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Sample records for glass fiber filter

  1. Plutonium recovery from spent glass fiber paper fine air filter

    Rovnyj, S.I.; Guzhavin, V.I.; Pyatin, N.P.; Evlanov, D.S.

    2002-01-01

    Investigations into the realizing technology of plutonium recovery from waste glass paper filters of fine purification were conducted. Two process schemes involving the nitro-fluoro-acid treatment of glass paper in the mixture of nitric and hydrofluoric acids and the previous alkali treatment of glass paper with the following nitro-fluoro-acid leaching of plutonium from pulp by the mixture of nitric and hydrofluoric acids were developed. Alkali, nitrate solutions and insoluble precipitants were analyzed for plutonium content [ru

  2. Consumer perception of risk associated with filters contaminated with glass fibers.

    Cummings, K M; Hastrup, J L; Swedrock, T; Hyland, A; Perla, J; Pauly, J L

    2000-09-01

    The filters in Eclipse, a new cigarette-like smoking article marketed by R. J. Reynolds Tobacco Company, are contaminated with glass fibers, fragments, and particles. Reported herein are the results of a study in which consumers were questioned about their opinions as to whether exposure to glass fibers in such a filter poses an added health risk beyond that from smoking and whether the manufacturer has an obligation to inform consumers about the glass contamination problem. The study queried 137 adults who were interviewed while waiting at a Division of Motor Vehicles office in Erie County, New York in 1997. All but one person expressed the view that the presence of glass fibers on the filters poses an added health risk beyond that associated with exposure to tobacco smoke alone. Nearly all expressed the position that the cigarette manufacturer has a duty to inform the public about the potential for glass exposure.

  3. Evidence for and implications of self-background of radon dosimeters with glass-fiber filters

    Put, L.W.; Lembrechts, J.; Graaf, E.R. van der; Stoop, P.

    2000-01-01

    The first national radon survey in the Netherlands was conducted in 1984 with passive radon dosimeters that contain glass-fiber diffusion filters. During the last few years, measurements of outdoor-radon concentrations and information in the literature suggested that these dosimeters may give falsely elevated readings. A systematic contribution would be present due to alpha particles from natural radionuclides in the glass-fiber filter producing tracks on the track-etch foil. In the framework of the quality assurance of their laboratories, the origin of this offset was systematically assessed by means of measurements of alpha and gamma radiation from the glass-fiber filters and by intercomparisons between different types of detectors at low radon concentrations. It was found that alpha particles from the decay of 214 Po in the glass-fiber filter are the main cause of the extra tracks (only 12% originates from decay of 212 Po), leading, for this type of filter, to an offset in concentration of approximately 8 Bq m -3 . The implications of this offset are discussed

  4. A Method for Cobalt and Cesium Leaching from Glass Fiber in HEPA Filter

    Kim, Gye Nam; Lee, Suk Chol; Yang, Hee Chul; Yoon, In Ho; Choi, Wang Kyu; Moon, Jei Kwon

    2011-01-01

    A great amount of radioactive waste has been generated during the operation of nuclear facilities. Recently, the storage space of a radioactive waste storage facility in the Korea Atomic Energy Research Institute (KAERI) was almost saturated with many radioactive wastes. So, the present is a point of time that a volume reduction of the wastes in a radioactive waste storage facility needs. There are spent HEPA filter wastes of about 2,226 sets in the radioactive waste storage facility in KAERI. All these spent filter wastes have been stored in accordance with their original form without any treatment. Up to now a compression treatment of these spent HEPA filters has been carried out to repack the compressed spent HEPA filters into a 200 liter drum for their volume reduction. Frame and separator are contaminated with a low concentration of nuclide, while the glass fiber is contaminated with a high concentration of nuclide. So, for the disposal of the glass filter to the environment, the glass fiber should be leached to lower its radioactive concentration first and then must be stabilized by solidification and so on. Therefore, it is necessary to develop a leaching process of glass fiber in a HEPA filter. Leaching is a separation technology, which is often used to remove a metal or a nuclide from a solid mixture with the help of a liquid solvent

  5. Evidence for and implications of self-background of radon dosimeters with glass-fiber filters

    Put, L.W.; Lembrechts, J.; van der Graaf, E.R.; Stoop, P.

    The first national radon survey in the Netherlands was conducted in 1984 with passive radon dosimeters that contain glass-fiber diffusion filters. During the last few years, measurements of outdoor-radon concentrations and information in the literature suggested to us that these dosimeters may give

  6. A device for uranium series leaching from glass fiber in HEPA filter

    Gye-Nam Kim; Hye-Min Park; Wang-Kyu Choi; Jei-Kwon Moon

    2012-01-01

    For the disposal of a high efficiency particulate air (HEPA) glass filter into the environment, the glass fiber should be leached to lower its radioactive concentration to the clearance level. To derive an optimum method for the removal of uranium series from a HEPA glass fiber, five methods were applied in this study. That is, chemical leaching by a 4.0 M HNO 3 -0.1 M Ce(IV) solution, chemical leaching by a 5 wt% NaOH solution, chemical leaching by a 0.5 M H 2 O 2 -1.0 M Na 2 CO 3 solution, chemical consecutive chemical leaching by a 4.0 M HNO 3 solution, and repeated chemical leaching by a 4.0 M HNO 3 solution were used to remove the uranium series. The residual radioactivity concentrations of 238 U, 235 U, 226 Ra, and 234 Th in glass after leaching for 5 h by the 4.0 M HNO 3 -0.1 M Ce(IV) solution were 2.1, 0.3, 1.1, and 1.2 Bq/g. The residual radioactivity concentrations of 238 U, 235 U, 226 Ra, and 234 Th in glass after leaching for 36 h by 4.0 M HNO 3 -0.1 M Ce(IV) solution were 76.9, 3.4, 63.7, and 71.9 Bq/g. The residual radioactivity concentrations of 238 U, 235 U, 226 Ra, and 234 Th in glass after leaching for 8 h by a 0.5 M H 2 O 2 -1.0 M Na 2 CO 3 solution were 8.9, 0.0, 1.91, and 6.4 Bq/g. The residual radioactivity concentrations of 238 U, 235 U, 226 Ra, and 234 Th in glass after consecutive leaching for 8 h by the 4.0 M HNO 3 solution were 2.08, 0.12, 1.55, and 2.0 Bq/g. The residual radioactivity concentrations of 238 U, 235 U, 226 Ra, and 234 Th in glass after three repetitions of leaching for 3 h by the 4.0 M HNO 3 solution were 0.02, 0.02, 0.29, and 0.26 Bq/g. Meanwhile, the removal efficiencies of 238 U, 235 U, 226 Ra, and 234 Th from the waste solution after its precipitation-filtration treatment with NaOH and alum for reuse of the 4.0 M HNO 3 waste solution were 100, 100, 93.3, and 100%. (author)

  7. Radiological results for samples collected on paired glass- and cellulose-fiber filters at the Sandia complex, Tonopah Test Range, Nevada

    Mizell, Steve A.; Shadel, Craig A.

    2016-01-01

    Airborne particulates are collected at U.S. Department of Energy sites that exhibit radiological contamination on the soil surface to help assess the potential for wind to transport radionuclides from the contamination sites. Collecting these samples was originally accomplished by drawing air through a cellulose-fiber filter. These filters were replaced with glass-fiber filters in March 2011. Airborne particulates were collected side by side on the two filter materials between May 2013 and May 2014. Comparisons of the sample mass and the radioactivity determinations for the side-by-side samples were undertaken to determine if the change in the filter medium produced significant results. The differences in the results obtained using the two filter types were assessed visually by evaluating the time series and correlation plots and statistically by conducting a nonparametric matched-pair sign test. Generally, the glass-fiber filters collect larger samples of particulates and produce higher radioactivity values for the gross alpha, gross beta, and gamma spectroscopy analyses. However, the correlation between the radioanalytical results for the glass-fiber filters and the cellulose-fiber filters was not strong enough to generate a linear regression function to estimate the glass-fiber filter sample results from the cellulose-fiber filter sample results.

  8. The use of nylon and glass fiber filter separators with different pore sizes in air-cathode single-chamber microbial fuel cells

    Zhang, Xiaoyuan; Cheng, Shaoan; Huang, Xia; Logan, Bruce E.

    2010-01-01

    on performance. Larger pore nylon mesh were used that had regular mesh weaves with pores ranging from 10 to 160 μm, while smaller pore-size nylon filters (0.2-0.45 μm) and glass fiber filters (0.7-2.0 μm) had a more random structure. The pore size of both types

  9. Ceramic fiber reinforced filter

    Stinton, David P.; McLaughlin, Jerry C.; Lowden, Richard A.

    1991-01-01

    A filter for removing particulate matter from high temperature flowing fluids, and in particular gases, that is reinforced with ceramic fibers. The filter has a ceramic base fiber material in the form of a fabric, felt, paper of the like, with the refractory fibers thereof coated with a thin layer of a protective and bonding refractory applied by chemical vapor deposition techniques. This coating causes each fiber to be physically joined to adjoining fibers so as to prevent movement of the fibers during use and to increase the strength and toughness of the composite filter. Further, the coating can be selected to minimize any reactions between the constituents of the fluids and the fibers. A description is given of the formation of a composite filter using a felt preform of commercial silicon carbide fibers together with the coating of these fibers with pure silicon carbide. Filter efficiency approaching 100% has been demonstrated with these filters. The fiber base material is alternately made from aluminosilicate fibers, zirconia fibers and alumina fibers. Coating with Al.sub.2 O.sub.3 is also described. Advanced configurations for the composite filter are suggested.

  10. Fluoride glass fiber optics

    Aggarwal, Ishwar D

    1991-01-01

    Fluoride Glass Fiber Optics reviews the fundamental aspects of fluoride glasses. This book is divided into nine chapters. Chapter 1 discusses the wide range of fluoride glasses with an emphasis on fluorozirconate-based compositions. The structure of simple fluoride systems, such as BaF2 binary glass is elaborated in Chapter 2. The third chapter covers the intrinsic transparency of fluoride glasses from the UV to the IR, with particular emphasis on the multiphonon edge and electronic edge. The next three chapters are devoted to ultra-low loss optical fibers, reviewing methods for purifying and

  11. Development of glass-fiber high-efficiency particulate air filters of high structural strength on the basis of the establishment of failure mechanisms

    Ruedinger, V.; Ricketts, C.I.; Wilhelm, J.G.; Alken, W.

    1987-01-01

    Practical experience from routine operation in nuclear installations as well as extensive bench and laboratory testing proved the structural limits of HEPA filters to be very low thus demonstrating the need for improvement of their structural strength. Detailed analysis of the courses and modes of filter failure under the challenge of dry air at high velocities and ambient temperature, together with additional measurements, allowed the establishment of the dominating mechanisms of filter failure. Based on this information, the following three options for effective and economical improvements in filter structural limits exist: (1) an increase in the tensile strength of the filter medium; (2) an increase in the stability of the pack to prevent the swelling of individual pleats; and (3) an increase in the area moment of inertia of the separators and a decrease in the sharpness of their edges. By using a reinforced glass fiber filter medium, the structural strength of standard size HEPA filters was increased to 31 kPa with dry air and beyond 10 kPa with air at high humidity. Prototype filters built with standard glass-fiber media and separators with inclined corrugations exhibited failure pressures of approximately 50 kPa under high velocity airflows. The combination of both types of improvements, together with other measures, will soon lead to even higher HEPA-filter structural strength

  12. The use of nylon and glass fiber filter separators with different pore sizes in air-cathode single-chamber microbial fuel cells

    Zhang, Xiaoyuan

    2010-01-01

    Separators are needed in microbial fuel cells (MFCs) to reduce electrode spacing and preventing electrode short circuiting. The use of nylon and glass fiber filter separators in single-chamber, air-cathode MFCs was examined for their effect on performance. Larger pore nylon mesh were used that had regular mesh weaves with pores ranging from 10 to 160 μm, while smaller pore-size nylon filters (0.2-0.45 μm) and glass fiber filters (0.7-2.0 μm) had a more random structure. The pore size of both types of nylon filters had a direct and predictable effect on power production, with power increasing from 443 ± 27 to 650 ± 7 mW m-2 for pore sizes of 0.2 and 0.45 μm, and from 769 ± 65 to 941 ± 47 mW m-2 for 10 to 160 μm. In contrast, changes in pore sizes of the glass fiber filters resulted in a relatively narrow change in power (732 ± 48 to 779 ± 43 mW m-2) for pore sizes of 0.7 to 2 μm. An ideal separator should increase both power density and Coulombic efficiency (CE). However, CEs measured for the different separators were inversely correlated with power production, demonstrating that materials which reduced the oxygen diffusion into the reactor also hindered proton transport to the cathode, reducing power production through increased internal resistance. Our results highlight the need to develop separators that control oxygen transfer and facilitate proton transfer to the cathode. © 2010 The Royal Society of Chemistry.

  13. A study of uniformity of elements deposition on glass fiber filters after collection of airborne particulate matter (PM-10), using a high-volume sampler.

    Marrero, Julieta; Rebagliati, Raúl Jiménez; Gómez, Darío; Smichowski, Patricia

    2005-12-15

    A study was conducted to evaluate the homogeneity of the distribution of metals and metalloids deposited on glass fiber filters collected using a high-volume sampler equipped with a PM-10 sampling head. The airborne particulate matter (APM)-loaded glass fiber filters (with an active surface of about 500cm(2)) were weighed and then each filter was cut in five small discs of 6.5cm of diameter. Each disk was mineralized by acid-assisted microwave (MW) digestion using a mixture of nitric, perchloric and hydrofluoric acids. Analysis was performed by axial view inductively coupled plasma optical emission spectrometry (ICP OES) and the elements considered were: Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sb, Ti and V. The validation of the procedure was performed by the analysis of the standard reference material NIST 1648, urban particulate matter. As a way of comparing the possible variability in trace elements distribution in a particular filter, the mean concentration for each element over the five positions (discs) was calculated and each element concentration was normalized to this mean value. Scatter plots of the normalized concentrations were examined for all elements and all sub-samples. We considered that an element was homogeneously distributed if its normalized concentrations in the 45 sub-samples were within +/-15% of the mean value ranging between 0.85 and 1.15. The study demonstrated that the 12 elements tested showed different distribution pattern. Aluminium, Cu and V showed the most homogeneous pattern while Cd and Ni exhibited the largest departures from the mean value in 13 out of the 45 discs analyzed. No preferential deposition was noticed in any sub-sample.

  14. Detection of irradiated foods with the photo-stimulated luminescence technique. Selection of a glass fiber filter for evaluating the performance of the PSL detectors

    Sekiguchi, Masayuki; Yamazaki, Masao; Goto, Michiko

    2008-01-01

    The PSL method is useful as a screening technique of irradiated foods to support efficient uses of TL analysis. Recently, there has been the growing need for the system check or calibration using the standard materials with spread of domestically -produced PSL detector. In this research, we characterized the PSL of several types of glass fiber filters and compared the cumulate photon counts of a selected filter of them (GA-100) with those of the SUERC paprika standard for PSL measurements. GA-100 filter showed a linear relationship between cumulate photon counts and irradiation doses, and the cumulate photon counts in the first 2 months after gamma rays irradiation (261Gy) were markedly decreased and reduced to about 5000 counts (the upper threshold of PSL) after 4 months. However, further long-term storage and dose increase was necessary to produce the filter with more adequate PSI property as a standard material. Light exposure (630Lux) within 3 minutes to GA-100 had little effect on the cumulate photon counts. GA-100 showed relatively less variation in cumulate photon counts compared with the paprika standard in a series of studies. (author)

  15. Resonant filtered fiber amplifiers

    Alkeskjold, Thomas Tanggaard; Laurila, Marko; Olausson, Christina Bjarnal Thulin

    2013-01-01

    In this paper we present our recent result on utilizing resonant/bandgap fiber designs to achieve high performance ytterbium doped fiber amplifers for achieving diffraction limited beam quality in large mode area fibers, robust bending performance and gain shaping for long wavelength operation...

  16. Determination of mercury in airborne particulate matter collected on glass fiber filters using high-resolution continuum source graphite furnace atomic absorption spectrometry and direct solid sampling

    Araujo, Rennan G.O., E-mail: rgoa01@terra.com.br [Laboratorio de Quimica Analitica Ambiental, Departamento de Quimica, Universidade Federal de Sergipe, Campus Sao Cristovao, 49.100-000, Sao Cristovao, SE (Brazil); Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); Vignola, Fabiola; Castilho, Ivan N.B. [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); Borges, Daniel L.G.; Welz, Bernhard [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); Instituto Nacional de Ciencia e Tecnologia do CNPq, INCT de Energia e Ambiente, Universidade Federal da Bahia, 40170-115 Salvador, BA (Brazil); Vale, Maria Goreti R. [Instituto Nacional de Ciencia e Tecnologia do CNPq, INCT de Energia e Ambiente, Universidade Federal da Bahia, 40170-115 Salvador, BA (Brazil); Instituto de Quimica, Universidade Federal do Rio Grande do Sul, 91501-970 Porto Alegre, RS (Brazil); Smichowski, Patricia [Comision Nacional de Energia Atomica (CNEA) and Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), Buenos Aires (Argentina); Ferreira, Sergio L.C. [Instituto Nacional de Ciencia e Tecnologia do CNPq, INCT de Energia e Ambiente, Universidade Federal da Bahia, 40170-115 Salvador, BA (Brazil); Instituto de Quimica, Universidade Federal da Bahia, 40170-290, Salvador, BA (Brazil); Becker-Ross, Helmut [Leibniz-Institut fuer Analytische Wissenschaften-ISAS-e.V., Department Berlin, 12489 Berlin (Germany)

    2011-05-15

    A study has been undertaken to assess the capability of high-resolution continuum source graphite furnace atomic absorption spectrometry for the determination of mercury in airborne particulate matter (APM) collected on glass fiber filters using direct solid sampling. The main Hg absorption line at 253.652 nm was used for all determinations. The certified reference material NIST SRM 1648 (Urban Particulate Matter) was used to check the accuracy of the method, and good agreement was obtained between published and determined values. The characteristic mass was 22 pg Hg. The limit of detection (3{sigma}), based on ten atomizations of an unexposed filter, was 40 ng g{sup -1}, corresponding to 0.12 ng m{sup -3} in the air for a typical air volume of 1440 m{sup 3} collected within 24 h. The limit of quantification was 150 ng g{sup -1}, equivalent to 0.41 ng m{sup -3} in the air. The repeatability of measurements was better than 17% RSD (n = 5). Mercury concentrations found in filter samples loaded with APM collected in Buenos Aires, Argentina, were between < 40 ng g{sup -1} and 381 {+-} 24 ng g{sup -1}. These values correspond to a mercury concentration in the air between < 0.12 ng m{sup -3} and 1.47 {+-} 0.09 ng m{sup -3}. The proposed procedure was found to be simple, fast and reliable, and suitable as a screening procedure for the determination of mercury in APM samples.

  17. Preliminary characterization of glass fiber sizing

    Petersen, Helga Nørgaard; Kusano, Yukihiro; Brøndsted, Povl

    2013-01-01

    Glass fiber surfaces are treated with sizing during manufacturing. Sizing consists of several components, including a film former and a silane coupling agent that is important for adhesion between glass fibers and a matrix. Although the sizing highly affects the composite interface and thus...... the strength of the composites, little is known about the structure and chemistry of the sizing. A part of sizing was extracted by soxhlet extraction. The fibers were subsequently burned and some fibers were merely burned for analysis of glass fiber and sizing. The results showed that the analyzed fibers had...

  18. Development of new radiopaque glass fiber posts

    Furtos, Gabriel; Baldea, Bogdan; Silaghi-Dumitrescu, Laura

    2016-01-01

    The aim of this study was to analyze the radiopacity and filler content of three experimental glass fiber posts (EGFP) in comparison with other glass/carbon fibers and metal posts from the dental market. Three EGFP were obtained by pultrusion of glass fibers in a polymer matrix based on 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy)-phenyl]propane (bis-GMA) and triethyleneglycol dimethacrylate (TEGDMA) monomers. Using intraoral sensor disks 27 posts, as well as mesiodistal sections of human molar and aluminum step wedges were radiographed for evaluation of radiopacity. The percentage compositions of fillers by weight and volume were investigated by combustion analysis. Two EGFP showed radiopacity higher than enamel. The commercial endodontic posts showed radiopacity as follows: higher than enamel, between enamel and dentin, and lower than dentin. The results showed statistically significant differences (p < 0.05) when evaluated with one-way ANOVA statistical analysis. According to combustion analyses, the filler content of the tested posts ranges between 58.84 wt.% and 86.02 wt.%. The filler content of the tested EGFP ranged between 68.91 wt.% and 79.04 wt.%. EGFP could be an alternative to commercial glass fiber posts. Future glass fiber posts are recommended to present higher radiopacity than dentin and perhaps ideally similar to or higher than that of enamel, for improved clinical detection. The posts with a lower radiopacity than dentin should be considered insufficiently radiopaque. The radiopacity of some glass fiber posts is not greatly influenced by the amount of filler. - Highlights: • AR glass fibers for dental applications • AR glass fibers have a great potential for obtaining radiopaque glass fiber posts. • Experimental AR glass fiber posts could be an alternative to commercial glass fiber posts for clinical application.

  19. Development of new radiopaque glass fiber posts

    Furtos, Gabriel, E-mail: gfurtos@yahoo.co.uk [Raluca Ripan Institute of Research in Chemistry, Babes-Bolyai University, Cluj-Napoca (Romania); Baldea, Bogdan [Dep. of Prosthodontics, Faculty of Dental Medicine, Timisoara (Romania); Silaghi-Dumitrescu, Laura [Raluca Ripan Institute of Research in Chemistry, Babes-Bolyai University, Cluj-Napoca (Romania)

    2016-02-01

    The aim of this study was to analyze the radiopacity and filler content of three experimental glass fiber posts (EGFP) in comparison with other glass/carbon fibers and metal posts from the dental market. Three EGFP were obtained by pultrusion of glass fibers in a polymer matrix based on 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy)-phenyl]propane (bis-GMA) and triethyleneglycol dimethacrylate (TEGDMA) monomers. Using intraoral sensor disks 27 posts, as well as mesiodistal sections of human molar and aluminum step wedges were radiographed for evaluation of radiopacity. The percentage compositions of fillers by weight and volume were investigated by combustion analysis. Two EGFP showed radiopacity higher than enamel. The commercial endodontic posts showed radiopacity as follows: higher than enamel, between enamel and dentin, and lower than dentin. The results showed statistically significant differences (p < 0.05) when evaluated with one-way ANOVA statistical analysis. According to combustion analyses, the filler content of the tested posts ranges between 58.84 wt.% and 86.02 wt.%. The filler content of the tested EGFP ranged between 68.91 wt.% and 79.04 wt.%. EGFP could be an alternative to commercial glass fiber posts. Future glass fiber posts are recommended to present higher radiopacity than dentin and perhaps ideally similar to or higher than that of enamel, for improved clinical detection. The posts with a lower radiopacity than dentin should be considered insufficiently radiopaque. The radiopacity of some glass fiber posts is not greatly influenced by the amount of filler. - Highlights: • AR glass fibers for dental applications • AR glass fibers have a great potential for obtaining radiopaque glass fiber posts. • Experimental AR glass fiber posts could be an alternative to commercial glass fiber posts for clinical application.

  20. Fiber glass reinforced structural materials for aerospace application

    Bartlett, D. H.

    1968-01-01

    Evaluation of fiber glass reinforced plastic materials concludes that fiber glass construction is lighter than aluminum alloy construction. Low thermal conductivity and strength makes the fiber glass material useful in cryogenic tank supports.

  1. Simulation of Glass Fiber Forming Processes

    Von der Ohe, Renate

    Two glass fiber forming processes have been simulated using FEM, which are the drawing of continuous glass fibers for reinforcement purposes and the spinning of discontinuous glass fibers - stone wool for insulation. The aim of this work was to set up a numerical model for each process, and to use...... this model in finding relationships between the production conditions and the resulting fiber properties. For both processes, a free surface with large deformation and radiative and convective heat transfer must be taken into account. The continuous fiber drawing has been simulated successfully......, and parametric studies have been made. Several properties that characterize the process have been calculated, and the relationship between the fictive temperature and the cooling rate of the fibers has been found. The model for the discontinuous fiber spinning was brought to the limits of the commercial code...

  2. Preliminary characterization of glass fiber sizing

    Noergaard Petersen, H.; Almdal, K. [Technical Univ. of Denmark. DTU Nanotech, Kgs. Lyngby (Denmark); Kusano, Y.; Broendsted, P. [Technical Univ. of Denmark. DTU Wind Energy, Risoe Campus, Roskilde (Denmark)

    2013-09-01

    Glass fiber surfaces are treated with sizing during manufacturing. Sizing consists of several components, including a film former and a silane coupling agent that is important for adhesion between glass fibers and a matrix. Although the sizing highly affects the composite interface and thus the strength of the composites, little is known about the structure and chemistry of the sizing. A part of sizing was extracted by soxhlet extraction. The fibers were subsequently burned and some fibers were merely burned for analysis of glass fiber and sizing. The results showed that the analyzed fibers had amounts of bonded and physisorbed sizing similar to what has been presented in literature. An estimated sizing thickness was found to be approximately 100 nm. It is indicated that an epoxy-resin containing film former and a polyethylene oxide lubricant are present, yet no silanes or other sizing components were identified in the extractant. (Author)

  3. Penetration of asbestos fibers in respirator filters

    Cheng, Yung-Sung; Pearson, S.D.; Rohrbacher, K.D.; Yeh, Hsu-Chi.

    1994-01-01

    Currently, the health risks associated with asbestos have restricted its use and created a growing asbestos abatement industry with a need for respirator filters that are effective for worker protection. The main purpose of this project is to determine the influence of fiber size, electrostatic charge, and flow rate on the penetration of asbestos fibers in respirator filter cartridges. The study includes four types of filters each tested at two flow rates: the AO-R57A, a dual cartridge HEPA filter tested at 16 and 42.5 L/min; the MSA-S, a dust and mist filter tested at 16 and 42.5 L/min; the MSA-A power filter tested at 32 and 85 L/min; and the 3M-8710, a low-efficiency disposable face mask filter tested at 32 and 85 L/min. The three types of asbestos fibers used (amosite, crocidolite, and chrysotile) ranged in length from 0.04-0.5 μm and in aspect ratio (ratio of length to diameter) from 3 to 60. The fibers were used in both charged and neutralized forms. The results from amosite fibers are reported here

  4. Silver metaphosphate glass wires inside silica fibers--a new approach for hybrid optical fibers.

    Jain, Chhavi; Rodrigues, Bruno P; Wieduwilt, Torsten; Kobelke, Jens; Wondraczek, Lothar; Schmidt, Markus A

    2016-02-22

    Phosphate glasses represent promising candidates for next-generation photonic devices due to their unique characteristics, such as vastly tunable optical properties, and high rare earth solubility. Here we show that silver metaphosphate wires with bulk optical properties and diameters as small as 2 µm can be integrated into silica fibers using pressure-assisted melt filling. By analyzing two types of hybrid metaphosphate-silica fibers, we show that the filled metaphosphate glass has only negligible higher attenuation and a refractive index that is identical to the bulk material. The presented results pave the way towards new fiber-type optical devices relying on metaphosphate glasses, which are promising materials for applications in nonlinear optics, sensing and spectral filtering.

  5. Benefits of glass fibers in solar fiber optic lighting systems.

    Volotinen, Tarja T; Lingfors, David H S

    2013-09-20

    The transmission properties and coupling of solar light have been studied for glass core multimode fibers in order to verify their benefits for a solar fiber optic lighting system. The light transportation distance can be extended from 20 m with plastic fibers to over 100 m with the kind of glass fibers studied here. A high luminous flux, full visible spectrum, as well as an outstanding color rendering index (98) and correlated color temperature similar to the direct sun light outside have been obtained. Thus the outstanding quality of solar light transmitted through these fibers would improve the visibility of all kinds of objects compared to fluorescent and other artificial lighting. Annual relative lighting energy savings of 36% in Uppsala, Sweden, and 76% in Dubai were estimated in an office environment. The absolute savings can be doubled by using glass optical fibers, and are estimated to be in the order of 550 kWh/year in Sweden and 1160 kWh/year in Dubai for one system of only 0.159 m(2) total light collecting area. The savings are dependent on the fiber length, the daily usage time of the interior, the type of artificial lighting substituted, the system light output flux, and the available time of sunny weather at the geographic location.

  6. Chalcogenide glass hollow core microstructured optical fibers

    Vladimir S. eShiryaev

    2015-03-01

    Full Text Available The recent developments on chalcogenide glass hollow core microstructured optical fibers (HC-MOFs are presented. The comparative analysis of simulated optical properties for chalcogenide HC-MOFs of negative-curvature with different size and number of capillaries is given. The technique for the manufacture of microstructured chalcogenide preforms, which includes the assembly of the substrate glass tube and 8-10 capillaries, is described. Further trends to improve the optical transmission in chalcogenide NCHCFs are considered.

  7. Thermoset composite recycling: Properties of recovered glass fiber

    Beauson, Justine; Fraisse, Anthony; Toncelli, C.

    2015-01-01

    Recycling of glass fiber thermoset polymer composite is a challenging topic and a process able to recover the glass fibers original properties in a limited cost is still under investigation. This paper focuses on the recycling technique separating the glass fiber from the matrix material. Four...

  8. Characterization and morphological properties of glass fiber ...

    Characterization and morphological properties of glass fiber reinforced epoxy composites fabricated under varying degrees of hand lay-up techniques. ... Hence, these composites are projected to possess better dimensional stability adaptable for high performance structural applications. Keywords: composite, interfacial ...

  9. Improved terbium-doped, lithium-loaded glass scintillator fibers

    Spector, G.B.; McCollum, T.; Spowart, A.R.

    1993-01-01

    An improved terbium-doped, 6 Li-loaded glass scintillator has been drawn into fibers. Tests indicate that the neutron detection response of the fibers is superior to the response with fibers drawn from the original terbium-doped glass. The new fibers offer less attenuation (1/e length of ∝40 cm) and improved gamma ray/neutron discrimination. The improved fibers will be incorporated in a scintillator fiber optic long counter for neutron detection. (orig.)

  10. Thermo-tunable hybrid photonic crystal fiber based on solution-processed chalcogenide glass nanolayers

    Markos, Christos

    2016-01-01

    the air-capillaries of the fiber based on a solution-processed glass approach. The deposited high-index layers revealed antiresonant transmission windows from similar to 500 nm up to similar to 1300 nm. We experimentally demonstrate for the first time the possibility to thermally-tune the revealed....../degrees C at 1300 nm. The proposed fiber device could potentially constitute an efficient route towards realization of monolithic tunable fiber filters or sensing elements....

  11. Modelling of the glass fiber length and the glass fiber length distribution in the compounding of short glass fiber-reinforced thermoplastics

    Kloke, P.; Herken, T.; Schöppner, V.; Rudloff, J.; Kretschmer, K.; Heidemeyer, P.; Bastian, M.; Walther, Dridger, A.

    2014-05-01

    The use of short glass fiber-reinforced thermoplastics for the production of highly stressed parts in the plastics processing industry has experienced an enormous boom in the last few years. The reasons for this are primarily the improvements to the stiffness and strength properties brought about by fiber reinforcement. These positive characteristics of glass fiber-reinforced polymers are governed predominantly by the mean glass fiber length and the glass fiber length distribution. It is not enough to describe the properties of a plastics component solely as a function of the mean glass fiber length [1]. For this reason, a mathematical-physical model has been developed for describing the glass fiber length distribution in compounding. With this model, it is possible on the one hand to optimize processes for the production of short glass fiber-reinforced thermoplastics, and, on the other, to obtain information on the final distribution, on the basis of which much more detailed statements can be made about the subsequent properties of the molded part. Based on experimental tests, it was shown that this model is able to accurately describe the change in glass fiber length distribution in compounding.

  12. Y-Si-Al-O-N Glass Fibers.

    The excellent mechanical properties and outstanding water corrosion resistance of Y -Si-Al-O- N glasses indicate that they are attractive candidate...materials for forming into high performance glass fibers. Fibers of glasses containing, respectively,3.2 and 6.6 wt% N were drawn freehand in air, and

  13. Recent Progress In Infrared Chalcogenide Glass Fibers

    Bornstein, A.; Croitoru, N.; Marom, E.

    1984-10-01

    Chalcogenide glasses containing elements like As, Ge, Sb and Se have been prepared. A new technique of preparing the raw material and subsequently drawing fibers has been devel-oped in order to avoid the forming of oxygen compounds. The fibers have been drawn by cru-cible and rod method from oxygen free raw material inside an Ar atmosphere glove box. The fibers drawn to date with air and glass cladding have a diameter of 50-500 pm and length of several meterd. Preliminary attenuation measurements indicate that the attentuation is better than 0.1 dB/cm and it is not affected even when the fiber is bent to 2 cm circular radius. The fibes were testes a CO laser beam and were not damaged at power densities below 10 kW/2cm2 CW &100 kw/cm using short pulses 75 n sec. The transmitted power density was 0.8 kW/cm2 which is an appropriate value to the needed for cutting and ablation of human tissues.

  14. Thermally controlled mid-IR band-gap engineering in all-glass chalcogenide microstructured fibers: a numerical study

    Barh, Ajanta; Varshney, Ravi K.; Pal, Bishnu P.

    2017-01-01

    Presence of photonic band-gap (PBG) in an all-glass low refractive index (RI) contrast chalcogenide (Ch) microstructured optical fibers (MOFs) is investigated numerically. The effect of external temperature on the position of band-gap is explored to realize potential fiber-based wavelength filters....... Then the temperature sensitivity of band-gaps is investigated to design fiber-based mid-IR wavelength filters/sensors....

  15. Fracture detection in concrete by glass fiber cloth reinforced plastics

    Shin, Soon-Gi; Lee, Sung-Riong

    2006-04-01

    Two types of carbon (carbon fiber and carbon powder) and a glass cloth were used as conductive phases and a reinforcing fiber, respectively, in polymer rods. The carbon powder was used for fabricating electrically conductive carbon powder-glass fiber reinforced plastic (CP-GFRP) rods. The carbon fiber tows and the CP-GFRP rods were adhered to mortar specimens using epoxy resin and glass fiber cloth. On bending, the electrical resistance of the carbon fiber tow attached to the mortar specimen increased greatly after crack generation, and that of the CP-GFRP rod increased after the early stages of deflection in the mortar. Therefore, the CP-GFRP rod is superior to the carbon fiber tow in detecting fractures. Also, by reinforcing with a glass fiber cloth reinforced plastic, the strength of the mortar specimens became more than twice as strong as that of the unreinforced mortar.

  16. Interactions between the glass fiber coating and oxidized carbon nanotubes

    Ku-Herrera, J.J., E-mail: jesuskuh@live.com.mx [Centro de Investigación Científica de Yucatán A.C., Unidad de Materiales, Calle 43 No.130, Col. Chuburná de Hidalgo. C.P., 97200 Mérida, Yucatán (Mexico); Avilés, F., E-mail: faviles@cicy.mx [Centro de Investigación Científica de Yucatán A.C., Unidad de Materiales, Calle 43 No.130, Col. Chuburná de Hidalgo. C.P., 97200 Mérida, Yucatán (Mexico); Nistal, A. [Instituto de Cerámica y Vidrio (ICV-CSIC), Kelsen 5, 28049 Madrid (Spain); Cauich-Rodríguez, J.V. [Centro de Investigación Científica de Yucatán A.C., Unidad de Materiales, Calle 43 No.130, Col. Chuburná de Hidalgo. C.P., 97200 Mérida, Yucatán (Mexico); Rubio, F.; Rubio, J. [Instituto de Cerámica y Vidrio (ICV-CSIC), Kelsen 5, 28049 Madrid (Spain); Bartolo-Pérez, P. [Departamento de Física Aplicada, Cinvestav, Unidad Mérida, C.P., 97310 Mérida, Yucatán (Mexico)

    2015-03-01

    Graphical abstract: - Highlights: • Oxidized multiwall carbon nanotubes (MWCNTs) were deposited onto E-glass fibers. • The role of the fiber coating on the deposition of MWCNTs on the fibers is studied. • A rather homogeneous deposition of MWCNTs is achieved if the coating is maintained. • Multiple oxygen-containing groups were found in the analysis of the fiber coating. • Evidence of chemical interaction between MWCNTs and the fiber coating was found. - Abstract: Chemically oxidized multiwall carbon nanotubes (MWCNTs) were deposited onto commercial E-glass fibers using a dipping procedure assisted by ultrasonic dispersion. In order to investigate the role of the fiber coating (known as “sizing”), MWCNTs were deposited on the surface of as-received E-glass fibers preserving the proprietary coating as well as onto glass fibers which had the coating deliberately removed. Scanning electron microscopy and Raman spectroscopy were used to assess the distribution of MWCNTs onto the fibers. A rather homogeneous coverage with high density of MWCNTs onto the glass fibers is achieved when the fiber coating is maintained. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and nuclear magnetic resonance (NMR) analyses of the chemical composition of the glass fiber coating suggest that such coating is a complex mixture with multiple oxygen-containing functional groups such as hydroxyl, carbonyl and epoxy. FTIR and XPS of MWCNTs over the glass fibers and of a mixture of MWCNTs and fiber coating provided evidence that the hydroxyl and carboxyl groups of the oxidized MWCNTs react with the oxygen-containing functional groups of the glass fiber coating, forming hydrogen bonding and through epoxy ring opening. Hydrogen bonding and ester formation between the functional groups of the MWCNTs and the silane contained in the coating are also possible.

  17. Interactions between the glass fiber coating and oxidized carbon nanotubes

    Ku-Herrera, J.J.; Avilés, F.; Nistal, A.; Cauich-Rodríguez, J.V.; Rubio, F.; Rubio, J.; Bartolo-Pérez, P.

    2015-01-01

    Graphical abstract: - Highlights: • Oxidized multiwall carbon nanotubes (MWCNTs) were deposited onto E-glass fibers. • The role of the fiber coating on the deposition of MWCNTs on the fibers is studied. • A rather homogeneous deposition of MWCNTs is achieved if the coating is maintained. • Multiple oxygen-containing groups were found in the analysis of the fiber coating. • Evidence of chemical interaction between MWCNTs and the fiber coating was found. - Abstract: Chemically oxidized multiwall carbon nanotubes (MWCNTs) were deposited onto commercial E-glass fibers using a dipping procedure assisted by ultrasonic dispersion. In order to investigate the role of the fiber coating (known as “sizing”), MWCNTs were deposited on the surface of as-received E-glass fibers preserving the proprietary coating as well as onto glass fibers which had the coating deliberately removed. Scanning electron microscopy and Raman spectroscopy were used to assess the distribution of MWCNTs onto the fibers. A rather homogeneous coverage with high density of MWCNTs onto the glass fibers is achieved when the fiber coating is maintained. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and nuclear magnetic resonance (NMR) analyses of the chemical composition of the glass fiber coating suggest that such coating is a complex mixture with multiple oxygen-containing functional groups such as hydroxyl, carbonyl and epoxy. FTIR and XPS of MWCNTs over the glass fibers and of a mixture of MWCNTs and fiber coating provided evidence that the hydroxyl and carboxyl groups of the oxidized MWCNTs react with the oxygen-containing functional groups of the glass fiber coating, forming hydrogen bonding and through epoxy ring opening. Hydrogen bonding and ester formation between the functional groups of the MWCNTs and the silane contained in the coating are also possible

  18. Mechanical Characterization of Basalt and Glass Fiber Epoxy Composite Tube

    Lapena, Mauro Henrique; Marinucci, Gerson

    2017-01-01

    The application of basalt fibers are possible in many areas thanks to its multiple and good properties. It exhibits excellent resistance to alkalis, similar to glass fiber, at a much lower cost than carbon and aramid fibers. In the present paper, a comparative study on mechanical properties of basalt and E-glass fiber composites was performed. Results of apparent hoop tensile strength test of ring specimens cut from tubes and the interlaminar shear stress (ILSS) test are presented. Tensile te...

  19. Phosphate-based glass fiber vs. bulk glass: Change in fiber optical response to probe in vitro glass reactivity.

    Massera, J; Ahmed, I; Petit, L; Aallos, V; Hupa, L

    2014-04-01

    This paper investigates the effect of fiber drawing on the thermal and structural properties as well as on the glass reactivity of a phosphate glass in tris(hydroxymethyl)aminomethane-buffered (TRIS) solution and simulated body fluid (SBF). The changes induced in the thermal properties suggest that the fiber drawing process leads to a weakening and probable re-orientation of the POP bonds. Whereas the fiber drawing did not significantly impact the release of P and Ca, an increase in the release of Na into the solution was noticed. This was probably due to small structural reorientations occurring during the fiber drawing process and to a slight diffusion of Na to the fiber surface. Both the powders from the bulk and the glass fibers formed a Ca-P surface layer when immersed in SBF and TRIS. The layer thickness was higher in the calcium and phosphate supersaturated SBF than in TRIS. This paper for the first time presents the in vitro reactivity and optical response of a phosphate-based bioactive glass (PBG) fiber when immersed in SBF. The light intensity remained constant for the first 48h after which a decrease with three distinct slopes was observed: the first decrease between 48 and 200h of immersion could be correlated to the formation of the Ca-P layer at the fiber surface. After this a faster decrease in light transmission was observed from 200 to ~425h in SBF. SEM analysis suggested that after 200h, the surface of the fiber was fully covered by a thin Ca-P layer which is likely to scatter light. For immersion times longer than ~425h, the thickness of the Ca-P layer increased and thus acted as a barrier to the dissolution process limiting further reduction in light transmission. The tracking of light transmission through the PBG fiber allowed monitoring of the fiber dissolution in vitro. These results are essential in developing new bioactive fiber sensors that can be used to monitor bioresponse in situ. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Mechanical characterization of glass fiber (woven roving/chopped strand mat E-glass fiber) reinforced polyester composites

    Bhaskar, V. Vijaya; Srinivas, Kolla

    2017-07-01

    Polymer reinforced composites have been replacing most of the engineering material and their applications become more and more day by day. Polymer composites have been analyzing from past thirty five years for their betterment for adapting more applications. This paper aims at the mechanical properties of polyester reinforced with glass fiber composites. The glass fiber is reinforced with polyester in two forms viz Woven Rovings (WRG) and Chopped Strand Mat (CSMG) E-glass fibers. The composites are fabricated by hand lay-up technique and the composites are cut as per ASTM Standard sizes for corresponding tests like flexural, compression and impact tests, so that flexural strength, compression strength, impact strength and inter laminar shear stress(ILSS) of polymer matrix composites are analyzed. From the tests and further calculations, the polyester composites reinforced with Chopped Strand Mat glass fiber have shown better performance against flexural load, compression load and impact load than that of Woven Roving glass fiber.

  1. Magnetically sensitive nanodiamond-doped tellurite glass fibers.

    Ruan, Yinlan; Simpson, David A; Jeske, Jan; Ebendorff-Heidepriem, Heike; Lau, Desmond W M; Ji, Hong; Johnson, Brett C; Ohshima, Takeshi; Afshar V, Shahraam; Hollenberg, Lloyd; Greentree, Andrew D; Monro, Tanya M; Gibson, Brant C

    2018-01-19

    Traditional optical fibers are insensitive to magnetic fields, however many applications would benefit from fiber-based magnetometry devices. In this work, we demonstrate a magnetically sensitive optical fiber by doping nanodiamonds containing nitrogen vacancy centers into tellurite glass fibers. The fabrication process provides a robust and isolated sensing platform as the magnetic sensors are fixed in the tellurite glass matrix. Using optically detected magnetic resonance from the doped nanodiamonds, we demonstrate detection of local magnetic fields via side excitation and longitudinal collection. This is a first step towards intrinsically magneto-sensitive fiber devices with future applications in medical magneto-endoscopy and remote mineral exploration sensing.

  2. Gaussian Filtering with Tapered Oil-Filled Photonic Bandgap Fibers

    Brunetti, Anna Chiara; Scolari, Lara; Weirich, Johannes

    2008-01-01

    A tunable Gaussian filter based on a tapered oil-filled photonic crystal fiber is demonstrated. The filter is centered at X=1364nm with a bandwidth (FWHM) of 237nm. Tunability is achieved by changing the temperature of the filter. A shift of 210nm of the central wavelength has been observed...

  3. Optical and mechanical anisotropy of oxide glass fibers

    Deubener, J.; Yue, Yuanzheng

    2012-01-01

    products [1], whereas stretching (frozen-in strain) results in optical and mechanical anisotropy of glass fibers, which is quantified inter alia by the specific birefringence [2]. The paper will stress the later effects by combining previous results on the structural origins of birefringence...... and anisotropic shrinkage in silica and phosphate fibers with recent studies on relaxation of optical anisotropy in E-glass fibers [3,4].......Upon fiber drawing, glass forming oxide melts are thermally quenched and mechanically stretched. High cooling rates (up to 106 K/min) of quenched glass fibres lead to higher enthalpy state of liquids, thereby, to higher fictive temperature than regular quenching (e.g. 20 K/min) of bulk glass...

  4. Thermomechanical analyses of phenolic foam reinforced with glass fiber mat

    Zhou, Jintang; Yao, Zhengjun; Chen, Yongxin; Wei, Dongbo; Wu, Yibing

    2013-01-01

    Highlights: • Over 10% glass fiber was used to reinforce phenolic foam in the shape of glass fiber mat. • Nucleating agents were used together with glass fiber mat and improved tensile strength of phenolic foam by 215.6%. • Nucleating agents lead to a smaller bubble size of phenolic foam. • The glass transition temperature of phenolic foam remained unchanged during the reinforcement. - Abstract: In this paper, thermomechanical analysis (TMA) and dynamic mechanical analysis were employed to study the properties of phenolic foam reinforced with glass fiber mat. Unreinforced phenolic foam was taken as the control sample. Mechanical tests and scanning electron microscopy were performed to confirm the results of TMA. The results show that glass fiber mat reinforcement improves the mechanical performance of phenolic foam, and nucleating agents improve it further. Phenolic foam reinforced with glass fiber mat has a smaller thermal expansion coefficient compared with unreinforced foam. The storage modulus of the reinforced phenolic foam is also higher than that in unreinforced foam, whereas the loss modulus of the former is lower than that of the latter. The glass transition temperature of the phenolic foam matrix remains unchanged during the reinforcement

  5. Characterization and Morphological Properties of Glass Fiber ...

    PROF HORSFALL

    used as the matrix for the glass fibre-epoxy resin formation. E- Glass fibre ... reinforcement of composites, coatings of materials, and other ..... composite for the manufacture of glass-ceramic materials ... reinforced epoxy composites with carbon.

  6. MICROWAVE INDUCED DEGRADATION OF GLASS FIBER REINFORCED POLYESTER FOR FIBER AND RESIN RECOVERY

    Ucar, Hülya; Nielsen, Rudi Pankratz; Søgaard, Erik Gydesen

    A solvolysis process to depolymerize the resin in glass fiber reinforced composites and recover the glass fibers has been investigated using microwave induced irradiation. The depolymerization was carried out in HNO3 with concentrations in the range of 1M-7M and in KOH with concentrations ranging...

  7. Radiographic testing of glass fiber reinforced plastic materials

    Babylas, E.

    1976-01-01

    The microradiography of glass fiber reinforced polymers allowed to obtain informations on the growth of defects during molding. A relation was established between microstructure and routine radiography. The conditions needed for obtaining good quality radiograms are analyzed [fr

  8. Fiber Fabrication Facility for Non-Oxide and Specialty Glasses

    Federal Laboratory Consortium — FUNCTION: Unique facility for the research, development, and fabrication of non-oxide and specialty glasses and fibers in support of Navy/DoD programs.DESCRIPTION:...

  9. Ceramic fiber reinforced glass-ceramic matrix composite

    Bansal, Narottam P. (Inventor)

    1993-01-01

    A slurry of BSAS glass powders is cast into tapes which are cut to predetermined sizes. Mats of continuous chemical vapor deposition (CVD)-SiC fibers are alternately stacked with these matrix tapes. This tape-mat stack is warm-pressed to produce a 'green' composite which is heated to burn out organic constituents. The remaining interim material is then hot-pressed to form a BSAS glass-ceramic fiber-reinforced composite.

  10. Multifunctionality in epoxy/glass fibers composites with graphene interphase

    Mahmood, Haroon

    2017-01-01

    In this project, the synergetic effect of a graphene interphase in epoxy/glass fibers composites was investigated by coating glass fibers (GF) with graphene oxide (GO) and reduced graphene oxide (rGO) nanosheets by an electrophoretic deposition (EPD) technique. Graphite oxide was prepared using modified Hummers method in which raw graphite powder was oxidized using potassium permanganate (KMnO4) in acidic solution. Using ultrasonic technique, the graphite oxide was dispersed homogenously in w...

  11. Deformation, Stress Relaxation, and Crystallization of Lithium Silicate Glass Fibers Below the Glass Transition Temperature

    Ray, Chandra S.; Brow, Richard K.; Kim, Cheol W.; Reis, Signo T.

    2004-01-01

    The deformation and crystallization of Li(sub 2)O (center dot) 2SiO2 and Li(sub 2)O (center dot) 1.6SiO2 glass fibers subjected to a bending stress were measured as a function of time over the temperature range -50 to -150 C below the glass transition temperature (Tg). The glass fibers can be permanently deformed at temperatures about 100 C below T (sub)g, and they crystallize significantly at temperatures close to, but below T,, about 150 C lower than the onset temperature for crystallization for these glasses in the no-stress condition. The crystallization was found to occur only on the surface of the glass fibers with no detectable difference in the extent of crystallization in tensile and compressive stress regions. The relaxation mechanism for fiber deformation can be best described by a stretched exponential (Kohlrausch-Williams-Watt (KWW) approximation), rather than a single exponential model.The activation energy for stress relaxation, Es, for the glass fibers ranges between 175 and 195 kJ/mol, which is considerably smaller than the activation energy for viscous flow, E, (about 400 kJ/mol) near T, for these glasses at normal, stress-free condition. It is suspected that a viscosity relaxation mechanism could be responsible for permanent deformation and crystallization of the glass fibers below T,

  12. Electret filter collects more exhaled albumin than glass condenser

    Jia, Ziru; Liu, Hongying; Li, Wang; Xie, Dandan; Cheng, Ke; Pi, Xitian

    2018-01-01

    Abstract In recent years, noninvasive diagnosis based on biomarkers in exhaled breath has been extensively studied. The procedure of biomarker collection is a key step. However, the traditional condenser method has low efficacy in collecting nonvolatile compounds especially the protein biomarkers in breath. To solve this deficiency, here we propose an electret filter method. Exhaled breath of 6 volunteers was collected with a glass condenser and an electret filter. The amount of albumin was analyzed. Furthermore, the difference of exhaled albumin between smokers and nonsmokers was evaluated. The electret filter method collected more albumin than the glass condenser method at the same breath volume level (P albumin than nonsmokers were also observed (P albumin than nonsmokers. PMID:29384875

  13. Machining of glass fiber reinforced polyamide

    2007-12-01

    Full Text Available The machinability of a 30 wt% glass fiber reinforced polyamide (PA was investigated by means of drilling tests. A disk was cut from an extruded rod and drilled on the flat surface: thrust was acquired during drilling at different drilling speed, feed rate and drill diameter. Differential scanning calorimetry (DSC and indentation were used to characterize PA so as to evaluate the intrinsic lack of homogeneity of the extruded material. In conclusion, it was observed that the chip formation mechanism affects the thrust dependence on the machining parameters. A traditional modeling approach is able to predict thrust only in presence of a continuous chip. In some conditions, thrust increases as drilling speed increases and feed rate decreases; this evidence suggests not to consider the general scientific approach which deals the machining of plastics in analogy with metals. Moreover, the thrust can be significantly affected by the workpiece fabrication effect, as well as by the machining parameters; therefore, the fabrication effect is not negligible in the definition of an optimum for the machining process.

  14. Radiation modification of glass fiber - reinforced plastics

    Allayarov, S.R.; Smirnov, Yu.N.; Lesnichaya, V.A.; Ol'khov, Yu.A.; Belov, G.P.; Dixon, D.A.; Kispert, L.D.

    2007-01-01

    Modification of glass fiber - reinforced plastics (GFRPs) by gamma-irradiation has been researched to receipt of polymeric composite materials. They were produced by the film - technology method and the cheapest thermoplastics (polythene, polyamide were used as polymeric matrixes for their manufacture. GFRPs were irradiated with Co 60 gamma-rays from a Gammatok-100 source in air and in vacuum. The strength properties of GFRPs and initial polymeric matrixes were investigated before and after radiolysis. Molecular - topological structure of the polymeric matrixes were tested by the method of thermomechanical spectroscopy. The strength properties of GFRPs depend on a parity of speeds of structural (physical) and chemical modification of the polymeric matrixes. These two processes proceed simultaneously. The structural modification includes physical transformation of polymers at preservation of their chemical structure. Covalent bonds between various macromolecules or between macromolecules and surface of fiberglasses are formed at the chemical modification of polymeric matrixes induced by radiation. Action of ionizing radiation on the used polymeric matrix results to its structurization (polythene) or to destruction (polyamide). Increasing of durability of GFRPs containing polythene is caused by formation of the optimum molecular topological structure of the polymeric matrix. (authors)

  15. Compressive yielding of tungsten fiber reinforced bulk metallic glass composites

    Clausen, B.; Lee, S.-Y.; Uestuendag, E.; Aydiner, C.C.; Conner, R.D.; Bourke, M.A.M

    2003-07-15

    In-situ uniaxial compression tests were conducted on four tungsten fiber reinforced bulk metallic glass matrix composites using neutron diffraction. The results were interpreted with a finite element model. Both phases were seen to approximately obey the von Mises yield criterion. The fibers were observed to yield first and then transfer load to the matrix.

  16. Compressive yielding of tungsten fiber reinforced bulk metallic glass composites

    Clausen, B.; Lee, S.-Y.; Uestuendag, E.; Aydiner, C.C.; Conner, R.D.; Bourke, M.A.M.

    2003-01-01

    In-situ uniaxial compression tests were conducted on four tungsten fiber reinforced bulk metallic glass matrix composites using neutron diffraction. The results were interpreted with a finite element model. Both phases were seen to approximately obey the von Mises yield criterion. The fibers were observed to yield first and then transfer load to the matrix

  17. High-Power ZBLAN Glass Fiber Lasers: Review and Prospect

    Xiushan Zhu

    2010-01-01

    Full Text Available ZBLAN (ZrF4-BaF2-LaF3-AlF3-NaF, considered as the most stable heavy metal fluoride glass and the excellent host for rare-earth ions, has been extensively used for efficient and compact ultraviolet, visible, and infrared fiber lasers due to its low intrinsic loss, wide transparency window, and small phonon energy. In this paper, the historical progress and the properties of fluoride glasses and the fabrication of ZBLAN fibers are briefly described. Advances of infrared, upconversion, and supercontinuum ZBLAN fiber lasers are addressed in detail. Finally, constraints on the power scaling of ZBLAN fiber lasers are analyzed and discussed. ZBLAN fiber lasers are showing promise of generating high-power emissions covering from ultraviolet to mid-infrared considering the recent advances in newly designed optical fibers, beam-shaped high-power pump diodes, beam combining techniques, and heat-dissipating technology.

  18. Environmental resistance and mechanical performance of basalt and glass fibers

    Wei Bin; Cao Hailin; Song Shenhua

    2010-01-01

    The treated basalt and glass fibers with sodium hydroxide and hydrochloric acid solutions for different times were analyzed, respectively. This paper summarized the mass loss ratio and the strength maintenance ratios of the fibers after treatment. The fibers' surface corrosion morphologies were characterized using scanning electron microscopy and their compositions were detected using energy dispersive X-ray spectroscopy. The acid resistance was much better than the alkali resistance for the basalt fibers. Nevertheless, for the glass fibers the situation is different: the acid resistance was almost the same as the alkali resistance. Among the two types of aqueous environments evaluated, the alkali solution is the most aggressive to the fibers' surface. The possible corrosion mechanisms are revealed.

  19. Study on the Metal Fiber Filter Modeling for Capturing Radioactive Aerosol

    Lee, Seunguk; Lee, Chanhyun; Park, Minchan; Lee, Jaekeun [EcoEnergy Research Institute, Busan (Korea, Republic of)

    2015-05-15

    The components of air cleaning system are demisters to remove entrained moisture, pre-filters to remove the bulk of the particulate matter, high efficiency particulate air (HEPA) filters, iodine absorbers(generally, activated carbon) and HEPA filters after the absorbers for redundancy and collection of carbon fines. The HEPA filters are most important components to prevent radioactive aerosols from being released to control room and adjacent environment. The Conventional HEPA filter has pleated media for low pressure drop. Consequently, the filters must provide high collection efficiency as well as low pressure drop. Unfortunately, conventional HEPA filters are made of glass fiber and polyester, and pose disposal issues since they cannot be recycled. In fact, 31,055 HEPA filters used in nuclear facilities in the U.S are annually disposed. The Analyses at face velocities 1cm/s and 10cm/s are also carried out, and they also show R2 value of 0.995. However, since official HEPA filter standards are established at face velocity of 5cm/s, this value will be used in further analysis. From the comparative studies carried out at different filter thickness and face velocities, a good correlation is found between the model and the experiment.

  20. Narrowband spectral filter based on biconical tapered fiber

    Celaschi, Sergio; Malheiros-Silveira, Gilliard N.

    2018-02-01

    The ease of fabrication and compactness of devices based on tapered optical fibers contribute to its potential using in several applications ranging from telecommunication components to sensing devices. In this work, we proposed, fabricated, and characterized a spectral filter made of biconical taper from a coaxial optical fiber. This filter is defined by adiabatically tapering a depressed-cladding fiber. The adiabatic taper profile obtained during fabrication prevents the interference of other modes than HE11 and HE12 ones, which play the main role for the beating phenomenon and the filter response. The evolution of the fiber shapes during the pulling was modeled by two coupled partial differential equations, which relate the normalized cross-section area, and the axial velocity of the fiber elongation. These equations govern the mass and axial momentum conservation. The numerical results of the filter characteristics are in good accordance with the experimental ones. The filter was packaged in order to let it ready for using in optical communication bands. The characteristics are: free spectral range (FSR) of 6.19 nm, insertion loss bellow 0.5 dB, and isolation > 20 dB at C-band. Its transmission spectrum extends from 1200 to 1600 nm where the optical fiber core supports monomode transmission. Such characteristics may also be interesting to be applied in sensing applications. We show preliminary numerical results assuming a biconic taper embedded into a dielectric media, showing promising results for electro-optic sensing applications.

  1. Development and testing the modular fireproof fine filters on the basis of glass paper

    Rovnyj, S.I.; Glagolenko, Yu.V.; Pyatin, N.P.; Tranchuk, O.A.; Maksimov, V.E.; Afanas'eva, E.V.

    2006-01-01

    Paper describes a procedure to fabricate modified module glass paper fine filters to trap radioactive substances (14 models). The mentioned filters are made of a glass paper ensuring their fire-resistance. Paper describes the procedure of service life tests of the designed filters and the efficient procedure to extract valuable components from the spent filters [ru

  2. Hybrid polymer photonic crystal fiber with integrated chalcogenide glass nanofilms

    Markos, Christos; Kubat, Irnis; Bang, Ole

    2014-01-01

    The combination of chalcogenide glasses with polymer photonic crystal fibers (PCFs) is a difficult and challenging task due to their different thermo-mechanical material properties. Here we report the first experimental realization of a hybrid polymer-chalcogenide PCF with integrated As2S3 glass...... nanofilms at the inner surface of the air-channels of a poly-methyl-methacrylate (PMMA) PCF. The integrated high refractive index glass films introduce distinct antiresonant transmission bands in the 480-900 nm wavelength region. We demonstrate that the ultra-high Kerr nonlinearity of the chalcogenide glass...

  3. Effect of fiber content on the properties of glass fiber-phenolic matrix composite

    Zaki, M.Y.; Shahid, M.R.; Subhani, T.; Sharif, M.N.

    2003-01-01

    Glass fiber-Phenolic matrix composite is used for the manufacturing of parts /components related to electronic and aerospace industry due to its high strength, dimensional stability and excellent electrical insulation properties. The evaluation of this composite material is necessary prior to make parts/components of new designs. In the present research, thermosetting phenolic plastic was reinforced with E-glass fiber in different fiber-to-resin ratios to produce composites of different compositions. Mechanical and electrical properties of these composite materials were evaluated with reference to the effect of fiber content variation in phenolic resin. (author)

  4. Continuous drawing of Bi-Ca-Sr-Cu-O glass fibers from a preform

    Zheng, H.; Hu, Y.; Mackenzie, J.D.

    1991-01-01

    Several issues related to drawing Bi-Ca-Sr-Cu-O glass fibers from a preform are discussed. Continuous drawing of Bi-Ca-Sr-Cu-O glass fibers was successfully accomplished. Bi-Ca-Sr-Cu-O glass fibers are drawn above the crystallization temperature. Minimizing crystallization of the glass preforms is a key for successful drawing of the glass fibers. Two effective means, high glass melting temperature and V 2 O 5 doping, have been used to minimize the crystallization of the preforms, thus assuring the continuous drawing of Bi-Ca-Sr-Cu-O glass fibers

  5. Physical Properties of AR-Glass Fibers in Continuous Fiber Spinning Conditions

    Lee, Ji-Sun; Lee, MiJai; Lim, Tae-Young; Lee, Youngjin; Jeon, Dae-Woo; Kim, Jin-Ho [Korea Institute of Ceramic Engineering and Technology, Jinju (Korea, Republic of); Hyun, Soong-Keun [Inha University, Incheon (Korea, Republic of)

    2017-04-15

    In this study, a glass fiber is fabricated using a continuous spinning process from alkali resistant (AR) glass with 4 wt%zirconia. In order to confirm the melting properties of the marble glass, the raw material is placed into a Pt crucible and melted at 1650 ℃ for 2 h, and then annealed. In order to confirm the transparency of the clear marble glass, the visible transmittance is measured and the fiber spinning condition is investigated by using high temperature viscosity measurements. A change in the diameter is observed according to the winding speed in the range of 100–900 rpm; it is also verified as a function of the fiberizing temperature in the range of 1200–1260 ℃. The optimum winding speed and spinning temperature are 500 rpm and 1240 ℃, respectively. The properties of the prepared spinning fiber are confirmed using optical microscope, tensile strength, modulus, and alkali-resistant tests.

  6. Characterization and reactivity of sodium aluminoborosilicate glass fiber surfaces

    Ortiz Rivera, Lymaris, E-mail: luo105@psu.edu [Materials Research Institute, Pennsylvania State University, University Park, PA 16802 (United States); Bakaev, Victor A.; Banerjee, Joy [Materials Research Institute, Pennsylvania State University, University Park, PA 16802 (United States); Mueller, Karl T. [Department of Chemistry, Pennsylvania State University, University Park, PA 16802 (United States); Pantano, Carlo G. [Materials Research Institute, Pennsylvania State University, University Park, PA 16802 (United States); Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA 16802 (United States)

    2016-05-01

    Highlights: • XPS revealed that these fiber surfaces contain sodium carbonate weathering products. • IGC–MS data confirms the products of acetic acid reaction with sodium carbonate. • NMR data shows two closely spaced, but distinct sodium carboxylate peaks. • Acetic acid reacts with both sodium in the glass and sodium in the sodium carbonate. - Abstract: Multicomponent complex oxides, such as sodium aluminoborosilicate glass fibers, are important materials used for thermal insulation in buildings and homes. Although the surface properties of single oxides, such as silica, have been extensively studied, less is known about the distribution of reactive sites at the surface of multicomponent oxides. Here, we investigated the reactivity of sodium aluminoborosilicate glass fiber surfaces for better understanding of their interface chemistry and bonding with acrylic polymers. Acetic acid (with and without a {sup 13}C enrichment) was used as a probe representative of the carboxylic functional groups in many acrylic polymers and adhesives. Inverse gas chromatography coupled to a mass spectrometer (IGC–MS), and solid state nuclear magnetic resonance (NMR), were used to characterize the fiber surface reactions and surface chemical structure. In this way, we discovered that both sodium ions in the glass surface, as well as sodium carbonate salts that formed on the surface due to the intrinsic reactivity of this glass in humid air, are primary sites of interaction with the carboxylic acid. Surface analysis by X-ray photoelectron spectroscopy (XPS) confirmed the presence of sodium carbonates on these surfaces. Computer simulations of the interactions between the reactive sites on the glass fiber surface with acetic acid were performed to evaluate energetically favorable reactions. The adsorption reactions with sodium in the glass structure provide adhesive bonding sites, whereas the reaction with the sodium carbonate consumes the acid to form sodium-carboxylate, H

  7. Stimulated Raman scattering in soft glass fluoride fibers

    Petersen, Christian; Dupont, Sune; Agger, Christian

    2011-01-01

    We have measured the absolute Raman gain spectrum in short fluoride soft glass fibers with a pump wavelength of 1650nm. We found a peak gain of gR ¼ 4:0 2 × 10−14mW−1.......We have measured the absolute Raman gain spectrum in short fluoride soft glass fibers with a pump wavelength of 1650nm. We found a peak gain of gR ¼ 4:0 2 × 10−14mW−1....

  8. Midinfrared optical rogue waves in soft glass photonic crystal fiber

    Buccoliero, Daniel; Steffensen, Henrik; Ebendorff-Heidepriem, Heike

    2011-01-01

    We investigate numerically the formation of extreme events or rogue waves in soft glass tellurite fibers and demonstrate that optical loss drastically diminishes shot-to-shot fluctuations characteristic of picosecond pumped supercontinuum (SC). When loss is neglected these fluctuations include...... distributions. Our results thus implicitly show that rogue waves will not occur in any SC spectrum that is limited by loss, such as commercial silica fiber based SC sources. © 2011 Optical Society of America....

  9. Effects of accelerated artificial daylight aging on bending strength and bonding of glass fibers in fiber-embedded maxillofacial silicone prostheses.

    Hatamleh, Muhanad M; Watts, David C

    2010-07-01

    The purpose of this study was to test the effect of different periods of accelerated artificial daylight aging on bond strength of glass fiber bundles embedded into maxillofacial silicone elastomer and on bending strength of the glass fiber bundles. Forty specimens were fabricated by embedding resin-impregnated fiber bundles (1.5-mm diameter, 20-mm long) into maxillofacial silicone elastomer. Specimens were randomly allocated into four groups, and each group was subjected to different periods of accelerated daylight aging as follows (in hours); 0, 200, 400, and 600. The aging cycle included continuous exposure to quartz-filtered visible daylight (irradiance 760 W/m(2)) under an alternating weathering cycle (wet for 18 minutes, dry for 102 minutes). Pull-out tests were performed to evaluate bond strength between fiber bundles and silicone using a universal testing machine at 1 mm/min crosshead speed. Also a three-point bending test was performed to evaluate bending strength of the fiber bundles. One-way ANOVA and Bonferroni post hoc tests were carried out to detect statistical significance (p aging only. After 200 hours of exposure to artificial daylight and moisture conditions, bond strength between glass fibers and heat-cured silicones is optimal, and the bending strength of the glass fiber bundles is enhanced.

