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1

Hong, Joohyun. "Structure-process-property relationships in polyester spun yarns : the role of fiber friction". Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/10118.

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2

Ramesh, Ram Kumar. "Solution-based formation of continuous SiC fibers". Thesis, Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/11130.

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3

Perkins, Cheryl Anne. "Physical characterization of meltblown fibers". Thesis, Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/10986.

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4

Zhang, Yi. "Solution studies on soybean protein for fiber spinning". Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/10287.

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5

Laton, Michael A. "Behavior of twisted fiber bundles under dynamic testing conditions". Thesis, Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/8586.

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6

Tshifularo, Cyrus Alushavhiwi. "Comparative performance of natural and synthetic fibre nonwoven geotextiles". Thesis, Nelson Mandela Metropolitan University, 2017. http://hdl.handle.net/10948/21362.

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The aim of this work was to establish a range of suitable process parameters which can be utilized to produce needlepunched nonwoven fabrics for geotextile applications. Nonwoven fabrics were produced from 100% PP, a blend of 50/50% PP/kenaf and 100% kenaf fibres. The depths of needle penetration of 4, 7 and 10 mm, stroke frequencies of 250, 350 and 450 strokes/min and mass per unit area of 300, 600 and 900 g/m2 were utilized for producing the fabrics, on a Dilo loom. The effect of depth of needle penetration, stroke frequency and mass per unit area on the fabric properties, namely, tensile strength, puncture resistance, pore size, water permeability and transmissivity were analysed. In addition, the effect of chemicals, namely, 10% ammonium hydroxide (NH4OH), 10% sodium chloride (NaCl) and 3% sulphuric acid (H2SO4) solutions on degradation of the fabric was also studied. The results have shown that density, thickness and nominal weight of the needlepunched nonwoven fabrics were related to each other and they were influenced by stroke frequency, depth of needle penetration and feed rate of the needlepunching process. The increase in nominal weight of the fabrics also increases thickness and density of the fabrics. The tensile strength and puncture resistance of the fabrics increased with the increases in stroke frequency, depth of needle penetration and fabric mass per unit area. However, lower tensile strength and puncture resistance were achieved in the fabrics produced at lower stroke frequency, lower depth of needle penetration and lower mass per unit area. Bigger pores were resulted in the fabrics produced at lower stroke frequency, lower depth of needle penetration and lower mass per unit area, however, pore size decreased with increases in stroke frequency, depth of needle penetration and mass per unit area. Water permeability depends on the pore size, properties of the fibres, stroke frequency, depth of needle penetration and mass per unit area. Higher tensile strength and higher puncture resistance were achieved in the needlepunched nonwoven fabrics produced from 100% PP fibres, therefore, they are suitable for some load-bearing geotextile applications, such as reinforcement and separation. However, higher water permeability was achieved in the fabrics produced from 100% kenaf fibres, therefore, they are ideal for geotextile applications where good water permeability is required. Higher values for transmissivity were obtained in the fabrics produced from a blend of 50/50% PP/kenaf fibres, therefore they are suitable for drainage applications. The fabrics produced from a blend of 50/50% PP/kenaf fibres achieved better values of tensile strength, puncture resistance, pore size and water permeability in comparison to that produced from 100% PP and 100% kenaf fibres. However, better tensile strength and puncture resistance were achieved in the fabrics produced from 100% PP fibres and bigger pore size and higher water permeability were achieved in the fabrics produced from 100% kenaf fibres. Therefore, it can be suggested that the nonwoven fabrics produced from a blend of 50/50% PP/kenaf fibres can fulfil almost all requirements of geotextile applications, such as, filtration, separation, reinforcement and drainage. The fabrics produced from 100% PP fibres were not damaged or deteriorated when treated with all the three chemicals due to chemical inertness of polypropylene. However, the fabrics produced from a blend of 50/50% PP/kenaf and 100% kenaf fibres were damaged and deteriorated when treated with H2SO4.
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7

Miller, Leah Margaret. "Characterization of extended chain polyethylene/S-2 glass, interply hybrid, fabric composites". Thesis, Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/8623.

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8

Yang, Fang. "Synthesis and characterization of star-like poly(p-hydroxybenzoic acid)-co-poly(m-hydroxybenzoic acid-co-poly(2-hydroxy-6-napthoic acid)". Thesis, Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/8711.

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9

Gilmore, Laurie Ann. "Chlorination of synthetic dyes and synthetic brighteners". Thesis, Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/20794.

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10

Reddy, Srinath. "Structure and properties of melt spun poly(4-methyl-1-pentene) fibers". Thesis, Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/10204.

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11

Musch, Janelle C. Riemersma. "Design optimization of sustainable panel systems using hybrid natural/synthetic fiber reinforced polymer composites". Diss., Connect to online resource - MSU authorized users, 2008.

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Thesis (M.S.)--Michigan State University. Dept. of Civil and Environmental Engineering, 2008.
Title from PDF t.p. (viewed on Aug. 3, 2009) Includes bibliographical references (p.129-132). Also issued in print.
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12

Kumar, Amit. "Application of near infrared reflectance spectroscopy to detection of heat set temperature of carpet yarn". Thesis, Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/8579.

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13

Natarajan, Subashree. "Characterization of poly(ethylene terephthalate) fibers using raman microscopy". Thesis, Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/8646.

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14

Seckin, M. Levent. "Effect of superba heatsetting on dyeing behavior of nylon 6,6 carpet yarns". Thesis, Georgia Institute of Technology, 1985. http://hdl.handle.net/1853/8268.

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15

Gupta, Murari Lal. "Development of commercial, sustainable processes for dyeing generic, unmodified polypropylene fiber". Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26643.

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Thesis (Ph.D)--Polymer, Textile and Fiber Engineering, Georgia Institute of Technology, 2009.
Committee Chair: Cook, Fred; Committee Member: Beckham, Haskell; Committee Member: Bottomley, Lawrence; Committee Member: Carr, Wallace; Committee Member: Etters, Nolan. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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16

LeBoeuf, Leighton Lee Jr. "Investigation of rabid low temperature depolymerization of polyethylene terephthalate : a novel approach". Thesis, Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/8588.

