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1

Britz, Lizaan. "A comparison of the comfort properties, measured with a sweating manikin (WalterTM), of clothing containing different fibres." Thesis, Nelson Mandela Metropolitan University, 2017. http://hdl.handle.net/10948/14752.

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The main objective of the present study was to determine the relative role and importance of worsted suiting fabric fibre blend vis-à-vis fabric structural parameters, on the comfort related properties of 12 clothing ensembles, each comprising a different man’s suit, but the same wool/nylon underwear and cotton shirt. To achieve the objective, the comfort related properties, namely thermal resistance (Rt) and water vapour resistance (Ret) and water vapour permeability index (Im), of the clothing ensembles, as determined by means of WalterTM, a thermal sweating fabric manikin, were subjected to multi-linear and multi-quadratic analysis, as dependent variables, with the various suiting fabric parameters, namely weight, thickness, density, porosity, air permeability and wool content, as independent variables. It was found that the multi-quadratic regression analysis was able to best explain the observed differences in the clothing ensemble comfort related properties, in terms of the differences in suiting fabric properties. The regression analyses were used to isolate and quantify the effects of the various fabric and fibre content variables on the above mentioned comfort related properties of the various clothing ensembles. This study indicated that the suiting fabric structural properties (notably air permeability), had a more significant influence than either fibre blend or suiting fabric, as measured on WalterTM, a thermal sweating fabric manikin.
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2

Mtibe, Asanda, and Linda Linganiso. "Biocomposites from polyfurfuryl alcohol reinforced with microfibres and nanocellulose from flax fibres and maize stalks." Thesis, Nelson Mandela Metropolitan University, 2016. http://hdl.handle.net/10948/12175.

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This study is aimed at extracting cellulose and nanocelluloses (cellulose nanocrystals (CNCs) and cellulose nanofibres (CNFs)) from maize stalks and flax fibres. Both flax fibres and maize stalks are composed of cellulose, lignin, hemicellulose and extractives. The extraction of cellulose involves the removal of lignin, hemicellulose and extractives. The presence of these components in plant fibres hinders the extraction of cellulose and nanocelluloses. Prior to extraction of cellulose, the different concentrations (1 wt.%, 1.5 wt.% and 2 wt.%) of NaOH were optimised. However, chemical compositions and XRD results revealed that the treatment of flax fibres with 1.5 wt.% sodium hydroxide (NaOH) gives optimum results and this concentration was further selected for the extraction of cellulose. Cellulose was extracted by chemical treatments (sodium hydroxide (NaOH), sodium chlorite (NaClO2) and potassium hydroxide (KOH)) and a combination of chemical treatments and mechanical process (supermass colloider). The materials obtained after each treatment stage during the extraction process were characterised by different characterisation techniques such as Fourier transform infrared (FTIR) spectroscopy, environmental scanning electron microscopy (ESEM), X-ray diffraction (XRD) and thermogravimetric analysis (TGA). The results from the aforementioned characterisation techniques confirmed that cellulose was successfully extracted from flax fibres and maize stalks. Cellulose nanocrystals (CNCs) were extracted by sulphuric acid hydrolysis accompanied with ultra-sonication from cellulose obtained from flax fibres and maize stalks. The extracted CNCs were rod-like material with diameters and lengths in nanoscale and microscale, respectively. On the other hand, cellulose nanofibres (CNFs) were extracted by mechanical process (supermass colloider). The extracted CNFs were web-like material with diameters and lengths in nanoscale and microscale, respectively. The dimensions of nanocelluloses were measured by atomic force microscopy (AFM). Their dispersion was investigated by light polarised microscopy. The extracted nanocelluloses and cellulose were used to produce nanopapers and micropaper. Nanopapers mimic the traditional paper, the only difference of the nanopapers is that they are produced from high aspect ratio nanomaterials. Both nanopapers and micropapers were prepared by solvent evaporating method. Their thermal, optical and mechanical properties were investigated and compared. The mechanical and thermal properties of nanopapers produced from CNFs were better than those produced from CNCs and micropapers. On the other hand, nanopapers produced from CNCs were more transparent in comparison to nanopapers produced from CNFs and micropapers. Cellulosic fibres have attracted a considerable attention in composite materials due to their high tensile strength and tensile modulus. This study is focused on the development of biocomposites of polyfurfuryl alcohol (PFA) by in-situ polymerisation in the presence of acid catalyst (p-toluene sulphonic acid). Biocomposites were produced by reinforcing PFA with flax fibres (untreated and treated), nanoparticles and CNCs. The biocomposites reinforced with CNCs and flax fibres showed an improvement in mechanical, thermal and thermo-mechanical properties. On the other hand, biocomposites reinforced with nanoparticles obtained from treated maize stalks showed an improvement in mechanical and thermal properties while biocomposites reinforced with nanoparticles obtained from untreated maize stalks showed lower mechanical properties and decreased thermal stability.
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3

Srinivasan, K. "FDAS : a knowledge-based framework for analysis of defects in woven textile structures." Thesis, Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/8671.

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4

Manzlak, Derrick Anthony. "Boron Carbide Filled Neutron Shielding Textile Polymers." W&M ScholarWorks, 2007. https://scholarworks.wm.edu/etd/1539626861.

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5

KARNIK, POONAM PRAFULL. "USE OF CATIONIZED COTTON FOR TEXTILE EFFLUENT COLOR REDUCTION." NCSU, 2002. http://www.lib.ncsu.edu/theses/available/etd-20020301-132054.

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ABSTRACTKARNIK, POONAM. Use of Cationized Cotton for Textile Effluent Color Reduction.(Under the direction of Dr. Brent Smith and Dr. Peter Hauser) The liquid effluents from the textile industry mainly consist waters colored by thedyes used in the coloring of textile yarns and fabrics. These dyes can be removed by adsorption onto adsorbing materials like cotton. Waste cotton fibers can be cationized using a quaternary ammonium compound like 3-chloro-2-hydroxypropyltrimethylammonium chloride to their cationic form. This cationic form can be used as the adsorption medium for anionic dyes like acid, direct and fiber reactive dyes.

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6

Mittal, Khushboo Surender. "Development of Dual Functional Textile Materials Using Atmospheric Plasma Treatments." NCSU, 2009. http://www.lib.ncsu.edu/theses/available/etd-04092009-231813/.

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Glow discharges and low temperature plasmas and their applications have increasingly entered various areas of industrial applications. The textile industry is a developing area for application of atmospheric plasma techniques with significant growth potential. Technological advances made possible by plasma processes can reduce the costs for production by reduction in process times, improve the quality of product, generate products with new surface or bulk properties, and contribute to an environmentally sustainable work environment. A novel dual functional textile material was developed which possesses co-existing hydrophobicity and hydrophilicity on opposite faces utilizing atmospheric pressure plasma. One side of the substrate repels water whereas the other side absorbs water. The sequence and chemistry of the plasma aided side specific treatment of poly (ethylene terephthalate)/ polyurethane blend knitted fabric and cellulose with fluorocompound namely 1, 1, 2, 2- tetrahydroperfluorodecyl acrylate (70- 90%) and 1, 1, 2, 2- tetrahydroperfluorododecyl acrylate (10- 30%) was demonstrated to obtain the dual functionality. Effect of process and device parameters such as variation of (1) flow rate of monomer, (2) flow rate of helium and (3) flow rate of argon, (4) RF power, (5) time of plasma exposure to the fabric, (6) gap between electrodes, (7) prewashing the material before treatments and (8) preliminary plasma treatment on the fabric performance was also studied in this research.
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7

Bilgen, Mustafa. "Wrinkle Recovery for Cellulosic Fabric by Means of Ionic Crosslinking." NCSU, 2005. http://www.lib.ncsu.edu/theses/available/etd-04202005-140912/.