  10. Fiber glass-bioactive glass composite for bone replacing and bone anchoring implants.

    Vallittu, Pekka K; Närhi, Timo O; Hupa, Leena

    2015-04-01

    Although metal implants have successfully been used for decades, devices made out of metals do not meet all clinical requirements, for example, metal objects may interfere with some new medical imaging systems, while their stiffness also differs from natural bone and may cause stress-shielding and over-loading of bone. Peer-review articles and other scientific literature were reviewed for providing up-dated information how fiber-reinforced composites and bioactive glass can be utilized in implantology. There has been a lot of development in the field of composite material research, which has focused to a large extent on biodegradable composites. However, it has become evident that biostable composites may also have several clinical benefits. Fiber reinforced composites containing bioactive glasses are relatively new types of biomaterials in the field of implantology. Biostable glass fibers are responsible for the load-bearing capacity of the implant, while the dissolution of the bioactive glass particles supports bone bonding and provides antimicrobial properties for the implant. These kinds of combination materials have been used clinically in cranioplasty implants and they have been investigated also as oral and orthopedic implants. The present knowledge suggests that by combining glass fiber-reinforced composite with particles of bioactive glass can be used in cranial implants and that the combination of materials may have potential use also as other types of bone replacing and repairing implants. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  11. Effects of bond primers on bending strength and bonding of glass fibers in fiber-embedded maxillofacial silicone prostheses.

    Hatamleh, Muhanad M; Watts, David C

    2011-02-01

    To evaluate the effect of three commonly used bond primers on the bending strength of glass fibers and their bond strength to maxillofacial silicone elastomer after 360 hours of accelerated daylight aging. Eighty specimens were fabricated by embedding resin-impregnated fiber bundles (1.5-mm diameter, 20-mm long) into maxillofacial silicone elastomer M511 (Cosmesil). Twenty fiber bundles served as control and did not receive surface treatment with primers, whereas the remaining 60 fibers were treated with three primers (n = 20): G611 (Principality Medical), A-304 (Factor II), and A-330-Gold (Factor II). Forty specimens were dry stored at room temperature (23 ± 1°C) for 24 hours, and the remaining specimens were aged using an environmental chamber under accelerated exposure to artificial daylight for 360 hours. The aging cycle included continuous exposure to quartz-filtered visible daylight (irradiance 760 W/m(2) ) under an alternating weathering cycle (wet for 18 minutes, dry for 102 minutes). Pull-out tests were performed to evaluate bond strength between fiber bundles and silicone using a universal testing machine at 1 mm/min crosshead speed. A 3-point bending test was performed to evaluate the bending strength of the fiber bundles. One-way Analysis of Variance (ANOVA), Bonferroni post hoc test, and an independent t-test were carried out to detect statistical significances (p accelerated daylight aging. Treatment with primer and accelerated daylight aging increased bending strength of glass fibers. © 2011 by The American College of Prosthodontists.

  12. Improving the interfacial and mechanical properties of short glass fiber/epoxy composites by coating the glass fibers with cellulose nanocrystals

    A. Asadi; M. Miller; Robert Moon; K. Kalaitzidou

    2016-01-01

    In this study, the interfacial and mechanical properties of cellulose nanocrystals (CNC) coated glass fiber/epoxy composites were investigated as a function of the CNC content on the surface of glass fibers (GF). Chopped GF rovings were coated with CNC by immersing the GF in CNC (0–5 wt%) aqueous suspensions. Single fiber fragmentation (SFF) tests showed that the...

  13. Ytterbium-Phosphate Glass for Microstructured Fiber Laser

    Ryszard Stępień

    2014-06-01

    Full Text Available In the paper, we report on the development of a synthesis and melting method of phosphate glasses designed for active microstructured fiber manufacturing. Non-doped glass synthesized in a P2O5-Al2O3-BaO-ZnO-MgO-Na2O oxide system served as the matrix material; meanwhile, the glass was doped with 6 mol% (18 wt% of Yb2O3, as fiber core. The glasses were well-fitted in relation to optical (refractive index and thermal proprieties (thermal expansion coefficient, rheology. The fiber with the Yb3+-doped core, with a wide internal photonic microstructure for a laser pump, as well as with a high relative hole size in the photonic outer air-cladding, was produced. The laser built on the basis of this fiber enabled achieving 8.07 W of output power with 20.5% slope efficiency against the launched pump power, in single-mode operation M2 = 1.59, from a 53 cm-long cavity.

  14. Infrared Supercontinuum Generation in Soft-glass Fibers

    Agger, Christian

    This Ph.D.-project presents numerical simulations of supercontinuum (SC) generation in optical fiber laser systems based on various soft-glass materials. Extensive numerical modeling is performed in order to understand and characterize the generated SC. This includes a review of the generalized...

  15. Effects of moisture on glass fiber-reinforced polymer composites

    Alzamora Guzman, Vladimir Joel; Brøndsted, Povl

    2015-01-01

    performance of wind turbine blades over their lifetime. Here, environmental moisture conditions were simulated by immersing glass fiber-reinforced polymer specimens in salt water for a period of up to 8 years. The mechanical properties of specimens were analyzed before and after immersion to evaluate...

  16. Investigations on the Broadband Shielding Effectiveness of Metallized Glass Fiber

    Coburn, William

    1998-01-01

    ...) is an E-glass fiber metallized with Al and processed into a nonwoven mat. When formed into a mat, the MGFs lead to an effective sample conductivity, sigma eff, which is the parameter of interest for electromagnetic shielding in the RF region...

  17. Production of continuous glass fiber using lunar simulant

    Tucker, Dennis S.; Ethridge, Edwin C.; Curreri, Peter A.

    1991-01-01

    The processing parameters and mechanical properties of glass fibers pulled from simulated lunar basalt are tested. The simulant was prepared using a plasma technique. The composition is representative of a low titanium mare basalt (Apollo sample 10084). Lunar gravity experiments are to be performed utilizing parabolic aircraft free-fall maneuvers which yield 30 seconds of 1/6-g per maneuver.

  18. In vitro bioactivity and cytotoxicity of chemically treated glass fibers

    Ângela Leão Andrade

    2004-12-01

    Full Text Available Samples of a commercial glass fiber FM® (Fiber Max were used to test the efficacy of a chemical sol-gel surface treatment to enhance their bioactivity. After treatment with tetraethoxysilane (TEOS, individual fiber samples were soaked into a simulated body fluid (SBF solution, from which they were removed at intervals of 5 and 10 days. Micrographs obtained by scanning electron microscopy (SEM analysis of samples chemically treated with TEOS revealed the formation of a hydroxyapatite (HA coating layer after 5 days into SBF solution. Fourier transform infrared spectroscopic (FTIR analyses confirmed that the coating layer has P-O vibration bands characteristic of HA. The in vitro cytotoxicity was evaluated using a direct contact test, minimum essential medium elution test (ISO 10993-5 and MTT assay. Fibers immersed in SBF and their extracts exhibited lower cytotoxicity than the controls not subjected to immersion, suggesting that SBF treatment improves the biocompatibility of the fiber.

  19. Cross-correlated imaging of distributed mode filtering rod fiber

    Laurila, Marko; Barankov, Roman; Jørgensen, Mette Marie

    2013-01-01

    We analyze the modal properties of an 85μm core distributed mode filtering rod fiber using cross-correlated (C2) imaging. We evaluate suppression of higher-order modes (HOMs) under severely misaligned mode excitation and identify a single-mode regime where HOMs are suppressed by more than 20dB....

  20. Removing Pathogens Using Nano-Ceramic-Fiber Filters

    Tepper, Frederick; Kaledin, Leonid

    2005-01-01

    A nano-aluminum-oxide fiber of only 2 nanometers in diameter was used to develop a ceramic-fiber filter. The fibers are electropositive and, when formulated into a filter material (NanoCeram(TradeMark)), would attract electro-negative particles such as bacteria and viruses. The ability to detect and then remove viruses as well as bacteria is of concern in space cabins since they may be carried onboard by space crews. Moreover, an improved filter was desired that would polish the effluent from condensed moisture and wastewater, producing potable drinking water. A laboratory- size filter was developed that was capable of removing greater than 99.9999 percent of bacteria and virus. Such a removal was achieved at flow rates hundreds of times greater than those through ultraporous membranes that remove particles by sieving. Because the pore size of the new filter was rather large as compared to ultraporous membranes, it was found to be more resistant to clogging. Additionally, a full-size cartridge is being developed that is capable of serving a full space crew. During this ongoing effort, research demonstrated that the filter media was a very efficient adsorbent for DNA (deoxyribonucleic acid), RNA (ribonucleic acid), and endotoxins. Since the adsorption is based on the charge of the macromolecules, there is also a potential for separating proteins and other particulates on the basis of their charge differences. The separation of specific proteins is a major new thrust of biotechnology. The principal application of NanoCeram filters is based on their ability to remove viruses from water. The removal of more than 99.9999 percent of viruses was achieved by a NanoCeram polishing filter added to the effluent of an existing filtration device. NanoCeram is commercially available in laboratory-size filter discs and in the form of a syringe filter. The unique characteristic of the filter can be demonstrated by its ability to remove particulate dyes such as Metanyl yellow. Its

  1. Glass pipette-carbon fiber microelectrodes for evoked potential recordings

    Moraes M.F.D.

    1997-01-01

    Full Text Available Current methods for recording field potentials with tungsten electrodes make it virtually impossible to use the same recording electrode also as a lesioning electrode, for example for histological confirmation of the recorded site, because the lesioning procedure usually wears off the tungsten tip. Therefore, the electrode would have to be replaced after each lesioning procedure, which is a very high cost solution to the problem. We present here a low cost, easy to make, high quality glass pipette-carbon fiber microelectrode that shows resistive, signal/noise and electrochemical coupling advantages over tungsten electrodes. Also, currently used carbon fiber microelectrodes often show problems with electrical continuity, especially regarding electrochemical applications using a carbon-powder/resin mixture, with consequent low performance, besides the inconvenience of handling such a mixture. We propose here a new method for manufacturing glass pipette-carbon fiber microelectrodes with several advantages when recording intracerebral field potentials

  2. Fiber fuse light-induced continuous breakdown of silica glass optical fiber

    Todoroki, Shin-ichi

    2014-01-01

    This book describes the fiber fuse phenomenon that causes a serious problem for the present optical communication systems. High-power light often brings about catastrophic damage to optical devices. Silica glass optical fibers with ultralow transmission loss are not the exception. A fiber fuse appears in a heated region of the fiber cable delivering a few watts of light and runs toward the light source destroying its core region. Understanding this phenomenon is a necessary first step in the development of future optical communication systems. This book provides supplementary videos and photog

  3. Remote Fiber Laser Cutting System for Dismantling Glass Melter - 13071

    Mitsui, Takashi; Miura, Noriaki [IHI Corporation, 1 Shin-Nakahara-cho, Isogo-ku, Yokohama, Kanagawa (Japan); Oowaki, Katsura; Kawaguchi, Isao [IHI Inspection and Instrumentation Co., Ltd, 1 Shin-Nakahara-cho, Isogo-ku, Yokohama, Kanagawa (Japan); Miura, Yasuhiko; Ino, Tooru [Japan Nuclear Fuel Limited, 4-108, Aza Okitsuke, Oaza Obuchi, Rokkasho-Mura, Kamikita-gun, Aomori (Japan)

    2013-07-01

    Since 2008, the equipment for dismantling the used glass melter has been developed in High-level Liquid Waste (HLW) Vitrification Facility in the Japanese Rokkasho Reprocessing Plant (RRP). Due to the high radioactivity of the glass melter, the equipment requires a fully-remote operation in the vitrification cell. The remote fiber laser cutting system was adopted as one of the major pieces of equipment. An output power of fiber laser is typically higher than other types of laser and so can provide high-cutting performance. The fiber laser can cut thick stainless steel and Inconel, which are parts of the glass melter such as casings, electrodes and nozzles. As a result, it can make the whole of the dismantling work efficiently done for a shorter period. Various conditions of the cutting test have been evaluated in the process of developing the remote fiber cutting system. In addition, the expected remote operations of the power manipulator with the laser torch have been fully verified and optimized using 3D simulations. (authors)

  4. Glass fiber effect on mechanical properties of Eco-SCC

    Prasad M. L., V.; Loksesh, G.; Ramanjaneyulu, B.; Venkatesh, S.; Mousumi, K.

    2017-07-01

    Sustainable Construction encouraging the use of recycled materials and implies adoption of fewer natural resources in buildings and other infrastructure. In this paper Quarry Dust (QD) is used as partial replacement for River Sand (RS) to make Self Compacting Concrete (SCC) of grade M40. Glass fiber is used as strengthening material to the developed concrete. The present study mainly focused to develop Eco-SCC using QD. In this study it was found that, for developing Eco-SCC, what is the optimum dosage of replacement of QD in RS. Fresh properties of SCC are satisfying the EFNARC specifications and also target strength is achieved. Further it is concluded that, with the glass fiber addition there is an improvement in the split and flexural strength values.

  5. [A maxillary premolar reconstruction with a glass fiber reinforced post].

    Viţalariu, Anca Mihaela; Antohe, Magda; Bahrim, Delia; Tatarciuc, Monica

    2006-01-01

    This paper presents the case of a 37 years old female patient who needed a reconstruction of an endodontic treated' second maxillary premolar. The patient presented large areas of occlusal abrasion caused by bruxism, therefore the solution consisted of a reconstruction with a non-metallic post reinforced with glass fibers. In such cases, the excessive occlusal forces developed by bruxism can produce a radicular fracture if the tooth would be reconstructed with a rigid metallic post. The glass-fiber reinforced post has some important qualities, which render it more suitable in most clinical cases: it is easy to use; has the ability to bond with restorative resins; decreases the risk of tooth fracture and provides better esthetics.

  6. Effects of glass fibers on the properties of micro molded plastic parts

    Islam, Aminul; Hansen, Hans Nørgaard; Gasparin, Stefania

    2011-01-01

    Glass fibers are used to reinforce plastics and to improve their mechanical properties. But plastic filled with glass fibers is a concern for molding of micro scale plastic parts. The aim of this paper is to investigate the effects of glass fiber on the replication quality and mechanical properties...... of polymeric thin ribs. It investigates the effect of feature size and gate location on distribution of glass fibers inside the molded parts. The results from this work indicate that glass filled plastic materials have poor replication quality and nonhomogeneous mechanical properties due to the nonuniform...

  7. Depth Filters Containing Diatomite Achieve More Efficient Particle Retention than Filters Solely Containing Cellulose Fibers.

    Buyel, Johannes F; Gruchow, Hannah M; Fischer, Rainer

    2015-01-01

    The clarification of biological feed stocks during the production of biopharmaceutical proteins is challenging when large quantities of particles must be removed, e.g., when processing crude plant extracts. Single-use depth filters are often preferred for clarification because they are simple to integrate and have a good safety profile. However, the combination of filter layers must be optimized in terms of nominal retention ratings to account for the unique particle size distribution in each feed stock. We have recently shown that predictive models can facilitate filter screening and the selection of appropriate filter layers. Here we expand our previous study by testing several filters with different retention ratings. The filters typically contain diatomite to facilitate the removal of fine particles. However, diatomite can interfere with the recovery of large biopharmaceutical molecules such as virus-like particles and aggregated proteins. Therefore, we also tested filtration devices composed solely of cellulose fibers and cohesive resin. The capacities of both filter types varied from 10 to 50 L m(-2) when challenged with tobacco leaf extracts, but the filtrate turbidity was ~500-fold lower (~3.5 NTU) when diatomite filters were used. We also tested pre-coat filtration with dispersed diatomite, which achieved capacities of up to 120 L m(-2) with turbidities of ~100 NTU using bulk plant extracts, and in contrast to the other depth filters did not require an upstream bag filter. Single pre-coat filtration devices can thus replace combinations of bag and depth filters to simplify the processing of plant extracts, potentially saving on time, labor and consumables. The protein concentrations of TSP, DsRed and antibody 2G12 were not affected by pre-coat filtration, indicating its general applicability during the manufacture of plant-derived biopharmaceutical proteins.

  8. Depth filters containing diatomite achieve more efficient particle retention than filters solely containing cellulose fibers

    Johannes Felix Buyel

    2015-12-01

    Full Text Available The clarification of biological feed stocks during the production of biopharmaceutical proteins is challenging when large quantities of particles must be removed, e.g. when processing crude plant extracts. Single-use depth filters are often preferred for clarification because they are simple to integrate and have a good safety profile. However, the combination of filter layers must be optimized in terms of nominal retention ratings to account for the unique particle size distribution in each feed stock. We have recently shown that predictive models can facilitate filter screening and the selection of appropriate filter layers. Here we expand our previous study by testing several filters with different retention ratings. The filters typically contain diatomite to facilitate the removal of fine particles. However, diatomite can interfere with the recovery of large biopharmaceutical molecules such as virus-like particles and aggregated proteins. Therefore, we also tested filtration devices composed solely of cellulose fibers and cohesive resin. The capacities of both filter types varied from 10 to 50 L m-2 when challenged with tobacco leaf extracts, but the filtrate turbidity was ~500-fold lower (~3.5 NTU when diatomite filters were used. We also tested pre coat filtration with dispersed diatomite, which achieved capacities of up to 120 L m-2 with turbidities of ~100 NTU using bulk plant extracts, and in contrast to the other depth filters did not require an upstream bag filter. Single pre-coat filtration devices can thus replace combinations of bag and depth filters to simplify the processing of plant extracts, potentially saving on time, labor and consumables. The protein concentrations of TSP, DsRed and antibody 2G12 were not affected by pre-coat filtration, indicating its general applicability during the manufacture of plant-derived biopharmaceutical proteins.

  9. Real time sensing of structural glass fiber reinforced composites by using embedded PVA - carbon nanotube fibers

    Marioli-Riga Z.

    2010-06-01

    Full Text Available Polyvinyl alcohol - carbon nanotube (PVA-CNT fibers had been embedded to glass fiber reinforced polymers (GFRP for the structural health monitoring of the composite material. The addition of the conductive PVA-CNT fiber to the nonconductive GFRP material aimed to enhance its sensing ability by means of the electrical resistance measurement method. The test specimen’s response to mechanical load and the in situ PVA-CNT fiber’s electrical resistance measurements were correlated for sensing and damage monitoring purposes. The embedded PVA-CNT fiber worked as a sensor in GFRP coupons in tensile loadings. Sensing ability of the PVA-CNT fibers was also demonstrated on an integral composite structure. PVA-CNT fiber near the fracture area of the structure recorded very high values when essential damage occurred to the structure. A finite element model of the same structure was developed to predict axial strains at locations of the integral composite structure where the fibers were embedded. The predicted FEA strains were correlated with the experimental measurements from the PVA-CNT fibers. Calculated and experimental values were in good agreement, thus enabling PVA-CNT fibers to be used as strain sensors.

  10. Improvement of the piezoelectric properties of glass fiber-reinforced epoxy composites by poling treatment

    Oh, S M; Hwang, H Y

    2013-01-01

    Recently, a new non-destructive method has been proposed for damage monitoring of glass fiber-reinforced polymer composite materials using the piezoelectric characteristics of a polymeric matrix. Several studies of the piezoelectric properties of unidirectional glass fiber epoxy composites and damage monitoring of double-cantilever beams have supported the claim that the piezoelectric method is feasible and powerful enough to monitor the damage of glass fiber epoxy composites. Generally, conventional piezoelectric materials have higher piezoelectric characteristics through poling treatment. In this work, we investigated the change of the piezoelectric properties of glass fiber-reinforced epoxy composites before and after poling treatment. The piezoelectric constants (d 33 ) of glass fiber-reinforced epoxy composites increased by more than 400%. Also, x-ray diffraction tests revealed that poling treatment changed the degree of crystallinity of the epoxy matrix, and this led to the improvement of the piezoelectric characteristics of glass fiber-reinforced epoxy composites. (paper)

  11. Bonded carbon or ceramic fiber composite filter vent for radioactive waste

    Brassell, Gilbert W.; Brugger, Ronald P.

    1985-02-19

    Carbon bonded carbon fiber composites as well as ceramic or carbon bonded ceramic fiber composites are very useful as filters which can separate particulate matter from gas streams entraining the same. These filters have particular application to the filtering of radioactive particles, e.g., they can act as vents for containers of radioactive waste material.

  12. Fabrication of transparent superhydrophobic glass with fibered-silica network

    Zhang, Feng [College of Physics, Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006 (China); Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province & Key Lab of Modern Optical Technologies of Education Ministry of China, Soochow University, Suzhou 215006 (China); Shi, Zhenwu, E-mail: zwshi@suda.edu.cn [College of Physics, Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006 (China); Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province & Key Lab of Modern Optical Technologies of Education Ministry of China, Soochow University, Suzhou 215006 (China); Jiang, Yingjie; Xu, Chengyun; Wu, Zhuhui; Wang, Yanyan [College of Physics, Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006 (China); Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province & Key Lab of Modern Optical Technologies of Education Ministry of China, Soochow University, Suzhou 215006 (China); Peng, Changsi, E-mail: changsipeng@suda.edu.cn [College of Physics, Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006 (China); Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province & Key Lab of Modern Optical Technologies of Education Ministry of China, Soochow University, Suzhou 215006 (China)

    2017-06-15

    Highlights: • Superhydrophobic fibred-silica film with water contact angle of 166° and sliding angle of 1° was efficiently prepared using soot as template by CVD. • The film showed transmittance of 88% in visible range. • The superhydrophobic film possesses excellent mechanical robustness, chemical corrosion resistance, and thermal stability. • The superhydrophobic film showed outstanding self-cleaning behavior. - Abstract: In this paper, silica was deposited on the soot film pre-coated glass via chemical vapor deposition. Through calcination at 500 °C with the assistance of O{sub 2} airflow, the soot film was removed and a novel robust fibered-silica network film was then decorated onto the glass substrate. After modification with fluorosilane, the surface water contact angle (WCA) was 166° and sliding angle (SA) was 1° which behaves a good self-cleaning for the as-prepared glass. And its average transmittance was still over 88% in visible wavelength. Moreover, this fibered-silica coating showed a strong tolerance for heavy water droplets, acid/alkali corrosion, salt solution immersion and thermal treatment.

  13. Optimization of the contents of hollow glass microsphere and sodium hexametaphosphate for glass fiber vacuum insulation panel

    Li, C. D.; Chen, Z. F.; Zhou, J. M.

    2016-07-01

    In this paper, various additive amounts of hollow glass microspheres (HGMs) and sodium hexametaphosphate (SHMP) powders were blended with flame attenuated glass wool (FAGW) to form hybrid core materials (HCMs) through the wet method. Among them, the SHMP was dissolved in the glass fiber suspension and coated on the surface of glass fibers while the HGMs were insoluble in the glass fiber suspension and filled in the fiber-fiber pores. The average pore diameter of the FAGW/HGM HCMs was 8-11 μm which was near the same as that of flame attenuated glass fiber mats (FAGMs, i.e., 10.5 µm). The tensile strength of the SHMP coated FAGMs was enhanced from 160 N/m to 370 N/m when SHMP content increased from 0 wt.% to 0.2 wt.%. By contrast, the tensile strength of the FAGW/HGM HCMs decreased from 160 N/m to 40 N/m when HGM content increased from 0 wt.% to 50 wt.%. Both the FAGW/HGM HCMs and SHMP coated FAGMs were vacuumed completely to form vacuum insulation panels (VIPs). The results showed that both the addition of SHMP and HGM led a slight increase in the thermal conductivity of the corresponding VIPs. To obtain a high-quality VIP, the optimal SHMP content and HGM content in glass fiber suspension was 0.12-0.2 wt.% and 0 wt.%.

  14. Durability-Based Design Criteria for a Chopped-Glass-Fiber Automotive Structural Composite; TOPICAL

    Battiste, R.L.; Corum, J.M.; Ren, W.; Ruggles, M.B.

    1999-01-01

    This report provides recommended durability-based design criteria for a chopped-glass-fiber reinforced polymeric composite for automotive structural applications. The criteria closely follow the framework of an earlier criteria document for a continuous-strand-mat (CSM) glass-fiber reference composite. Together these design criteria demonstrate a framework that can be adapted for future random-glass-fiber composites for automotive structural applications

  15. Synthesis of nanocrystals in KNb(Ge,Si)O5 glasses and chemical etching of nanocrystallized glass fibers

    Enomoto, Itaru; Benino, Yasuhiko; Fujiwara, Takumi; Komatsu, Takayuki

    2006-01-01

    The nanocrystallization behavior of 25K 2 O-25Nb 2 O 5 -(50-x)GeO 2 -xSiO 2 glasses with x=0,25,and50 (i.e., KNb(Ge,Si)O 5 glasses) and the chemical etching behavior of transparent nanocrystallized glass fibers have been examined. All glasses show nanocrystallization, and the degree of transparency of the glasses studied depends on the heat treatment temperature. Transparent nanocrystallized glasses can be obtained if the glasses are heat treated at the first crystallization peak temperature. Transparent nanocrystallized glass fibers with a diameter of about 100μm in 25K 2 O-25Nb 2 O 5 -50GeO 2 are fabricated, and fibers with sharpened tips (e.g., the taper length is about 450μm and the tip angle is about 12 o ) are obtained using a meniscus chemical etching method, in which etching solutions of 10wt%-HF/hexane and 10M-NaOH/hexane are used. Although the tip (aperture size) has not a nanoscaled size, the present study suggests that KNb(Ge,Si)O 5 nanocrystallized glass fibers have a potential for new near-field optical fiber probes with high refractive indices of around n=1.8 and high dielectric constants of around ε=58 (1kHz, room temperature)

  16. Process monitoring of glass reinforced polypropylene laminates using fiber Bragg gratings

    Mulle, Matthieu; Wafai, Husam; Yudhanto, Arief; Lubineau, Gilles; Yaldiz, R.; Schijve, W.; Verghese, N.

    2015-01-01

    Hot-press molding of glass-fiber-reinforced polypropylene (GFPP) laminates was monitored using longitudinally and transversely embedded fiber Bragg gratings (FBGs) at different locations in unidirectional laminates. The optical sensors proved

  17. Characterization of Glass Fiber Separator Material for Lithium Batteries

    Subbarao, S.; Frank, H.

    1984-01-01

    Characterization studies were carried out on a glass fiber paper that is currently employed as a separator material for some LiSOCl2 primary cells. The material is of the non-woven type made from microfilaments of E-type glass and contains an ethyl acrylate binder. Results from extraction studies and tensile testing revealed that the binder content and tensile strength of the paper were significantly less than values specified by the manufacturer. Scanning electron micrographs revealed the presence of clusters of impurities many of which were high in iron content. Results of emission spectroscopy revealed high overall levels of iron and leaching, followed by atomic absorption measurements, revealed that essentially all of this iron is soluble in SOCl2.

  18. Glass fiber reinforced concrete for terrestrial photovoltaic arrays

    Maxwell, H.

    1979-01-01

    The use of glass-fiber-reinforced concrete (GRC) as a low-cost structural substrate for terrestrial solar cell arrays is discussed. The properties and fabrication of glass-reinforced concrete structures are considered, and a preliminary design for a laminated solar cell assembly built on a GRC substrate is presented. A total cost for such a photovoltaic module, composed of a Korad acrylic plastic film front cover, an aluminum foil back cover, an ethylene/vinyl acetate pottant/adhesive and a cotton fabric electrical isolator in addition to the GRC substrate, of $9.42/sq m is projected, which is less than the $11.00/sq m cost goal set by the Department of Energy. Preliminary evaluations are concluded to have shown the design capabilities and cost effectiveness of GRC; however, its potential for automated mass production has yet to be evaluated.

  19. Effect of Manufacturing Method to Tensile Properties of Hybrid Composite Reinforced by Natural (Agel Leaf Fiber) and Glass Fibers

    Nugroho, A.; Abdurohman, K.; Kusmono; Hestiawan, H.; Jamasri

    2018-04-01

    This paper described the effect of different type of manufacturing method to tensile properties of hybrid composite woven agel leaf fiber and glass fiber as an alternative of LSU structure material. The research was done by using 3 ply of woven agel leaf fiber (ALF) and 3 ply of glass fiber (wr200) while the matrix was using unsaturated polyester. Composite manufacturing method used hand lay-up and vacuum bagging. Tensile test conducted with Tensilon universal testing machine, specimen shape and size according to standard size ASTM D 638. Based on tensile test result showed that the tensile strength of agel leaf fiber composite with unsaturated polyester matrix is 54.5 MPa by hand lay-up and 84.6 MPa with vacuum bagging method. From result of tensile test, hybrid fiber agel composite and glass fiber with unsaturated polyester matrix have potential as LSU structure.

  20. Assessment of crushed-recycled glass as filter media for drinking water treatment

    Rutledge, S.O.; Fahie, C.; Gagnon, G.A.

    2002-01-01

    The objective of this project was to evaluate the performance of a pressure filter utilizing crushed glass as the filter media. The performance of the crushed glass filter was compared to that of a sand filter. The research was conducted in Orangedale, Nova Scotia, which is a small community of with a population of approximately 500. Orangedale is located on the south shore of Bras d'Or Lakes and feeds into Miller Pond, which serves as the source the of drinking water. The Orangedale treatment plant produces an average daily flow of 35 m3/d (6.4-gpm). The treatment plant consists of coagulation (sodium aluminate and polyaluminum chloride), flocculation, dissolved air flotation (DAF), disinfection with sodium hypochlorite and dual-media filtration with anthracite and sand. In general, the particle removal capabilities of the crushed glass filter were slightly poorer than that of a sand filter, as quantified in a field application in the community of Orangedale, Nova Scotia. It was found that the crushed glass used in this project had a higher angularity and slightly higher uniformity coefficient. During initial start-up the performance of the crushed glass filter was more variable and appeared to improve as the glass began to wear. After six-months of use the crushed glass filter was able to produce a very consistent filter effluent that was only slightly greater than the silica sand filter. After six-months of use, the sand filter achieved a 1.6 log-removal of particles with diameters greater than 2 μm; whereas the crushed glass filter achieved a 1.4 log removal for the similar particle size range. The observed removal performance was particularly encouraging given that the sand used had properties that were consistent with the standards set by the American Water Works Association. The crushed glass filter media was initially sieved and washed, but had no other pre-treatment preparation. Thus the application of crushed glass shows considerable promise as filter

  1. Properties of discontinuous S2-glass fiber-particulate-reinforced resin composites with two different fiber length distributions.

    Huang, Qiting; Garoushi, Sufyan; Lin, Zhengmei; He, Jingwei; Qin, Wei; Liu, Fang; Vallittu, Pekka Kalevi; Lassila, Lippo Veli Juhana

    2017-10-01

    To investigate the reinforcing efficiency and light curing properties of discontinuous S2-glass fiber-particulate reinforced resin composite and to examine length distribution of discontinuous S2-glass fibers after a mixing process into resin composite. Experimental S2-glass fiber-particulate reinforced resin composites were prepared by mixing 10wt% of discontinuous S2-glass fibers, which had been manually cut into two different lengths (1.5 and 3.0mm), with various weight ratios of dimethacrylate based resin matrix and silaned BaAlSiO 2 filler particulates. The resin composite made with 25wt% of UDMA/SR833s resin system and 75wt% of silaned BaAlSiO 2 filler particulates was used as control composite which had similar composition as the commonly used resin composites. Flexural strength (FS), flexural modulus (FM) and work of fracture (WOF) were measured. Fractured specimens were observed by scanning electron microscopy. Double bond conversion (DC) and fiber length distribution were also studied. Reinforcement of resin composites with discontinuous S2-glass fibers can significantly increase the FS, FM and WOF of resin composites over the control. The fibers from the mixed resin composites showed great variation in final fiber length. The mean aspect ratio of experimental composites containing 62.5wt% of particulate fillers and 10wt% of 1.5 or 3.0mm cutting S2-glass fibers was 70 and 132, respectively. No difference was found in DC between resin composites containing S2-glass fibers with two different cutting lengths. Discontinuous S2-glass fibers can effectively reinforce the particulate-filled resin composite and thus may be potential to manufacture resin composites for high-stress bearing application. Copyright © 2017. Published by Elsevier Ltd.

  2. Analysis of the strength and stiffness of timber beams reinforced with carbon fiber and glass fiber

    Juliano Fiorelli

    2003-06-01

    Full Text Available An experimental analysis of pinewood beams (Pinus caribea var hondurensis reinforced with glass and/or carbon fibers is discussed. The theoretical model employed to calculate the beam's bending strength takes into account the timber's ultimate limit states of tensile strength and failure by compression, considering a model of fragile elastic tension and plastic elastic compression. The validity of the theoretical model is confirmed by a comparison of the theoretical and experimental results, while the efficiency of the fiber reinforcement is corroborated by the increased strength and stiffness of the reinforced timber beams.

  3. The usage of carbon fiber reinforcement polymer and glass fiber reinforcement polymer for retrofit technology building

    Tarigan, Johannes; Meka, Randi; Nursyamsi

    2018-03-01

    Fiber Reinforcement Polymer has been used as a material technology since the 1970s in Europe. Fiber Reinforcement Polymer can reinforce the structure externally, and used in many types of buildings like beams, columns, and slabs. It has high tensile strength. Fiber Reinforcement Polymer also has high rigidity and strength. The profile of Fiber Reinforcement Polymer is thin and light, installation is simple to conduct. One of Fiber Reinforcement Polymer material is Carbon Fiber Reinforcement Polymer and Glass Fiber Reinforcement Polymer. These materials is tested when it is installed on concrete cylinders, to obtain the comparison of compressive strength CFRP and GFRP. The dimension of concrete is diameter of 15 cm and height of 30 cm. It is amounted to 15 and divided into three groups. The test is performed until it collapsed to obtain maximum load. The results of research using CFRP and GFRP have shown the significant enhancement in compressive strength. CFRP can increase the compressive strength of 26.89%, and GFRP of 14.89%. For the comparison of two materials, CFRP is more strengthening than GFRP regarding increasing compressive strength. The usage of CFRP and GFRP can increase the loading capacity.

  4. Faraday rotation influence factors in tellurite-based glass and fibers

    Chen, Qiuling; Wang, Qingwei [Henan University of Technology, School of Materials Science and Engineering, Zhengzhou, Henan (China); Wang, Hui; Chen, Qiuping [Politecnico di Torino, Department of Applied Science and Technology, Turin (Italy)

    2015-09-15

    The Faraday rotation influence factors in tellurite-based glass and fibers were studied by experiments and simulations. TeO{sub 2}-ZnO-Na{sub 2}O-BaO glass family was fabricated and characterized in terms of the thermal and magneto-optical properties. Two core-cladding pairs for two fibers were selected from fabricated glasses. The Verdet constants of the glasses and fibers were measured at different wavelengths using a homemade optical bench, and the Verdet constant of fiber was close to that of the bulk glass. The influence from external factors (wavelength, laser power and magnetic field) and internal factors (thermal expansion coefficient difference, refractive index and Verdet constant of core and cladding) on Faraday rotation in fibers was investigated and discussed, and the purpose of this study is to improve the Faraday rotation in tellurite fibers for MO device applications both from internal material property match and external parameter configuration in measurement. (orig.)

  5. Faraday rotation influence factors in tellurite-based glass and fibers

    Chen, Qiuling; Wang, Qingwei; Wang, Hui; Chen, Qiuping

    2015-01-01

    The Faraday rotation influence factors in tellurite-based glass and fibers were studied by experiments and simulations. TeO 2 -ZnO-Na 2 O-BaO glass family was fabricated and characterized in terms of the thermal and magneto-optical properties. Two core-cladding pairs for two fibers were selected from fabricated glasses. The Verdet constants of the glasses and fibers were measured at different wavelengths using a homemade optical bench, and the Verdet constant of fiber was close to that of the bulk glass. The influence from external factors (wavelength, laser power and magnetic field) and internal factors (thermal expansion coefficient difference, refractive index and Verdet constant of core and cladding) on Faraday rotation in fibers was investigated and discussed, and the purpose of this study is to improve the Faraday rotation in tellurite fibers for MO device applications both from internal material property match and external parameter configuration in measurement. (orig.)

  6. From Selenium- to Tellurium-Based Glass Optical Fibers for Infrared Spectroscopies

    Jacques Lucas

    2013-05-01

    Full Text Available Chalcogenide glasses are based on sulfur, selenium and tellurium elements, and have been studied for several decades regarding different applications. Among them, selenide glasses exhibit excellent infrared transmission in the 1 to 15 µm region. Due to their good thermo-mechanical properties, these glasses could be easily shaped into optical devices such as lenses and optical fibers. During the past decade of research, selenide glass fibers have been proved to be suitable for infrared sensing in an original spectroscopic method named Fiber Evanescent Wave Spectroscopy (FEWS. FEWS has provided very nice and promising results, for example for medical diagnosis. Then, some sophisticated fibers, also based on selenide glasses, were developed: rare-earth doped fibers and microstructured fibers. In parallel, the study of telluride glasses, which can have transmission up to 28 µm due to its atom heaviness, has been intensified thanks to the DARWIN mission led by the European Space Agency (ESA. The development of telluride glass fiber enables a successful observation of CO2 absorption band located around 15 µm. In this paper we review recent results obtained in the Glass and Ceramics Laboratory at Rennes on the development of selenide to telluride glass optical fibers, and their use for spectroscopy from the mid to the far infrared ranges.

  7. Flexural properties of polyethylene, glass and carbon fiber-reinforced resin composites for prosthetic frameworks.

    Maruo, Yukinori; Nishigawa, Goro; Irie, Masao; Yoshihara, Kumiko; Minagi, Shogo

    2015-01-01

    High flexural properties are needed for fixed partial denture or implant prosthesis to resist susceptibility to failures caused by occlusal overload. The aim of this investigation was to clarify the effects of four different kinds of fibers on the flexural properties of fiber-reinforced composites. Polyethylene fiber, glass fiber and two types of carbon fibers were used for reinforcement. Seven groups of specimens, 2 × 2 × 25 mm, were prepared (n = 10 per group). Four groups of resin composite specimens were reinforced with polyethylene, glass or one type of carbon fiber. The remaining three groups served as controls, with each group comprising one brand of resin composite without any fiber. After 24-h water storage in 37°C distilled water, the flexural properties of each specimen were examined with static three-point flexural test at a crosshead speed of 0.5 mm/min. Compared to the control without any fiber, glass and carbon fibers significantly increased the flexural strength (p glass fiber (p glass fibers (p > 0.05). Fibers could, therefore, improve the flexural properties of resin composite and carbon fibers in longitudinal form yielded the better effects for reinforcement.

  8. Alkali-resistant glass fiber reinforced high strength concrete in simulated aggressive environment

    Kwan, W.H.; Cheah, C.B.; Ramli, M.; Chang, K.Y.

    2018-01-01

    The durability of the alkali-resistant (AR) glass fiber reinforced concrete (GFRC) in three simulated aggresive environments, namely tropical climate, cyclic air and seawater and seawater immersion was investigated. Durability examinations include chloride diffusion, gas permeability, X-ray diffraction (XRD) and scanning electron microscopy examination (SEM). The fiber content is in the range of 0.6 % to 2.4 %. Results reveal that the specimen containing highest AR glass fiber content suffered severe strength loss in seawater environment and relatively milder strength loss under cyclic conditions. The permeability property was found to be more inferior with the increase in the fiber content of the concrete. This suggests that the AR glass fiber is not suitable for use as the fiber reinforcement in concrete is exposed to seawater. However, in both the tropical climate and cyclic wetting and drying, the incorporation of AR glass fiber prevents a drastic increase in permeability. [es

  9. Survey of life-cycle costs of glass-paper HEPA filters

    Moore, P.; Bergman, W.; Gilbert, H.

    1992-08-01

    We have conducted a survey of the major users of glass-paper HEPA filters in the DOE complex to ascertain the life cycle costs of these filters. Purchase price of the filters is only a minor portion of the costs; the major expenditures are incurred during the removal and disposal of contaminated filters. Through personal interviews, site visits and completion of questionnaires, we have determined the costs associated with the use of HEPA filters in the DOE complex. The total approximate life-cycle cost for a standard (2 in. x 2 in. x 1 in.) glass-paper HEPA filter is $3,000 for one considered low-level waste (LLW), $11,780 for transuranic (TRU) and $15,000 for high-level waste (HLW). The weighted-average cost for a standard HEPA filter in the complex is $4,753

  10. Evaluating the mechanical properties of E-Glass fiber/carbon fiber reinforced interpenetrating polymer networks

    G. Suresh

    2015-02-01

    Full Text Available A series of vinyl ester and polyurethane interpenetrating polymer networks were prepared by changing the component ratios of VER (Vinyl ester and PU (Polyurethane and the polymerization process was confirmed with Fourier Transform infrared spectroscopy. IPN (Inter Penetrating Polymer Network - VER/PU reinforced Glass and carbon fiber composite laminates were made using the Hand lay up technique. The Mechanical properties of the E-glass and carbon fiber specimens were compared from tests including Tensile, Compressive, Flexural, ILSS (Inter Laminar Shear Strength, Impact & Head Deflection Test (HDT. The IPN Reinforced Carbon fiber specimen showed better results in all the tests than E-Glass fibre reinforced IPN laminate with same thickness of the specimen, according to ASTM standards. It was found that the combination of 60%VER and 40%PU IPN exhibits better impact strength and maximum elongation at break, but at the slight expense of mechanical properties such as tensile, compressive, flexural, ILSS properties. The morphology of the unreinforced and reinforced composites was analyzed with help of scanning electron microscopy.

  11. A Comparative Study of Natural Fiber and Glass Fiber Fabrics Properties with Metal or Oxide Coatings

    Lusis, Andrej; Pentjuss, Evalds; Bajars, Gunars; Sidorovicha, Uljana; Strazds, Guntis

    2015-01-01

    Rapidly growing global demand for technical textiles industries is stimulated to develop new materials based on hybrid materials (yarns, fabrics) made from natural and glass fibres. The influence of moisture on the electrical properties of metal and metal oxide coated bast (flax, hemp) fibre and glass fibre fabrics are studied by electrical impedance spectroscopy and thermogravimetry. The bast fibre and glass fiber fabrics are characterized with electrical sheet resistance. The method for description of electrical sheet resistance of the metal and metal oxide coated technical textile is discussed. The method can be used by designers to estimate the influence of moisture on technical data of new metal coated hybrid technical textile materials and products

  12. Microwave-assisted extraction of metal elements from glass fibrous filters for aerosol sampling

    Li Dong-Mei; Zhang Li-Xing; Wang Xu-Hui; Liu Long-Bo

    2003-01-01

    Atmospheric aerosols are generally collected on filters according to the International Monitoring System (IMS) designed in the Comprehensive Nuclear-Test-Ban Treaty (CTBT). More information could be revealed when the filter sample is pretreated rather than measured directly by γ-ray spectrometer. Microwave-assisted extraction (MAE) is a suitable method that gives higher recoveries of elements from glass fibrous filters under different conditions. The results indicate that the MAE is a highly efficient and robust method for the treatment of glass fibrous filter samples. The recoveries of potential fission products from glass fibrous filter samples by microwave-assisted extraction meet the efficiency of the extraction by both aqua regia and 2% HCl. (author)

  13. Prevention of cancer risk of workers of glass fibers manufacture

    G.F. Mukhammadieva

    2016-09-01

    Full Text Available In the process of producing of continuous glass fiber workers are exposed to complex impact of carcinogenic chemicals released into the air of the working area (including formaldehyde, epichlorohydrin, ethane acids, aerosol of mineral oil. The penetrating effect of harmful substances through the skin is enhanced by the fine glass dust, which has a traumatic and irritating effect. Aggravating factors of the impact of lubricants on the body of the operators is the increased temperature and the excess of heat radiation. A risk factor is also the unfavorable climate of the workplace. Among the professional patients (71 person of 170 examined employees most of persons aged 50–59 years. The average age of the patients at the time of detection of hyperkeratosis was 51,9 ± 0,9 years, skin cancer – 57,3 ± 1,7 years. Professional skin neoplasms were diagnosed mainly in workers who have been working for more than 10 years (average period of 12.6 ± 2.4 years. The period of transformation of limited hyperkeratosis to the skin cancer was on average 5–8 years. It was found that the molecular-genetic factors predisposing to the development of professional skin lesions are polymorphic variants of the gene suppressor of tumor growth TP53 (Ex4 + 119G>C, IVS3 16 bp Del/Ins and IVS6+62A>G. It has been shown that the development of preventive measures aimed at reducing the risk of occupational diseases is relevant and should include the interaction of administration, engineering and technical staff of the enterprise, labor protection service, Rospotrebnadzor specialists, doctors specialized in occupational diseases and the workers themselves. The complex of measures of primary and secondary prevention of health problems is suggested. The necessity of including the continuous glass fiber production to the list of carcinogen production processes, presented in national normative documents.

  14. Ceramic fiber-reinforced monoclinic celsian phase glass-ceramic matrix composite material

    Bansal, Narottam P. (Inventor); Dicarlo, James A. (Inventor)

    1994-01-01

    A hyridopolysilazane-derived ceramic fiber reinforced monoclinic celsian phase barium aluminum silicate glass-ceramic matrix composite material is prepared by ball-milling an aqueous slurry of BAS glass powder and fine monoclinic celsian seeds. The fibers improve the mechanical strength and fracture toughness and with the matrix provide superior dielectric properties.

  15. Fatigue crack initiation in hybrid boron/glass/aluminum fiber metal laminates

    Chang, P.-Y.; Yeh, P.-C.; Yang, J.-M.

    2008-01-01

    The fatigue crack initiation behavior of a high modulus and hybrid boron/glass/aluminum fiber/metal laminate (FML) was investigated experimentally and analytically. Two types of hybrid boron/glass/aluminum FMLs were fabricated and studied, which consisted of aluminum alloy sheets as the metal layers and a mixture of boron fibers and glass fibers as the composite layers. For the first type, the boron fiber/prepreg and the glass fiber/prepreg were used separately in the composite layers, and for the second type, the boron fibers and the glass fibers were mingled together to form a hybrid boron/glass/prepreg composite layer. These hybrid FMLs were consolidated using an autoclave curing process. The incorporation of the boron fibers improved the Young's modulus of the composite layer in FMLs, which in turn, would improve the fatigue crack initiation life of the Al sheet. The experimental results clearly showed that the fatigue crack initiation lives for both types of hybrid boron/glass/aluminum FMLs were superior to the monolithic aluminum alloy under the same loading condition. An analytical approach was proposed to calculate the fatigue crack initiation lives of hybrid boron/glass/aluminum FMLs based on the classical laminate theory and the small-crack theory. A good correlation was obtained between the predictions and the experimental results

  16. Static and Dynamic Behavior of High Modulus Hybrid Boron/Glass/Aluminum Fiber Metal Laminates

    Yeh, Po-Ching

    2011-12-01

    This dissertation presents the investigation of a newly developed hybrid fiber metal laminates (FMLs) which contains commingled boron fibers, glass fibers, and 2024-T3 aluminum sheets. Two types of hybrid boron/glass/aluminum FMLs are developed. The first, type I hybrid FMLs, contained a layer of boron fiber prepreg in between two layers of S2-glass fiber prepreg, sandwiched by two aluminum alloy 2024-T3 sheets. The second, type II hybrid FMLs, contained three layer of commingled hybrid boron/glass fiber prepreg layers, sandwiched by two aluminum alloy 2024-T3 sheets. The mechanical behavior and deformation characteristics including blunt notch strength, bearing strength and fatigue behavior of these two types of hybrid boron/glass/aluminum FMLs were investigated. Compared to traditional S2-glass fiber reinforced aluminum laminates (GLARE), the newly developed hybrid boron/glass/aluminum fiber metal laminates possess high modulus, high yielding stress, and good blunt notch properties. From the bearing test result, the hybrid boron/glass/aluminum fiber metal laminates showed outstanding bearing strength. The high fiber volume fraction of boron fibers in type II laminates lead to a higher bearing strength compared to both type I laminates and traditional GLARE. Both types of hybrid FMLs have improved fatigue crack initiation lives and excellent fatigue crack propagation resistance compared to traditional GLARE. The incorporation of the boron fibers improved the Young's modulus of the composite layer in FMLs, which in turn, improved the fatigue crack initiation life and crack propagation rates of the aluminum sheets. Moreover, a finite element model was established to predict and verify the properties of hybrid boron/glass/aluminum FMLs. The simulated results showed good agreement with the experimental results.

  17. Impact properties of aluminium - glass fiber reinforced plastics sandwich panels

    Mathivanan Periasamy

    2012-06-01

    Full Text Available Aluminium - glass fiber reinforced plastics (GFRP sandwich panels are hybrid laminates consisting of GFRP bonded with thin aluminum sheets on either side. Such sandwich materials are increasingly used in airplane and automobile structures. Laminates with varying aluminium thickness fractions, fiber volume fractions and orientation in the layers of GFRP were fabricated by hand lay up method and evaluated for their impact performance by conducting drop weight tests under low velocity impacts. The impact energy required for initiating a crack in the outer aluminium layer as well as the energy required for perforation was recorded. The impact load-time history was also recorded to understand the failure behavior. The damage depth and the damage area were measured to evaluate the impact resistance. Optical photography and scanning electron micrographs were taken to visualize the crack and the damage zone. The bidirectional cross-ply hybrid laminate (CPHL has been found to exhibit better impact performance and damage resistance than the unidirectional hybrid laminate (UDHL. Increase in aluminium thickness fraction (Al tf and fiber volume fraction (Vf resulted in an increase in the impact energy required for cracking and perforation. On an overall basis, the sandwich panels exhibited better impact performance than the monolithic aluminium.

  18. Monotonic and cyclic responses of impact polypropylene and continuous glass fiber-reinforced impact polypropylene composites at different strain rates

    Yudhanto, Arief; Lubineau, Gilles; Wafai, Husam; Mulle, Matthieu; Pulungan, Ditho Ardiansyah; Yaldiz, R.; Verghese, N.

    2016-01-01

    Impact copolymer polypropylene (IPP), a blend of isotactic polypropylene and ethylene-propylene rubber, and its continuous glass fiber composite form (glass fiber-reinforced impact polypropylene, GFIPP) are promising materials for impact

  19. Energy absorption at high strain rate of glass fiber reinforced mortars

    Fenu Luigi

    2015-01-01

    Full Text Available In this paper, the dynamic behaviour of cement mortars reinforced with glass fibers was studied. The influence of the addition of glass fibers on energy absorption and tensile strength at high strain-rate was investigated. Static tests in compression, in tension and in bending were first performed. Dynamic tests by means of a Modified Hopkinson Bar were then carried out in order to investigate how glass fibers affected energy absorption and tensile strength at high strain-rate of the fiber reinforced mortar. The Dynamic Increase Factor (DIF was finally evaluated.

  20. All-Glass Fiber Amplifier Pumped by Ultra-High Brightness Pumps

    2016-02-15

    coating can exceed its long-term damage threshold. Such a concern obviously does not apply to a fiber with gold protective coating [14]. Thus in... coated triple-clad fibers, we are developing triple-clad Yb fiber with gold coating for improved thermal management. 2.1 Pump laser The two...is still an acrylate coating outside the glass clad for fiber handling and protection . Calculation shows that the temperature of the fiber acrylate

  1. Scalable air cathode microbial fuel cells using glass fiber separators, plastic mesh supporters, and graphite fiber brush anodes

    Zhang, Xiaoyuan; Cheng, Shaoan; Liang, Peng; Huang, Xia; Logan, Bruce E.

    2011-01-01

    The combined use of brush anodes and glass fiber (GF1) separators, and plastic mesh supporters were used here for the first time to create a scalable microbial fuel cell architecture. Separators prevented short circuiting of closely

  2. Pr3 + -doped GeSx-based glasses for fiber amplifiers at 1.3 µm

    Simons, D. R.; Faber, A. J.; de Waal, H.

    1995-03-01

    The photoluminescence properties of Pr3+ -doped GeS x -based glasses are studied and compared with those of other sulfide and fluoride glasses. The possibility of highly pump-power-efficient fiber amplifiers based on these GeSx-containing glasses in the telecommunications window at 1.3 mu m is discussed.

  3. Pr3+-doped GeSx-based glasses for fiber amplifiers at 1.3 mm

    Simons, D.R.; Faber, A.J.; Waal, de H.

    1995-01-01

    The luminescence of Pr3+-doped GeSx-based glasses were studied and compared with those of other sulfide and fluoride glasses. The possibility of highly pump-power-efficient fiber amplifiers based on these GeSx-contg. glasses in the telecommunications window at 1.3 mm is discussed. [on SciFinder (R)

  4. Comparison between three glass fiber post cementation techniques.

    Migliau, Guido; Piccoli, Luca; Di Carlo, Stefano; Pompa, Giorgio; Besharat, Laith Konstantinos; Dolci, Marco

    2017-01-01

    The aim of this experimental study was to compare the traditional cement systems with those of the latest generation, to assess if indeed these could represent of viable substitutes in the cementation of indirect restorations, and in the specific case of endodontic posts. The assessment of the validity of the cementing methods was performed according to the test of the push-out, conducted on sections obtained from the roots of treated teeth. The samples were divided into three groups. Group A (10 samples): etching for 30 seconds with 37% orthophosphoric acid (Superlux-Thixo-etch-DMG) combined with a dual-curing adhesive system (LuxaBond-Total Etch-DMG), dual-cured resin-composite cement (LuxaCore-DMG) and glass fiber posts (LuxaPost-DMG). Group B (10 samples): self-adhesive resin cement (Breeze-Pentron Clinical) and glass fiber posts (LuxaPost-DMG). Group C (10 samples): 3 steps light-curing, self-etching, self-conditioning bonding agent (Contax-Total-etch-DMG), dual-cured resin-composite cement (LuxaCore-DMG) and glass fiber posts (LuxaPost-DMG). The survey was conducted by examining the breaking resistance of the post-cement-tooth complex, subjected to a mechanical force. Statistical analysis was performed using SPSS Inc. ver. 13.0, Chicago, IL, USA. Group A values of bond strenth ranged from a minimum of 10.14 Mpa to a maximum value of 14.73 Mpa with a mean value of 12.58 Mpa. In Group B the highest value of bond strength was 6.54 Mpa and the minimum 5.55 Mpa. The mean value of the bond strength for the entire group was 6.58 Mpa. In Group C the highest bond strength was 6.59 Mpa whereas the lowest bond strength was 4.84 Mpa. Mean value of the bond strength of Group C was calculated at 5.7 Mpa. Etching with orthophosphoric acid combined with a dual-curing adhesive system and a dual-cured resin-composite cement was the technique that guaranteed the highest bond strength. Lowest bond strength values were obtained when dual self-adhesive cement was used.

  5. Dynamic Mechanical and Thermal Properties of Bagasse/Glass Fiber/Polypropylene Hybrid Composites

    Mehdi Roohani

    2016-06-01

    Full Text Available This work aims to evaluate the thermal and dynamic mechanical properties of bagasse/glass fiber/polypropylene hybrid composites. Composites were prepared by the melt compounding method and their properties were characterized by differential scanning calorimetry (DSC and dynamic mechanical analysis (DMA. DSC results found that with incorporation of bagasse and glass fiber the melting temperature (Tm and the crystallisation temperature (Tc shift to higher temperatures and the degree of crystallinity (Xc increase. These findings suggest that the fibers played the role of a nucleating agent in composites. Dynamic mechanical analysis indicated that by the incorporation of bagasse and glass fiber into polypropylene, the storage modulus ( and the loss modulus ( increase whereas the mechanical loss factor (tanδ decrease. To assess the effect of reinforcement with increasing temperature, the effectiveness coefficient C was calculated at different temperature ranges and revealed that, at the elevated temperatures, improvement of mechanical properties due to the presence of fibers was more noticeable. The fiber-matrix adhesion efficiency determined by calculating of adhesion factor A in terms of the relative damping of the composite (tan δc and the polymer (tan δpand volume fraction of the fibers (Фf. Calculated adhesion factor A values indicated that by adding glass fiber to bagasse/polypropylene system, the fiber-matrix adhesion improve. Hybrid composite containing 25% bagasse and 15% glass fiber showed better fiber-matrix adhesion.

  6. Novel tunable optical filter employing a fiber loop mirror for synthesis applications in WDM

    Vázquez García, María Carmen; Vargas Palma, Salvador Elías; Sánchez-Pena, José Manuel

    2001-01-01

    A novel optical filter employing a fiber loop mirror within an amplified ring resonator is presented. The fiber loop mirror allows tuning by changing the coupling factor of a coupler. The device can be used as a building block to synthesize optical filters, as previously reported, saving components. Publicado

  7. In vitro cytotoxicity of Manville Code 100 glass fibers: Effect of fiber length on human alveolar macrophages

    Jones William

    2006-03-01

    Full Text Available Abstract Background Synthetic vitreous fibers (SVFs are inorganic noncrystalline materials widely used in residential and industrial settings for insulation, filtration, and reinforcement purposes. SVFs conventionally include three major categories: fibrous glass, rock/slag/stone (mineral wool, and ceramic fibers. Previous in vitro studies from our laboratory demonstrated length-dependent cytotoxic effects of glass fibers on rat alveolar macrophages which were possibly associated with incomplete phagocytosis of fibers ≥ 17 μm in length. The purpose of this study was to examine the influence of fiber length on primary human alveolar macrophages, which are larger in diameter than rat macrophages, using length-classified Manville Code 100 glass fibers (8, 10, 16, and 20 μm. It was hypothesized that complete engulfment of fibers by human alveolar macrophages could decrease fiber cytotoxicity; i.e. shorter fibers that can be completely engulfed might not be as cytotoxic as longer fibers. Human alveolar macrophages, obtained by segmental bronchoalveolar lavage of healthy, non-smoking volunteers, were treated with three different concentrations (determined by fiber number of the sized fibers in vitro. Cytotoxicity was assessed by monitoring cytosolic lactate dehydrogenase release and loss of function as indicated by a decrease in zymosan-stimulated chemiluminescence. Results Microscopic analysis indicated that human alveolar macrophages completely engulfed glass fibers of the 20 μm length. All fiber length fractions tested exhibited equal cytotoxicity on a per fiber basis, i.e. increasing lactate dehydrogenase and decreasing chemiluminescence in the same concentration-dependent fashion. Conclusion The data suggest that due to the larger diameter of human alveolar macrophages, compared to rat alveolar macrophages, complete phagocytosis of longer fibers can occur with the human cells. Neither incomplete phagocytosis nor length-dependent toxicity was

  8. Influence of Hybridizing Flax and Hemp-Agave Fibers with Glass Fiber as Reinforcement in a Polyurethane Composite

    Pankaj Pandey

    2016-05-01

    Full Text Available In this study, six combinations of flax, hemp, and glass fiber were investigated for a hybrid reinforcement system in a polyurethane (PU composite. The natural fibers were combined with glass fibers in a PU composite in order to achieve a better mechanical reinforcement in the composite material. The effect of fiber hybridization in PU composites was evaluated through physical and mechanical properties such as water absorption (WA, specific gravity (SG, coefficient of linear thermal expansion (CLTE, flexural and compression properties, and hardness. The mechanical properties of hybridized samples showed mixed trends compared to the unhybridized samples, but hybridization with glass fiber reduced water absorption by 37% and 43% for flax and hemp-agave PU composites respectively.

  9. First application of hollow fiber filter for PWR condensate polishing

    Tsuda, S.; Otoha, K.; Takiguchi, H.

    2002-01-01

    In Tsuruga Unit-2 (PWR 1160 MWe commenced commercial operation in 1987), current procedure for secondary system clean-up before start-up had prolonged outage time and had consumed a huge amount of de-ionized (DI) water. In addition, iron oxide in condensate had accelerated the degradation of condensate demineralizer (CD) resin. The corrosion product of iron could also influence the secondary side corrosion of steam generator (SG) tubing if it intruded into SG through CD. To solve these problems, Japan Atomic Power Company (JAPC) decided to introduce hollow fiber filter (HFF) type condensate filter into Tsuruga-2, as the first application to PWR in the world. Because of retro-fitted HFF in Tsuruga Unit-2, limitations for installation space and flow resistance in condensate system and cost reduction required new design for compact and low differential pressure system and for long life filter module. JAPC and ORGANO assessed methodologies to achieve these goals. An advanced HFF system, including a newly developed compact HFF module design, was installed at Tsuruga Unit-2 in 1997 based on the assessment. During the 5 years since the installation, the HFF system has provided excellent crud removal that enables to shorten the outage period and to reduce DI water consumption drastically. Stable differential pressure (dP) trend of the HFF system indicates an expected module life of more than 7 years, with backwash cleaning required only 2 or 3 times per year. In addition to providing the expected operating cost reduction and improved SG tube integrity, numerous additional benefits have resulted from the retrofit. (authors)

  10. The effect of silanated and impregnated fiber on the tensile strength of E-glass fiber reinforced composite retainer

    Niswati Fathmah Rosyida

    2015-12-01

    Full Text Available Background: Fiber reinforced composite (FRC is can be used in dentistry as an orthodontic retainer. FRC  still has a limitations because of to  a weak bonding between fibers and matrix. Purpose: This research was aimed to evaluate the effect of silane as coupling agent and fiber impregnation on the tensile strength of E-glass FRC. Methods: The samples of this research were classified into two groups each of which consisted of three subgroups, namely the impregnated fiber group (original, 1x addition of silane, 2x addition of silane and the non-impregnated fiber group (original, 1x addition of silane, 2x addition of silane. The tensile strength was measured by a universal testing machine. The averages of the tensile strength in all groups then were compared by using Kruskal Wallis and Mann Whitney post hoc tests. Results: The averages of the tensile strength (MPa in the impregnated fiber group can be known as follow; original impregnated fiber (26.60±0.51, 1x addition of silane (43.38±4.42, and 2x addition of silane (36.22±7.23. The averages of tensile strength (MPa in the non-impregnated fiber group can also be known as follow; original non-impregnated fiber (29.38±1.08, 1x addition of silane (29.38±1.08, 2x addition of silane (12.48±2.37. Kruskal Wallis test showed that there was a significant difference between the impregnated fiber group and the non-impregnated fiber group (p<0.05. Based on the results of post hoc test, it is also known that the addition of silane in the impregnated fiber group had a significant effect on the increasing of the tensile strength of E-glass FRC (p<0.05, while the addition of silane in the non-impregnated fiber group had a significant effect on the decreasing of the tensile strength of E-glass FRC. Conclusion: It can be concluded that the addition of silane in the non-silanated fiber group can increase the tensile strength of E-glass FRC, but the addition of silane in the silanated fiber group can

  11. Commercial Production of Heavy Metal Fluoride Glass Fiber in Space

    Tucker, Dennis S.; Workman, Gary L.; Smith, Guy A.

    1998-01-01

    International Space Station Alpha (ISSA) will provide a platform not only for materials research but also a possible means to produce products in space which cannot be easily produced on the ground. Some products may even be superior to those now produced in unit gravity due to the lack of gravity induced convection effects. Our research with ZrF4-BaF2-LaF3-AlF3-NaF (ZBLAN glass) has shown that gravity does indeed play a major role in the crystallization behavior of this material. At the present time ZBLAN is being produced on earth in fiber optic form for use in surgical lasers and fiber optic lasers among other applications. High attenuation coefficients, however, have kept this material from being used in other applications such as long haul data transmission links. The high attenuation coefficients are due to impurities which can be removed through improved processing techniques and crystals which can only be removed or prevented from forming by processing in a reduced gravity environment.

  12. Physicochemical properties of discontinuous S2-glass fiber reinforced resin composite.

    Huang, Qiting; Qin, Wei; Garoushi, Sufyan; He, Jingwei; Lin, Zhengmei; Liu, Fang; Vallittu, Pekka K; Lassila, Lippo V J

    2018-01-30

    The objective of this study was to investigate several physicochemical properties of an experimental discontinuous S2-glass fiber-reinforced resin composite. The experimental composite was prepared by mixing 10 wt% of discontinuous S2-glass fibers with 27.5 wt% of resin matrix and 62.5 wt% of particulate fillers. Flexural strength (FS) and modulus (FM), fracture toughness (FT), work of fracture (WOF), double bond conversion (DC), Vickers hardness, volume shrinkage (VS) and fiber length distribution were determined. These were compared with two commercial resin composites. The experimental composite showed the highest FS, WOF and FT compared with two control composites. The DC of the experimental composite was comparable with controls. No significant difference was observed in VS between the three tested composites. The use of discontinuous glass fiber fillers with polymer matrix and particulate fillers yielded improved physical properties and substantial improvement was associated with the use of S2-glass fiber.

  13. Characterization of glass filter micromodels used for polymer EOR flooding experiments

    Foedisch, H.; Wegner, J.; Hincapie-Reina, R.; Ganzer, L. [Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany). ITE

    2013-08-01

    This work is conducted as part of the research project DGMK 746 - ''Experimental and Numerical Analysis of Polymer Flooding Processes Using Micromodels - From Pore Scale to Continuum Scale''. The industry standard to assess polymer flood performance is through flooding experiments with cores or plugs. A complement to flooding experiments in cores is represented by micromodels such as glass filters, which resemble real porous media through their porous structures. In this way, an almost unlimited number of equivalent samples can be produced. Moreover, compared to cores the micromodels enable visual access to the flooding process enabling a detailed process description. The sintered glass filters used in this work represent one way to make displacement processes inside artificial structures visible. However, challenges exist to transfer the results obtained from models composed of glass to real plugs or rock sections. Therefore, this study focuses on the comparison of glass filter micromodels and real rock samples composed of Bentheimer sandstone. We determine water permeability and oil-water relative permeability endpoints with flooding experiments, compare capillary pressure functions of the glass models obtained from mercury porosimetry analysis with results from Bentheimer sandstone, and characterize the glass filter with respect of connate water saturation using NMR-spectroscopy and porosity obtained from pycnometer measurements. (orig.)

  14. In-plane spectroscopy with optical fibers and liquid-filled APEX™ glass microcuvettes

    Gaillard, William R; Tantawi, Khalid Hasan; Williams, John D; Waddell, Emanuel; Fedorov, Vladimir

    2013-01-01

    Chemical etching and laser drilling of microstructural glass results in opaque or translucent sidewalls, limiting the optical analysis of glass microfluidic devices to top down or non-planar topologies. These non-planar observation topologies prevent each layer of a multilayered device from being independently optically addressed. However, novel photosensitive glass processing techniques in APEX™ have resulted in microfabricated glass structures with transparent sidewalls. Toward the goal of a transparent multilayered glass microfluidic device, this study demonstrates the ability to perform spectroscopy with optical fibers and microcuvettes fabricated in photosensitive APEX™ glass. (technical note)

  15. Investigating the Properties of Asphalt Concrete Containing Glass Fibers and Nanoclay

    Hasan Taherkhani

    2016-06-01

    Full Text Available The performance of asphaltic pavements during their service life is highly dependent on the mechanical properties of the asphaltic layers. Therefore, in order to extend their service life, scientists and engineers are constantly trying to improve the mechanical properties of the asphaltic mixtures. One common method of improving the performance of asphaltic mixtures is using different types of additives. This research investigated the effects of reinforcement by randomly distributed glass fibers and the simultaneous addition of nanoclayon some engineering properties of asphalt concrete have been investigated. The properties of a typical asphalt concrete reinforced by different percentages of glass fibers were compared with those containing both the fibers and nanoclay. Engineering properties, including Marshall stability, flow, Marshall quotient, volumetric properties and indirect tensile strength were studied. Glass fibers were used in different percentages of 0.2, 0.4 and 0.6% (by weight of total mixture, and nanoclay was used in 2, 4 and 6% (by the weight of bitumen. It was found that the addition of fibers proved to be more effective than the nanoclay in increasing the indirect tensile strength. However, nanoclay improved the resistance of the mixture against permanent deformation better than the glass fibers. The results also showed that the mixture reinforced by 0.2% of glass fiber and containing 6% nanoclay possessed the highest Marshall quotient, and the mixture containing 0.6% glass fibers and 2% nanoclay possessedthe highest indirect tensile strength.