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17

Jacobs, Nokwindla Valencia. "Optimising the polymer solutions and process parameters in the electrospinning of Chitosan". Thesis, Nelson Mandela Metropolitan University, 2012. http://hdl.handle.net/10948/d1010762.

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Electrospinning is a technique, which can be used to produce nanofibrous materials by introducing electrostatic fields into the polymer solution. Due to their intrinsic properties, such as small fiber diameter, small pore size and large surface area, nanofibres are suitable for use in a variety of applications including wound dressing, filtration, composites and tissue engineering. The study demonstrates the successful and optimised production of Poly(ethylene oxide) (PEO) and chitosan nanofibres by electrospinning. The biocidal effects of chitosan, chitosan-silver nanofibres and silver nanoparticles were successfully investigated. To set up a functional electrospinning apparatus, the PEO solution parameters (concentration, molecular weight, solvent, and addition of polyelectrolyte) and applied potential voltage on the structural morphology and diameter of PEO nanofibres were studied. At lower PEO concentrations, the fibres had morphology with a large variation in fibre diameter, whereas at the higher concentrations, the nanofibres exhibited ordinary morphology with uniform but larger fibre diameters. Higher molecular weight showed larger average diameters when compared to that obtained with the same polymer but of a lower molecular weight. The addition of polyelectrolyte to the polymer solution had an influence on the structural morphology of the PEO. Flow simulation studies of an electrically charged polymer solution showed that an increase in the flow rate was associated with an increase in poly(allylamine hydrochloride) (PAH) concentration for the low molecular weight polymer, the shape and size of the Taylor cone increasing with an increase in PAH concentration for the low molecular weight polymer. During optimization of the PEO nanofibres, based on statistical modelling and using the Box and Behnken factorial design, the interaction effect between PAH concentration and the tip-to-collector distance played the most significant role in obtaining uniform diameter of nanofibres, followed by the interaction between the tip-to-collector distance and the applied voltage and lastly by the applied voltage. The production and optimization of chitosan nanofibres indicated that the interactions between electric field strength and the ratio of trifluoroacetic acid (TFA) and dichloromethane (DCM), TFA/DCM solvents as well as between electric field strength and chitosan concentration had the most significant effect, followed by the concentration of chitosan in terms of producing nanofibres with uniform diameters. Chitosan and chitosan-silver nanofibres could be successfully electrospun by controlling the solution properties, such as surface tension and electrical conductivity with the silver nanoparticles in the chitosan solutions affecting the electrospinnability. The silver nanoparticles in the chitosan solution modified the morphological characteristics of the electrospun nanofibres, while the conductivity and the surface tension were elevated. The fibre diameter of the chitosan and chitosan-silver nanoparticles decreased with an increase in the silver content. The electrospun chitosan nanofibres had a smooth surface and round shape as compared to the silver-chitosan nanofibres with a distorted morphology. The chitosan and chitosan-silver nanofibres as well as the silver nanoparticles exhibited antimicrobial or inhibition activity against S. aureus than against E. coli. S. aureus bacterial culture showed good cell adhesion and spreading inwards into the chitosan nanofibrous membrane. The chitosan-silver nanofibres exhibited a greater minimum inhibitory concentration (MIC), followed by silver nanoparticles and then chitosan nanofibres; suggesting a synergistic effect between the chitosan and silver nanoparticles.
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18

Gnesa, Eric Henry. "The conserved C-terminal domain of spider tubuliform spidroin 1 contributes to extensibility in synthetic fibers". Scholarly Commons, 2011. https://scholarlycommons.pacific.edu/uop_etds/771.

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Spider silk is renowned for its extraordinary mechanical properties, having a balance of high tensile strength and extensibility. To date, the majority of studies have focused on the production of dragline silks from synthetic spider silk gene products. Here we report the first mechanical analysis of synthetic egg case silk fibers spun from the Latrodectus hesperus tubuliform silk proteins, TuSp1 and ECP-2. We provide evidence that recombinant ECP-2 proteins can be spun into fibers that display mechanical properties similar to other synthetic spider silks. We also demonstrate that silks spun from recombinant thioredoxin-TuSp 1 fusion proteins that contain the conserved C-terminal domain exhibit increased extensibility and toughness when compared to the identical fibers spun from fusion proteins lacking the C-terminus. Mechanical analyses reveal that the properties of synthetic tubuliform silks can be modulated by altering the post-spin draw ratios of the fibers . Fibers subject to increased draw ratios showed elevated tensile strength and decreased extensibility, but maintained constant toughness. Wide-angle X-ray diffraction studies indicate that post-drawn fibers containing the Cterminal domain of TuSp 1 have more amorphous content when compared to fibers lacking the C-terminus. Taken together, these studies demonstrate that recombinant tubuliform spidroins that contain the conserved C-terminal domain with embedded protein tags can be effectively spun into fibers, resulting in similar tensile strength but increased extensibility relative to non-tagged recombinant dragline silk proteins spun from equivalently sized proteins.
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19

Li, Haiying. "A study on grafting poly(p-phenylene terephthalamide) with aliphatic amines and amides". Thesis, Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/8594.

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20

Lambert, Karen A. "Solution studies of soybean protein isolate using circular dichroism and SDS-PAGE". Thesis, Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/9495.

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21

Vohra, Sanjay. "A mechanics framework for modeling fiber deformation on draw rollers and freespans". Diss., Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-05172006-141347/.

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Thesis (Ph. D.)--Polymer, Textile & Fiber Engineering, Georgia Institute of Technology, 2007.
Karl I. Jacob, Committee Chair ; Youjiang Wang, Committee Member ; Mary Lynn Realff, Committee Member ; Arun Gokhale, Committee Member ; Rami Haj-Ali, Committee Member.
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22

Connor, Daniel Martin. "Design and synthesis of comonomers to enhance the optical, physical, and thermal properties of poly(ethylene terephthalate)". Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/29882.

