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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

THE EVALUATION OF ELECTRO-CHEMICALLY ACTIVATED WATER AS AN ALTERNATIVE DETERGENT FOR POLYAMIDE AND MACHINE WASHABLE WOOL

van Heerden, Natasha 17 October 2011 (has links)
The electro-chemical activation of aqueous media is relatively new technology. The alkaline part of the activated media (catholyte) is used in a wide variety of applications due to outstanding detergency properties. The standard phosphate based detergents currently used by consumers cause a negative impact on the environment. Catholyte provides an environmental friendlier alternative as it returns to be neutral water within 48 hours after activation. Although catholyte may be an environmentally friendly medium for washing, the influence that it has on the properties of textile materials, for example wool and polyamide is still only based upon speculation. Little is also known about the soil removal efficiency of this medium on wool and polyamide. The aim of this study was to evaluate electro-chemically activated water (catholyte) as an alternative detergent for machine washable wool and polyamide 6,6. This was done by determining the influence of catholyte on certain important properties of these textile fabrics as well as the soil removal efficiency. The machine washable wool and polyamide 6,6 textile fabrics were laundered at 30°C and 40°C with catholyte, phosphate detergent or distilled water for five, ten, twenty or fifty laundering cycles respectively. The standard test methods for laundering (AATCC 61) and measuring the tearing strength (ASTM D1424), tensile strength (ISO/SANS 13934-1), wrinkle recovery (AATCC 66), bending length (BS 3356), soil removal (AATCC 135) and dimensional change were used. Analysis of variance (ANOVA) was used for the statistical interpretation of the results obtained. Catholyte, detergent and distilled water caused a significant decrease in the tearing strength of both the polyamide 6,6 and wool fabrics. The temperature had no significant influence on the tearing strength of polyamide 6,6 fabric although it caused a significant decrease in the tearing strength of wool. The number of laundering cycles caused a significant decrease in the tearing strength of the warp yarns of polyamide 6,6 as well as the weft and warp yarns of wool, however it did not have a significant influence on the weft yarns of polyamide 6,6. Catholyte, detergent and distilled water as well as the temperature and number of laundering cycles did not have a significant influence on the tensile strength on the weft yarns of the polyamide 6,6. It did however cause a significant decrease in tensile strength of the warp yarns of polyamide 6,6 and the weft and warp yarns of wool. Catholyte, detergent and distilled water as well as the temperature and number of laundering cycles had a significant influence on the bending length (stiffness) of polyamide 6,6 and wool, causing the fabric to become stiffer. Catholyte, detergent and distilled water caused a significant increase in the wrinkle recovery in the weft of polyamide 6,6 and decrease in wrinkle recovery in the weft of wool. It did not have a significant influence in the warp of wool and polyamide 6,6. The temperature had no significant influence on the wrinkle recovery of the wool and weft of polyamide, although it caused a significant fluctuation in the warp of polyamide 6,6. The number of laundering cycles caused a significant fluctuation in the wrinkle recovery of the polyamide 6,6 and wool fabrics. Catholyte, detergent and distilled water, as well as the temperature and number of laundering cycles did not have a significant influence on the dimensional stability of polyamide 6,6. It did however cause the wool fabric to shrink significantly. Catholyte and detergent proved to be significantly effective in removing soil from polyamide 6,6 and wool. The temperature only had a significant influence on soil removal from the wool.
22