  16. Monitoring Poisson's ratio of glass fiber reinforced composites as damage index using biaxial Fiber Bragg Grating sensors

    Yılmaz, Çağatay; Yilmaz, Cagatay; Akalın, Çağdaş; Akalin, Cagdas; Kocaman, Esat Selim; Suleman, A.; Yıldız, Mehmet; Yildiz, Mehmet

    2016-01-01

    Damage accumulation in Glass Fiber Reinforced Polymer (GFRP) composites is monitored based on Poisson's ratio measurements for three different fiber stacking sequences subjected to both quasi-static and quasi-static cyclic tensile loadings. The sensor systems utilized include a dual-extensometer, a biaxial strain gage and a novel embedded-biaxial Fiber Bragg Grating (FBG) sensor. These sensors are used concurrently to measure biaxial strain whereby the evolution of Poisson's ratio as a functi...

  17. Studies on fabrication of glass fiber reinforced composites using polymer blends

    Patel, R. H.; Kachhia, P. H.; Patel, S. N.; Rathod, S. T.; Valand, J. K.

    2018-05-01

    Glass fiber reinforced PVC/NBR composites have been fabricated via hot compression moulding process. PVC is brittle in nature and thus lower thermal stability. Therefore, to improve the toughness of PVC, NBR was incorporated in certain proportions. As both are polar and thus they are compatible. To improve the strength property further, these blends were used to fabricate glass fiber reinforced composites. SEM micrograph shows good wettability of the blend with glass fibers resulting in proper bonding which increase the strength of the composites.

  18. Spectral shaping of an all-fiber torsional acousto-optic tunable filter.

    Ko, Jeakwon; Lee, Kwang Jo; Kim, Byoung Yoon

    2014-12-20

    Spectral shaping of an all-fiber torsional acousto-optic (AO) tunable filter is studied. The technique is based on the axial modulation of AO coupling strength along a highly birefringent optical fiber, which is achieved by tailoring the outer diameter of the fiber along its propagation axis. Two kinds of filter spectral shaping schemes-Gaussian apodization and matched filtering with triple resonance peaks-are proposed and numerically investigated under realistic experimental conditions: at the 50-cm-long AO interaction length of the fiber and at half of the original fiber diameter as the minimum thickness of the tailored fiber section. The results show that the highest peak of sidelobe spectra in filter transmission is suppressed from 11.64% to 0.54% via Gaussian modulation of the AO coupling coefficient (κ). Matched filtering with triple resonance peaks operating with a single radio frequency signal is also achieved by cosine modulation of κ, of which the modulation period determines the spectral distance between two satellite peaks located in both wings of the main resonance peak. The splitting of two satellite peaks in the filter spectra reaches 48.2 nm while the modulation period varies from 7.7 to 50 cm. The overall peak power of two satellite resonances is calculated to be 22% of the main resonance power. The results confirm the validity and practicality of our approach, and we predict robust and stable operation of the designed all-fiber torsional AO filters.

  19. NUMERICAL ESTIMATION OF EFFECTIVE ELASTIC MODULI OF SYNTACTIC FOAMS REINFORCED BY SHORT GLASS FIBERS

    Wei Yu

    2016-03-01

    Full Text Available The mechanical properties of hollow glass microsphere/epoxy resin syntactic foams reinforced by short glass fibers are studied using representative volume elements. Both the glass fibers and the hollow glass microspheres exhibit random arrangement in the epoxy resin. The volume fraction and wall thickness of hollow glass microspheres and the volume fraction of glass fibers are considered as parameters. It is observed that the elastic modulus values of syntactic foams decrease with the increase of microsphere volume fraction when the microsphere relative wall thickness is lower. However, it increases with the increase of microsphere volume fraction when the relative wall thickness exceeds a critical value. The elastic modulus value goes through a maximum when the relative wall thickness is around 0.06 at 25 % volume fraction of microspheres. The addition of glass fibers reduces the critical wall thickness values of the microspheres and increases the mechanical properties of the composites. The highest stress lies on the equatorial plane perpendicular to the loading direction. Adding fibers reduces the large stress distribution areas on the microspheres, and the fibers aligned with the loading direction play an important load-bearing role.

  20. Durability Characteristics Analysis of Plastic Worm Wheel with Glass Fiber Reinforced Polyamide.

    Kim, Gun-Hee; Lee, Jeong-Won; Seo, Tae-Il

    2013-05-10

    Plastic worm wheel is widely used in the vehicle manufacturing field because it is favorable for weight lightening, vibration and noise reduction, as well as corrosion resistance. However, it is very difficult for general plastics to secure the mechanical properties that are required for vehicle gears. If the plastic resin is reinforced by glass fiber in the fabrication process of plastic worm wheel, it is possible to achieve the mechanical properties of metallic material levels. In this study, the mechanical characteristic analysis of the glass-reinforced plastic worm wheel, according to the contents of glass fiber, is performed by analytic and experimental methods. In the case of the glass fiber-reinforced resin, the orientation and contents of glass fibers can influence the mechanical properties. For the characteristic prediction of plastic worm wheel, computer-aided engineering (CAE) analysis processes such as structural and injection molding analysis were executed with the polyamide resin reinforcement glass fiber (25 wt %, 50 wt %). The injection mold for fabricating the prototype plastic worm wheel was designed and made to reflect the CAE analysis results. Finally, the durability of prototype plastic worm wheel fabricated by the injection molding process was evaluated by the experimental method and the characteristics according to the glass fiber contents.

  1. Design optimization of the distributed modal filtering rod fiber for increasing single mode bandwidth

    Jørgensen, Mette Marie; Petersen, Sidsel Rübner; Laurila, Marko

    2012-01-01

    . Large preform tolerances are compensated during the fiber draw resulting in ultra low NA fibers with very large cores. In this paper, design optimization of the SM bandwidth of the DMF rod fiber is presented. Analysis of band gap properties results in a fourfold increase of the SM bandwidth compared...... LMA fiber amplifiers having high pump absorption through a pump cladding that is decoupled from the outer fiber. However, achieving ultra low NA for single-mode (SM) guidance is challenging, and thus different design strategies must be applied to filter out higher order modes (HOMs). The novel...... distributed modal filtering (DMF) design presented here enables SM guidance, and previous results have shown a SM mode field diameter of 60 μm operating in a 20 nm SM bandwidth. The DMF rod fiber has high index ring-shaped inclusions acting as resonators enabling SM guidance through modal filtering of HOMs...

  2. Extrinsic fiber-optic Fabry-Perot interferometer sensor for refractive index measurement of optical glass

    Chen Jihuan; Zhao Jiarong; Huang Xuguang; Huang Zhenjian

    2010-01-01

    A simple fiber-optic sensor based on Fabry-Perot interference for refractive index measurement of optical glass is investigated both theoretically and experimentally. A broadband light source is coupled into an extrinsic fiber Fabry-Perot cavity formed by the surfaces of a sensing fiber end and the measured sample. The interference signals from the cavity are reflected back into the same fiber. The refractive index of the sample can be obtained by measuring the contrast of the interference fringes. The experimental data meet with the theoretical values very well. The proposed technique is a new method for glass refractive index measurement with a simple, solid, and compact structure.

  3. Ultrasonic assisted consolidation of commingled thermoplastic/glass fibers rovings

    Francesca eLionetto

    2015-04-01

    Full Text Available Thermoplastic matrix composites are finding new applications in different industrial area thanks to their intrinsic advantages related to environmental compatibility and processability. The approach presented in this work consists in the development of a technology for the simultaneous deposition and consolidation of commingled thermoplastic rovings through to the application of high energy ultrasound. An experimental equipment, integrating both fiber impregnation and ply consolidation in a single process, has been designed and tested. It is made of an ultrasonic welder, whose titanium sonotrode is integrated on a filament winding machine. During winding, the commingled roving is at the same time in contact with the mandrel and the horn. The intermolecular friction generated by ultrasound is able to melt the thermoplastic matrix and impregnate the reinforcement fibers. The heat transfer phenomena occurring during the in situ consolidation were simulated solving by finite element (FE analysis an energy balance accounting for the heat generated by ultrasonic waves and the melting characteristics of the matrix. To this aim, a calorimetric characterization of the thermoplastic matrix has been carried out to obtain the input parameters for the model. The FE analysis has enabled to predict the temperature distribution in the composite during heating and cooling The simulation results have been validated by the measurement of the temperature evolution during ultrasonic consolidation.The reliability of the developed consolidation equipment was proved by producing hoop wound cylinder prototypes using commingled continuous E-glass rovings and Polypropylene (PP filaments. The consolidated composite cylinders are characterized by high mechanical properties, with values comparable with the theoretical ones predicted by the micromechanical analysis.

  4. Fabrication and physical properties of glass-fiber-reinforced thermoplastics for non-metal-clasp dentures.

    Nagakura, Manamu; Tanimoto, Yasuhiro; Nishiyama, Norihiro

    2017-11-01

    Recently, non-metal-clasp dentures (NMCDs) made from thermoplastic resins such as polyamide, polyester, polycarbonate, and polypropylene have been used as removable partial dentures (RPDs). However, the use of such RPDs can seriously affect various tissues because of their low rigidity. In this study, we fabricated high-rigidity glass-fiber-reinforced thermoplastics (GFRTPs) for use in RPDs, and examined their physical properties such as apparent density, dynamic hardness, and flexural properties. GFRTPs made from E-glass fibers and polypropylene were fabricated using an injection-molding. The effects of the fiber content on the GFRTP properties were examined using glass-fiber contents of 0, 5, 10, 20, 30, 40, and 50 mass%. Commercially available denture base materials and NMCD materials were used as controls. The experimental densities of GFRTPs with various fiber contents agreed with the theoretical densities. Dynamic micro-indentation tests confirmed that the fiber content does not affect the GFRTP surface properties such as dynamic hardness and elastic modulus, because most of the reinforcing glass fibers are embedded in the polypropylene. The flexural strength increased from 55.8 to 217.6 MPa with increasing glass-fiber content from 0 to 50 mass%. The flexural modulus increased from 1.75 to 7.42 GPa with increasing glass-fiber content from 0 to 50 mass%, that is, the flexural strength and modulus of GFRTP with a fiber content of 50 mass% were 3.9 and 4.2 times, respectively, those of unreinforced polypropylene. These results suggest that fiber reinforcement has beneficial effects, and GFRTPs can be used in NMCDs because their physical properties are better than those of controls. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2254-2260, 2017. © 2016 Wiley Periodicals, Inc.

  5. Dynamic mechanical and dielectric behavior of banana–glass hybrid fiber reinforced polyester composites.

    Pothan, LA

    2009-01-01

    Full Text Available Hybrid composites of glass and banana fiber (obtained from the pseudo stem of Musa sapientum) in polyester matrix, are subjected to dynamic mechanical analysis over a range of temperature and three different frequencies. The effect of temperature...

  6. Recycled Glass Fiber Reinforced Polymer Composites Incorporated in Mortar for Improved Mechanical Performance

    2017-12-11

    Glass fiber reinforced polymer (GFRP) recycled from retired wind turbines was implemented in mortar as a volumetric replacement of sand during the two phases of this study. In Phase I, the mechanically refined GFRP particle sizes were sieved for four...

  7. Health monitoring of precast bridge deck panels reinforced with glass fiber reinforced polymer (GFRP) bars.

    2012-03-01

    The present research project investigates monitoring concrete precast panels for bridge decks that are reinforced with Glass Fiber Reinforced Polymer (GFRP) bars. Due to the lack of long term research on concrete members reinforced with GFRP bars, lo...

  8. Study on vibration alleviating properties of glass fiber reinforced polymer concrete through orthogonal tests

    Bai Wenfeng; Zhang Jianhua; Yan Peng; Wang Xinli

    2009-01-01

    Polymer concrete (PC), because of its good vibration alleviating properties, is a proper material for elementary machine parts in high-precision machine tools. Glass fiber was applied in PC to improve its mechanical properties, and the material obtained is called glass fiber reinforced polymer concrete (GFRPC). The best parameter to estimate the vibration alleviating property is damping ratio. Orthogonal tests were carried out to prepare GFRPC specimens with different component proportions. Damping ratio of the GFRPC specimens was measured. The effect of the factors considered in the experiments on damping ratio of GFRPC was studied. Results of the tests show that granite proportion plays the most important role in determining damping ratio of GFRPC, then flexibilizer dosage and glass fiber length, while epoxy resin dosage and glass fiber dosage play a comparatively less important part. Detailed descriptions were made about how the considered factors affect damping ratio of GFRPC in this paper

  9. Isothermal and hygrothermal agings of hybrid glass fiber/carbon fiber composite

    Barjasteh, Ehsan

    New applications of fiber-reinforced polymer composites (FRPCs) are arising in non-traditional sectors of industry, such as civil infrastructure, automotive, and power distribution. For example, composites are being used in place of steel to support high-voltage overhead conductors. In this application, conductive strands of aluminum are wrapped around a solid composite rod comprised of unidirectional carbon and glass fibers in an epoxy matrix, which is commercially called ACCC conductor. Composite-core conductors such as these are expected to eventually replace conventional steel-reinforced conductors because of the reduced sag at high temperatures, lower weight, higher ampacity, and reduced line losses. Despite the considerable advantages in mechanical performance, long-term durability of composite conductors is a major concern, as overhead conductors are expected to retain properties (with minimal maintenance) over a service life that spans multiple decades. These concerns stem from the uncertain effects of long-term environmental exposure, which includes temperature, moisture, radiation, and aggressive chemicals, all of which can be exacerbated by cyclic loads. In general, the mechanical and physical properties of polymer composites are adversely affected by such environmental factors. Consequently, the ability to forecast changes in material properties as a function of environmental exposure, particularly bulk mechanical properties, which are affected by the integrity of fiber-matrix interfaces, is required to design for extended service lives. Polymer composites are susceptible to oxidative degradation at high temperatures approaching but not quite reaching the glass transition temperature ( Tg). Although the fibers are stable at such temperatures, the matrix and especially the fiber-matrix interface can undergo degradation that affects the physical and mechanical properties of the structure over time. Therefore, as a first step, the thermal aging of an

  10. High-Strength / High Alkaline Resistant Fe-Phosphate Glass Fibers as Concrete Reinforcement

    Mariano Velez

    2008-03-31

    Calcium-iron-phosphate glasses were developed whose chemical durabilities in alkaline solutions (pH 13) were comparable or superior to those of commercial alkaline-resistant (AR) silica-based glasses. However, the tensile strength of Ca-Fe-phosphate fibers, after being exposed to alkaline environments, including wet Portland cement pastes, is lower than that of current AR silicate fibers. Another series of Ca-Fe-phosphate glasses were developed with excellent chemical durability in strong acidic solutions (H2SO4, HF), indicating potential applications where silica-based fibers degrade very quickly, including E-glass. The new Ca-Fe-phosphate glasses can be melted and processed 300 to 500°C lower than silica-based glasses. This offers the possibility of manufacturing glass fibers with lower energy costs by 40-60% and the potential to reduce manufacturing waste and lower gas emissions. It was found that Ca-Fe-phosphate melts can be continuously pulled into fibers depending on the slope of the viscosity-temperature curve and with viscosity ~100 poise, using multi-hole Pt/Rh bushings.

  11. Gas refractometry based on an all-fiber spatial optical filter.

    Silva, Susana; Coelho, L; André, R M; Frazão, O

    2012-08-15

    A spatial optical filter based on splice misalignment between optical fibers with different diameters is proposed for gas refractometry. The sensing head is formed by a 2 mm long optical fiber with 50 μm diameter that is spliced with a strong misalignment between two single-mode fibers (SMF28) and interrogated in transmission. The misalignment causes a Fabry-Perot behavior along the reduced-size fiber and depending on the lead-out SMF28 position, it is possible to obtain different spectral responses, namely, bandpass or band-rejection filters. It is shown that the spatial filter device is highly sensitive to refractive index changes on a nitrogen environment by means of the gas pressure variation. A maximum sensitivity of -1390 nm/RIU for the bandpass filter was achieved. Both devices have shown similar temperature responses with an average sensitivity of 25.7 pm/°C.

  12. Effect of fiber content on flexural properties of glass fiber-reinforced polyamide-6 prepared by injection molding.

    Nagakura, Manamu; Tanimoto, Yasuhiro; Nishiyama, Norihiro

    2017-07-26

    The use of non-metal clasp denture (NMCD) materials may seriously affect the remaining tissues because of the low rigidity of NMCD materials such as polyamides. The purpose of this study was to develop a high-rigidity glass fiber-reinforced thermoplastic (GFRTP) composed of E-glass fiber and polyamide-6 for NMCDs using an injection molding. The reinforcing effects of fiber on the flexural properties of GFRTPs were investigated using glass fiber content ranging from 0 to 50 mass%. Three-point bending tests indicated that the flexural strength and elastic modulus of a GFRTP with a fiber content of 50 mass% were 5.4 and 4.7 times higher than those of unreinforced polyamide-6, respectively. The result showed that the physical characteristics of GFRTPs were greatly improved by increasing the fiber content, and the beneficial effects of fiber reinforcement were evident. The findings suggest that the injection-molded GFRTPs are adaptable to NMCDs because of their excellent mechanical properties.

  13. Effect of discrete glass fibers on the behavior of R.C. Beams exposed to fire

    Magdy Riad

    2017-08-01

    Full Text Available The main objective of this paper is to investigate the effect of adding discrete glass fibers on the behavior of reinforced concrete (RC beams under different fire and cooling conditions. Eighteen beams with different concrete compressive strengths were tested to study the behavior of reinforced concrete (RC beams containing discrete glass fibers when exposed to different fire and cooling conditions. Nine beams were prepared from normal strength concrete (NSC with compressive strength equal to 35 MPa while the other beams were prepared from high strength concrete (HSC with compressive strength equal to 60 MPa. The beams contained different contents of discrete glass fibers. The modes of failure of tested specimens show that the crack patterns change according to fire condition and fiber content. Analysis of test results show that adding discrete glass fibers to NSC increased the residual stiffness of the tested specimens after firing and decreased the rate of the deflection gain during firing. Also adding fibers to concrete has a limited positive effect on the ultimate strength of the specimens compared to the control specimens. Its effect on deflection due to fire is more pronounced. Finally, the recommended optimum ratio of discrete glass fibers is not more than 0.5% of the total concrete weight.

  14. Preparation and investigation of Ge-S-I glasses for infrared fiber optics

    Velmuzhov, A. P.; Sukhanov, M. V.; Plekhovich, A. D.; Snopatin, G. E.; Churbanov, M. F.; Iskhakova, L. D.; Ermakov, R. P.; Kotereva, T. V.; Shiryaev, V. S.

    2016-02-01

    Glass samples of [GeSx]90I10 (x = 1.5, 1.7, 2.0, 2.3, 2.45, 2.6) compositions were prepared, and some their thermal, optical properties as well as tendency to crystallization were investigated. The compositional dependences of glass transition temperature, volume fraction of crystallized phase and activation energy of glass formation (Eg) have nonmonotonic character with a maximum for [GeS2.0]90I10 glass. Glasses of 85.8GeS2-14.2GeI4 and [GeS1.5]90I10 compositions are identified as promising for preparation of optical fiber. For the first time, Ge-S-I glass fibers were produced. Minimum optical losses in 85.8GeS2-14.2GeI4 glass fiber were 2.7 dB/m at a wavelength of 5.1 μm, and that in [GeS1.5]90I10 glass fiber were 14.5 dB/m at 5.5 μm.

  15. Real-time single airborne nanoparticle detection with nanomechanical resonant filter-fiber

    Schmid, Silvan; Kurek, Maksymilian; Adolphsen, Jens Q

    2013-01-01

    Nanomechanical resonators have an unprecedented mass sensitivity sufficient to detect single molecules, viruses or nanoparticles. The challenge with nanomechanical mass sensors is the direction of nano-sized samples onto the resonator. In this work we present an efficient inertial sampling...... study of single filter-fiber behavior. We present the direct measurement of diffusive nanoparticle collection on a single filter-fiber qualitatively confirming Langmuir's model from 1942....

  16. Tunable bandpass filter based on photonic crystal fiber filled with multiple liquid crystals

    Scolari, Lara; Tartarini, G.; Borelli, E.

    2007-01-01

    A tunable bandpass filter based on a photonic crystal fiber filled with two different liquid crystals is demonstrated. 130 nm bandwidth tunability is achieved by tuning the temperature from 30degC to 90degC.......A tunable bandpass filter based on a photonic crystal fiber filled with two different liquid crystals is demonstrated. 130 nm bandwidth tunability is achieved by tuning the temperature from 30degC to 90degC....

  17. A Polarization Maintaining Filter based on a Liquid-Crystal-Photonic-Bandgap-Fiber

    Scolari, Lara; Olausson, Christina Bjarnal Thulin; Turchinovich, Dmitry

    2008-01-01

    A polarization maintaining filter based on a liquid-crystal-photonic-bandgap-fiber is demonstrated. Its polarization extinction ratio is 14 dB at 1550 nm. Its tunability is 150 nm.......A polarization maintaining filter based on a liquid-crystal-photonic-bandgap-fiber is demonstrated. Its polarization extinction ratio is 14 dB at 1550 nm. Its tunability is 150 nm....

  18. Interlaminar/interfiber failure of unidirectional glass fiber reinforced composites used for wind turbine blades

    Leong, Martin Klitgaard; Overgaard, Lars C. T.; M. Daniel,, Isaac

    2013-01-01

    A unidirectional glass fiber/epoxy composite was characterized under multi-axial loading by testing off-axis specimens under uniaxial tension and compression at various angles relative to the fiber direction. Iosipescu shear tests were performed with both symmetric and asymmetric specimens. Tests...

  19. Tm-Yb Doped Optical Fiber Performance with Variation of Host-Glass Composition

    Anirban Dhar

    2014-01-01

    Full Text Available The fabrication process of Thulium-Ytterbium doped optical fiber comprising different host glass through the Modified Chemical Vapor Deposition (MCVD coupled with solution doping technique is presented. The material and optical performance of different fibers are compared with special emphasis on their lasing efficiency for 2 µm application.

  20. Mechanical Characterization and Fractography of Glass Fiber/Polyamide (PA6) Composites

    Raghavalu Thirumalai, Durai Prabhakaran; Pillai, Saju; Charca, Samuel

    2015-01-01

    The mechanical properties of the glass fiber reinforced Polyamide (PA6) composites made by prepreg tapes and commingled yarns were studied by in-plane compression, short-beam shear, and flexural tests. The composites were fabricated with different fiber volume contents (prepregs—47%, 55%, 60%, an...

  1. Hybrid carbon/glass fiber composites: Micromechanical analysis of structure–damage resistance relationships

    Mishnaevsky, Leon; Dai, Gaoming

    2014-01-01

    A computational study of the effect of microstructure of hybrid carbon/glass fiber composites on their strength is presented. Unit cells with hundreds of randomly located and misaligned fibers of various properties and arrangements are subject to tensile and compression loading, and the evolution...... strength than pure composites, while the strength of hybrid composites under inform force loading increases steadily with increasing the volume content of carbon fibers....... of fiber damages is analyzed in numerical experiments. The effects of fiber clustering, matrix properties, nanoreinforcement, load sharing rules on the strength and damage resistance of composites are studied. It was observed that hybrid composites under uniform displacement loading might have lower...

  2. Glass and Process Development for the Next Generation of Optical Fibers: A Review

    John Ballato

    2017-03-01

    Full Text Available Applications involving optical fibers have grown considerably in recent years with intense levels of research having been focused on the development of not only new generations of optical fiber materials and designs, but also on new processes for their preparation. In this paper, we review the latest developments in advanced materials for optical fibers ranging from silica, to semi-conductors, to particle-containing glasses, to chalcogenides and also in process-related innovations.

  3. Distributed mode filtering rod fiber amplifier delivering 292W with improved mode stability

    Laurila, Marko; Jørgensen, Mette Marie; Hansen, Kristian Rymann

    2012-01-01

    We demonstrate a high power fiber (85μm core) amplifier delivering up to 292Watts of average output power using a mode-locked 30ps source at 1032nm. Utilizing a single mode distributed mode filter bandgap rod fiber, we demonstrate 44% power improvement before the threshold-like onset of mode inst...

  4. Mode-routed fiber-optic add-drop filter

    Moslehi, Behzad (Inventor); Black, Richard James (Inventor); Shaw, Herbert John (Inventor)

    2000-01-01

    New elements mode-converting two-mode grating and mode-filtering two-mode coupler are disclosed and used as elements in a system for communications, add-drop filtering, and strain sensing. Methods of fabrication for these new two-mode gratings and mode-filtering two-mode couplers are also disclosed.

  5. On turbulence structure in vertical pipe flow of fiber suspensions [refractivity, flow measurement, turbulent flow, glass fibers, fluid flow

    Steen, M.

    1989-01-01

    A suspension of glass fibers in alcohol has been used to investigate a upward vertical developing pipe flow. The refractive index of the alcohol was matched to that of the glass fibers, making the whole suspension transparent. Laser Doppler Anemometry (LDA) was applied, and fluid velocities could then be measured for consistencies up to c = 12 g/l. Radial profiles of axial U-velocity and turbulence spectra have been recorded at various positions (z/D = 2, 5, 36) downstream of an orifice (step) with 64% open area. Measurements were taken for different consistencies (c = 1.2, 12 g/l), fiber lengths (l = 1, 3 mm) and Reynolds numbers (R e = 8.5 ⋅ 10 3 , 6.5 ⋅ 10 4 ). The fiber crowding factor (n f ) has been used to discuss the observed effects of the present fibers on momentum transfer and turbulence structure. The results show both an increase (l= 1 mm, c= 1.2 g/l) and decrease (l=3 mm, c = 12 g/l) in turbulence levels in the presence of fibers. Suspensions with long fibers at the highest consistency show plug flow in parts of the core. This causes damping of the turbulence mainly at smaller length scales. For short fibers at low consistency, the increased turbulent energy was mainly observed at small length scales in the spectrum. (author)

  6. Polymeric THz 2D Photonic Crystal Filters Fabricated by Fiber Drawing

    Stecher, Matthias; Jansen, Christian; Ahmadi-Boroujeni, Mehdi

    2012-01-01

    In this paper, we report on a new form of polymeric 2D photonic crystal filters for THz frequencies fabricated using a standard fiber drawing technique. The band stop filters were modeled and designed using the generalized multipole technique. The frequency and angle-dependent transmission...

  7. Abrasion Resistance and Mechanical Properties of Waste-Glass-Fiber-Reinforced Roller-compacted Concrete

    Yildizel, S. A.; Timur, O.; Ozturk, A. U.

    2018-05-01

    The potential use of waste glass fibers in roller-compacted concrete (RCC) was investigated with the aim to improve its performance and reduce environmental effects. The research was focused on the abrasion resistance and compressive and flexural strengths of the reinforced concrete relative to those of reference mixes without fibers. The freeze-thaw resistance of RCC mixes was also examined. It was found that the use of waste glass fibers at a rate of 2 % increased the abrasion resistance of the RCC mixes considerably.

  8. Influences of chemical aging on the surface morphology and crystallization behavior of basaltic glass fibers

    Lund, Majbritt Deichgræber; Yue, Yuanzheng

    2008-01-01

    The impact of aging in high humidity and water on the surface morphology and crystallization behavior of basaltic glass fibers has been studied using scanning electron microscopy, transmission electron microscopy, calorimetry and X-ray diffraction. The results show that interaction between...... the fibers and the surrounding media (high humidity or water at 70 C) leads to chemical changes strongly affecting the surface morphology. The crystallization peak temperature of the basaltic glass fibers are increased without changing the onset temperature, this may be caused by a chemical depletion...

  9. Investigation of mechanical properties of hemp/glass fiber reinforced nano clay hybrid composites

    Unki, Hanamantappa Ningappa; Shivanand, H. K.; Vidyasagar, H. N.

    2018-04-01

    Over the last twenty to thirty years composite materials have been used in engineering field. Composite materials possess high strength, high strength to weight ratio due to these facts composite materials are becoming popular among researchers and scientists. The major proportion of engineering materials consists of composite materials. Composite materials are used in vast applications ranging from day-to-day household articles to highly sophisticated applications. In this paper an attempt is made to prepare three different composite materials using e-glass and Hemp. In this present investigation hybrid composite of Hemp, Glass fiber and Nano clay will be prepared by Hand-layup technique. The glass fiber used in this present investigation is E-glass fiber bi-directional: 90˚ orientation. The composite samples will be made in the form of a Laminates. The wt% of nanoclay added in the preparation of sample is 20 gm constant. The fabricated composite Laminate will be cut into corresponding profiles as per ASTM standards for Mechanical Testing. The effect of addition of Nano clay and variation of Hemp/glass fibers will be studied. In the present work, a new Hybrid composite is developed in which Hemp, E glass fibers is reinforced with epoxy resin and with Nano clay.

  10. Evanescent field infrared spectroscopy using chalcogenide glass fiber

    Katz Moti

    1992-06-01

    In the last few years a simple and cheap fiber-optics based spectroscopy method was developed for the investigation of liquids, pastes gases and thin layers. The fiber is immersed in the sample, and the investigated material becomes the fiber cladding. the interaction between the guided radiation in the fiber and the specimen is taking place by evanescent field which extends outside the fiber. This work concentrates in the quantitative characterization of the absorption of the evanescent field by the fiber cladding (the specimen). This subject was dealt with only briefly in the earlier works, and the aim of this work is to obtain a comprehensive understanding of this issue. (author)

  11. Investigation of mechanical properties of kenaf, hemp and E-glass fiber reinforced composites

    Dinesh, Veena; Shivanand, H. K.; Vidyasagar, H. N.; Chari, V. Srinivasa

    2018-04-01

    Recently the use of fiber reinforced polymer composite in the automobile, aerospace overwhelming designing sectors has increased tremendously due to the ecological issues and health hazard possessed by the synthetic fiber during disposal and manufacturing. The paper presents tensile strength, flexural strength and hardness of kenaf-E glass-kenaf, hemp-E glass-hemp and kenaf-E glass-hemp fiber reinforced polyester composites. The composite plates are shaped according to the standard geometry and uni-axially loaded in order to investigate the tensile responses of each combination. In addition to the physical and mechanical properties, processing methods and application of kenaf and hemp fiber composites is also discussed.

  12. Intrinsic strength of sodium borosilicate glass fibers by using a two-point bending technique

    Nishikubo, Y; Yoshida, S; Sugawara, T; Matsuoka, J

    2011-01-01

    Flaws existing on glass surface can be divided into two types, extrinsic and intrinsic. Although the extrinsic flaws are generated during processing and using, the intrinsic flaws are regarded as structural defects which result from thermal fluctuation. It is known that the extrinsic flaws determine glass strength, but effects of the intrinsic flaws on the glass strength are still unclear. Since it is considered that the averaged bond-strength and the intrinsic flaw would affect the intrinsic strength, the intrinsic strength of glass surely depends on the glass composition. In this study, the intrinsic failure strain of the glass fibers with the compositions of 20Na 2 O-40xB 2 O 3 -(80-40x)SiO 2 (mol%, x = 0, 0.5, 1.0, 1.5) were measured by using a two-point bending technique. The failure strength was estimated from the failure strain and Young's modulus of glass. It is elucidated that two-point bending strength of glass fiber decreases with increasing B 2 O 3 content in glass. The effects of the glass composition on the intrinsic strength are discussed in terms of elastic and inelastic deformation behaviors prior to fracture.

  13. Mechanical and abrasive wear characterization of bidirectional and chopped E-glass fiber reinforced composite materials

    Siddhartha,; Gupta, Kuldeep

    2012-01-01

    Highlights: ► Bi-directional and chopped E-glass fiber reinforced epoxy composites are fabricated. ► Three body abrasive wear behavior of fabricated composites has been assessed. ► Results are validated against existing microscopic models of Lancaster and Wang. ► Tensile strength of bi-directional E-glass fiber reinforced composites increases. ► Chopped glass fiber composites are found better in abrasive wear situations. -- Abstract: Bi-directional and chopped E-glass fiber reinforced epoxy composites are fabricated in five different (15, 20, 25, 30 and 35) wt% in an epoxy resin matrix. The mechanical characterization of these composites is performed. The three body abrasive wear behavior of fabricated composites has been assessed under different operating conditions. Abrasive wear characteristics of these composites are successfully analysed using Taguchi’s experimental design scheme and analysis of variance (ANOVA). The results obtained from these experiments are also validated against existing microscopic models of Ratner-Lancaster and Wang. It is observed that quite good linear relationships is held between specific wear rate and reciprocal of ultimate strength and strain at tensile fracture of these composites which is an indicative that the experimental results are in fair agreement with these existing models. Out of all composites fabricated it is found that tensile strength of bi-directional E-glass fiber reinforced composites increases because of interface strength enhancement. Chopped glass fiber reinforced composites are observed to perform better than bi-directional glass fiber reinforced composites under abrasive wear situations. The morphology of worn composite specimens has been examined by scanning electron microscopy (SEM) to understand about dominant wear mechanisms.

  14. Study of lanthanum aluminum silicate glasses for passive and active optical fibers

    Schuster, K.; Litzkendorf, D.; Grimm, S.; Kobelke, J.; Schwuchow, A.; Ludwig, A.; Leich, M.; Jetschke, S.; Dellith, J.; Auguste, J.-L.; Leparmentier, S.; Humbert, G.; Werner, G.

    2013-03-01

    We report on SiO2-Al2O3-La2O3 glasses - with and without Yb2O3 - suitable for nonlinear and fiber laser applications. We also present successful supercontinuum generation and fiber laser operation around 1060 nm in step-index fibers. We have optimized the glass compositions in terms of thermal and optical requirements for both a high La2O3 (24 mol%) and Yb2O3(6 mol%) concentration. The aluminum concentration was adjusted to about 21 mol% Al2O3 to increase the solubility of lanthanum and ytterbium in the glass beyond possible MCVD based techniques. The glasses have been characterized by dilatometrical methods to find transition temperatures from 860 to 880°C and thermal expansion coefficients between 4.1 and 7.0 × 10-6 K-1. Structured step index fibers with a SiO2-Al2O3-La2O3 core and silica cladding have been realized showing a fiber loss minimum of about 500 dB/km at 1200 nm wavelength. The chromatic dispersion could be adjusted to shift the zero dispersion wavelength (ZDW) close to the pump wavelength of 1550 nm in a supercontinuum generation setup. First fiber laser experiments show an efficiency of about 41 % with a remarkably reduced photodarkening compared to MCVD based fibers.

  15. The effect of pressure changes during simulated diving on the pull out strength of glass fiber posts

    Meenal Nitin Gulve

    2013-01-01

    Conclusion: Dentist should consider using resin reinforced glass ionomer or resin cement, for the cementation of glass fiber post, for the patients such as divers, who are likely to be exposed to pressure cycling.

  16. Fabry-Perot interferometer fiber tip sensor based on a glass microsphere glued at the etched end of multimode fiber

    Chen, Weiping P.; Wang, Dongning N.; Xu, Ben; Wang, Zhaokun K.; Zhao, Chun-Liu

    2017-05-01

    We demonstrate an optical Fabry-Perot interferometer fiber tip sensor based on a glass microsphere glued at the etched end of a multimode fiber. The fiber device is miniature and robust, with a convenient reflection mode of operation, a high temperature sensitivity of 202.6 pm/°C within the range from 5°C to 90°C, a good refractive index sensitivity of ˜119 nm/RIU within the range from 1.331 to 1.38, and a gas pressure sensitivity of 0.19 dB/MPa.

  17. A study of glasses-type color CGH using a color filter considering reduction of blurring

    Iwami, Saki; Sakamoto, Yuji

    2009-02-01

    We have developed a glasses-type color computer generated hologram (CGH) by using a color filter. The proposed glasses consist of two "lenses" made of overlapping holograms and color filters. The holograms, which are calculated to reconstruct images in each primary color, are divided to small areas, which we called cells, and superimposed on one hologram. In the same way, colors of the filter correspond to the hologram cells. We can configure it very simply without a complex optical system, and the configuration yields a small and light weight system suitable for glasses. When the cell is small enough, the colors are mixed and reconstructed color images are observed. In addition, color expression of reconstruction images improves, too. However, using small cells blurrs reconstructed images because of the following reasons: (1) interference between cells because of the correlation with the cells, and (2) reduction of resolution caused by the size of the cell hologram. We are investigating in order to make a hologram that has high resolution reconstructed color images without ghost images. In this paper, we discuss (1) the details of the proposed glasses-type color CGH, (2) appropriate cell size for an eye system, (3) effects of cell shape on the reconstructed images, and (4) a new method to reduce the blurring of the images.

  18. Influence of the Processing Parameters on the Fiber-Matrix-Interphase in Short Glass Fiber-Reinforced Thermoplastics

    Anna Katharina Sambale

    2017-06-01

    Full Text Available The interphase in short fiber thermoplastic composites is defined as a three-dimensional, several hundred nanometers-wide boundary region at the interface of fibers and the polymer matrix, exhibiting altered mechanical properties. This region is of key importance in the context of fiber-matrix adhesion and the associated mechanical strength of the composite material. An interphase formation is caused by morphological, as well as thermomechanical processes during cooling of the plastic melt close to the glass fibers. In this study, significant injection molding processing parameters are varied in order to investigate the influence on the formation of an interphase and the resulting mechanical properties of the composite. The geometry of the interphase is determined using nano-tribological techniques. In addition, the influence of the glass fiber sizing on the geometry of the interphase is examined. Tensile tests are used in order to determine the resulting mechanical properties of the produced short fiber composites. It is shown that the interphase width depends on the processing conditions and can be linked to the mechanical properties of the short fiber composite.

  19. Optimal Performance Simulation of a Metal Fiber Filter for Capturing Radioactive Aerosols

    Lee, Seung Uk; Lee, Chan Hyun; Park, Min Chan; Lee, Jaek Eun

    2016-01-01

    In this study, the metal fiber filter used for removing radioactive aerosol is systematically dissected and studied in order to figure out the optimal design which can be applied to the actual operation conditions in nuclear heating, ventilation and air conditioning (HVAC) systems for particle collection. In order to derive the optimal design for metal fiber HEPA filter, a numerical model is developed and its results are compared to experimental data to test reliability. Moreover, sensitivity analysis is performed using important parameters to determine which parameters have large influence on the filter performance. Using the model developed in this study, optimal design parameters for pleated metal fiber filters are derived which include fiber diameter less than 4 μm, solidity larger than 0.2, filter thickness larger than 1 mm, and face velocity lower than 5 cm/s. With these conditions, the metal filter qualified for the HEPA filter standard which specified 99.97% efficiency in the 0.3 μm particle size range.

  20. Effects of glass fiber mesh with different fiber content and structures on the compressive properties of complete dentures.

    Yu, Sang-Hui; Cho, Hye-Won; Oh, Seunghan; Bae, Ji-Myung

    2015-06-01

    No study has yet evaluated the strength of complete dentures reinforced with glass fiber meshes with different content and structures. The purpose of this study was to compare the reinforcing effects of glass fiber mesh with different content and structures with that of metal mesh in complete dentures. Two types of glass fiber mesh were used: SES mesh (SES) and glass cloth (GC2, GC3, and GC4). A metal mesh was used for comparison. The complete dentures were made by placing the reinforcement 1 mm away from the tissue surface. A control group was prepared without any reinforcement (n=10). The compressive properties were measured by a universal testing machine at a crosshead speed of 5 mm/min. The results were analyzed with the Kruskal-Wallis test and the Duncan multiple range test (α=.05). The fracture resistance of the SES group was significantly higher than that of the control, GC4, and metal groups (asymptotic P=.004), but not significantly different from the GC2 and GC3 groups. The toughness of the SES and GC3 groups was significantly higher than that of the others (asymptotic Pglass fiber mesh seemed more important than the structures. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  1. Proof-testing and probabilistic lifetime estimation of glass fibers for sensor applications.

    Komachiya, M; Minamitani, R; Fumino, T; Sakaguchi, T; Watanabe, S

    1999-05-01

    The mechanical reliability of sensing glass fiber is one of the important problems in the practical use of fiber-optic sensors. To ensure long-term reliability on a mass-production level, a method of proof-testing is applied to a sensing glass fiber that will be subjected to mechanical deformation in its service situation. We propose to employ a higher strain level (screening level) in the proof-testing with a fiber-recoating technique that can suppress excessive damage during the testing. We consider a standard lifetime of 15 years of automotive applications and ensure a practical level of failure probability by a model calculation by using the strength data of a prototype fiber with the method of fracture-mechanics theory.

  2. Glass-ceramic optical fiber containing Ba2TiSi2O8 nanocrystals for frequency conversion of lasers.

    Fang, Zaijin; Xiao, Xusheng; Wang, Xin; Ma, Zhijun; Lewis, Elfed; Farrell, Gerald; Wang, Pengfei; Ren, Jing; Guo, Haitao; Qiu, Jianrong

    2017-03-30

    A glass-ceramic optical fiber containing Ba 2 TiSi 2 O 8 nanocrystals fabricated using a novel combination of the melt-in-tube method and successive heat treatment is reported for the first time. For the melt-in-tube method, fibers act as a precursor at the drawing temperature for which the cladding glass is softened while the core glass is melted. It is demonstrated experimentally that following heat treatment, Ba 2 TiSi 2 O 8 nanocrystals with diameters below 10 nm are evenly distributed throughout the fiber core. Comparing to the conventional rod-in-tube method, the melt-in-tube method is superior in terms of controllability of crystallization to allow for the fabrication of low loss glass-ceramic fibers. When irradiated using a 1030 nm femtosecond laser, an enhanced green emission at a wavelength of 515 nm is observed in the glass-ceramic fiber, which demonstrates second harmonic generation of a laser action in the fabricated glass-ceramic fibers. Therefore, this new glass-ceramic fiber not only provides a highly promising development for frequency conversion of lasers in all optical fiber based networks, but the melt-in-tube fabrication method also offers excellent opportunities for fabricating a wide range of novel glass-ceramic optical fibers for multiple future applications including fiber telecommunications and lasers.

  3. Guiding hard x rays with glass polycapillary fiber

    Xiao, Q.F.; Ponomarev, I.Y.; Kolomitsev, A.I.; Gibson, D.M.; Dilmanian, F.A.; Nachaliel, E.

    1993-01-01

    X rays can be guided through a polycapillary fiber by multiple total reflections from the smooth channel walls of the fiber. Using monochromatic Synchrotron Radiation at energies of 22 and 44 keV, we measured the efficiency of transmission of x rays through polycapillary fibers with channel diameters of about 13 μm. Efficiencies of 57.3% and 54.5% for 22 keV and 44 keV x rays, respectively, were obtained with a 120-mm-long straight polycapillary fiber aligned with the incident beam. These values are close to the open fraction of the fiber, which is about 60%. In addition, transmission efficiency was measured as a function of the tilt angle between the incident beam and the axis of the fiber. We also measured the transmission efficiency as a function of the deflection angle for a 114-mm-long curved polycapillary fiber. The measurements are compared with a ray-tracing simulation

  4. Influence of Glass Fiber on Fresh and Hardened Properties of Self Compacting Concrete

    Bharathi Murugan, R.; Haridharan, M. K.; Natarajan, C.; Jayasankar, R.

    2017-07-01

    The practical need of self-compacting concrete (SCC) is increasing due to increase in the infrastructure competence all over the world. The effective way of increasing the strength of concrete and enhance the behaviour under extreme loading (fire) is the keen interest. Glass fibers were added for five different of volume fractions (0%, 0.1%, 0.3%, 0.5% and 0.6%) to determine the optimum percentage of glass fiber without compensating the fresh properties and enhanced hardened properties of SCC concrete. The fresh state of concrete is characterized by slump flow, T-50cm slump flow, and V-funnel and L- box tests. The results obtained in fresh state are compared with the acceptance criteria of EFNARC specification. Concrete specimens were casted to evaluate the hardened properties such as compressive strength, split tensile strength, flexural strength and modulus of elasticity. Incorporation the glass fiber into SCC reduces the workability but within the standard specification. The hardened properties of SCC glass fiber reinforced concrete were enhanced, due to bridging the pre-existing micro cracks in concrete by glass fiber addition.

  5. Developing particulate thin filter using coconut fiber for motor vehicle emission

    Wardoyo, A. Y. P.; Juswono, U. P.; Riyanto, S.

    2016-03-01

    Amounts of motor vehicles in Indonesia have been recognized a sharply increase from year to year with the increment reaching to 22 % per annum. Meanwhile motor vehicles produce particulate emissions in different sizes with high concentrations depending on type of vehicles, fuels, and engine capacity. Motor Particle emissions are not only to significantly contribute the atmosphric particles but also adverse to human health. In order to reduce the particle emission, it is needed a filter. This study was aimed to develop a thin filter using coconut fiber to reduce particulate emissions for motor vehicles. The filter was made of coconut fibers that were grinded into power and mixed with glues. The filter was tested by the measurements of particle concentrations coming out from the vehicle exhaust directly and the particle concentrations after passing through the filter. The efficiency of the filter was calculated by ratio of the particle concentrations before comming in the filter to the particle conentrations after passing through the filter. The results showed that the efficiency of the filter obtained more than 30 %. The efficiency increases sharply when a number of the filters are arranged paralelly.

  6. Glass wool filters for concentrating waterborne viruses and agricultural zoonotic pathogens

    Millen, Hana T.; Gonnering, Jordan C.; Berg, Ryan K.; Spencer, Susan K.; Jokela, William E.; Pearce, John M.; Borchardt, Jackson S.; Borchardt, Mark A.

    2012-01-01

    The key first step in evaluating pathogen levels in suspected contaminated water is concentration. Concentration methods tend to be specific for a particular pathogen group, for example US Environmental Protection Agency Method 1623 for Giardia and Cryptosporidium1, which means multiple methods are required if the sampling program is targeting more than one pathogen group. Another drawback of current methods is the equipment can be complicated and expensive, for example the VIRADEL method with the 1MDS cartridge filter for concentrating viruses2. In this article we describe how to construct glass wool filters for concentrating waterborne pathogens. After filter elution, the concentrate is amenable to a second concentration step, such as centrifugation, followed by pathogen detection and enumeration by cultural or molecular methods. The filters have several advantages. Construction is easy and the filters can be built to any size for meeting specific sampling requirements. The filter parts are inexpensive, making it possible to collect a large number of samples without severely impacting a project budget. Large sample volumes (100s to 1,000s L) can be concentrated depending on the rate of clogging from sample turbidity. The filters are highly portable and with minimal equipment, such as a pump and flow meter, they can be implemented in the field for sampling finished drinking water, surface water, groundwater, and agricultural runoff. Lastly, glass wool filtration is effective for concentrating a variety of pathogen types so only one method is necessary. Here we report on filter effectiveness in concentrating waterborne human enterovirus, Salmonella enterica, Cryptosporidium parvum, and avian influenza virus.

  7. Cross-correlated imaging of single-mode photonic crystal rod fiber with distributed mode filtering

    Laurila, Marko; Barankov, Roman; Jørgensen, Mette Marie

    2013-01-01

    Photonic crystal bandgap fibers employing distributed mode filtering design provide near diffraction-limited light outputs, a critical property of fiber-based high-power lasers. Microstructure of the fibers is tailored to achieve single-mode operation at specific wavelength by resonant mode...... identify regimes of resonant coupling between higher-order core modes and cladding band. We demonstrate a passive fiber design in which the higher-order modal content inside the single-mode guiding regime is suppressed by at least 20 dB even for significantly misaligned input-coupling configurations....

  8. Microstructured fibers with high lanthanum oxide glass core for nonlinear applications

    Kobelke, J.; Schuster, K.; Litzkendorf, D.; Schwuchow, A.; Kirchhof, J.; Bartelt, H.; Tombelaine, V.; Leproux, P.; Couderc, V.; Labruyere, A.

    2009-05-01

    We demonstrate a low loss microstructured fiber (MOF) with a high nonlinear glass core and silica holey cladding. The substitution of mostly used silica as core material of microstructured fibers by lanthanum oxide glass promises a high nonlinear conversion efficiency for supercontinuum (SC) generation. The glass composition is optimized in terms of thermochemical and optical requirements. The glass for the MOF core has a high lanthanum oxide concentration (10 mol% La2O3) and a good compatibility with the silica cladding. This is performed by adding a suitable alumina concentration up to 20 mol%. The lanthanum oxide glass preform rods were manufactured by melting technique. Besides purity issues the material homogeneity plays an important role to achieve low optical loss. The addition of fluorides allows the better homogenization of the glass composition in the preform volume by refining. The minimum attenuation of an unstructured fiber drawn from this glass is about 0.6 dB/m. It is mostly caused by decreasing of scattering effects. The microstructured silica cladding allows the considerable shifting of dispersive behavior of the MOF for an optimal pump light conversion. The MOF shows zero dispersion wavelengths (ZDW) of 1140 nm (LP01 mode) and 970 nm (LP11 mode). The supercontinuum generation was investigated with a 1064 nm pump laser (650 ps). It shows a broad band emission between 500 nm and 2200 nm.

  9. Strongly nonlinear optical glass fibers from noncentrosymmetric phase-change chalcogenide materials.

    Chung, In; Jang, Joon I; Malliakas, Christos D; Ketterson, John B; Kanatzidis, Mercouri G

    2010-01-13

    We report that the one-dimensional polar selenophosphate compounds APSe(6) (A = K, Rb), which show crystal-glass phase-change behavior, exhibit strong second harmonic generation (SHG) response in both crystal and glassy forms. The crystalline materials are type-I phase-matchable with SHG coefficients chi((2)) of 151.3 and 149.4 pm V(-1) for K(+) and Rb(+) salts, respectively, which is the highest among phase-matchable nonlinear optical (NLO) materials with band gaps over 1.0 eV. The glass of APSe(6) exhibits comparable SHG intensities to the top infrared NLO material AgGaSe(2) without any poling treatments. APSe(6) exhibit excellent mid-IR transparency. We demonstrate that starting from noncentrosymmetric phase-change materials such as APSe(6) (A = K, Rb), we can obtain optical glass fibers with strong, intrinsic, and temporally stable second-order nonlinear optical (NLO) response. The as-prepared glass fibers exhibit SHG and difference frequency generation (DFG) responses over a wide range of wavelengths. Raman spectroscopy and pair distribution function (PDF) analyses provide further understanding of the local structure in amorphous state of KPSe(6) bulk glass and glass fiber. We propose that this approach can be widely applied to prepare permanent NLO glass from materials that undergo a phase-change process.

  10. Preparation, mechanical, and in vitro properties of glass fiber-reinforced polycarbonate composites for orthodontic application.

    Tanimoto, Yasuhiro; Inami, Toshihiro; Yamaguchi, Masaru; Nishiyama, Norihiro; Kasai, Kazutaka

    2015-05-01

    Generally, orthodontic treatment uses metallic wires made from stainless steel, cobalt-chromium-nickel alloy, β-titanium alloy, and nickel-titanium (Ni-Ti) alloy. However, these wires are not esthetically pleasing and may induce allergic or toxic reactions. To correct these issues, in the present study we developed glass-fiber-reinforced plastic (GFRP) orthodontic wires made from polycarbonate and E-glass fiber by using pultrusion. After fabricating these GFRP round wires with a diameter of 0.45 mm (0.018 inch), we examined their mechanical and in vitro properties. To investigate how the glass-fiber diameter affected their physical properties, we prepared GFRP wires of varying diameters (7 and 13 µm). Both the GFRP with 13-µm fibers (GFRP-13) and GFRP with 7 µm fibers (GFRP-7) were more transparent than the metallic orthodontic wires. Flexural strengths of GFRP-13 and GFRP-7 were 690.3 ± 99.2 and 938.1 ± 95.0 MPa, respectively; flexural moduli of GFRP-13 and GFRP-7 were 25.4 ± 4.9 and 34.7 ± 7.7 GPa, respectively. These flexural properties of the GFRP wires were nearly equivalent to those of available Ni-Ti wires. GFRP-7 had better flexural properties than GFRP-13, indicating that the flexural properties of GFRP increase with decreasing fiber diameter. Using thermocycling, we found no significant change in the flexural properties of the GFRPs after 600 or 1,200 cycles. Using a cytotoxicity detection kit, we found that the glass fiber and polycarbonate components comprising the GFRP were not cytotoxic within the limitations of this study. We expect this metal-free GFRP wire composed of polycarbonate and glass fiber to be useful as an esthetically pleasing alternative to current metallic orthodontic wire. © 2014 Wiley Periodicals, Inc.

  11. Noise filtering in a multi-channel system using a tunable liquid crystal photonic bandgap fiber

    Petersen, Martin Nordal; Scolari, Lara; Tokle, Torger

    2008-01-01

    This paper reports on the first application of a liquid crystal infiltrated photonic bandgap fiber used as a tunable filter in an optical transmission system. The device allows low-cost amplified spontaneous emission (ASE) noise filtering and gain equalization with low insertion loss and broad...... tunability. System experiments show that the use of this filter increases for times the distance over which the optical signal-to-noise ratio (OSNR) is sufficient for error-free transmission with respect to the case in which no filtering is used....

  12. Two Octaves Supercontinuum Generation in Lead-Bismuth Glass Based Photonic Crystal Fiber

    Ryszard Buczynski

    2014-06-01

    Full Text Available In this paper we report a two octave spanning supercontinuum generation in a bandwidth of 700–3000 nm in a single-mode photonic crystal fiber made of lead-bismuth-gallate glass. To our knowledge this is the broadest supercontinuum reported in heavy metal oxide glass based fibers. The fiber was fabricated using an in-house synthesized glass with optimized nonlinear, rheological and transmission properties in the range of 500–4800 nm. The photonic cladding consists of 8 rings of air holes. The fiber has a zero dispersion wavelength (ZDW at 1460 nm. Its dispersion is determined mainly by the first ring of holes in the cladding with a relative hole size of 0.73. Relative hole size of the remaining seven rings is 0.54, which allows single mode performance of the fiber in the infrared range and reduces attenuation of the fundamental mode. The fiber is pumped into anomalous dispersion with 150 fs pulses at 1540 nm. Observed spectrum of 700–3000 nm was generated in 2 cm of fiber with pulse energy below 4 nJ. A flatness of 5 dB was observed in 950–2500 nm range.

  13. Highly Doped Phosphate Glass Fibers for Compact Lasers and Amplifiers: A Review

    Nadia Giovanna Boetti

    2017-12-01

    Full Text Available In recent years, the exploitation of compact laser sources and amplifiers in fiber form has found extensive applications in industrial and scientific fields. The fiber format offers compactness, high beam quality through single-mode regime and excellent heat dissipation, thus leading to high laser reliability and long-term stability. The realization of devices based on this technology requires an active medium with high optical gain over a short length to increase efficiency while mitigating nonlinear optical effects. Multicomponent phosphate glasses meet these requirements thanks to the high solubility of rare-earth ions in their glass matrix, alongside with high emission cross-sections, chemical stability and high optical damage threshold. In this paper, we review recent advances in the field thanks to the combination of highly-doped phosphate glasses and innovative fiber drawing techniques. We also present the main performance achievements and outlook both in continuous wave (CW and pulsed mode regimes.

  14. Analysis of the mechanical and thermal properties of jute and glass fiber as reinforcement epoxy hybrid composites.

    Braga, R A; Magalhaes, P A A

    2015-11-01

    This work describes the study to investigate and compare the mechanical and thermal properties of raw jute and glass fiber reinforced epoxy hybrid composites. To improve the mechanical properties, jute fiber was hybridized with glass fiber. Epoxy resin, jute and glass fibers were laminated in three weight ratios (69/31/0, 68/25/7 and 64/18/19) respectively to form composites. The tensile, flexural, impact, density, thermal and water absorption tests were carried out using hybrid composite samples. This study shows that the addition of jute fiber and glass fiber in epoxy, increases the density, the impact energy, the tensile strength and the flexural strength, but decreases the loss mass in function of temperature and the water absorption. Morphological analysis was carried out to observe fracture behavior and fiber pull-out of the samples using scanning electron microscope. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Push-out bond strength of fiber posts to root dentin using glass ionomer and resin modified glass ionomer cements

    Jefferson Ricardo PEREIRA

    2014-10-01

    Full Text Available OBJECTIVE: The purpose of this study was to assess the push-out bond strength of glass fiber posts to root dentin after cementation with glass ionomer (GICs and resinmodified glass ionomer cements (RMGICs. MATERIAL AND METHODS: Fifty human maxillary canines were transversally sectioned at 15 mm from the apex. Canals were prepared with a step back technique until the application of a #55 K-file and filled. Post spaces were prepared and specimens were divided into five groups according to the cement used for post cementation: Luting & Lining Cement; Fuji II LC Improved; RelyX Luting; Ketac Cem; and Ionoseal. After cementation of the glass fiber posts, all roots were stored at 100% humidity until testing. For push-out test, 1-mm thick slices were produced. The push-out test was performed in a universal testing machine at a crosshead speed of 0.5 mm/minute and the values (MPa were analyzed by Kolmogorov-Smirnov and Levene's tests and by two-way ANOVA and Tukey's post hoc test at a significance level of 5%. RESULTS: Fiber posts cemented using Luting & Lining Cement, Fuji II LC Improved, and Ketac Cem presented the highest bond strength to root dentin, followed by RelyX Luting. Ionoseal presented the lowest bond strength values (P>0.05. The post level did not influence the bond strength of fiber posts to root dentin (P=0.148. The major cause of failure was cohesive at the cement for all GICs and RMGICs. CONCLUSIONS: Except for Ionoseal, all cements provided satisfactory bond strength values.

  16. Design and engineering of IZO/Ag/glass solar filters for low-emissivity window performance

    Hernandez-Mainet, Luis C.; Aguilar, Miguel A.; Tamargo, Maria C.; Falcony, Ciro

    2017-10-01

    The electricity consumption in houses and commercial buildings generates about 18% of greenhouse gas emission. A critical issue of building energy consumption is heat and cooling loss through the window. Low-emissivity windows control thermal radiation through glass without decreasing the intensity of visible light. They are made up of optical filter coatings grown on a flat glass surface. Solar filters based on Ag/IZO multilayer films are grown and simulated on glass substrate. The targeted structure designs are grown by a sputtering system and characterized by scanning electron microscopy and x-ray diffraction techniques. To accurately simulate transmission spectrum, silver (Ag) and IZO optical constants were estimated by fitting ellipsometric data at different thicknesses. Transmission spectrum shows a good agreement among experiment and simulation. In addition, optical constant curves strongly show layer thickness dependence in both materials. In particular, the ultrathin Ag layer displays a percolation threshold in the vicinity of 15 nm, which leads to surface plasmon resonance with absorption at about 450 nm. These types of optical filter coatings would have potential applications as low-emission windows.

  17. Experimental Investigations on the effect of Additive on the Tensile Properties of Fiber Glass Fabric Lamina

    Nava Sai Divya, A.; Raghu Kumar, B., Dr; Lakshmi Narayana, G., Dr

    2017-09-01

    The main objective of this work is to investigate the effect of additives on tensile behaviour of fiber glass fabric at lamina level to explore an alternative skin material for the outer body of aerospace applications and machines. This experimental work investigates the effect of silica concentration in epoxy resin lapox L-12 on the tensile properties of glass fabric lamina of 4H-satin weave having 3.6 mm thickness. The lamina was prepared by using hand lay-up method and tests were conducted on it. Various tensile properties values obtained from experimentation were compared for four glass fiber lamina composites fabricated by adding the silica powder to resin bath. The effect of variations in silica concentration (0% SiO2, 5% SiO2, 10% SiO2 and 15% SiO2) on the tensile properties of prepared material revealed that maximum stiffness was obtained at 15% and yield strength at 10% SiO2 concentration in glass fiber lamina. Increasing the silica concentration beyond 10% had led to deterioration in the material properties. The experimentation that was carried out on test specimen was reasonably successful as the effect of silica powder as an additive in glass fiber lamina enhanced the mechanical properties up to certain limit. The underpinning microscopic behaviour at the source of these observations will be investigated in a follow up work.

  18. Laser printed glass planar lightwave circuits with integrated fiber alignment structures

    Desmet, A.; Radosavljevic, A.; Missinne, J.; Van Thourhout, D.; Van Steenberge, G.

    2018-02-01

    Femtosecond laser inscription allows straightforward manufacturing of glass planar lightwave circuits such as waveguides, interferometers, directional couplers, resonators and more complex structures. Fiber alignment structures are needed to facilitate communication with the glass planar lightwave circuit. In this study, a technique is described to create optical waveguides and alignment structures in the same laser exposure step. Using an industrial ytterbium-doped 1030 nm fiber laser pulses of 400 fs were focused into glass with a 0.4 NA objective causing permanent alteration of the material. Depending on laser parameters this modification allows direct writing of waveguides or the creation of channels after exposing the irradiated volumes to an etchant such as KOH. Writing of channels and waveguides with different laser powers, frequencies, polarisations, stage translation speeds and scan densities were investigated in fused silica and borosilicate glass. Waveguides with controlled dimensions were created, as well as etched U-grooves with a diameter of 126 μm and a sidewall roughness Ra of 255 nm. Cut back measurements were performed giving a waveguide propagation loss of 1.1 dB/cm in borosilicate glass. A coupling loss of 0.7 dB was measured for a transition between the waveguide and standard single mode fiber at 1550 nm, using index matching liquid. The described technique eliminates active alignment requirements and is useful for many applications such as microfluidic sensing, PLCs, fan-out connectors for multicore fibers and quantum optical networks.

  19. Structural considerations in design of lightweight glass-fiber composite pressure vessels

    Faddoul, J. R.

    1973-01-01

    The design concepts used for metal-lined glass-fiber composite pressure vessels are described, comparing the structural characteristics of the composite designs with each other and with homogeneous metal pressure vessels. Specific design techniques and available design data are identified. The discussion centers around two distinctly different design concepts, which provide the basis for defining metal lined composite vessels as either (1) thin-metal lined, or (2) glass fiber reinforced (GFR). Both concepts are described and associated development problems are identified and discussed. Relevant fabrication and testing experience from a series of NASA-Lewis Research Center development efforts is presented.

  20. Multiscale probabilistic modeling of a crack bridge in glass fiber reinforced concrete

    Rypla R.

    2017-06-01

    Full Text Available The present paper introduces a probabilistic approach to simulating the crack bridging effects of chopped glass strands in cement-based matrices and compares it to a discrete rigid body spring network model with semi-discrete representation of the chopped strands. The glass strands exhibit random features at various scales, which are taken into account by both models. Fiber strength and interface stress are considered as random variables at the scale of a single fiber bundle while the orientation and position of individual bundles with respect to a crack plane are considered as random variables at the crack bridge scale. At the scale of the whole composite domain, the distribution of fibers and the resulting number of crack-bridging fibers is considered. All the above random effects contribute to the variability of the crack bridge performance and result in size-dependent behavior of a multiply cracked composite.

  1. The use of maleic anhydride-modified polypropylene for performance enhancement in continuous glass fiber-reinforced polypropylene composites

    Rijsdijk, H.A.; Contant, M.; Peijs, A.A.J.M.; Miravete, A.

    1993-01-01

    The influence of maleic anhydride-modified polypropylene (m-PP) on static mech. properties of continuous glass fiber-reinforced polypropylene (PP) composites was studied. M-PP was added to the PP homopolymer to improve the adhesion between the matrix and the glass fiber. Three-point bending tests

  2. Characterization of BG28 and KG3 filter glass for Drive Diagnostic Attenuators

    Page, R H; Weiland, T; Folta, J

    2007-11-30

    BG28 and KG3 filter glasses were tested for use as attenuators in the NIF drive diagnostic (DrD) systems. Tests were performed in the Optical Sciences Laser facility with a 351 nm, 2-step, 3-nsec pulse at fluences ranging up to {approx} 1 J/cm{sup 2}. Single-shot measurements showed no solarization when the samples were allowed to relax for a week after exposure. KG3 filters exhibited no luminescence and no transient pulse distortion. BG28 filters luminesced appreciably and imposed a 'droop' (similar to 'square-pulse distortion') on the signals. The droop parameter is estimated at 0.50 {+-} 0.11 cm{sup 2}/J. Droop is explained in terms of known copper-doped-glass spectroscopy and kinetics (buildup of triplet-state populations, with excited-state absorption). Simulation of the distortion ({approx}1.6%) expected on a 1.8 MJ Haan pulse led to a minor redesign of the Drive Diagnostic with reduced fluence on the BG28 filters to reduce the droop distortion to 0.5%.

  3. Breaking the glass ceiling: hollow OmniGuide fibers

    Johnson, Steven G.; Ibanescu, Mihai; Skorobogatiy, Maksim A.; Weisberg, Ori; Engeness, Torkel D.; Soljacic, Marin; Jacobs, Steven A.; Joannopoulos, John D.; Fink, Yoel

    2002-04-01

    We argue that OmniGuide fibers, which guide light within a hollow core by concentric multilayer films having the property of omnidirectional reflection, have the potential to lift several physical limitations of silica fibers. We show how the strong confinement in OmniGuide fibers greatly suppresses the properties of the cladding materials: even if highly lossy and nonlinear materials are employed, both the intrinsic losses and nonlinearities of silica fibers can be surpassed by orders of magnitude. This feat, impossible to duplicate in an index-guided fiber with existing materials, would open up new regimes for long-distance propagation and dense wavelength-division multiplexing (DWDM). The OmniGuide-fiber modes bear a strong analogy to those of hollow metallic waveguides; from this analogy, we are able to derive several general scaling laws with core radius. Moreover, there is strong loss discrimination between guided modes, depending upon their degree of confinement in the hollow core: this allows large, ostensibly multi-mode cores to be used, with the lowest-loss TE01 mode propagating in an effectively single-mode fashion. Finally, because this TE01 mode is a cylindrically symmetrical ('azimuthally' polarized) singlet state, it is immune to polarization-mode dispersion (PMD), unlike the doubly-degenerate linearly-polarized modes in silica fibers that are vulnerable to birefringence.

  4. Optical and electrical characterizations of multifunctional silver phosphate glass and polymer-based optical fibers.

    Rioux, Maxime; Ledemi, Yannick; Morency, Steeve; de Lima Filho, Elton Soares; Messaddeq, Younès

    2017-03-03

    In recent years, the fabrication of multifunctional fibers has expanded for multiple applications that require the transmission of both light and electricity. Fibers featuring these two properties are usually composed either of a single material that supports the different characteristics or of a combination of different materials. In this work, we fabricated (i) novel single-core step-index optical fibers made of electrically conductive AgI-AgPO 3 -WO 3 glass and (ii) novel multimaterial fibers with different designs made of AgI-AgPO 3 -WO 3 glass and optically transparent polycarbonate and poly (methyl methacrylate) polymers. The multifunctional fibers produced show light transmission over a wide range of wavelengths from 500 to 1000 nm for the single-core fibers and from 400 to 1000 nm for the multimaterial fibers. Furthermore, these fibers showed excellent electrical conductivity with values ranging between 10 -3 and 10 -1  S·cm -1 at room temperature within the range of AC frequencies from 1 Hz to 1 MHz. Multimodal taper-tipped fibre microprobes were then fabricated and were characterized. This advanced design could provide promising tools for in vivo electrophysiological experiments that require light delivery through an optical core in addition to neuronal activity recording.

  5. UV Blocking Glass: Low Cost Filters for Visible Light Photocatalytic Assessment

    Charles W. Dunnill

    2014-01-01

    Full Text Available A number of commercially available art protection products have been compared and assessed for their suitability as UV blocking filters in the application of “visible light” photocatalytic research. Many groups claiming visible light photocatalytic success employ filters to block out stray UV radiation in order to justify that their photocatalysts are indeed visible light photocatalysts and not UV light photocatalysts. These filters come in varying degrees of ability and price and many authors fail to correctly characterise their filters in individual papers. The use of effective filters to prevent both false positive and false negative results is important to maintain scientific rigor and create accurate understanding of the subject. The optimum UV filter would have the highest UV blocking properties (<390 nm and simultaneously the highest visible light transmission (390–750 nm. Single and double layers of each of the glass products were assessed as well as laminate products. The conclusions show an inexpensive and highly effective setup for the conduction of visible light photochemistry that should be incorporated as a standard part in any researcher’s work where the claim of visible light activity is made.