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When treated with formaldehyde-based crosslinkers, cellulosic fabrics show improved mechanical stability, wrinkle recovery angles and durable press performance, but N-methylol treatment also causes fabrics to lose strength and later to release formaldehyde, a known human carcinogen. We have discovered that ionic crosslinks can stabilize cellulose using high or low molecular weight ionic materials which do not release hazardous reactive chemicals, but at the same time provide improved wrinkle recovery angles as well as complete strength retention in treated goods. We have varied polyelectrolyte, the ionic content of fabrics, and various features of the application procedure to optimize the results and to develop an in-depth fundamental physical and chemical understanding of the stabilization mechanism.
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8

Horton, Aaron Michael. "Novel Reactive Dyes Based on Pyrimidine and Quinoxaline Systems." NCSU, 2009. http://www.lib.ncsu.edu/theses/available/etd-04302009-143537/.

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9

Goli, Kiran Kumar. "Use of Modified Cellulose for the Improvement of Water Repellency." NCSU, 2008. http://www.lib.ncsu.edu/theses/available/etd-06062008-145319/.

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A novel method is developed for imparting durable water repellency to cotton cellulosic fabrics based on ionic interactions. Most of the traditional water repellent finishing chemicals such as paraffin waxes, pyridinium compounds, formaldehyde based N-methylol crosslinkers, siloxanes and fluoro-carbon polymers are either non-durable to washing or environmentally unsafe or expensive. Our method includes cationization of cotton fabric with 3-chloro-2-hydroxypropyl trimethyl ammonium chloride (CHTAC) followed by subsequent treatment with a salt of stearic acid to form ionic attractions between cationic groups of cationized cotton fabric and anionic groups of stearate anion. These ionic interactions hold the stearate or hydrophobic molecules on the surface of cotton fabric outwards giving durable water repellency without releasing any hazardous chemicals present in almost all other durable water repellent treatments for textiles.
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10

Saunders, Joshua Daniel. "Novel Supramolecular Polyamides." NCSU, 2005. http://www.lib.ncsu.edu/theses/available/etd-07242005-213223/.

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The objective of this research is to use low DP poly(p-benzamide) (PBA) segments, terminated by units forming supramolecular bonds, able to extend the overall DP of the aromatic polyamide. PBA fibers, and the related industrially produced PPTA (Kevlar), exhibit their most interesting ultra-high strength properties only when a considerably large DP (>100) is attained. Use of cumbersome and expensive syntheses and solvents are required to attain DP in the range (~200-300) of industrial interest. Moreover, the fully covalent polymers thus far produced are highly insoluble in common organic solvents. On the other hand, easier processing becomes feasible if the DP of conventional PBA (prepared by the Yamazaki reaction) is increased by supramolecular bonding through ionic or hydrogen bond interactions. The effects of three different binding methods were first investigated on short rigid monomers with promising results the same binding was then used on rigid segments of PBA. The binding methods used two diamine binders triethylenediame (TED) and bipiperidine (Bipip) to form ionic bonds with the monomer, and polymer segments. The last method utilized a 2(6-iso cyanato hexylamino carbonyl amino)-6-methyl-4[1H]pyrimidinone (Upy) end group covalently bonded to the PBA polymer. This end group has the ability to form 4 hydrogen bonds with itself and thus could be used to increase the overall DP of the polymer starting material. This is believed to be the first recorded hydrogen bonded supramolecular interaction in amide type solvents. The novel and revolutionary idea of using low DP segments of PBA to increase the overall DP of polymer could be an industrially viable way to produce the highly sought after industrial polyamides.
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11

Lumley, Amy Catherine. "An Alternative Laundering Procedure to Predict the Durability of Flame Retardant Fabric." NCSU, 2003. http://www.lib.ncsu.edu/theses/available/etd-08192003-190154/.

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This project set out to determine an alternative laundering procedure to predict the durability of flame retardant fabrics while decreasing the overall cost and time involved for testing. Fabric was washed using conventional methods to be used as standards. These fabrics were characterized by burning characteristics, elemental analysis, fabric weight, percent weight change, shrinkage, color, and strength. Then fabrics were washed using an alternative method and characterized in the same manner. The alternative laundering procedure involved a programmable machine, Quickwash Plus. Parameters on the machine were varied to simulate x number of washings using a conventional industrial wash.
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12

Bridge, T. P. "Derivative spectroscopic studies on colourants used in textile technology." Thesis, Heriot-Watt University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356304.

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13

Mayfield, Angela Raye. "Characterization of textile materials by near-infrared relectance spectroscopy." Thesis, Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/8616.

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14

Horn, John Christopher. "Electrophoresis of reduced polypeptides dissolved from Lincoln wool and other animal fibres." Thesis, University of Leeds, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328302.

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15

Jaftha, Desiree Virginia. "South African National Accreditation System accreditation : a case study of a university of technology textile testing laboratory." Thesis, Cape Peninsula University of Technology, 2008. http://hdl.handle.net/20.500.11838/1222.

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Thesis (MTech (Quality))Cape Peninsula University of Technology, Cape Town, 2008.
The South African Government provides support to the clothing and textile industry by making funding available through programs in the Department of Science and Technology, such as the Tshumisano Technology Stations Program. The Technology Stations Program in particular supports a Technology Station in Clothing and Textiles (TSCT) at the Cape Peninsula University of Technology (CPUT), serving the needs for technology support and skills upgrading of the industry in the Western Cape, and in some instances, nationally. The TSCT testing laboratory provides testing services to small medium and large companies in South Africa at a reduced cost. The laboratory emphasises that customers should have fabrics tested before production commences. In this regard, the company will know the quality of the fabric or garment being purchased or manufactured. The laboratory technicians and assistants undergo a 'Woolworths' certification process on their test methods on an annual basis. The Woolworths certification is customer based. The laboratory is faced on a daily bases with the problem that more and more of their customers request that the facility should seek higher 'accreditation', as opposed to the current 'certification' it currently holds. The TSCT testing laboratory in addition has a responsibility to satisfy all of its customer certification and accreditation needs. Against this background, the management of the CPUT TSCT testing laboratory is now seeking accreditation from the South African National Accreditation System (SANAS) to widen the spectrum of its testing abilities. The primary research objectives of this dissertation are: To determine what the requirements are for SANAS accreditation by the CPUT TSCT testing laboratory. To determine if the CPUT TSCT testing laboratory is subject to a forced intervention for SANAS accreditation. To determine the criteria required for the CPUT TSCT testing laboratory accreditation. To determine the benefits that could be gleaned from this accreditation. To determine the effectiveness of the laboratory system, with regard to the fact that in addition to testing, the laboratory is used for teaching and learning. Descriptive research will serve as the research type, as it will describe an existing phenomena taking place. The research will be theoretical in nature and conducted in terms of both positivistic and phenomenological paradigms. Case study research will serve as research method. Data collection for the proposed research will be conducted using questionnaires. The CPUT Clothing and Textile Technology Department will serve as sampling frame, while the sample of respondents will be drawn on the basis of probability sampling. The sample will include lecturing staff, students, industry testing customers, textile test laboratory technicians, administration and support staff, all of whom are directly involved with the operation or make use of the laboratory facilities.
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16

Moyo, Doice. "Characterisation and optimisation of waterjet impact forces and energy parameters during hydroentanglement." Thesis, Nelson Mandela Metropolitan University, 2012. http://hdl.handle.net/10948/d1020134.

