, 2021): 2514. http://dx.doi.org/10.3390/en14092514.
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Vegetable fibers have inspired studies in academia and industry, because of their good characteristics appropriated for many technological applications. Sisal fibers (Agave sisalana variety), when extracted from the leaf, are wet and must be dried to reduce moisture content, minimizing deterioration and degradation for long time. The control of the drying process plays an important role to guarantee maximum quality of the fibers related to mechanical strength and color. In this sense, this research aims to evaluate the drying of sisal fibers in an oven with mechanical air circulation. For this purpose, a transient and 3D mathematical model has been developed to predict moisture removal and heating of a fiber porous bed, and drying experiments were carried out at different drying conditions. The advanced model considers bed porosity, fiber and bed moisture, simultaneous heat and mass transfer, and heat transport due to conduction, convection and evaporation. Simulated drying and heating curves and the hygroscopic equilibrium moisture content of the sisal fibers are presented and compared with the experimental data, and good concordance was obtained. Results of moisture content and temperature distribution within the fiber porous bed are presented and discussed in details. It was observed that the moisture removal and temperature kinetics of the sisal fibers were affected by the temperature and relative humidity of the drying air, being more accentuated at higher temperature and lower relative humidity, and the drying process occurred in a falling rate period.
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Cartee, Gregory D., Edward B. Arias, Carmen S. Yu, and Mark W. Pataky. "Novel single skeletal muscle fiber analysis reveals a fiber type-selective effect of acute exercise on glucose uptake." American Journal of Physiology-Endocrinology and Metabolism 311, no. 5 (November 1, 2016): E818—E824. http://dx.doi.org/10.1152/ajpendo.00289.2016.
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One exercise session can induce subsequently elevated insulin sensitivity that is largely attributable to greater insulin-stimulated glucose uptake by skeletal muscle. Because skeletal muscle is a heterogeneous tissue comprised of diverse fiber types, our primary aim was to determine exercise effects on insulin-independent and insulin-dependent glucose uptake by single fibers of different fiber types. We hypothesized that each fiber type featuring elevated insulin-independent glucose uptake immediately postexercise (IPEX) would be characterized by increased insulin-dependent glucose uptake at 3.5 h postexercise (3.5hPEX). Rat epitrochlearis muscles were isolated and incubated with 2-[3H]deoxyglucose. Muscles from IPEX and sedentary (SED) controls were incubated without insulin. Muscles from 3.5hPEX and SED controls were incubated ± insulin. Glucose uptake (2-[3H]deoxyglucose accumulation) and fiber type (myosin heavy chain isoform expression) were determined for single fibers dissected from the muscles. Major new findings included the following: 1) insulin-independent glucose uptake was increased IPEX in single fibers of each fiber type (types I, IIA, IIB, IIBX, and IIX), 2) glucose uptake values from insulin-stimulated type I and IIA fibers exceeded the values for the other fiber types, 3) insulin-stimulated glucose uptake for type IIX exceeded IIB fibers, and 4) the 3.5hPEX group vs. SED had greater insulin-stimulated glucose uptake in type I, IIA, IIB, and IIBX but not type IIX fibers. Insulin-dependent glucose uptake was increased at 3.5hPEX in each fiber type except for IIX fibers, although insulin-independent glucose uptake was increased IPEX in all fiber types (including type IIX). Single fiber analysis enabled the discovery of this fiber type-related difference for postexercise, insulin-stimulated glucose uptake.
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Zhang, Meng, Mei Hong Liu, and Yu Xian Li. "Manufacturing and Analysis of Non-Asbestos Sealing Gasket." Advanced Materials Research 936 (June 2014): 1937–41. http://dx.doi.org/10.4028/www.scientific.net/amr.936.1937.
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Under the fiber hybrid effect, the merits of organic and inorganic fibers were integrated. The appropriate organic and inorganic fibers were chosen to prepare the non-asbestos gasket which meets the usage requirements and has a good cost performance. The ratio of basic craft and materials for industrial production were obtained. Results indicate the new non-asbestos gasket which is made by non-asbestos fibers and enhanced rubber adhesive has reached the performance of similar international products and has formed our unique non-asbestos sealing materials.