  6. Tunable radio-frequency photonic filter based on an actively mode-locked fiber laser.

    Ortigosa-Blanch, A; Mora, J; Capmany, J; Ortega, B; Pastor, D

    2006-03-15

    We propose the use of an actively mode-locked fiber laser as a multitap optical source for a microwave photonic filter. The fiber laser provides multiple optical taps with an optical frequency separation equal to the external driving radio-frequency signal of the laser that governs its repetition rate. All the optical taps show equal polarization and an overall Gaussian apodization, which reduces the sidelobes. We demonstrate continuous tunability of the filter by changing the external driving radio-frequency signal of the laser, which shows good fine tunability in the operating range of the laser from 5 to 10 GHz.

  7. Application of activated carbon fiber to a filter used for airborne radioiodine sampling

    Kato, Shohei; Murata, Mikio; Yoshikazu, Yoshida

    1988-01-01

    An airborne radioiodine sampling filter is required to have low pressure drop, mechanical strength enough to a practical use and high collection efficiency under high relative humidity(RH). To develop a filter to meet the requirements, the influences of impregnation amount of triethylenediamin(TEDA) on the collection efficiencies for methyl iodide and the reaction rates were investigated for several kinds of activated carbon fiber varied in specific surface area, pore diameter, etc. Silver silica gel(Sut Chemi, AC6120), silver zeolite(CTI Nuc., AgX Type III), silver alumina(Hitachi Co.) and granular activated charcoal were also examined for comparison. A new type filter made of activated carbon fiber (ACF filter) was developed based on the above experimental results. The ACF filter was examined for the pressure drop by the filter and collection efficiency for methyl iodide being compared with other types of filters such as an activated charcoal cartridge (ACC) and an activated charcoal filter paper (ACP)

  8. THE PROPERTIES OF GUIDED ELECTROMAGNETIC FIELD MODES ON THE GaAs-BASED FIBER GLASS AND LASERS

    Mustafa TEMİZ

    1999-03-01

    Full Text Available On the lasers or fiber optic communication electromagnetic waves are transmitted by confining and guiding between special layer's or fiber glass respectively. It is desired that electric and magnetic waves are in the active region of the lasers and in the core of the fiber glass. It is obtained by making more larger the of refractive index of the regions. On this work, the behavior and varying of the electric and magnetic waves and the effects on the electromagnetic waves in the fiber glass and lasers are investigated.

  9. High-efficiency ytterbium-free erbium-doped all-glass double cladding silicate glass fiber for resonantly-pumped fiber lasers.

    Qiang, Zexuan; Geng, Jihong; Luo, Tao; Zhang, Jun; Jiang, Shibin

    2014-02-01

    A highly efficient ytterbium-free erbium-doped silicate glass fiber has been developed for high-power fiber laser applications at an eye-safe wavelength near 1.55 μm. Our preliminary experiments show that high laser efficiency can be obtained from a relatively short length of the gain fiber when resonantly pumped at 1535 nm in both core- and cladding-pumping configurations. With a core-pumping configuration as high as 75%, optical-to-optical efficiency and 4 W output power were obtained at 1560 nm from a 1 m long gain fiber. When using a cladding-pumping configuration, approximately 13 W output power with 67.7% slope efficiency was demonstrated from a piece of 2 m long fiber. The lengths of silicate-based gain fiber are much shorter than their silica-based counterparts used in other experiments, which is significantly important for high-power narrow-band and/or pulsed laser applications.

  10. Scalable air cathode microbial fuel cells using glass fiber separators, plastic mesh supporters, and graphite fiber brush anodes

    Zhang, Xiaoyuan

    2011-01-01

    The combined use of brush anodes and glass fiber (GF1) separators, and plastic mesh supporters were used here for the first time to create a scalable microbial fuel cell architecture. Separators prevented short circuiting of closely-spaced electrodes, and cathode supporters were used to avoid water gaps between the separator and cathode that can reduce power production. The maximum power density with a separator and supporter and a single cathode was 75±1W/m3. Removing the separator decreased power by 8%. Adding a second cathode increased power to 154±1W/m3. Current was increased by connecting two MFCs connected in parallel. These results show that brush anodes, combined with a glass fiber separator and a plastic mesh supporter, produce a useful MFC architecture that is inherently scalable due to good insulation between the electrodes and a compact architecture. © 2010 Elsevier Ltd.

  11. Achieving Hydrogen Storage Goals through High-Strength Fiber Glass - Final Technical Report

    Li, Hong [PPG Industries, Inc., Cheswick, PA (United States); Johnson, Kenneth I. [PPG Industries, Inc., Cheswick, PA (United States); Newhouse, Norman L. [PPG Industries, Inc., Cheswick, PA (United States)

    2017-06-05

    Led by PPG and partnered with Hexagon Lincoln and Pacific Northwest National Laboratory (PNNL), the team recently carried out a project “Achieving Hydrogen Storage Goals through High-Strength Fiber Glass”. The project was funded by DOE’s Fuel Cell Technologies office within the Office of Energy Efficiency and Renewable Energy, starting on September 1, 2014 as a two-year project to assess technical and commercial feasibilities of manufacturing low-cost, high-strength glass fibers to replace T700 carbon fibers with a goal of reducing the composite total cost by 50% of the existing, commercial 700 bar hydrogen storage tanks used in personal vehicles.

  12. Effect of fabric structure and polymer matrix on flexural strength, interlaminar shear stress, and energy dissipation of glass fiber-reinforced polymer composites

    We report the effect of glass fiber structure and the epoxy polymer system on the flexural strength, interlaminar shear stress (ILSS), and energy absorption properties of glass fiber-reinforced polymer (GFRP) composites. Four different GFRP composites were fabricated from two glass fiber textiles of...

  13. Chemically etched sharpened tip of transparent crystallized glass fibers with nonlinear optical Ba2TiSi2O8 nanocrystals

    Enomoto, Itaru; Benino, Yasuhiko; Komatsu, Takayuki; Fujiwara, Takumi

    2007-01-01

    Glass fibers with a diameter of ∼100 μm are drawn by just pulling up melts of 40BaO·20TiO 2 ·40SiO 2 glass, and transparent crystallized glass fibers consisting of nonlinear optical fresnoite Ba 2 TiSi 2 O 8 nanocrystals (particle size: ∼100-200 nm) are fabricated by crystallization of glass fibers. Precursor glass fibers and nanocrystallized glass fibers are etched chemically using a meniscus method, in which an etching solution of 0.1wt%-HF/hexane is used. Glass fibers with sharpened tips (e.g., the taper length is ∼L=200 μm and the tip angle is ∼θ=23deg) are obtained. It is found that etched nanocrystallized glass fibers also have sharpened tips (L=50 μm, θ=80deg). Compared with precursor glass fibers, nanocrystallized glass fibers show a high resistance against chemical etching in a 0.1 wt%HF solution. Although sharpened tips in nanocrystallized glass fibers do not have nanoscaled apertures, the present study suggests that nanocrystallized glass fibers showing second harmonic generations would have a potential for fiber-type light control optical devices. (author)

  14. Ultrasound enhanced 50 Hz plasma treatment of glass-fiber-reinforced polyester at atmospheric pressure

    Kusano, Yukihiro; Norrman, Kion; Singh, Shailendra Vikram

    2013-01-01

    Glass-fiber-reinforced polyester (GFRP) plates are treated using a 50Hz dielectric barrier discharge at a peak-to-peak voltage of 30 kV in helium at atmospheric pressure with and without ultrasonic irradiation to study adhesion improvement. The ultrasonic waves at the fundamental frequency...

  15. Gliding arc surface treatment of glass-fiber-reinforced polyester enhanced by ultrasonic irradiation

    Kusano, Yukihiro; Norrman, Kion; Drews, Joanna Maria

    2011-01-01

    . The efficiency of such a plasma treatment at atmospheric pressure can be further improved by ultrasonic irradiation onto the surface during the treatment. In the present work glass fiber reinforced polyester (GFRP) plates are treated using an atmospheric pressure gliding arc with and without ultrasonic...

  16. Experimental Investigation of Thermal Properties in Glass Fiber Reinforced with Aluminium

    Irudaya raja, S. Joseph; Vinod Kumar, T.; Sridhar, R.; Vivek, P.

    2017-03-01

    A test method of a Guarded heat flow meter are used to measure the thermal conductivity of glass fiber and filled with a aluminum powder epoxy composites using an instrument in accordance with ASTM. This experimental study reveals that the incorporation of aluminum and glass fiber reinforced results in enhancement of thermal conductivity of epoxy resin and thereby improves its heat transfer capability. Fiber metal laminates are good candidates for advanced automobile structural applications due to their high categorical mechanical and thermal properties. The most consequential factor in manufacturing of these laminates is the adhesive bonding between aluminum and FRP layers. Here several glass-fiber reinforced aluminum were laminates with different proportion of bonding adhesion were been manufactured. It was observed that the damage size is more preponderant in laminates with poor interfacial adhesion compared to that of laminates with vigorous adhesion between aluminum and glass layers numerically calculated ones and it is found that the values obtained for various composite models using experimental testing method.

  17. Methods for evaluating tensile and compressive properties of plastic laminates reinforced with unwoven glass fibers

    Karl Romstad

    1964-01-01

    Methods of obtaining strength and elastic properties of plastic laminates reinforced with unwoven glass fibers were evaluated using the criteria of the strength values obtained and the failure characteristics observed. Variables investigated were specimen configuration and the manner of supporting and loading the specimens. Results of this investigation indicate that...

  18. Experimental study of fiber-glass plastic work pieces contour milling

    Trushin, N. N.; Lisitsin, V. N.

    2018-03-01

    The article represents the results of study of cut and feed speed influence on wear of monolithic hard alloy end milling cutter during cutting of foiled fiber-glass plastic sheets, used for printed-circuit boards’ production. The peculiarities and problems of cutting layered materials are described. The most effective feed and cut speed values are determined by cutter wear analysis.

  19. hybrid effect on the mechanical properties of sisal fiber and e-glass

    cles was added and the “mix” was vigorously stirred and poured into a mould. Appropriate quantities of fibers (sisal or E-glass) were im- pregnated in the “resin mix” which ultimately cured to give a solid laminate. 2.3. Tensile test. Standard tensile specimens were cut from the hybrid and non-hybrid composite lami-. Nigerian ...

  20. Structural and optical properties of antimony-germanate-borate glass and glass fiber co-doped Eu3+ and Ag nanoparticles.

    Zmojda, Jacek; Kochanowicz, Marcin; Miluski, Piotr; Baranowska, Agata; Pisarski, Wojciech A; Pisarska, Joanna; Jadach, Renata; Sitarz, Maciej; Dorosz, Dominik

    2018-08-05

    In the paper analysis of structural and luminescent properties of antimony-germanate-borate glasses and glass fiber co-doped with 0.6AgNO 3 /0.2Eu 2 O 3 are presented. Heat treatment of the fabricated glass and optical fiber (400 °C, 12 h) enabled to obtain Ag nanoparticles (NPs) with average size 30-50 nm on their surface. It has been proofed that silver ions migrate to the glass surface, where they are reduced to Ag 0 nanoparticles. Simultaneously, FTIR analysis showed that heat treatment of the glass and optical fiber increases the local symmetry of the Eu 3+ site. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. Application of Cu{sub 2}O-doped phosphate glasses for bandpass filter

    Elhaes, H. [Physics Department, Faculty of Women for Arts, Science and Education, Ain Shams University, 11757 Cairo (Egypt); Attallah, M., E-mail: m_atallah94@yahoo.com [Basic Science Department, Higher Technological Institute, 10th of Ramadan City (Egypt); Elbashar, Y.; El-Okr, M. [Physics Department, Faculty of Science, Al Azhar University, Cairo (Egypt); Ibrahim, M. [Spectroscopy Department, National Research Centre, 12311 Dokki, Cairo (Egypt)

    2014-09-15

    Phosphate glasses doped with copper ions having general composition 42P{sub 2}O{sub 5}–39ZnO–(18−x) Na{sub 2}O–1CaO–xCu{sub 2}O [x=2, 4, 6, 8, 10 mol%] were prepared using a conventional melt-quench technique. Physical and chemical properties of the glasses were investigated using X-ray diffraction technique and UV–visible optical absorption. The density was measured by Archimedes' method, and molar volume (V{sub M}) was calculated. It is found that density and molar volume show opposite trend by increasing Cu{sub 2}O content. Absorbance and transmittance at the normal incidence are measured by a spectrophotometer in the spectral range of 190–1100 nm. Analyses of the obtained results were considered in the frame of current theories. Absorption data were used for absorption coefficient, the optical band gap (E{sub opt}), the cutoff in UV and IR bands to the bandpass filter, which confirmed the optical properties of this type of filter. E{sub opt} values for different glass samples are found to decrease with increasing Cu{sub 2}O content.

  2. Weighted finite impulse response filter for chromatic dispersion equalization in coherent optical fiber communication systems

    Zeng, Ziyi; Yang, Aiying; Guo, Peng; Feng, Lihui

    2018-01-01

    Time-domain CD equalization using finite impulse response (FIR) filter is now a common approach for coherent optical fiber communication systems. The complex weights of FIR taps are calculated from a truncated impulse response of the CD transfer function, and the modulus of the complex weights is constant. In our work, we take the limited bandwidth of a single channel signal into account and propose weighted FIRs to improve the performance of CD equalization. The key in weighted FIR filters is the selection and optimization of weighted functions. In order to present the performance of different types of weighted FIR filters, a square-root raised cosine FIR (SRRC-FIR) and a Gaussian FIR (GS-FIR) are investigated. The optimization of square-root raised cosine FIR and Gaussian FIR are made in term of the bit rate error (BER) of QPSK and 16QAM coherent detection signal. The results demonstrate that the optimized parameters of the weighted filters are independent of the modulation format, symbol rate and the length of transmission fiber. With the optimized weighted FIRs, the BER of CD equalization signal is decreased significantly. Although this paper has investigated two types of weighted FIR filters, i.e. SRRC-FIR filter and GS-FIR filter, the principle of weighted FIR can also be extended to other symmetric functions super Gaussian function, hyperbolic secant function and etc.

  3. Analysis of the mechanical and thermal properties of jute and glass fiber as reinforcement epoxy hybrid composites

    Braga, R.A., E-mail: roney.braga@fiat.com.br [FIAT Automóveis S.A., Teardown, CEP 32530-000 Betim, MG (Brazil); Magalhaes, P.A.A., E-mail: pamerico@pucminas.br [PUC—MINAS, Instituto Politécnico, CEP 30535-610 Belo Horizonte, MG (Brazil)

    2015-11-01

    This work describes the study to investigate and compare the mechanical and thermal properties of raw jute and glass fiber reinforced epoxy hybrid composites. To improve the mechanical properties, jute fiber was hybridized with glass fiber. Epoxy resin, jute and glass fibers were laminated in three weight ratios (69/31/0, 68/25/7 and 64/18/19) respectively to form composites. The tensile, flexural, impact, density, thermal and water absorption tests were carried out using hybrid composite samples. This study shows that the addition of jute fiber and glass fiber in epoxy, increases the density, the impact energy, the tensile strength and the flexural strength, but decreases the loss mass in function of temperature and the water absorption. Morphological analysis was carried out to observe fracture behavior and fiber pull-out of the samples using scanning electron microscope. - Highlights: • The work is the study of the mechanical of raw jute and glass fiber with epoxy resin. • The mechanical properties increased with more proportions of glass fibers. • The density of E69-J31-V0 was the lower. • The flexural strength did not have a significant increase. • The water absorption of E69-J31-V0 was the best.

  4. Influence of thermal cycling on flexural properties of composites reinforced with unidirectional silica-glass fibers.

    Meriç, Gökçe; Ruyter, I Eystein

    2008-08-01

    The purpose was to investigate the effect of water storage and thermal cycling on the flexural properties of differently sized unidirectional fiber-reinforced composites (FRCs) containing different quantities of fibers. The effect of fiber orientation on the thermal expansion of FRCs as well as how the stresses in the composites can be affected was considered. An experimental polymeric base material was reinforced with silica-glass fibers. The cleaned and silanized fibers were sized with either linear PBMA-size or crosslinked PMMA-size. For the determination of flexural properties and water uptake, specimens were processed with various quantities of differently sized unidirectional fibers. Water uptake of FRC was measured. Water immersed specimens were thermally cycled for 500 and 12,000 cycles (5 degrees C/55 degrees C). Flexural properties of "dry" and wet specimens with and without thermal cycling were determined by a three-point bending test. The linear coefficients of thermal expansion (LCTE) for FRC samples with different fiber orientations were determined using a thermomechanical analyzer. Water uptake of the FRC specimens increased with a decrease in fiber content of the FRC. Flexural properties of FRCs improved with increasing fiber content, whereas the flexural properties were not influenced significantly by water and thermal cycling. Fiber orientation had different effects on LCTE of FRCs. Unidirectional FRCs had two different LCTE in longitudinal and transverse directions whereas bidirectional FRCs had similar LCTE in two directions and a higher one in the third direction. The results of the study suggest that the surface-treated unidirectional silica-glass FRC can be used for long-term clinical applications in the oral cavity.

  5. Synthesis of biodegradable polymer/glass fiber composite by EB irradiation and its biodegradability

    Yoshii, Fumio; Doam Thi The

    2006-01-01

    A composite was synthesized by irradiation of poly (butylene succinate), PBS and glass fiber (GF) in the presence of a polyfunctional monomer, trimethallyl isocyanurate (TMAIC), which accelerates gel formation of the matrix (PBS). The highest gel fraction was achieved at 1% concentration of TMAIC at the dose level of 200 kGy. Mechanical properties of the composites were highly dependent on the gel fraction of the polymer and volume fraction of glass fiber reinforcement in the composite. Optimal conditions to synthesize a PBS/GF composite reaching maximum value of bending strength were 1% TMAIC, 67% fiber volume fraction, and radiation dose of 200 kGy. These synthesized PBS/GF composites can be degraded by enzymes produced by the microorganism population in soil. (author)

  6. Effective thermal conductivity of glass-fiber board and blanket standard reference materials

    Smith, D.R.; Hust, J.G.

    1983-01-01

    This chapter reports on measurements of effective thermal conductivity performed on a series of specimens of glass-fiber board and glass-fiber blanket. Explains that measurements of thermal conductivity were conducted as a function of temperature from 85 to 360 K, of temperature difference with T=10 to 100 K, of bulk density from 11 to 148 kg/m 3 and for nitrogen, argon, and helium inter-fiber fill gases at pressures from atmospheric to high vacuum. Analyzes and compares results with values from the published literature and National Bureau of Standards (NBS) certification data for similar material. Gives polynomial expressions for the functional relation between conductivity, temperature, and density for board and for blanket

  7. Machinability of glass fiber reinforced plastic (GFRP) composite ...

    This paper deals with the study of machinability of GFRP composite tubes of different fiber orientation angle vary from 300 to 900. Machining studies were carried out on an all geared lathe using three different cutting tools: namely Carbide (K-20), Cubic Boron Nitride (CBN) and Poly-Crystalline Diamond (PCD). Experiments ...

  8. A simple gold-coated microstructure fiber polarization filter in two communication windows

    Feng, Xinxing; Li, Shuguang; Du, Huijing; Zhang, Yinan; Liu, Qiang

    2018-03-01

    A polarization filter is designed at two communication windows of 1310 and 1550 nm based on microstructured optical fiber. The model has four large diameter air holes and two gold-coated air holes. The influence of the geometrical parameters of the photonic crystal fiber on the performance of the polarization filter is analyzed by the finite element method. The numerical simulation shows that when the fiber length is 300 μm, the corresponding extinction ratio is 209.7 dB and 179.8 dB, the bandwidth of extinction ratio (ER) better than 20 dB is 150 nm and 350 nm at the communication wavelength of 1310 nm and 1550 nm.

  9. Tunable and reconfigurable multi-tap microwave photonic filter based on dynamic Brillouin gratings in fibers.

    Sancho, J; Primerov, N; Chin, S; Antman, Y; Zadok, A; Sales, S; Thévenaz, L

    2012-03-12

    We propose and experimentally demonstrate new architectures to realize multi-tap microwave photonic filters, based on the generation of a single or multiple dynamic Brillouin gratings in polarization maintaining fibers. The spectral range and selectivity of the proposed periodic filters is extensively tunable, simply by reconfiguring the positions and the number of dynamic gratings along the fiber respectively. In this paper, we present a complete analysis of three different configurations comprising a microwave photonic filter implementation: a simple notch-type Mach-Zehnder approach with a single movable dynamic grating, a multi-tap performance based on multiple dynamic gratings and finally a stationary grating configuration based on the phase modulation of two counter-propagating optical waves by a common pseudo-random bit sequence (PRBS).

  10. Fine-filter method for Raman lidar based on wavelength division multiplexing and fiber Bragg grating.

    Wang, Jun; Zheng, Jiao; Lu, Hong; Yan, Qing; Wang, Li; Liu, Jingjing; Hua, Dengxin

    2017-11-01

    Atmospheric temperature is one of the important parameters for the description of the atmospheric state. Most of the detection approaches to atmospheric temperature monitoring are based on rotational Raman scattering for better understanding atmospheric dynamics, thermodynamics, atmospheric transmission, and radiation. In this paper, we present a fine-filter method based on wavelength division multiplexing, incorporating a fiber Bragg grating in the visible spectrum for the rotational Raman scattering spectrum. To achieve high-precision remote sensing, the strong background noise is filtered out by using the secondary cascaded light paths. Detection intensity and the signal-to-noise ratio are improved by increasing the utilization rate of return signal form atmosphere. Passive temperature compensation is employed to reduce the temperature sensitivity of fiber Bragg grating. In addition, the proposed method provides a feasible solution for the filter system with the merits of miniaturization, high anti-interference, and high stability in the space-based platform.

  11. Tribological analysis of nano clay/epoxy/glass fiber by using Taguchi’s technique

    Senthil Kumar, M.S.; Mohana Sundara Raju, N.; Sampath, P.S.; Vivek, U.

    2015-01-01

    Highlights: • To study the tribological property of modified epoxy with and without E glass fiber. • To analyze the tribological property of specimens by Taguchi’s technique and ANOVA. • To investigate the surface morphology of test specimens with SEM. - Abstract: In this work, a detailed analysis was performed to profoundly study the tribological property of various nano clay (Cloisite 25A) loaded epoxy, with and without inclusion of E-glass fiber using Taguchi’s technique. For this purpose, the test samples were prepared according to the ASTM standard, and the test was carried out with the assistance of pin-on-disk machine. To proceed further, L 25 orthogonal array was constructed to evaluate the tribological property with four control variables such as filler content, normal load, sliding velocity and sliding distance at each level. The results indicated that the combination of factors greatly influenced the process to achieve the minimum wear and coefficient of friction. Overall, the experiment results depicted least wear and friction coefficient for fiber reinforced laminates. In the same way, appreciable wear and friction coefficient was noted for without fiber laminates. Additionally, the SN ratio results too exhibited the similar trend. Moreover, ANOVA analysis revealed that the fiber inclusion on laminates has lesser contribution on coefficient of friction and wear when compared to without fiber laminates. At last, the microstructure behavior of the test samples was investigated with an assistance of Scanning Electron Microscope (SEM) to analyze the surface morphology

  12. Second Order Harmonics Suppression With Glass Filters for Synchrotron UV Radiation Calibration Measurement

    Burattini, E; Gambicorti, L; Malvezzi, F; Marcelli, A; Monti, F; Pace, E

    2005-01-01

    This development is the latest result of the cooperation between the National Laboratories of Frascati and the Department of Astronomy and Space Science of the University of Florence to improve the capabilities of the existing DXR-2 beam line at the DAΦNE-LIGHT laboratories. This collaboration has assessed a new facility in order to characterize optics and sensors in a wide spectral range (ranging from VUV to IR). Previous measurements [1] have highlighted some limitations in the present setup, as higher signal levels due to the diffracted radiation of the grating in the second order have to be removed to allow an accurate detection. In this work a glass filter is used to remove such spurious signal present in the spectral region with λ > 360 nm. The characteristics of the filter and its application to the optical system used to measure the sensitivity of a diamond-based photoconductor have been discussed.

  13. The applicability of alkaline-resistant glass fiber in cement mortar of road pavement: Corrosion mechanism and performance analysis

    Qin Xiaochun

    2017-11-01

    Full Text Available The main technical requirements of road pavement concrete are high flexural strength and fatigue durability. Adding glass fiber into concrete could greatly increase flexural strength and wearing resistance of concrete. However, glass fiber has the great potential of corrosion during the cement hydration, which will directly affect the long-term performance and strength stability. In this paper, accelerated corrosion experiments have been done to find out the corrosion mechanism and property of alkali-resistant glass fiber in cement mortar. The applicability and practicability of alkaline-resistant glass fiber in road concrete have been illustrated in the analysis of flexural strength changing trend of cement mortar mixed with different proportions of activated additives to protect the corrosion of glass fiber by cement mortar. The results have shown that a 30% addition of fly ash or 10% addition of silica fume to cement matrix could effectively improve the corrosion resistance of alkali-resistant glass fiber. The optimal mixing amount of alkali-resistant glass fiber should be about 1.0 kg/m3 in consideration of ensuring the compressive strength of reinforced concrete in road pavement. The closest-packing method has been adopted in the mixture ratio design of alkali-resistant glass fiber reinforced concrete, not only to reduce the alkalinity of the cement matrix through large amount addition of activated additives but also to greatly enhance the flexural performance of concrete with the split pressure ratio improvement of 12.5–16.7%. The results suggested a prosperous application prospect for alkaline-resistant glass fiber reinforced concrete in road pavement.

  14. Structural Laminate Aluminum-Glass-Fiber Materials 1441-Sial

    Shestov, V. V.; Antipov, V. V.; Senatorova, O. G.; Sidel'nikov, V. V.

    2014-01-01

    The structure, composition and set of properties of specimens and components, and some parameters of the process of production of a promising FML class of metallic polymers based on sheets of high-modulus ( E 79 GPa) alloy 1441 with reduced density ( d 2.6 g/cm3) and an optimized glued prepreg reinforced with fibers of high-strength high-modulus VMPglass are described. Results of fire and fatigue tests of a promising 1441-SIAL structural laminate are presented.

  15. Effect of Different Fillers on Adhesive Wear Properties of Glass Fiber Reinforced Polyester Composites

    E. Feyzullahoğlu

    2017-12-01

    Full Text Available Polymeric composites are used for different aims as substitute of traditional materials such as metals; due to their improved strength at small specific weight. The fiber reinforced polymer (FRP composite material consists of polymeric matrix and reinforcing material. Polymeric materials are commonly reinforced with synthetic fibers such as glass and carbon. The glass fiber reinforced polyester (GFRP composites are used with different filler materials. The aim of this study is to investigate the effects of different filler materials on adhesive wear behavior of GFRP. In this experimental study; polymetilmetacrilat (PMMA, Glass beads (GB and Glass sand (GS were used as filling material in GFRP composite samples. The adhesive wear behaviors of samples were carried out using ball on disc type tribometer. The friction force and coefficient of friction were measured during the test. The volume loss and wear rate values of samples were calculated according to test results. Barcol hardness values of samples were measured. The densities of samples were measured. Results show that the wear resistance of GB filled GFRP composite samples was much more than non-filled and PMMA filled GFRP composite samples.

  16. Study on processing parameters of glass cutting by nanosecond 532 nm fiber laser

    Wang, Jin; Gao, Fan; Xiong, Baoxing; Zhang, Xiang; Yuan, Xiao

    2018-03-01

    The processing parameters of soda-lime glass cutting with several nanosecond 532 nm pulsed fiber laser are studied in order to obtain sufficiently large ablation rate and better processing quality. The influences of laser processing parameters on effective cutting speed and cutting quality of 1 2 mm thick soda-lime glass are studied. The experimental results show that larger laser pulse energy will lead to higher effective cutting speed and larger maximum edge collapse of the front side of the glass samples. Compared with that of 1.1 mm thick glass samples, the 2.0 mm thick glass samples is more difficult to cut. With the pulse energy of 51.2 μJ, the maximum edge collapse is more than 200 μm for the 2.0 mm thick glass samples. In order to achieve the high effective cutting speed and good cutting quality at the same time, the dual energy overlapping method is used to obtain the better cutting performance for the 2.0 mm thick glass samples, and the cutting speed of 194 mm/s and the maximum edge collapse of less than 132 μm are realized.

  17. Glass fiber -reinforced plastic tapered poles for transmission and distribution lines: development and experimental study

    Ibrahim, S.; Burachysnsky, V.; Polyzois, D.

    1999-01-01

    A research project to develop lightweight poles for use in power transmission and distribution lines and involving the use of glass fiber-reinforced plastic using the filament winding process is described. Twelve full scale specimen poles were designed, fabricated and subjected to cantilever bending to test failure modes. The test parameters included fiber orientation, ratio of longitudinal-to-circumferential fiber, and the number of layers. Results showed that local buckling was the most dominant failure mode, attributable to the high radius-to-thickness ratio of the specimen poles. Overall, however, these fiber-reinforced plastic poles compared favourably to wooden poles in carrying capacity with significant weight reduction. Lateral displacement at ultimate loads did not exceed the acceptable limit of 10 per cent of the specimen free length. 7 refs., 3 tabs., 2 figs

  18. Influence of the curing cycles on the fatigue performance of unidirectional glass fiber reinforced epoxy composites

    Hüther, Jonas; Brøndsted, Povl

    2016-01-01

    During the manufacturing process of fiber reinforced polymers the curing reaction of the resin results in shrinkage of the resin and introduces internal stresses in the composites. When curing at higher temperatures in order to shorten up the processing time, higher curing stresses and thermal...... to different levels of internal stresses. The mechanical properties, static strength and fatigue life time, are measured in three different directions of the material, i.e. the fiber direction, 0°, the 30° off axis direction, and the 90° direction transverse to the fiber direction. It is experimentally...... demonstrated that the resulting residual stresses barely influences the quasi-static mechanical properties of reinforced glass-fiber composites. It is found that the fatigue performance in the 0° direction is significantly influenced by the internal stresses, whereas the fatigue performance in the off axes...

  19. A wavelength-tunable fiber laser using a novel filter based on a compound interference effect

    Zou, Hui; Lou, Shuqin; Su, Wei; Han, Bolin; Shen, Xiao

    2015-01-01

    A wavelength-tunable erbium-doped fiber laser is proposed and experimentally demonstrated by using a novel filter which is formed from a 2  ×  2 3 dB multimode coupler incorporating a segment of polarization maintaining fiber (PMF). By using the filter with 2.1 m lengths of PMF in a ring fiber laser, a stable single wavelength lasing is obtained experimentally. Its 3 dB bandwidth is less than 0.0147 nm and the side mode suppression ratio (SMSR) is higher than 58.91 dB. Experimental results demonstrate that mode competition can be effectively suppressed and the SMSR can be improved due to the compound interference effect aroused by the novel filter. Meanwhile the stability of the output lasing can be enhanced. By appropriately adjusting the polarization controllers (PCs), the output lasing wavelength can be tuned from 1563.51 to 1568.21 nm. This fiber laser has the advantage of a simple structure and stable operation at room temperature.

  20. Joint Multi-Fiber NODDI Parameter Estimation and Tractography using the Unscented Information Filter

    Yogesh eRathi

    2016-04-01

    Full Text Available Tracing white matter fiber bundles is an integral part of analyzing brain connectivity. An accurate estimate of the underlying tissue parameters is also paramount in several neuroscience applications. In this work, we propose to use a joint fiber model estimation and tractography algorithm that uses the NODDI (neurite orientation dispersion diffusion imaging model to estimate fiber orientation dispersion consistently and smoothly along the fiber tracts along with estimating the intracellular and extracellular volume fractions from the diffusion signal. While the NODDI model has been used in earlier works to estimate the microstructural parameters at each voxel independently, for the first time, we propose to integrate it into a tractography framework. We extend this framework to estimate the NODDI parameters for two crossing fibers, which is imperative to trace fiber bundles through crossings as well as to estimate the microstructural parameters for each fiber bundle separately. We propose to use the unscented information filter (UIF to accurately estimate the model parameters and perform tractography. The proposed approach has significant computational performance improvements as well as numerical robustness over the unscented Kalman filter (UKF. Our method not only estimates the confidence in the estimated parameters via the covariance matrix, but also provides the Fisher-information matrix of the state variables (model parameters, which can be quite useful to measure model complexity. Results from in-vivo human brain data sets demonstrate the ability of our algorithm to trace through crossing fiber regions, while estimating orientation dispersion and other biophysical model parameters in a consistent manner along the tracts.

  1. Fiber optic adaptation of the interference filter photometer SPECTRAN for in-line measurements in PUREX process control

    Buerck, J.; Kraemer, K.; Koenig, W.

    1990-02-01

    The multicomponent version of the interference filter photometer SPECTRAN was adapted by radiation resistant quartz glass optical fibers to in-line flow cells in the aqueous and organic bypass stream of an uranium laboratory extraction column. A combined photometric/electrolytical conductivity measurement allows this modified process instrument to be used as uranium/plutonium in-line monitor in radioactive process streams. By applying a high performance 100 W quartz halogen lamp and suitable light focussing optics the light intensity, attenuated by coupling losses, could be increased to the desired level even when 1000 μm-single strand fibers (2x18 m) were used to transmit the light. In a series of calibration experiments the U(VI)- and U(IV)-extinction coefficients were determined as a function of nitric acid molarity (for U(VI) also in TBP/kerosene). Furthermore the validity of Lambert-Beer's law was examined for both oxidation states at different optical path lengths and nitric acid/electrolytical conductivity calibration functions between 0-100 g/l U(VI) and 0-4 mol/l HNO 3 were set up. (orig./EF) [de

  2. In vitro stimulation of vascular endothelial growth factor by borate-based glass fibers under dynamic flow conditions

    Chen, Sisi; Yang, Qingbo; Brow, Richard K.; Liu, Kun; Brow, Katherine A.; Ma, Yinfa

    2017-01-01

    Bioactive borate glass has been recognized to have both hard and soft tissue repair and regeneration capabilities through stimulating both osteogenesis and angiogenesis. However, the underlying biochemical and cellular mechanisms remain unclear. In this study, dynamic flow culturing modules were designed to simulate the micro-environment near the vascular depletion and hyperplasia area in wound-healing regions, thus to better investigate the mechanisms underlying the biocompatibility and functionality of borate-based glass materials. Glass fibers were dosed either upstream or in contact with the pre-seeded cells in the dynamic flow module. Two types of borate glasses, doped with (1605) or without (13-93B3) CuO and ZnO, were studied along with the silicate-based glass, 45S5. Substantial fiber dissolution in cell culture medium was observed, leading to the release of ions (boron, sodium and potassium) and the deposition of a calcium phosphate phase. Different levels of vascular endothelial growth factor secretion were observed from cells exposed to these three glass fibers, and the copper/zinc containing borate 1605 fibers exhibited the most positive influence. These results indicate that dynamic studies of in vitro bioactivity provide useful information to understand the in vivo response to bioactive borate glasses. - Highlights: • Novel dynamic flow cell culture modules were designed. • Bioactive glass fibers were evaluated for their effects on VEGF secretion. • Borate-based glass fibers stimulate VEGF secretion under dynamic condition. • CuO and ZnO doped borate-based glass fibers stimulate the greatest VEGF release.

  3. In vitro stimulation of vascular endothelial growth factor by borate-based glass fibers under dynamic flow conditions

    Chen, Sisi [Department of Chemistry, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Biomedical Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Yang, Qingbo [Department of Chemistry, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Biomedical Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Single Nanoparticle, Single Cell, and Single Molecule Monitoring, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Brow, Richard K. [Department of Material Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Biomedical Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Liu, Kun [Department of Chemistry, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Single Nanoparticle, Single Cell, and Single Molecule Monitoring, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Brow, Katherine A. [Department of Chemistry, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Ma, Yinfa [Department of Chemistry, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Biomedical Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Single Nanoparticle, Single Cell, and Single Molecule Monitoring, Missouri University of Science and Technology, Rolla, MO 65409 (United States); and others

    2017-04-01

    Bioactive borate glass has been recognized to have both hard and soft tissue repair and regeneration capabilities through stimulating both osteogenesis and angiogenesis. However, the underlying biochemical and cellular mechanisms remain unclear. In this study, dynamic flow culturing modules were designed to simulate the micro-environment near the vascular depletion and hyperplasia area in wound-healing regions, thus to better investigate the mechanisms underlying the biocompatibility and functionality of borate-based glass materials. Glass fibers were dosed either upstream or in contact with the pre-seeded cells in the dynamic flow module. Two types of borate glasses, doped with (1605) or without (13-93B3) CuO and ZnO, were studied along with the silicate-based glass, 45S5. Substantial fiber dissolution in cell culture medium was observed, leading to the release of ions (boron, sodium and potassium) and the deposition of a calcium phosphate phase. Different levels of vascular endothelial growth factor secretion were observed from cells exposed to these three glass fibers, and the copper/zinc containing borate 1605 fibers exhibited the most positive influence. These results indicate that dynamic studies of in vitro bioactivity provide useful information to understand the in vivo response to bioactive borate glasses. - Highlights: • Novel dynamic flow cell culture modules were designed. • Bioactive glass fibers were evaluated for their effects on VEGF secretion. • Borate-based glass fibers stimulate VEGF secretion under dynamic condition. • CuO and ZnO doped borate-based glass fibers stimulate the greatest VEGF release.

  4. CO2-laser-assisted processing of glass fiber-reinforced thermoplastic composites

    Brecher, Christian; Emonts, Michael; Schares, Richard Ludwig; Stimpfl, Joffrey

    2013-02-01

    To fully exploit the potential of fiber-reinforced thermoplastic composites (FRTC) and to achieve a broad industrial application, automated manufacturing systems are crucial. Investigations at Fraunhofer IPT have proven that the use of laser system technology in processing FRTC allows to achieve high throughput, quality, flexibility, reproducibility and out-of-autoclave processing simultaneously. As 90% of the FRP in Europe1 are glass fiber-reinforced a high impact can be achieved by introducing laser-assisted processing with all its benefits to glass fiber-reinforced thermoplastics (GFRTC). Fraunhofer IPT has developed the diode laser-assisted tape placement (laying and winding) to process carbon fiber-reinforced thermoplastic composites (CFRTC) for years. However, this technology cannot be transferred unchanged to process milky transparent GFRTC prepregs (preimpregnated fibers). Due to the short wavelength (approx. 980 nm) and therefore high transmission less than 20% of the diode laser energy is absorbed as heat into non-colored GFRTC prepregs. Hence, the use of a different wave length, e.g. CO2-laser (10.6 μm) with more than 90% laser absorption, is required to allow the full potential of laser-assisted processing of GFRTC. Also the absorption of CO2-laser radiation at the surface compared to volume absorption of diode laser radiation is beneficial for the interlaminar joining of GFRTC. Fraunhofer IPT is currently developing and investigating the CO2-laser-assisted tape placement including new system, beam guiding, process and monitoring technology to enable a resource and energy efficient mass production of GFRP composites, e.g. pipes, tanks, masts. The successful processing of non-colored glass fiber-reinforced Polypropylene (PP) and Polyphenylene Sulfide (PPS) has already been proven.

  5. Evaluation of air jet erosion profiles in metal mesh supported SCR plate catalyst based on glass fiber concentrations

    Rajath, S.; Nandakishora, Y.; Siddaraju, C.; Roy, Sukumar

    2018-04-01

    This paper explains the evaluation of erosion profiles in metal mesh supported SCR plate catalyst structures in which the glass fibers concentration in the catalyst material is considered as prime factor for erosion resistance and mechanical strength. The samples are prepared and tested at the specified and constant conditions like velocity as 30m/s, sand flow rate as 2g/min, average particle diameter 300 µm and all these samples were tested at different angles at impact preferably 15°,30°,45°,60°,75°,and 90° as per ASTM G76 standards. Say, if 5% glass fibers are present in catalyst material, then erosion resistance increases, but the density of glass fibers is very less because each glass fiber is approximately 20 microns in diameter and weight of individual is negligible. The composition in which 2% fiber is present has slightly higher erosion comparatively, but 3% glass fibers or more foreign inclusion like excessive binders can be eliminated that contributes much for the conversion of NOx. So 2% -3% glass fibers are preferred and optimized based on NOx conversion and erosion resistance property.

  6. True Tapping Mode Scanning Near-Field Optical Microscopy with Bent Glass Fiber Probes.

    Smirnov, A; Yasinskii, V M; Filimonenko, D S; Rostova, E; Dietler, G; Sekatskii, S K

    2018-01-01

    In scanning near-field optical microscopy, the most popular probes are made of sharpened glass fiber attached to a quartz tuning fork (TF) and exploiting the shear force-based feedback. The use of tapping mode feedback could be preferable. Such an approach can be realized, for example, using bent fiber probes. Detailed analysis of fiber vibration modes shows that realization of truly tapping mode of the probe dithering requires an extreme caution. In case of using the second resonance mode, probes vibrate mostly in shear force mode unless the bending radius is rather small (ca. 0.3 mm) and the probe's tip is short. Otherwise, the shear force character of the dithering persists. Probes having these characteristics were prepared by irradiation of a tapered etched glass fiber with a CW CO 2 laser. These probes were attached to the TF in double resonance conditions which enables achieving significant quality factor (4000-6000) of the TF + probe system (Cherkun et al., 2006). We also show that, to achieve a truly tapping character, dithering, short, and not exceeding 3 mm lengths of a freestanding part of bent fiber probe beam should also be used in the case of nonresonant excitation.

  7. True Tapping Mode Scanning Near-Field Optical Microscopy with Bent Glass Fiber Probes

    A. Smirnov

    2018-01-01

    Full Text Available In scanning near-field optical microscopy, the most popular probes are made of sharpened glass fiber attached to a quartz tuning fork (TF and exploiting the shear force-based feedback. The use of tapping mode feedback could be preferable. Such an approach can be realized, for example, using bent fiber probes. Detailed analysis of fiber vibration modes shows that realization of truly tapping mode of the probe dithering requires an extreme caution. In case of using the second resonance mode, probes vibrate mostly in shear force mode unless the bending radius is rather small (ca. 0.3 mm and the probe’s tip is short. Otherwise, the shear force character of the dithering persists. Probes having these characteristics were prepared by irradiation of a tapered etched glass fiber with a CW CO2 laser. These probes were attached to the TF in double resonance conditions which enables achieving significant quality factor (4000–6000 of the TF + probe system (Cherkun et al., 2006. We also show that, to achieve a truly tapping character, dithering, short, and not exceeding 3 mm lengths of a freestanding part of bent fiber probe beam should also be used in the case of nonresonant excitation.

  8. Error Measurements in an Acousto-Optic Tunable Filter Fiber Bragg Grating Sensor System

    1994-05-01

    for an ideal AOTF, at 833 and 838 nm using a TeO2 crystal ............................ 33 Figure 3.12. Frequency characteristics of Equation (3.43...multiple channels in an AOTF requires the presence of multiple RF frequencies to establish the complex grating. Since the crystal used in the AOTF ( TeO2 ) is...in germano- silicate glass . This index modulation, Bragg grating, acts as an optical band rejection filter for those wavelengths that meet the Bragg

  9. Thermal Effects on the Single-Mode Regime of Distributed Modal Filtering Rod Fiber

    Coscelli, Enrico; Poli, Federica; Alkeskjold, Thomas Tanggaard

    2012-01-01

    Power scaling of fiber laser systems requires the development of innovative active fibers, capable of providing high pump absorption, ultralarge effective area, high-order mode suppression, and resilience to thermal effects. Thermally induced refractive index change has been recently appointed...... as one major limitation to the achievable power, causing degradation of the modal properties and preventing to obtain stable diffraction-limited output beam. In this paper, the effects of thermally induced refractive index change on the guiding properties of a double-cladding distributed modal filtering...

  10. Dielectric studies of Graphene and Glass Fiber reinforced composites

    Praveen, D.; Shashi Kumar, M. E.; Pramod, R.

    2018-02-01

    Graphene and E-glass fibres are one of the key materials used currently due to their unique chemical and mechanical properties. Lately graphene has attracted many researchers across academic fraternity as it can yield better properties with lesser reinforcement percentages. The current research emphasizes on the development of graphene-based nanocomposites and its investigation on dielectric applications. The composites were fabricated by adding graphene reinforcements from 1%-3% by weight using conventional Hand-lay process. A thorough investigation was carried out to determine the dielectric behaviour of the nano-composites using impedance analyser according to ASTM standards. The dielectric measurements were carried out in the temperature range of 300K to 400K in a step of 20K. The current research proposes the material for application in capacitor industry as the sample of 2.5% weight fraction showed highest value of K with 14 at 26.1 Hz and 403K.

  11. Glass fiber sensors for detecting special nuclear materials at portal and monitor stations

    Hull, C.D.; Seymour, R.; Crawford, T.; Bliss, M.; Craig, R.A.

    2001-01-01

    Nuclear Safeguards and Security Systems LLC (NucSafe) participated in the Illicit Trafficking Radiation Assessment Program (ITRAP) recently conducted by the Austrian Research Center, Seibersdorf (ARCS) for IAEA, INTERPOL, and the World Customs Organization (IAEA, in press). This presentation reviews ITRAP test results of NucSafe instrumentation. NucSafe produces stationary, mobile, and hand-held systems that use neutron and gamma ray sensors to detect Special Nuclear Materials (SNM). Neutron sensors are comprised of scintillating glass fibers (trade name 'PUMA' for Pu Materials Analysis), which provide several advantages over 3 He and 10 BF 3 tubes. PUMA 6 Li glass fiber sensors offer greater neutron sensitivity and dynamic counting range with significantly less microphonic susceptibility than tubes, while eliminating transport and operational hazards. PUMA sensors also cost less per active area than gas tubes, which is important since rapid neutron detection at passenger, freight, and vehicle portals require large sensor areas to provide the required sensitivity

  12. Micropatterning of nanocomposite polymer scaffolds using sacrificial phosphate glass fibers for tendon tissue engineering applications.

    Alshomer, Feras; Chaves, Camilo; Serra, Tiziano; Ahmed, Ifty; Kalaskar, Deepak M

    2017-04-01

    This study presents a simple and reproducible method of micropatterning the novel nanocomposite polymer (POSS-PCU) using a sacrificial phosphate glass fiber template for tendon tissue engineering applications. The diameters of the patterned scaffolds produced were dependent on the diameter of the glass fibers (15 μm) used. Scaffolds were tested for their physical properties and reproducibility using various microscopy techniques. For the first time, we show that POSS-PCU supports growth of human tenocytes cells. Furthermore, we show that cellular alignment, their biological function and expression of various tendon related proteins such as scleraxis, collagen I and III, tenascin-C are significantly elevated on the micropatterned polymer surfaces compared to flat samples. This study demonstrated a simple, reproducible method of micropatterning POSS-PCU nanocomposite polymer for novel tendon repair applications, which when provided with physical cues could help mimic the microenvironment of tenocytes cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Fabrication of optical fiber of zinc tin borophosphate glass with zero photoelastic constant

    Saitoh, Akira; Oba, Yuya; Takebe, Hiromichi

    2015-10-01

    An optical fiber made of zinc tin boro-phosphate glass having a zero photoelastic constant, good water durability, and excluding hazardous elements was drawn from a prepared preform for use in a fiber-type current sensor device. The proposed cladding compositions enable single-mode propagation for a wavelength of 1550 nm, which is estimated from the difference in the refractive index between the core and cladding compositions. The drawing conditions should be controlled since the multiple-component glass is very sensitive to changes in viscosity and crystal precipitation during the heat-treated stretching of the preform. The temperature dependence of viscosity in the core and cladding reveals the feasibility of drawing.

  14. Dynamic compressive properties and failure mechanism of glass fiber reinforced silica hydrogel

    Yang Jie; Li Shukui; Yan Lili; Huo Dongmei; Wang Fuchi

    2010-01-01

    The dynamic compressive properties of glass fiber reinforced silica (GFRS) hydrogel were investigated using a spilt Hopkinson pressure bar. Failure mechanism of GFRS hydrogel was studied by scanning electron microscopy (SEM). Result showed that dynamic compressive stresses were much higher than the quasi-static compressive stresses at the same strain. The dynamic compressive strength was directly proportional to the strain rate with same sample dimensions. The dynamic compressive strength was directly proportional to the sample basal area at same strain rate. Dynamic compressive failure strain was small. At high strain rates, glass fibers broke down and separated from the matrix, pores shrank rapidly. Failure resulted from the increase of lateral tensile stress in hydrogel under dynamic compression.

  15. FeCoNi coated glass fibers in composite sheets for electromagnetic absorption and shielding behaviors

    Lee, Joonsik; Jung, Byung Mun; Lee, Sang Bok; Lee, Sang Kwan; Kim, Ki Hyeon

    2017-09-01

    To evaluate the electromagnetic (EM) absorption and shield of magnetic composite sheet, we prepared the FeCoNi coated glass fibers filled in composite sheet. The FeCoNi was coated by electroless plating on glass fiber as a filler. The coated FeCoNi found that consist of mixtures of bcc and fcc phase. The magnetization and coercivity of coated FeCoNi are about 110 emu/g and 57 Oe, respectively. The permittivity and permeability of the FeCoNi composite sheet were about 21 and 1, respectively. Power absorption increased 95% with the increment of frequency up to 10 GHz. Inter-decoupling of this composite sheet showed maximum 30 dB at around 5.3 GHz, which is comparable to that of a conductive Cu foil. Shielding effectiveness (SE) was measured by using rectangular waveguide method. SE of composite obtained about 37 dB at X-band frequency region.

  16. UV protection filters by dielectric multilayer thin films on Glass BK-7 and Infrasil 301

    Abdel-Aziz, M.M.; Azim, Osama A.; Abdel-Wahab, L.A.; Seddik, Mohamed M.

    2006-01-01

    The increasing use of Ultraviolet (UV) light in medicine, industrial environments, for cosmetic use, and even in consumer products necessitates that greater attention be paid to the potential hazards of this type of electromagnetic radiation. To avoid any adverse effects of exposure to this type of radiation, four suitable protection filters were produced to block three UV bands (UVA, UVB, and UVC). The design structure of the required dielectric multilayer filters was done by optical thin film technology using the absorbing property of UV radiation for the substrates and dielectric materials. The computer analyses of the multilayer filter formulas were prepared using Macleod Software for the production processes. The deposition technique was achieved on optical substrates (Glass BK-7 and Infrasil 301) by dielectric material combinations including Titanium dioxide (Ti 2 O 3 ), Hafnium dioxide (HfO 2 ), and Lima (mixture of oxides SiO 2 /Al 2 O 3 ); deposition being achieved using an electron beam gun. The output results of the theoretical and experimental transmittance values for spectral band from 200 nm to 800 nm were discussed in four processes. To analyze the suitability for use in 'real world' applications, the test pieces were subjected to the durability tests (adhesion, abrasion resistance, and humidity) according to Military Standard MIL-C-675C and MIL-C-48497A

  17. UV protection filters by dielectric multilayer thin films on Glass BK-7 and Infrasil 301

    Abdel-Aziz, M. M.; Azim, Osama A.; Abdel-Wahab, L. A.; Seddik, Mohamed M.

    2006-10-01

    The increasing use of Ultraviolet (UV) light in medicine, industrial environments, for cosmetic use, and even in consumer products necessitates that greater attention be paid to the potential hazards of this type of electromagnetic radiation. To avoid any adverse effects of exposure to this type of radiation, four suitable protection filters were produced to block three UV bands (UVA, UVB, and UVC). The design structure of the required dielectric multilayer filters was done by optical thin film technology using the absorbing property of UV radiation for the substrates and dielectric materials. The computer analyses of the multilayer filter formulas were prepared using Macleod Software for the production processes. The deposition technique was achieved on optical substrates (Glass BK-7 and Infrasil 301) by dielectric material combinations including Titanium dioxide (Ti 2O 3), Hafnium dioxide (HfO 2), and Lima (mixture of oxides SiO 2/Al 2O 3); deposition being achieved using an electron beam gun. The output results of the theoretical and experimental transmittance values for spectral band from 200 nm to 800 nm were discussed in four processes. To analyze the suitability for use in 'real world' applications, the test pieces were subjected to the durability tests (adhesion, abrasion resistance, and humidity) according to Military Standard MIL-C-675C and MIL-C-48497A.

  18. LABORATORY EVALUATION ON PERFORMANCE OF GLASS FIBER REINFORCED PLASTIC MORTAR PIPE CULVERTS

    Huawang Shi; Lianyu Wei

    2018-01-01

    This paper investigated the performance and behaviour of glass fiber reinforced plastic mortar (FRPM) pipes under different loading conditions. FRPM pipes with inner diameter of 1500 mm were prefabricated in factory. Mechanics performance testing (ring and axial compressive strength and elastic modulus), stiffness and fatigue test were carried out in laboratory. Ring stiffness test provided pipe stiffness (PS) which is a function of geometry and material type of pipe through parallel plate lo...

  19. Durability Characteristics Analysis of Plastic Worm Wheel with Glass Fiber Reinforced Polyamide

    Kim, Gun-Hee; Lee, Jeong-Won; Seo, Tae-Il

    2013-01-01

    Plastic worm wheel is widely used in the vehicle manufacturing field because it is favorable for weight lightening, vibration and noise reduction, as well as corrosion resistance. However, it is very difficult for general plastics to secure the mechanical properties that are required for vehicle gears. If the plastic resin is reinforced by glass fiber in the fabrication process of plastic worm wheel, it is possible to achieve the mechanical properties of metallic material levels. In this stud...

  20. Magneto-Optic Fiber Gratings Useful for Dynamic Dispersion Management and Tunable Comb Filtering

    Bao-Jian, Wu; Xin, Lu; Kun, Qiu

    2010-01-01

    Intelligent control of dispersion management and tunable comb filtering in optical network applications can be performed by using magneto-optic fiber Bragg gratings (MFBGs). When a nonuniform magnetic field is applied to the MFBG with a constant grating period, the resulting grating response is equivalent to that of a conventional chirped grating. Under a linearly nonuniform magnetic field along the grating, a linear dispersion is achieved in the grating bandgap and the maximal dispersion slope can come to 1260 ps/nm 2 for a 10-mm-long fiber grating at 1550 nm window. Similarly, a Gaussian-apodizing sampled MFBG is also useful for magnetically tunable comb filtering, with potential application to clock recovery from return-to-zero optical signals and optical carrier tracking. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  1. Fatigue resistance and stiffness of glass fiber-reinforced urethane dimethacrylate composite.

    Narva, Katja K; Lassila, Lippo V J; Vallittu, Pekka K

    2004-02-01

    Retentive properties of cast metal clasps decrease over time because of metal fatigue. Novel fiber-reinforced composite materials are purported to have increased fatigue resistance compared with metals and may offer a solution to the problem of metal fatigue. The aim of this study was to investigate the fatigue resistance and stiffness of E-glass fiber-reinforced composite. Twelve cylindrical fiber-reinforced composite test cylinders (2 mm in diameter and 60 mm in length) were made from light-polymerized urethane dimethacrylate monomer with unidirectional, single-stranded, polymer preimpregnated E-glass fiber reinforcement. Six cylinders were stored in dry conditions and 6 in distilled water for 30 days before testing. Fatigue resistance was measured by a constant-deflection fatigue test with 1 mm of deflection across a specimen span of 11 mm for a maximum of 150,000 loading cycles. The resistance of the cylinder against deflection was measured (N) and the mean values of the force were compared by 1-way analysis of variance (alpha = .05). The flexural modulus (GPa) was calculated for the dry and water-stored cylinders for the first loading cycle. Scanning electron microscopy was used to assess the distribution of the fibers, and the volume percent of fibers and polymer were assessed by combustion analysis. The test cylinders did not fracture due to fatigue following 150,000 loading cycles. Flexural modulus at the first loading cycle was 18.9 (+/- 2.9) GPa and 17.5 (+/- 1.7) GPa for the dry and water-stored cylinders, respectively. The mean force required to cause the first 1-mm deflection was 33.5 (+/- 5.2) N and 37.7 (+/- 3.6) N for the dry and water stored cylinders, respectively; however, the differences were not significant. After 150,000 cycles the mean force to cause 1-mm deflection was significantly reduced to 23.4 (+/- 8.5) N and 13.1 (+/- 3.5) N, respectively (P fiber- and polymer-rich areas within the specimens and indicated that individual fibers were

  2. Flexure and impact properties of glass fiber reinforced nylon 6-polypropylene composites

    Kusaseh, N. M.; Nuruzzaman, D. M.; Ismail, N. M.; Hamedon, Z.; Azhari, A.; Iqbal, A. K. M. A.

    2018-03-01

    In recent years, polymer composites are rapidly developing and replacing the metals or alloys in numerous engineering applications. These polymer composites are the topic of interests in industrial applications such as automotive and aerospace industries. In the present research study, glass fiber (GF) reinforced nylon 6 (PA6)-polypropylene (PP) composite specimens were prepared successfully using injection molding process. Test specimens of five different compositions such as, 70%PA6+30%PP, 65%PA6+30%PP+5%GF, 60%PA6+30%PP+10%GF, 55%PA6+30%PP+15%GF and 50%PA6+30%PP+20%GF were prepared. In the experiments, flexure and impact tests were carried out. The obtained results revealed that flexure and impact properties of the polymer composites were significantly influenced by the glass fiber content. Results showed that flexural strength is low for pure polymer blend and flexural strength of GF reinforced composite increases gradually with the increase in glass fiber content. Test results also revealed that the impact strength of 70%PA6+30%PP is the highest and 55%PA6+30%PP+15%GF composite shows moderate impact strength. On the other hand, 50%PA6+30%PP+20%GF composite shows low toughness or reduced impact strength.

  3. Low-loss tunable all-in-fiber filter for Raman spectroscopy

    Brunetti, Anna Chiara; Scolari, Lara; Lund-Hansen, Toke

    2011-01-01

    We show a novel in-line Rayleigh-rejection filter for Raman spectroscopy, based on a solid-core Photonic Crystal Fiber (PCF) filled with a high-index material. The device is low-loss and thermally tunable, and allows for a strong attenuation of the Rayleigh line at 532nm and the transmission...... of the Raman lines in a broad wavenumber range....

  4. Fracture strengths of chair-side-generated veneers cemented with glass fibers.

    Turkaslan, S; Bagis, B; Akan, E; Mutluay, M M; Vallittu, P K

    2015-01-01

    CAD/CAM (computer-aided design and computer-aided manufacturing) systems have refreshed the idea of chair-side production of restorations, but the fracture of ceramic veneers remains a problem. Cementation with glass fibers may improve the fracture strengths and affect the failure modes of CAD/CAM-generated ceramic veneers. Therefore, this study compared the fracture strengths of ceramic veneers produced at chair side and cemented with or without glass fibers with those of composite veneers. Thirty intact mandibular incisors were randomly divided into three groups ( n = 10) and treated with CAD/CAM-fabricated veneers cemented with dual-cure composite resin luting cement (CRLC; Group 1), CAD/CAM-fabricated veneers cemented with a glass fiber network (GFN) and dual-cure CRLC (Group 2), and a direct particulate filler composite veneer constructed utilizing fiber and a restorative composite resin (Group 3). The specimens were tested with a universal testing machine after thermal cycling treatment. The loads at the start of fracture were the lowest for traditionally fabricated composite veneers and higher for CAD/CAM-generated. Veneers cemented either without or with the GFN. The failure initiation loads (N) for the veneers were 798.92 for Group 1, 836.27 for Group 2, and 585.93 for Group 3. The predominant failure mode is adhesive failure between the laminates and teeth for Group 1, cohesive failure in the luting layer for Group 2, and cohesive laminate failure for Group 3, which showed chipping and small fractures. Ceramic material is a reliable alternative for veneer construction at chair side. Fibers at the cementation interface may improve the clinical longevity and provide higher fracture strength values.

  5. Exotic Optical Fibers and Glasses: Innovative Material Processing Opportunities in Earth's Orbit.

    Cozmuta, Ioana; Rasky, Daniel J

    2017-09-01

    Exotic optical fibers and glasses are the platform material for photonics applications, primarily due to their superior signal transmission (speed, low attenuation), with extending bandwidth deep into the infrared, exceeding that of silica fibers. Gravitational effects (convection sedimentation) have a direct impact on the phase diagram of these materials and influence melting properties, crystallization temperatures, and viscosity of the elemental mix during the manufacturing process. Such factors constitute limits to the yield, transmission quality, and strength and value of these fibers; they also constrain the range of applications. Manufacturing in a gravity-free environment such as the Earth's Orbit also helps with other aspects of the fabrication process (i.e., improved form factor of the manufacturing unit, sustainability). In this article, revolutionary developments in the field of photonics over the past decade merge with the paradigm shift in the privatization of government-owned capabilities supporting a more diverse infrastructure (parabolic, suborbital, orbital), reduced price, and increased frequency to access space and the microgravity environment. With the increased dependence on data (demand, bandwidth, efficiency), space and the microgravity environment provide opportunities for optimized performance of these exotic optical fibers and glasses underlying the development of enabling technologies to meet future data demand. Existing terrestrial markets (Internet, telecommunications, market transactions) and emerging space markets (on-orbit satellite servicing, space manufacturing, space resources, space communications, etc.) seem to converge, and this innovative material processing opportunity of exotic optical fibers and glasses might just be that "killer app": technologically competitive, economically viable, and with the ability to close the business case.

  6. Effect of surface treatment on mechanical properties of glass fiber/stainless steel wire mesh reinforced epoxy hybrid composites

    N, Karunagaran [S.K.P Engineering College, Tiruvannamalai (India); A, Rajadurai [Anna University, Chennai (India)

    2016-06-15

    This paper investigates the effect of surface treatment for glass fiber, stainless steel wire mesh on tensile, flexural, inter-laminar shear and impact properties of glass fiber/stainless steel wire mesh reinforced epoxy hybrid composites. The glass fiber fabric is surface treated either by 1 N solution of sulfuric acid or 1 N solution of sodium hydroxide. The stainless steel wire mesh is also surface treated by either electro dissolution or sand blasting. The hybrid composites are fabricated using epoxy resin reinforced with glass fiber and fine stainless steel wire mesh by hand lay-up technique at room temperature. The hybrid composite consisting of acid treated glass fiber and sand blasted stainless steel wire mesh exhibits a good combination of tensile, flexural, inter-laminar shear and impact behavior in comparison with the composites made without any surface treatment. The fine morphological modifications made on the surface of the glass fiber and stainless steel wire mesh enhances the bonding between the resin and reinforcement which inturn improved the tensile, flexural, inter-laminar shear and impact properties.

  7. Bismuth silicate glass: A new choice for 2 μm fiber lasers

    Ding, Jia; Zhao, Guoying; Tian, Ying; Chen, Wei; Hu, Lili

    2012-11-01

    We report on a new Yb3+/Tm3+/Ho3+ co-doped bismuth silicate glass: SiO2-Bi2O3-R2O (R = Li, Na, K) for 2 μm fiber lasers. Bi2O3 was introduced into alkali silicate glass to optimize 2 μm emission properties. Physical, chemical and spectroscopic properties of Yb3+/Tm3+/Ho3+ co-doped SiO2-Bi2O3-R2O (SBR) glass were presented. The Yb3+/Tm3+/Ho3+ co-doped SBR glass shows excellent thermal stability (ΔT = 162 °C), an intense 2.0 μm emission pumped by 980 nm LD with a lifetime of 1.33 ms and width of 168 nm, large maximum emission cross section of Ho3+ (5.3 × 10-21 cm2), thus large σemτ product (7.049 × 10-24 cm2 s), which suggest its application in 2 μm fiber lasers.

  8. Nanocellulose in spun continuous fibers: A review and future outlook

    Craig Clemons

    2016-01-01

    Continuous fibers are commonly manufactured for a wide variety of uses such as filters, textiles, and composites. For example, most fibrous reinforcements (e.g., carbon fiber, glass fiber) for advanced composites are continuous fibers or yarns, fabrics, and preforms made from them. This allows broad flexibility in design and manufacturing approaches by controlling...

  9. Grafting Carbon Nanotubes on Glass Fiber by Dip Coating Technique to Enhance Tensile and Interfacial Shear Strength

    Bahador Dastorian Jamnani

    2015-01-01

    Full Text Available The effects of noncovalent bonding and mechanical interlocking of carbon nanotubes (CNT coating on tensile and interfacial strength of glass fiber were investigated. CNT were coated over glass fiber by a simple dip coating method. Acid treated CNT were suspended in isopropanol solution containing Nafion as binding agent. To achieve uniform distribution of CNT over the glass fiber, an optimized dispersion process was developed by two parameters: CNT concentration and soaking time. CNT concentration was varied from 0.4 to 2 mg/mL and soaking time was varied from 1 to 180 min. The provided micrographs demonstrated appropriate coating of CNT on glass fiber by use of CNT-Nafion mixture. The effects of CNT concentration and soaking time on coating layer were studied by performing single fiber tensile test and pull-out test. The obtained results showed that the optimum CNT concentration and soaking time were 1 mg/mL and 60 min, respectively, which led to significant improvement of tensile strength and interfacial shear stress. It was found that, at other concentrations and soaking times, CNT agglomeration or acutely curly tubes appeared over the fiber surface which caused a reduction of nanotubes interaction on the glass fiber.

  10. Scintillating-Glass-Fiber neutron sensors, their application and performance for plutonium detection and monitoring

    Seymour, R.S.; Richardson, B.; Morichi, M.; Bliss, M.; Craig, R.A.; Sunberg, D.S.

    1998-01-01

    Most neutron detection sensors presently employ 3 He gas-filled detectors. Despite their excellent performance and widespread use, there are significant limitations to this technology. A significant alternative neutron sensor utilizing neutron-active material incorporated into a glass scintillator is presented that offers novel commercial sensors not possible or practical with gas tube technology. The scintillating optical fiber permits sensors with a multitude of sizes ranging from devices of a single fiber of 150μm to sensors with tens of thousands of fibers with areas as large as 5m 2 depending on the neutron flux to be measured. A second significant advantage is the use of high-speed electronics that allow a greater dynamic range, not possible with gas detectors. These sensors are flexible, conformable and less sensitive to vibration that optimizes the source-to-detector geometry and provides robust performance in field applications. The glass-fibers are sensitive to both gamma rays and neutrons. However the coincidence electronics are optimized for neutron to gamma ray discrimination allowing very sensitive measurements with a low false-alarm rate. Applications include SNM surveillance, material control and accountability (MC and A), safeguard inspections, Pu health physics / bioassay and environmental characterization. (author)

  11. "Brick-and-Mortar" Nanostructured Interphase for Glass-Fiber-Reinforced Polymer Composites.

    De Luca, Francois; Sernicola, Giorgio; Shaffer, Milo S P; Bismarck, Alexander

    2018-02-28

    The fiber-matrix interface plays a critical role in determining composite mechanical properties. While a strong interface tends to provide high strength, a weak interface enables extensive debonding, leading to a high degree of energy absorption. Balancing these conflicting requirements by engineering composite interfaces to improve strength and toughness simultaneously still remains a great challenge. Here, a nanostructured fiber coating was realized to manifest the critical characteristics of natural nacre, at a reduced length scale, consistent with the surface curvature of fibers. The new interphase contains a high proportion (∼90 wt %) of well-aligned inorganic platelets embedded in a polymer; the window of suitable platelet dimensions is very narrow, with an optimized platelet width and thickness of about 130 and 13 nm, respectively. An anisotropic, nanostructured coating was uniformly and conformally deposited onto a large number of 9 μm diameter glass fibers, simultaneously, using self-limiting layer-by-layer assembly (LbL); this parallel approach demonstrates a promising strategy to exploit LbL methods at scale. The resulting nanocomposite interphase, primarily loaded in shear, provides new mechanisms for stress dissipation and plastic deformation. The energy released by fiber breakage in tension appear to spread and dissipate within the nanostructured interphase, accompanied by stable fiber slippage, while the interfacial strength was improved up to 30%.