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Hydroentanglement is an important technique of bonding fibres to produce nonwovens using high velocity waterjets as the primary bonding tool. The work reported in this thesis addresses the gap in scientific knowledge and understanding, both theoretical and experimental, related to the impact forces and energy of the waterjets used in the hydroentanglement process. The current study focused on the impact forces and energy involved in, and the optimisation of, the hydroentanglement process. The results of the experimentally measured waterjet impact forces have been used to characterise the waterjets as well as to verify empirically the theoretical models currently available for explaining the mechanics of the hydroentanglement process. Since the process of supplying pressurised waterjets consumes a great deal of energy, the study of energy consumption and efficiency of the system has been critical. A method was proposed and used to determine the coefficients of velocity and water discharge of an industrial machine set-up, helping explain the mechanism of energy transfer during hydroentanglement and to concurrently optimise the process. Furthermore, a response surface experimental design was used to optimise the hydroentanglement of viscose and Polylactic acid (PLA) fibres into nonwovens. The selected Box-Behnken design, with four factors, namely the waterjet force, machine processing speed, input weight and fibre type, was employed to investigate the multivariate process factors and their interactive effects on physical and mechanical properties of nonwovens. Two sets of experiments, the later for validation, were performed to study the energy transfer efficiency. The results of the relative energy transfer to bond the fibrous web showed that it was possible to produce nonwovens using lower input energy without compromising the quality of the products. The optimum waterjet pressure and machine speed used to produce the Abstract nonwoven with the highest tensile strength for the least amount of energy supplied were identified.
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17

Pendergrass, Allan Douglas. "Process design and optimization in the bench scale production of silica fiber using the sol-gel method." Thesis, Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/8239.

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18

Jain, Mukesh Kumar. "Physical and morphological changes during the conversion of acrylonitrile-based precursors to carbon fibers by Mukesh Kumar Jain." Diss., Georgia Institute of Technology, 1985. http://hdl.handle.net/1853/8556.

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19

Qian, Li-Ren. "Characterization of polyethylene terephthalate heat set carpet yarn by near infrared reflectance spectroscopy." Thesis, Georgia Institute of Technology, 1987. http://hdl.handle.net/1853/9208.

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20

Bhat, Gajanan S. "Stabilization of pan-based precursors for carbon fibers by Gajanan S. Bhat." Diss., Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/10119.

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21

Caldas, Victor. "Morphology, physical and tensile properties of quench-cooled isotactic polypropylene films and spunbonded fabrics." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40026.

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The room temperature morphology of quench-cooled isotactic polypropylene (iPP) films and its development were investigated by scanning transmittance electron microscopy (STEM) and differential scanning calorimetry (DSC). STEM dark field images revealed that within an amorphous matrix there exist microcrystalline regions, 160 A in size on the average, having the $ alpha$-monoclinic crystal form. Regions of lower crystalline order were also observed which have an $ alpha$-monoclinic crystal form that has a substantially longer b crystallographic axis. DSC studies indicate that during quench-cooling to the glassy state iPP samples attain a low degree of crystalline order to an extent that depends on sample mass. Upon heating from the glassy state, an exothermic transition is observed following the glass transition temperature which corresponds to the formation of the room temperature morphology.
Cross polarization/magic angle spinning (CP/MAS) nuclear magnetic resonance (NMR) spectroscopy was used to monitor morphological changes in the purely crystalline phase of quench-cooled iPP films and spunbonded fabrics during annealing. The spectra were obtained using a pulse sequence that incorporates a delay period with a reduced spin locking field prior to cross polarization. Morphological changes occurring within the purely crystalline phase of iPP were related to observations made by DSC. Upon annealing, the CP/MAS NMR spectrum of the purely crystalline phase of both iPP samples changed by a redistribution in the intensity of the various peaks within a given carbon resonance. This redistribution of intensity was found to reflect the conversion from the $ alpha sb1$ to the $ alpha sb2$ monoclinic crystal forms. It is shown that the double melting endotherm observed by DSC for the spunbonded fabrics is due to the exothermicity which is associated with this conversion. It is concentrated in the temperature region between 156 and 163$ sp circ$C.
The tensile properties of the spunbonded iPP fabrics and fibers were enhanced by the dispersion of a silica/silicone additive and by changing the resin characteristics. This additive acts as a nucleating agent for iPP under isothermal crystallization conditions. This nucleating ability manifests itself in smaller crystal sizes and higher nucleation densities in the iPP fibers and bond points. The improved tensile properties are attributed to the smaller crystal sizes which form a more homogeneously dispersed crystalline phase in the amorphous phase as well as to increase the number of load-bearing tie molecules.
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22

Cruthers, Natasha Marie, and n/a. "Textile fibre from six cultivars of harakeke (Phormium tenax)." University of Otago. Department of Clothing and Textile Sciences, 2005. http://adt.otago.ac.nz./public/adt-NZDU20070501.135549.

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The object of this study was to identify microscopic differences among six selected cultivars of harakeke traditionally used by Maori in weaving. The cultivars were Arawa, Makaweroa, Paretaniwha, Takaiapu, Takirikau, and Tapamangu. The effectiveness of different microscopy techniques for taking measurements of the dimensions of ultimate fibres using a factorial experimental design was investigated in part A. Constant variables were geographical location, location of specimens along the leaf, season (winter), individual plant, fan, north-facing fan, and age of plant (approximately seven years), and cultivars (Paretaniwha and Tapamangu). Experimental variables were the microscopy techniques used and measurement axis. Techniques selected use on further cultivars in part B were transverse sections of leaf specimens 4 m thick, embedded in Paraplast� and observed using LM, and non-fixed ultimate fibres observed using SEM. In part B the dimensions of ultimate fibres from the six selected cultivars of harakeke were measured, and analysed (ANOVA and Tukey's HSD), and the transverse section shapes of fibre aggregates were observed. Transverse widths of ultimate fibres ranged from 10.15 m (Takaipu) -12.80 m (Paretaniwha). Ultimate fibre lengths ranged from 3735 m (Takirikau) - 4751 m (Makaweroa). The cultivars prizes for muka, Arawa and Makaweroa, had the longest and finest ultimate fibre bundles more uniform in transverse-sectional shape than the other cultivars studied and perhaps this explains their selection for extraction of muka. Takirikau had a high yield of ultimate fibre bundles, and perhaps this makes extraction of muka worthwhile. Paretaniwha differed from the other five cultivars studied having an average number of ultimate fibre bundles per unit width that were narrow and non-uniform in shape, and composed of short, thick, ultimate fibre cells. The microscopic structure of muka from six selected cultivars of harakeke used traditionally for weaving varied and may explain differences perceived by weavers, and that different end uses are preferred for various cultivars.
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23

Morali, Eyup Kaan. "Ozonation Of A Denim Producing Textile Industry Wastewater." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612428/index.pdf.