THE WATER, ENERGY AND SOIL REMOVAL EFFICIENCY OF A TOP AND A FRONT LOADER WASHING MACHINE

Seiphetlheng, Kgalalelo 16 August 2012 (has links)
Water and energy are used in the domestic laundering processes for optimum soil and stain removal. Water and energy conservation are important issues in the quest for more environment friendly household practices. Washing machines have been invented as household gadgets making laundry easier and faster. Common types of washing machine include top loaders, front loaders and twin tubs. Literature indicate that top loaders use less electricity but more water and front loaders use less water but more electricity. However efficient soil removal is the main concern of the consumer. The purpose of the study was to determine water, energy and soil removal efficiency of a top loader and a front loader washing machine. A quantitative research strategy was used and controlled experiments were conducted in order to attain accurate data. An 8.0 kg capacity top loader and an 8.5 kg capacity front loader of the same manufacturer were purchased. The âdaily wash programâ and the âquick wash programâ of both machines were selected as wash programs for the project. Cold wash (water at room temperature) was used for the top loader and cold wash, 30 °C, 40 °C and 60 °C for the front loader. A 5kg load of 3 samples of C-09 cotton (soiled with pigment oil, purchased from CFT) and cotton filler cloths were used for each wash cycle and each cycle repeated three times. The efficiency of the machines and programs to remove stains were tested on the following stains: CS-103 red wine, CS-12 blackcurrant, CS-BC-03 tea, C-BC-02 coffee, CS-28 rice starch, CS-26 corn starch, CS-6 dressing, CS-73 locust bean gum, CS-54 oatmeal/chocolate, CS-38 egg yolk/pigment, CS-01 blood, C-05 blood/milk/ink, CS-08 grass, CS-02 cocoa, C-10 pigment/oil/milk, C-02 olive oil/soot, CS-32 sebum bey, CS-17 make-up and CS-216 lipstick. 60g Non phosphate ECE reference detergent without optical brightener was used. Redeposition of soil was determined on CN-11 white cotton. The drained water was collected and measured in litres. The energy consumption was measured in watt-hour in every program. Soil removal was measured with a colorimeter in CIE L*a*b* colour scale (AATCC test method 61-2010) and an analysis of variance was used to aid in the interpretation of the data. The results of the study indicate that, the top loader used more water than the front loader. The daily wash used more water than the quick wash in both the top loader and front loader. The front loader used more energy than the top loader at cold wash. More energy was used in the daily wash than quick wash of the front loader. It was also evident that the daily wash program in both machines was more efficient in soil and stain removal than the quick wash. At cold wash the daily wash was more efficient in soil and stain removal than the quick wash program but at 60 °C there was no difference in the rate of stain removal in both the quick and daily wash programs. The best soil and stain removal was observed at 60 °C in both the quick and daily programs. The top loader machine used more water, less energy and removed less soil and stain. It was also evident that, the front loader washing machine is more efficient in soil and stain removal and it uses less water but it uses more energy than the top loader machine.
23

EVALUATION OF THE ANTIMICROBIAL EFFECT AND STRENGTH PROPERTIES OF POLYESTER, POLYESTER/COTTON AND COTTON TREATED WITH ANOLYTE

Vermaas, Jana F 16 August 2012 (has links)
Textile materials are usually treated with chemicals like sodium hypochlorite and high temperatures to ensure sterility. This poses two potential problems: (1) it has a negative effect on strength properties of the textile fabric; (2) the harmful chemicals are discarded into the environment. Therefore, better and safer methods need to be investigated. A process has been developed where electro-chemically activated water (Anolyte) is produced by an anode-cathode system and the process is described as a change of the molecular state of the water. After production, the Anolyte exists in a metastable state while containing many free radicals and a variety of molecules and a very high oxidation-reduction potential. It returns to a stable state after 48 hours and become inactive again and, therefore, it is not a threat to the environment when discarded after use. Anolyte has been shown to be an effective disinfection agent in other areas such as the food industry. The aim of this study was to determine if Anolyte could reduce E. coli and Staph. aureus on textiles to the same extent as sodium hypochlorite and be effective without implementing such high temperatures. The influence of the Anolyte on textile material should also be evaluated to ensure that it could be used without damaging textile materials more than the currently used disinfection agents. The antimicrobial effect of the Anolyte was determined by contaminating cotton, polyester and polyester/cotton fabric swatches with E. coli and Staph. aureus, respectively. Survival was determined after laundering with the respective wash liquors. AATCC Test Method 61- 2009 was used with the LaunderOmeter. Wash liquors included filtered water, phosphate reference detergent B, sodium hypochlorite and Anolyte. Temperatures were maintained at 24, 30 or 60°C. The cotton, polyester/cotton and polyester were laundered for 5, 10 or 20 cycles respectively for the evaluation of the influence on tensile strength and tearing strength. The tensile strength tests were conducted with the Instron Tensile Tester and ISO/SANS 13934-1:1999 test method. The tearing strength tests were conducted with the Elmendorf Tearing Strength tester as per ASTM Test Method D 1424 - 63. The results indicated that Anolyte destroyed all E. coli and Staph. aureus on all the fabrics regardless of the temperature. The effect of the other agents were enhanced by the increasing temperature, but after laundering at 60°C no survival was found as a result of the high temperature. The Anolyte did not influence the strength properties of the cotton, polyester and polyester/cotton fabrics to a larger extent than the detergent or sodium hypochlorite solution. An increase in maximum load required to break the fabric and displacement at maximum load was found for the cotton and polyester/cotton fabrics after laundering treatments, while a decrease was caused after laundering of the polyester fabric. A decrease in tearing strength of all the fabrics was found after laundering with the treatments. The Anolyte also did not affect the dimensional stability of the fabrics. It could be concluded that the Anolyte is a viable alternative to currently used sodium hypochlorite, while it is effective at low temperatures. The Anolyte do not affect the textile fabrics more negatively than the detergent and sodium hypochlorite combination, and could, therefore, be a successful alternative.
24