  12. Development of suspended core soft glass fibers for far-detuned parametric conversion

    Rampur, Anupamaa; Ciąćka, Piotr; Cimek, Jarosław; Kasztelanic, Rafał; Buczyński, Ryszard; Klimczak, Mariusz

    2018-04-01

    Light sources utilizing χ (2) parametric conversion combine high brightness with attractive operation wavelengths in the near and mid-infrared. In optical fibers, it is possible to use χ (3) degenerate four-wave mixing in order to obtain signal-to-idler frequency detuning of over 100 THz. We report on a test series of nonlinear soft glass suspended core fibers intended for parametric conversion of 1000-1100 nm signal wavelengths available from an array of mature lasers into the near-to-mid-infrared range of 2700-3500 nm under pumping with an erbium sub-picosecond laser system. The presented discussion includes modelling of the fiber properties, details of their physical development and characterization, and experimental tests of parametric conversion.

  13. Energy Conservation in Optical Fibers With Distributed Brick-Walls Filters

    Garcia, Javier; Ghozlan, Hassan; Kramer, Gerhard

    2018-05-01

    A band-pass filtering scheme is proposed to mitigate spectral broadening and channel coupling in the Nonlinear Schr\\"odinger (NLS) fiber optic channel. The scheme is modeled by modifying the NLS Equation to include an attenuation profile with multiple brick-wall filters centered at different frequencies. It is shown that this brick-walls profile conserves the total in-band energy of the launch signal. Furthermore, energy fluctuations between the filtered channels are characterized, and conditions on the channel spacings are derived that ensure energy conservation in each channel. The maximum spectral efficiency of such a system is derived, and a constructive rule for achieving it using Sidon sequences is provided.

  14. Voronoi polygons and self-consistent technique used to compute the airflow resistivity of randomly placed fibers in glass wool

    Tarnow, Viggo

    2002-01-01

    is constant, and equal to the constant current value. A computation of resistivity from fiber density and diameter will be presented for a model of glass wool that consists of parallel randomly placed fibers with equal diameters. The computation is based on Voronoi polygons, and the results will be compared...

  15. Transient radiation effects in D.O.I. optical materials: Schott filter glass

    Simmons-Potter, K.

    1998-07-01

    Department of Energy and Defense Programs systems are becoming increasingly reliant on the use of optical technologies that must perform under a range of ionizing radiation environments. In particular, the radiation response of materials under consideration for applications in direct optical initiation (D.O.I.) schemes must be well characterized. In this report, transient radiation effects observed in Schott filter glass S-7010 are characterized. Under gamma exposure with 2 MeV photons in a 20--30 nsec pulse, the authors observe strong initial induced fluorescence in the red region of the spectrum followed by significant induced absorption over the same spectral region. Peak induced absorption coefficients of 0.113 cm -1 and 0.088 cm -1 were calculated at 800 nm and 660 nm respectively

  16. A rapid and economic in-house DNA purification method using glass syringe filters.

    Yun-Cheol Kim

    Full Text Available BACKGROUND: Purity, yield, speed and cost are important considerations in plasmid purification, but it is difficult to achieve all of these at the same time. Currently, there are many protocols and kits for DNA purification, however none maximize all four considerations. METHODOLOGY/PRINCIPAL FINDINGS: We now describe a fast, efficient and economic in-house protocol for plasmid preparation using glass syringe filters. Plasmid yield and quality as determined by enzyme digestion and transfection efficiency were equivalent to the expensive commercial kits. Importantly, the time required for purification was much less than that required using a commercial kit. CONCLUSIONS/SIGNIFICANCE: This method provides DNA yield and quality similar to that obtained with commercial kits, but is more rapid and less costly.

  17. Study of the Effect of Reinforced Glass Fibers on Fatigue Properties for Composite Materials

    Mohamed G. Hamad

    2013-05-01

    Full Text Available This  research  included  the  study of  the effect  of  reinforced  glass fibers  on  fatigue  properties  for composite materials. Polyester  resin  is used  as  connective  material(matrix in two types  of  glass  fibers  for reinforced. The  first  type  is regular  glass fibers  (woven  roving with the  directional(0-90, the second  is  glass  fibers  with  the  random  direction. The first type is the panels with regular reinforced (0-90, and with number of layer (1,2.The  second  type  is  the  panels with random  reinforced  and  with  number  of  layers (1,2. The  results  and  the  laboratory  examinations  for  the samples  reinforce  with  fibers  have  manifested (0-90  that there  is  a decrease  in the number  of  cycles  to the  fatigue  limit  when  the  number  of  reinforce  layers  have  increased . And  an elasticity of this  type  of  samples  are decreased  by  increasing  the number  of  reinforced  layers  with  fiber  .We  find  the  random  reinforced  number  of  fatigue  cycles  for the samples  with  two  layers  of  random  reinforced  are  decreased  more  than the samples  with  one  layer of random  reinforced .

  18. The effects of embedded piezoelectric fiber composite sensors on the structural integrity of glass-fiber-epoxy composite laminate

    Konka, Hari P.; Wahab, M. A.; Lian, K.

    2012-01-01

    Piezoelectric fiber composite sensors (PFCSs) made from micro-sized lead zirconate titanate (PZT) fibers have many advantages over the traditional bulk PZT sensors for embedded sensor applications. PFCSs as embedded sensors will be an ideal choice to continuously monitor the stress/strain levels and health conditions of composite structures. PFCSs are highly flexible, easily embeddable, have high compatibility with composite structures, and also provides manufacturing flexibility. This research is focused on examining the effects of embedding PFCS sensors (macro-fiber composite (MFC) and piezoelectric fiber composite (PFC)) on the structural integrity of glass-fiber-epoxy composite laminates. The strengths of composite materials with embedded PFCSs and conventional PZT sensors were compared, and the advantages of PFCS sensors over PZTs were demonstrated. Initially a numerical simulation study is performed to understand the local stress/strain field near the embedded sensor region inside a composite specimen. High stress concentration regions were observed near the embedded sensor corner edge. Using PFCS leads to a reduction of 56% in longitudinal stress concentration and 38% in transverse stress concentration, when compared to using the conventional PZTs as embedded sensors. In-plane tensile, in-plane tension-tension fatigue, and short beam strength tests are performed to evaluate the strengths/behavior of the composite specimens containing embedded PFCS. From the tensile test it is observed that embedding PFCS and PZT sensors in the composite structures leads to a reduction in ultimate strength by 3 and 6% respectively. From the fatigue test results it is concluded that both embedded PFCS and PZT sensors do not have a significant effect on the fatigue behavior of the composite specimens. From the short beam strength test it is found that embedding PFCS and PZT sensors leads to a reduction in shear strength by 7 and 15% respectively. Overall the pure PZT sensors

  19. A glass fiber-reinforced composite - bioactive glass cranioplasty implant: A case study of an early development stage implant removed due to a late infection.

    Posti, Jussi P; Piitulainen, Jaakko M; Hupa, Leena; Fagerlund, Susanne; Frantzén, Janek; Aitasalo, Kalle M J; Vuorinen, Ville; Serlo, Willy; Syrjänen, Stina; Vallittu, Pekka K

    2015-03-01

    This case study describes the properties of an early development stage bioactive glass containing fiber-reinforced composite calvarial implant with histology that has been in function for two years and three months. The patient is a 33-year old woman with a history of substance abuse, who sustained a severe traumatic brain injury later unsuccessfully treated with an autologous bone flap and a custom-made porous polyethylene implant. She was thereafter treated with developmental stage glass fiber-reinforced composite - bioactive glass implant. After two years and three months, the implant was removed due to an implant site infection. The implant was analyzed histologically, mechanically, and in terms of chemistry and dissolution of bioactive glass. Mechanical integrity of the load bearing fiber-reinforced composite part of the implant was not affected by the in vivo period. Bioactive glass particles demonstrated surface layers of hydroxyapatite like mineral and dissolution, and related increase of pH was considerably less after two and three months period than that for fresh bioactive glass. There was a difference in the histology of the tissues inside the implant areas near to the margin of the implant that absorbed blood during implant installation surgery, showed fibrous tissue with blood vessels, osteoblasts, collagenous fibers with osteoid formation, and tiny clusters of more mature hard tissue. In the center of the implant, where there was less absorbed blood, only fibrous tissue was observed. This finding is in line with the combined positron emission tomography - computed tomography examination with (18F)-fluoride marker, which demonstrated activity of the mineralizing bone by osteoblasts especially at the area near to the margin of the implant 10 months after implantation. Based on these promising reactions found in the bioactive glass containing fiber-reinforced composite implant that has been implanted for two years and three months, calvarial

  20. Novel High Temperature and Radiation Resistant Infrared Glasses and Optical Fibers for Sensing in Advanced Small Modular Reactors

    Ballato, John [Clemson Univ., SC (United States)

    2018-01-22

    One binary and three series of ternary non-oxide pure sulfide glasses compositions were investigated with the goal of synthesizing new glasses that exhibit high glass transition (Tg) and crystallization (Tc) temperatures, infrared transparency, and reliable glass formability. The binary glass series consisted of Ges2 and La2S3 and the three glass series in the x(nBaS + mLa2S3) + (1-2x)GeS2 ternary system have BaS:La2S3 modifier ratios of 1:1, 1:2, and 2:1 with . With these glasses, new insights were realized as to how ionic glasses form and how glass modifiers affect both structure and glass formability. All synthesized compositions were characterized by Infrared (IR) and Raman spectroscopies and differential thermal analysis (DTA) to better understand the fundamental structure, optical, and thermal characteristics of the glasses. After a range of these glasses were synthesized, optimal compositions were formed into glass disks and subjected to gamma irradiation. Glass disks were characterized both before and after irradiation by microscope imaging, measuring the refractive index, density, and UV-VIS-IR transmission spectra. The final total dose the samples were subjected to was ~2.5 MGy. Ternary samples showed a less than 0.4% change in density and refractive index and minimal change in transmission window. The glasses also resisted cracking as seen in microscope images. Overall, many glass compositions were developed that possess operating temperatures above 500 °C, where conventional chalcogenide glasses such as As2S3 and have Tgs from ~200-300 °C, and these glasses have a greater than Tc – Tg values larger than 100 °C and this shows that these glasses have good thermal stability of Tg such that they can be fabricated into optical fibers and as such can be considered candidates for high temperature infrared fiber optics. Initial fiber fabrication efforts showed that selected glasses could be drawn but larger

  1. Relining effects on the push-out shear bond strength of glass fiber posts

    Adriana Rosado Valente ANDRIOLI

    Full Text Available Abstract Introduction The correct use of glass fiber posts in endodontically treated teeth is essential for the clinical success of restorative treatment. Objective This study evaluated the push-out shear bond strength of relined (R or non-relined (NR glass fiber posts, cemented with self-adhesive resin cement [RelyXTM U100 (U100] and conventional resin cement [RelyXTM ARC (ARC]. Material and method Sixty human single-rooted teeth were endodontically treated and divided into ARC-NR; U100-NR; ARC-R; U100-R groups. The teeth were sectioned into cervical, middle and apical thirds, and subjected to the push-out test. Bond strength was analyzed by the Friedman test; cement and post types were compared by the Mann Whitney test. The pattern of failures was evaluated with digital camera through images at 200x magnification, and was classified as adhesive (at the cement/dentin or cement/post interface, cohesive (cement or post, and mixed failures. Result In ARC-NR, bond strength values were higher in the cervical third; in U100-NR and ARC-R they were similar between the thirds. In U100-R, in the cervical and middle thirds the bond strength values were similar, and there was lower value in the apical third. For non-relined glass fiber posts, the highest mean bond strength values were observed with self-adhesive resin cement. Whereas, relined posts cemented with conventional resin cement had stronger cement layer in comparison with non-relined fiber posts. Conclusion The post relining technique was efficient in ARC-R. ARC-NR and U100-R showed improved bond strength in the cervical region of canal walls. The main failures were adhesive at the cement-post interface.

  2. Online Structural-Health Monitoring of Glass Fiber-Reinforced Thermoplastics Using Different Carbon Allotropes in the Interphase

    Michael Thomas Müller

    2018-06-01

    Full Text Available An electromechanical response behavior is realized by nanostructuring the glass fiber interphase with different highly electrically conductive carbon allotropes like carbon nanotubes (CNT, graphene nanoplatelets (GNP, or conductive carbon black (CB. The operational capability of these multifunctional glass fibers for an online structural-health monitoring is demonstrated in endless glass fiber-reinforced polypropylene. The electromechanical response behavior, during a static or dynamic three-point bending test of various carbon modifications, shows qualitative differences in the signal quality and sensitivity due to the different aspect ratios of the nanoparticles and the associated electrically conductive network densities in the interphase. Depending on the embedding position within the glass fiber-reinforced composite compression, shear and tension loadings of the fibers can be distinguished by different characteristics of the corresponding electrical signal. The occurrence of irreversible signal changes during the dynamic loading can be attributed to filler reorientation processes caused by polymer creeping or by destruction of electrically conductive paths by cracks in the glass fiber interphase.

  3. High modulus rare earth and beryllium containing silicate glass compositions. [for glass reinforcing fibers

    Bacon, J. F. (Inventor)

    1976-01-01

    Glass compositions having a Young's modulus of at least 16 million psi and a specific modulus of at least 110 million inches consisting essentially of approximately, by weight, 20 to 43% SiO2, 8 to 21% Al2O3, 4 to 10% BeO, 27 to 58% of at least one oxide selected from a first group consisting of Y2O3, La2O3, Nd2O3, Ce2O3, Ce2O3, and the mixed rare earth oxides, and 3 to 12% of at least one oxide selected from a second group consisting of MgO, ZrO2, ZnO and CaO are described. The molar ratio of BeO to the total content of the first group oxides is from 1.0 to 3.0.

  4. In vitro stimulation of vascular endothelial growth factor by borate-based glass fibers under dynamic flow conditions.

    Chen, Sisi; Yang, Qingbo; Brow, Richard K; Liu, Kun; Brow, Katherine A; Ma, Yinfa; Shi, Honglan

    2017-04-01

    Bioactive borate glass has been recognized to have both hard and soft tissue repair and regeneration capabilities through stimulating both osteogenesis and angiogenesis. However, the underlying biochemical and cellular mechanisms remain unclear. In this study, dynamic flow culturing modules were designed to simulate the micro-environment near the vascular depletion and hyperplasia area in wound-healing regions, thus to better investigate the mechanisms underlying the biocompatibility and functionality of borate-based glass materials. Glass fibers were dosed either upstream or in contact with the pre-seeded cells in the dynamic flow module. Two types of borate glasses, doped with (1605) or without (13-93B3) CuO and ZnO, were studied along with the silicate-based glass, 45S5. Substantial fiber dissolution in cell culture medium was observed, leading to the release of ions (boron, sodium and potassium) and the deposition of a calcium phosphate phase. Different levels of vascular endothelial growth factor secretion were observed from cells exposed to these three glass fibers, and the copper/zinc containing borate 1605 fibers exhibited the most positive influence. These results indicate that dynamic studies of in vitro bioactivity provide useful information to understand the in vivo response to bioactive borate glasses. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Microstructural evaluation and flexural mechanical behavior of pultruded glass fiber composites

    Chacon, Y.G.; Paciornik, S.; D'Almeida, J.R.M.

    2010-01-01

    Research highlights: → Mosaic images fully characterize the microstructure of heterogeneous materials. → Mosaic images have advantages over microscopy techniques using single fields. → UV and water immersion aging are minimized at the fibers' direction. → UV radiation produced marked changes on the composite surface. - Abstract: The microstructure of a pultruded glass fiber-reinforced composite was fully characterized using digital image analysis. A mosaic technique was used to analyze the entire thickness along specimens' cross-sections, enabling the visualization of the fiber, resin and filler spatial distribution. The advantages of this technique over the usual analysis on single fields, is presented and discussed. The fiber spatial distribution was correlated with flexural mechanical properties as a function of the specimens' position along the length and across the cross section of the composite. The influence of aging by immersion in distilled water and by UV radiation on flexural properties was also analyzed. Minor variation due to aging occurred when longitudinal specimens were tested. Transversally to the fibers, the matrix-dominated composite properties were more affected.

  6. Osteoconductive properties of two different bioactive glass forms (powder and fiber) combined with collagen

    Magri, Angela Maria Paiva; Fernandes, Kelly Rossetti; Ueno, Fabio Roberto; Kido, Hueliton Wilian; da Silva, Antonio Carlos; Braga, Francisco José Correa; Granito, Renata Neves; Gabbai-Armelin, Paulo Roberto; Rennó, Ana Claudia Muniz

    2017-11-01

    Bioactive Glasses (BG) is a group of synthetic silica-based materials with the unique ability to bond to living bone and can be used in bone repair. Although the osteogenic potential of BG, this material may have not present sufficient osteoconductive and osteoinductive properties to allow bone regeneration, especially in compromised situations. In order to overcome this limitation, it was proposed the combination the BG in two forms (powder and fiber) combined with collagen type I (COL-1). The aim of this study was to evaluate the BG/COL-based materials in terms of morphological characteristics, physicochemical features and mineralization. Additionally, the second objective was to investigate and compare the osteoconductive properties of two different bioactive glass forms (powder and fiber) enriched or not with collagen using a tibial bone defect model in rats. For this, four different formulations (BG powder - BGp, BG powder enriched with collagen - BGp/Col, BG fibers - BGf and BGp fibers enriched with collagen - BGf/Col) were developed. The physicochemical and morphological modifications were analyzed by SEM, FTIR, calcium assay and pH measurement. For in vivo evaluations, histopathology, morphometrical and immunohistochemistry were performed in a tibial defect in rats. The FTIR analysis indicated that BGp and BGf maintained the characteristic peaks for this class of material. Furthermore, the calcium assay showed an increased Ca uptake in the BG fibers. The pH measurements revealed that BGp (with or without collagen) presented higher pH values compared to BGf. In addition, the histological analysis demonstrated no inflammation for all groups at the site of the injury, besides a faster material degradation and higher bone ingrowth for groups with collagen. The immunohistochemistry analysis demonstrated Runx-2 and Rank-L expression for all the groups. Those findings support that BGp with collagen can be a promising alternative for treating fracture of difficult

  7. Optimized process for recovery of glass- and carbon fibers with retained mechanical properties by means of near- and supercritical fluids

    Sokoli, Hülya U.; Beauson, Justine; Simonsen, Morten E.

    2017-01-01

    on the resin degradation efficiency and the quality of the recovered glass and carbon fibers. Supercritical acetone at 260 ºC, 60 bar and a c/s ratio up to 2.1 g/mL could achieve nearly complete degradation of the resin. The glass fibers were recovered with up to 89% retained tensile strength compared...... to the virgin glass fibers. The use of near-critical water reduced the tensile strength of the glass fibers by up to 65%, whereas the carbon fibers were recovered with retained tensile strength compared to the virgin carbon fibers using water or acetone.......Degradation of hybrid fiber composites using near-critical water or supercritical acetone has been investigated in this study. Process parameters such as temperature (T= 260-300 ºC), pressure (p = 60-300 bar) and composite/solvent (c/s = 0.29-2.1 g/mL) ratio were varied to determine the effect...

  8. Intra-Laminar Fracture Toughness of Glass Fiber Reinforced Polymer By Using Theory, Experimentation and FEA

    Firojkhan, Pathan; Tanpure, Kshitijit; Dawale, Ajinkya; Patil, Shital

    2018-04-01

    Fiber reinforced polymer (FRP) composites are widely use in aerospace, marine, auto-mobile and civil engineering applications because of their high strength-to-weight and stiffness-to-weight ratios, corrosion resistance and potentially high durability. The purpose of this research is to experimentally investigate the mechanical and fracture properties of glass-fiber reinforced polyester composite material, 450 g/m 2 randomly distributed glass-fiber mat also known as woven strand mat with polyester resin as a matrix. The samples have been produced by the conventional hand layup process and the specimens were prepared as per the ASTM standards. The tensile test was performed on the composite specimens using Universal testing machine (UTM) which are used for the finite element simulation of composite Layered fracture model. The mechanical properties were evaluated from the stress vs. strain curve obtained from the test result. Later, fracture tests were performed on the CT specimen. In case of CT specimen the load vs. Displacement plot obtained from the experimental results was used to determine the fracture properties of the composite. The failure load of CT specimen using FEA is simulated which gives the Stress intensity factor by using FEA. Good agreement between the FEA and experimental results was observed.

  9. 2.45 GHz Microwave Processing and Its Influence on Glass Fiber Reinforced Plastics

    Zaremba, Swen

    2018-01-01

    During the production of fiber-reinforced composite materials, liquid resin is introduced into the fiber material and cured, i.e., hardened. An elevated temperature is needed for this curing. Microwave curing of composites has been investigated for some time, but it has mostly been done using small domestic or laboratory equipment. However, no investigation has been carried out using an industrial-sized chamber-microwave for glass fiber-reinforced plastic (GFRP). Here, we show that microwave curing produces laminates of the same quality as oven-cured ones. The study shows that, if the process is done right, GFRP samples can be produced with an industrial scale microwave. Even if not fully cured, microwave samples show a glass transition temperature measured with DMA (Tg-DMA) that is comparable to the Tg-DMA according to the proposed cure cycle on the data sheet. Specific microwave-cured configurations show better inter-laminar shear strength than oven specimens. The results show that microwave-based heat introduction can be a beneficial curing method for GFRP laminates. A microwave-optimized process is faster and leads to better mechanical properties. PMID:29783684

  10. A single-frequency, ring cavity Tm-doped fiber laser based on a CMFBG filter

    Li, Qi; Yan, Fengping; Peng, Wanjing; Liu, Shuo; Feng, Ting; Tan, Siyu; Liu, Peng

    2013-01-01

    A single-frequency (SF), continuous-wave (CW), ring cavity Tm-doped fiber laser has been proposed and demonstrated. A chirped moiré fiber grating (CMFBG) was used as an ultra-narrow filter in the laser cavity to ensure SF operation. When the launched pump power was fixed at 2 W, this proposed laser was in stable operation with a central wavelength, optical signal-to-noise ratio, and full width at half maximum of 1942.8140 nm, 47 dB, and 0.0522 nm, respectively, with a resolution of 0.05 nm. The maximum output power of this laser is 95 mW, a higher output power is restricted by the optical circulator that is used in the cavity. The SF operation of this laser was confirmed by the self-homodyne method. To the best of the authors’ knowledge, this is the first report on an SF, CW, ring cavity Tm-doped fiber laser with a CMFBG filter. (letter)

  11. Behaviour of reinforced columns with E_Glass fiber and carbon fiber

    BOUCHELAGHEM Hafida; BEZAZI Abederrezak; Benzanache Naziha; SCARPA Fabrizio

    2018-01-01

    Externally bonded reinforcement using Fiber Reinforced Polymer (FRP) is a good response to the concern represented by the need for rehabilitation of concrete structures. These techniques are more and more attractive because of their fast and low labour costs, very good strength to weight ratio, good fatigue properties, and non-corrosive characteristics of FRP. The present work is an experimental study investigating the mechanical behaviour under a uni-axial loading of short concrete columns r...

  12. Degradation of glass-fiber reinforced plastics by low temperature irradiation

    Nishijima, S.; Nishiura, T.; Ueno, S.; Tsukazaki, Y.; Okada, T.; Okada, T.M.; Miyata, K.; Kodaka, H.

    1998-01-01

    Low-temperature irradiation effects of glass-fiber reinforced plastics (GFRP) have been investigated in terms of mechanical properties such as interlaminar shear strength and creep, in order to obtain the selection standard of insulating materials of superconducting magnets used for fusion reactor. It was revealed that the degradation of interlaminar shear strength was strongly dependent of characteristics of matrix and/or glass/epoxy interface. Especially, the research has been carried out towards the creep behaviour of epoxy which is the matrix of GFRP, by both experimental and simulation method. It was suggested that the synergistic effects was observed in creep test. From the molecular dynamics simulation it was found that the cage effects was the one of the main reason of the stress effects of creep behavior under irradiation. (author)

  13. Effect of the impact directions, of the fibers and of the aging on the glass fibers composite resistance

    Vina, J.; Arguelles, A.; Zenasni, R.; Ouinas, D.

    2006-01-01

    Usually, composites of epoxy matrix reinforced with glass fiber are used in the fabrication of wind turbine blades. This material has an anisotropic structure and its mechanical properties are not the same in all the directions. The impact strength was evaluated from the mechanical tests carried out in two perpendicular directions. The effect of aging was analyzed immersing the specimens into water to 70 C, during different periods of time. From the results of the tests, the dynamic fracture toughness (Kid) and the resilience (KCV) were obtained. An important difference was obtained between the specimens taken out in the blade direction and in the perpendicular direction. The aging specimens, in the two directions, have showed continuous decrements in the dynamic toughness and resilience, from the first period of immersion of 15 days until 180 days. (authors)

  14. Gas chromatographic sensing on an optical fiber by mode-filtered light detection.

    Bruckner, C A; Synovec, R E

    1996-06-01

    A chemical sensor for gas phase measurements is reported which combines the principles of chemical separation and fiber optic detection. The analyzer incorporates an annular column Chromatographic sensor, constructed by inserting a polymer-clad optical fiber into a silica capillary. Light from a helium-neon laser is launched down the fiber, producing a steady intensity distribution within the fiber, but a low background of scattered light. When sample vapor is introduced to the sensor, and an analyte-rich volume interacts with the polymer cladding, Chromatographic retention is observed simultaneously with a change in the local refractive index of the cladding. An increase in cladding refractive index (RI) causes light to be coupled out of the fiber, with detection at a right-angle to the annular column length to provide optimum S/N ratio. This detection mechanism is called mode-filtered light detection. We report a gas Chromatographic separation on a 3.1 m annular column (320 microm i.d. silica tube, 228 microm o.d. fiber with a 12 microm fluorinated silicone clad) of methane, benzene, butanone and chlorobenzene in 6 min. The annular column length was reduced to 22 cm to function as a sensor, with selected organic vapors exhibiting unique retention times and detection selectivity. The detection selectivity is determined by the analyte RI and the partition coefficient into the cladding. The calculated limit of detection (LOD) for benzene vapor is 0.03% by volume in nitrogen, and several chlorinated species had LOD values less than 1%. For binary mixtures of organic vapors, the detected response appears to be the linear combination of the two organic standards, suggesting that the annular column may be useful as a general approach for designing chemical sensors that incorporate separation and optical detection principles simultaneously.

  15. The influence of glass fibers on the morphology of β-nucleated isotactic polypropylene evaluated by differential scanning calorimetry

    Janevski Aco

    2015-01-01

    Full Text Available The presence of fillers/fibers can significantly affect the polymorphic behavior of semi-crystalline polymers. The influence of glass fibers on morphology of β-nucleated iPP during isothermal and nonisothermal crystallization was analyzed in detail by DSC, and the kinetics and thermodynamic parameters were determined for the systems containing 10-60 % glass fibers. The presence of glass fibers in model composites with β-iPP has insignificant effect on the morphology of the polymer. Thermodynamic and kinetics parameters of crystallization of iPP in model composites are close to those obtained for the nucleated polymer. The relative content of β-crystalline phase is slightly affected by increasing glass fiber’s content from 10 % mas to 60 % mas, due to appearance of α-crystallites. However, the stability of β-crystalline phase is decreased by the increasing glass fibers content and there appeared certain amount of β1 and β2 phases which are known as disposed to recrystallization.

  16. Fiber sensor on the basis of Ge26As17Se25Te32 glass for FEWS analysis

    Velmuzhov, A. P.; Shiryaev, V. S.; Sukhanov, M. V.; Kotereva, T. V.; Churbanov, M. F.; Zernova, N. S.; Plekhovich, A. D.

    2018-01-01

    The high-purity Ge26As17Se25Te32 glass sample was prepared by chemical distillation purification method. This glass is characterized by high value of glass transition temperature (263°С), high optical transparency in the spectral range of 2-10 μm, and low content of residual impurities. The Ge26As17Se25Te32 glass rods were drawn into single-index fibers using the "rod" method and the single crucible technique. The optical losses in the 400 μm diameter fiber, fabricated by the "rod" method, were within 0.3-1 dB/m in the spectral range 5.2-9.3 μm. The minimum optical losses in the 320 μm diameter fiber, fabricated by the "crucible" technique, were 1.6-1.7 dB/m in the spectral range 6-8.5 μm. Using these Ge26As17Se25Te32 glass fibers as a sensor, the aqueous solutions of acetone (0-20 mol.%) and ethanol (0-90 mol.%) were analyzed by fiber evanescent wave spectroscopy. Peculiarities in the change of the integrated intensity and spectral position of absorption bands of these organic substances in dependence on the analyte composition and the length of the sensitive zone were established.

  17. Replacement of glass particles by multidirectional short glass fibers in experimental composites: Effects on degree of conversion, mechanical properties and polymerization shrinkage.

    Bocalon, Anne C E; Mita, Daniela; Narumyia, Isabela; Shouha, Paul; Xavier, Tathy A; Braga, Roberto Ruggiero

    2016-09-01

    To test the null hypothesis that the replacement of a small fraction of glass particles with random short glass fibers does not affect degree of conversion (DC), flexural strength (FS), fracture toughness (FT) and post-gel polymerization shrinkage (PS) of experimental composites. Four experimental photocurable composites containing 1 BisGMA:1 TEGDMA (by weight) and 60vol% of fillers were prepared. The reinforcing phase was constituted by barium glass particles (2μm) and 0%, 2.5%, 5.0% or 7.5% of silanated glass fibers (1.4mm in length, 7-13μm in diameter). DC (n=4) was obtained using near-FTIR. FS (n=10) was calculated via biaxial flexural test and FT (n=10) used the "single edge notched beam" method. PS at 5min (n=8) was determined using the strain gage method. Data were analyzed by ANOVA/Tukey test (DC, FS, PS) or Kruskal-Wallis/Dunn's test (FT, alpha: 5% for both tests). DC was similar among groups (p>0.05). Only the composite containing 5.0% of fibers presented lower FS than the control (pglass fibers significantly increased fracture toughness and reduced post-gel shrinkage of experimental composites. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  18. Quick analytical separation of glucose and fructose with impregnated woven glass fiber

    Jones, S.C.

    1978-01-01

    (1) A wide separation of glucose and fructose was obtained in 30 min with simple, inexpensive equipment using polysilicic impregnated woven glass fiber and the solvent acetone-n-butanol-1 M H 3 BO 3 (50:40:10). (2) A calibration of a radiochromatogram scanner was performed for 11 C. (3) Three Rsub(F) values could be compared to provide positive chemical identification of [ 11 C]glucose and [ 11 C]fructose. (4) Radiochemical composition and approximate specific activity were determined from a small aliquot (1-4 μl). (Auth.)

  19. Determination of mechanical properties of some glass fiber reinforced plastics suitable to Wind Turbine Blade construction

    Steigmann, R.; Savin, A.; Goanta, V.; Barsanescu, P. D.; Leitoiu, B.; Iftimie, N.; Stanciu, M. D.; Curtu, I.

    2016-08-01

    The control of wind turbine's components is very rigorous, while the tower and gearbox have more possibility for revision and repairing, the rotor blades, once they are deteriorated, the defects can rapidly propagate, producing failure, and the damages can affect large regions around the wind turbine. This paper presents the test results, performed on glass fiber reinforced plastics (GFRP) suitable to construction of wind turbine blades (WTB). The Young modulus, shear modulus, Poisson's ratio, ultimate stress have been determined using tensile and shear tests. Using Dynamical Mechanical Analysis (DMA), the activation energy for transitions that appear in polyester matrix as well as the complex elastic modulus can be determined, function of temperature.

  20. Paper-based microfluidics with high resolution, cut on a glass fiber membrane for bioassays.

    Fang, Xueen; Wei, Shasha; Kong, Jilie

    2014-03-07

    In this report, we describe a simple, low-cost, straight forward and highly reproducible fabrication method of microfluidic systems. This system was cut on a glass fiber membrane by a common cutter without using any other sophisticated equipment or organic solvents. This format represents a novel type of paper-based microfluidics with high resolution of the microchannel down to ~137 μm, comparable to those made by conventional photolithography. We successfully applied this method to microfluidics to create a star micro-array format of multiplexed urine tests in this study.

  1. Joining of aluminum sheet and glass fiber reinforced polymer using extruded pins

    Conte, Romina; Buhl, Johannes; Ambrogio, Giuseppina; Bambach, Markus

    2018-05-01

    The present contribution proposes a new approach for joining sheet metal and fiber reinforced composites. The joining process draws upon a Friction Stir Forming (FSF) process, which is performed on the metal sheet to produce slender pins. These pins are used to pierce through the composite. Joining is complete by forming a locking head out of the part if the pin sticks out of the composite. Pins of different diameters and lengths were produced from EN AW-1050 material, which were joined to glass fiber reinforced polyamide-6. The strength of the joint has been experimentally tested in order to understand the effect of the process temperature on the pins strength and therefore on the joining. The results demonstrate the feasibility of this new technique, which uses no excess material.

  2. Wavelength interrogation of fiber Bragg grating sensors based on crossed optical Gaussian filters.

    Cheng, Rui; Xia, Li; Zhou, Jiaao; Liu, Deming

    2015-04-15

    Conventional intensity-modulated measurements require to be operated in linear range of filter or interferometric response to ensure a linear detection. Here, we present a wavelength interrogation system for fiber Bragg grating sensors where the linear transition is achieved with crossed Gaussian transmissions. This unique filtering characteristic makes the responses of the two branch detections follow Gaussian functions with the same parameters except for a delay. The substraction of these two delayed Gaussian responses (in dB) ultimately leads to a linear behavior, which is exploited for the sensor wavelength determination. Beside its flexibility and inherently power insensitivity, the proposal also shows a potential of a much wider operational range. Interrogation of a strain-tuned grating was accomplished, with a wide sensitivity tuning range from 2.56 to 8.7 dB/nm achieved.

  3. Frequency and deflection analysis of cenosphere/glass fiber interply hybrid composite cantilever beam

    Bharath, J.; Joladarashi, Sharnappa; Biradar, Srikumar; Kumar, P. Naveen

    2018-04-01

    Interply hybrid laminates contain plies made of two or more different composite systems. Hybrid composites have unique features that can be used to meet specified design requirements in a more cost-effective way than nonhybrid composites. They offer many advantages over conventional composites including balanced strength and stiffness, enhanced bending and membrane mechanical properties, balanced thermal distortion stability, improved fatigue/impact resistance, improved fracture toughness and crack arresting properties, reduced weight and cost. In this paper an interply hybrid laminate composite containing Cenosphere reinforced polymer composite core and glass fiber reinforced polymer composite skin is analysied and effect of volume fraction of filler on frequency and load v/s deflection of hybrid composite are studied. Cenosphere reinforced polymer composite has increased specific strength, specific stiffness, specific density, savings in cost and weight. Glass fiber reinforced polymer composite has higher torsional rigidity when compared to metals. These laminate composites are fabricated to meet several structural applications and hence there is a need to study their vibration and deflection properties. Experimental investigation starts with fabrication of interply hybrid composite with cores of cenosphere reinforced epoxy composite volume fractions of CE 15, CE 25, CE15_UC as per ASTM E756-05C, and glasss fiber reinforced epoxy skin, cast product of required dimension by selecting glass fibre of proper thickness which is currently 0.25mm E-glass bidirectional woven glass fabric having density 2500kg/m3, in standard from cast parts of size 230mmX230mmX5mm in an Aluminum mould. Modal analysis of cantilever beam is performed to study the variation of natural frequency with strain gauge and the commercially available Lab-VIEW software and deflection in each of the cases by optical Laser Displacement Measurement Sensor to perform Load versus Deflection Analysis

  4. Long fiber Bragg grating sensor interrogation using discrete-time microwave photonic filtering techniques.

    Ricchiuti, Amelia Lavinia; Barrera, David; Sales, Salvador; Thevenaz, Luc; Capmany, José

    2013-11-18

    A novel technique for interrogating photonic sensors based on long fiber Bragg gratings (FBGs) is presented and experimentally demonstrated, dedicated to detect the presence and the precise location of several spot events. The principle of operation is based on a technique used to analyze microwave photonics (MWP) filters. The long FBGs are used as quasi-distributed sensors. Several hot-spots can be detected along the FBG with a spatial accuracy under 0.5 mm using a modulator and a photo-detector (PD) with a modest bandwidth of less than 1 GHz. The proposed interrogation system is intrinsically robust against environmental changes.

  5. Optical single sideband modulation radio over fiber system by using a fiber-Bragg-grating-based acousto-optic filter

    Gao, Song; Pei, Li; Li, Zhuoxuan; Liu, Chao; Wang, Yiqun; Weng, Sijun

    2013-03-01

    An optical single sideband (OSSB) modulation radio over a fiber system, by using an acousto-optic filter (AOF), is proposed and demonstrated. In the AOF, a uniform fiber Bragg grating is etched and modulated by an axially propagating acoustic wave. Due to the acousto-optic superlattice modulation, two secondary reflection peaks, centered on the primary reflection peak, are generated. In the scheme, an optical double-sideband signal passes though the AOF to realize OSSB modulation. Because the reflect depth of the primary peak is much deeper than those of the secondary peaks, the carrier experiences higher attenuation than the upper sideband, which means the carrier-to-sideband ratio (CSR) can be optimized at the same time. We demonstrate this scheme via simulations, and successfully reduce the CSR from 9.73 to 2.9 dB. As a result, the receiving sensitivity improved from -23.43 to -31.18 dBm at BER of 10-9 with 30 km long SMF.

  6. Optimization for Tribological Properties of Glass Fiber-Reinforced PTFE Composites with Grey Relational Analysis

    Firojkhan Pathan

    2016-01-01

    Full Text Available Most recent history shows that polytetrafluoroethylene (PTFE is widely used as antifrictional materials in industry for wide speed range. A high antifriction property of PTFE makes it suitable for dry friction bearing. Main disadvantage of using PTFE is its high wear rate, so extensive research had been carried out to improve the wear resistance with addition of filler material. This study focuses on four input parameters load, sliding speed, sliding distance, and percentage of glass fiber as a filler material. Taguchi method was used for experimentation; each parameter is having 3 levels with L27 orthogonal array. Grey relational analysis is used to convert multiple response parameters, namely, wear and coefficient of friction, into single grey relation grade. The optimal input parameters were selected based on the S/N ratio. It was observed that load 3 kg, sliding speed 5.1836 m/s (900 rpm, sliding distance 2 km, and 15% of glass fiber are optimal input parameters for PTFE without significantly affecting the wear rate and coefficient of friction.

  7. Thermal performance of glass fiber reinforced intumescent fire retardant coating for structural applications

    Ahmad, Faiz, E-mail: faizahmad@petronas.com.my; Ullah, Sami; Aziz, Hammad, E-mail: engr.hammad.aziz03@gmail.com; Omar, Nor Sharifah [Department of Mechanical Engineering, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Tronoh 31750 Perak (Malaysia)

    2015-07-22

    The results of influence of glass fiber addition into the basic intumescent coating formulation towards the enhancement of its thermal insulation properties are presented. The intumescent coatings were formulated from expandable graphite, ammonium polyphosphate, melamine, boric acid, bisphenol A epoxy resin BE-188, polyamide amine H-2310 hardener and fiberglass (FG) of length 3.0 mm. Eight intumescent formulations were developed and the samples were tested for their fire performance by burning them at 450°C, 650°C and 850°C in the furnace for two hours. The effects of each fire test at different temperatures; low and high temperature were evaluated. Scanning Electron Microscope, X-Ray Diffraction technique and Thermo Gravimetric Analysis were conducted on the samples to study the morphology, the chemical components of char and the residual weight of the coatings. The formulation, FG08 containing 7.0 wt% glass fiber provided better results with enhanced thermal insulation properties of the coatings.

  8. Multifunctional glass fiber/polyamide composites with thermal energy storage/release capability

    G. Fredi

    2018-04-01

    Full Text Available Thermoplastic composite laminates with thermal energy storage (TES capability were prepared by combining a glass fabric, a polyamide 12 (PA12 matrix and two different phase change materials (PCMs, i.e. a paraffinic wax microencapsulated in melamine-formaldehyde shells and a paraffin shape stabilized with carbon nanotubes. The melt flow index of the PA12/PCM blends decreased with the PCM concentration, especially in the systems with shape stabilized wax. Differential scanning calorimetry showed that, for the matrices with microcapsules, the values of enthalpy were approximately the 70% of the theoretical values, which was attributed to the fracture of some microcapsules. Nevertheless, most of the energy storage capability was preserved. On the other hand, much lower relative enthalpy values were measured on the composites with shape stabilized wax, due to a considerable paraffin leakage or degradation. The subsequent characterization of the glass fabric laminates highlighted that the fiber and void volume fractions were comparable for all the laminates except for that with the higher amount of shape stabilized wax, where the high viscosity of the matrix led to a low fiber volume fraction and higher void content. The mechanical properties of the laminates were only slightly impaired by PCM addition, while a more sensible drop of the elastic modulus, of the stress at break and of the interlaminar shear strength could be observed in the shape stabilized wax systems.

  9. Quantification of defects depth in glass fiber reinforced plastic plate by infrared lock-in thermography

    Ranjit, Shrestha; Kim, Won Tae [Kongju National University, Cheonan (Korea, Republic of); Choi, Man Yong [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of)

    2016-03-15

    The increasing use of composite materials in various industries has evidenced the need for development of more effective nondestructive evaluation methodologies in order to reduce rejected parts and to optimize production cost. Infrared thermography is a noncontact, fast and reliable non-destructive evaluation technique that has received vast and growing attention for diagnostic and monitoring in the recent years. This paper describes the quantitative analysis of artificial defects in Glass fiber reinforced plastic plate by using Lockin infrared thermography. The experimental analysis was performed at several excitation frequencies to investigate the sample ranging from 2.946 Hz down to 0.019 Hz and the effects of each excitation frequency on defect detachability. The four point method was used in post processing of every pixel of thermal images using the MATLAB programming language. The relationship between the phase contrast with defects depth and area was examined. Finally, phase contrast method was used to calculate the defects depth considering the thermal diffusivity of the material being inspected and the excitation frequency for which the defect becomes visible. The obtained results demonstrated the effectiveness of Lock-in infrared thermography as a powerful measurement technique for the inspection of Glass fiber reinforced plastic structures.

  10. Flexural Behavior of RC Members Using Externally Bonded Aluminum-Glass Fiber Composite Beams

    Ki-Nam Hong

    2014-03-01

    Full Text Available This study concerns improvement of flexural stiffness/strength of concrete members reinforced with externally bonded, aluminum-glass fiber composite (AGC beams. An experimental program, consisting of seven reinforced concrete slabs and seven reinforced concrete beams strengthened in flexure with AGC beams, was initiated under four-point bending in order to evaluate three parameters: the cross-sectional shape of the AGC beam, the glass fiber fabric array, and the installation of fasteners. The load-deflection response, strain distribution along the longitudinal axis of the beam, and associated failure modes of the tested specimens were recorded. It was observed that the AGC beam led to an increase of the initial cracking load, yielding load of the tension steels and peak load. On the other hand, the ductility of some specimens strengthened was reduced by more than 50%. The A-type AGC beam was more efficient in slab specimens than in beam specimens and the B-type was more suitable for beam specimens than for slabs.

  11. Amorphous silicon thin-film solar cells on glass fiber textiles

    Plentz, Jonathan, E-mail: jonathan.plentz@leibniz-ipht.de; Andrä, Gudrun; Pliewischkies, Torsten; Brückner, Uwe; Eisenhawer, Björn; Falk, Fritz

    2016-02-15

    Graphical abstract: - Highlights: • Amorphous silicon solar cells on textile glass fiber fabrics are demonstrated. • Open circuit voltages of 883 mV show shunt-free contacting on non-planar fabrics. • Short-circuit current densities of 3.7 mA/cm{sup 2} are limited by transmission losses. • Fill factors of 43.1% and pseudo fill factors of 70.2% show high series resistance. • Efficiencies of 1.4% and pseudo efficiencies of 2.1% realized on textile fabrics. - Abstract: In this contribution, amorphous silicon thin-film solar cells on textile glass fiber fabrics for smart textiles are prepared and the photovoltaic performance is characterized. These solar cells on fabrics delivered open circuit voltages up to 883 mV. This shows that shunt-free contacting of the solar cells was successful, even in case of non-planar fabrics. The short-circuit current densities up to 3.7 mA/cm{sup 2} are limited by transmission losses in a 10 nm thin titanium layer, which was used as a semi-transparent contact. The low conductivity of this layer limits the fill factor to 43.1%. Pseudo fill factors, neglecting the series resistance, up to 70.2% were measured. Efficiencies up to 1.4% and pseudo efficiencies up to 2.1% were realized on textile fabrics. A transparent conductive oxide could further improve the efficiency to above 5%.

  12. Study on the influence of design parameters on the damping property of glass fiber reinforced epoxy composite

    Bhattacharjee, A.; Nanda, B. K.

    2018-04-01

    Fiber reinforced composites are widely used in industrial applications due to their high strength, light weight and ease in manufacturing. In applications such as automotive, aerospace and structural parts, the components are subjected to unwanted vibrations which reduce their service life, accuracy as well as increases noise. Therefore, it is essential to avoid the detrimental effects of vibrations by enhancing their damping characteristics. The current research deals with estimating the damping properties of Glass fiber reinforced epoxy (GFRE) composites. Processing of the GFRE composites is carried out using hand-lay technique. Various design parameters such as number of glass fiber layers, orientation of fibers and weight ratio are varied while manufacturing GFRE composites. The effects of variation of these design parameters on damping property of GFRE composites are studied extensively.

  13. Mechanical Property Evaluation of Palm/Glass Sandwiched Fiber Reinforced Polymer Composite in Comparison with few natural composites

    Raja Dhas, J. Edwin; Pradeep, P.

    2017-10-01

    Natural fibers available plenty can be used as reinforcements in development of eco friendly polymer composites. The less utilized palm leaf stalk fibers sandwiched with artificial glass fibers was researched in this work to have a better reinforcement in preparing a green composite. The commercially available polyester resin blend with coconut shell filler in nano form was used as matrix to sandwich these composites. Naturally available Fibers of palm leaf stalk, coconut leaf stalk, raffia and oil palm were extracted and treated with potassium permanganate solution which enhances the properties. For experimentation four different plates were fabricated using these fibers adopting hand lay-up method. These sandwiched composite plates are further machined to obtain ASTM standards Specimens which are mechanically tested as per standards. Experimental results reveal that the alkali treated palm leaf stalk fiber based polymer composite shows appreciable results than the others. Hence the developed composite can be recommended for fabrication of automobile parts.

  14. The high efficiency steel filters for nuclear air cleaning

    Bergman, W.; Larsen, G.; Lopez, R.; Williams, K.; Violet, C.

    1990-08-01

    We have, in cooperation with industry, developed high-efficiency filters made from sintered stainless-steel fibers for use in several air-cleaning applications in the nuclear industry. These filters were developed to overcome the failure modes in present high-efficiency particulate air (HEPA) filters. HEPA filters are made from glass paper and glue, and they may fail when they get hot or wet and when they are overpressured. In developing our steel filters, we first evaluated the commercially available stainless-steel filter media made from sintered powder and sintered fiber. The sintered-fiber media performed much better than sintered-powder media, and the best media had the smallest fiber diameter. Using the best media, we then built prototype filters for venting compressed gases and evaluated them in our automated filter tester. 12 refs., 20 figs

  15. High efficiency steel filters for nuclear air cleaning

    Bergman, W.; Conner, J.; Larsen, G.; Lopez, R.; Turner, C.; Vahla, G.; Violet, C.; Williams, K.

    1991-01-01

    The authors have, in cooperation with industry, developed high-efficiency filters made from sintered stainless-steel fibers for use in several air-cleaning applications in the nuclear industry. These filters were developed to overcome the failure modes in present high-efficiently particulate air (HEPA) filters. HEPA filters are made from glass paper and glue, and they may fail when they get hot or wet and when they are overpressured. In developing steel filters, they first evaluated the commercially available stainless-steel filter media made from sintered powder and sintered fiber. The sintered-fiber media performed much better than sintered-powder media, and the best media had the smallest fiber diameter. Using the best media, prototype filters were then built for venting compressed gases and evaluated in their automated filter tester

  16. Push-out bond strengths of different dental cements used to cement glass fiber posts.

    Pereira, Jefferson Ricardo; Lins do Valle, Accácio; Ghizoni, Janaina Salomon; Lorenzoni, Fábio César; Ramos, Marcelo Barbosa; Barbosa, Marcelo Ramos; Dos Reis Só, Marcus Vinícius

    2013-08-01

    Since the introduction of glass fiber posts, irreversible vertical root fractures have become a rare occurrence; however, adhesive failure has become the primary failure mode. The purpose of this study was to evaluate the push-out bond strength of glass fiber posts cemented with different luting agents on 3 segments of the root. Eighty human maxillary canines with similar root lengths were randomly divided into 8 groups (n=10) according to the cement assessed (Rely X luting, Luting and Lining, Ketac Cem, Rely X ARC, Biscem, Duo-link, Rely X U100, and Variolink II). After standardized post space preparation, the root dentin was pretreated for dual-polymerizing resin cements and untreated for the other cements. The mixed luting cement paste was inserted into post spaces with a spiral file and applied to the post surface that was seated into the canal. After 7 days, the teeth were sectioned perpendicular to their long axis into 1-mm-thick sections. The push-out test was performed at a speed of 0.5 mm/min until extrusion of the post occurred. The results were evaluated by 2-way ANOVA and the all pairwise multiple comparison procedures (Tukey test) (α=.05). ANOVA showed that the type of interaction between cement and root location significantly influenced the push-out strength (Pcements and glass ionomer cements showed significantly higher values compared to dual-polymerizing resin cements. In all root segments, dual-polymerizing resin cements provided significantly lower bond strength. Significant differences among root segments were found only for Duo-link cement. Copyright © 2013 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

  17. Improvement of the skin sparing characteristics of the clinac 4 by the use of leaded glass electron filters

    Ames, T.E.; Saylor, W.; Dillard, M.

    1977-01-01

    Ionization chamber measurements were taken to determine the Relative Skin Dose from the Varian Clinac 4 (lead flattening filter). The effect of blocking tray material, field size, and scatterer-skin distance on the relative skin dose was investigated both on and off the central axis. It was found that the leaded glass tray enhanced the skin sparing effect of the beam by 25 to 30 percent

  18. Bioactive Glass Fiber Reinforced Starch-Polycaprolactone Composite for Bone Applications

    Jukola, H.; Nikkola, L.; Tukiainen, M.; Kellomaeki, M.; Ashammakhi, N.; Gomes, M. E.; Reis, R. L.; Chiellini, F.; Chiellini, E.

    2008-01-01

    For bone regeneration and repair, combinations of different materials are often needed. Biodegradable polymers are often combined with osteoconductive materials, such as bioactive glass (BaG), which can also improve the mechanical properties of the composite. The aim of this study was to develop and characterize BaG fiber-reinforced starch-poly-ε-caprolactone (SPCL) composite. Sheets of SPCL (30/70 wt%) were produced using single-screw extrusion. They were then cut and compression molded in layers with BaG fibers to form composite structures of different combinations. Thermal, mechanical, and degradation properties of the composites were studied. The actual amount of BaG in the composites was determined using combustion tests. A strong endothermic peak indicating melting at about 56 deg. C was observed by differential scanning calorimetry (DSC) analysis. Thermal gravimetry analysis (TGA) showed that thermal decomposition of SPCL started at 325 deg. C with the decomposition of starch and continued at 400 deg. C with the degradation of polycaprolactone (PCL). Initial mechanical properties of the reinforced composites were at least 50% better than the properties of the non-reinforced composites. However, the mechanical properties of the composites after two weeks of hydrolysis were comparable to those of the non-reinforced samples. During the six weeks' hydrolysis the mass of the composites had decreased only by about 5%. The amount of glass in the composites remained the same for the six-week period of hydrolysis. In conclusion, it is possible to enhance the initial mechanical properties of SPCL by reinforcing it with BaG fibers. However, the mechanical properties of the composites are only sufficient for use as filler material and they need to be further improved to allow long-lasting bone applications

  19. Bioactive Glass Fiber Reinforced Starch-Polycaprolactone Composite for Bone Applications

    Jukola, H.; Nikkola, L.; Gomes, M. E.; Chiellini, F.; Tukiainen, M.; Kellomäki, M.; Chiellini, E.; Reis, R. L.; Ashammakhi, N.

    2008-02-01

    For bone regeneration and repair, combinations of different materials are often needed. Biodegradable polymers are often combined with osteoconductive materials, such as bioactive glass (BaG), which can also improve the mechanical properties of the composite. The aim of this study was to develop and characterize BaG fiber-reinforced starch-poly-ɛ-caprolactone (SPCL) composite. Sheets of SPCL (30/70 wt%) were produced using single-screw extrusion. They were then cut and compression molded in layers with BaG fibers to form composite structures of different combinations. Thermal, mechanical, and degradation properties of the composites were studied. The actual amount of BaG in the composites was determined using combustion tests. A strong endothermic peak indicating melting at about 56 °C was observed by differential scanning calorimetry (DSC) analysis. Thermal gravimetry analysis (TGA) showed that thermal decomposition of SPCL started at 325 °C with the decomposition of starch and continued at 400 °C with the degradation of polycaprolactone (PCL). Initial mechanical properties of the reinforced composites were at least 50% better than the properties of the non-reinforced composites. However, the mechanical properties of the composites after two weeks of hydrolysis were comparable to those of the non-reinforced samples. During the six weeks' hydrolysis the mass of the composites had decreased only by about 5%. The amount of glass in the composites remained the same for the six-week period of hydrolysis. In conclusion, it is possible to enhance the initial mechanical properties of SPCL by reinforcing it with BaG fibers. However, the mechanical properties of the composites are only sufficient for use as filler material and they need to be further improved to allow long-lasting bone applications.

  20. Glass fiber-reinforced thermoplastics for use in metal-free removable partial dentures: combined effects of fiber loading and pigmentation on color differences and flexural properties.

    Tanimoto, Yasuhiro; Nagakura, Manamu; Nishiyama, Norihiro

    2018-02-21

    The purpose of this study was to investigate the combined effects of fiber loading and pigmentation on the color differences and flexural properties of glass fiber-reinforced thermoplastics (GFRTPs), for use in non-metal clasp dentures (NMCDs). The GFRTPs consisted mainly of E-glass fibers, a polypropylene matrix, and a coloring pigment: the GFRTPs with various fiber loadings (0, 10, and 20mass%) and pigmentations (0, 1, 2, and 4mass%) were fabricated by using an injection molding. The color differences of GFRTPs were measured based on the Commission Internationale de l'Eclairage (CIE) Lab color system, by comparing with a commercially available NMCD. The flexural properties of GFRTPs were evaluated by using a three-point bending test, according to International Standards Organization (ISO) specification number 20795-1. The visible colors of GFRTPs with pigment contents of 2mass% were acceptable for gingival color, and the glass fibers harmonized well with the resins. The ΔE* values of the GFRTPs with pigment contents of 2mass% obtained by using the CIE Lab system were lowest at all fiber loadings. For GFRTPs with fiber contents of 10 and 20mass% at 2mass% pigment content, these GFRTPs surpassed the ISO 20795-1 specification regarding flexural strength (> 60MPa) and modulus (> 1.5GPa). A combination of the results of color difference evaluation and mechanical examination indicates that the GFRTPs with fiber contents of 10 or 20mass%, and with pigment contents of 2mass% have acceptable esthetic appearance and sufficient rigidity for NMCDs. Copyright © 2018 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  1. Flexural creep of coated SiC-fiber-reinforced glass-ceramic composites

    Sun, E.Y.

    1995-01-01

    This study reports the flexural creep behavior of a fiber-reinforced glass-ceramic and associated changes in microstructure. SiC fibers were coated with a dual layer of SiC/BN to provide a weak interface that was stable at high temperatures. Flexural creep, creep-rupture, and creep-strain recovery experiments were conducted on composite material and barium-magnesium aluminosilicate matrix from 1,000 to 1,200 C. Below 1,130 C, creep rates were extremely low (∼10 -9 s -1 ), preventing accurate measurement of the stress dependence. Above 1,130 C, creep rates were in the 10 -8 s -1 range. The creep-rupture strength of the composite at 1,100 C was about 75--80% of the fast fracture strength. Creep-strain recovery experiments showed recovery of up to 90% under prolonged unloading. Experimental creep results from the composite and the matrix were compared, and microstructural observations by TEM were employed to assess the effectiveness of the fiber coatings and to determine the mechanism(s) of creep deformation and damage

  2. Flexible, Heat-Resistant, and Flame-Retardant Glass Fiber Nonwoven/Glass Platelet Composite Separator for Lithium-Ion Batteries

    Ulrich Schadeck

    2018-04-01

    Full Text Available A new type of high-temperature stable and self-supporting composite separator for lithium-ion batteries was developed consisting of custom-made ultrathin micrometer-sized glass platelets embedded in a glass fiber nonwoven together with a water-based sodium alginate binder. The physical and electrochemical properties were investigated and compared to commercial polymer-based separators. Full-cell configuration cycling tests at different current rates were performed using graphite and lithium iron phosphate as electrode materials. The glass separator was high-temperature tested and showed a stability up to at least 600 °C without significant shrinking. Furthermore, it showed an exceptional wettability for non-aqueous electrolytes. The electrochemical performance was excellent compared to commercially available polymer-based separators. The results clearly show that glass platelets integrated into a glass fiber nonwoven performs remarkably well as a separator material in lithium-ion batteries and show high-temperature stability.

  3. Thermostimulated transitions of radiation colour centers in fiber light guides on the base of pure quartz glass

    Abramov, A.V.; Dianov, E.M.; Karpechev, V.N.; Kornienko, L.S.; Rybaltovskij, A.O.; Chernov, P.V.

    1987-01-01

    Study on properties and characteristics of induced absorption (IA) in glass fiber light guides (GFLG) with a pure quartz glass core is continued. Effect of thermal-stimulated construction of colour radiation centers (CRC) giving induced absorption bands at 670, 550, and 380 nm has been detected. Effective temperatures of these IA band annealings have been determined as well as bands at 340 nm and induced absorption IR edge. Positions of IA band halfwidths and maxima on the assumption that IA bands have the Gauss form. It is assumed that CRC photo- and thermostimulated construction may occur with participation of physically dissolved in a glass grid gases or their radiolysis products

  4. Formation mechanism of a silane-PVA/PVAc complex film on a glass fiber surface.

    Repovsky, Daniel; Jane, Eduard; Palszegi, Tibor; Slobodnik, Marek; Velic, Dusan

    2013-10-21

    Mechanical properties of glass fiber reinforced composite materials are affected by fiber sizing. A complex film formation, based on a silane film and PVA/PVAc (polyvinyl alcohol/polyvinyl acetate) microspheres on a glass fiber surface is determined at 1) the nanoscale by using atomic force microscopy (AFM), and 2) the macroscale by using the zeta potential. Silane groups strongly bind through the Si-O-Si bond to the glass surface, which provides the attachment mechanism as a coupling agent. The silane groups form islands, a homogeneous film, as well as empty sites. The average roughness of the silanized surface is 6.5 nm, whereas it is only 0.6 nm for the non-silanized surface. The silane film vertically penetrates in a honeycomb fashion from the glass surface through the deposited PVA/PVAc microspheres to form a hexagonal close pack structure. The silane film not only penetrates, but also deforms the PVA/PVAc microspheres from the spherical shape in a dispersion to a ellipsoidal shape on the surface with average dimensions of 300/600 nm. The surface area value Sa represents an area of PVA/PVAc microspheres that are not affected by the silane penetration. The areas are found to be 0.2, 0.08, and 0.03 μm(2) if the ellipsoid sizes are 320/570, 300/610, and 270/620 nm for silane concentrations of 0, 3.8, and 7.2 μg mL(-1), respectively. The silane film also moves PVA/PVAc microspheres in the process of complex film formation, from the low silane concentration areas to the complex film area providing enough silane groups to stabilize the structure. The values for the residual silane honeycomb structure heights (Ha ) are 6.5, 7, and 12 nm for silane concentrations of 3.8, 7.2, and 14.3 μg mL(-1), respectively. The pH-dependent zeta-potential results suggest a specific role of the silane groups with effects on the glass fiber surface and also on the PVA/PVAc microspheres. The non-silanized glass fiber surface and the silane film have similar zeta potentials ranging

  5. Watt-level ~2 μm laser output in Tm3+-doped tungsten tellurite glass double-cladding fiber.

    Li, Kefeng; Zhang, Guang; Hu, Lili

    2010-12-15

    We report, for the first time to the best of our knowledge, a watt level cw fiber laser at ~2 μm from a piece of 40-cm-long newly developed highly thulium-doped (3.76 × 10(20) ions/cm(3)) tungsten tellurite glass double cladding fiber pumped by a commercial 800 nm laser diode. The maximum output power of the fiber laser reaches 1.12 W. The slope efficiency and the optical-optical efficiency with respect to the absorbed pump are 20% and 16%, respectively. The lasing threshold is 1.46 W, and the lasing wavelength is centered at 1937 nm.

  6. Hybrid Carbon-Glass Fiber/Toughened Epoxy Thick Composite Joints Subject to Drop-Weight and Ballistic Impacts

    Liaw, Benjamin; Delale, Feridun

    2007-01-01

    ... No. DAAD19-02-R-0010 to conduct research on hybrid carbon-S2 glass fiber/toughened epoxy thick-section, hybrid interwoven composite joints subject to drop-weight and ballistic impacts. Dr. Basavaraju B. Raju of U.S...

  7. Novel Application of Glass Fibers Recovered From Waste Printed Circuit Boards as Sound and Thermal Insulation Material

    Sun, Zhixing; Shen, Zhigang; Ma, Shulin; Zhang, Xiaojing

    2013-10-01

    The aim of this study is to investigate the feasibility of using glass fibers, a recycled material from waste printed circuit boards (WPCB), as sound absorption and thermal insulation material. Glass fibers were obtained through a fluidized-bed recycling process. Acoustic properties of the recovered glass fibers (RGF) were measured and compared with some commercial sound absorbing materials, such as expanded perlite (EP), expanded vermiculite (EV), and commercial glass fiber. Results show that RGF have good sound absorption ability over the whole tested frequency range (100-6400 Hz). The average sound absorption coefficient of RGF is 0.86, which is prior to those of EP (0.81) and EV (0.73). Noise reduction coefficient analysis indicates that the absorption ability of RGF can meet the requirement of II rating for sound absorbing material according to national standard. The thermal insulation results show that RGF has a fair low thermal conductivity (0.046 W/m K), which is comparable to those of some insulation materials (i.e., EV, EP, and rock wool). Besides, an empirical dependence of thermal conductivity on material temperature was determined for RGF. All the results showed that the reuse of RGF for sound and thermal insulation material provided a promising way for recycling WPCB and obtaining high beneficial products.

  8. Partial Replacement of Glass Fiber by Woven Kenaf in Hybrid Composites and its Effect on Monotonic and Fatigue Properties

    Mohaiman Jaffar Sharba

    2016-02-01

    Full Text Available Natural–synthetic fiber hybrid composites offer a combination of high mechanical properties from the synthetic fibers and the advantages of renewable fibers to produce a material with highly specific and determined properties. In this study, plain-woven kenaf/glass reinforced unsaturated polyester (UP hybrid composites were fabricated using the hand lay-up method with a cold hydraulic press in a sandwich-configuration laminate. The glass was used as a shell with kenaf as a core, with an approximate total fiber content of 40%. Three glass/kenaf weight ratios percentages of (70/30% (H1, (55/45% (H2, and (30/70% (H3 were used to fabricate hybrid composites. Also pure glass/UP and kenaf/UP were fabricated for comparison purposes. Monotonic tests, namely tensile, compression, and flexural strengths of the composites, were performed. The morphological properties of tensile and compression failure of kenaf and hybrid composites were studied. In addition, uniaxial tensile fatigue life of hybrid composites were conducted and evaluated. The results revealed that the hybrid composite (H1 offered a good balance and the best static properties, but in tensile fatigue loading (H3 displayed low fatigue sensitivity when compared with the other hybrid composites.

  9. LABORATORY EVALUATION ON PERFORMANCE OF GLASS FIBER REINFORCED PLASTIC MORTAR PIPE CULVERTS

    Huawang Shi

    2018-04-01

    Full Text Available This paper investigated the performance and behaviour of glass fiber reinforced plastic mortar (FRPM pipes under different loading conditions. FRPM pipes with inner diameter of 1500 mm were prefabricated in factory. Mechanics performance testing (ring and axial compressive strength and elastic modulus, stiffness and fatigue test were carried out in laboratory. Ring stiffness test provided pipe stiffness (PS which is a function of geometry and material type of pipe through parallel plate loading test (PPLT. The fatigue test and micro-structure measure method were used to evaluate the durability effects of FRPM under repeated compression load. Results indicated that FRPM pipes had better mechanic performances as the road culverts under soils. It may be helpful for the design and construction of FRPM culverts.

  10. Weather ability studies of phenolic resin coated woods and glass fiber reinforced laminates

    Munir, A.; Hussain, R.; Rizvi, M.H.; Ahmed, F.

    1997-01-01

    Phenolic resins have made a major breakthrough in the field of high technology in 80's. These are now active participants of h igh tech' areas ranging from electronics, computers, communication, outer space, aerospace, advanced materials, bio materials and technology. A phenol - formaldehyde (1:1.5) resin having resin content of 70% synthesized in the laboratory has been applied for wood coating and reinforcing glass fiber. The weatherability and solvent resistance of these items have been studied and results discussed keeping in view the envisaged application for structural materials and chemical equipment. The toxic materials released during contact with solvents for chemical applications and during degradation general have been monitored. The results are discussed with reference to environmental pollution due to these resins and their composites under different conditions. (authors)

  11. Supersonic Panel Flutter Test Results for Flat Fiber-Glass Sandwich Panels with Foamed Cores

    Tuovila, W. J.; Presnell, John G., Jr.

    1961-01-01

    Flutter tests have been made on flat panels having a 1/4 inch-thick plastic-foam core covered with thin fiber-glass laminates. The testing was done in the Langley Unitary Plan wind tunnel at Mach numbers from 1.76 t o 2.87. The flutter boundary for these panels was found to be near the flutter boundary of thin metal panels when compared on the basis of an equivalent panel stiffness. The results also demonstrated that the depth of the cavity behind the panel has a pronounced influence on flutter. Changing the cavity depth from 1 1/2 inches to 1/2 inch reduced the dynamic pressure at start of flutter by 40 percent. No flutter was obtained when the spacers on the back of the panel were against the bottom of the cavity.

  12. Evaluation of Mechanical Properties of Glass Fiber Posts Subjected to Laser Surface Treatments.

    Barbosa Siqueira, Carolina; Spadini de Faria, Natália; Raucci-Neto, Walter; Colucci, Vivian; Alves Gomes, Erica

    2016-10-01

    The aim of this study was to evaluate the influence of laser irradiation on flexural strength, elastic modulus, and surface roughness and morphology of glass fiber posts (GFPs). Laser treatment of GFPs has been introduced to improve its adhesion properties. A total of 40 GFPs were divided into 4 groups according to the irradiation protocol: GC-no irradiation, GYAG-irradiation with erbium:yttrium-aluminum-garnet [Er:YAG], GCR-irradiation with erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG), and GDI-irradiation with diode laser. The GFP roughness and morphology were evaluated through laser confocal microscopy before and after surface treatment. Three-point bending flexural test measured flexural strength and elastic modulus. Data about elastic modulus and flexural strength were subjected to one-way ANOVA and Bonferroni test (p properties of GFPs.