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Guizani, Chamseddine, Mikaela Trogen, Hilda Zahra, Leena Pitkänen, Kaniz Moriam, Marja Rissanen, Mikko Mäkelä, Herbert Sixta, and Michael Hummel. "Fast and quantitative compositional analysis of hybrid cellulose-based regenerated fibers using thermogravimetric analysis and chemometrics." Cellulose 28, no. 11 (May 28, 2021): 6797–812. http://dx.doi.org/10.1007/s10570-021-03923-6.
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AbstractCellulose can be dissolved with another biopolymer in a protic ionic liquid and spun into a bicomponent hybrid cellulose fiber using the Ioncell® technology. Inside the hybrid fibers, the biopolymers are mixed at the nanoscale, and the second biopolymer provides the produced hybrid fiber new functional properties that can be fine-tuned by controlling its share in the fiber. In the present work, we present a fast and quantitative thermoanalytical method for the compositional analysis of man-made hybrid cellulose fibers by using thermogravimetric analysis (TGA) in combination with chemometrics. First, we incorporated 0–46 wt.% of lignin or chitosan in the hybrid fibers. Then, we analyzed their thermal decomposition behavior in a TGA device following a simple, one-hour thermal treatment protocol. With an analogy to spectroscopy, we show that the derivative thermogram can be used as a predictor in a multivariate regression model for determining the share of lignin or chitosan in the cellulose hybrid fibers. The method generated cross validation errors in the range 1.5–2.1 wt.% for lignin and chitosan. In addition, we discuss how the multivariate regression outperforms more common modeling methods such as those based on thermogram deconvolution or on linear superposition of reference thermograms. Moreover, we highlight the versatility of this thermoanalytical method—which could be applied to a wide range of composite materials, provided that their components can be thermally resolved—and illustrate it with an additional example on the measurement of polyester content in cellulose and polyester fiber blends. The method could predict the polyester content in the cellulose-polyester fiber blends with a cross validation error of 1.94 wt.% in the range of 0–100 wt.%. Finally, we give a list of recommendations on good experimental and modeling practices for the readers who want to extend the application of this thermoanalytical method to other composite materials.
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Prasad, Vishnu, G. Venkatachalam, Akshat Rathi, and S. Rajakumar. "Finite Element Analysis of Jute Fibre Made Hybrid Polymer Matrix Composite." Applied Mechanics and Materials 592-594 (July 2014): 363–67. http://dx.doi.org/10.4028/www.scientific.net/amm.592-594.363.
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During last few years, the interest in using natural fibers as reinforcement in polymers has increased significantly. Natural fibers are not only strong and lightweight but also relatively very cheap and bio-degradable. In this work, an investigation is carried out on jute fiber, a natural fiber. Jute fiber has gained interest in the composite field due to its superior specific properties compared to manmade synthetic fibers like glass, Kevlar, asbestos, etc. The present work describes the development and characterization of natural fiber based composites consisting of jute fiber as reinforcement and hybrid resin consisting of general purpose resin and cashew nut shell resin as matrix material. The composites are fabricated using hand lay-up technique. The tensile strength is studied using experimental and numerical analysis. The nature of hybrid matrix at different composition is also studied. The commercial Finite Element Analysis software ANSYS is used for numerical study.
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Kostelecká, Michaela, Daniel Kytýř, Veronika Koudelková, and Petr Koudelka. "Microscopic Analysis of Degradation of Polymer Fibers Subjected to Aggressive Environment." Advanced Materials Research 1122 (August 2015): 169–72. http://dx.doi.org/10.4028/www.scientific.net/amr.1122.169.
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The paper presents deals with degradation of polypropylene (PP) and polyvinyl-alcohol (PVA) fibers used as a reinforcement in fiber-cement boards. The fibers were immersed for 28 days in three different solutions generating corrosive environment similar to conditions observed during service life of the intended application. The solutions used in the study contained: i) 3 % NaCl, ii) 5 % NaOH and iii) 5 % H2SO4. To obtain information about long term and also short term behaviour of the fibers part of investigated specimens was inspected for damage after 7 day exposure to corrosive environment. The results show that the corrosive resistance of the recently proposed PVA fibers is comparable to PP fibers when in either case structure of the fibers was not violated.
