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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.
651

Development and Evaluation of an Aquifer Capability Screening Tool Pilot Study: Clarence-Rockland, Ontario

Morton, Samuel R. January 2015 (has links)
Increased development pressure led the United Counties of Prescott and Russell to seek development of a GIS-based Aquifer Capability Screening Tool (ACST). A Pilot ACST, developed by a project partner within this study, was made for the City of Clarence-Rockland, Ontario, and consists of several maps showing delineated areas where there may be groundwater limitations in terms of quality or quantity. This study gathered the chemistry data needed for the Pilot ACST from 127 domestic dug and drilled wells. The results showed exceedances of provincial health and aesthetic standards, which were then used to delineate maps for the Pilot ACST. An evaluation of the necessary data source and sampling scale for ACST development revealed that data gathered from existing reports was inadequate for various reasons and sampling scale should be on a grid 2x2 km2 or smaller. Further recommendations were provided for future ACST development studies.
652

En mittpunkt för aktivitet : En studie om utformningen av ett multifunktionellt förskolerum

Hägglund, Anna-Sara January 2017 (has links)
This thesis is a study on how to design a multipurpose preschool room, where the  organization and structure of the room communicates its functions and purpose. The purpose with the study is to design a room that can be a tool for the preschool teachers and that helps children develop their curiosity and learning skills. The specific case takes place at Krongatan preschool in Eskilstuna. The study evolves around theories about form, colour, light and how it can be used in the design of a multipurpose preschool environment. The study also includes theories about affordance, design principals, spatial elements and organization of preschool environments. Empirical data has been collected through interviews, spatial analysis and observations. The theories together with the collected empiric data have resulted in a design proposal. The proposed design consists of spatial elements to make the environment legible and create an environment that invites to different activities. / Det här examensarbetet undersöker hur ett multifunktionellt förskolerum kan utformas för att kommunicera och stödja olika aktiviteter. Förskolerummet används till både aktiva och lugna aktiviteter och ska vara ett hjälpmedel för att stödja barns lärande och utveckling. Genom att rummet kan kommunicera sina funktioner ger det möjlighet för barnen att förstå och använda rummet. På så sätt kan pedagogerna använda rummet som ett redskap. Studien har genomförts i samarbete med Krongatans förskola i Eskilstuna. Den undersöker hur de rumsliga elementen färg, ljus och form kan användas i utformningen för att skapa ett multifunktionellt rum. Studien tar även upp teorier om affordance, designprinciper, rumsliga element och utformning av förskolemiljöer. Empiriska data har samlats in genom intervju, rumsanalys och observation. Teorierna tillsammans med den insamlade empirin har resulterat i ett gestaltningsförslag. Gestaltningsförslaget består av rumsliga element som tydliggör rummets olika delar och bjuder in till olika aktiviteter.
653

Využití metody barvově slovních asociací v marketingu / Using of colour-word association method in marketing

Popelka, Milan January 2011 (has links)
Diploma thesis aims to show the possibilities of using the method of colour-word associations in marketing. For this purpose, the first chapter deals with the psychology of consumer. The second chapter is following by an overview of marketing tools. The third chapter focuses on standard methods of marketing research, supplemented by field of neuromarketing. The colour-word association method is characterized in detail in the forth chapter, where the general directions of its possible using are defined. Examples of using the method of colour-word associations in marketing research are presented in the fifth chapter. The practically usable outputs for the needs of marketers are introduced by some real researches undertaken by Zamestnanci.com Ltd.
654

Motivace a spokojenost zaměstnanců ve vybrané organizaci / Motivation and satisfaction of employees in a selected company

Bošková, Markéta January 2012 (has links)
The aim of the diploma thesis is to evaluate the motivation and satisfaction of employees in a selected company. The thesis is divided into two parts -- theoretical and practical. First, the thesis defines the theoretical concept of motivation and satisfaction and defines a projective method called Colour Association Technique (CAT) from the concept of Balance Management. The practical part of the thesis presents the company where the research was done. Further methodology of research is presented in this part. In the methodology of research a questionnaire survey was chosen. A questionnaire survey focused on 7 areas of motivation and satisfaction covering 25 study-factors. Further, individual interviews were held with a selected sample of employees, and the projective method mentioned was used. The main body of the practical part consists of an evaluation of the results using all research methods. Individual results are compared and in conclusion recommendations for improving the current situation in the company are suggested. These final recommendations may become a basis for the future development of an optimal motivation program, which the company has not yet implemented.
655

Analýza schopnosti jasového analyzátoru LDA - LumiDISP měřit náhradní teplotu chromatičnosti / Analysis of luminance analyser LDA - LumiDISP application for correlated color temperature measurement

Vlček, Pavel January 2021 (has links)
This master's thesis deals with the search of commercially available luminance analysers and cameras that use the measurement of correlated colour temperature. It also deals with calculations of correlated colour temperature according to various available methods. The luminance analyser LDA-LumiDISP is based on a DSLR camera. The principle of its operation and possible errors in capturing pictures are discussed here. The work deals with extensive testing of the LDA-LumiDISP luminance analyser, which is primarily intended for measuring luminance in the set scene, but can also be used to measure the correlated colour temperature. The device is being tested in terms of measuring the correlated colour temperature in laboratory and field conditions. The result of the master's thesis is the calculation of measurements uncertainty for certain light sources and the optimization of the measuring algorithm to reduce them.
656

Sledování změn hodnot vybraných ukazatelů jakosti pitné vody během její dopravy a skladování / Monitoring of changes of drinking water quality during accumulation and distribution