  13. Flexural strengthening of Reinforced Concrete (RC) Beams Retrofitted with Corrugated Glass Fiber Reinforced Polymer (GFRP) Laminates

    Aravind, N.; Samanta, Amiya K.; Roy, Dilip Kr. Singha; Thanikal, Joseph V.

    2015-01-01

    Strengthening the structural members of old buildings using advanced materials is a contemporary research in the field of repairs and rehabilitation. Many researchers used plain Glass Fiber Reinforced Polymer (GFRP) sheets for strengthening Reinforced Concrete (RC) beams. In this research work, rectangular corrugated GFRP laminates were used for strengthening RC beams to achieve higher flexural strength and load carrying capacity. Type and dimensions of corrugated profile were selected based on preliminary study using ANSYS software. A total of twenty one beams were tested to study the load carrying capacity of control specimens and beams strengthened with plain sheets and corrugated laminates using epoxy resin. This paper presents the experimental and theoretical study on flexural strengthening of Reinforced Concrete (RC) beams using corrugated GFRP laminates and the results are compared. Mathematical models were developed based on the experimental data and then the models were validated.

  14. Glass fiber reinforced polyester in the works of Tous and Fargas

    D. Hernández Falagán

    2017-06-01

    Full Text Available The architects Enric Tous (1925; t 1952 and Josep Maria Fargas (1926-2011, t 1952 achieved remarkable success during the 1960s and 1970s thanks to their commitment to technical experimentation and exploration of new construction systems. Among their most significant contributions is the incorporation of polyester reinforced with glass fiber as a material applied to solutions of light facades. This article tracks the origin, context, and results they obtained with this material. We propose an approach to the GRC material through the experience developed by the architects, analyzing the characteristics and specific implications of the systems proposed in their projects. Through this reading, the industrial initiative implemented by Tous and Fargas is put into value, and the key aspects that limited the progression of the construction system are detected.

  15. Measurement and analysis of thrust force in drilling sisal-glass fiber reinforced polymer composites

    Ramesh, M.; Gopinath, A.

    2017-05-01

    Drilling of composite materials is difficult when compared to the conventional materials because of its in-homogeneous nature. The force developed during drilling play a major role in the surface quality of the hole and minimizing the damages around the surface. This paper focuses the effect of drilling parameters on thrust force in drilling of sisal-glass fiber reinforced polymer composite laminates. The quadratic response models are developed by using response surface methodology (RSM) to predict the influence of cutting parameters on thrust force. The adequacy of the models is checked by using the analysis of variance (ANOVA). A scanning electron microscope (SEM) analysis is carried out to analyze the quality of the drilled surface. From the results, it is found that, the feed rate is the most influencing parameter followed by spindle speed and the drill diameter is the least influencing parameter on the thrust force.

  16. The mechanical and thermal characteristics of phenolic foam reinforced with kaolin powder and glass fiber fabric

    Xiao, Wenya; Huang, Zhixiong; Ding, Jie

    2017-12-01

    In this work, kaolin powder and glass fiber fabric were added to PF in order to improve its thermal stability and mechanical property. Micro-structures of carbonized PF with kaolin powder were inspected by scanning electron microscopy (SEM) to demonstrate the filler’s pinning effect. SEM results illustrated modified PF had well morphology after high-temperature heat treatment. The Fourier transform infrared spectrometer (FTIR) test was carried out and found that kaolin powder only physically dispersed in PF. The compression test and thermal weight loss test were done on two groups of modified PF (Group A: add powder and fabric; Group B: add powder only). Results showed that all modified PF were better than pure PF, while foams with powder and fabric showed better mechanical characteristic and thermal stability compared with foams with powder only.

  17. A Laboratory Investigation on Shear Strength Behavior of Sandy Soil: Effect of Glass Fiber and Clinker Residue Content

    Bouaricha Leyla

    2017-12-01

    Full Text Available A study was undertaken to investigate the shear strength parameters of treated sands reinforced with randomly distributed glass fibers by carrying out direct shear test after seven days curing periods. Firstly, we studied the fiber content and fiber length effect on the peak shear strength on samples. The second part gives a parametric analysis on the effect of glass fiber and clinker residue content on the shear strength parameters for two types of uniform Algerian sands having different particle sizes (Chlef sand and Rass sand with an average relative density Dr = 50%. Finally, the test results show that the combination of glass fiber and clinker residue content can effectively improve the shear strength parameters of soil in comparison with unreinforced soil. For instance, there is a significant gain for the cohesion and friction angle of reinforced sand of Chlef. Compared to unreinforced sand, the cohesion for sand reinforced with different ratios of clinker residue increased by 4.36 to 43.08 kPa for Chlef sand and by 3.1 to 28.64 kPa for Rass sand. The feature friction angles increased from 38.73° to 43.01° (+4.28°, and after the treatment, clinker residue content of soil evaluated to 5% (WRC = 5%.

  18. A Laboratory Investigation on Shear Strength Behavior of Sandy Soil: Effect of Glass Fiber and Clinker Residue Content

    Bouaricha, Leyla; Henni, Ahmed Djafar; Lancelot, Laurent

    2017-12-01

    A study was undertaken to investigate the shear strength parameters of treated sands reinforced with randomly distributed glass fibers by carrying out direct shear test after seven days curing periods. Firstly, we studied the fiber content and fiber length effect on the peak shear strength on samples. The second part gives a parametric analysis on the effect of glass fiber and clinker residue content on the shear strength parameters for two types of uniform Algerian sands having different particle sizes (Chlef sand and Rass sand) with an average relative density Dr = 50%. Finally, the test results show that the combination of glass fiber and clinker residue content can effectively improve the shear strength parameters of soil in comparison with unreinforced soil. For instance, there is a significant gain for the cohesion and friction angle of reinforced sand of Chlef. Compared to unreinforced sand, the cohesion for sand reinforced with different ratios of clinker residue increased by 4.36 to 43.08 kPa for Chlef sand and by 3.1 to 28.64 kPa for Rass sand. The feature friction angles increased from 38.73° to 43.01° (+4.28°), and after the treatment, clinker residue content of soil evaluated to 5% (WRC = 5%).

  19. Thermo-mechanical characterization of siliconized E-glass fiber/hematite particles reinforced epoxy resin hybrid composite

    Arun Prakash, V.R., E-mail: vinprakash101@gmail.com; Rajadurai, A., E-mail: rajadurai@annauniv.edu.in

    2016-10-30

    Highlights: • Particles dimension have reduced using Ball milling process. • Importance of surface modification was explored. • Surface modification has been done to improve adhesion of fiber/particles with epoxy. • Mechanical properties has been increased by adding modified fiber and particles. • Thermal properties have been increased. - Abstract: In this present work hybrid polymer (epoxy) matrix composite has been strengthened with surface modified E-glass fiber and iron(III) oxide particles with varying size. The particle sizes of 200 nm and <100 nm has been prepared by high energy ball milling and sol-gel methods respectively. To enhance better dispersion of particles and improve adhesion of fibers and fillers with epoxy matrix surface modification process has been done on both fiber and filler by an amino functional silane 3-Aminopropyltrimethoxysilane (APTMS). Crystalline and functional groups of siliconized iron(III) oxide particles were characterized by XRD and FTIR spectroscopy analysis. Fixed quantity of surface treated 15 vol% E-glass fiber was laid along with 0.5 and 1.0 vol% of iron(III) oxide particles into the matrix to fabricate hybrid composites. The composites were cured by an aliphatic hardener Triethylenetetramine (TETA). Effectiveness of surface modified particles and fibers addition into the resin matrix were revealed by mechanical testing like tensile testing, flexural testing, impact testing, inter laminar shear strength and hardness. Thermal behavior of composites was evaluated by TGA, DSC and thermal conductivity (Lee’s disc). The scanning electron microscopy was employed to found shape and size of iron(III) oxide particles adhesion quality of fiber with epoxy matrix. Good dispersion of fillers in matrix was achieved with surface modifier APTMS. Tensile, flexural, impact and inter laminar shear strength of composites was improved by reinforcing surface modified fiber and filler. Thermal stability of epoxy resin was improved

  20. Application of sandwich honeycomb carbon/glass fiber-honeycomb composite in the floor component of electric car

    Sukmaji, I. C.; Wijang, W. R.; Andri, S.; Bambang, K.; Teguh, T.

    2017-01-01

    Nowadays composite is a superior material used in automotive component due to its outstanding mechanical behavior. The sandwich polypropylene honeycomb core with carbon/glass fiber composite skin (SHCG) as based material in a floor component of electric car application is investigated in the present research. In sandwich structure form, it can absorb noise better compare with the conventional material [1]. Also in present paper, Finite Element Analysis (FEA) of SHCG as based material for floor component of the electric car is analyzed. The composite sandwich is contained with a layer uniform carbon fiber and mixing non-uniform carbon-glass fiber in upper and lower skin. Between skins of SHCG are core polypropylene honeycomb that it have good flexibility to form following dies profile. The variables of volume fraction ratio of carbon/glass fiber in SHCG skin are 20/80%, 30/70%, and 50/50%. The specimen of SHCG is tested using the universal testing machine by three points bending method refers to ASTM C393 and ASTM C365. The cross point between tensile strength to the volume fraction the mixing carbon/glass line and ratio cost line are the searched material with good mechanical performance and reasonable cost. The point is 30/70 volume fraction of carbon/glass fiber. The result of the testing experiment is become input properties of model structure sandwich in FEA simulation. FEA simulation approach is conducted to find critical strength and factor of complex safety geometry against varied distributed passenger loads of a floor component the electric car. The passenger loads variable are 80, 100, 150, 200, 250 and 300 kg.

  1. Ultra-high tunable liquid crystal-plasmonic photonic crystal fiber polarization filter.

    Hameed, Mohamed Farhat O; Heikal, A M; Younis, B M; Abdelrazzak, Maher; Obayya, S S A

    2015-03-23

    A novel ultra-high tunable photonic crystal fiber (PCF) polarization filter is proposed and analyzed using finite element method. The suggested design has a central hole infiltrated with a nematic liquid crystal (NLC) that offers high tunability with temperature and external electric field. Moreover, the PCF is selectively filled with metal wires into cladding air holes. Results show that the resonance losses and wavelengths are different in x and y polarized directions depending on the rotation angle φ of the NLC. The reported filter of compact device length 0.5 mm can achieve 600 dB / cm resonance losses at φ = 90° for x-polarized mode at communication wavelength of 1300 mm with low losses of 0.00751 dB / cm for y-polarized mode. However, resonance losses of 157.71 dB / cm at φ = 0° can be achieved for y-polarized mode at the same wavelength with low losses of 0.092 dB / cm for x-polarized mode.

  2. Detection of retinal nerve fiber layer defects in retinal fundus images using Gabor filtering

    Hayashi, Yoshinori; Nakagawa, Toshiaki; Hatanaka, Yuji; Aoyama, Akira; Kakogawa, Masakatsu; Hara, Takeshi; Fujita, Hiroshi; Yamamoto, Tetsuya

    2007-03-01

    Retinal nerve fiber layer defect (NFLD) is one of the most important findings for the diagnosis of glaucoma reported by ophthalmologists. However, such changes could be overlooked, especially in mass screenings, because ophthalmologists have limited time to search for a number of different changes for the diagnosis of various diseases such as diabetes, hypertension and glaucoma. Therefore, the use of a computer-aided detection (CAD) system can improve the results of diagnosis. In this work, a technique for the detection of NFLDs in retinal fundus images is proposed. In the preprocessing step, blood vessels are "erased" from the original retinal fundus image by using morphological filtering. The preprocessed image is then transformed into a rectangular array. NFLD regions are observed as vertical dark bands in the transformed image. Gabor filtering is then applied to enhance the vertical dark bands. False positives (FPs) are reduced by a rule-based method which uses the information of the location and the width of each candidate region. The detected regions are back-transformed into the original configuration. In this preliminary study, 71% of NFLD regions are detected with average number of FPs of 3.2 per image. In conclusion, we have developed a technique for the detection of NFLDs in retinal fundus images. Promising results have been obtained in this initial study.

  3. Fluid flow analysis of E-glass fiber reinforced pipe joints in oil and gas industry

    Bobba, Sujith; Leman, Z.; Zainuddin, E. S.; Sapuan, S. M.

    2018-04-01

    Glass Fiber reinforced composites have become increasingly important over the past few years and now they are the first choice materials for fabricating pipes with low weight in combination with high strength and stiffness. In Oil And Gas Industry, The Pipelines transporting heavy crude oil are subjected to variable pressure waves causing fluctuating stress levels in the pipes. Computational Fluid Dynamics (CFD) analysis was performed using solid works flow stimulation software to study the effects of these pressure waves on some specified joints in the pipes. Depending on the type of heavy crude oil being used, the flow behavior indicated a considerable degree of stress levels in certain connecting joints, causing the joints to become weak over a prolonged period of use. This research proposes a new perspective that is still required to be developed regarding the change of the pipe material, fiber winding angle in those specified joints and finally implementing cad wind technology to check the output result of the stress levels so that the life of the pipes can be optimized.

  4. Fabrication of polycrystalline silicon thin films on glass substrates using fiber laser crystallization

    Dao, Vinh Ai; Han, Kuymin; Heo, Jongkyu; Kyeong, Dohyeon; Kim, Jaehong; Lee, Youngseok; Kim, Yongkuk; Jung, Sungwook; Kim, Kyunghae [Information and Communication Device Laboratory, School of Information and Communication Engineering, Sungkyunkwan University (Korea, Republic of); Yi, Junsin, E-mail: yi@yurim.skku.ac.k [Information and Communication Device Laboratory, School of Information and Communication Engineering, Sungkyunkwan University (Korea, Republic of)

    2009-05-29

    Laser crystallization of amorphous silicon (a-Si), using a fiber laser of {lambda} = 1064 nm wavelength, was investigated. a-Si films with 50 nm thickness deposited on glass were prepared by a plasma enhanced chemical vapor deposition. The infrared fundamental wave ({lambda} = 1064 nm) is not absorbed by amorphous silicon (a-Si) films. Thus, different types of capping layers (a-CeO{sub x}, a-SiN{sub x}, and a-SiO{sub x}) with a desired refractive index, n and thickness, d were deposited on the a-Si surface. Crystallization was a function of laser energy density, and was performed using a fiber laser. The structural properties of the crystallized films were measured via Raman spectra, a scanning electron microscope (SEM), and an atomic force microscope (AFM). The relationship between film transmittance and crystallinity was discussed. As the laser energy density increased from 10-40 W, crystallinity increased from 0-90%. However, the higher laser density adversely affected surface roughness and uniformity of the grain size. We found that favorable crystallization and uniformity could be accomplished at the lower energy density of 30 W with a-SiO{sub x} as the capping layer.

  5. Irradiation conditions for fiber laser bonding of HAp-glass ceramics with bovine cortical bone.

    Tadano, Shigeru; Yamada, Satoshi; Kanaoka, Masaru

    2014-01-01

    Orthopedic implants are widely used to repair bones and to replace articulating joint surfaces. It is important to develop an instantaneous technique for the direct bonding of bone and implant materials. The aim of this study was to develop a technique for the laser bonding of bone with an implant material like ceramics. Ceramic specimens (10 mm diameter and 1 mm thickness) were sintered with hydroxyapatite and MgO-Al2O3-SiO2 glass powders mixed in 40:60 wt% proportions. A small hole was bored at the center of a ceramic specimen. The ceramic specimen was positioned onto a bovine bone specimen and a 5 mm diameter area of the ceramic specimen was irradiated using a fiber laser beam (1070-1080 nm wavelength). As a result, the bone and the ceramic specimens bonded strongly under the irradiation conditions of a 400 W laser power and a 1.0 s exposure time. The maximum shear strength was 5.3 ± 2.3 N. A bonding substance that penetrated deeply into the bone specimen was generated around the hole in the ceramic specimen. On using the fiber laser, the ceramic specimen instantaneously bonded to the bone specimen. Further, the irradiation conditions required for the bonding were investigated.

  6. Process monitoring of glass reinforced polypropylene laminates using fiber Bragg gratings

    Mulle, Matthieu

    2015-12-29

    Hot-press molding of glass-fiber-reinforced polypropylene (GFPP) laminates was monitored using longitudinally and transversely embedded fiber Bragg gratings (FBGs) at different locations in unidirectional laminates. The optical sensors proved to efficiently characterize some material properties; for example, strain variations could be related physical change of the laminate, revealing key transition points such as the onset of melt or solidification. These results were confirmed through some comparison with traditional techniques such as differential scanning calorimetry. After the GFPP plate was released from the mold, residual strains were estimated. Because cooling rate is an important process parameter in thermoplastics, affecting crystallinity and ultimately residual strain, two different conditions (22 and 3 °C/min) were investigated. In the longitudinal direction, results were nearly identical while in the transverse direction results showed a 20% discrepancy. Coefficients of thermal expansion (CTE) were also identified during a post-process heating procedure using the embedded FBGs and compared to the results of a thermo-mechanical analysis. Again, dissimilarities were observed for the transverse direction. With regards to through the thickness properties, no differences were observed for residual strains or for CTEs.

  7. Micromechanical modeling of short glass-fiber reinforced thermoplastics-Isotropic damage of pseudograins

    Kammoun, S.; Brassart, L.; Doghri, I.; Delannay, L.; Robert, G.

    2011-01-01

    A micromechanical damage modeling approach is presented to predict the overall elasto-plastic behavior and damage evolution in short fiber reinforced composite materials. The practical use of the approach is for injection molded thermoplastic parts reinforced with short glass fibers. The modeling is proceeded as follows. The representative volume element is decomposed into a set of pseudograins, the damage of which affects progressively the overall stiffness and strength up to total failure. Each pseudograin is a two-phase composite with aligned inclusions having same aspect ratio. A two-step mean-field homogenization procedure is adopted. In the first step, the pseudograins are homogenized individually according to the Mori-Tanaka scheme. The second step consists in a self-consistent homogenization of homogenized pseudograins. An isotropic damage model is applied at the pseudograin level. The model is implemented as a UMAT in the finite element code ABAQUS. Model is shown to reproduce the strength and the anisotropy (Lankford coefficient) during uniaxial tensile tests on samples cut under different directions relative to the injection flow direction.

  8. Effects of Fiber Content on Mechanical Properties of CVD SiC Fiber-Reinforced Strontium Aluminosilicate Glass-Ceramic Composites

    Bansal, Narottam P.

    1996-01-01

    Unidirectional CVD SiC(f)(SCS-6) fiber-reinforced strontium aluminosilicate (SAS) glass-ceramic matrix composites containing various volume fractions, approximately 16 to 40 volume %, of fibers were fabricated by hot pressing at 1400 C for 2 h under 27.6 MPa. Monoclinic celsian, SrAl2Si2O8, was the only crystalline phase formed, with complete absence of the undesired hexacelsian phase, in the matrix. Room temperature mechanical properties were measured in 3-point flexure. The matrix microcracking stress and the ultimate strength increased with increase in fiber volume fraction, reached maximum values for V(sub f) approximately equal to 0.35, and degraded at higher fiber loadings. This degradation in mechanical properties is related to the change in failure mode, from tensile at lower V(sub f) to interlaminar shear at higher fiber contents. The extent of fiber loading did not have noticeable effect on either fiber-matrix debonding stress, or frictional sliding stress at the interface. The applicability of micromechanical models in predicting the mechanical properties of the composites was also examined. The currently available theoretical models do not appear to be useful in predicting the values of the first matrix cracking stress, and the ultimate strength of the SCS-6/SAS composites.

  9. PERBAIKAN KEKUATAN DAN DAKTILITAS KOLOM BETON BERTULANG YANG MENDAPAT BEBAN GEMPA MENGGUNAKAN GLASS FIBER REINFORCED POLYMER

    Parmo Parmo

    2014-05-01

    Full Text Available Repairing the Strength and Ductility of Reinforced Concrete Column That Got Earthquake using Gla­ss Fiber Reinforced Polymer. This study aims to identify the additional strength and ductility of reinforced concrete columns af­ter being re­­­­tro­fitted using glass fiber reinforced polymer (GFRP and got the brunt of the earth­quake. This study uses two objects tested columns, which are being tested for three times. Each column size is 350 x 350 x 1100 mm with f'c = 20.34 MPa and fy = 549.94 MPa. The tes­t­ing is performed by giving a constant axial load of 748 kN and cyclic lateral load using con­trol displacement method in order to simulate the brunt of earth­quake. The results show an in­crea­se in lateral capacity of co­lumn by 43.96%. Re­tro­­fitting the column with GFRP has a duc­tile property, which is shown by the increase of the displacement ductility by 129.14% and curvature ductility by 118.27%.   Penelitian ini ber­tujuan untuk mengetahui penambahan kekuatan dan dak­ti­li­­­­tas kolom beton bertulang se­telah diretrofit menggunakan glass fiber reinforced po­ly­­­mer (GFRP dan mendapat be­ban gempa. Penelitian ini menggunakan benda ­uji dua buah kolom dengan tiga kali pengujian. Masing-masing ukuran kolom 350 x 350 x 1100 mm dengan f’c = 20,34 MPa dan fy = 549,94 MPa. Pengujian dilakukan de­ngan memberikan beban ak­sial konstan 748 kN dan beban lateral siklik yang meng­gu­nakan metode di­splacemet con­trol untuk mensimulasikan beban gempa. Hasil pe­ne­­­litian menunjukkan pe­ningkatan kapasitas lateral pada kolom sebesar 43,96%. Retrofit kolom dengan GFRP bersifat dak­tail yang ditunjukkan dengan meningkatnya daktilitas per­pindahan sebesar 129,14% dan dak­­­tilitas kurvatur se­besar 118,27%.

  10. Effect of Reinforcement Using Stainless Steel Mesh, Glass Fibers, and Polyethylene on the Impact Strength of Heat Cure Denture Base Resin - An In Vitro Study.

    Murthy, H B Mallikarjuna; Shaik, Sharaz; Sachdeva, Harleen; Khare, Sumit; Haralur, Satheesh B; Roopa, K T

    2015-06-01

    The impact strength of denture base resin is of great concern and many approaches have been made to strengthen acrylic resin dentures. The objective of this study was to compare the impact strength of the denture base resin with and without reinforcement and to evaluate the impact strength of denture base resin when reinforced with stainless steel mesh, glass fiber, and polyethylene fibers in the woven form. The specimens (maxillary denture bases) were fabricated using a standard polyvinylsiloxane mold with conventional heat cured polymethyl methacrylate resin. The specimens were divided into four groups (n = 10). Group I specimens or control group were not reinforced. Group II specimens were reinforced with stainless steel mesh and Group III and Group IV specimens were reinforced with three percent by weight of glass fibers and polyethylene fibers in weave form respectively. All the specimens were immersed in water for 1-week before testing. The impact strength was measured with falling weight impact testing machine. One-way analysis of variance and Tukey's post-hoc test were used for statistical analysis. Highest impact strength values were exhibited by the specimens reinforced with polyethylene fibers followed by glass fibers, stainless steel mesh, and control group. Reinforcement of maxillary complete dentures showed a significant increase in impact strength when compared to unreinforced dentures. Polyethylene fibers exhibit better impact strength followed by glass fibers and stainless steel mesh. By using pre-impregnated glass and polyethylene fibers in woven form (prepregs) the impact strength of the denture bases can be increased effectively.

  11. Effects of Kenaf Fiber Orientation on Mechanical Properties and Fatigue Life of Glass/Kenaf Hybrid Composites

    Mohaiman Jaffar Sharba

    2015-12-01

    Full Text Available The objectives of this work were to investigate the effect of kenaf fiber alignment on the mechanical and fatigue properties of kenaf/glass hybrid sandwich composites. Three types of kenaf fibers were used, namely, non-woven random mat, unidirectional twisted yarn, and plain-woven kenaf. A symmetric sandwich configuration was constructed with glass as the shell and kenaf as the core with a constant kenaf/glass weight ratio of 30/70% and a volume fraction of 35%. Tensile, compression, flexural, and fully reversed fatigue tests were conducted, and a morphological study of the tensile failure surface of each hybrid composite was carried out. The non-woven mat kenaf hybrid had poor properties for all tests, while the unidirectional kenaf hybrid composite possessed higher tensile strength and similar compressive properties compared with the woven kenaf. Hybridization with kenaf fibers improved the fatigue degradation coefficient of the final composites to 6.2% and 6.4% for woven and unidirectional kenaf, respectively, compared with 7.9% for non-woven. Because woven kenaf hybrid composite is lightweight, environment friendly, and has a considerable balance in static and fatigue strengths with low fatigue sensitivity in bidirectional planes compared to glass, it is strongly recommended for structural applications.

  12. Preparation and Characterization of UPR/ LNR/ Glass Fiber Composite by using Unsaturated Polyester Resin (PET) from PET Wastes

    Siti Farhana Hisham; Ishak Ahmad; Rusli Daik

    2011-01-01

    UPR/ LNR/ glass fibre composite had been prepared by using unsaturated polyester resin (UPR) based from recycled PET product. PET waste was recycled by glycolysis process and the glycides product was then reacted with maleic anhydride to produce unsaturated polyester resin. The preparation of UPR/ LNR blends were conducted by varying the amount of LNR addition to the resin ranging from 0-7.5 % (wt). The composition of UPR/LNR blend with good mechanical properties had been selected as a matrix of the glass fiber reinforced composite. Glass fibre was also treated by (3-Amino propil)triethoxysilane as a coupling agent. From the result, the addition of 2.5 % LNR in UPR had showed the optimum mechanical and morphological properties where the elastomer particle's were well dispersed in the matrix with smaller size. The silane treatment on the glass fiber increased the tensile and impact strength values of the UPR/ LNR/ GF composite compared to untreated fiber reinforcement. (author)

  13. UV Blocking Glass: Low Cost Filters for Visible Light Photocatalytic Assessment

    Dunnill, Charles W.

    2014-01-01

    A number of commercially available art protection products have been compared and assessed for their suitability as UV blocking filters in the application of “visible light” photocatalytic research. Many groups claiming visible light photocatalytic success employ filters to block out stray UV radiation in order to justify that their photocatalysts are indeed visible light photocatalysts and not UV light photocatalysts. These filters come in varying degrees of ability and price and many author...

  14. Spectral Filtering Criteria for U-Band Test Light for In-Service Line Monitoring in Optical Fiber Networks

    Honda, Nazuki; Izumita, Hisashi; Nakamura, Minoru

    2006-06-01

    In the fiber-to-the-home era, thousands of optical fibers will have to be accommodated in the central offices of optical access networks. To reduce maintenance costs and improve the service reliability of optical fiber networks, the authors must develop an optical fiber line testing system with a function for in-service line monitoring that uses a test light with a wavelength different from the communication light wavelength. To monitor an in-service line in an optical network, the effective rejection ratio of the test light must be taken into account. This ratio depends on the spectrum of the test light from the optical time-domain reflectometer and the rejection band of the filter in front of the optical network unit. The dependence of the effective rejection ratio as a function of the sideband suppression ratio (SBSR) and of the ratio of the rejection band to the bandwidth of the sideband noise d/D is clarified. When d/D =0.1 and the target effective rejection ratio of the filter is -40 dB, the SBSR and the filter loss of the termination cable must be -70 and -43 dB, respectively, or the SBSR must be -80 dB. When d/D service line monitoring for a 10-Gb/s transmission using a 1650-nm test light with an SBSR of -80 dB is also demonstrated.

  15. Glasses

    Dyre, Jeppe

    2004-01-01

    The temperature dependence of the viscosity of most glassforming liquids is known to depart significantly from the classical Arrhenius behaviour of simple fluids. The discovery of an unexpected correlation between the extent of this departure and the Poisson ratio of the resulting glass could lead...... to new understanding of glass ageing and viscous liquid dynamics....

  16. All-fiber probe for optical coherence tomography with an extended depth of focus by a high-efficient fiber-based filter

    Qiu, Jianrong; Shen, Yi; Shangguan, Ziwei; Bao, Wen; Yang, Shanshan; Li, Peng; Ding, Zhihua

    2018-04-01

    Although methods have been proposed to maintain high transverse resolution over an increased depth range, it is not straightforward to scale down the bulk-optic solutions to minimized probes of optical coherence tomography (OCT). In this paper, we propose a high-efficient fiber-based filter in an all-fiber OCT probe to realize an extended depth of focus (DOF) while maintaining a high transverse resolution. Mode interference in the probe is exploited to modulate the complex field with controllable radial distribution. The principle of DOF extension by the fiber-based filter is theoretically analyzed. Numerical simulations are conducted to evaluate the performances of the designed probes. A DOF extension ratio of 2.6 over conventional Gaussian beam is obtainable in one proposed probe under a focused beam diameter of 4 . 6 μm. Coupling efficiencies of internal interfaces of the proposed probe are below -40 dB except the last probe-air interface, which can also be depressed to be -44 dB after minor modification in lengths for the filter. Length tolerance of the proposed probe is determined to be - 28 / + 20 μm, which is readily satisfied in fabrication. With the merits of extended-DOF, high-resolution, high-efficiency and easy-fabrication, the proposed probe is promising in endoscopic applications.

  17. Thermal stress modification in regenerated fiber Bragg grating via manipulation of glass transition temperature based on CO₂-laser annealing.

    Lai, Man-Hong; Lim, Kok-Sing; Gunawardena, Dinusha S; Yang, Hang-Zhou; Chong, Wu-Yi; Ahmad, Harith

    2015-03-01

    In this work, we have demonstrated thermal stress relaxation in regenerated fiber Bragg gratings (RFBGs) by using direct CO₂-laser annealing technique. After the isothermal annealing and slow cooling process, the Bragg wavelength of the RFBG has been red-shifted. This modification is reversible by re-annealing and rapid cooling. It is repeatable with different cooling process in the subsequent annealing treatments. This phenomenon can be attributed to the thermal stress modification in the fiber core by means of manipulation of glass transition temperature with different cooling rates. This finding in this investigation is important for accurate temperature measurement of RFBG in dynamic environment.

  18. Bond strength of resin cement to dentin and to surface-treated posts of titanium alloy, glass fiber, and zirconia

    Sahafi, Alireza; Peutzfeldt, Anne; Asmussen, Erik

    2003-01-01

    PURPOSE: To determine the effect of surface treatments on bond strength of two resin cements (ParaPost Cement and Panavia F) to posts of titanium alloy (ParaPost XH), glass fiber (ParaPost Fiber White), and zirconia (Cerapost), and to dentin. MATERIALS AND METHODS: After embedding, planar surfaces...... of posts (n = 9 to 14) and human dentin (n = 10) were obtained by grinding. The posts received one of three surface treatments: 1. roughening (sandblasting, hydrofluoric acid etching), 2. application of primer (Alloy Primer, Metalprimer II, silane), or 3. roughening followed by application of primer...

  19. Strain measurement in a concrete beam by use of the Brillouin-scattering-based distributed fiber sensor with single-mode fibers embedded in glass fiber reinforced polymer rods and bonded to steel reinforcing bars.

    Zeng, Xiaodong; Bao, Xiaoyi; Chhoa, Chia Yee; Bremner, Theodore W; Brown, Anthony W; DeMerchant, Michael D; Ferrier, Graham; Kalamkarov, Alexander L; Georgiades, Anastasis V

    2002-08-20

    The strain measurement of a 1.65-m reinforced concrete beam by use of a distributed fiber strain sensor with a 50-cm spatial resolution and 5-cm readout resolution is reported. The strain-measurement accuracy is +/-15 microepsilon (microm/m) according to the system calibration in the laboratory environment with non-uniform-distributed strain and +/-5 microepsilon with uniform strain distribution. The strain distribution has been measured for one-point and two-point loading patterns for optical fibers embedded in pultruded glass fiber reinforced polymer (GFRP) rods and those bonded to steel reinforcing bars. In the one-point loading case, the strain deviations are +/-7 and +/-15 microepsilon for fibers embedded in the GFRP rods and fibers bonded to steel reinforcing bars, respectively, whereas the strain deviation is +/-20 microepsilon for the two-point loading case.

  20. Effect of the Volume Fraction of Jute Fiber on the Interlaminar Shear Stress and Tensile Behavior Characteristics of Hybrid Glass/Jute Fiber Reinforced Polymer Composite Bar for Concrete Structures

    Chan-Gi Park

    2016-01-01

    Full Text Available Hybrid glass/jute fiber reinforced polymer (HGJFRP composite bars were manufactured for concrete structures, and their interlaminar shear stress and tensile performance were evaluated. HGJFRP composite bars were manufactured using a combination of pultrusion and braiding processes. Jute fiber was surface-treated with a silane coupling agent. The mixing ratio of the fiber to the vinyl ester used in the HGJFRP composite bars was 7 : 3. Jute fiber was used to replace glass fiber in proportions of 0, 30, 50, 70, and 100%. The interlaminar shear stress decreased as the proportion of jute fiber increased. Fractures appeared due to delamination between the surface-treated component and the main part of the HGJFRP composite bar. Tensile load-strain curves with 50% jute fiber exhibited linear behavior. With a jute fiber volume fraction of 70%, some plastic deformation occurred. A jute fiber mixing ratio of 100% resulted in a display of linear elastic brittle behavior from the fiber; however, when the surface of the fiber was coated with poly(vinyl acetate, following failure, the jute fiber exhibited partial load resistance. The tensile strength decreased as the jute fiber content increased; however, the tensile strength did not vary linearly with jute fiber content.

  1. Influence of different adhesive systems on the pull-out bond strength of glass fiber posts.

    da Silva, Luciana Mendonça; Andrade, Andréa Mello de; Machuca, Melissa Fernanda Garcia; da Silva, Paulo Maurício Batista; da Silva, Ricardo Virgolino C; Veronezi, Maria Cecília

    2008-01-01

    This in vitro study evaluated the tensile bond strength of glass fiber posts (Reforpost - Angelus-Brazil) cemented to root dentin with a resin cement (RelyX ARC - 3M/ESPE) associated with two different adhesive systems (Adper Single Bond - 3M/ESPE and Adper Scotchbond Multi Purpose (MP) Plus - 3M/ESPE), using the pull-out test. Twenty single-rooted human teeth with standardized root canals were randomly assigned to 2 groups (n=10): G1- etching with 37% phosphoric acid gel (3M/ESPE) + Adper Single Bond + #1 post (Reforpost - Angelus) + four #1 accessory posts (Reforpin - Angelus) + resin cement; G2- etching with 37% phosphoric acid gel + Adper Scotchbond MP Plus + #1 post + four #1 accessory posts + resin cement. The specimens were stored in distilled water at 37 degrees C for 7 days and submitted to the pull-out test in a universal testing machine (EMIC) at a crosshead speed of 0.5 mm/min. The mean values of bond strength (kgf) and standard deviation were: G1- 29.163 +/- 7.123; G2- 37.752 +/-13.054. Statistical analysis (Student's t-test; a=0.05 showed no statistically significant difference (pAdhesive bonding failures between resin cement and root canal dentin surface were observed in both groups, with non-polymerized resin cement in the apical portion of the post space when Single Bond was used (G1). The type of adhesive system employed on the fiber post cementation did not influence the pull-out bond strength.

  2. Influence of different adhesive systems on the pull-out bond strength of glass fiber posts

    Luciana Mendonça da Silva

    2008-06-01

    Full Text Available This in vitro study evaluated the tensile bond strength of glass fiber posts (Reforpost - Angelus-Brazil cemented to root dentin with a resin cement (RelyX ARC - 3M/ESPE associated with two different adhesive systems (Adper Single Bond - 3M/ESPE and Adper Scotchbond Multi Purpose (MP Plus - 3M/ESPE, using the pull-out test. Twenty single-rooted human teeth with standardized root canals were randomly assigned to 2 groups (n=10: G1- etching with 37% phosphoric acid gel (3M/ESPE + Adper Single Bond + #1 post (Reforpost - Angelus + four #1 accessory posts (Reforpin - Angelus + resin cement; G2- etching with 37% phosphoric acid gel + Adper Scotchbond MP Plus + #1 post + four #1 accessory posts + resin cement. The specimens were stored in distilled water at 37°C for 7 days and submitted to the pull-out test in a universal testing machine (EMIC at a crosshead speed of 0.5 mm/min. The mean values of bond strength (kgf and standard deviation were: G1- 29.163 ± 7.123; G2- 37.752 ±13.054. Statistical analysis (Student's t-test; a=0.05 showed no statistically significant difference (p<0.05 between the groups. Adhesive bonding failures between resin cement and root canal dentin surface were observed in both groups, with non-polymerized resin cement in the apical portion of the post space when Single Bond was used (G1. The type of adhesive system employed on the fiber post cementation did not influence the pull-out bond strength.

  3. Design of a robust thin-film interference filter for erbium-doped fiber amplifier gain equalization

    Verly, Pierre G.

    2002-06-01

    Gain-flattening filters (GFFs) are key wavelength division multiplexing components in fiber-optics telecommunications. Challenging issues in the design of thin-film GFFs were recently the subject of a contest organized at the 2001 Conference on Optical Interference Coatings. The interest and main difficulty of the proposed problem was to minimize the sensitivity of a GFF to simulated fabrication errors. A high-yield solution and its design philosophy are described. The approach used to control the filter robustness is explained and illustrated by numerical results.

  4. Mechanical characterization of SiC particulate & E-glass fiber reinforced Al 3003 hybrid metal matrix composites

    Narayana, K. S. Lakshmi; Shivanand, H. K.

    2018-04-01

    Metal matrix composites constitute a class of low cost high quality materials which offer high performance for various industrial applications. The orientation of this research is towards the study of mechanical properties of as cast silicon carbide (SiC) particulates and Short E-Glass fibers reinforced Aluminum matrix composites (AMCs). The Hybrid metal matrix composite is developed by reinforcing SiC particulates of 100 microns and short E-Glass fibers of 2-3 mm length with Al 3003 in different compositions. The vortex method of stir casting was employed, in which the reinforcements were introduced into the vortex created by the molten metal by means of mechanical stirrer. The mechanical properties of the prepared metal matrix composites were analyzed. From the studies it was noticed that an improvement in mechanical properties of the reinforced alloys compared to unreinforced alloys.

  5. Fabrication and characterization of chromium-doped nanophase separated yttria-alumina-silica glass-based optical fibers

    Dutta, Debjit; Dhar, Anirban; Das, Shyamal; Paul, Mukul C. [Fiber Optics and Photonics Division, CSIR-Central Glass and Ceramic Research Institute, Kolkata (India); Kir' yanov, Alexander V. [Centro de Investigaciones en Optica, Guanajuato (Mexico); Bysakh, Sandip [Electron Microscopic Section, Material Characterization Division, CSIR-Central Glass and Ceramic Research Institute, Kolkata (India)

    2015-08-15

    The basic material and optical properties of chromium-doped nanophase-separated yttria-alumina-silica (YAS) glass based optical preforms and fibers, fabricated through the modified chemical vapor deposition process in conjunction with solution doping technique under suitable thermal annealing conditions are reported. The size of the phase-separated particles within the core of the annealed preform is around 20-30 nm which is significantly reduced to around 5.0 nm in the drawn fiber. The absorption spectra of fibers drawn from the annealed and non-annealed preform samples revealed the presence of Cr{sup 4+}, Cr{sup 3+}, and Cr{sup 6+} specie. Numerically, extinction of absorption drops ∝3-3.5 times for the annealed sample as a result of nano-phase restructuration during annealing process. Intense broadband emission (within 500-800 nm) in case of the annealed preform sample is observed as compared to the non-annealed one and is associated with the presence of Cr{sup 3+} ions in nanostructured environment inside the YAS core glass. The final fibers show broadband emission ranging from 900 to 1400 nm under pumping at 1064 nm which is attributed mainly to the presence of Cr{sup 3+}/Cr{sup 4+} ions. The fabricated fibers seem to be a potential candidate for the development of fiber laser sources for the visible and near-infra ranges and for effective Q-switching units for ∝1-1.1 μm all-fiber ytterbium lasers. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. AMA- and RWE- Based Adaptive Kalman Filter for Denoising Fiber Optic Gyroscope Drift Signal.

    Yang, Gongliu; Liu, Yuanyuan; Li, Ming; Song, Shunguang

    2015-10-23

    An improved double-factor adaptive Kalman filter called AMA-RWE-DFAKF is proposed to denoise fiber optic gyroscope (FOG) drift signal in both static and dynamic conditions. The first factor is Kalman gain updated by random weighting estimation (RWE) of the covariance matrix of innovation sequence at any time to ensure the lowest noise level of output, but the inertia of KF response increases in dynamic condition. To decrease the inertia, the second factor is the covariance matrix of predicted state vector adjusted by RWE only when discontinuities are detected by adaptive moving average (AMA).The AMA-RWE-DFAKF is applied for denoising FOG static and dynamic signals, its performance is compared with conventional KF (CKF), RWE-based adaptive KF with gain correction (RWE-AKFG), AMA- and RWE- based dual mode adaptive KF (AMA-RWE-DMAKF). Results of Allan variance on static signal and root mean square error (RMSE) on dynamic signal show that this proposed algorithm outperforms all the considered methods in denoising FOG signal.

  7. Time-Dependent Deformation Modelling for a Chopped-Glass Fiber Composite for Automotive Durability Design Criteria; FINAL

    Ren, W

    2001-01-01

    Time-dependent deformation behavior of a polymeric composite with chopped-glass-fiber reinforcement was investigated for automotive applications, The material under stress was exposed to representative automobile service environments. Results show that environment has substantial effects on time-dependent deformation behavior of the material. The data were analyzed and experimentally-based models developed for the time-dependent deformation behavior as a basis for automotive structural durability design criteria

  8. Time-Dependent Deformation Modelling for a Chopped-Glass Fiber Composite for Automotive Durability Design Criteria

    Ren, W

    2001-08-24

    Time-dependent deformation behavior of a polymeric composite with chopped-glass-fiber reinforcement was investigated for automotive applications, The material under stress was exposed to representative automobile service environments. Results show that environment has substantial effects on time-dependent deformation behavior of the material. The data were analyzed and experimentally-based models developed for the time-dependent deformation behavior as a basis for automotive structural durability design criteria.

  9. Investigation on Stress-Rupture Behavior of a Chopped-Glass-Fiber Composite for Automotive Durability Design Criteria

    Ren, W

    2001-08-24

    Practical and inexpensive testing methods were developed to investigate stress-rupture properties of a polymeric composite with chopped glass fiber reinforcement for automotive applications. The material was tested in representative automotive environments to generate experimental data. The results indicate that environments have substantial effects on the stress-rupture behavior. The data were analyzed and developed into stress-rupture design criteria to address one of the durability aspects of the material for automotive structural applications.

  10. Investigation on Stress-Rupture Behavior of a Chopped-Glass-Fiber Composite for Automotive Durability Design Criteria; FINAL

    Ren, W

    2001-01-01

    Practical and inexpensive testing methods were developed to investigate stress-rupture properties of a polymeric composite with chopped glass fiber reinforcement for automotive applications. The material was tested in representative automotive environments to generate experimental data. The results indicate that environments have substantial effects on the stress-rupture behavior. The data were analyzed and developed into stress-rupture design criteria to address one of the durability aspects of the material for automotive structural applications

  11. Influence of Coating with Some Natural Based Materials on the Erosion Wear Behavior of Glass Fiber Reinforced Epoxy Resin

    Aseel Basim Abdul Hussein; Emad Saadi AL-Hassani; Reem Alaa Mohamed

    2015-01-01

    In the present study, composites were prepared by Hand lay-up molding. The composites constituents were epoxy resin as a matrix, 6% volume fractions of glass fibers (G.F) as reinforcement and 3%, 6% volume fractions of preparation natural material (Rice Husk Ash, Carrot Powder, and Sawdust) as filler. Studied the erosion wear behavior and coating by natural wastes (Rice Husk Ash) with epoxy resin after erosion. The results showed the non – reinforced epoxy have lower resistance erosion than n...

  12. Thermo-Mechanical Properties of Unsaturated Polyester Reinforced with SiliconCarbide Powder And with Chopped Glass Fiber

    Bushra Hosnie Musa

    2018-02-01

    Full Text Available The work studied the effectoffine silicon carbide (SiC powder with (0,3,5,7wt % on the thermal conductivity and mechanical properties of unsaturated polyester composite in the presence of a fixed amount of chopped glass fiber. The hand lay-up technique was employed to preparethe required samples. Results showed that tensile, impact strength and thermal conductivity increased with increasing the weight fraction of reinforced materials.

  13. Study on mechanical properties of fly ash impregnated glass fiber reinforced polymer composites using mixture design analysis

    Satheesh Raja, R.; Manisekar, K.; Manikandan, V.

    2014-01-01

    Highlights: • FRP with and without fly ash filler were prepared. • Mechanical properties of composites were analyzed. • Mixture Design Method was used to model the system. • Experimental and mathematical model results were compared. - Abstract: This paper describes the mechanical behavior of fly ash impregnated E-glass fiber reinforced polymer composite (GFRP). Initially the proportion of fiber and resin were optimized from the analysis of the mechanical properties of the GFRP. It is observed that the 30 wt% of E-glass in the GFRP without filler material yields better results. Then, based on the optimized value of resin content, the varying percentage of E-glass and fly ash was added to fabricate the hybrid composites. Results obtained in this study were mathematically evaluated using Mixture Design Method. Predictions show that 10 wt% addition of fly ash with fiber improves the mechanical properties of the composites. The fly ash impregnated GFRP yields significant improvement in mechanical strength compared to the GFRP without filler material. The surface morphologies of the fractured specimens were characterized using Scanning Electron Microscope (SEM). The chemical composition and surface morphology of the fly ash is analyzed by using Energy Dispersive Spectroscopy (EDS) and Scanning Electron Microscope

  14. Tribological and mechanical behaviors of polyamide 6/glass fiber composite filled with various solid lubricants.

    Li, Duxin; Xie, Ying; Li, Wenjuan; You, Yilan; Deng, Xin

    2013-01-01

    The effects of polytetrafluoroethylene (PTFE), graphite, ultrahigh molecular weight polyethylene (UHMWPE), and their compounds on mechanical and tribological properties of glass-fiber-reinforced polyamide 6 (PA6/GF) were studied. The polymeric materials were blended using twin-screw extruder and subsequently injection molded for test samples. Mechanical properties were investigated in terms of hardness, tensile strength, and impact strength. Friction and wear experiments were run under ambient conditions at a rotating speed of 200 rpm and load of 100 N. The morphologies of the worn surfaces were also observed with scanning electron microscope. The results showed that graphite could increase the tensile strength of PA6/GF-15 composite, but the material became soft. Graphite/UHMWPE complex solid lubricants were effective in increasing the already high impact strength of PA6/GF-15 composite. 5% PTFE gave the maximum reduction in the coefficient of friction. However, PTFE/UHMWPE complex solid lubricants were the best choice for improving both friction and wear behaviors due to the lower friction coefficient and mass wear rate. Moreover, the worn surface of PA6 composites revealed that adhesive wear, abrasive wear, and fatigue wear occurred in this study.

  15. The Effect of Thermooxidative Aging on the Durability of Glass Fiber-Reinforced Epoxy

    Amin Khajeh

    2015-01-01

    Full Text Available Thin-skinned organic matrix composites within aeronautical structures are subjected to thermooxidative aging during their service life, leading to reductions in their durability. In this paper, a durability evaluation of fiberglass epoxy prepreg is performed on the original composite thickness before and after 800 h isothermal aging at 82°C. The characterization of both aged and unaged composites comprised tensile tests, DMA, FTIR, weight loss measurements, SEM, and DSC. The tensile strength and modulus of the composites increased after being exposed to pronounced aging conditions, whereas a decrease was observed in the toughness. DMA results revealed that the glass transition temperature and rubbery state modulus increased as a result of the thermooxidative aging. FTIR spectroscopy demonstrated the formation of carbonyl compounds due to oxidation of the chemical structure of the resin. SEM observations indicated the existence of minor superficial cracking and poor fiber-matrix adhesion after aging. In addition, a minor mass change was observed from mass loss monitoring methods. The overall findings suggest that postcuring and physical aging enhanced the brittleness of the resin, leading to a significant decline in the useful structural life of the thin-skinned composite.

  16. Application of Glass Fiber Waste Polypropylene Aggregate in Lightweight Concrete – thermal properties

    Citek, D.; Rehacek, S.; Pavlik, Z.; Kolisko, J.; Dobias, D.; Pavlikova, M.

    2018-03-01

    Actual paper focus on thermal properties of a sustainable lightweight concrete incorporating high volume of waste polypropylene aggregate as partial substitution of natural aggregate. In presented experiments a glass fiber reinforced polypropylene (GFPP) which is a by-product of PP tubes production, partially substituted fine natural silica aggregate in 10, 20, 30, 40 and 50 mass %. Results were compared with a reference concrete mix without plastic waste in order to quantify the effect of GFPP use on concrete properties. Main material physical parameters were studied (bulk density, matrix density without air content, and particle size distribution). Especially a thermal transport and storage properties of GFPP were examined in dependence on compaction time. For the developed lightweight concrete, thermal properties were accessed using transient impulse technique, where the measurement was done in dependence on moisture content (from the fully water saturated state to dry state). It was found that the tested lightweight concrete should be prospective construction material possessing improved thermal insulation function and the reuse of waste plastics in concrete composition was beneficial both from the environmental and financial point of view.

  17. Preparation and characterization of glass fibers – polymers (epoxy bars (GFRP reinforced concrete for structural applications

    Alkjk Saeed

    2016-06-01

    Full Text Available The paper presents some of the results from a large experimental program undertaken at the Department of Civil Engineering of Damascus University. The project aims to study the ability to reinforce and strengthen the concrete by bars from Epoxy polymer reinforced with glass fibers (GFRP and compared with reinforce concrete by steel bars in terms of mechanical properties. Five diameters of GFRP bars, and steel bars (4mm, 6mm, 8mm, 10mm, 12mm tested on tensile strength tests. The test shown that GFRP bars need tensile strength more than steel bars. The concrete beams measuring (15cm wide × 15cm deep × and 70cm long reinforced by GFRP with 0.5 vol.% ratio, then the concrete beams reinforced by steel with 0.89 vol.% ratio. The concrete beams tested on deflection test. The test shown that beams which reinforced by GFRP has higher deflection resistance, than beams which reinforced by steel. Which give more advantage to reinforced concrete by GFRP.

  18. Double-Sided Terahertz Imaging of Multilayered Glass Fiber-Reinforced Polymer

    Przemyslaw Lopato

    2017-06-01

    Full Text Available Polymer matrix composites (PMC play important roles in modern industry. Increasing the number of such structures in aerospace, construction, and automotive applications enforces continuous monitoring of their condition. Nondestructive inspection of layered composite materials is much more complicated process than evaluation of homogenous, (mostly metallic structures. Several nondestructive methods are utilized in this case (ultrasonics, shearography, tap testing, acoustic emission, digital radiography, infrared imaging but none of them gives full description of evaluated structures. Thus, further development of NDT techniques should be studied. A pulsed terahertz method seems to be a good candidate for layered PMC inspection. It is based on picosecond electromagnetic pulses interacting with the evaluated structure. Differences of dielectric parameters enables detection of a particular layer in a layered material. In the case of multilayered structures, only layers close to surface can be detected. The response of deeper ones is averaged because of multiple reflections. In this paper a novel inspection procedure with a data processing algorithm is introduced. It is based on a double-sided measurement, acquired signal deconvolution, and data combining. In order to verify the application of the algorithm stress-subjected glass fiber-reinforced polymer (GFRP was evaluated. The obtained results enabled detection and detailed analysis of delaminations introduced by stress treatment and proved the applicability of the proposed algorithm.

  19. Tribological and Mechanical Behaviors of Polyamide 6/Glass Fiber Composite Filled with Various Solid Lubricants

    Duxin Li

    2013-01-01

    Full Text Available The effects of polytetrafluoroethylene (PTFE, graphite, ultrahigh molecular weight polyethylene (UHMWPE, and their compounds on mechanical and tribological properties of glass-fiber-reinforced polyamide 6 (PA6/GF were studied. The polymeric materials were blended using twin-screw extruder and subsequently injection molded for test samples. Mechanical properties were investigated in terms of hardness, tensile strength, and impact strength. Friction and wear experiments were run under ambient conditions at a rotating speed of 200 rpm and load of 100 N. The morphologies of the worn surfaces were also observed with scanning electron microscope. The results showed that graphite could increase the tensile strength of PA6/GF-15 composite, but the material became soft. Graphite/UHMWPE complex solid lubricants were effective in increasing the already high impact strength of PA6/GF-15 composite. 5% PTFE gave the maximum reduction in the coefficient of friction. However, PTFE/UHMWPE complex solid lubricants were the best choice for improving both friction and wear behaviors due to the lower friction coefficient and mass wear rate. Moreover, the worn surface of PA6 composites revealed that adhesive wear, abrasive wear, and fatigue wear occurred in this study.

  20. Response of fiber Bragg gratings bonded on a glass/epoxy laminate subjected to static loadings

    Mulle, Matthieu

    2015-04-22

    Fiber Bragg gratings (FBG) may be used to monitor strain over the surface of a structure as an alternative technology to conventional strain gauges. However, FBG bonding techniques have still not been established to yield satisfactory surface measurements. Here, two adhesives were investigated, one with low viscosity and the other with high viscosity for bonding FBGs on glass/epoxy sandwich skins. First, instrumented elementary specimens were tested under tension. FBG strain results were analyzed together with digital image correlation (DIC) measurements. The influence of the bonding layer on the measured strain and on the integrity of the sensor was investigated by considering different regions of interest. Next, an instrumented structural sandwich beam was tested under four-point bending. FBG rosettes were compared to conventional strain gauge rosettes. The high viscosity adhesive demonstrated behaviors that affected FBG accuracy. Brittleness of the bonding layer and poor interface adhesion were observed using DIC and X-ray tomography. By contrast, the low viscosity adhesive demonstrated satisfactory results. The FBG strain measurements appeared to be consistent with those of DIC. The accuracy is also adequate as the FBGs and the conventional strain gauges had similar results in three directions, under tension and under compression.

  1. Experimental Investigation on the Durability of Glass Fiber-Reinforced Polymer Composites Containing Nanocomposite

    Weiwen Li

    2013-01-01

    Full Text Available Nanoclay layers incorporated into polymer/clay nanocomposites can inhibit the harmful penetration of water and chemicals into the material, and thus the durability of glass fiber-reinforced polymer (GFRP composites should be enhanced by using polymer/clay nanocomposite as the matrix material. In this study, 1.5 wt% vinyl ester (VE/organoclay and 2 wt% epoxy (EP/organoclay nanocomposites were prepared by an in situ polymerization method. The dispersion states of clay in the nanocomposites were studied by performing XRD analysis. GFRP composites were then fabricated with the prepared 1.5 wt% VE/clay and 2.0 wt% EP/clay nanocomposites to investigate the effects of a nanocomposite matrix on the durability of GFRP composites. The durability of the two kinds of GFRP composites was characterized by monitoring tensile properties following degradation of GFRP specimens aged in water and alkaline solution at 60°C, and SEM was employed to study fracture behaviors of aged GFRP composites under tension. The results show that tensile properties of the two types of GFRP composites with and without clay degrade significantly with aging time. However, the GFRP composites with nanoclay show a lower degradation rate compared with those without nanoclay, supporting the aforementioned hypothesis. And the modification of EP/GFRP enhanced the durability more effectively.

  2. Shear Strengthening of RC Beams Using Sprayed Glass Fiber Reinforced Polymer

    Sayed Mohamad Soleimani

    2012-01-01

    Full Text Available The effectiveness of externally bonded sprayed glass fiber reinforced polymer (Sprayed GFRP in shear strengthening of RC beams under quasi-static loading is investigated. Different techniques were utilized to enhance the bond between concrete and Sprayed GFRP, involving the use of through bolts and nuts paired with concrete surface preparation through sandblasting and through the use of a pneumatic chisel prior to Sprayed GFRP application. It was found that roughening the concrete surface using a pneumatic chisel and using through bolts and nuts were the most effective techniques. Also, Sprayed GFRP applied on 3 sides (U-shaped was found to be more effective than 2-sided Sprayed GFRP in shear strengthening. Sprayed GFRP increased the shear load-carrying capacity and energy absorption capacities of RC beams. It was found that the load-carrying capacity of strengthened RC beams was related to an effective strain of applied Sprayed GFRP. This strain was related to Sprayed GFRP configuration and the technique used to enhance the concrete-FRP bond. Finally, an equation was proposed to calculate the contribution of Sprayed GFRP in the shear strength of an RC beam.

  3. Terahertz and Thermal Testing of Glass-Fiber Reinforced Composites with Impact Damages

    T. Chady

    2012-01-01

    Full Text Available The studies on glass-fiber reinforced composites, due to their growing popularity and high diversity of industrial applications, are becoming an increasingly popular branch of the nondestructive testing. Mentioned composites are used, among other applications, in wind turbine blades and are exposed to various kinds of damages. The equipment reliability requirements force the development of accurate methods of their health monitoring. In this paper we present the study of composite samples with impact damages, using three methods: terahertz time domain inspection, active thermography with convective excitation, and active thermography with microwave excitation. The results of discrete Fourier transform of obtained time sequences of signals will be presented as well as some image processing of resulting amplitude and phase images. Proposed experimental methods combined with harmonic analysis are efficient tool of defects detection and allowed to detect flaws in examined specimens. Reader may find it interesting that in spite of differences in nature of applied experimental methods, one technique of signal processing (harmonic analysis gave adequate and comparable results in each case.

  4. Ferromagnetic glass ceramics and glass fibers based on the composition of SiO{sub 2}-CaO-Al{sub 2}O{sub 3}-B{sub 2}O{sub 3}-Fe{sub 2}O{sub 3} glass system

    Liu, Jianan, E-mail: lja@qlu.edu.cn; Zhu, Chaofeng; Zhang, Meimei; Zhang, Yanfei; Yang, Xuena

    2017-03-15

    Ferromagnetic glass-ceramics and glass fibers were obtained by the melt-method from the glass system SiO{sub 2}-CaO-Al{sub 2}O{sub 3}-B{sub 2}O{sub 3}-Fe{sub 2}O{sub 3} without performing any nucleation and crystallization heat treatments. Glass-ceramics and glass fibers were characterized by x-ray diffraction, scanning and transmission electron microscopy, magnetic measurements, and thermal expansion instrument. The influence of alumina content on the spontaneous crystallization of magnetite, magnetism properties and thermal expansion performances in glass were investigated. We examined the crystallization behavior of the glasses and found that the spontaneous crystallization capacity of magnetite and magnetism properties in base glass increases with increasing the content of alumina. The ferromagnetic glass fibers containing magnetite nano-crystals are also obtained. - Highlights: • Magnetite nano-crystals are formed spontaneously in the investigated glass systems. • The crystallization behavior of the glasses with the alumina content is examined. • Ferromagnetic glass fibers containing magnetite nano-crystals are obtained.

  5. Preparation of a biomimetic composite scaffold from gelatin/collagen and bioactive glass fibers for bone tissue engineering

    Sharifi, Esmaeel; Azami, Mahmoud [Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Kajbafzadeh, Abdol-Mohammad [Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Pediatric Urology Research Center, Section of Tissue Engineering and Stem Cells Therapy, Department of Pediatric Urology, Children' s Hospital Medical Center, Tehran, Iran (IRI) (Iran, Islamic Republic of); Moztarzadeh, Fatollah [Department of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran (Iran, Islamic Republic of); Faridi-Majidi, Reza [Department of Medical Nanotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Shamousi, Atefeh; Karimi, Roya [Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Ai, Jafar, E-mail: jafar_ai@tums.ac.ir [Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Brain and Spinal Injury Research Center (BASIR), Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2016-02-01

    Bone tissue is a composite material made of organic and inorganic components. Bone tissue engineering requires scaffolds that mimic bone nature in chemical and mechanical properties. This study proposes a novel method for preparing composite scaffolds that uses sub-micron bioglass fibers as the organic phase and gelatin/collagen as the inorganic phase. The scaffolds were constructed by using freeze drying and electro spinning methods and their mechanical properties were enhanced by using genipin crosslinking agent. Electron microscopy micrographs showed that the structure of composite scaffolds were porous with pore diameters of approximately 70–200 μm, this was again confirmed by mercury porosimetery. These pores are suitable for osteoblast growth. The diameters of the fibers were approximately 150–450 nm. Structural analysis confirmed the formation of desirable phases of sub-micron bioglass fibers. Cellular biocompatibility tests illustrated that scaffolds containing copper ion in the bioglass structure had more cell growth and osteoblast attachment in comparison to copper-free scaffolds. - Highlights: • Fabrication of 45S5 sub-micron bioglass fiber using electrospinning method. • Production of copper doped submicron bioglass fibers on 45S5 bioglass base by electrospinning sol gel route method. • Incorporation of bioglass/Cu-bioglass sub-micron fibers into gelatin/collagen matrix to form biomimetic composite scaffold which were non-cytotoxic according to MTT assay. • Discovering that copper can decrease the glass transition temperatures and enhance osteoblast cell adhesion and viability.

  6. Preparation of a biomimetic composite scaffold from gelatin/collagen and bioactive glass fibers for bone tissue engineering

    Sharifi, Esmaeel; Azami, Mahmoud; Kajbafzadeh, Abdol-Mohammad; Moztarzadeh, Fatollah; Faridi-Majidi, Reza; Shamousi, Atefeh; Karimi, Roya; Ai, Jafar

    2016-01-01

    Bone tissue is a composite material made of organic and inorganic components. Bone tissue engineering requires scaffolds that mimic bone nature in chemical and mechanical properties. This study proposes a novel method for preparing composite scaffolds that uses sub-micron bioglass fibers as the organic phase and gelatin/collagen as the inorganic phase. The scaffolds were constructed by using freeze drying and electro spinning methods and their mechanical properties were enhanced by using genipin crosslinking agent. Electron microscopy micrographs showed that the structure of composite scaffolds were porous with pore diameters of approximately 70–200 μm, this was again confirmed by mercury porosimetery. These pores are suitable for osteoblast growth. The diameters of the fibers were approximately 150–450 nm. Structural analysis confirmed the formation of desirable phases of sub-micron bioglass fibers. Cellular biocompatibility tests illustrated that scaffolds containing copper ion in the bioglass structure had more cell growth and osteoblast attachment in comparison to copper-free scaffolds. - Highlights: • Fabrication of 45S5 sub-micron bioglass fiber using electrospinning method. • Production of copper doped submicron bioglass fibers on 45S5 bioglass base by electrospinning sol gel route method. • Incorporation of bioglass/Cu-bioglass sub-micron fibers into gelatin/collagen matrix to form biomimetic composite scaffold which were non-cytotoxic according to MTT assay. • Discovering that copper can decrease the glass transition temperatures and enhance osteoblast cell adhesion and viability.

  7. Pr{sup 3+}-doped GeS{sub {ital x}}-based glasses for fiber amplifiers at 1.3 {mu}m

    Simons, D.R.; Faber, A.J.; de Waal, H. [Glass Technology, Eindhoven University of Technology, P.O. Box 595, 5600 AN Eindhoven (Netherlands)

    1995-03-01

    The photoluminescence properties of Pr{sup 3+}-doped GeS{sub {ital x}}-based glasses are studied and compared with those of other sulfide and fluoride glasses. The possibility of highly pump-power-efficient fiber amplifiers based on these GeS{sub {ital x}}-containing glasses in the telecommunications window at 1.3 {mu}m is discussed.

  8. Passive mode locking at harmonics of the free spectral range of the intracavity filter in a fiber ring laser.

    Zhang, Shumin; Lu, Fuyun; Dong, Xinyong; Shum, Ping; Yang, Xiufeng; Zhou, Xiaoqun; Gong, Yandong; Lu, Chao

    2005-11-01

    We report the passive mode-locking at harmonics of the free spectral range (FSR) of the intracavity multi-channel filter in a fiber ring laser. The laser uses a sampled fiber Bragg grating (SFBG) with a free spectral range (FSR) of 0.8 nm, or 99 GHz at 1555 nm, and a length of highly nonlinear photonic crystal fiber with low and flat dispersion. Stable picosecond soliton pulse trains with twofold to sevenfold enhancement in the repetition rate, relative to the FSR of the SFBG, have been achieved. The passive mode-locking mechanism that is at play in this laser relies on a dissipative four-wave mixing process and switching of repetition rate is realized simply by adjustment of the intracavity polarization controllers.

  9. Determination of HEPA Filter Efficiency With Diocthyl Pthalate Aerosol

    Bunawas; Ruslanto, P O; Suhariyono, G

    1996-01-01

    Ultrafine aerosol filtration by HEPA (High Efficiency Particulate Air) filter has been determinated experimentally, based on the measurement of monodisperse Diocthyl Pthalate (DOP) aerosol concentration before and after passing the test filter. Using this technique, filter efficiency can be determined as a function of aerosol diameter with range from 0.017 to 0.747 um. The average efficiencies for Whatman -41 ; Whatman -42 and Whatman GF/A filters were 56.14 %; 95,74 %; and 99.65 % respectively. Gelman A Fiber Glass and Whatman membrane filter have fulfilled criterion as HEPA filter according to standard of IAEA, because of their minimum effiency of 99.90 %

  10. Wavelength-tunable thulium-doped fiber laser by employing a self-made Fabry-Perot filter

    Wang, Y. P.; Ju, Y. L.; Wu, C. T.; Liu, W.; Yang, C.

    2017-06-01

    In this demonstration, we proposed a novel wavelength-tunable thulium-doped fiber laser (TDFL) with a self-made Fabry-Perot (F-P) filter. When the F-P filter was not inserted, the maximum output power of 11.1 W was achieved when the pump power was 70.2 W. The corresponding optical-to-optical conversion efficiency was 15.8% and the slope efficiency was 22.1%. When the F-P filter was inserted, the output wavelength could be tuned from 1952.9 to 1934.9 nm with the change of cavity length of F-P filter which was fixed on a piezoelectric ceramic transducer (PZT) controlled by the voltage applied to it. The full width at half maximum (FWHM) was no more than 0.19 nm. Furthermore, the wavelength fluctuations of the tunable fiber laser were kept within  ±0.2 nm.

  11. Ho3+-doped AlF3-TeO2-based glass fibers for 2.1 µm laser applications

    Wang, S. B.; Jia, Z. X.; Yao, C. F.; Ohishi, Y.; Qin, G. S.; Qin, W. P.

    2017-05-01

    Ho3+-doped AlF3-TeO2-based glass fibers based on AlF3-BaF2-CaF2-YF3-SrF2-MgF2-TeO2 glasses are fabricated by using a rod-in-tube method. The glass rod including a core and a thick cladding layer is prepared by using a suction method, where the thick cladding layer is used to protect the core from the effect of surface crystallization during the fiber drawing. By inserting the glass rod into a glass tube, the glass fibers with relatively low loss (~2.3 dB m-1 @ 1560 nm) are prepared. By using a 38 cm long Ho3+-doped AlF3-TeO2-based glass fiber as the gain medium and a 1965 nm fiber laser as the pump source, 2065 nm lasing is obtained for a threshold pump power of ~220 mW. With further increasing the pump power to ~325 mW, the unsaturated output power of the 2065 nm laser is about 82 mW and the corresponding slope efficiency is up to 68.8%. The effects of the gain fiber length on the lasing threshold, the slope efficiency, and the operating wavelength are also investigated. Our experimental results show that Ho3+-doped AlF3-TeO2-based glass fibers are promising gain media for 2.1 µm laser applications.