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Jóźwicki, Mateusz Łukasz, Mateusz Gargol, Małgorzata Gil-Kowalczyk, and Paweł Mergo. "Commercially available granulates PMMA and PS - potential problems with the production of polymer optical fibers." Photonics Letters of Poland 12, no. 3 (September 30, 2020): 79. http://dx.doi.org/10.4302/plp.v12i3.1036.
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The aim of the study was to verify the usefulness of commercially available granulates of PMMA (poly (methyl methacrylate) and PS (polystyrene) for the production of polymer optical fibers by extrusion method. Samples were subjected to thermal processing in various conditions (different temperatures and exposure time). Thermal (TG/DTG) and spectroscopic (ATR/FT-IR) analyses were carried out to analyze changes in the samples. Based on FT-IR analysis of liquid monomers and granulates the conversion of double bonds was calculated, which gave us a picture of the degree of monomers conversion, crucial information from the technological point of view. Full Text: PDF ReferencesO. Ziemann, J. Krauser, P.E. Zamzow, W. Daum, POF Polymer Optical Fibersfor Data Communication (Berlin: Springer 2008). DirectLink P. Stajanca et al. "Solution-mediated cladding doping of commercial polymer optical fibers", Opt. Fiber Technol. 41, 227-234, (2018). CrossRef K. Peters, "Polymer optical fiber sensors—a review", Smart Mater. Struct., 20 013002 (2011) CrossRef J. Zubia and J. Arrue, "Plastic Optical Fibers: An Introduction to Their Technological Processes and Applications", Opt. Fiber Technol. 7 ,101-40 (2001) CrossRef M. Beckers, T. Schlüter, T. Gries, G. Seide, C.-A. Bunge, "6 - Fabrication techniques for polymer optical fibres", Polymer Optical Fibres, 187-199 (2017) CrossRef M. Niedźwiedź , M. Gil, M. Gargol , W. Podkościelny, P. Mergo, "Determination of the optimal extrusion temperature of the PMMA optical fibers", Phot. Lett. Poland 11, 7-9 (2019) CrossRef
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Zhang, Lijuan, and Weidong Yu. "Orientation image analysis of electrospun submicro-fibers based on Hough transform and Regionprops function." Textile Research Journal 87, no. 18 (October 14, 2016): 2263–74. http://dx.doi.org/10.1177/0040517516669070.
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Popular electrospun technology can only obtain submicron fibers and fiber membranes in random or in slight orientation, in fact, they are not real nanofibers. A fast-rotating drum-collector has been introduced into the electrospinning setup to improve the orientation of electrospun fibers/membranes and, more importantly, to stretch the electrospun fibers. The measured results indicate that: (1) the submicro-fiber orientation and the angle frequency distribution can be characterized quantitatively by Hough transform (HT) and Regionprops function (RF) approaches, and the accuracy of HT is relatively higher than that of RF; (2) through changing the drum speed, an extra stretching force is exerted on the submicro-fibers, so making them thinner; and (3) the higher the drum surface speed, the greater is the orientation of the electrospun fibers, and the finer and stronger the submicro-fibers; their diameter ranges from about 250 nm at zero drum speed to 170 nm at 7 m/min, and may even get into the nanoscale—that is, 1–100 nm.
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Lexell, J., C. Taylor, and M. Sjostrom. "Analysis of sampling errors in biopsy techniques using data from whole muscle cross sections." Journal of Applied Physiology 59, no. 4 (October 1, 1985): 1228–35. http://dx.doi.org/10.1152/jappl.1985.59.4.1228.
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Because of the large variability in the proportion of fiber types within a whole muscle, a single biopsy is a poor estimator of the fiber type proportion for a whole muscle. Data on the proportions of type I and II fibers, obtained from cross sections of whole human muscles (vastus lateralis) from young male individuals, have therefore been analyzed statistically in order to determine the sampling errors involved in muscle biopsy techniques. For the purpose of obtaining a good estimate of the fiber type proportion in a whole biopsy, counting all fibers is of great benefit compared with counting only half of the fiber number. The required number of biopsies to obtain a given sampling error of the mean proportion of fiber types in the whole muscle can vary by a factor of six. If less than three biopsies are taken from a muscle, there is a substantial reduction in sampling error taking biopsies with at least 600 fibers. For more than three biopsies there is a small gain in sampling greater than 150 fibers. The precision of the estimate of the mean proportion of fiber types for a group is increased with the number of biopsies per individual and number of individuals. In conclusion, for the muscle in this study, complete counting of three biopsies, each greater than 150 fibers, sampled from different depths of the muscle is recommended.