A systematic analysis of consumer buyer behaviour in urban China

Kwok, Simon, Marketing, Australian School of Business, UNSW January 2006 (has links)
Since economic reforms began in 1978, China has experienced rapid economic growth and is now arguably the world???s largest consumer market. However, despite the size and potential of the Chinese market, there is a serious lack of formal understanding of Chinese buyer behaviour. The broad aim of this research is to understand patterns of buyer behaviour through a systematic analysis of the purchasing of fast-moving consumer goods (FMCGs) by urban Chinese consumers. Several specific research questions are addressed: ??? What patterns of brand purchasing and brand loyalty do urban Chinese consumers exhibit? ??? Do these patterns generalise across content, spatial and temporal dimensions? ??? Are there any systematic significant bases of segmentation within the FMCG markets that are studied? ??? What key implications are to be drawn by academics and practitioners? ??? More generally, what is the value of adopting a systematic approach to research in this area of enquiry? ??? Also, what is the value of applying and extending models developed in the West to the Chinese consumer context? The research is divided into two main studies. The first involves secondary consumer panel data and focuses on brand purchasing and loyalty behaviour. Analysis is conducted using the Dirichlet model, which provides theoretical predictions for a range of brand performance measures. The second study involves primary consumer panel data and examines potential bases of segmentation. Analysis is based on the Generalised Dirichlet Model, which enables the impact of covariates on buyer behaviour to be assessed. It is found that the patterns of Chinese buyer behaviour for FMCGs are generally similar to those in the West. Results unique to the Chinese market are also identified. Importantly, the results and patterns generalise across all dimensions of analysis (that is, for brands within product categories, store types and store chains, and in different regions and cities, and in different time periods). Also, there is a lack of consumer segmentation among directly competing brands within the product categories that are studied. The findings not only make a strong empirical contribution but also have important academic and managerial implications.
25

Consumerism in the 1960's; a study of the development of, underlying reasons for, and business reaction to today's consumer protection movement.

Gaedeke, Ralph M. January 1900 (has links)
Thesis (D.B.A.)--University of Washington. / Bibliography: l. [237]-247.
26

Der finanzierte Verbrauchsgüterkauf im deutschen und französischen Recht : rechtsvergleichende Untersuchung zum Verbraucherschutzrecht bei finanzierten Verträgen /

Teufel, Anne Julia. January 2007 (has links)
Zugl.: Saarbrücken, Univ., Diss., 2007 / Includes bibliographical references (p. 257-272) and index.
27

A model statute to regulate unfair advertising and sales practices in Alabama

Harris, James Robert, January 1973 (has links)
Thesis--University of Florida. / Description based on print version record. Typescript. Vita. Bibliography: leaves 266-279.
28

Household debt service burden outlook an exploration on the effect of credit constraints /

Zhao, Jing, January 2003 (has links)
Thesis (Ph. D.)--Ohio State University, 2003. / Title from first page of PDF file. Document formatted into pages; contains xii, 210 p.; also includes graphics (some col.) Includes bibliographical references (p. 203-210). Available online via OhioLINK's ETD Center
29

Characteristics of concerned consumers with implications for consumer education programs

Doll-Yogerst, Donna C. January 1985 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1985. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 94-97).
30

A cross-sectional analysis of consumer learning among younger vs. older adolescents

Moore, Roy Leamon, January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1974. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

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