  12. Contribution to the improved ultrasonic testing of glass fiber-reinforced polymers based on analytic modeling; Beitrag zur Verbesserung der Ultraschallpruefung glasfaserverstaerkter Polymere auf der Grundlage analytischer Modellierung

    Gripp, S.

    2001-04-01

    The non-destructive testing of acoustic anisotropic materials like fiber composites has been evaluated. Modelling enabled predictions about wave deflection, direction of wave propagation, and refractive angle of ultrasonic waves in these media. Thus, measurements could be carried out using unidirectional glass-fiber composites.

  13. The influence of glass fibers on elongational viscosity studied by means of optical coherence tomography and X-ray computed tomography

    Aigner, M.; Köpplmayr, T.; Lang, C.; Burzic, I.; Miethlinger, J.; Salaberger, D.; Buchsbaum, A.; Leitner, M.; Heise, B.; Schausberger, S. E.; Stifter, D.

    2014-01-01

    We report on the flow characteristics of glass-fiber-reinforced polymers in elongational rheometry. Unlike polymers with geometrically isotropic fillers, glass-fiber-reinforced polymers exhibit flow behavior and rheology that depend heavily on the orientation, the length distribution and the content of the fibers. One of the primary objectives of this study was to determine the effect of fiber orientation, concentration and distribution on the entrance pressure drop by means of optical coherence tomography (OCT), full-field optical coherence microscopy (FF-OCM), and X-ray computed tomography (X-CT). Both pressure drop and melt flow were analyzed using a special elongation die (Thermo Scientific X-Die [3]) for inline measurements. Samples with a variety of fiber volume fractions, fiber lengths and processing temperatures were measured

  14. The influence of glass fibers on elongational viscosity studied by means of optical coherence tomography and X-ray computed tomography

    Aigner, M.; Salaberger, D.; Buchsbaum, A.; Heise, B.; Schausberger, S. E.; Köpplmayr, T.; Lang, C.; Leitner, M.; Stifter, D.; Burzic, I.; Miethlinger, J.

    2014-05-01

    We report on the flow characteristics of glass-fiber-reinforced polymers in elongational rheometry. Unlike polymers with geometrically isotropic fillers, glass-fiber-reinforced polymers exhibit flow behavior and rheology that depend heavily on the orientation, the length distribution and the content of the fibers. One of the primary objectives of this study was to determine the effect of fiber orientation, concentration and distribution on the entrance pressure drop by means of optical coherence tomography (OCT), full-field optical coherence microscopy (FF-OCM), and X-ray computed tomography (X-CT). Both pressure drop and melt flow were analyzed using a special elongation die (Thermo Scientific X-Die [3]) for inline measurements. Samples with a variety of fiber volume fractions, fiber lengths and processing temperatures were measured.

  15. A single source microwave photonic filter using a novel single-mode fiber to multimode fiber coupling technique.

    Chang, John; Fok, Mable P; Meister, James; Prucnal, Paul R

    2013-03-11

    In this paper we present a fully tunable and reconfigurable single-laser multi-tap microwave photonic FIR filter that utilizes a special SM-to-MM combiner to sum the taps. The filter requires only a single laser source for all the taps and a passive component, a SM-to-MM combiner, for incoherent summing of signal. The SM-to-MM combiner does not produce optical interference during signal merging and is phase-insensitive. We experimentally demonstrate an eight-tap filter with both positive and negative programmable coefficients with excellent correspondence between predicted and measured values. The magnitude response shows a clean and accurate function across the entire bandwidth, and proves successful operation of the FIR filter using a SM-to-MM combiner.

  16. Influence of screw holes and gamma sterilization on properties of phosphate glass fiber-reinforced composite bone plates.

    Han, Na; Ahmed, Ifty; Parsons, Andrew J; Harper, Lee; Scotchford, Colin A; Scammell, Brigitte E; Rudd, Chris D

    2013-05-01

    Polymers prepared from polylactic acid (PLA) have found a multitude of uses as medical devices. For a material that degrades, the main advantage is that an implant would not necessitate a second surgical event for removal. In this study, fibers produced from a quaternary phosphate-based glass (PBG) in the system 50P2O5-40CaO-5Na2O-5Fe2O3 were used to reinforce PLA polymer. The purpose of this study was to assess the effect of screw holes in a range of PBG-reinforced PLA composites with varying fiber layup and volume fraction. The flexural properties obtained showed that the strength and modulus values increased with increasing fiber volume fraction; from 96 MPa to 320 MPa for strength and between 4 GPa and 24 GPa for modulus. Furthermore, utilizing a larger number of thinner unidirectional (UD) fiber prepreg layers provided a significant increase in mechanical properties, which was attributed to enhanced wet out and thus better fiber dispersion during production. The effect of gamma sterilization via flexural tests showed no statistically significant difference between the sterilized and nonsterilized samples, with the exception of the modulus values for samples with screw holes. Degradation profiles revealed that samples with screw holes degraded faster than those without screw holes due to an increased surface area for the plates with screw holes in PBS up to 30 days. Scanning electron microscope (SEM) analysis revealed fiber pullout before and after degradation. Compared with various fiber impregnation samples, with 25% volume fraction, 8 thinner unidirectional prepreg stacked samples had the shortest fiber pull-out lengths in comparison to the other samples investigated.

  17. Reinforcing effect of glass-fiber mesh on complete dentures in a test model with a simulated oral mucosa.

    Yu, Sang-Hui; Oh, Seunghan; Cho, Hye-Won; Bae, Ji-Myung

    2017-11-01

    Studies that evaluated the strength of complete dentures reinforced with glass-fiber mesh or metal mesh on a cast with a simulated oral mucosa are lacking. The purpose of this in vitro study was to compare the mechanical properties of maxillary complete dentures reinforced with glass-fiber mesh with those of metal mesh in a new test model, using a simulated oral mucosa. Complete dentures reinforced with 2 types of glass-fiber mesh, SES mesh (SES) and glass cloth (GC) and metal mesh (metal) were fabricated. Complete dentures without any reinforcement were prepared as a control (n=10). The complete dentures were located on a cast with a simulated oral mucosa, and a load was applied on the posterior artificial teeth bilaterally. The fracture load, elastic modulus, and toughness of a complete denture were measured using a universal testing machine at a crosshead speed of 5 mm/min. The fracture load and elastic modulus were analyzed using 1-way analysis of variance, and the toughness was analyzed with the Kruskal-Wallis test (α=.05). The Tukey multiple range test was used as a post hoc test. The fracture load and toughness of the SES group was significantly higher than that of the metal and control groups (P<.05) but not significantly different from that of the GC group. The elastic modulus of the metal group was significantly higher than that of the control group (P<.05), and no significant differences were observed in the SES and GC groups. Compared with the control group, the fracture load and toughness of the SES and GC groups were higher, while those of the metal group were not significantly different. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  18. Tunable single-polarization single-longitudinal-mode erbium-doped fiber ring laser employing a CMFBG filter and saturable absorber

    Feng, Suchun; Lu, Shaohua; Peng, Wanjing; Li, Qi; Feng, Ting; Jian, Shuisheng

    2013-04-01

    A tunable single-polarization single-longitudinal-mode (SLM) erbium-doped fiber ring laser is proposed and demonstrated. For the first time as we know, a chirped moiré fiber Bragg grating (CMFBG) filter with ultra-narrow transmission band and a uniform fiber Bragg grating (UFBG) are used to select the laser longitudinal mode. The stable SLM operation of the fiber laser is guaranteed by the combination of the CMFBG filter and 3 m unpumped erbium-doped fiber acting as a saturable absorber. The single polarization operation of the fiber laser is obtained by using an inline broadband polarizer. A tuning range of about 0.7 nm with about 0.1 nm step is achieved by stretching the uniform FBG.

  19. Optimization Of Fluoride Glass Fiber Drawing With Respect To Mechanical Strength

    Schneider, H. W.; Schoberth, A.; Staudt, A.; Gerndt, Ch.

    1987-08-01

    Heavy metal fluoride fibers have attracted considerable attention recently as lightguides for infrared optical devices. Besides the optical loss mechanical performance of the fiber is of major interest. At present fiber strength suffers from surface crystallization prior to or during fiber drawing. We developed an etching method for the preparation of preforms with clean surface. Drawing these preforms under optimized conditions in a dry atmosphere results in fibers with improved strength. So far, mean value of 400 N/mm2 tensile strength have been achieved. Maximum values of 800 N/mm2 measured on etched fibers indicate an even higher strength potential for the material itself.

  20. Tribological properties of solid lubricants filled glass fiber reinforced polyamide 6 composites

    Li, Du-Xin; You, Yi-Lan; Deng, Xin; Li, Wen-Juan; Xie, Ying

    2013-01-01

    Highlights: ► The tribological properties of GF/PA6 improved by the incorporation of PTFE. ► PTFE and UHMWPE exhibited a synergism effect on reducing friction coefficient. ► Solid lubricants enlarged the range of applied velocity for GF/PA6 composite. - Abstract: The main purpose of this paper is to further optimize the tribological properties of the glass fiber reinforced PA6 (GF/PA6,15/85 by weight) for high performance friction materials using single or combinative solid lubricants such as Polytetrafluroethylene (PTFE), ultra-high molecular weight polyethylene (UHMWPE) and the combination of both of them. Various polymer blends, where GF/PA6 acts as the polymer matrix and solid lubricants as the dispersed phase were prepared by injection molding. The tribological properties of these materials and the synergism as a result of the incorporation of both PTFE and UHMWPE were investigated. The results showed that, at a load of 40 N and a velocity of 200 rpm, PTFE was effective in improving the tribological capabilities of matrix material. On the contrary, UHMWPE was not conductive to maintain the structure integrity of GF/PA6 composite and harmful to the friction and wear properties. The combination of PTFE and UHMWPE showed synergism on further reducing the friction coefficient of the composites filled with either PTFE or UHMWPE only. Effects of load and velocity on tribological behavior were also discussed. To further understand the wear mechanism, the worn surfaces were examined by scanning electron microscopy

  1. Flexural strength using Steel Plate, Carbon Fiber Reinforced Polymer (CFRP) and Glass Fiber Reinforced Polymer (GFRP) on reinforced concrete beam in building technology

    Tarigan, Johannes; Patra, Fadel Muhammad; Sitorus, Torang

    2018-03-01

    Reinforced concrete structures are very commonly used in buildings because they are cheaper than the steel structures. But in reality, many concrete structures are damaged, so there are several ways to overcome this problem, by providing reinforcement with Fiber Reinforced Polymer (FRP) and reinforcement with steel plates. Each type of reinforcements has its advantages and disadvantages. In this study, researchers discuss the comparison between flexural strength of reinforced concrete beam using steel plates and Fiber Reinforced Polymer (FRP). In this case, the researchers use Carbon Fiber Reinforced Polymer (CFRP) and Glass Fiber Reinforced Polymer (GFRP) as external reinforcements. The dimension of the beams is 15 x 25 cm with the length of 320 cm. Based on the analytical results, the strength of the beam with CFRP is 1.991 times its initial, GFRP is 1.877 times while with the steel plate is 1.646 times. Based on test results, the strength of the beam with CFRP is 1.444 times its initial, GFRP is 1.333 times while the steel plate is 1.167 times. Based on these test results, the authors conclude that beam with CFRP is the best choice for external reinforcement in building technology than the others.

  2. Crash worthy capacity of a hybridized epoxy-glass fiber aluminum columnar tube using repeated axial resistive force

    Paruka, Perowansa [Jalan Politeknik, Kota Kinabalu (Malaysia); Siswanto, Waluyo Adi [Universiti Tun Hussein Onn Malaysia, Parit Raja (Malaysia); Maleque, Md Abdul [Universiti Islam Antarabangsa Malaysia, Kuala Lumpur (Malaysia); Shah, Mohd Kamal Mohd [Universiti Malaysia Sabah, Kota Kinabalu (Malaysia)

    2015-05-15

    A combination of aluminum columnar member with composite laminate to form a hybrid structure can be used as collapsible energy absorbers especially in automotive vehicular structures to protect occupants and cargo. A key advantage of aluminum member in composite is that it provides ductile and stable plastic collapse mechanisms with progressive deformation in a stable manner by increasing energy absorption during collision. This paper presents an experimental investigation on the influence of the number of hybrid epoxy glass layers in overwrap composite columnar tubes. Three columnar tube specimens were used and fabricated by hand lay-up method. Aluminum square hollow shape was combined with externally wrapped by using an isophthalic epoxy resin reinforced with glass fiber skin with an orientation angle of 0 .deg. /90 .deg. The aluminum columnar tube was used as reference material. Crushed hybrid-composite columnar tubes were prepared using one, two, and three layers to determine the crash worthy capacity. Quasi-static crush test was conducted using INSTRON machine with an axial loading. Results showed that crush force and the number of layers were related to the enhancement of energy absorption before the collapse of columnar tubes. The energy absorption properties of the crushed hybrid-composite columnar tubes improved significantly with the addition of layers in the overwrap. Microscopic analysis on the modes of epoxy-glass fiber laminate failure was conducted by using scanning electron microscopy.

  3. Crash worthy capacity of a hybridized epoxy-glass fiber aluminum columnar tube using repeated axial resistive force

    Paruka, Perowansa; Siswanto, Waluyo Adi; Maleque, Md Abdul; Shah, Mohd Kamal Mohd

    2015-01-01

    A combination of aluminum columnar member with composite laminate to form a hybrid structure can be used as collapsible energy absorbers especially in automotive vehicular structures to protect occupants and cargo. A key advantage of aluminum member in composite is that it provides ductile and stable plastic collapse mechanisms with progressive deformation in a stable manner by increasing energy absorption during collision. This paper presents an experimental investigation on the influence of the number of hybrid epoxy glass layers in overwrap composite columnar tubes. Three columnar tube specimens were used and fabricated by hand lay-up method. Aluminum square hollow shape was combined with externally wrapped by using an isophthalic epoxy resin reinforced with glass fiber skin with an orientation angle of 0 .deg. /90 .deg. The aluminum columnar tube was used as reference material. Crushed hybrid-composite columnar tubes were prepared using one, two, and three layers to determine the crash worthy capacity. Quasi-static crush test was conducted using INSTRON machine with an axial loading. Results showed that crush force and the number of layers were related to the enhancement of energy absorption before the collapse of columnar tubes. The energy absorption properties of the crushed hybrid-composite columnar tubes improved significantly with the addition of layers in the overwrap. Microscopic analysis on the modes of epoxy-glass fiber laminate failure was conducted by using scanning electron microscopy.

  4. Laser-induced nonlinear crystalline waveguide on glass fiber format and diode-pumped second harmonic generation

    Shi, Jindan; Feng, Xian

    2018-03-01

    We report a diode pumped self-frequency-doubled nonlinear crystalline waveguide on glass fiber. A ribbon fiber has been drawn on the glass composition of 50GeO2-25B2O3-25(La,Yb)2O3. Surface channel waveguides have been written on the surface of the ribbon fiber, using space-selective laser heating method with the assistance of a 244 nm CW UV laser. The Raman spectrum of the written area indicates that the waveguide is composed of structure-deformed nonlinear (La,Yb)BGeO5 crystal. The laser-induced surface wavy cracks have also been observed and the forming mechanism of the wavy cracks has been discussed. Efficient second harmonic generation has been observed from the laser-induced crystalline waveguide, using a 976 nm diode pump. 13 μW of 488 nm output has been observed from a 17 mm long waveguide with 26.0 mW of launched diode pump power, corresponding to a normalized conversion efficiency of 4.4%W-1.

  5. Bone plate composed of a ternary nano-hydroxyapatite/polyamide 66/glass fiber composite: biomechanical properties and biocompatibility.

    Qiao, Bo; Li, Jidong; Zhu, Qingmao; Guo, Shuquan; Qi, Xiaotong; Li, Weichao; Wu, Jun; Liu, Yang; Jiang, Dianming

    2014-01-01

    An ideal bone plate for internal fixation of bone fractures should have good biomechanical properties and biocompatibility. In this study, we prepared a new nondegradable bone plate composed of a ternary nano-hydroxyapatite/polyamide 66/glass fiber (n-HA/PA66/GF) composite. A breakage area on the n-HA/PA66/GF plate surface was characterized by scanning electron microscopy. Its mechanical properties were investigated using bone-plate constructs and biocompatibility was evaluated in vitro using bone marrow-derived mesenchymal stem cells. The results confirmed that adhesion between the n-HA/PA66 matrix and the glass fibers was strong, with only a few fibers pulled out at the site of breakage. Fractures fixed by the n-HA/PA66/GF plate showed lower stiffness and had satisfactory strength compared with rigid fixation using a titanium plate. Moreover, the results with regard to mesenchymal stem cell morphology, MTT assay, Alizarin Red S staining, enzyme-linked immunosorbent assay, and reverse transcription polymerase chain reaction for alkaline phosphatase and osteocalcin showed that the n-HA/PA66/GF composite was suitable for attachment and proliferation of mesenchymal stem cells, and did not have a negative influence on matrix mineralization or osteogenic differentiation of mesenchymal stem cells. These observations indicate that the n-HA/PA66/GF plate has good biomechanical properties and biocompatibility, and may be considered a new option for internal fixation in orthopedic surgery.

  6. Cobalt and organics removal effect using fiber filter/reverse osmosis combination process for LLRW from korean PWR NPP

    Park, S.M.; Yang, H.Y.; Song, M.J.

    2001-01-01

    Evaporation system for liquid radioactive waste process has been used in Korean PWR nuclear power plants. The system is the most desirable process for decontamination factor (DF) theoretically. However, during the operation of the system, various problems have been arising such as scaling, carry over, etc. Because these problems make DF low, advanced technologies for liquid radwaste process have been world widely developed instead of keeping evaporation system. The main goal of new technologies is ALARA, ease of operation, cost effectiveness and minimization of environmental effect. Korea Electric Power Corporation is currently developing a combined treatment process for liquid radwaste using Micro-filter, Ultra-filter, Reverse Osmosis (RO) membrane, etc for the purpose of partly enhancement of evaporator and of having an alternative liquid radwaste process system for new reactors. As a part of the above project, the feasibility study using the Rolled Fiber-Filter (RFF) and RO membrane has been carried out. This paper reports the results of lab-test from the combined process of the fiber filtration and RO membrane module for cobalt and organics removal. The study was especially focused on the boric acid permeation in the RO unit. Because boric acid occupies large volume of the final waste after evaporation process, the new technology such as RO process has to be studied on the boron process. (author)

  7. CHARACTERIZATION OF COMMERCIALLY AVAILABLE ALKALI RESISTANT GLASS FIBER FOR CONCRETE REINFORCEMENT AND CHEMICAL DURABILITY COMPARISON WITH SrO-Mn2O3-Fe2O3-MgO-ZrO2-SiO2 (SMFMZS SYSTEM GLASSES

    Göktuğ GÜNKAYA

    2012-12-01

    Full Text Available According to the relevant literature, the utilization of different kind of glass fibers in concrete introduces positive effect on the mechanical behavior, especially toughness. There are many glassfibers available to reinforce concretes. Glass fiber composition is so important because it may change the properties such as strength, elastic modulus and alkali resistance. Its most important property to be used in concrete is the alkali resistance. Some glasses of SrO–MgO–ZrO2–SiO2 (SMZS quaternary system, such as 26SrO, 20MgO, 14ZrO2, 40SiO2 (Zrn glass, have been found to be highly alkali resistant thanks to their high ZrO2 and MgO contents. Previous researches on these glasses with MnO and/or Fe2O3 partially replacing SrO have been made with the aim of improving the chemical resistance and decreasing the production cost.The main target of the present study, first of all, was to characterize commercially available alkali resistant glass fiber for concrete reinforcement and then to compare its alkali durability with those of the SrO-Mn2O3-Fe2O3-MgO-ZrO2-SiO2 (SMFMZS system glasses. For such purposes, XRF, Tg-DTA, alkali resistance tests and SEM analysis conducted with EDX were employed. According tothe alkali endurance test results it was revealed that some of the SMFMZS system glass powders are 10 times resistant to alkali environments than the commercial glass fibers used in this study.Therefore, they can be considered as alternative filling materials on the evolution of chemically resistant concrete structures.

  8. Active control of long-period fiber-grating-based filters made in erbium-doped optical fibers

    Slavík, Radan; Kulishov, M.

    2007-01-01

    Roč. 32, č. 7 (2007), s. 757-759 ISSN 0146-9592 R&D Projects: GA AV ČR(CZ) KJB200670601; GA ČR(CZ) GA102/07/0999 Institutional research plan: CEZ:AV0Z20670512 Keywords : optical fibre filters Subject RIV: BH - Optics , Masers, Lasers Impact factor: 3.711, year: 2007

  9. Influence of antimicrobial solutions in the decontamination and adhesion of glass-fiber posts to root canals

    HARAGUSHIKU, Gisele Aihara; BACK, Eduardo Donato Eing Engelke; TOMAZINHO, Paulo Henrique; BARATTO, Flares; FURUSE, Adilson Yoshio

    2015-01-01

    Objective This study evaluated the effect of root canal disinfectants on the elimination of bacteria from the root canals, as well as their effect on glass-fiber posts bond strength. Material and Methods Fifty-three endodontically treated root canals had post spaces of 11 mm in length prepared and contaminated with E. faecalis. For CFU/ml analysis, eight teeth were contaminated for 1 h or 30 days (n=4). Teeth were decontaminated with 5% NaOCl, 2% CHX, or distilled water. As control, no decontamination was conducted. After decontamination, sterile paper points were used to collect samples, and CFU/ml were counted. For push-out, three groups were evaluated (n=15): irrigation with 2.5% NaOCl, 2% CHX, or sterile distilled water. A bonding agent was applied to root canal dentin, and a glass-fiber post was cemented with a dual-cured cement. After 24 h, 1-mm-thick slices of the middle portion of root canals were obtained and submitted to the push-out evaluation. Three specimens of each group were evaluated in scanning electron microscopy (SEM). Data were analyzed with one-way ANOVA and Dunnett’s T3 test (α=0.05). Results The number of CFU/ml increased from 1 h to 30 days of contamination in control and sterile distilled water groups. Decontamination with NaOCl was effective only when teeth were contaminated for 1 h. CHX was effective at both contamination times. NaOCl did not influence the bond strength (p>0.05). Higher values were observed with CHX (pcontaminated root canals both in reducing the bacterial contamination and in improving the glass-fiber post bonding. PMID:26398518

  10. Influence of antimicrobial solutions in the decontamination and adhesion of glass-fiber posts to root canals

    Gisele Aihara HARAGUSHIKU

    2015-08-01

    Full Text Available AbstractObjective This study evaluated the effect of root canal disinfectants on the elimination of bacteria from the root canals, as well as their effect on glass-fiber posts bond strength.Material and Methods Fifty-three endodontically treated root canals had post spaces of 11 mm in length prepared and contaminated with E. faecalis. For CFU/ml analysis, eight teeth were contaminated for 1 h or 30 days (n=4. Teeth were decontaminated with 5% NaOCl, 2% CHX, or distilled water. As control, no decontamination was conducted. After decontamination, sterile paper points were used to collect samples, and CFU/ml were counted. For push-out, three groups were evaluated (n=15: irrigation with 2.5% NaOCl, 2% CHX, or sterile distilled water. A bonding agent was applied to root canal dentin, and a glass-fiber post was cemented with a dual-cured cement. After 24 h, 1-mm-thick slices of the middle portion of root canals were obtained and submitted to the push-out evaluation. Three specimens of each group were evaluated in scanning electron microscopy (SEM. Data were analyzed with one-way ANOVA and Dunnett’s T3 test (α=0.05.Results The number of CFU/ml increased from 1 h to 30 days of contamination in control and sterile distilled water groups. Decontamination with NaOCl was effective only when teeth were contaminated for 1 h. CHX was effective at both contamination times. NaOCl did not influence the bond strength (p>0.05. Higher values were observed with CHX (p<0.05. SEM showed formation of resin tags in all groups.Conclusion CHX showed better results for the irrigation of contaminated root canals both in reducing the bacterial contamination and in improving the glass-fiber post bonding.

  11. Properties and structure of high erbium doped phosphate glass for short optical fibers amplifiers

    Seneschal, Karine; Smektala, Frederic; Bureau, Bruno; Floch, Marie Le; Jiang Shibin; Luo, Tao; Lucas, Jacques; Peyghambarian, Nasser

    2005-01-01

    New phosphate glasses have been developed in order to incorporate high rare-earth ions concentrations. These glasses present a great chemical stability and a high optical quality. The phosphate glass network is open, very flexible, with a linkage of the tetrahedrons very disordered and contains a larger number of non-bridging oxygens (66%). The great stability and resistance against crystallization associated with the possibility to incorporate high doping concentration of rare-earth ions in these phosphate glasses make them very good candidates for the realization of ultra short single mode amplifiers with a high gain at 1.55 μm

  12. Estimation of Relative Permittivity of Printed Circuit Board with Fiber Glass Epoxy as Dielectric for UHF Applications

    Ronal D. Montoya-Montoya

    2013-11-01

    Full Text Available This paper presents the results of measuring relative permittivity of fiber glass printed circuit board (PCB’s, using a rectangular resonant cavity. The relative permittivity is presented as function of frequency. To obtain resonant frequencies, the return loss was measured using a network analyzer. Relative permittivity was calculated by finding frequencies of resonant cavity modes. The results are presented in a frequency span of 1 to 3.5GHz. It was clearly shown the nonlinear behavior of the relative permittivity for the dielectric laminate evaluated, even what happens respect to the frequency of the resonant modes below and above to frequency of 2 GHz.

  13. Anisotropy and compression/tension asymmetry of PP containing soft and hard particles and short glass fibers

    A. M. Hartl

    2015-07-01

    Full Text Available Polypropylene (PP composites are used in a wide range of structural applications. Except for fiber reinforced PP, most PP particle composites are commonly considered to be isotropic or at least quasi-isotropic. In this paper, however, the anisotropy of several PP composites containing soft (rubber and hard (talc particles and glass fibers is characterized in detail in terms of the material microstructure as well as the resulting mechanical properties in monotonic tensile and compressive experiments. The microstructural investigations showed that all composites displayed a certain surface-core layer structure of distinctly different orientation patterns and with a higher degree of orientation in the surface layer. Also in mechanical testing an anisotropic behavior was observed with the degree of anisotropy being more pronounced in tension than compression. Moreover, the compression/tension asymmetry also strongly depends on filler type and orientation.

  14. High-pass filtering and dynamic gain regulation enhance vertical bursts transmission along the mossy fiber pathway of cerebellum

    Jonathan Mapelli

    2010-05-01

    Full Text Available Signal elaboration in the cerebellum mossy fiber input pathway presents controversial aspects, especially concerning gain regulation and the spot-like (rather than beam-like appearance of granular-to-molecular layer transmission. By using voltage-sensitive dye (VSD imaging in rat cerebellar slices (Mapelli et al., 2010, we found that mossy fiber bursts optimally excited the granular layer above ~50 Hz and the overlaying molecular layer above ~100 Hz, thus generating a cascade of high-pass filters. NMDA receptors enhanced transmission in the granular, while GABA-A receptors depressed transmission in both the granular and molecular layer. Burst transmission gain was controlled through a dynamic frequency-dependent involvement of these receptors. Moreover, while high-frequency transmission was enhanced along vertical lines connecting the granular to molecular layer, no high-frequency enhancement was observed along the parallel fiber axis in the molecular layer. This was probably due to the stronger effect of Purkinje cell GABA-A receptor-mediated inhibition occurring along the parallel fibers than along the granule cell axon ascending branch. The consequent amplification of burst responses along vertical transmission lines could explain the spot-like activation of Purkinje cells observed following punctuate stimulation in vivo .

  15. Preparation and properties of hexagonal boron nitride fibers used as high temperature membrane filter

    Hou, Xinmei, E-mail: houxinmei@ustb.edu.cn; Yu, Ziyou; Li, Yang; Chou, Kuo-Chih

    2014-01-01

    Graphical abstract: - Highlights: • h-BN fibers were successfully fabricated using H{sub 3}BO{sub 3} and C{sub 3}H{sub 6}N{sub 6} as raw materials. • The obtained BN fibers were polycrystalline and uniform in morphology. • It exhibited good oxidation resistance and low thermal expansion coefficient. - Abstract: Hexagonal boron nitride fibers were synthesized via polymeric precursor method using boric acid (H{sub 3}BO{sub 3}) and melamine (C{sub 3}H{sub 6}N{sub 6}) as raw materials. The precursor fibers were synthesized by water bath and BN fibers were prepared from the precursor at 1873 K for 3 h in flowing nitrogen atmosphere. The crystalline phase and microstructures of BN fibers were examined by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy and high resolution electron microscopy. The results showed that h-BN fibers with uniform morphology were successfully fabricated. The well-synthesized BN fibers were polycrystalline with 0.4–1.5 μm in diameter and 200–500 μm in length. The as-prepared samples exhibited good oxidation resistance and low thermal expansion coefficient at high temperature.

  16. A SESAM passively mode-locked fiber laser with a long cavity including a band pass filter

    Song, Rui; Chen, Hong-Wei; Chen, Sheng-Ping; Hou, Jing; Lu, Qi-Sheng

    2011-01-01

    A semiconductor saturable absorber mirror (SESAM) passively mode-locked fiber laser with a long cavity length over 700 m is demonstrated. A band pass filter is inserted into the laser cavity to stabilize the lasing wavelength. Some interesting phenomena are observed and discussed. The central wavelength, repetition rate, average power and single pulse energy of the laser are 1064 nm, 281.5 kHz, 11 mW and 39 nJ, respectively. The laser operates stably without Q-switching instabilities, which greatly reduces the damage opportunities of the SESAM

  17. UV-Assisted 3D Printing of Glass and Carbon Fiber-Reinforced Dual-Cure Polymer Composites.

    Invernizzi, Marta; Natale, Gabriele; Levi, Marinella; Turri, Stefano; Griffini, Gianmarco

    2016-07-16

    Glass (GFR) and carbon fiber-reinforced (CFR) dual-cure polymer composites fabricated by UV-assisted three-dimensional (UV-3D) printing are presented. The resin material combines an acrylic-based photocurable resin with a low temperature (140 °C) thermally-curable resin system based on bisphenol A diglycidyl ether as base component, an aliphatic anhydride (hexahydro-4-methylphthalic anhydride) as hardener and (2,4,6,-tris(dimethylaminomethyl)phenol) as catalyst. A thorough rheological characterization of these formulations allowed us to define their 3D printability window. UV-3D printed macrostructures were successfully demonstrated, giving a clear indication of their potential use in real-life structural applications. Differential scanning calorimetry and dynamic mechanical analysis highlighted the good thermal stability and mechanical properties of the printed parts. In addition, uniaxial tensile tests were used to assess the fiber reinforcing effect on the UV-3D printed objects. Finally, an initial study was conducted on the use of a sizing treatment on carbon fibers to improve the fiber/matrix interfacial adhesion, giving preliminary indications on the potential of this approach to improve the mechanical properties of the 3D printed CFR components.

  18. UV-Assisted 3D Printing of Glass and Carbon Fiber-Reinforced Dual-Cure Polymer Composites

    Marta Invernizzi

    2016-07-01

    Full Text Available Glass (GFR and carbon fiber-reinforced (CFR dual-cure polymer composites fabricated by UV-assisted three-dimensional (UV-3D printing are presented. The resin material combines an acrylic-based photocurable resin with a low temperature (140 °C thermally-curable resin system based on bisphenol A diglycidyl ether as base component, an aliphatic anhydride (hexahydro-4-methylphthalic anhydride as hardener and (2,4,6,-tris(dimethylaminomethylphenol as catalyst. A thorough rheological characterization of these formulations allowed us to define their 3D printability window. UV-3D printed macrostructures were successfully demonstrated, giving a clear indication of their potential use in real-life structural applications. Differential scanning calorimetry and dynamic mechanical analysis highlighted the good thermal stability and mechanical properties of the printed parts. In addition, uniaxial tensile tests were used to assess the fiber reinforcing effect on the UV-3D printed objects. Finally, an initial study was conducted on the use of a sizing treatment on carbon fibers to improve the fiber/matrix interfacial adhesion, giving preliminary indications on the potential of this approach to improve the mechanical properties of the 3D printed CFR components.

  19. Retrofit of hollow concrete masonry infilled steel frames using glass fiber reinforced plastic laminates

    Hakam, Zeyad Hamed-Ramzy

    2000-11-01

    This study focuses on the retrofit of hollow concrete masonry infilled steel frames subjected to in-plane lateral loads using glass fiber reinforced plastic (GFRP) laminates that are epoxy-bonded to the exterior faces of the infill walls. An extensive experimental investigation using one-third scale modeling was conducted and consisted of two phases. In the first phase, 64 assemblages, half of which were retrofitted, were tested under various combined in-plane loading conditions similar to those which different regions of a typical infill wall are subjected to. In the second phase, one bare and four masonry-infilled steel frames representative of a typical single-story, single-bay panel were tested under diagonal loading to study the overall behavior and the infill-frame interaction. The relative infill-to-frame stiffness was varied as a test parameter by using two different steel frame sections. The laminates altered the failure modes of the masonry assemblages and reduced the variability and anisotropic nature of the masonry. For the prisms which failed due to shear and/or mortar joint slip, significant strength increases were observed. For those exhibiting compression failure modes, a marginal increase in strength resulted. Retrofitting the infilled frames resulted in an average increase in initial stiffness of two-fold compared to the unretrofitted infilled frames, and seemed independent of the relative infill-to-frame stiffness. However, the increase in the load-carrying capacity of the retrofitted frames compared to the unretrofitted counterparts was higher for those with the larger relative infill-to-frame stiffness parameter. Unlike the unretrofitted infill walls, the retrofitted panels demonstrated almost identical failure modes that were characterized as "strictly comer crushing" in the vicinity of the loaded comers whereas no signs of distress were evident throughout the remainder of the infill. The laminates also maintained the structural integrity of

  20. Ytterbium‐doped distributed spectral filtering photonic crystal fibers for use at wavelengths above 1100 nm

    Petersen, Sidsel Rübner; Alkeskjold, Thomas Tanggaard; Lægsgaard, Jesper

    to avoid parasitic lasing due to Amplified Spontaneous Emission (ASE) build‐up. Nonlinear effects, such as stimulated Raman scattering, stimulated Brillouin scattering and four‐wave mixing, set the upper limit for achievable powers in fiber amplifiers. To increase the nonlinear threshold, Large......Rare‐earth doped high‐power fiber lasers and amplifiers have attracted a lot of attention, due to the advantages of the fiber amplification scheme. Compared to conventional optically pumped bulk lasers, heat is dissipated much more effectively in fiber lasers, having a large surface......‐to‐active volume ratio. Thereby, a stable beam with nearly diffraction‐limited quality can be achieved. The fibers are often cladding‐pumped with a number of low‐brightness semiconductor laser diodes, in which way a low‐cost pump of several kilowatts can be achieved [1]. However, the frequencies, which can...

  1. In Situ Cleanable Alternative HEPA Filter Media

    Adamson, D. J.; Terry, M. T.

    2002-01-01

    The Westinghouse Savannah River Company, located at the Savannah River Site in Aiken, South Carolina, is currently testing two types of filter media for possible deployment as in situ regenerable/cleanable High Efficiency Particulate Air (HEPA) filters. The filters are being investigated to replace conventional, disposable, glass-fiber, HEPA filters that require frequent removal, replacement, and disposal. This is not only costly and subjects site personnel to radiation exposure, but adds to the ever-growing waste disposal problem. The types of filter media being tested, as part of a National Energy Technology Laboratory procurement, are sintered nickel metal and ceramic monolith membrane. These media were subjected to a hostile environment to simulate conditions that challenge the high-level waste tank ventilation systems. The environment promoted rapid filter plugging to maximize the number of filter loading/cleaning cycles that would occur in a specified period of time. The filters were challenged using nonradioactive simulated high-level waste materials and atmospheric dust; materials that cause filter pluggage in the field. The filters are cleaned in situ using an aqueous solution. The study found that both filter media were insensitive to high humidity or moisture conditions and were easily cleaned in situ. The filters regenerated to approximately clean filter status even after numerous plugging and in situ cleaning cycles. Air Techniques International is conducting particle retention testing on the filter media at the Oak Ridge Filter Test Facility. The filters are challenged using 0.3-mm di-octyl phthalate particles. Both the ceramic and sintered media have a particle retention efficiency > 99.97%. The sintered metal and ceramic filters not only can be cleaned in situ, but also hold great potential as a long life alternative to conventional HEPA filters. The Defense Nuclear Facility Safety Board Technical Report, ''HEPA Filters Used in the Department of

  2. Improvement of the mode II interface fracture toughness of glass fiber reinforced plastics/aluminum laminates through vapor grown carbon fiber interleaves.

    Ning, Huiming; Li, Yuan; Hu, Ning; Cao, Yanping; Yan, Cheng; Azuma, Takesi; Peng, Xianghe; Wu, Liangke; Li, Jinhua; Li, Leilei

    2014-06-01

    The effects of acid treatment, vapor grown carbon fiber (VGCF) interlayer and the angle, i.e., 0° and 90°, between the rolling stripes of an aluminum (Al) plate and the fiber direction of glass fiber reinforced plastics (GFRP) on the mode II interlaminar mechanical properties of GFRP/Al laminates were investigated. The experimental results of an end notched flexure test demonstrate that the acid treatment and the proper addition of VGCF can effectively improve the critical load and mode II fracture toughness of GFRP/Al laminates. The specimens with acid treatment and 10 g m -2 VGCF addition possess the highest mode II fracture toughness, i.e., 269% and 385% increases in the 0° and 90° specimens, respectively compared to those corresponding pristine ones. Due to the induced anisotropy by the rolling stripes on the aluminum plate, the 90° specimens possess 15.3%-73.6% higher mode II fracture toughness compared to the 0° specimens. The improvement mechanisms were explored by the observation of crack propagation path and fracture surface with optical, laser scanning and scanning electron microscopies. Moreover, finite element analyses were carried out based on the cohesive zone model to verify the experimental fracture toughness and to predict the interface shear strength between the aluminum plates and GFRP laminates.

  3. Apparatus for Removing Remaining Adhesives of Filter

    Kang, Il Sik; Kim, Tae Kuk; Hong, Dae Seok; Ji, Young Yong; Ryu, Woo Seog

    2010-01-01

    A Large amount of ventilation filter was used at radiation areas not only in nuclear power plants but also in nuclear facilities. These spent ventilation filters are generated as radioactive waste and composed of a steel frame, glass fiber media and aluminum separator. When treated, the spent filter is separated into filter media for air purification and frame. After separation, while the filter media is collected using steel drum for reducing internal exposure, the filter frame is treated further to remove adhesives for recycling the frame as many as possible in order to reduce waste and cost and improve working conditions. Usually, the adhesives are separated from the filter frame manually. As a result, a lot of time and labor is required. So, the objective of this study is to develop a motor-driven apparatus for removing adhesives efficiently

  4. [Influence of retainer design on fixation strength of resin-bonded glass fiber reinforced composite fixed cantilever dentures].

    Petrikas, O A; Voroshilin, Iu G; Petrikas, I V

    2013-01-01

    Fiber-reinforced composite (FRC) fixed partial dentures (FPD) have become an accepted part of the restorative dentist's armamentarium. The aim of this study was to evaluate in vitro the influence of retainer design on the strength of two-unit cantilever resin-bonded glass FRC-FPDs. Four retainer designs were tested: a dual wing, a dual wing + horizontal groove, a dual wing + occlusal rest and a step-box. Of each design on 7 human mandibular molars, FRC-FPDs of a premolar size were produced. The FRC framework was made of resin Revolution (Kerr) impregnated glass fibers (GlasSpan, GlasSpan) and veneered with hybrid resin composite (Charisma, Kulzer). Revolution (Kerr) was used as resin luting cement. FRC-FPDs were loaded to failure in a universal testing machine. T (Student's)-test was used to evaluate the data. The four designs were analyzed with finite element analysis (FEA) to reveal the stress distribution within the tooth/restoration complex. Significantly lower fracture strengths were observed with inlay-retained FPDs (step-box: 172±11 N) compared to wing-retained FPDs (poptimal design for replacement of a single premolar by means of a two-unit cantilever FRC-FPDs.

  5. Monotonic and cyclic responses of impact polypropylene and continuous glass fiber-reinforced impact polypropylene composites at different strain rates

    Yudhanto, Arief

    2016-03-08

    Impact copolymer polypropylene (IPP), a blend of isotactic polypropylene and ethylene-propylene rubber, and its continuous glass fiber composite form (glass fiber-reinforced impact polypropylene, GFIPP) are promising materials for impact-prone automotive structures. However, basic mechanical properties and corresponding damage of IPP and GFIPP at different rates, which are of keen interest in the material development stage and numerical tool validation, have not been reported. Here, we applied monotonic and cyclic tensile loads to IPP and GFIPP at different strain rates (0.001/s, 0.01/s and 0.1/s) to study the mechanical properties, failure modes and the damage parameters. We used monotonic and cyclic tests to obtain mechanical properties and define damage parameters, respectively. We also used scanning electron microscopy (SEM) images to visualize the failure mode. We found that IPP generally exhibits brittle fracture (with relatively low failure strain of 2.69-3.74%) and viscoelastic-viscoplastic behavior. GFIPP [90]8 is generally insensitive to strain rate due to localized damage initiation mostly in the matrix phase leading to catastrophic transverse failure. In contrast, GFIPP [±45]s is sensitive to the strain rate as indicated by the change in shear modulus, shear strength and failure mode.

  6. An Investigation on Tensile Properties of Glass Fiber/Aluminium Laminates

    M. Sadighi

    2009-12-01

    Full Text Available The idea of combining low weight and good mechanical properties has led to efforts to develop a new light fiber/metal laminate (FML in the last decade. FMLs are hybrid composites consisting of alternating thin layers of metal sheets and fiber-reinforced epoxy prepregs. In this study, the effect of fiber orientation on tensile properties of this material is investigated both analytically and experimentally. An analytical constitutive model based on classical lamination theory by using Kirchhoff-Love assumption, which incorporates the elastic-plastic behavior of the aluminium alloy was applied. Test results show that fiber sheet, with zero angle in laminates, improve the tensile strength. The composite layers with different fiber orientation change specimens' mode of fracture. Good agreement is obtained between the model predictions and experimental results.

  7. Thermal energy harvesting for large-scale applications using MWCNT-grafted glass fibers and polycarbonate-MWCNT nanocomposites

    Tzounis, L., E-mail: ltzounis@physics.auth.gr [Leibniz-Institut für Polymerforschung Dresden e.V., IPF, Hohe Str. 6, D-01069 Dresden (Germany); Technische Universität Dresden, Helmholtzstraße 10, 01069 Dresden (Germany); Laboratory for Thin Films-Nanosystems and Nanometrolo (Greece); Liebscher, M.; Stamm, M. [Leibniz-Institut für Polymerforschung Dresden e.V., IPF, Hohe Str. 6, D-01069 Dresden, Germany and Technische Universität Dresden, Helmholtzstraße 10, 01069 Dresden (Germany); Mäder, E.; Pötschke, P. [Leibniz-Institut für Polymerforschung Dresden e.V., IPF, Hohe Str. 6, D-01069 Dresden (Germany); Logothetidis, S., E-mail: logot@auth.gr [Laboratory for Thin Films-Nanosystems and Nanometrology (LTFN), Physics Department, Aristotle University of Thessaloniki, GR-54124 Thessaloniki (Greece)

    2015-02-17

    The thermoelectric properties of multi-wall carbon nanotube (MWCNT) -grafted glass fiber yarns (GF-CNT) and their epoxy model composites, as well as of polymer nanocomposites consisting of a polycarbonate (PC) matrix filled with differently functionalized MWCNTs have been examined. The GF-CNT hierarchical multi-scale structures were prepared by dip coating glass fiber yarns in a solution of carbonyl chloride modified MWCNTs; MWCNT-COCl (at a concentration of 0.5 mg/ml) under Ar atmosphere. The resulting GF-CNT exhibited high electrical conductivity (σ = 2.1×10{sup 3} S/m) due to the dense MWCNT deposited networks. The fiber surface morphology was investigated by scanning electron microscopy (SEM). The GF-CNT showed Seebeck coefficient (S); S = 16.8 μV/K, and power factor (P.F); P.F = 0.59 μW/mK−2. The high electrical conductivity of the GF-CNT is a key parameter for an optimum thermoelectric performance, since it can facilitate the flow of the thermally induced charge carriers upon being exposed to a temperature gradient. Polycarbonate/MWCNT nanocomposites were prepared by small-scale melt-mixing process using a microcompounder. Unfunctionalized, carboxyl (-COOH) and hydroxyl (-OH) modified MWCNTs were incorporated in PC at a constant amount of 2.5 wt.%, concentration above the electrical percolation threshold. The amount of MWCNTs was kept low to understand the fundamental aspects of their physical properties and their correlation to the composite morphology, as revealed by transmission electron microscopy (TEM). It was found that different functional groups can affect the thermoelectric performance and the conductivity of the nanocomposites. Namely, the highest Seebeck coefficient (S) was found for the composite containing carboxyl functionalized MWCNTs (11.3 μV/K), due to the highest oxygen content of MWCNTs proven by X-Ray Photoelectron spectroscopy (XPS). It is believed that MWCNT-grafted glass fibers as reinforcements in composite structural

  8. Thermal energy harvesting for large-scale applications using MWCNT-grafted glass fibers and polycarbonate-MWCNT nanocomposites

    Tzounis, L.; Liebscher, M.; Stamm, M.; Mäder, E.; Pötschke, P.; Logothetidis, S.

    2015-01-01

    The thermoelectric properties of multi-wall carbon nanotube (MWCNT) -grafted glass fiber yarns (GF-CNT) and their epoxy model composites, as well as of polymer nanocomposites consisting of a polycarbonate (PC) matrix filled with differently functionalized MWCNTs have been examined. The GF-CNT hierarchical multi-scale structures were prepared by dip coating glass fiber yarns in a solution of carbonyl chloride modified MWCNTs; MWCNT-COCl (at a concentration of 0.5 mg/ml) under Ar atmosphere. The resulting GF-CNT exhibited high electrical conductivity (σ = 2.1×10 3 S/m) due to the dense MWCNT deposited networks. The fiber surface morphology was investigated by scanning electron microscopy (SEM). The GF-CNT showed Seebeck coefficient (S); S = 16.8 μV/K, and power factor (P.F); P.F = 0.59 μW/mK−2. The high electrical conductivity of the GF-CNT is a key parameter for an optimum thermoelectric performance, since it can facilitate the flow of the thermally induced charge carriers upon being exposed to a temperature gradient. Polycarbonate/MWCNT nanocomposites were prepared by small-scale melt-mixing process using a microcompounder. Unfunctionalized, carboxyl (-COOH) and hydroxyl (-OH) modified MWCNTs were incorporated in PC at a constant amount of 2.5 wt.%, concentration above the electrical percolation threshold. The amount of MWCNTs was kept low to understand the fundamental aspects of their physical properties and their correlation to the composite morphology, as revealed by transmission electron microscopy (TEM). It was found that different functional groups can affect the thermoelectric performance and the conductivity of the nanocomposites. Namely, the highest Seebeck coefficient (S) was found for the composite containing carboxyl functionalized MWCNTs (11.3 μV/K), due to the highest oxygen content of MWCNTs proven by X-Ray Photoelectron spectroscopy (XPS). It is believed that MWCNT-grafted glass fibers as reinforcements in composite structural materials

  9. Influence of Hygrothermal Aging on Poisson’s Ratio of Thin Injection-Molded Short Glass Fiber-Reinforced PA6

    Thomas Illing; Heinrich Gotzig; Marcus Schoßig; Christian Bierögel; Wolfgang Grellmann

    2016-01-01

    The hygrothermal aging of short glass fiber-reinforced polyamide 6 materials (PA6 GF) represents a major problem, especially in thin-walled components, such as in the automotive sector. In this study, therefore, the thickness and the glass fiber content of PA6 GF materials were varied and the materials were exposed to hygrothermal aging. The temperature and relative humidity were selected in the range from −40 °C up to 85 °C, and from 10% up to 85% relative humidity (RH). In the dry-as-molded...

  10. 1887 nm lasing in Tm3+-doped TeO2-BaF2-Y2O3 glass microstructured fibers

    Wang, Shunbin; Yao, Chuanfei; Jia, Zhixu; Qin, Guanshi; Qin, Weiping

    2017-04-01

    In this paper, we demonstrate ∼2 μm lasing in Tm3+-doped fluorotellurite microstructured fibers. The Tm3+-doped fibers are based on TeO2-BaF2-Y2O3 glasses and fabricated by using a rod-in-tube method. Under the pump of a 1570 nm Er3+-doped fiber laser, lasing at 1887 nm is obtained in a ∼42.5 cm long Tm3+-doped fiber with a threshold pump power of 94 mW. As the pump power increases to 780 mW, the obtained maximum unsaturated power reaches up to ∼408 mW with a slop efficiency of ∼58.1%. This result indicates that the Tm3+-doped fluorotellurite fibers are promising gain media for ∼2 μm fiber lasers.

  11. Influence of mold temperature associated with glass fiber on the mechanical and thermal properties of a (PA6/GF/MMT) nanocomposite

    Damiani, Renato Adriano

    2017-01-01

    This work describes the second of a series of studies of the effects of injection molding conditions on the mechanical and thermal properties of Polyamide 6/Glass Fiber/Montmorillonite (PA6/GF/MMT) composites and was motivated by the lack of information about how the processing variables influence on the properties of three-phase composites containing fiber glass. By this time, the effects of the injection molding temperature associated with the fiber glass percentage on the mechanical and thermal properties of the composite are investigated. Some samples were processed, following a statistical experimental factorial planning, varying the mold temperature and the fiber glass percentage and maintaining 5 wt % of the MMT. The samples were submitted to tensile and flexural tests, XRD, SEM and DSC. The studies showed that an increase in the mold temperature and the fiber percentage improves the maximum tensile and flexural stresses. The increased mold temperature slows the cooling rate, which, over time, decreases the degree of crystallinity. However, there is an increase in the intercalation of the polymeric chains and the nanoclay lamellae, and the structure forms with fewer defects. (author)

  12. Influence of mold temperature associated with glass fiber on the mechanical and thermal properties of a (PA6/GF/MMT) nanocomposite

    Damiani, Renato Adriano, E-mail: eng.damiani@hotmail.com [Universidade do Extremo Sul Catarinense (UNESC), Criciuma, SC (Brazil). Programa de Pos-Graduacao em Ciencias e Engenharia de Materiais; Duarte, Glaucea Warmeling; Riella, Humberto Gracher, E-mail: gwduarte@gmail.com, E-mail: huberto.riella@ufsc.br [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Programa de Pos-Graduacao em Engenharia Quimica; Silva, Luciano Luiz; Mello, Josiane Maria Muneron de; Fiori, Marcio Antonio; Batiston, Eduardo Roberto, E-mail: marciofiori@gmail.com, E-mail: lucianols@unochapeco.edu.br, E-mail: josimello@unochapeco.edu.br, E-mail: erbatiston@unochapeco.edu.br [Universidade Comunitaria da Regiao de Chapeco (UNOCHAPECO), Chapeco, SC (Brazil)

    2017-01-15

    This work describes the second of a series of studies of the effects of injection molding conditions on the mechanical and thermal properties of Polyamide 6/Glass Fiber/Montmorillonite (PA6/GF/MMT) composites and was motivated by the lack of information about how the processing variables influence on the properties of three-phase composites containing fiber glass. By this time, the effects of the injection molding temperature associated with the fiber glass percentage on the mechanical and thermal properties of the composite are investigated. Some samples were processed, following a statistical experimental factorial planning, varying the mold temperature and the fiber glass percentage and maintaining 5 wt % of the MMT. The samples were submitted to tensile and flexural tests, XRD, SEM and DSC. The studies showed that an increase in the mold temperature and the fiber percentage improves the maximum tensile and flexural stresses. The increased mold temperature slows the cooling rate, which, over time, decreases the degree of crystallinity. However, there is an increase in the intercalation of the polymeric chains and the nanoclay lamellae, and the structure forms with fewer defects. (author)

  13. Effects of sea water environment on glass fiber reinforced plastic materials used for marine civil engineering constructions

    Garcia-Espinel, J.D.; Castro-Fresno, D.; Parbole Gayo, P.; Ballester-Muñoz, F.

    2015-01-01

    Highlights: • Seawater environment over composite material that are suitable for civil applications. • Seawater intake is linked to tensile and flexural strength degradation in GFC. • Fatigue performance of glass composites is similar in seawater environment than in air. - Abstract: Glass fiber composites (GFRP) are common in civil engineering projects, but not in marine structures. One reason is that seawater effects degrade GFRP composites mechanical properties and interlaminar shear strength (ILSS). Here, influence of seawater environment is studied to determine the best composite materials for marine civil engineer applications, studying the influence of several factors in their mechanical properties. This is to determine safety factors to use in the design of structural calculations for marine applications. Glass/epoxy composites are the safest materials to use in marine civil structures as mechanical properties degradation becomes stabilized after moisture saturation level. UV and water cyclic analysis must be done to determine affection to transversal strength. Only vinylester GFRP has problems with biodegradation. GFRP fatigue performance is not influenced by seawater environment

  14. Response of fiber Bragg gratings bonded on a glass/epoxy laminate subjected to static loadings

    Mulle, Matthieu; Moussawi, Ali; Lubineau, Gilles; Durand, Samuel; Falandry, Didier; Olivier, Philippe

    2015-01-01

    measurements. Here, two adhesives were investigated, one with low viscosity and the other with high viscosity for bonding FBGs on glass/epoxy sandwich skins. First, instrumented elementary specimens were tested under tension. FBG strain results were analyzed

  15. Narrow line-width Tm3+ doped double-clad silica fiber laser based on in-line cascade biconical tapers filter

    Tian, Y; Zhao, J Q; Wang, W; Wang, Y Z; Gao, W

    2010-01-01

    Narrow line-width 793 nm laser diode cladding pumped Tm 3+ doped double cladding silica fiber laser with in-line four concatenated tapers filter was reported for the first time to our knowledge. These cascade tapers located 3.6 cm from the output end of the fiber laser was fabricated by heating and stretching method. The taper's transmitted power response as a function of wavelength was described by using local mode coupling theory and successive tapers filter model. The wavelength filter function of the in-line cascade tapers in a linear cavity fiber laser was demonstrated, and the experimental result agreed with these theories. The maximum output laser power was 736 mW, corresponding to single peak of laser spectrum with narrow line-width of ∼ 60 pm

  16. Effects of the cooling rate on the shear behavior of continuous glass fiber/impact polypropylene composites (GF-IPP)

    Wafai, Husam

    2016-09-20

    Fiber-reinforced composites with improved dissipation of energy during impact loading have recently been developed based on a polypropylene copolymer commonly called impact polypropylene (IPP). Composites made of IPP reinforced with glass fibers (GF) are particularly attractive to the automotive industry due to their low cost and good impact resistance. In such composites, the cooling rate varies depending on processing techniques and manufacturing choices. Here, we study the effects of the cooling rate of GF-IPP composites on shear behavior, which is critical in impact applications, using [±45]s monotonic and cyclic (load/unload) tensile specimens. The specimens were manufactured under a wide range of cooling rates (3 °C/min, 22 °C/min, 500–1000 °C/min). Mainly dominated by the properties of the matrix, the global shear behavior of GF-IPP composites differed considerably with respect to the cooling rate. However, the performance of the fiber-matrix interface (chemically modified) appeared to be unaffected by the range of cooling rates used in this study. We found that the cooling rate has a minor effect on the rate of damage accumulation, while it strongly modifies the shear-activated rate-dependant viscoelastic behavior. © 2016 Elsevier Ltd

  17. Fiber Bragg grating based notch filter for bit-rate-transparent NRZ to PRZ format conversion with two-degree-of-freedom optimization

    Cao, Hui; Zuo, Jun; Xiong, Bangyun; Cheng, Jianqun; Shu, Xuewen; Shen, Fangcheng; Liu, Xin; Atai, Javid

    2015-01-01

    We propose a novel notch-filtering scheme for bit-rate transparent all-optical NRZ-to-PRZ format conversion. The scheme is based on a two-degree-of-freedom optimally designed fiber Bragg grating. It is shown that a notch filter optimized for any specific operating bit rate can be used to realize high-Q-factor format conversion over a wide bit rate range without requiring any tuning. (paper)

  18. Estimation of Wear Behavior of Polyphenylene Sulphide Composites Reinforced with Glass/Carbon Fibers, Graphite and Polytetrafluoroethylene, by Pin-on-disc Test

    M.A.C. Besnea

    2015-03-01

    Full Text Available Wear behavior of polyphenylene sulphide composites was investigated according to load and test speed. Two types of materials were studied: first, with 40 wt% glass fiber, and second, with 10 wt% carbon fiber, 10 wt% graphite and 10 wt%. Tribological tests were performed on the universal tribometer UMT-2, using a pin-on-disc device. The friction coefficient and wear rate for the composites were analyzed. As a result of experimental tests, it was established that polymer composite with polyphenylene sulphide matrix, carbon fibers, graphite and polytetrafluorethylene exhibit good wear behavior under operating conditions.

  19. Fabrication of highly nonlinear germano-silicate glass optical fiber incorporated with PbTe semiconductor quantum dots using atomization doping process and its optical nonlinearity.

    Ju, Seongmin; Watekar, Pramod R; Han, Won-Taek

    2011-01-31

    Germano-silicate glass optical fiber incorporated with PbTe semiconductor quantum dots (SQDs) in the core was fabricated by using the atomization process in modified chemical vapor deposition (MCVD) process. The absorption bands attributed to PbTe semiconductor quantum dots in the fiber core were found to appear at around 687 nm and 1055 nm. The nonlinear refractive index measured by the long-period fiber grating (LPG) pair method upon pumping with laser diode at 976.4 nm was estimated to be ~1.5 × 10(-16) m2/W.

  20. The effects of embedded piezoelectric fiber composite sensors on the structural integrity of glass-fiber–epoxy composite laminate

    Konka, Hari P; Wahab, M A; Lian, K

    2012-01-01

    Piezoelectric fiber composite sensors (PFCSs) made from micro-sized lead zirconate titanate (PZT) fibers have many advantages over the traditional bulk PZT sensors for embedded sensor applications. PFCSs as embedded sensors will be an ideal choice to continuously monitor the stress/strain levels and health conditions of composite structures. PFCSs are highly flexible, easily embeddable, have high compatibility with composite structures, and also provides manufacturing flexibility. This research is focused on examining the effects of embedding PFCS sensors (macro-fiber composite (MFC) and piezoelectric fiber composite (PFC)) on the structural integrity of glass-fiber–epoxy composite laminates. The strengths of composite materials with embedded PFCSs and conventional PZT sensors were compared, and the advantages of PFCS sensors over PZTs were demonstrated. Initially a numerical simulation study is performed to understand the local stress/strain field near the embedded sensor region inside a composite specimen. High stress concentration regions were observed near the embedded sensor corner edge. Using PFCS leads to a reduction of 56% in longitudinal stress concentration and 38% in transverse stress concentration, when compared to using the conventional PZTs as embedded sensors. In-plane tensile, in-plane tension–tension fatigue, and short beam strength tests are performed to evaluate the strengths/behavior of the composite specimens containing embedded PFCS. From the tensile test it is observed that embedding PFCS and PZT sensors in the composite structures leads to a reduction in ultimate strength by 3 and 6% respectively. From the fatigue test results it is concluded that both embedded PFCS and PZT sensors do not have a significant effect on the fatigue behavior of the composite specimens. From the short beam strength test it is found that embedding PFCS and PZT sensors leads to a reduction in shear strength by 7 and 15% respectively. Overall the pure PZT

  1. Hybrid carbon-glass fiber/toughened epoxy thick composites subject to drop-weight and ballistic impacts

    Sevkat, Ercan

    The goals of this study are to investigate the low velocity and ballistic impact response of thick-section hybrid fiber composites at room temperature. Plain-woven S2-Glass and IM7 Graphite fabrics are chosen as fiber materials reinforcing the SC-79 epoxy. Four different types of composites consisting of alternating layers of glass and graphite woven fabric sheets are considered. Tensile tests are conducted using 98 KN (22 kip) MTS testing machine equipped with environmental chamber. Low-velocity impact tests are conducted using an Instron-Dynatup 8250 impact test machine equipped with an environmental chamber. Ballistic impact tests are performed using helium pressured high-speed gas-gun. Tensile tests results were used to define the material behavior of the hybrid and non-hybrid composites in Finite Element modeling. The low velocity and ballistic impact tests showed that hybrid composites performance was somewhere between non-hybrid woven composites. Using woven glass fabrics as outer skin improved the impact performance of woven graphite composite. However hybrid composites are prone to delamination especially between dissimilar layers. The ballistic limit velocity V50 hybrid composites were higher that of woven graphite composite and lower than that of woven glass composite. Both destructive cross-sectional micrographs and nondestructive ultrasonic techniques are used to evaluate the damage created by impact. The Finite Element code LS-DYNA is chosen to perform numerical simulations of low velocity and ballistic impact on thick-section hybrid composites. The damage progression in these composites shows anisotropic nonlinearity. The material model to describe this behavior is not available in LS-DYNA material library. Initially, linear orthotropic material with damage (Chan-Chan Model) is employed to simulate some of the experimental results. Then, user-defined material subroutine is incorporated into LS-DYNA to simulate the nonlinear behavior. The

  2. Developments of DPF systems with mesh laminated structures. Performances of DPF systems which consist of the metal-mesh laminated filter combustion with the alumina-fiber mesh, and the combustion device of trapped diesel particles; Mesh taso kozo no DPF no kaihatsu. Kinzokusen to arumina sen`i mesh ni yoru fukugo filter to filter heiyo heater ni yoru DPF no seino

    Kojima, T; Tange, A; Matsuda, K [NHK Spring Co. Ltd., Yokohama (Japan)

    1997-10-01

    For the purpose of continuous run without any maintenance, new DPF (diesel particulate filter)systems laminated by both metal-wire mesh and alumina-fiber mesh alternately, are under the developments. The perfect combustion of trapped diesel particulate can be achieved by a couple of the resistance heating devices inserted into the filter. 5 refs., 7 figs., 3 tabs.

  3. Effect of nanoparticles and nanofibers on Mode I fracture toughness of fiber glass reinforced polymeric matrix composites

    Kelkar, Ajit D.; Mohan, Ram; Bolick, Ronnie; Shendokar, Sachin

    2010-01-01

    Graphical abstract: Use of alumina nanoparticles and TEOS electrospun nanofibers at the interfaces of glass fiber plies to develop delamination resistant epoxy polymeric composites and compare their Mode I fracture toughness characteristics. - Abstract: In the recent past, the research involving the fabrication and processing of reinforced polymer nanocomposites has increased significantly. These new materials are enabling in the discovery, development and incorporation of improved nanocomposite materials with effective manufacturing methodologies for several defense and industrial applications. These materials eventually will allow the full utilization of nanocomposites in not only reinforcing applications but also in multifunctional applications where sensing and the unique optical, thermal, electrical and magnetic properties of nanoparticles can be combined with mechanical reinforcement to offer the greatest opportunities for significant advances in material design and function. This paper presents two methods and material systems for processing and integration of the nanomaterial constituents, namely: (a) dispersing alumina nanoparticles using high energy mixing (using ultrasonication, high shear mixing and pulverization) and (b) electrospinning technique to manufacture nanofibers. These reinforced polymer nanocomposites and the processing methodologies are likely to provide effective means of improving the interlaminar properties of woven fiber glass composites compared to the traditional methods such as stitching and Z-pinning. The electrospinning technology relies on the creation of nanofibers with improved molecular orientation with reduced concentration of fiber imperfections and crystal defects. Electrospinning process utilizes surface tension effects created by electrostatic forces acting on liquid droplets, creating numerous nanofibers. These nanofibers thus have potential to serve as through-the-thickness reinforcing agents in woven composites. While

  4. Recovery of phosphonate surface contaminants from glass using a simple vacuum extractor with a solid-phase microextraction fiber

    Groenewold, Gary S.; Scott, Jill R.; Rae, Catherine

    2011-01-01

    Graphical abstract: Highlights: → A field vacuum extractor (FVE) nondestructively samples surface-adsorbed organics. → The FVE creates a modest vacuum over the surface, volatilizing surface organics. → A solid phase microextraction fiber (SPME) collects volatilized organics. → The SPME is easily analyzed using GC/MS. → The FVE enables collection chemical signatures from hard-to-sample surfaces. - Abstract: Recovery of chemical contaminants from fixed surfaces for analysis can be challenging, particularly if it is not possible to acquire a solid sample to be taken to the laboratory. A simple device is described that collects semi-volatile organic compounds from fixed surfaces by creating an enclosed volume over the surface, then generating a modest vacuum. A solid-phase microextraction (SPME) fiber is then inserted into the evacuated volume where it functions to sorb volatilized organic contaminants. The device is based on a syringe modified with a seal that is used to create the vacuum, with a perforable plunger through which the SPME fiber is inserted. The reduced pressure speeds partitioning of the semi-volatile compounds into the gas phase and reduces the boundary layer around the SPME fiber, which enables a fraction of the volatilized organics to partition into the SPME fiber. After sample collection, the SPME fiber is analyzed using conventional gas chromatography/mass spectrometry. The methodology has been used to collect organophosphorus compounds from glass surfaces, to provide a simple test for the functionality of the devices. Thirty minute sampling times (ΔT vac ) resulted in fractional recovery efficiencies that ranged from 10 -3 to >10 -2 , and in absolute terms, collection of low nanograms was demonstrated. Fractional recovery values were positively correlated to the vapor pressure of the compounds being sampled. Fractional recovery also increased with increasing ΔT vac and displayed a roughly logarithmic profile, indicating that an

  5. Tribological Behavior of TiC/a-C : H-Coated and Uncoated Steels Sliding Against Phenol-Formaldehyde Composite Reinforced with PTFE and Glass Fibers

    Shen, J.T.; Pei, Y.T.; Hosson, J.Th.M. De

    2013-01-01

    Tribological experiments on phenol-formaldehyde composite reinforced with polytetrafluoroethylene (PTFE) and glass fibers were performed against 100Cr6 steel and TiC/a-C:H thin film-coated 100Cr6 steel. In both cases, the coefficient of friction increases with increasing sliding distance until a

  6. Dynamic mechanical analysis and high strain-rate energy absorption characteristics of vertically aligned carbon nanotube reinforced woven fiber-glass composites

    The dynamic mechanical behavior and energy absorption characteristics of nano-enhanced functionally graded composites, consisting of 3 layers of vertically aligned carbon nanotube (VACNT) forests grown on woven fiber-glass (FG) layer and embedded within 10 layers of woven FG, with polyester (PE) and...

  7. The restoration of a maxillary central incisor fracture with the original crown fragment using a glass fiber-reinforced post: a clinical report.

    Durkan, Rukiye Kaplan; Ozel, M Birol; Celik, Davut; Bağiş, Bora

    2008-12-01

    This report describes an esthetic, conservative, and economical alternative restoration technique for a fractured central incisor using the patient's own tooth crown piece and a bondable reinforcement glass fiber. Although the long-term durability of this adhesive post core restoration remains unknown, it remains successful after 1 year.

  8. Extractable substances (anionic surfactants) from membrane filters induce morphological changes in the green alga Scenedesmus obliquus (Chlorophyceae)

    Lürling, M.; Beekman, W.