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23

Kvaratskheliya, Varvara A. "A study of microstructural changes in synthetic fibres resulting from mechanical deformations". Thesis, De Montfort University, 2001. http://hdl.handle.net/2086/4906.

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This investigation examines the structure-property relationships of high modulus fibres. Five fibre classes were chosen for examination. These are p-aromatic copolyamide (Armos and SVM) and poly-p-aramids (Terlon and Kevlar) obtained from rigid chain polymers; poly-m-aramids (Phenylon and Nomex) obtained from semi rigid chain polymers, and aliphatic polyamide (Capron and Nylon) and Polyethylene obtained from flexible chain polymers. The thermo-mechanical properties studied include tensile properties, thermal shrinkage, creep-recovery, stress-relaxation and residual deformation over a range of temperatures. Results show that mechanical properties are highly related to chain rigidity, orientation and crystallinity of the fibres. The presence of aromatic rings in polymer chains increase the polymer rigidity. The higher the intermolecular attractive force and chain rigidity, the greater the resistance to heat. Study of the creep-recovery properties of polyamide fibres shows that irrecoverable residual deformation for the rigid chain polymers is accumulated within a very short initial period of time (15 seconds) when the load is applied. However for semi-rigid or flexible chain polymer fibres, the residual deformation is accumulated during the whole creep process. The characteristics of tensile stress-strain properties and the accumulation of residual deformation are found to be temperature dependent, especially in the case of Armos and SVM. The mechanical properties of polyamide fibres are also influenced by moisture which is associated with intermolecular interaction. Supplementary studies using FTIR, SEM and DSC were also undertaken. FTIR was used for preliminary investigation into the intermolecular hydrogen bonding and associated moisture in fibres. The results support the explanation of the thermomechanical properties of polyamide fibres. SEM results show the fibre rupture mechanism related to the fibre structures.
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24

Geurts, Paul. "The Synthetic spider silk fibers spun from Pyriform Spidroin 2, a glue silk protein discovered in orb-weaving spider attachment discs". Scholarly Commons, 2010. https://scholarlycommons.pacific.edu/uop_etds/759.

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Spider attachrnentdisc silk fibers are spun into a viscous liquid that rapidly solidifies, gluing dragline silk fibers to substrates for locomotion or web construction. Here we report the identification and artificial spinning of a novel attachment disc glue silk fibroin, Pyriform Spidroin 2 (PySp2), from the golden orb weaver Nephila c/avipes. MS studies support PySp2 is a constituent of the pyriform gland that is spun into attachment discs. Analysis of the PySp2 protein architecture reveals sequence divergence relative to the other silk family members, including the cob weaver glue silk fibroin PySpl. PySp2 contains internal block repeats that consist of two sub-repeat units: one dominated by Ser, Gin and Ala, the other Pro-rich. Artificial spinning of recombinant PySp2 truncations shows that the Ser-Gln-Ala-rich sub-repeat is sufficient for the assembly of polymeric subunits and subsequent fiber formation. These studies support that both orb- and cob-weaving spiders have evolved highly polar block-repeat sequence with the ability to self-assemble into fibers, suggesting a strategy to allow fiber fabrication in the liquid environment of the attachment discs.
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25

Thio, Beng Joo Reginald. "Characterization of bioparticulate adhesion to synthetic carpet polymers with atomic force microscopy". Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/31727.

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Thesis (Ph.D)--Chemical Engineering, Georgia Institute of Technology, 2009.
Committee Chair: J. Carson Meredith; Committee Member: Amyn Teja; Committee Member: F. Joseph Schork; Committee Member: Lawrence Bottomley; Committee Member: Mark Prausnitz. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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26

Thompson, Kimberlee Fay. "Modification of polymeric substrates using surface grafted nanoscaffolds". Diss., Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-05162005-165302/.

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Thesis (Ph. D.)--Polymer, Textile and Fiber Engineering, Georgia Institute of Technology, 2006.
Carter, W. Brent, Committee Member ; Cook, Fred, Committee Member ; Griffin, Anselm, Committee Member ; Michielsen, Stephen, Committee Chair ; Beckham, Haskell, Committee Member ; Bottomley, Lawrence, Committee Member.
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27

De, Bruin Riette. "Die versoenbaarheid van katoen/nylon- en katoen/poliester- skeringgebreide terriestofhanddoeke met industriele versorgingsprosedures". Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/16604.