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Denim production is one of the leading sub-sectors of textile industry which basically generates highly colored indigo dyeing effluents. In the present study, ozonation was applied to the indigo-dyeing effluent(COD=820 mg/L
color=5500 Pt-Co), and to the whole effluent from a denim-producing plant before(COD=2750 mg/L
color=3950 Pt-Co) and after(COD=800 mg/L,color=3700 Pt-Co) biological treatment for degradation/detoxification purposes. Ozonation was also tried in the wastewater of the plant(COD=3100 mg/L
color=4500 Pt-Co) that would be produced after some foreseen cleaner production measures
caustic recovery and reusing of dyeing process wastewater. When applied to indigo-dyeing wastewater
ozonation provided 95% color and 61% COD removals at 1320 mg/h ozone dose within 60 minutes The optimum pH was evaluated as 4 when indigo-dyeing wastewater exposed to ozonation at different pHs(1.6-12.3). On the other side, ozonation applied as pre-treatment to the plant effluent provided 86% color and 46% COD removals with 3240 mg/h ozone dose in 70 minutes. Less satisfactory results were obtained when ozonation was tried in the wastewater after measures, with 86% color and 31% COD removals at 3960 mg/h ozone dose in 80 minutes. When applied to the biologically-treated effluent
at 420 mg/h ozone dose and within 40 minutes, ozonation removed 47% of influent COD and 96% of influent color indicating better performance of ozonation in postoxidation. In order to assess possible improvements on ozonation with the addition of H2O2, different concentrations were tried, but no significant improvement was obtained. The improvement in BOD5/COD index was also determined for the ozonetreated plant effluent to measure the effects of ozonation on biodegradability and found out that BOD5/COD ratio has improved to 0.39 from 0.22.
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24

Chapple, Stephen Anthony. "Improving certain high performance properties of natural fibres." Thesis, Nelson Mandela Metropolitan University, 2007. http://hdl.handle.net/10948/815.

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Cotton possesses many characteristics that make it desirable to the consumer, and this has resulted in its usage in a broad range of products. Cotton, however, is a flammable material that is easily ignited and rapidly consumed. The flame retardant treatment of cotton is, therefore, an important textile process that has received wide attention over many years. There are a number of commercial flame retardant treatments available for cotton, the most common being phosphate-based. These treatments, however, often have drawbacks or have a negative impact on the desirable properties of the fibre and the challenge still exists for designing better flame retardant products and systems that are durable and have limited impact on fibre properties. The study considers the application of the sol-gel as a coating on fabric that was pre-treated with a phosphate-based flame retardant or as a means for applying a phosphate-based flame retardant. Both treatment methods were found to be suitable for imparting flame resistance to the fabric. The effect of various phosphate-based flame retardants on flammability and fabric properties such as colour, handle and strength was investigated and it was shown that a diammonium phosphate and urea combination gave the best flame resistance. In this regard, a flame resistance was achieved with a lower amount of phosphorous than was used in similar conventional treatments. The durability of the coating to rinsing with water and soaping with a detergent was also investigated. It was found that the flame resistance was lost after rinsing or soaping but the prevention of afterglow combustion was retained. It was shown that the preparatory treatment of the fabric influenced the sol-gel coating process and the flammability of the fabric. Mercerisation and bleaching of the fabric increased the “wet pick-up” during the coating process and improved the flame resistance. The influence of various factors was also investigated in further detail. The ratio of the sol-gel components, the delay after coating prior to drying (hang time) and the curing time were investigated using an experimental design. The curing time and the ratio of components in the sol-gel were shown to have the greatest influence on fabric properties and fabric flammability. It was shown that there is a trade-off between the desired high level of fabric flame resistance and preserving the inherent properties of the fabric such as colour, handle and strength.
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25

Jinks, Douglas David. "Drying of latex backcoated acrylic fabrics: optimization and control." Thesis, Georgia Institute of Technology, 1985. http://hdl.handle.net/1853/11242.

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26

Vargantwar, Pruthesh Hariharrao. "Preparation of ionic cellulose for wrinkle resistant fabrics." NCSU, 2007. http://www.lib.ncsu.edu/theses/available/etd-04252007-154942/.

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Conventional treatment of cellulosic fabrics by formaldehyde-based cross-linkers provides improved wrinkle recovery angles (WRA) and durable press (DP) performance. But these treatments suffer from strength loss and later release of formaldehyde, a known carcinogen. Ionic crosslinking offers a potential solution to these problems, and has shown improved wrinkle recovery performance in previous studies. In the current novel method of ionic crosslinking for wrinkle resistant fabrics, the cellulosic fabric is treated with salt of mono chloroacetic acid and 3-chloro-2-hydroxypropyl trimethyl ammonium chloride (CHTAC) sequentially or in mixture to form covalently bonded anionic and cationic sites on cellulose, which are durable to washing, and which form inter/intra molecular ionic cross-links. There is no later release of hazardous chemicals involved with this treatment and improved wet WRA are obtained. Fabric treated by this method gained tensile strength and breaking strain compared to the untreated fabric. Different routes for chloroacetate treatment are presented. Pad-dry-pad-cure is the most efficient route and a functional relationship between the anionic content and the process parameters is established. Analytical techniques like confocal microscopy and scanning electron microscopy are used to confirm the morphological changes and occurrence of carboxymethylation reaction in the fiber interior.
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27

Zhang, Shu. "Mechanical and physical properties of electrospun nanofibers." NCSU, 2009. http://www.lib.ncsu.edu/theses/available/etd-07102009-165411/.

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The process of electrospinning was utilized to fabricate randomly aigned nylon6 nanofibers and aligned nylon6 nanofibers. Polymer concentration affecting electrospinning was investigated. This parameter was evaluated using degree of crystallinity by differential scanning calorimetry (DSC) as well as visual images produced by scanning electron microscopy (SEM). DSC data demonstrated that more crystals were formed with lower polymer concentrations; SEM images revealed that slimmer fibers were produced by lower concentrations. The mechanical properties of unoriented fibers and aligned fibers were tested on Instron 5544. The result of tensile tests indicated higher Youngâs modulus and tensile strength of aligned nanofibers than that of unaligned fibers. The SEM images at broken edges of fibers illustrated different broken mechanisms of these two forms of nanofibers. The broken mechanism of aligned nanofibers was further confirmed by crystallinity parameters obtained from DSC and fiber diameter shown from SEM images.
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28

Rex, Matthew. "ROOM TEMPERATURE FLUORESCENCE SPECTROSCOPY AS A TOOL FOR THE FORENSIC TRACE ANALYSIS OF TEXTILE FIBERS." Doctoral diss., University of Central Florida, 2009. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4355.

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ABSTRACT Trace textile fiber evidence is found at numerous crime scenes and plays an important role in linking a suspect to the respective scene. Several methods currently exist for the analysis of trace fiber evidence. Microscopy provides information regarding the fibers material, color and weave. For more detailed chemical analysis chromatographic methods are employed and for discrimination between dyes, liquid chromatography coupled with mass spectrometry (LC-MS) is currently the method providing the most discrimination. These methods have primarily focused on the dyes used to color the fibers and have not investigated other components that can potentially discriminate among fibers. This dissertation deals with investigations into the fluorescence of the fiber dyes, (contaminants?) and the fibers themselves, as well as methodology for discriminating between fibers using fluorescence. Initial systematic analysis was conducted on dye standards and extracts taken from fibers colored with the respective dyes of interest. Absorbance, excitation and fluorescence spectra were compared between standards and extracts to determine the optimal area of the fiber to investigate: dyes, fluorescent impurities or the whole fiber. High performance liquid chromatography investigations were performed to give detailed information on the number of dye and fluorescent components present in extracts. Our investigations then focused on the best room-temperature fluorescence (RTF) data format for analysis and discrimination of fiber samples. An excitation emission matrix (EEM) was found to give the greatest amount of spectral information and provide the highest level of discrimination. Successful discrimination between non similar and similar fibers was achieved with the aid of Chemometric analysis. The level of discrimination obtained via RTF-EEM spectroscopy was sufficient to differentiate among fibers obtained from two separate cloths of the same material and colored with the same dye reagent. Final studies deal with examining exposure of the fiber to various environmental contaminants. Clothing fibers are typically exposed to myriad numbers of contaminants, from food stains to cigarette smoke. The challenge then becomes detecting fluorescence signals from trace amounts of these environmental contaminants. We demonstrate the detection and classification of polycyclic aromatic hyrdrocarbons (PAH) present on fibers after exposure to cigarette smoke. This dissertation also investigates the change in fluorescence emission after laundering fibers numerous times. The main drawback of chemical analysis of fibers is the destructive nature of the methods. To extract a dye or contaminant from a fiber essentially destroys the evidence. This leaves the investigator without their original sample in the courtroom. This also provides a finite amount of sample for testing and analysis. This is true of chromatographic methods and for the method detailed in this dissertation which makes use of extracts taken from fiber samples. Lastly, we propose an instrumental setup coupling a microscope to a spectrofluorimeter for the purpose of taking EEM directly from a fiber sample. This setup makes use of the superior optics of the microscope for focusing excitation light onto the fiber sample. Initial studies have been performed on extracts from a single textile fiber and EEM collected from said fiber.
Ph.D.
Department of Chemistry
Sciences
Chemistry PhD
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29

Wong, Ka Chun. "Focused Ion Beam Nanomachining of Thermoplastic Polymers." Thesis, North Carolina State University, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3538536.