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Dorobantu, Dorel, Alin Jderu, Marius Enachescu, and Dominik Ziegler. "Fabrication of Optical Fibers with Multiple Coatings for Swelling-Based Chemical Sensing." Micromachines 12, no. 8 (August 10, 2021): 941. http://dx.doi.org/10.3390/mi12080941.
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We discuss distributed chemical sensing based on the swelling of coatings of optical fibers. Volume changes in the coating induce strain in the fiber’s glass core, provoking a local change in the refractive index which is detectable by distributed fiber optical sensing techniques. We describe methods to realize different coatings on a single fiber. Simultaneous detection of swelling processes all along the fiber opens the possibility to interrogate thousands of differently functionalized sections on a single fiber. Principal component analysis is used to enable sensors for environmental monitoring, food analysis, agriculture, water quality monitoring, or medical diagnostics.
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Ramesh, M., K. Palanikumar, and K. Hemachandra Reddy. "Impact Behaviour Analysis of Sisal/Jute and Glass Fiber Reinforced Hybrid Composites." Advanced Materials Research 984-985 (July 2014): 266–72. http://dx.doi.org/10.4028/www.scientific.net/amr.984-985.266.
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The fibers from naturally available resources are considered to have potential alternate reinforcing agent in polymer matrix composite materials due to their properties such as high strength, stiffness, degradable in nature and renewable in nature. In this study a lightweight, low cost and environment friendly hybrid composites are prepared by using sisal-jute-glass fibers as the reinforcement materials. There are three types of composites such as sisal/glass fiber reinforced polymer (SGFRP) composites, jute/glass fiber reinforced polymer (JGFRP) composites and sisal/jute/glass fiber reinforced polymer (SJGFRP) composites are prepared by hand lay-up process and underwent to charpy impact test in order to study their impact properties. Post impact induced damage, material failure mechanism, matrix cracking, fiber breakage and pullout was observed by using scanning electron microscopy (SEM) analysis. The results showed that the energy absorption and load carrying capacity of JGFRP composites are better and able to withstand higher loads than SGFRP composites and SJGFRP composites. It is further observed from the experiment, the inclusion of sisal and jute fibers with glass fiber reinforced polymer (GFRP) composites has gained good impact properties. It is suggested that these light weight sisal and jute fibers have been used as an alternative reinforcing material to synthetic fiber for medium load applications.
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Querido, Victor A., José Roberto M. d’Almeida, and Flávio A. Silva. "Development and analysis of sponge gourd (Luffa cylindrica L.) fiber-reinforced cement composites." BioResources 14, no. 4 (October 31, 2019): 9981–93. http://dx.doi.org/10.15376/biores.14.4.9981-9993.
Full textAbstract:
Sponge gourd (Luffa cylindrica L.) fiber-reinforced cement composites were developed and analyzed. Dried sponge gourd fruit’s fibrous vascular system forms a natural 3D network that can reinforce matrices in composite materials, diverting cracks along the complex array of 3D interfaces between the fibers and the cementitious matrix. To avoid fiber deterioration, the cement paste was modified by incorporating pozzolanic materials. The fibers were mechanically characterized by tensile testing of strips of the 3D natural fiber array and of single fibers extracted from the array. The fibers had an average tensile strength of 140 MPa and an average Young’s modulus up to 28 GPa. Image analysis showed that the fiber spatial distribution inside the 3D network was random. The modified cement paste was characterized by its workability (flow table test) and mechanical behavior (compression and three-point bending tests), with average results of 430 mm, 62.7 MPa, and 6.2 MPa, respectively. Under bending, the cement matrix collapsed after the first crack. The sponge gourd-cement composite manufactured with 1 wt% of fibers showed an average flexural strength of 9.2 MPa (approximately 50% greater than the unreinforced matrix). Importantly, the composite also presented a limited deflection-hardening behavior. These results support sponge gourd’s possible use as reinforcement in cement matrix composites.