    2002-01-01

    The effect of filtration of medium through different kinds of filters (glass fiber, mixed esters of cellulose and nitrocellulose) on the morphology in the green alga Scenedesmus obliquus was examined. Several compounds potentially released from membrane filters were further investigated, and among

  9. Diagnostics of glass fiber reinforced polymers and comparative analysis of their fabrication techniques with the use of acoustic emission

    Bashkov, O. V.; Bryansky, A. A.; Panin, S. V.; Zaikov, V. I.

    2016-11-01

    Strength properties of the glass fiber reinforced polymers (GFRP) fabricated by vacuum and vacuum autoclave molding techniques were analyzed. Measurements of porosity of the GFRP parts manufactured by various molding techniques were conducted with the help of optical microscopy. On the basis of experimental data obtained by means of acoustic emission hardware/software setup, the technique for running diagnostics and forecasting the bearing capacity of polymeric composite materials based on the result of three-point bending tests has been developed. The operation principle of the technique is underlined by the evaluation of the power function index change which takes place on the dependence of the total acoustic emission counts versus the loading stress.

  10. Planar ultra thin glass seals with optical fiber interface for monitoring tamper attacks on security eminent components

    Thiel, M.; Flachenecker, G.; Schade, W.; Gorecki, C.; Thoma, A.; Rathje, R.

    2017-11-01

    Optical seals consisting of waveguide Bragg grating sensor structures in ultra thin glass transparencies have been developed to cover security relevant objects for detection of unauthorized access. For generation of optical signature in the seals, femtosecond laser pulses were used. The optical seals were connected with an optical fiber to enable external read out of the seal. Different attack scenarios for getting undetected access to the object, covered by the seal, were proven and evaluated. The results presented here, verify a very high level of security. An unauthorized detaching and subsequent replacement by original or copy of the seals for tampering would be accompanied with a very high technological effort, posing a substantial barrier towards an attacker. Additionally, environmental influences like temperature effects have a strong but reproducible influence on signature, which in context of a temperature reference database increases the level of security significantly.

  11. Modification of glass fibers to improve reinforcement: a plasma polymerization technique

    Çökeliler, D.; Erkut, S.; Zemek, Josef; Biederman, H.; Mutlu, M.

    2007-01-01

    Roč. 23, č. 3 (2007), s. 335-342 ISSN 0109-5641 Institutional research plan: CEZ:AV0Z10100521 Keywords : plasma polymerization * glos-discharge * E-glass fibros * ethylendiamine * 2-hydroxyethyl methacrystalate * triethyleneglycoldimethylether * fibre-reinforced composite ( FRC) Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.990, year: 2007

  12. Preparation and characterization of VB metal group glass for optical fiber communication devices

    Aranha, N.; Barbosa, L.C.; Garrido, F.M.S.; Alves, O.L.

    1990-01-01

    In this work was prepared the glass of composition Nb 2 O 5 (25.04%) - PbO (23.91%) - P 2 O 5 (34.25%) - K 2 O (16.80%) using a RF induction furnace at temperature of 1400 C for two hours under ambient atmosphere. The obtained glass are annealed at 300 C. The samples (powder and thin plates) was characterized by X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR), UV-Vis spectroscopy and by determination of the thermal coefficient of expansion (dilatometry). Results shown the formation of a very homogeneous glass with a thermal coefficient of expansion (α) of 22.7.10 -6 C -1 . The ir bands suggest the formation of a phosphate glass with a good transmission in the region of 2.0-2.9 microns (5000-3400 cm -1 ). The transmission spectrum shows that the material is transparent in the region of 400-1000 nm with a cut-off at near 350nm. (author) [pt

  13. Influence of different catilever extensions and glass or polyamaramid reinforcement fibers on fracture strength of implant-supported temporary

    Paola Colán Guzmán

    2008-04-01

    Full Text Available In long-term oral rehabilitation treatments, resistance of provisional crowns is a very important factor, especially in cases of an extensive edentulous distal space. The aim of this laboratorial study was to evaluate an acrylic resin cantilever-type prosthesis regarding the flexural strength of its in-balance portion as a function of its extension variation and reinforcement by two types of fibers (glass and polyaramid, considering that literature is not conclusive on this subject. Each specimen was composed by 3 total crowns at its mesial portion, each one attached to an implant component (abutment, while the distal portion (cantilever had two crowns. Each specimen was constructed by injecting acrylic resin into a two-part silicone matrix placed on a metallic base. In each specimen, the crowns were fabricated with either acrylic resin (control group or acrylic resin reinforced by glass (Fibrante, Angelus or polyaramide (Kevlar 49, Du Pont fibers. Compression load was applied on the cantilever, in a point located 7, 14 or 21 mm from the distal surface of the nearest crown with abutment, to simulate different extensions. The specimen was fixed on the metallic base and the force was applied until fracture in a universal test machine. Each one of the 9 sub-groups was composed by 10 specimens. Flexural strength means (in kgf for the distances of 7, 14 and 21 mm were, respectively, 28.07, 8.27 and 6.39 for control group, 31.89, 9.18 and 5.16 for Kevlar 49 and 30.90, 9.31 and 6.86 for Fibrante. Data analysis ANOVA showed statistically significant difference (p<0.05 only regarding cantilever extension. Tukey's test detected significantly higher flexural strength for the 7 mm-distance, followed by 14 and 21 mm. Fracture was complete only on specimens of non-reinforced groups.

  14. Effect of severely thermal shocked MWCNT enhanced glass fiber reinforced polymer composite: An emphasis on tensile and thermal responses

    Mahato, K. K.; Fulmali, A. O.; Kattaguri, R.; Dutta, K.; Prusty, R. K.; Ray, B. C.

    2018-03-01

    Fiber reinforced polymeric (FRP) composite materials are exposed to diverse changing environmental temperatures during their in-service period. Current investigation is aimed to investigate the influence of thermal-shock exposure on the mechanical behavior of multiwalled carbon nanotube (MWCNT) enhanced glass fiber reinforced polymeric (GFRP) composites. The samples were exposed to +70°C for 36 hrs followed by further exposure to ‑ 60°C for the similar interval of time. Tensile tests were conducted in order to evaluate the results of thermal-shock on the mechanical behavior of the neat and conditioned samples at 1 mm/min loading rate. The polymer phase i.e. epoxy was modified with various MWCNT content. The ultimate tensile strength (UTS) was raised by 15.11 % with increase in the 0.1 % MWCNT content GFRP as related to the thermal-shocked neat GFRP conditioned samples. The possible reason may be attributed to the variation in the coefficients of thermal expansion at the time of conditioning. Also, upto some extent the pre-existing residual stresses allows uniform distribution of stress and hence the reason in enhanced mechanical properties of GFRP and MWCNT filled composites. In order to access the modifications in the glass transition temperature (Tg) due to the addition of MWCNT in GFRP composite and also due to the thermal shock temperature modulated differential scanning calorimeter (TMDSC) measurements are carried out. Scanning electron microscopy(SEM) was carried out to identify different modes of failures and strengthening morphology in the composites.

  15. Morphology of root canal surface: A reflection on the process of cementation of the composite relined glass fiber post

    Yasmine Mendes Pupo

    2017-01-01

    Full Text Available Background: The present study was conducted to evaluate the bond strength in the different root thirds (premolars and maxillary central incisors of composite relined glass fiber posts compared to untreated glass fiber posts cemented with dual- or chemical-cure cements. Materials and Methods: Sixty human single-rooted premolars (flat canal (n = 15 and 12 maxillary central incisors were used (round canal (n = 3. The teeth were sectioned, and the roots received endodontic treatment. The standardized preparation of the canals was carried out, and the roots were randomly divided into four groups according to the cementation systems: G1: cemented posts (dual: Ambar/Allcem; G2: relined posts (dual: Ambar/Allcem; G3: cemented posts (chemical: Fusion Duralink/Cement Post; and G4: relined posts (chemical: Fusion Duralink/Cement Post. The roots were cut to give two slices of each third of the root canal per specimen. Push-out test was conducted at a speed of 0.5 mm/min. Data were analyzed by analysis of variance and Tukey's post hoc test (α = 0.05. Results: There was no statistically significant difference between groups for the premolars (flat canal (P = 0.959. There was a significant difference in the central incisors between the middle and apical thirds in the cemented group when using the dual system (P = 0.04 and between the middle and apical thirds (P = 0.003 and cervical and apical thirds (P = 0.033 when using the chemical system. Conclusion: Due to the anatomy of the root canal, flat canal of the premolars does not require relining, but round canal of the maxillary central incisors demands it for more secure in the bond strength.

  16. The effect of joint surface contours and glass fiber reinforcement on the transverse strength of repaired acrylic resin: An in vitro study

    Nayana Anasane

    2013-01-01

    Full Text Available Background : Denture fracture is an unresolved problem in complete denture prosthodontics. However, the repaired denture often experiences a refracture at the repaired site due to poor transverse strength. Hence, this study was conducted to evaluate the effect of joint surface contours and glass fiber reinforcement on the transverse strength of repaired acrylic resins. Materials and Methods: A total of 135 specimens of heat polymerized polymethyl methacrylate resin of dimensions 64 × 10 × 2.5 mm were fabricated. Fifteen intact specimens served as the control and 120 test specimens were divided into four groups (30 specimens each, depending upon the joint surface contour (butt, bevel, rabbet and round, with two subgroups based on type of the repair. Half of the specimens were repaired with plain repair resin and the other half with glass fibers reinforced repair resin. Transverse strength of the specimens was determined using three-point bending test. The results were analyzed using one-way ANOVA and Tukey post-hoc test (α= 0.05. Results: Transverse strength values for all repaired groups were significantly lower than those for the control group ( P < 0.001 (88.77 MPa, with exception of round surface design repaired with glass fiber reinforced repair resin (89.92 MPa which was significantly superior to the other joint surface contours ( P < 0.001. Glass fiber reinforced resin significantly improved the repaired denture base resins as compared to the plain repair resin ( P < 0.001. Conclusion: Specimens repaired with glass fiber reinforced resin and round surface design exhibited highest transverse strength; hence, it can be advocated for repair of denture base resins.

  17. Broad bandwidth and 600 μm length photonic crystal fiber polarization filter at the communication window of 1.55 μm

    Zhang, Zhen; Li, Shuguang; Liu, Qiang; Zhang, Shuhuan; Wang, Yujun; Wu, Junjun

    2018-02-01

    A broad bandwidth and 600-μm length photonic crystal fiber polarization filter at the communication window of 1.55 μm is proposed. The physical parameters are analyzed by the finite element method. In the structure, the loss is 705.81 dB/cm for y-polarized mode and 24.06 dB/cm for x-polarized mode at the wavelength of 1.55 μm; the y-polarized mode will be filtered out because of this property. The bandwidth of an extinction ratio (ER) better than -20 dB is 65 nm when the filter length is 600 μm, and the ER is -41 dB at the communication wavelength of 1.55 μm. The filter structure is simple and easy to produce, and it can be used to produce a single-polarization filter.

  18. High-resolution low-frequency fluctuation map of a multimode laser diode subject to filtered optical feedback via a fiber Bragg grating.

    Baladi, Fadwa; Lee, Min Won; Burie, Jean-René; Bettiati, Mauro A; Boudrioua, Azzedine; Fischer, Alexis P A

    2016-07-01

    A highly detailed and extended map of low-frequency fluctuations is established for a high-power multi-mode 980 nm laser diode subject to filtered optical feedback from a fiber Bragg grating. The low-frequency fluctuations limits and substructures exhibit substantial differences with previous works.

  19. EFFECT OF GAMMA RAY IRRADIATION ON INTERLAMINAR SHEAR STRENGTH OF GLASS FIBER REINFORCED PLASTICS AT 77 K

    Nishimura, A.; Nishijima, S.; Izumi, Y.

    2008-01-01

    It is known that an organic material is damaged by gamma ray irradiation, and the strength after irradiation has dependence on the gamma ray dose. These issues are important not only to make global understanding of electric insulating performance of glass fiber reinforced plastics (GFRP) under irradiation condition but also to develop new insulation materials. This paper presents the dependence of fracture mode and interlaminar shear strength (ILSS) on the material and the gamma ray irradiation effect on the fracture mode and the ILSS. 6 mm radius loading nose and supports were used to prompt ILS fracture for a short beam test. A 2.5 mm thick small specimen machined out of a 13 mm thick G-10CR GFRP plate (sliced specimen) showed lower ILSS and translaminar shear (TLS) fracture, although the same size specimen prepared from a 2.5 mm G-10CR GFRP plate (non-sliced specimen) showed ILS fracture and the higher ILSS. Both type of specimens showed the degradation of ILSS after gamma ray irradiation. The fracture mode of the non-sliced specimen changed from ILS to TLS fracture and no bending fracture was observed. The resistance to shear deformation of glass cloth/epoxy laminate structure would be damaged by the irradiation

  20. Design of Electrically Conductive Structural Composites by Modulating Aligned CVD-Grown Carbon Nanotube Length on Glass Fibers.

    He, Delong; Fan, Benhui; Zhao, Hang; Lu, Xiaoxin; Yang, Minhao; Liu, Yu; Bai, Jinbo

    2017-01-25

    Function-integration in glass fiber (GF) reinforced polymer composites is highly desired for developing lightweight structures and devices with improved performance and structural health monitoring. In this study, homogeneously aligned carbon nanotube (CNT) shell was in situ grafted on GF by chemical vapor deposition (CVD). It was demonstrated that the CNT shell thickness and weight fraction can be modulated by controlling the CVD conditions. The obtained hierarchical CNTs-GF/epoxy composites show highly improved electrical conductivity and thermo-mechanical and flexural properties. The composite through-plane and in-plane electrical conductivities increase from a quasi-isolator value to ∼3.5 and 100 S/m, respectively, when the weight fraction of CNTs grafted on GF fabric varies from 0% to 7%, respectively. Meanwhile, the composite storage modulus and flexural modulus and strength improve as high as 12%, 21%, and 26%, respectively, with 100% retention of the glass transition temperature. The reinforcing mechanisms are investigated by analyzing the composite microstructure and the interfacial adhesion and wetting properties of CNTs-GF hybrids. Moreover, the specific damage-related resistance variation characteristics could be employed to in situ monitor the structural health state of the composites. The outstanding electrical and structural properties of the CNTs-GF composites were due to the specific interfacial and interphase structures created by homogeneously grafting aligned CNTs on each GF of the fabric.

  1. Development of acid-resistant HEPA filter components

    Terada, K.; Woodard, R.W.; Buttedahl, O.I.

    1981-01-01

    Laboratory and in-service tests of various HEPA filter media and separators were conducted to establish their relative resistances to HNO 3 -HF vapors. Filter medium of glass fiber with Nomex additive and aluminum separators with an epoxy-vinyl coating have performed quite well in the acid environment in the laboratory, and in prototype-filters placed in service in a plenum at Rocky Flats. Proprietary filters with new design and/or components were also tested in service with generally good results

  2. Mode-locked ytterbium fiber lasers using a large modulation depth carbon nanotube saturable absorber without an additional spectral filter

    Pan, Y Z; Miao, J G; Liu, W J; Huang, X J; Wang, Y B

    2014-01-01

    We demonstrate an all-normal-dispersion ytterbium (Yb)-doped fiber laser mode-locked by a higher modulation depth carbon nanotube saturable absorber (CNT-SA) based on an evanescent field interaction scheme. The laser cavity consists of pure normal dispersion fibers without dispersion compensation and an additional spectral filter. It is exhibited that the higher modulation depth CNT-SA could contribute to stabilize the mode-locking operation within a limited range of pump power and generate the highly chirped pulses with a high-energy level in the cavity with large normal dispersion and strong nonlinearity. Stable mode-locked pulses with a maximal energy of 29 nJ with a 5.59 MHz repetition rate at the operating wavelength around 1085 nm have been obtained. The maximal time-bandwidth product is 262.4. The temporal and spectral characteristics of pulses versus pump power are demonstrated. The experimental results suggest that the CNT-SA provides a sufficient nonlinear loss to compensate high nonlinearity and catch up the gain at a different pump power and thus leads to the stable mode locking. (letter)

  3. Radiotherapy fiber dosimeter probes based on silver-only coated hollow glass waveguides

    Darafsheh, Arash; Melzer, Jeffrey E.; Harrington, James A.; Kassaee, Alireza; Finlay, Jarod C.

    2018-01-01

    Manifestation of Čerenkov radiation as a contaminating signal is a significant issue in radiation therapy dose measurement by fiber-coupled scintillator dosimeters. To enhance the scintillation signal transmission while minimizing Čerenkov radiation contamination, we designed a fiber probe using a silver-only coated hollow waveguide (HWG). The HWG with scintillator inserted in its tip, embedded in tissue-mimicking phantoms, was irradiated with clinical electron and photon beams generated by a medical linear accelerator. Optical spectra of the irradiated tip were taken using a fiber spectrometer, and the signal was deconvolved with a linear fitting algorithm. The resultant decomposed spectra of the scintillator with and without Čerenkov correction were in agreement with measurements performed by a standard electron diode and ion chamber for electron and photon beam dosimetry, respectively, indicating the minimal effect of Čerenkov contamination in the HWG-based dosimeter. Furthermore, compared with a silver/dielectric-coated HWG fiber dosimeter design, we observed higher signal transmission in the design based on the use of silver-only HWG.

  4. Investigation on Er{sup 3+}/Ho{sup 3+} co-doped silicate glass for ~2 µm fiber lasers

    Liu, Xueqiang; Huang, Feifei; Cheng, Jimeng; Fan, Xiaokang; Gao, Song [Key Laboratory of Materials for High Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Graduate School of Chinese Academy of Science, Beijing 100039 (China); Zhang, Junjie [College of Materials Science and Technology, China Jiliang University, Hangzhou 310018 (China); Hu, Lili [Key Laboratory of Materials for High Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Chen, Danping, E-mail: dpchen2008@aliyun.com [Key Laboratory of Materials for High Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China)

    2015-06-15

    A stable Er{sup 3+}/Ho{sup 3+} co-doped lead silicate glass is developed. Luminescent properties are recorded under pumping with 808 and 1550 nm lasers. Energy-transfer mechanism and efficiency are analyzed. Energy-transfer efficiency from Er{sup 3+}:{sup 4}I{sub 13/2} to Ho{sup 3+}:{sup 5}I{sub 7} reaches 93.8% at 3 mol% Ho{sub 2}O{sub 3} doping concentration. Strong luminescence is detected when pumped at 1550 nm because of efficient energy transfer from Er{sup 3+}:{sup 4}I{sub 13/2} to Ho{sup 3+}:{sup 5}I{sub 7}. Peak gain coefficient at 2056 nm is detected as 1.62 cm{sup −1}. The excellent luminescent property and high stability indicate that Er{sup 3+}/Ho{sup 3+} co-doped lead silicate glass can be applied in 2 µm fiber lasers. - Highlights: • Er{sup 3+}/Ho{sup 3+} co-doped silicate glasses with high stability are prepared. • Strong luminescence is detected under pump of 1550 nm lasers owing to efficient energy transfer from Er{sup 3+} to Ho{sup 3+}. • Transfer efficiency is calculated to be 93.8% when Ho{sub 2}O{sub 3} doping concentration is up to 3 mol%. • Gain coefficient peaks at 2056 nm to be 1.62 cm{sup −1}.

  5. Tunable and switchable dual-wavelength single polarization narrow linewidth SLM erbium-doped fiber laser based on a PM-CMFBG filter.

    Yin, Bin; Feng, Suchun; Liu, Zhibo; Bai, Yunlong; Jian, Shuisheng

    2014-09-22

    A tunable and switchable dual-wavelength single polarization narrow linewidth single-longitudinal-mode (SLM) erbium-doped fiber (EDF) ring laser based on polarization-maintaining chirped moiré fiber Bragg grating (PM-CMFBG) filter is proposed and demonstrated. For the first time as we know, the CMFBG inscribed on the PM fiber is applied for the wavelength-tunable and-switchable dual-wavelength laser. The PM-CMFBG filter with ultra-narrow transmission band (0.1 pm) and a uniform polarization-maintaining fiber Bragg grating (PM-FBG) are used to select the laser longitudinal mode. The stable single polarization SLM operation is guaranteed by the PM-CMFBG filter and polarization controller. A tuning range of about 0.25 nm with about 0.075 nm step is achieved by stretching the uniform PM-FBG. Meanwhile, the linewidth of the fiber laser for each wavelength is approximate 6.5 and 7.1 kHz with a 20 dB linewidth, which indicates the laser linewidth is approximate 325 Hz and 355 Hz FWHM.

  6. Interface enhancement of glass fiber reinforced vinyl ester composites with flame-synthesized carbon nanotubes and its enhancing mechanism.

    Liao, Lingmin; Wang, Xiao; Fang, Pengfei; Liew, Kim Meow; Pan, Chunxu

    2011-02-01

    Interface enhancement with carbon nanotubes (CNTs) provides a promising approach for improving shock strength and toughness of glass fiber reinforced plastic (GFRP) composites. The effects of incorporating flame-synthesized CNTs (F-CNTs) into GFRP were studied, including on hand lay-up preparation, microstructural characterization, mechanical properties, fracture morphologies, and theoretical calculation. The experimental results showed that: (1) the impact strength of the GFRP modified by F-CNTs increased by more than 15% over that of the GFRP modified by CNTs from chemical vapor deposition; and (2) with the F-CNT enhancement, no interfacial debonding was observed at the interface between the fiber and resin matrix on the GFRP fracture surface, which indicated strong adhesive strength between them. The theoretical calculation revealed that the intrinsic characteristics of the F-CNTs, including lower crystallinity with a large number of defects and chemical functional groups on the surface, promoted their surface activity and dispersibility at the interface, which improved the interfacial bond strength of GFRP.

  7. Tunable and switchable all-fiber comb filter using a PBS-based two-stage cascaded Mach-Zehnder interferometer

    Luo, Zhi-Chao; Luo, Ai-Ping; Xu, Wen-Cheng

    2011-08-01

    We propose and demonstrate a novel tunable and switchable all-fiber comb filter by employing a polarization beam splitter (PBS)-based two-stage cascaded Mach-Zehnder (M-Z) interferometer. The proposed comb filter consists of a rotatable polarizer, a fiber PBS, a non-3-dB coupler and a 3-dB coupler. By simply adjusting the polarization state of the input light, the dual-function of channel spacing tunable and wavelength switchable (interleaving) operations can be efficiently obtained. The theoretical analysis is verified by the experimental results. A comb filter with both the channel spacing tunable from 0.18 nm to 0.36 nm and the wavelength switchable functions is experimentally demonstrated.

  8. Glass and cellulose acetate fibers-supported boehmite nanosheets for bacteria adsorption

    N.V. Svarovskaya

    2017-04-01

    Full Text Available In this work, in situ method of producing hybrid fibrous adsorbents in which boehmite nanosheets with high sorption properties formed on the surface of hydrophilic microfibres, such as cellulose acetate and glass fibre, was described. The boehmite nanosheets were fabricated by the reaction of composite AlN/Al nanoparticles with water at 60 °C. The synthesized samples were characterized by X-ray diffractometer, scanning, transmission electron microscopy, Fourier transform infrared spectrometer (FT-IR, zeta-potential and specific surface area analyzers. The introduction of microfibres into a diluted aqueous suspension of nanopowders causes heteroadagulation of the nanoparticles and accelerates their further transformation. This effect is most substantial with the glass microfibre, which is thought to have a higher concentration of surface groups capable of generating hydrogen bonds that act as heteroadagulation and nucleation centres. The experimental results showed that the morphology of the resultant hybrid fibrous adsorbents differed accordingly: the nanosheets were attached on-edge to the glass microfibre surface, while on the surface of the cellulose acetate microfibre, they were secured in the form of spherical “nanoflowers” of agglomerated nanosheets. The effect of the morphology of hybrid fibrous adsorbents on adsorption bacteria Escherichia coli was also investigated.

  9. SU-F-J-28: Development of a New Imaging Filter to Remove the Shadows From the Carbon Fiber Grid Table Top

    Maehana, W [Kanagawa Cancer Center, Yokohama, Kanagawa (Japan); Yokohama National University, Yokohama, kanagawa (Japan); Nagao, T [Yokohama National University, Yokohama, kanagawa (Japan)

    2016-06-15

    Purpose: For the image guided radiation therapy (IGRT), the shadows caused by the construction of the treatment couch top adversely affect the visual evaluation. Therefore, we developed the new imaging filter in order to remove the shadows. The performance of the new filter was evaluated using the clinical images. Methods: The new filter was composed of the band-pass filter (BPF) weighted by the k factor and the low-pass filter (LPF). In the frequency region, the stop bandwidth were 8.3×10{sup 3} mm{sup −1} on u direction and 11.1×10{sup 3} mm{sup −1} on v direction for the BPF, and the pass bandwidth were 8.3×10{sup 3} mm{sup −1} on u direction and 11.1×10{sup 3} mm{sup −1} on v direction for the LPF. After adding the filter, the shadows from the carbon fiber grid table top (CFGTT, Varian) on the kV-image was removed. To check the filter effect, we compared the clinical images, which are thorax and thoracoabdominal region, with to without the filter. The subjective evaluation tests was performed by adapting a three-point scale (agree, neither agree nor disagree, disagree) about the 15 persons in the department of radiation oncology. Results: We succeeded in removing all shadows of CFGTT using the new filter. This filter is very useful shown by the results of the subjective evaluation having the 23/30 persons agreed to the filtered clinical images. Conclusion: We concluded that the proposed method was useful tool for the IGRT and the new filter leads to improvement of the accuracy of radiation therapy.

  10. CHARACTERIZATION OF THE FORMATION OF FILTER PAPER USING THE BARTLETT SPECTRUM OF THE FIBER STRUCTURE

    Martin Lehmann

    2013-06-01

    Full Text Available The formation index of filter paper is one of the most important characteristics used in industrial quality control. Its estimation is often based on subjective comparison chart rating or, even more objective, on the power spectrum of the paper structure observed on a transmission light table. It is shown that paper formation can be modeled as Gaussian random fields with a well defined class of correlation functions, and a formation index can be derived from the density of the Bartlett spectrum estimated from image data. More precisely, the formation index is the mean of the Bessel transform of the correlation taken for wave lengths between 2 and 5 mm.

  11. Effect of Fiber Volume Fraction and Water Absorption toward Bending Strength of Coconut Filters/ Polyester Composite

    I Putu Lokantara

    2012-11-01

    Full Text Available The variation of fibre volume and the duration of water soaking take influence on the mechanical properties of composite. This research aim is to know the influence of fraction volume fibre and soaking duration on the mineral watertoward the tensile strength and flexural of polyester-coconut-tapis composite. This research used coconut-tapis fibre which is cut 1 cm in length with 0%, 5%, 7,5%, and 10% fiber volume fraction, unsaturated-polyester (UPRs matrix resin type Yucalac 157 BQTN-EX, and MEKPO hardener. The flexure specimen are made by press hand lay-up method and cut according ASTM D790-03 for the flexure test. The result of flexure test shows that the duration of soaking and the fiber volume fraction give a significant effect on the flexural strength of composite. The highest strength are reached by composite with 10% fibre volume on 48 hour soaking time equal to 41.994 MPa. The flexure modulus happenend shows increasing until 24 hour soaking time. The highest modulus are reached by composite with 10% fibre volume equal to 7.114 GPa while the lowest are reached by composite with 0% fibre volume equal to 3,023 GPa.

  12. FIBER OPTICS: Role of point defects in the photosensitivity of hydrogen-loaded phosphosilicate glass

    Larionov, Yu V.

    2010-08-01

    It is shown that point defect modifications in hydrogen-loaded phosphosilicate glass (PSG) do not play a central role in determining its photosensitivity. Photochemical reactions that involve a two-step point defect modification and pre-exposure effect are incapable of accounting for photoinduced refractive index changes. It seems likely that a key role in UV-induced refractive index modifications is played by structural changes in the PSG network. Experimental data are presented that demonstrate intricate network rearrangement dynamics during UV exposure of PSG.

  13. Preparation of Ho3+/Tm3+ Co-doped Lanthanum Tungsten Germanium Tellurite Glass Fiber and Its Laser Performance for 2.0 μm

    Zhou, Dechun; Bai, Xuemei; Zhou, Hang

    2017-03-01

    Ho3+/Tm3+ co-doped 50TeO2-25GeO2-3WO3-5La2O3-3Nb2O5-5Li2O-9BaF2 glass fiber is prepared with the rod-tube drawing method of 15 μm core diameter and 125 μm inner cladding diameter applied in the 2.0 μm-infrared laser. The 2.0 μm luminescence properties of the core glass are researched and the fluorescence intensity variation for different Tm3+ doping concentration is systematically analyzed. The results show that the 2.0 μm luminescence of Ho3+ is greatly influenced by the doping concentration ratio of Ho3+ to Tm3+ and that the maximum fluorescence intensity of the core glass can be obtained and its emission cross section can reach 0.933 × 10-21 cm2 when the sensitized proportion of holmium to thulium is 0.3 to 0.7 (mol%). Simultaneously, the maximum phonon energy of the core glass sample is 753 cm-1, which is significantly lower than that of silicate, gallate and germanate glass and the smaller matrix phonon energy can be conductive to the increase 2.0 μm-band emission intensity. The continuous laser with the maximum laser output power of 0.993 W and 2051 nm -wavelength of 31.9%-slope efficiency is output within the 0.5 m glass fiber and the experiment adopts 1560 nm erbium-doped fiber laser(EDFL) as the pump source and the self-built all-fiber laser. Therefore, the glass fiber has excellent laser characteristics and it is suitable for the 2.0 μm-band laser.

  14. In-Situ Phase Transition Control in the Supercooled State for Robust Active Glass Fiber.

    Lv, Shichao; Cao, Maoqing; Li, Chaoyu; Li, Jiang; Qiu, Jianrong; Zhou, Shifeng

    2017-06-21

    The construction of a dopant-activated photonic composite is of great technological importance for various applications, including smart lighting, optical amplification, laser, and optical detection. The bonding arrangement around the introduced dopants largely determines the properties, yet it remains a daunting challenge to manipulate the local state of the matrix (i.e., phase) inside the transparent composite in a controllable manner. Here we demonstrate that the relaxation of the supercooled state enables in-situ phase transition control in glass. Benefiting from the unique local atom arrangement manner, the strategy offers the possibility for simultaneously tuning the chemical environment of the incorporated dopant and engineering the dopant-host interaction. This allows us to effectively activate the dopant with high efficiency (calculated as ∼100%) and profoundly enhance the dopant-host energy-exchange interaction. Our results highlight that the in-situ phase transition control in glass may provide new opportunities for fabrication of unusual photonic materials with intense broadband emission at ∼1100 nm and development of the robust optical detection unit with high compactness and broadband photon-harvesting capability (from X-ray to ultraviolet light).

  15. The Effect of Temperature and Nanoclay on the Low Velocity and Ballistic Behavior of Woven Glass-Fiber Reinforced Composites

    Patrin, Lauren

    The objective of this research was to study the effect of nanoclay and temperature on the behavior of woven glass-fabric reinforced epoxy composite under low velocity and ballistic impacts. The materials used in manufacturing the composite were S2 (6181) glass-fibers, epoxy resin (EPON 828), hardener (Epikure 3230), nanoclay and Heloxy 61 modifier. The nanoclay addition was 0%, 1%, 3% and 5% by weight, with respect to the resin. All specimens were manufactured at the City College facilities using vacuum infusion. Tensile tests were conducted to characterize the material and obtain the Young's modulus, ultimate stress, failure strain, Poisson's ratio, shear modulus and shear strength and their variation with nanoclay percentage and temperature. The tests were conducted at room temperature (21°C/70°F), -54°C (-65°F), -20°C (-4°F), 49°C (120°F) and 71°C (160°F). Next composite specimens with 0%, 1%, 3% and 5% nanoclay by weight, with respect to the resin, were subjected to low velocity impact at the previously specified temperatures to determine dynamic force, displacement and energy correlations. The extent of damage was studied using the ultrasound technique. Then ballistic tests were conducted on the nanoclay infused specimens at room temperature to obtain the ballistic limit (V50) and the damage behavior of the composite. The dynamic finite element analysis (FEA) software LS-DYNA was used to model and simulate the results of low velocity impact tests. Good agreement was obtained between experimental and numerical (FEA) results. Analytical analyses were undertaken to compare the results from the tensile experiments. The finite element analysis (FEA) allowed for further analytical comparison of the results. The FEA platform used was LS-DYNA due to its proficient dynamic and damage capabilities in composite materials. The FEA was used to model and simulate the low velocity impacts and compare the results to experiments.

  16. In vivo testing of a biodegradable woven fabric made of bioactive glass fibers and PLGA80--a pilot study in the rabbit.

    Alm, Jessica J; Frantzén, Janek P A; Moritz, Niko; Lankinen, Petteri; Tukiainen, Mikko; Kellomäki, Minna; Aro, Hannu T

    2010-05-01

    The purpose of this study was to perform an intra-animal comparison of biodegradable woven fabrics made of bioactive glass (BG) fibers and poly(L-lactide-co-glycolide) 80/20 copolymer (PLGA(80)) fibers or PLGA(80) fibers alone, in surgical stabilization of bone graft. The BG fibers (BG 1-98) were aimed to enhance bone growth at site of bone grafting, whereas the PLGA component was intended to provide structural strength and flexibility to the fabric. Bone formation was analyzed qualitatively by histology and quantitatively by peripheral quantitative computed tomography (pQCT) at 12 weeks. The surgical handling properties of the control PLGA(80) fabric were more favorable. Both fabrics were integrated with the cortical bone surfaces, but BG fibers showed almost complete resorption. There were no signs of adverse local tissue reactions. As a proof of material integration and induced new bone formation, there was a significant increase in bone volume of the operated femurs compared with the contralateral intact bone (25% with BG/PLGA(80) fabric, p < 0.001 and 28% with the control PLGA(80) fabric, p = 0.006). This study failed to demonstrate the previously seen positive effect of BG 1-98 on osteogenesis, probably due to the changed resorption properties of BG in the form of fibers. Therefore, the feasibility and safety of BG as fibers needs to be reevaluated before use in clinical applications. (c) 2010 Wiley Periodicals, Inc.

  17. The use of laboratory sand, soil and crushed-glass filter columns for polishing domestic-strength synthetic wastewater that has undergone secondary treatment.

    Healy, M G; Burke, P; Rodgers, M

    2010-10-01

    The aim of this study was to examine the performance of intermittently loaded, 150 mm-diameter stratified filter columns of 2 depths (0.65 and 0.375 m) comprising different media--sand, crushed glass and soil--in polishing the effluent from a laboratory horizontal flow biofilm reactor (HFBR) treating synthetic domestic-strength wastewater. The HFBR has been successfully used to remove organic carbon and ammonium-nitrogen (NH4-N) from domestic wastewater. In this treatment method, wastewater is allowed to flow over and back along a stack of polyvinyl chloride (PVC) sheets. Biofilms on the sheets reduce organic carbon, suspended matter, and nutrients in the wastewater, but to achieve the quality of a septic tank system, additional treatment is required. In all filters, at a hydraulic loading rate of 100 L m(-2) d(-1), 40-65% of chemical oxygen demand (COD) and practically 100% of total suspended solids (TSS) were removed, nitrification was complete, and bacterial numbers were reduced by over 80%, with best removals achieved in the soil filters (93%). Soil polishing filters with the depth of 0.65 m performed best in terms of organic carbon, total nitrogen (Tot-N) and bacterial removal. Data from this preliminary study are useful in the design of treatment systems to polish secondary wastewaters with similar water quality characteristics.

  18. Combination of highly nonlinear fiber, an optical bandpass filter, and a Fabry-Perot filter to improve the signal-to-noise ratio of a supercontinuum continuous-wave optical source.

    Nan, Yinbo; Huo, Li; Lou, Caiyun

    2005-05-20

    We present a theoretical study of a supercontinuum (SC) continuous-wave (cw) optical source generation in highly nonlinear fiber and its noise properties through numerical simulations based on the nonlinear Schrödinger equation. Fluctuations of pump pulses generate substructures between the longitudinal modes that result in the generation of white noise and then in degradation of coherence and in a decrease of the modulation depths and the signal-to-noise ratio (SNR). A scheme for improvement of the SNR of a multiwavelength cw optical source based on a SC by use of the combination of a highly nonlinear fiber (HNLF), an optical bandpass filter, and a Fabry-Perot (FP) filter is presented. Numerical simulations show that the improvement in modulation depth is relative to the HNLF's length, the 3-dB bandwidth of the optical bandpass filter, and the reflection ratio of the FP filter and that the average improvement in modulation depth is 13.7 dB under specified conditions.

  19. Preparation and investigation of [GeSe4]100-xIx glasses as promising materials for infrared fiber sensors

    Velmuzhov, A. P.; Sukhanov, M. V.; Shiryaev, V. S.; Plekhovich, A. D.; Kotereva, T. V.; Snopatin, G. E.; Gerasimenko, V. V.; Pushkin, A. A.

    2016-10-01

    The glasses of [GeSe4]100-xIx (x = 1, 3, 5, 8, 10) compositions are prepared; their thermal properties, transparency in the mid-IR range and stability against crystallization are investigated. The glass transition temperature (Tg) in this system decreases monotonically with increasing iodine content from the value of Tg = 176 °C at x = 1 to Tg = 129 °C at x = 10. It has been determined by X-ray diffraction method that the addition of iodine reduces the volume fraction of the crystalline phase in glasses after annealing at 350 °C. Using a single crucible technique, the rod of [GeSe4]95I5 glass was drawn into a single-index fiber of 300 μm diameter and 10 m length. The optical losses were 2-3 dB/m in the spectral range 2.5-8 μm; the minimum optical losses were 1.7 dB/m at a wavelength of 5.5 μm. The content of impurity hydrogen in the form of Se-H in the fiber was about 3.6 ppm(wt), impurity oxygen in the form of Ge-O is 1 ppm(wt). The possibility of use of such [GeSe4]95I5 glass single-index fiber for infrared analysis of liquids by example of crude oil and water solutions of acetone has been demonstrated.

  20. Effect of fabrication processes on mechanical properties of glass fiber reinforced polymer composites for 49 meter (160 foot recreational yachts

    Dave (Dae-Wook Kim

    2010-03-01

    Full Text Available Polymer composite materials offer high strength and stiffness to weight ratio, corrosion resistance, and total life cost reductions that appeal to the marine industry. The advantages of composite construction have led to their incorporation in U.S. yacht hull structures over 46 meters (150 feet in length. In order to construct even larger hull structures, higher quality composites with lower cost production techniques need to be developed. In this study, the effect of composite hull fabrication processes on mechanical properties of glass fiber reinforced plastic (GFRP composites is presented. Fabrication techniques investigated during this study are hand lay-up (HL, vacuum infusion (VI, and hybrid (HL + VI processes. Mechanical property testing includes: tensile, compressive, and ignition loss sample analysis. Results demonstrate that the vacuum pressure implemented during composite fabrication has an effect on mechanical properties. The VI processed GFRP yields improved mechanical properties in tension/compression strengths and tensile modulus. The hybrid GFRP composites, however, failed in a sequential manor, due to dissimilar failure modes in the HL and VI processed sides. Fractography analysis was conducted to validate the mechanical property testing results.

  1. Effect of fabrication processes on mechanical properties of glass fiber reinforced polymer composites for 49 meter (160 foot) recreational yachts

    Kim, Dave (dea-wook); Hennigan, Daniel John; Beavers, Kevin Daniel

    2010-03-01

    Polymer composite materialsoffer high strength and stiffness to weight ratio, corrosion resistance, and total life cost reductions that appeal to the marine industry. The advantages of composite construction have led to their incorporation in U.S. yacht hull structures over 46 meters (150 feet) in length. In order to construct even larger hull structures, higher quality composites with a lower cost production techniques need to be developed. In this study, the effect of composite hull fabrication processes on mechanical properties of glass fiber reinforced plastic(GFRP) composites is presented. Fabrication techniques used in this study are hand lay-up (HL), vacuum infusion (VI), and hybrid (HL+VI) processes. Mechanical property testing includes: tensile, compressive, and ignition loss sample analysis. Results demonstrate that the vacuum pressure implemented during composite fabrication has an effect on mechanical properties. The VI processed GFRP yields improved mechanical properties in tension/compression strengths and tensile modulus. The hybrid GFRP composites, however, failed in a sequential manor, due to dissimilar failure modes in the HL and VI processed sides. Fractography analysis was conducted to validate the mechanical property testing results

  2. Development of high radiation-resistant glass fiber reinforced plastics with cyanate-based resin for superconducting magnet systems

    Idesaki, Akira, E-mail: idesaki.akira@qst.go.jp [Quantum Beam Science Directorate, Japan Atomic Energy Agency, Watanuki 1233, Takasaki, Gunma 370-1292 (Japan); Nakamoto, Tatsushi [Cryogenic Science Center, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Yoshida, Makoto [Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Shimada, Akihiko [Quantum Beam Science Directorate, Japan Atomic Energy Agency, Watanuki 1233, Takasaki, Gunma 370-1292 (Japan); Iio, Masami; Sasaki, Kenichi; Sugano, Michinaka [Cryogenic Science Center, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Makida, Yasuhiro [Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Ogitsu, Toru [Cryogenic Science Center, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan)

    2016-11-15

    Highlights: • GFRPs for superconducting magnet systems were developed. • Cyanate-based resins were used for GFRPs as matrices. • Radiation resistance was evaluated based on gas evolution and mechanical properties. • GFRP with bismaleimide-triazine resin exhibited excellent radiation resistance. - Abstract: Glass fiber reinforced plastics (GFRPs) with cyanate ester resin/epoxy resin, bismaleimide resin/epoxy resin, and bismaleimide-triazine resin as matrices were developed for the superconducting magnet systems used in high intensity accelerators. The radiation resistance of these GFRPs was evaluated based on their gas evolution and changes in their mechanical properties after gamma-ray irradiation with dose of 100 MGy in vacuum at ambient temperature. After irradiation, a small amount of gas was evolved from all of the GFRPs, and a slight decrease in mechanical properties was observed compared with the conventional epoxy resin-GFRP, G10. Among the GFRPs, the smallest amount of gas (6 × 10{sup −5} mol/g) was evolved from the GFRP with the bismaleimide-triazine resin, which also retained more than 88% of its flexural strength after 100 MGy irradiation; this GFRP is thus considered the most promising material for superconducting magnet systems.

  3. Glass Fiber Reinforced Polymer (GFRP Bars for Enhancing the Flexural Performance of RC Beams Using Side-NSM Technique

    Md. Akter Hosen

    2017-05-01

    Full Text Available Reinforced concrete (RC structures require strengthening for numerous factors, such as increased load, modification of the structural systems, structural upgrade or errors in the design and construction stages. The side near-surface mounted (SNSM strengthening technique with glass fiber-reinforced polymer (GFRP bars is a relatively new emerging technique for enhancing the flexural capacities of existing RC elements. Nine RC rectangular beams were flexurally strengthened with this technique and tested under four-point bending loads until failure. The main goal of this study is to optimize the structural capacity of the RC beams by varying the amount of strengthening reinforcement and bond length. The experimental test results showed that strengthening with SNSM GFRP bars significantly enhanced the flexural responses of the specimens compared with the control specimen. The first cracking and ultimate loads, energy absorption capacities, ductility and stiffness were remarkably enhanced by the SNSM technique. It was also confirmed that the bond length of the strengthened reinforcement greatly influences the energy absorption capacities, ductility and stiffness. The effect of the bond length on these properties is more significant compared to the amount of strengthening reinforcement.

  4. Mechanical Properties of Abutments: Resin-Bonded Glass Fiber-Reinforced Versus Titanium.

    Bassi, Mirko Andreasi; Bedini, Rosells; Pecci, Raffaela; Ioppolo, Pietro; Laritano, Dorina; Carinci, Francesco

    2016-01-01

    The clinical success and longevity of endosseous implants, after their prosthetic finalization, mainly depends on mechanical factors. Excessive mechanical stress has been shown to cause initial bone loss around implants in the presence of a rigid implant-prosthetic connection. The implant abutments are manufactured with high elastic modulus materials such as titanium, steel, precious alloys, or esthetic ceramics. These materials do not absorb any type of shock from the chewing loads or ensure protection of the bone-implant interface, especially when the esthetic restorative material is ceramic rather than composite resin. The mechanical resistance to cyclical load was evaluated in a tooth-colored fiber-reinforced abutment prototype (TCFRA) and compared to that of a similarly shaped titanium abutment (TA). Eight TCFRAs and eight TAs were adhesively cemented on as many titanium implants. The swinging the two types of abutments showed during the application of sinusoidal load was also analyzed. In the TA group, fracture and deformation occurred in 12.5% of samples, while debonding occurred in 62.5%. In the TCFRA group, only debonding was present, in 37.5% of samples. In comparison to the TAs, the TCFRAs exhibited greater swinging during the application of sinusoidal load. In the TA group extrusion prevailed, whereas in the TCFRA group intrusion was more frequent. TCFRA demonstrated a greater elasticity than did TAs to the flexural load, absorbing part of the transversal load applied on the fixture during the chewing function and thus reducing the stress on the bone-implant interface.

  5. Mechanical properties of resin glass fiber-reinforced abutment in comparison to titanium abutment

    Andreasi Bassi, Mirko; Bedini, Rossella; Pecci, Raffella; Ioppolo, Pietro; Lauritano, Dorina; Carinci, Francesco

    2015-01-01

    Purpose: So far, definitive implant abutments have been performed with high elastic modulus materials, which prevented any type of shock absorption of the chewing loads and as a consequence, the protection of the bone-fixture interface. This is particularly the case when the esthetic restorative material chosen is ceramic rather than composite resin. The adoption of an anisotropic abutment, characterized by an elastic deformability, could allow decreasing the impulse of chewing forces transmitted to the crestal bone. Materials and Methods: According to research protocol, the mechanical resistance to cyclical load was evaluated in a tooth-colored fiber-reinforced abutment (TCFRA) prototype and compared to that of a titanium abutment (TA), thus eight TCFRAs and eight TAs were adhesively cemented on as many titanium implants. The swinging that the two types of abutments showed during the application of sinusoidal load was also analyzed. Results: In the TA group, both fracture and deformation occurred in 12.5% of samples while debonding 62.5%. In the TCFRA group, only debonding was present in 37.5% of samples. In comparison to the TAs, the TCFRAs exhibited a greater swinging during the application of sinusoidal load. In the TA group, the extrusion prevailed, whereas in the TCFRA group, the intrusion was more frequent. Conclusion: The greater elasticity of TCFRA to the flexural load allows absorbing part of the transversal load applied on the fixture during the chewing function, thus reducing the stress on the bone-implant interface. PMID:26229266

  6. Enhanced bending failure strain in biological glass fibers due to internal lamellar architecture.

    Monn, Michael A; Kesari, Haneesh

    2017-12-01

    The remarkable mechanical properties of biological structures, like tooth and bone, are often a consequence of their architecture. The tree ring-like layers that comprise the skeletal elements of the marine sponge Euplectella aspergillum are a quintessential example of the intricate architectures prevalent in biological structures. These skeletal elements, known as spicules, are hair-like fibers that consist of a concentric array of silica cylinders separated by thin, organic layers. Thousands of spicules act like roots to anchor the sponge to the sea floor. While spicules have been the subject of several structure-property investigations, those studies have mostly focused on the relationship between the spicule's layered architecture and toughness properties. In contrast, we hypothesize that the spicule's layered architecture enhances its bending failure strain, thereby allowing it to provide a better anchorage to the sea floor. We test our hypothesis by performing three-point bending tests on E. aspergillum spicules, measuring their bending failure strains, and comparing them to those of spicules from a related sponge, Tethya aurantia. The T. aurantia spicules have a similar chemical composition to E. aspergillum spicules but have no architecture. Thus, any difference between the bending failure strains of the two types of spicules can be attributed to the E. aspergillum spicules' layered architecture. We found that the bending failure strains of the E. aspergillum spicules were roughly 2.4 times larger than those of the T. aurantia spicules. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Study on the Effect of Different Fe2O3/ZrO2 Ratio on the Properties of Silicate Glass Fibers

    Jianxun Liu

    2017-01-01

    Full Text Available A series of silicate glass fibers with different ratios of Fe2O3/ZrO2 were prepared, and their corrosion resistance, mass loss, and strength loss were characterized. The crystallization and melting properties of the fibers were analyzed by differential scanning calorimetry (DSC, high temperature viscometer, and high temperature microscope. The results show that the deformation temperature, sphere temperature, hemisphere temperature, and crystallization temperature of the fiber initially decrease and then increase with the increase of Fe2O3/ZrO2 ratio, while the molding temperature decreases with the increase of the ratio of Fe2O3/ZrO2. When the ratio is close to 1 : 1, its alkali resistance is almost same as that of AR-glass fiber, and the drawing process performance is better. However, with the increase of the ratio, its alkali resistance continues to decline and the poor wire drawing performance is not conducive to the drawing operation.

  8. Measurement of temperature and concentration influence on the dispersion of fused silica glass photonic crystal fiber infiltrated with water-ethanol mixture

    Van, Hieu Le; Buczynski, Ryszard; Long, Van Cao; Trippenbach, Marek; Borzycki, Krzysztof; Manh, An Nguyen; Kasztelanic, Rafal

    2018-01-01

    We present experimental and simulation results of the zero-dispersion shift in photonics crystal fibers infiltrated with water-ethanol mixture. The fiber based on the fused silica glass with a hexagonal lattice consists of seven rings of air-holes filled by liquid. We show that it is possible to shift the zero-dispersion wavelength by 35 ps/nm/km when changing the temperature by 60 °C, and by 42 ps/nm/km when changing the concentration of ethanol from 0 to 100%. The results also show that for the optical fiber filed with pure ethanol the flattened part of the dispersion shifts from anomalous to the normal regime at temperatures below -70 °C.

  9. Visible and near infrared up-conversion luminescence in Yb3+/Tm3+ co-doped yttria-alumino-silicate glass based optical fibers

    Halder, Arindam; Chandra Paul, Mukul; Wadi Harun, Sulaiman; Kumar Bhadra, Shyamal; Bysakh, Sandip; Das, Shyamal; Pal, Mrinmay

    2013-01-01

    We report blue light up-conversion (UC) emission in Yb–Tm co-doped nano-phase separated yttria-alumino-silicate (YAS) glass based D-shaped with low-index cladding optical fibers. Y 2 O 3 creates an environment of nano structured YAS glass phases with Yb and Tm rich zone into the core glass which confirmed from TEM analyses. This kind of glass host assists in distributing of Yb and Tm rich zone uniformly throughout the core region. Yb and Tm doped regions exist mainly into nano YAS phases, defined as RE rich nano YAS-RE phases. All samples exhibit UC luminescence peaks at 483 nm, 650 nm and 817 nm for Tm 3+ and 1044 nm for Yb 3+ under excitation by 975 nm laser light. In such type of nano-engineered glass–ceramic based host, almost all the Yb ions transferred its energy to the nearer Tm ions. In particular 483 nm emission is attributed to 1 G 4 → 3 H 6 transition through a three step resonance energy transfer (ET) from excited Yb 3+ . The highest emission intensity is obtained with a concentration of 0.5 wt% Tm 3+ and 2.0 wt% Yb 3+ . The ET between Yb 3+ and Tm 3+ is increased with increase of Yb 3+ concentration with respect to Tm 3+ . The experimental fluorescence life-times of Tm 3+ upconversion emission at visible wavelengths into such kind of fiber is reported under 975 nm pump excitation. The present study is important for development of an efficient tunable 483 nm fluorescence light source. -- Highlights: • We report nano-phase separated YAS glass host based Yb–Tm co-doped optical fibers. • Almost all the Yb transferred its energy to the neighboring Tm ions. • We report strong UC luminescence peaks at 483 nm and 817 nm wavelengths. • We report third ET coefficient as 1.6723 Hz for such kind of Yb–Tm codoped fiber. • We report suitable fiber as an efficient tunable 483 nm fluorescence light source

  10. Polarization filtering in the visible wavelength range using surface plasmon resonance and a sunflower-type photonic quasi-crystal fiber

    Yan, Bei; Wang, Anran; Liu, Exian; Tan, Wei; Xie, Jianlan; Ge, Rui; Liu, Jianjun

    2018-04-01

    A novel polarization filter based on a sunflower-type photonic quasi-crystal fiber (PQF) is proposed in this paper. We also discuss different methods to tune the filter wavelength. The proposed filter can efficiently produce polarized light with visible wavelengths by using the resonance between the second-order surface plasmon polariton mode and the core mode of the PQF. The filtered wavelength can be tuned between 0.55 µm and 0.68 µm by adjusting the thickness of the gold film. When the thickness of the gold film is 25.3 nm, the resonance loss in the y-polarized direction reaches 11707 dB m‑1 for a wavelength of 0.6326 µm, and the full width at half maximum is only 5 nm. Due to the flexible design and absence of both polarization coupling and polarization dispersion, this polarization filter can be used in devices that require narrow-band filtering.

  11. Tunable ultra-broadband polarization filter based on three-core resonance of the fluid-infiltrated and gold-coated photonic crystal fiber

    Liu, Yingchao; Chen, Hailiang; Ma, Mingjian; Zhang, Wenxun; Wang, Yujun; Li, Shuguang

    2018-03-01

    We propose a tunable ultra-broadband polarization filter based on three-core resonance of the fluid-infiltrated and gold-coated high birefringent photonic crystal fiber (HB-PCF). Gold film was applied to the inner walls of two cladding air holes and surface plasmon polaritons were generated on its surface. The two gold-coated cladding air holes acted as two defective cores. As the phase matching condition was satisfied, light transmitted in the fiber core and coupled to the two defective cores. The three-core PCF supported three super modes in two orthogonal polarization directions. The coupling characteristics among these modes were investigated using the finite-element method. We found that the coupling wavelengths and strength between these guided modes can be tuned by altering the structural parameters of the designed HB-PCF, such as the size of the voids, thickness of the gold-films and liquid infilling pattern. Under the optimized structural parameters, a tunable broadband polarization filter was realized. For one liquid infilling pattern, we obtained a broadband polarization filter which filtered out the light in y-polarization direction at the wavelength of 1550 nm. For another liquid infilling pattern, we filtered out light in the x-polarization direction at the wavelength of 1310 nm. Our studies on the designed HB-PCF made contributions to the further devising of tunable broadband polarization filters, which are extensively used in telecommunication and sensor systems. Project supported by the National Natural Science Foundation of China (Grant Nos. 61505175 and 61475134) and the Natural Science Foundation of Hebei Province (Grant Nos. F2017203110 and F2017203193).

  12. Constitutive modelling of creep in a long fiber random glass mat thermoplastic composite

    Dasappa, Prasad

    The primary objective of this proposed research is to characterize and model the creep behaviour of Glass Mat Thermoplastic (GMT) composites under thermo-mechanical loads. In addition, tensile testing has been performed to study the variability in mechanical properties. The thermo-physical properties of the polypropylene matrix including crystallinity level, transitions and the variation of the stiffness with temperature have also been determined. In this work, the creep of a long fibre GMT composite has been investigated for a relatively wide range of stresses from 5 to 80 MPa and temperatures from 25 to 90°C. The higher limit for stress is approximately 90% of the nominal tensile strength of the material. A Design of Experiments (ANOVA) statistical method was applied to determine the effects of stress and temperature in the random mat material which is known for wild experimental scatter. Two sets of creep tests were conducted. First, preliminary short-term creep tests consisting of 30 minutes creep followed by recovery were carried out over a wide range of stresses and temperatures. These tests were carried out to determine the linear viscoelastic region of the material. From these tests, the material was found to be linear viscoelastic up-to 20 MPa at room temperature and considerable non-linearities were observed with both stress and temperature. Using Time-Temperature superposition (TTS) a long term master curve for creep compliance for up-to 185 years at room temperature has been obtained. Further, viscoplastic strains were developed in these tests indicating the need for a non-linear viscoelastic viscoplastic constitutive model. The second set of creep tests was performed to develop a general non-linear viscoelastic viscoplastic constitutive model. Long term creep-recovery tests consisting of 1 day creep followed by recovery has been conducted over the stress range between 20 and 70 MPa at four temperatures: 25°C, 40°C, 60°C and 80°C. Findley's model

  13. Study of loading/air back-pulse cleaning cycles on the performance of ceramic membrane filters

    Waggoner, Charles; Alderman, Steven; Parsons, Michael; Hogoncamp, Kristina; Alderman, Steven

    2007-01-01

    Available in abstract form only. Full text of publication follows: The most commonly identified threats to conventional glass fiber HEPA filter performance are moisture and rapid blinding of filters by smoke. Regenerable filter media composed of ceramics or sintered metal can be utilized as pre-filters to protect the more vulnerable glass fiber HEPA filters in the event of upset conditions. Additionally, used in a pre-filtering application, the use of these regenerable filters can potentially extend the lifetime of conventional units. A series of tests have been conducted using CeraMem ceramic membrane filters in an effort to evaluate their performance after repeated loading and air back pulse cleaning. This was done in an effort to access filter performance after repeated loading/cleaning cycles. The filters were loaded using a solid potassium chloride aerosol challenge. The filters were evaluated for pressure drop and filtering efficiency changes from one cleaning cycle to the next. Additionally, the particle size distribution of the aerosol penetrating the filters was measured. (authors)

  14. Further development of the cleanable steel HEPA filter, cost/benefit analysis, and comparison with competing technologies

    Bergman, W.; Lopez, R.; Wilson, K. [Lawrence Livermore National Lab., CA (United States)] [and others

    1997-08-01

    We have made further progress in developing a cleanable steel fiber HEPA filter. We fabricated a pleated cylindrical cartridge using commercially available steel fiber media that is made with 1 {mu}m stainless steel fibers and sintered into a sheet form. Test results at the Department of Energy (DOE) Filter Test Station at Oak Ridge show the prototype filter cartridge has 99.99% efficiency for 0.3 {mu}m dioctyl phthalate (DOP) aerosols and a pressure drop of 1.5 inches. Filter loading and cleaning tests using AC Fine dust showed the filter could be repeatedly cleaned using reverse air pulses. Our analysis of commercially optimized filters suggest that cleanable steel HEPA filters need to be made from steel fibers less than 1{mu}m, and preferably 0.5 {mu}m, to meet the standard HEPA filter requirements in production units. We have demonstrated that 0.5 {mu}m steel fibers can be produced using the fiber bundling and drawing process. The 0.5 {mu}m steel fibers are then sintered into small filter samples and tested for efficiency and pressure drop. Test results on the sample showed a penetration of 0.0015 % at 0.3 {mu}m and a pressure drop of 1.15 inches at 6.9 ft/min (3.5 cm/s) velocity. Based on these results, steel fiber media can easily meet the requirements of 0.03 % penetration and 1.0 inch of pressure drop by using less fibers in the media. A cost analysis of the cleanable steel HEPA filter shows that, although the steel HEPA filter costs much more than the standard glass fiber HEPA filter, it has the potential to be very cost effective because of the high disposal costs of contaminated HEPA filters. We estimate that the steel HEPA filter will save an average of $16,000 over its 30 year life. The additional savings from the clean-up costs resulting from ruptured glass HEPA filters during accidents was not included but makes the steel HEPA filter even more cost effective. 33 refs., 28 figs., 1 tab.

  15. Energy dissipation and high-strain rate dynamic response of E-glass fiber composites with anchored carbon nanotubes

    This study explores the mechanical properties of an E-glass fabric composite reinforced with anchored multi-walled carbon nanotubes (CNTs). The CNTs were grown on the E-glass fabric using a floating catalyst chemical vapor deposition procedure. The E-glass fabric with attached CNTs was then incorpor...

  16. A novel computer-aided method to fabricate a custom one-piece glass fiber dowel-and-core based on digitized impression and crown preparation data.

    Chen, Zhiyu; Li, Ya; Deng, Xuliang; Wang, Xinzhi

    2014-06-01

    Fiber-reinforced composite dowels have been widely used for their superior biomechanical properties; however, their preformed shape cannot fit irregularly shaped root canals. This study aimed to describe a novel computer-aided method to create a custom-made one-piece dowel-and-core based on the digitization of impressions and clinical standard crown preparations. A standard maxillary die stone model containing three prepared teeth each (maxillary lateral incisor, canine, premolar) requiring dowel restorations was made. It was then mounted on an average value articulator with the mandibular stone model to simulate natural occlusion. Impressions for each tooth were obtained using vinylpolysiloxane with a sectional dual-arch tray and digitized with an optical scanner. The dowel-and-core virtual model was created by slicing 3D dowel data from impression digitization with core data selected from a standard crown preparation database of 107 records collected from clinics and digitized. The position of the chosen digital core was manually regulated to coordinate with the adjacent teeth to fulfill the crown restorative requirements. Based on virtual models, one-piece custom dowel-and-cores for three experimental teeth were milled from a glass fiber block with computer-aided manufacturing techniques. Furthermore, two patients were treated to evaluate the practicality of this new method. The one-piece glass fiber dowel-and-core made for experimental teeth fulfilled the clinical requirements for dowel restorations. Moreover, two patients were treated to validate the technique. This novel computer-aided method to create a custom one-piece glass fiber dowel-and-core proved to be practical and efficient. © 2013 by the American College of Prosthodontists.

  17. Biomass-derived porous carbon modified glass fiber separator as polysulfide reservoir for Li-S batteries.

    Selvan, Ramakrishnan Kalai; Zhu, Pei; Yan, Chaoi; Zhu, Jiadeng; Dirican, Mahmut; Shanmugavani, A; Lee, Yun Sung; Zhang, Xiangwu

    2018-03-01

    Biomass-derived porous carbon has been considered as a promising sulfur host material for lithium-sulfur batteries because of its high conductive nature and large porosity. The present study explored biomass-derived porous carbon as polysulfide reservoir to modify the surface of glass fiber (GF) separator. Two different carbons were prepared from Oak Tree fruit shells by carbonization with and without KOH activation. The KOH activated porous carbon (AC) provides a much higher surface area (796 m 2  g -1 ) than pyrolized carbon (PC) (334 m 2  g -1 ). The R factor value, calculated from the X-ray diffraction pattern, revealed that the activated porous carbon contains more single-layer sheets with a lower degree of graphitization. Raman spectra also confirmed the presence of sp 3 -hybridized carbon in the activated carbon structure. The COH functional group was identified through X-ray photoelectron spectroscopy for the polysulfide capture. Simple and straightforward coating of biomass-derived porous carbon onto the GF separator led to an improved electrochemical performance in Li-S cells. The Li-S cell assembled with porous carbon modified GF separator (ACGF) demonstrated an initial capacity of 1324 mAh g -1 at 0.2 C, which was 875 mAh g -1 for uncoated GF separator (calculated based on the 2nd cycle). Charge transfer resistance (R ct ) values further confirmed the high ionic conductivity nature of porous carbon modified separators. Overall, the biomass-derived activated porous carbon can be considered as a promising alternative material for the polysulfide inhibition in Li-S batteries. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Measurement of Lung Cancer Tumor Markers in a Glass Wool Company Workers Exposed to Respirable Synthetic Vitreous Fiber and Dust

    Shabnam Abtahi

    2018-01-01

    Full Text Available Background: Occupational exposures to respirable synthetic vitreous fiber (SVF and dust are associated with many lung diseases including lung cancer. Low-dose computed tomography is used for screening patients who are highly suspicious of having lung carcinoma. However, it seems not to be cost-effective. Serum biomarkers could be a useful tool for the surveillance of occupational exposure, by providing the possibility of diagnosing lung cancer in its early stages. Objective: To determine if serum carcinoembryonic antigen (CEA and cytokeratin fragment (CYFRA 21-1 levels in workers exposed more than normal population to respirable SVF and dust may be used as indicators of progression towards lung cancer. Methods: An analytic cross-sectional study, including 145 personnel of a glass wool company, along with 25 age-matched healthy individuals, was conducted to investigate the relationship between occupational exposure to respirable SVFs and dust and serum levels of two lung/pleura serum tumor markers, CEA and CYFRA 21-1, measured by ELISA. Results: Individuals exposed to higher than the recommended levels of respirable SVF had higher serum concentrations of CEA and CYFRA 21-1, compared to controls (p=0.008 and 0.040, respectively, as well as in comparison to those exposed to lower than recommended OSHA levels (p=0.046 and 0.033, respectively. Workers with >9 years work experience, had significantly (p=0.045 higher levels of serum CYFRA 21-1 than those with ≤9 years of experience. Conclusion: It seems that working for >9 years in sites with detectable levels of respirable SVF and dust would increase the levels of known lung cancer serum tumor markers. Transferring these workers to sites with respirable SVF concentrations lower than the limit of detection in the air is recommended.

  19. Optimization of Process Parameters During Drilling of Glass-Fiber Polyester Reinforced Composites Using DOE and ANOVA

    N.S. Mohan

    2010-09-01

    Full Text Available Polymer-based composite material possesses superior properties such as high strength-to-weight ratio, stiffness-to-weight ratio and good corrosive resistance and therefore, is attractive for high performance applications such as in aerospace, defense and sport goods industries. Drilling is one of the indispensable methods for building products with composite panels. Surface quality and dimensional accuracy play an important role in the performance of a machined component. In machining processes, however, the quality of the component is greatly influenced by the cutting conditions, tool geometry, tool material, machining process, chip formation, work piece material, tool wear and vibration during cutting. Drilling tests were conducted on glass fiber reinforced plastic composite [GFRP] laminates using an instrumented CNC milling center. A series of experiments are conducted using TRIAC VMC CNC machining center to correlate the cutting parameters and material parameters on the cutting thrust, torque and surface roughness. The measured results were collected and analyzed with the help of the commercial software packages MINITAB14 and Taly Profile. The surface roughness of the drilled holes was measured using Rank Taylor Hobson Surtronic 3+ instrument. The method could be useful in predicting thrust, torque and surface roughness parameters as a function of process variables. The main objective is to optimize the process parameters to achieve low cutting thrust, torque and good surface roughness. From the analysis it is evident that among all the significant parameters, speed and drill size have significant influence cutting thrust and drill size and specimen thickness on the torque and surface roughness. It was also found that feed rate does not have significant influence on the characteristic output of the drilling process.

  20. Multidisciplinary Design Optimization for Glass-Fiber Epoxy-Matrix Composite 5 MW Horizontal-Axis Wind-Turbine Blades

    Grujicic, M.; Arakere, G.; Pandurangan, B.; Sellappan, V.; Vallejo, A.; Ozen, M.

    2010-11-01

    A multi-disciplinary design-optimization procedure has been introduced and used for the development of cost-effective glass-fiber reinforced epoxy-matrix composite 5 MW horizontal-axis wind-turbine (HAWT) blades. The turbine-blade cost-effectiveness has been defined using the cost of energy (CoE), i.e., a ratio of the three-blade HAWT rotor development/fabrication cost and the associated annual energy production. To assess the annual energy production as a function of the blade design and operating conditions, an aerodynamics-based computational analysis had to be employed. As far as the turbine blade cost is concerned, it is assessed for a given aerodynamic design by separately computing the blade mass and the associated blade-mass/size-dependent production cost. For each aerodynamic design analyzed, a structural finite element-based and a post-processing life-cycle assessment analyses were employed in order to determine a minimal blade mass which ensures that the functional requirements pertaining to the quasi-static strength of the blade, fatigue-controlled blade durability and blade stiffness are satisfied. To determine the turbine-blade production cost (for the currently prevailing fabrication process, the wet lay-up) available data regarding the industry manufacturing experience were combined with the attendant blade mass, surface area, and the duration of the assumed production run. The work clearly revealed the challenges associated with simultaneously satisfying the strength, durability and stiffness requirements while maintaining a high level of wind-energy capture efficiency and a lower production cost.