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Thesis (MVerbruikerswet)--University of Stellenbosch, 2005.
ENGLISH ABSTRACT: The aim of the study was to investigate the compatibility of cotton/nylon and cotton/polyester warpknit terry towelling fabrics with industrial laundering procedures. The literature review focused, on the one hand, on the manufacture, finishing and structure of warp-knit terry towelling fabrics as well as on the physical structure, chemical nature and characteristics of the textile fibres used in the manufacturing of the towelling. On the other hand, a full exposition of the industrial laundering processes is provided, with specific reference to aspects that can have an effect on the towelling fabrics during the wash and tumble-drying cycles. Chapters Three and Four are reports on two research projects that can each be read independently. The aim of the first project was to determine the effect of industrial laundering procedures on the durability of cotton warp-knit terry towelling fabrics with a synthetic base structure. The tensile strength of cotton warp-knit terry towelling samples with a synthetic base structure was determined in the warp and weft directions and after 10, 20, 30, 40, and 50 wash cycles as well as wash and tumble-drying cycles. The tensile strengths in the warp direction of the washed terry towelling samples decreased significantly (p < 0.001) after 50 wash cycles. In contrast to this, the tensile strength in the weft direction increased, although not significantly (p > 0.05). As far as the comparison of the effect of industrial wash and wash and tumble-drying cycles is concerned, the tensile strengths in the warp direction of the towelling samples that were washed and washed/tumble-dried, were significantly lower (p < 0.001) after 20 and after 50 laundering cycles. As far as the tensile strengths in the weft direction were concerned, a similar pattern as with the wash and wash/tumble-drying processes, occurred. The tensile strengths initially increased and then gradually decreased. Furthermore, the tumble-drying process had greater damaging effects after 40 laundering cycles (p = 0.043) and especially after 50 laundering cycles (p < 0.0001). The aim of the second research project was to compare the durability of cotton warp-knit terry towelling fabrics with a nylon base structure with cotton warp-knit terry towelling fabrics with a polyester base structure after they had been subjected to industrial laundering processes. It was first established whether cotton/nylon and cotton/polyester warp-knit terry towelling fabrics are comparable. Secondly, the durability of cotton/nylon and cotton/polyester terry towelling fabrics was compared by determining the tensile strengths of the samples in the warp direction after they have been subjected to 50 industrial wash as well as wash and tumble-drying cycles. The two groups of untreated samples were regarded as similar on the basis of the percentage of fibre composition, knit fabric structure, knit density, mass and tensile strength. After 50 industrial wash cycles the tensile strengths of the cotton/nylon and cotton/polyester warp-knit terry towelling samples decreased significantly (p < 0.05). But there was no significant difference (p > 0.05) between the tensile strengths of the cotton/nylon and the cotton/polyester terry towelling samples after 50 washing cycles. There was a highly significant difference (p < 0.001) between the tensile strengths of the cotton/nylon and the cotton/polyester terry towelling samples after 50 wash and tumble-drying cycles. The tensile strength of the cotton/polyester terry towelling samples remained practically unchanged after the 50 wash/tumble-drying cycles, with the tensile strength of the cotton/nylon terry towelling samples decreased significantly (p < 0.001).
AFRIKAANSE OPSOMMING: Die doel van die studie was om ondersoek in te stel na die versoenbaarheid van katoen/nylon- en katoen/poliëster- skeringgebreide terriestofhanddoeke met industriële versorgingsprosedures. In die literatuuroorsig is daar enersyds gefokus op die vervaardiging, afwerking en struktuur van skeringgebreide terriehanddoekstowwe asook op die fisiese struktuur, chemiese aard en eienskappe van die tekstielvesels waarvan die handdoeke vervaardig is. Andersyds is ’n volledige uiteensetting van industriële versorgingsprosedures gegee, met spesifieke verwysing na aspekte wat tydens die was- en tuimeldrogingsiklusse ’n uitwerking op die handdoekstowwe kan hê. Hoofstukke drie en vier is opgeskryf as twee navorsingsprojekte wat elk ‘n geheel vorm. Die doel van die eerste projek was om die effek van industriële versorgingsprosedures op die duursaamheid van katoen skeringgebreide terriestofhanddoeke met ‘n sintetiese basisstruktuur te bepaal. Die breeksterkte van katoen skeringgebreide terriestofmonsters met ’n sintetiese basisstruktuur is in die skering- en inslagrigtings tydens en na afloop van 10, 20, 30, 40, en 50 was- asook was- en tuimeldrogingsiklusse bepaal. Die breeksterktes in die skeringrigting van die gewaste terriestofmonsters het betekenisvol afgeneem (p < 0.001) na 50 wassiklusse. In teenstelling hiermee het die breeksterktes in die inslagrigting toegeneem, hoewel nie betekenisvol nie (p > 0.05). Wat die vergelyking van die effek van industriële was- en was en tuimeldrogingsiklusse betref, is die breeksterktes in die skeringrigting van die handdoekmonsters wat gewas en gewas/getuimeldroog is, beduidend laer (p < 0.001) na 20 en na 50 versorgingsiklusse. Wat die breeksterktes in die inslagrigting betref het ‘n soortgelyke patroon by die was- en was/tuimeldrogingprosesse voorgekom. Die breeksterktes neem aanvanklik toe en daarna geleidelik af. Verder het die tuimeldrogingsproses na 40 versorgingsiklusse (p = 0.043) en veral na 50 versorgingsiklusse (p < 0.0001) ’n groter skadelike effek getoon. Die doel van die tweede navorsingsprojek was om die duursaamheid van katoen skeringgebreide terriestowwe met ’n nylon basisstruktuur te vergelyk met katoen skeringgebreide terriestowwe met ’n poliëster basisstruktuur nadat dit aan industriële versorgingsprosedures blootgestel is. Daar is eerstens vasgestel of katoen/nylon en katoen/poliëster terriehanddoekstowwe vergelykbaar is. Tweedens is die duursaamheid van katoen/nylon en katoen/poliëster terriestowwe vergelyk deur die breeksterktes van die monsters in die skeringrigting te bepaal nadat dit aan 50 industriële wasasook was- en tuimeldrogingsiklusse blootgestel is. Die twee groepe onbehandelde monsters is as soortgelyk beskou op grond van die persentasie veselsamestelling, breistofstruktuur, breidigtheid, massa en breeksterkte. Na 50 industriële wassiklusse het die breeksterktes van die katoen/nylon en katoen/poliëster skeringgebreide terriestofmonsters betekenisvol (p < 0.05) afgeneem. Daar was egter nie ’n betekenisvolle verskil (p > 0.05) tussen die breeksterktes van die katoen/nylon en katoen/poliëster terriestofmonsters na 50 wassiklusse nie. Daar was ’n hoogs betekenisvolle verskil (p < 0.001) tussen die breeksterktes van die katoen/nylon en katoen/poliëster terriestofmonsters na die 50 was/tuimeldrogingsiklusse. Die breeksterkte van die katoen/poliëster terriestofmonsters het na die 50 was/tuimeldrogingsiklusse feitlik onveranderd gebly terwyl die breeksterkte van die katoen/nylon terriestofmonsters hoogs betekenisvol (p < 0.001) afgeneem het.
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28

Modh, Haresh A. "Chemical treatment and adhesion in internally reinforced rayon fibers". Ohio : Ohio University, 1988. http://www.ohiolink.edu/etd/view.cgi?ohiou1182867766.

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29

Thio, Beng Joo Reginald. "Quantification of Bioparticulate Adhesion to Synthetic Carpet Polymers with Atomic Force Microscopy". Thesis, Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/14028.