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Commercially available Ga+ focused ion beam (FIB) instruments with nanometer size probe allows for in situ materials removal (sputtering) and addition (deposition) on a wide range of material. These spatially precise processes have enabled a wide range of nanofacbrication operations (e.g. specimen preparation for analysis by scanning electron microscope, transmission electron microscope, and secondary ion mass spectrometer). While there exists an established knowledge of FIB methods for sample preparation of hard materials, but FIB methodology remain underdeveloped for soft materials such as biological and polymeric materials.

As FIB is increasingly utilized for specimen preparation of polymeric materials, it is becoming necessary to formulate an information base that will allow established FIB techniques to be generalized to this spectrum of materials. A thorough understanding of the fundamental ion-solid interactions that govern the milling process can be instrumental. Therefore, in an effort to make the existing procedures more universally applicable, the interrelationships between target material, variable processing parameters, and process efficiency of the milling phenomena are examined. The roles of beam current, distance (i.e. step size) between successive FIB beam dwell and the time it spent at each dwell point (i.e. pixel dwell time) are considered as applied to FIB nanomachining of four different thermoplastic polymers: 1. low density polyethylene (LDPE), 2. high density polyethylene (HDPE), 3. Polystyrene (PS), and 4. nylon 6 (PA6). Careful characterization of such relationships is used to explain observed phenomena and predict expected milling behaviors, thus allowing the FIB to be used more efficiently with reproducible results. Applications involving different types of polymer composite fiber are presented.

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Lutseke, Nothando Sazikazi. "An investigation into the properties of cotton fibres as used in nonwoven fabrics." Thesis, Rhodes University, 1989. http://hdl.handle.net/10962/d1018241.

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The purpose of this investigation was to determine the properties that characterise cotton fibres in the various stages in the CPNF process as well as to determine which fibre characteristics a r e required to entangle the fibres to produce a successful CPNF . The criteria adopted in this work for a successful CPNF include: 1. the tensile strength of the fabrics 2. a well-defined pattern 3. absorbency and wicking The properties selected for investigation were 1. the cotton fibre surface (using SEM and DSC analyses) 2. the degree of degradation of the cotton fibre as a result of the CPNF process (using cellulose fluidity measurements) 3. the non-cellulosic content of the fibre (using IR, DSC, and Chemical analyses) 4. fibre friction 5. absorbency and wicking 6. tensile properties Analysis of the results indicates clearly what the fundamental properties of the cotton fibre must be for a successful cotton CPNF to be manufactured. The conclusions also indicate the necessary properties a man-made fibre must have to produce a successful CPNF.
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31

Orpiszak, Martin. "Oxidation of cellulose to favour its dissolution in alkaline aqueous solution before regeneration into textile yarn." Thesis, KTH, Kemiteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-296556.

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Detta examensarbete är en del av CelluFil-projektet och syftar till att optimera förhållandena för upplösning av cellulosa i vattenlösning av natriumhydroxid följd av regenering i form av ett garn. Tidigare arbeten har visa tatt cellulosa kan lösas i vattenlösning vid -10°C, men sådana förhållanden är inte tillämpliga i industriell skala. Målet med detta projekt är att arbeta vid rumstemperatur.  För detta kommer karboxylgrupper att införas i cellulosakedjorna för att öka cellulosans lighet i ett alkaliskt vattenbaserat medium. Därefter kommer cellulosan att fällas ut igen i en sur lösning. Natriumperjodat gör det möjligt att oxidera alkoholgrupperna i cellulosakedjan på C2- och C3- positionerna genom att öppna glukosenheterna för att skapa två karbonylfunktioner (aldehyde) som sedan lätt kan oxideras till karboxylgrupper med överoxidering med natriumklorit.  Den första delen av rapporten är tillägnad litteraturöversikten om ämnet med focus på natriumperjodat oxidation. Därefter föreslås ett allmänt protokoll från natriumperjodat oxidation till regenering av cellulosa till garn i en svavelsyralösning. Flera förhållanden för natriumperjodat oxidationen testas vid olika temperaturer, med eller utan metallsalter och med olika oxidationsdoser.  Upplösningsutbytet är direkt kopplat till karboxylinnehållet infört i cellulosakedjorna. Periodatoxidationen leder också till minskningen av polymerisationsgraden men cellulosas DPv förblir tillräckligt hög med det riktade COOH-innehållet och för textilapplikationer. Den möjliga produktionen av hydroxylradikaler under natriumperjodat oxidationen har undersökts med EPR/Spin-trapping. Endast försök gjorda med UV-strålning visade OH°. Således förklaras fortfarande inte depolymerisationen av cellulosa under perjodat oxidation framställd under mörka förhållanden. Eftersom, konsumtion av natriumperjodat är låg under oxidationen är dess återvinning en nyckelfråga för en industriell applikation. Det har visat sig att oxidationsfiltraten kan återanvändas flera gånger före total konsumtion av periodat. Kvaliteten på celluloser oxiderade med återvunna filtrat, särskilt deras upplösningsförmåga, bör kontrolleras.
This master thesis is part of the Cellufil Project and aims to optimize the conditions for dissolving cellulose in aqueous sodium hydroxide solution followed by regeneration it in the form of a yarn. Previous works have shown that cellulose could be dissolved in soda at -10°C, but such conditions are not applicable at industrial scale. The objective of the present project is to work at room temperature.  For that, carboxyl groups will be introduced in the cellulose chains in order to increase cellulose solubility in an alkaline aqueous medium, after this it is reprecipitated it in acidic solutions. Periodate makes it possible to oxidize the alcohol groups of cellulose on C2 and C3 positions by opening the glucose units to create two carbonyls functions (aldehyde) which can then be easily oxidized into carboxylic groups with overoxidation using sodium chlorite. A first part of the report is dedicated to the literature review on the subject, focusing on periodate oxidation. Then, a general protocol is proposed from the periodate oxidation to the regeneration of cellulose into yarn in sulfuric acid solutions. Several conditions for the periodate oxidation are tested, at different temperatures, with or without metal salts and with different oxidant dosages.  The dissolution yield is directly linked to the carboxyl content introduced in the cellulose chains. The periodate oxidation also leads to the decrease of the cellulose degree of polymerization but cellulose DPv still remains sufficiently high in the case of the targeted COOH contents and for textile applications. The possible production of hydroxyl radicals during the periodate oxidation has been investigated by EPR/Spin-trapping. Only trials made with UV radiations showed OH°. Thus, cellulose depolymerization during periodate oxidation made in dark conditions is still not explained. Because the periodate consumption is low during the oxidation, its recycling is a key issue for an industrial application. It has been shown that the oxidation filtrates could be reused several times before total oxidant consumption. The quality of celluloses oxidized with recycled filtrates, especially their dissolving ability, should be checked.
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32

Baldia, Christel M. "Development of a protocol to detect and classify colorants in archaeological textiles and its application to selected prehistoric textiles from Seip Mound in Ohio." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1122567876.

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33

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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34

Michel, Davina. "EVALUATION DU POTENTIEL FIBREUX ET TEXTILE DE LA CANNE A SUCRE (Saccharum officinarum L.)." Phd thesis, Université de Haute Alsace - Mulhouse, 2013. http://tel.archives-ouvertes.fr/tel-01009321.

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Ce travail de thèse porte sur l'extraction et la caractérisation mécanique des fibres de canne à sucre. A partir de la bagasse de canne à sucre, résidu fibreux de l'industrie sucrière, des techniques d'extractions sont mises en place afin d'extraire des fibres techniques, dont l'analyse des propriétés chimiques et physico-mécaniques définira par la suite, les domaines d'application textile possibles. Les fibres de canne obtenues ont d'abord été étudiées d'un point de vue physique et morphologique, à partir de mesures et d'observations de leurs sections et de leurs profils. Ainsi, l'analyse de la distribution en diamètre et en longueur des fibres ont été étudiés avec l'établissement de paramètres de centrage barbe et hauteur (longueur pondérée à la masse), ont permis de déterminer leurs tailles moyennes, leurs finesses et leurs dispersions tout en vérifiant l'effet des conditions de traitement. Ont ainsi été obtenus différents types de fibres, présentant des propriétés mécaniques (en flexion et en traction) variées en relation avec les changements de structure dus à l'extraction. Les performances mécaniques de ces fibres restent comparables aux autres fibres naturelles, confirmant ainsi leur potentiel textile. Une première piste de valorisation de ces fibres a été envisagée lors de la fabrication d'un fil de canne à sucre. Des essais de filature ont ainsi été menés sur micro-filature, en 100% fibres de canne mais aussi en mélange 30-70% coton/bagasse. Enfin, une introduction à l'approche environnementale basée sur l'analyse de cycle de vie, a été succinctement abordée, ouvrant le champ à d'autres études. Les résultats montrent que le potentiel textile de la canne à sucre est quantifiable, et que ses fibres extractibles, sont comparables à d'autres fibres naturelles non conventionnelles utilisés dans le domaine textile.
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35

Landa, Matthieu. "Développement d'un traitement textile alternatif à base de composés époxyde : Compréhension des réactions en jeu." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEI052.

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Ce travail de thèse est consacré au développement de formulations aqueuses époxyde pouvant être utilisées comme traitement textile « easy-care » sur substrat cellulosique. Ce traitement consiste en l’amélioration des propriétés défroissables et de la stabilité dimensionnelle. Les propriétés « easy-care » sont apportées par des formulations réactives pouvant réticuler chimiquement les microfibrilles de cellulose (via les fonctions hydroxyle). Les formulations, développées lors de ces travaux de thèse, ont pour objectif de substituer celles utilisées actuellement car elles libèrent du formaldéhyde (produit CMR). Après une étude bibliographique des alternatives aux dérivés formaldéhyde, l’utilisation de dérivés époxyde en présence d’un catalyseur acide (acide de Lewis : le tétrafluoroborate de zinc) a été sélectionnée comme stratégie principale. Différentes réactions peuvent subvenir lors du traitement d’un substrat cellulosique par ce type de formulation : -La réticulation des chaînes de cellulose par éthérification (souhaitée pour notre application),-L’hydrolyse acide des fonctions époxyde, -L’oligomérisation cationique des dérivés époxyde. Les deux dernières réactions ont un impact néfaste sur la réactivité de la formulation. Tout d’abord, nous avons souhaité contribuer à une meilleure compréhension du milieu réactionnel « époxyde + alcool + eau + catalyseur », peu étudié dans la littérature, à travers différentes réactions modèles. L’éthérification d’alcool par des dérivés époxyde a notamment été vérifiée. Des formulations, se différenciant par la quantité de catalyseur, la quantité de dérivés époxyde et la nature de l’époxyde, ont été appliquées à l’échelle laboratoire sur un substrat textile modèle (100% coton). Le greffage du dérivé époxyde a été mis en évidence par XPS et IRTF-ATR. L’impact du traitement sur les propriétés défroissables et mécaniques a été évaluée. Une formulation époxyde a été sélectionnée, puis appliquée à un substrat industriel à l’échelle pilote afin de comparer les propriétés obtenues à celles d’un tissu référence
The aim of this thesis is the development of epoxide-based aqueous formulation, which can be used as "easy-care" textile treatment."Easy -care" treatment is applicated to improve wrinkle recovery properties and the dimensionnal stability of textile (cellulosic substrates). This treatment is based on the chemical crosslinking of cellulose microfibers by a crosslinking agent. The formulations developed in this thesis have to substitute the one using formaldehyde derivatives. After a bibliographic study, the epoxide derivatives under acid catalyst (Lewis Acid: zinc tetrafluoroborate) have been selected. Different reactions are possible in the course of the treatment of textile by epoxide in acid media: -Crosslinking of cellulose by etherification, -Acid hydrolysis of epoxide functions, -Cationic polymerization of epoxide derivatives. First, the complex reaction media "epoxide + alcohol + water + acid catalyst" have been investigated by different model reaction studies. The etherification of an alcohol by an epoxide in this media have been highlighted. Then, different epooxid-based aqueous formulation have been developed and experimented as textile treatment at laboratory scale. The formulation are distinguished by the type of epoxide, the quantity of epoxide and the quantity of catalyst. The effect of the treatment on the wrinkle recovery and mechanical properties have been investigated
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36

Boulinguiez, Benoit. "Procédé d'adsorption et régénération électrothermique sur textile de carbone activé - Une solution pour la problématique des COV dans des gaz à fort potentiel énergétique." Phd thesis, Université Rennes 1, 2010. http://tel.archives-ouvertes.fr/tel-00540206.

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Un procédé d'adsorption--électrodésorption sur textile de carbone activé est proposé afin de répondre à la problématique des composés organiques volatils à l'état de traces dans les gaz à fort potentiel énergétique: \emph{biogaz} et \emph{gaz de ville}. Une approche expérimentale en deux parties a été conduite afin de premièrement, sélectionner le matériau adéquat dans les conditions opératoires considérées et modéliser les phénomènes \emph{physico-chimiques} relatifs à l'adsorption et la désorption thermique; deuxièmement, mettre en \oe{}uvre ce matériau dans une unité pilote de purification en continu, à l'échelle du laboratoire. Un échantillon représentatif de COV est retenu: toluène, isopropanol, dichlorométhane, éthanethiol, octaméthylecyclotétrasiloxane et tétrahydrothiophène. L'adsorption et la désorption de ces composés sur différents textiles de carbone activé sont caractérisées, modélisées et quantifiées afin de pouvoir dimensionner l'unité pilote de traitement en continu. L'utilisation d'outils de simulation numérique des écoulements et de l'adsorption en continu amènent une réflexion globale sur les limites liées à la définition et à l'approche habituelle des modèles physiques dans ce type de procédé. Les résultats expérimentaux obtenus avec l'unité pilote de purification en continu offrent un premier jeu de données pour appréhender la faisabilité de ce procédé et dresser la liste des obstacles à surmonter avant tout industrialisation.
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37

Wilson, Virginia H. "The chemistry of phenolic yellowing of textiles." Thesis, University of Salford, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.258352.