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Atomic force microscopy (AFM) is adapted to the measurement of adhesion forces between indoor-air-pollutant bioparticulates and synthetic carpet fiber materials. This novel technology is used to characterize the adhesion and release of a model bioparticulate, the bacterium E. coli on Nylon. This knowledge will lead to expanded studies of a wider range of biocontaminants, and ultimately to the ability to design carpet and rugs upholstery that reduce the spread of indoor air pollutants. Such an advance would improve life significantly for the 20+ million Americans who suffer from asthma, and countless others who are afflicted with allergies and illness spread via bioparticulates.
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30

Giordano, João Batista. "Tratamento corona sobre superficies texteis". [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266145.

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Orientador: João Sinezio de Carvalho Campos
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
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Resumo: Dentre as técnicas de modificação de superfícies aplicadas na indústria para melhorar adesão, o tratamento por descarga corona é amplamente utilizado. Durante o tratamento por descarga coro na, espécies ativas são geradas, as quais podem reagir com a superfície do polímero ocasionando quebra de cadeias e formação de radicais, criando assim grupos polares na superfície e conseqüentemente, aumentando a sua energia superficial e propriedade de adesão. Neste trabalho utilizaram-se tecidos de poliéster e de algodão. Nos processos convencionais de preparação de tecidos são usados agentes químicos que agridem os efluentes têxteis, assim a descarga corona propõe-se como tratamento prévio do material sem ação de tais agentes, sendo tratamento único e apenas físico. Os objetivos deste trabalho são: 1. Tratar com descarga corona tecidos de poliéster e tecidos de algodão (engomado, lavado e desengomado); 2. Verificar hidrofilidade e absorção de corantes em tecidos de algodão tratados com descarga corona; 3. Verificar propriedades mecânicas em tecidos tratados com descarga corona. 4. Verificar a adesão de pigmentos em de tecidos de poliéster tratados com corona. Tecidos foram submetidos à descarga: corona variando-se o tempo exposição e altura entre os eletrodos, em seguida foi realizada testes de hídrofilidade, absorção de corante tipo reativo, adesão de pigmentos, solidez a lavagem e ensaios de resistência à tração e alongamento. Foi utilizada a técnica de microscopia óptica, ensaio de hidrofilidade para caracterizar os efeitos causados. Os resultados mostram que: houve aumento da hidrofilidade do tecido de algodão que de 50% em amostra sem tratamento passou até a 280% com o tratamento, observou-se também que com te~pos de 1 mino já ocorrem modificações nos tecidos quanto a hidrofilidade e absorção de corantes; houve aumento da absorção de corante nas regiões tratadas principalmente em processos contínuos de tingimento; ocorreu boa aderência de pigmentos em tecidos de poliéster tratados; não ocorrem alteração das propriedades mecânicas (resistência a tração e alongamento) nas amostras tratadas.
Abstract: Amongst the techniques of modification of surfaces applied in the industry to improve adhesion, the treatment for discharge corona widely is used. During the treatment for discharge corona, active species are generated, which can consequently react with the surface of polymer causing chain in addition and formation of radicals, thus creating polar groups in the surface and, increasing its superficial energy and property of adhesion. In this work they had been used weaveed of polyester and cotton. In the conventional processes of fabric preparation they are used chemical agents whom the effluent textile attack, thus the discharge corona is considered as previous treatment of the material without action of such agents, being treatment only e only physicist. The objectives of this work are: 1.To deal with discharge corona weaveed to polyester and fabrics cotton (starchy, washed and dissolved the gum); 2. To verify water absorption and absorption of corantes in fabrics of cotton treated with discharge corona; to 3.Verificar mechanical properties in fabrics dealt with discharge corona. 4. To verify the pigment adhesion in of treated polyester fabrics with corona. Fabrics had been submitted to the discharge corona varying the time exposition and height between the electrodes and, after that water absorption tests had been carried through, absorption of corante reactive type, pigment adhesion, solidity the laudering and assays of tensile strenght and allonge. The technique of optic microscopy was used, assay of water absorption to characterize the caused effect. The results show that: it had increase of the hidrofilidade of the cotton fabric that of 50% in sample without treatment passed until 280% with the treatment, was 9.lso observed that with times of 1 min. already the water absorption and absorption of corantes occur modifications in fabrics how much; it had increase of the absorption of corante in the regions treated mainly in continuous processes of dyeing good pigment tack occurred in treat polyester fabrics; they do not occur alteration of the mechanical properties (resistance the traction and allonge) in the treated samples.
Doutorado
Ciencia e Tecnologia de Materiais
Doutor em Engenharia Química
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31

Carvalho, José Geraldo de 1977. "Tratamentos térmico e corona em tecido de poliéster". [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266853.

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Orientador: João Sinézio de Carvalho Campos
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: O tratamento térmico, que na indústria têxtil é mais conhecido como termofixação, é um processo muito importante para garantir a estabilidade dimensional do tecido de poliéster durante os processos de beneficiamento e no uso. Mas o processo de termofixação modifica algumas propriedades do tecido e entre elas podemos destacar: Hidrofilidade, comportamento tintorial, alongamento e ruptura. Essas propriedades são influenciadas pelas variáveis tempo e temperatura de termofixação. Nesse sentido o presente trabalho tem como objetivo analisar as alterações proporcionadas pela termofixação nas propriedades físico-químicas do tecido de poliéster. O poliéster é um material que apresenta superfície quimicamente inerte, não porosa e com baixa energia de superfície (43 mN/m). O tratamento com descarga corona vem propor aumentar a energia de superfície, melhorar a hidrofilidade, o comportamento tintorial e a adesão do tecido termofixado e sem termofixar. Submeteram-se amostras de tecido plano de poliéster á termofixação em diversas combinações de tempo e temperatura dentro dos intervalos de 120 a 220°C e de 30 a 120 segundos. Após a termofixação mediu-se o encolhimento das amostras e submeteram-se as mesmas a testes de alongamento e ruptura. Trataram-se amostras de tecido de poliéster termofixadas e sem termofixar com descarga corona, e em seguida, submeteu-se as mesmas a testes de hidrofilidade, tingimento, estampagem, alongamento e ruptura. Observou-se que a termofixação promove encolhimento, aumento do alongamento, diminuição da hidrofilidade e da absorção de corante em tingimento de tecido de poliéster. O tratamento corona aumenta a hidrofilidade, a absorção de corante, a ancoragem de pigmentos em amostras de tecido de poliéster termofixadas e sem termofixar
Abstract: The thermal treatment, which in the textile industry is known as heat setting, is very important to ensure the dimensional stability of polyester fabric during the process of improving and use. But the process of heat setting changes some properties of the fabric and among them we can highlight: Hidrophilicity, dyeability, elongation and strength. These properties are influenced by variables dwell time and heat setting temperature. In that sense this work has as objective to analyze the changes caused by heat in the physico-chemical properties of polyester fabric. Polyester is a material that presents the surface chemically inert, non-porous and low surface energy (43 mN / m). The treatment with corona discharge is proposing to increase the surface energy, improve the hidrophilicity, dyeability and adhesion of the polyester fabric with and without heat setting. Samples of polyester plan fabric underwent to heat setting on various combinations of time and temperature within the interval between 120 to 220 ° C, from 30 to 120 seconds. After the heat setting was measured the shrinkage of the samples and underwent the samples by tests of elongation and rupture. Samples of polyester fabric with and without heat setting were treated with corona discharge and in sequence the samples were tested by hidrophilicity, dyeing and printing. The heat setting promotes shrinkage and increase the elongation of polyester fabric. It was observed that the heat setting promotes shrinkage, increase of elongation, reduction of hydrophilicity and reduction of uptake of dye in the dyeing of polyester fabric. The corona treatment increase the hydrophilicity, the absorption of dye in pad-thermofix process and the pigment anchoring in polyester fabric samples with and without heat setting
Mestrado
Ciencia e Tecnologia de Materiais
Mestre em Engenharia Química
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32

Li, Jian-xing. "Coupling agent effects on the interfacial adhesion in a sheath/core type bicomponent fiber". Ohio : Ohio University, 1989. http://www.ohiolink.edu/etd/view.cgi?ohiou1182441608.

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Guerra, Juan Rafael Filgueira. "Projeto de antena de microfita flexível utilizando de tecido malha a base de fibras naturais e sintéticas". Universidade Federal Rural do Semi-Árido, 2016. http://bdtd.ufersa.edu.br:80/tede/handle/tede/715.

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The flexible microstrip antennas are devices that guarantee the development of communications systems with greater adaptability to the different types of microwaves applications .The possibility of an antenna be designed using textile materials facilitates their conditioning on systems that need is in contact or very close to the human body. The mesh fabric offers greater adaptability to the application due its flexibility. To build the antenna, is necessary check the compatibility between the knitted fabrics available and project needs. Therefore, is essential study the behavior of the electrical and physical features of each structure, analyzing also the influence of synthetic and organic fibers in performance. The characterization allows choice which fabrics is better to manufacture the antenna, is designed and built one microstrip antenna with classic rectangular geometry using the knitted fabric with better performance. The synthetic fibers have better physical characteristics that improve the adaptability of the tissue as a substrate. The electrical characteristics of the mesh fabrics they presented similar behavior as the frequency variation. In the frequency 2.45 GHz knitted fabric composed of polyester and spandex has the best actual values of relative permittivity and loss tangent thus constructed is used in the antenna design. The results show that the resonance frequency is approximately 2.68 GHz, a variation near 230 MHz, this is due to aspects of the test antenna construction
As antenas de microfitas flexíveis são dispositivos que garantem o desenvolvimento de sistemas de comunicações com maior adaptabilidade aos diversos tipos de aplicações em microondas. A possibilidade de uma antena ser projetada utilizando materiais têxteis facilita seu condicionamento em sistemas que necessitem estar em contato ou muito próximo ao corpo humano. O tecido de malha oferece maior adaptabilidade à aplicação devido a sua flexibilidade. Com o objetivo de construir a antena, é necessário verificar a compatibilidade entre os tecidos de malha disponíveis e as necessidades do projeto. Assim, é indispensável estudar o comportamento das características elétricas e físicas de cada estrutura. Analisando também, a influência das fibras sintéticas e orgânicas no desempenho. A partir da caracterização e escolha dos tecidos que comporão a antena, é projetada e construída uma antena de microfita com geometria retangular clássica utilizando o tecido com melhor desempenho. Os tecidos que contém fibras sintéticas apresentam características físicas que aumentam a adaptabilidade do tecido como substrato. As características elétricas dos tecidos apresentam comportamento semelhante quanto à variação da frequência. Na frequência de 2,45 GHz o tecido de malha composto por Poliéster e Elastano apresenta os melhores valores de permissividade relativa real e tangente de perdas, assim, é utilizado no projeto da antena construída. Os resultados demonstram que a frequência de ressonância é aproximadamente 2,68 GHz, representando uma variação aproxima de 230 MHz, isso ocorre devido a aspectos ligados a fase de construção da antena teste
2017-05-24
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34

Sibellas, Aurélien. "Cordes textiles torsadées à fibres continues : Caractérisation de la structure et modélisation du comportement mécanique en extension". Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEI017.