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38

Russo, Rachel. "Hanging by a Thread: Enhancing the Forensic Value of Dyed Cotton Trace Evidence through the Application of Novel Techniques in Fiber Discrimination." Honors in the Major Thesis, University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/801.

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This item is only available in print in the UCF Libraries. If this is your Honors Thesis, you can help us make it available online for use by researchers around the world by following the instructions on the distribution consent form at http://library.ucf
Bachelors
Arts and Sciences
Forensic Science
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39

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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40

Olszewski, Amy L. "Synthesis, Biological Functionalization, and Integration ofCarbon Nanotubes for Bio-Sensing Textiles." Youngstown State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1369854838.

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Dominguez, Kimberly. "Leaching of Silver Nanoparticles from Textiles." Ohio University Art and Sciences Honors Theses / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ouashonors155690445799457.

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42

Vieira, Valesca Vargas. "Tecidos têxteis: uma temática para o ensino e aprendizagem de Química." Universidade Federal de Santa Maria, 2017. http://repositorio.ufsm.br/handle/1/12735.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
In this study, we used the theme "Textile Fabrics" to contextualize chemical contents, in order to favor the teaching and learning process of Organic Chemistry contents for students of last year of a public school in the city of Santa Maria, RS. In this sense, we seek theoretical references of the theme "Textile Fabrics" to establish the relations with the corresponding chemical contents of the target-public. From this, we developed a proposal to approach these contents in the classroom, which was evaluated through interventions, applied in five stages. The methodology of the Three Pedagogical Moments associated to different teaching strategies such as experimental activities and case studies was used to establish the relationships between the contents of chemistry and the students' daily life from the perspective of the theme. The results of this research were obtained through different data collection instruments such as questionnaires, textual productions, research and presentation of papers, reports, observations and notes made by the researcher during the interventions, which were analyzed according to the Textual Discursive Analysis. Regarding the results, we observe an evolution in the construction of the knowledge and several abilities of high school students, which were verified through Analytical tools. Hence, it can be concluded that the theme "Textile Fabrics", associated to the use of different teaching methodologies, approximated Chemistry to student’ reality favoring the teaching and learning process of Organic Chemistry contents.
Nesta pesquisa, utilizamos a temática “Tecidos Têxteis” para a contextualização de conteúdos químicos, a fim de favorecer o processo de ensino e aprendizagem de conteúdos de Química Orgânica para estudantes da 3ª série do Ensino Médio de um colégio público da cidade de Santa Maria, RS. Para tanto, buscamos referenciais teóricos da temática escolhida “Tecidos Têxteis” para estabelecermos as relações com os conteúdos de química correspondentes da série escolhida. A partir disso, desenvolvemos uma proposta para abordar estes conteúdos em sala de aula, que foi avaliada através de intervenções, as quais foram aplicadas em cinco etapas. Utilizou-se a metodologia dos Três Momentos Pedagógicos aliadas a diferentes estratégias de ensino como as atividades experimentais e estudo de casos, para estabelecer as relações entre os conteúdos de química com o dia a dia dos estudantes sob a perspectiva da temática. Os resultados desta pesquisa foram obtidos por meio de diferentes instrumentos de coleta de dados como: questionários, produções textuais, pesquisa e apresentação de trabalhos, elaboração de relatórios, observações e anotações realizadas pela pesquisadora durante as intervenções, os quais foram analisados segundo a Análise Textual Discursiva. Com relação aos resultados obtidos, observou-se uma evolução na construção do conhecimento e de diversas habilidades dos estudantes do ensino médio, que foi constatada por meio dos instrumentos de análise utilizados. Portanto, pode-se concluir que a temática “Tecidos Têxteis”, associada ao uso de diferentes metodologias de ensino proporcionou uma aproximação da Química com realidade do estudante favorecendo o processo de ensino e aprendizagem de conteúdos de Química Orgânica.
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43

Volkov, Anton. "Ionic and electronic transport in electrochemical and polymer based systems." Doctoral thesis, Linköpings universitet, Fysik och elektroteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-135429.

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Electrochemical systems, which rely on coupled phenomena of the chemical change and electricity, have been utilized for development an interface between biological systems and conventional electronics.  The development and detailed understanding of the operation mechanism of such interfaces have a great importance to many fields within life science and conventional electronics. Conducting polymer materials are extensively used as a building block in various applications due to their ability to transduce chemical signal to electrical one and vice versa. The mechanism of the coupling between the mass and charge transfer in electrochemical systems, and particularly in conductive polymer based system, is highly complex and depends on various physical and chemical properties of the materials composing the system of interest. The aims of this thesis have been to study electrochemical systems including conductive polymer based systems and provide knowledge for future development of the devices, which can operate with both chemical and electrical signals. Within the thesis, we studied the operation mechanism of ion bipolar junction transistor (IBJT), which have been previously utilized to modulate delivery of charged molecules. We analysed the different operation modes of IBJT and transition between them on the basis of detailed concentration and potential profiles provided by the model. We also performed investigation of capacitive charging in conductive PEDOT:PSS polymer electrode. We demonstrated that capacitive charging of PEDOT:PSS electrode at the cyclic voltammetry, can be understood within a modified Nernst-Planck-Poisson formalism for two phase system in terms of the coupled ion-electron diffusion and migration without invoking the assumption of any redox reactions. Further, we studied electronic structure and optical properties of a self-doped p-type conducting polymer, which can polymerize itself along the stem of the plants. We performed ab initio calculations for this system in undoped, polaron and bipolaron electronic states. Comparison with experimental data confirmed the formation of undoped or bipolaron states in polymer film depending on applied biases. Finally, we performed simulation of the reduction-oxidation reaction at microband array electrodes. We showed that faradaic current density at microband array electrodes increases due to non-linear mass transport on the microscale compared to the corresponding macroscale systems.  The studied microband array electrode was used for developing a laccase-based microband biosensor. The biosensor revealed improved analytical performance, and was utilized for in situ phenol detection.
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44

Carswell, Stewart. "Microanalysis of dyes from textiles." Thesis, Queensland University of Technology, 1991. https://eprints.qut.edu.au/35972/1/35972_Carswell_1991.pdf.

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The discrimination and/or matching of dye extracts is an important aspect of forensic investigations involving textile samples. The aim of this work was to study the use of Fourier transform infrared spectrometry and diffuse reflectance to obtain IR spectra of dye samples, and the subsequent analysis of these spectra using library searching and principle component analysis. The work in this thesis has demonstrated the development of a simple method for obtaining DRIFT spectra of dye samples. Library searching and principle component analysis were used to distinguish between many types of dye samples, including extracts that were not distinguished using TLC.
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45

Parker, Charlotte Clair. "The (bio)chemistry of cell adhesion in edible plant tissues : its role in texture." Thesis, University of East Anglia, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327534.

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46

Rabe, Richard L. "Corona discharge effects on the interfacial adhesion in a sheath-core type composite fiber." Ohio : Ohio University, 1989. http://www.ohiolink.edu/etd/view.cgi?ohiou1172603429.

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47

Karaszi, Zoltan. "Advanced neural network clustering techniques for liquid crystal texture classification." Thesis, Kent State University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1555292.

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This Master Thesis presents a new method of analyzing and classifying liquid crystal textures, using feed-forward neural networks and different clustering techniques. Liquid crystal phases are generally identified by human experts by polarizing optical microscopy observations of textures, based on typical defects, the smoothness or sharpness of domains and the birefringence colors of the films. The thesis aims to establish a novel algorithmic technique for liquid crystal texture analysis and classification. Using image analyzing software, a characterization vector with 22 parameters is extracted for each texture. Advanced clustering algorithms are used to classify textures based on those characteristic parameters. Furthermore, a ranking of the measurements is proposed to refine the accuracy of classification. The proposed methodology will lead to a reliable and simple technique for the physical investigation of liquid crystal materials.