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Les cordes textiles torsadées à fibres continues sont couramment utilisées en tant que renforts dans une grande variété d'applications industrielles et plus spécifiquement comme renforts dans le caoutchouc des pneumatiques. Les cordes concernées sont fabriquées à partir de fibres de nylon, de polyester ou d’aramide en les torsadant ensemble (de 200 à 1000 fibres de même matériau) pour obtenir ce qu’on appelle un surtors. L’assemblage de deux ou trois surtors en les torsadant ensemble permet de construire un retors qui sera dit hybride si les surtors initiaux sont composés de fibres différentes. L’ensemble des configurations donne une large gamme de propriétés mécaniques possibles impliquant à la fois les effets propres au comportement du matériau, à l’orientation locale des fibres ainsi qu’aux pressions transverses induisant des déséquilibres dans le cas de la présence de différentes natures de fibres. Cette thèse présente une étude structurelle précise des orientations de fibres par microtomographie aux rayons X dans les surtors et les retors ainsi qu’un outil original permettant d’analyser les fréquences spatiales caractéristiques des trajectoires de fibre. Un modèle mécanique de surtors en extension de la littérature est enrichi à partir de ces travaux appuyés d’une étude expérimentale supplémentaire de leur contraction latérale sous traction. L’influence du désordre du paquet de fibres initial sur le comportement mécanique du surtors final est analysée numériquement par la méthode des éléments finis en simulant le processus physique ayant lieu au cours de la prise de torsion. Enfin, un modèle mécanique général est proposé pour prédire le comportement mécanique en extension des retors hybrides constitué de trois surtors pouvant chacun afficher des torsions différentes entre elles
Twisted continuous filament yarns are commonly used as reinforcements in a wide variety of industrial applications and more specifically as reinforcements in tyre rubber. The yarns concerned are made of nylon, polyester or aramid fibres by twisting them together (from 200 to 1000 fibres of the same material) to obtain what is called a single yarn. The assembly of two or three single yarns by twisting them together makes it possible to build a multiply yarn that will be called hybrid if the initial single yarns are made of different fibres. All configurations give a wide range of possible mechanical properties involving the effects of the material's behaviour, the local orientation of the fibres and the transverse pressures inducing an imbalance in the case of the presence of different types of fibres. This thesis presents a precise structural study of fiber orientations by X-ray microtomography of single and multiply yarns and an original tool to analyze the spatial frequencies characteristic of fiber trajectories. A mechanical model of single yarn in extension from the literature is enriched from this work supported by an additional experimental study of their lateral contraction under extension. The influence of the disorder of the initial fibre bundle on the mechanical behaviour of the final single yarns is analysed numerically by the finite element method by simulating the physical process taking place during twisting. Finally, a general mechanical model is proposed to predict the mechanical behaviour in extension of the hybrid multiply yarns, consisting of three single yarns showing different torsions
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35

Léal, Françoise. "Etude de la production et de l'émanation de composés volatils malodorants sur textile à usage sportif". Thesis, Vandoeuvre-les-Nancy, INPL, 2011. http://www.theses.fr/2011INPL070N/document.

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Si la sueur fraîchement émise par le corps humain est inodore, la dégradation de celle-ci par la flore bactérienne cutanée produit des composés volatils malodorants, responsables des odeurs de transpiration. Les odeurs de transpiration apparaissent également sur les vêtements au cours de leur utilisation, particulièrement sur les textiles réalisés en fibres synthétiques. Ce travail a pour but d’améliorer la compréhension du phénomène d’émanation d’odeurs en étudiant l’effet du sujet testé, l’effet de la flore bactérienne et l’effet du textile sur les émissions de composés volatils malodorants.L’intérêt de ce travail réside dans l’approche globale de la problématique des odeurs de transpiration et dans la diversité des méthodes de mesure mises en place, tant dans l’étude de la flore microbiologique que dans les méthodes de mesures des composés odorants émis.Dans un premier temps, le dénombrement simultané de la flore bactérienne sur la peau et sur le vêtement a été réalisé sur un échantillon de 15 sujets à l’issue d’un exercice physique. Cette expérimentation a permis d’évaluer le taux de transfert bactérien moyen lors d’une activité sportive et d’étudier son rôle dans l’émission d’odeurs. Ensuite, afin d’affiner ces résultats, une méthode basée sur la biologie moléculaire a été mise en place pour réaliser le suivi qualitatif de la stabilité de la flore commensale axillaire d’un sujet pendant 3 mois. Le transfert bactérien spécifique entre la peau du testeur et le vêtement a été étudié pour 4 matières textiles sélectionnées (dont le coton et le PET). Ceci a permis de déterminer le rôle du transfert bactérien spécifique dans l’émission des odeurs à partir de textile.Enfin, le dernier chapitre est consacré à l’étude de l’émission de composés volatils et odorants à l’aide de mesures olfactives et d’un nez électronique au cours du temps par 8 composants textiles sélectionnés. Après traitement statistique par analyse en composante principale et étude détaillée des mesures, 9 composés chimiques ont été identifiés comme indicateurs d’un comportement textile malodorant. Ces derniers pourraient être utilisés dans la mise en place d’une méthode ciblée de mesure physico-chimique des mauvaises odeurs.Ce travail a permis de déterminer l’impact de chacun des facteurs sujet, flore bactérienne et textile dans l’émission d’odeurs. En outre, ce travail ouvre des perspectives sur l’étude des contaminations bactériennes par contact, mais également dans l’étude des odeurs, sur les phénomènes de désorption de molécules volatiles à partir de différentes matrices textiles et sur les solutions pouvant être envisagées pour limiter les émissions odorantes à partir de textiles
Fresh human sweat is odorless. Odoriferous volatile compounds are produced by the metabolism of bacteria living on the skin, generating strong malodor. Sweaty body odors do also appear on clothes during use, and especially on synthetic fabrics. The aim of this document is to improve understanding of odor emission by investigating subject effect, microbiota effect and fabric effect on the emission of odoriferous volatile compounds.Odors of perspiration are hereby globally approached with a wide use of methods and experimental devices, for microbial flora study as well as for odoriferous volatile compounds emission study.First, microflora enumeration has been simultaneously processed on the skin and on the fabric after exercise for 15 subjects. This experiment allowed an evaluation of the average bacterial transfer yield during physical activity and the beginning of the investigation of its effect on odor emission.A molecular biology methodology has then been developed in order to refine these results. Monitoring of qualitative composition of the microbiota has been performed to study the stability of the armpit’s ecosystem on a subject during 3 months. Specific microbial transfer from subject’s skin to clothe has been performed for 4 textile fabrics (including cotton and PET). This leaded to characterize the effect of specific bacterial transfer on odor emission from fabric.The last chapter is dedicated to the study of the emission of odoriferous volatile compounds over time using olfactory measurements and electronic nose for 8 selected fabrics. Principal component analysis targeted 9 chemical compounds that have been selected as malodorous behavior indicators for a given fabric. Those 9 compounds could be used for setting up a fitted physicochemical method of malodor.To conclude, this study helped to understand the effect of 3 factors in odor perception from a fabric after sport : subject, microbial flora and fabric. Perspectives have been charted on contact microbial contamination, but also on odor, and especially on desorption of odoriferous volatile molecules from a textile or knitted matrix. The solutions that could be used to limit malodorous emission from fabrics have also been discussed
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36

Mmelesi, Olga Kelebogile. "Synthesis and characterization of pine cone carbon supported iron oxide catalyst for dye and phenol degradation". Thesis, Vaal University of Technology, 2017. http://hdl.handle.net/10352/418.

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M. Tech. (Department of Chemical Engineering, Faculty of Engineering and Technology), Vaal University of Technology
Fenton oxidation is classified into two processes, homogeneous and heterogeneous. Homogeneous Fenton oxidation process, have been shown to be efficient in the degradation of organic pollutants. However, it was shown to have limitations which can be addressed by the heterogeneous Fenton oxidation. Despite the high efficiency of the heterogeneous Fenton oxidation process in the degradation of recalcitrant organic pollutants, the currents synthesis trends of the heterogeneous Fenton catalyst have been proven to be time and energy constraining, since it involves the multi-step were the activated carbon have to be prepared first then co-precipitate the iron oxide on the activated carbon. However, as much as the heterogeneous Fenton catalyst has been proven to have high catalytic activity towards degradation of organic pollutants, these catalysts have some limitations, such limitations include metal ions being leached from the catalyst support into the treated water causing catalyst deactivation and a secondary pollution to the treated water. In this thesis, these catalysts have been applied in the degradation of recalcitrant organic pollutants such as methylene blue and phenols. This study focuses on the single step synthesis of iron oxide nanoparticles supported on activated carbon, were carbonaceous material is impregnated with iron salt then pyrolysed via microwave heating. Microwave power and the amount of iron salt were optimized. The prepared activated carbon-iron oxide composites were applied to the degradation of 2-nitrophenol (2-NP) and methylene blue (MB). Methylene blue was used as a model compound due to the fact that it is easier to monitor the degradation process with UV-Vis as compared to 2-nitrophenol . 2-nitrophenol the additional step for the adjustment of pH is required since nitrophenols are colorless in color at lower pH. The characterization showed that the microwave power and the amount of the iron precursor have an influence on the porosity and surface functional groups of the activated carbon. Further it was vi observed that microwave power and iron precursor influnces the amount of iron oxide formed on the surface of the support. It was also observed that the activated carbon-iron oxide composite have the catalytic effects on the Fenton oxidation process of MB and 2-NP. The parameters such as H2O2, pH, catalyst dose, initial concentration, temperature affect the degradation of both MB and 2-NP. Kinetics studies showed that Fenton is a surface driven reaction since the results fitted the pseudo first order model. The thermodynamics parameters also showed that the reaction is endothermic, spontaneous and is randomized. This implies that the reaction of the degradation of MB and 2-NP is feasible and the catalysts prepared have high catalytic activity. MB and 2-NP were degraded to smaller organic molecules (carboxylic acids). The stability of the catalyst observed to decrease as the number of cycles increased, this is due to the leaching of iron ions from the support material. Hence it was concluded that the activated carbon-iron oxide composite was successfully synthesized and had the high catalytic activity for the degradation of MB and 2-NP.
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37

Beltran, Juan Felipe. "Computational modeling of synthetic-fiber ropes". Thesis, 2006. http://hdl.handle.net/2152/2678.

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Berry, Scott. "A characterization of micromanipulator controlled dry spinning of micro- and nanoscale polymer fibers". 2004. http://etd.louisville.edu/data/UofL0101t2004.pdf.

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Reichard, Eric Jonathan. "Chemometrics applied to the discrimination of synthetic fibers by microspectrophotometry". 2014. http://hdl.handle.net/1805/3795.

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Indiana University-Purdue University Indianapolis (IUPUI)
Microspectrophotometry is a quick, accurate, and reproducible method to compare colored fibers for forensic purposes. The use of chemometric techniques applied to spectroscopic data can provide valuable discriminatory information especially when looking at a complex dataset. Differentiating a group of samples by employing chemometric analysis increases the evidential value of fiber comparisons by decreasing the probability of false association. The aims of this research were to (1) evaluate the chemometric procedure on a data set consisting of blue acrylic fibers and (2) accurately discriminate between yellow polyester fibers with the same dye composition but different dye loadings along with introducing a multivariate calibration approach to determine the dye concentration of fibers. In the first study, background subtracted and normalized visible spectra from eleven blue acrylic exemplars dyed with varying compositions of dyes were discriminated from one another using agglomerative hierarchical clustering (AHC), principal component analysis (PCA), and discriminant analysis (DA). AHC and PCA results agreed showing similar spectra clustering close to one another. DA analysis indicated a total classification accuracy of approximately 93% with only two of the eleven exemplars confused with one another. This was expected because two exemplars consisted of the same dye compositions. An external validation of the data set was performed and showed consistent results, which validated the model produced from the training set. In the second study, background subtracted and normalized visible spectra from ten yellow polyester exemplars dyed with different concentrations of the same dye ranging from 0.1-3.5% (w/w), were analyzed by the same techniques. Three classes of fibers with a classification accuracy of approximately 96% were found representing low, medium, and high dye loadings. Exemplars with similar dye loadings were able to be readily discriminated in some cases based on a classification accuracy of 90% or higher and a receiver operating characteristic area under the curve score of 0.9 or greater. Calibration curves based upon a proximity matrix of dye loadings between 0.1-0.75% (w/w) were developed that provided better accuracy and precision to that of a traditional approach.
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