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48

Hedman, Björn. "Dioxin emissions from small-scale combustion of bio-fuel and household waste." Doctoral thesis, Umeå University, Chemistry, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-593.

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Denna avhandling behandlar rökgasutsläpp av persistenta organiska föroreningar, framförallt dioxiner, vid förbränning av fasta biobränslen och torrt hushållsavfall i relativt små anläggningar (5-600 kW) utan avancerad rökgasreningsteknik.

Samförbränning av avfall och biobränsle i effektiva mindre biobränslepannor testades som en alternativ strategi till den vanligen förekommande storskaliga hanteringen och förbränningen fast hushållsavfall. Medan storskalig förbränning av avfall ger investeringsmässiga fördelar med rökgasreningsteknik etc. kan små lokala anläggningar ha transportmässiga fördelar och möjligheter till utnyttjande av lokala biobränsletillgångar. Källsorterat, torrt, brännbart hushållsavfall insamlades från hushåll i glesbygd och samförbrändes i brikettform med energigräset rörflen i 150-600 kW biobränslepannor. Endast undantagsvis understeg dioxinemissionerna gällande gränsvärden för avfallsförbränning och nivåerna av väteklorid i rökgas översteg gränsvärdena flerfaldigt. Det bedömdes att någon form av extra rökgasrening är nödvändig för att säkerställa nivågränserna. Dioxiner hittades också i det eldade avfallet, framförallt i textilfraktionen. Dioxinmängderna i rökgaserna var oftast lägre än i det ingående bränslet.

Intermittent pelletseldning gav oväntat höga utsläpp av dioxiner med en emissionsfaktor på 28 ng(WHO-TEQ)/kg. Vedeldning i en modern miljömärkt villapanna gav betydligt lägre utsläpp av dioxiner än eldning i en gammal kombipanna och eldning med full lufttillförsel, som kan jämföras med användning av ackumulatortank, resulterade i upp till 90% minskning av utsläpp av dioxiner jämfört med eldning med reducerat lufttillskott (’pyreldning’). Eldning av plastavfall i en vedpanna gav höga utsläpp av dioxiner.

Okontrollerad förbränning av trädgårdsavfall och hushålls avfall i tunna eller som öppen eld ’bakgårdsbränning’, gav stora variationer i utsläppsnivåer som bara delvis kunde kopplas till avfallsinnehåll. Resultaten visar att denna typ av förbränning kan vara en betydande källa till dioxiner i miljön, och ett emissionsfaktorintervall på 4-72 ng (WHO-TEQ)/kg föreslås för bedömningar av utsläpp från backgårdsbränning av avfall med låga eller måttliga klorhalter.

En sammanfattande slutsats av alla försök är att dioxin utsläpp beror på komplicerade samband mellan bränsleinnehåll och förbränningsbetingelser. Bränslen med mycket höga klorhalter av ger oftast högre utsläpp av dioxiner än bränslen med låga klorhalter medan små skillnader döljs av variationer i förbränningsbetingelser.


This thesis deals with emissions of persistent organic pollutants, primarily dioxins, from the combustion of solid biofuels and dry combustible household waste in relatively small facilities, 5-600 kW, without advanced air pollution controls.

Co-combustion of waste and biofuel in effective small boilers was tested as an alternative to prevailing large-scale management and combustion strategies for handling municipal solid waste. This approach includes no advanced air pollution control systems, but offers two advantages: limiting transport and providing scope to use local biofuel resources. Source-sorted, dry, combustible household waste was collected from households in a sparsely populated area and co-combusted as briquettes together with reed canary-grass in 150-600 kW biofuel boilers. Most trials showed difficulties to meet regulative limits for the emissions of dioxins valid for incineration of MSW and the regulated limits for emissions of hydrochloric acid were exceeded manifold. It was concluded that additional flue-gas cleaning will be needed to ensure that emissions are sufficiently low. Dioxins were also found in the waste, especially in the textile fraction. The mass of dioxins in the flue-gas emissions was generally lower than the mass in the fuel input.

Intermittent combustion of wood pellets in a residential boiler resulted in an unexpectedly high dioxin emissions factor of 28 ng (WHO-TEQ)/kg fuel. Combustion of wood in a modern environmentally certified boiler yielded considerably lower dioxin emissions than combustion in an old boiler, and combustion with a full air supply, i.e. with use of heat storage tank, resulted in up to 90% reductions in dioxin emission factors compared to combustion with reduced air supply. Combustion of plastic waste in a residential wood boiler resulted in high emissions of dioxins.

Tests of uncontrolled combustion of garden and household waste in barrels or open fires, ‘backyard burnings’, resulted in emissions with large variations that could only be partly correlated to the waste constituents. The results imply that this may be an important source of dioxins in the environment and an emission factor range of 4-72 ng (WHO-TEQ)/kg is suggested for estimating emissions from backyard burnings of lightly and moderately chlorine-contaminated waste.

A summarized conclusion from all of the experiments is that predicting emission levels from waste contents is not straightforward (except that fuels with very high chlorine levels will usually result in high levels of dioxins in flue-gas emissions). Moderate differences in chlorine levels will usually be masked by the effect of variations in combustion conditions.

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49

King, Tracy-Anne. "Calcium carbonate crystallisation : the effect of synthetic peptides on crystal growth, morphology and texture." Thesis, University of Salford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244845.

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50

Li, Hualong 1967. "Computer simulation of oxide texture and microstructure formation and their effects on oxidation kinetics." Thesis, McGill University, 1998. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=35467.

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Abstract:
Computer models of oxide texture and microstructure development and oxidation kinetics have been developed. The first computer model enables the evaluation of the effects of various factors on oxide texture and microstructure development. The second computer model enables the evaluation of the effects of oxide texture and microstructure on oxidation kinetics.
Two examples of Ni single crystal and polycrystalline, Zr-2.5%Nb are used to illustrate the proposed computer models. Simplified oxidation mechanisms on Ni and Zr have been proposed.
In the first system, the simulation of oxide texture and oxidation kinetics on the {100} and {111} oriented single crystal Nickel substrate is analyzed. At the nucleation stage the oxide grain orientation is determined by lattice matching between the oxide and the metal substrate. At the stage of oxide grain growth, oxide surface free energy plays an important role. The simulated oxide textures are in good agreement with experimental results. The observed difference in the oxidation kinetics of the two samples is explained by difference in oxide textures formed on the two single crystal substrates. The high percentage of Sigma3 twin boundaries found in the oxide formed on the {111} substrate indicates that the presence of these boundaries significantly improves oxidation resistance.
In the second system where oxidation on Zr-2.5%Nb is simulated and analyzed, lattice matching between the oxide and the metal substrate is used to determine the oxide orientation at the nucleation stage. At the stage of oxide grain growth, oxide orientation is determined by minimizing the compressive stress that is parallel to the metal/oxide interface. Four samples with different substrate orientations have been used in study. The simulated oxide textures and microstructures are in good agreement with experimental results. During the simulation of oxidation kinetics, it is found that oxygen transport through Zr oxide film takes place mainly through two diffusion paths. The first diffusion path is through oxide grain boundaries formed in the bulk alpha-Zr grain region and the second one is through oxide grain boundaries formed at the alpha-Zr grain boundaries and beta-Zr grain region.
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