Vaňková, Jitka January 2008 (has links)
Theoretical part of the diploma thesis purveys information on drinking water and quality requirements, changes of drinking water quality during distribution and accumulation caused by disinfection, chemical processes, corrosion of constructional materials, incrusting solids, biofilms, nitrification of ammonia nitrogen, sediments in pipelines, elution of harmful matter. Attention was given to drinking water quality indicators which are associated with changes in drinking water distribution systems. In experimental part are studied changes of drinking water quality during distribution on the basis of selected drinking water quality indicators. There is specifically chemical oxygen demand, concentration of iron, manganese, ammonia ions, nitrites, nitrates, chloroform and chlorine. For periodical monitoring were selected suitable locality within the framework of Brno distribution system; for illustration were taken water samples from distribution systems of drinking water treatment plants Švařec, Vír, Štítary and Mostiště. For selected methods of analytical determination of above mentioned drinking water quality indicators are presented their characteristics. Obtained information on drinking water quality is mentioned in tabular and graphical form.
657

Rozpoznávání vzorů / Pattern recognition

Pelc, Matěj January 2008 (has links)
This paper proposes robust algorithm for detection of traffic signs in well light conditional. The algorithm uses colour based segmentation method for finding red traffic signs. Fast radial symmetry method FRS is used for identification of constituent shapes. Traffic signs are divided into four classes on the basis of the method.
658

Studium faktorů ovlivňujících tvorbu těkavých aromaticky aktivních látek v přírodních materiálech / Study of Factors Influencing Creation of Volatile Aroma Active Compounds in Natural Materials

Loupancová, Blanka January 2012 (has links)
The production of high-quality foods requires the precise control of factors influencing their quality. The aim of this doctoral thesis was to monitor the influence of sterilization heating and storage time and temperature on selected parameters of model food matrix using suitable physical, chemical and sensory methods. Sterilized processed cheese was chosen as the model matrix. Processed cheeses are milk protein concentrates, produced by melting of mixture of natural cheeses, emulsifying salts, water and other dairy and/or non dairy ingredients. Desirable transformation of this mixture to homogenous, smooth, shiny mass with desired textural, structural, rheologic and sensory properties is caused by using high temperature (about 80-100 °C) during melting. Sterilized processed cheese is subjected to additional sterilization heating (above 100 °C) after production, significantly elongating its durability. The processed cheeses (dry matter 40 % w/w, fat in dry matter 45 % w/w) were analyzed in this work, the part of them was sterilized (117 °C 20 min). Cheeses were stored at various temperatures (cold 6 ± 2 °C, laboratory 23 ± 2 °C and elevated 40 ± 2 °C), sterilized cheeses for 2 years, non sterilized for 1 year. During storage, the samples for physical (instrumental measuring of colour and texture), chemical (assessment of fatty acids and aroma compounds) and sensory (paired preference test, ranking test and evaluation using scale) analyses were taken at regular intervals. The influence of sterilization heating and for another the influence of storage conditions on mentioned parameters were investigated. Non sterilized processed cheese kept their very good quality during all the declared durability (4 months), however, then the significant worsening of most sensory properties was observed. In consequence of sterilization heating the changes of cheese colour and texture were observed, confirmed by both sensory and instrumental assessment. The impairment of taste and aroma was also found. These changes are obvious immediately after production and differences were observed during all the durability. In the case of sterilized processed cheese, the significant impairment of single sensory properties was determined, the highest in the case of texture, taste and aroma. The results of instrumental techniques confirm conclusions from sensory evaluation. The measurements of colour and texture vindicate the formation of darker colour (increasing total difference of colour delta E*) and higher hardness (increasing Fmax) of sterilized processed cheeses, continuing during storage. The worsening of taste and aroma is in accordance with lower content of aroma active compounds and selected fatty acids.
659

À l’origine des couleurs des images photochromatiques d’Edmond Becquerel : étude par spectroscopies et microscopies électroniques / On the origin of colours of Edmond Becquerel’s photochromatic images : a spectroscopy and electron microscopy study

Seauve, Victor de 21 December 2018 (has links)
Les premières photographies couleurs produites par Edmond Becquerel au Muséum d’Histoire naturelle à Paris en 1848 ont suscité un débat scientifique intense tout au long du XIXème siècle. La question de l’origine des couleurs de ces photographies a vu s’affronter les partisans d’une hypothèse pigmentaire et ceux d’une hypothèse interférentielle. Au cours du XXème siècle, cette question n’a pas été définitivement tranchée. Ce travail doctoral se propose d’appréhender la nature de ces images dites « photochromatiques » par une approche expérimentale. Nous nous sommes dans un premier temps intéressés aux étapes de sensibilisation du plaqué argent et d’exposition de la surface sensible aux rayonnements visibles, dans le but de répliquer le procédé Becquerel et de comprendre la photosensibilité de ces images. Les propriétés optiques des couches sensibles et colorées ont été caractérisées en spectroscopie UV-visible et mises en relation avec leurs compositions chimiques (étudiées en XAS) et leurs morphologies, de l’échelle micro- à nanométrique (étudiées en MEB et TEM). La grande sensibilité des échantillons aux faisceaux photoniques (UV-visible et rayons X) et électroniques a imposé un développement méthodologique afin de comprendre et de limiter les effets de sonde. Les résultats de cette recherche permettent de réfuter l’hypothèse de phénomènes interférentiels comme origine des couleurs des images photochromatiques, hypothèse qui prévaut dans la littérature depuis la fin du XIXème siècle. Les couches sensibles et colorées sont constituées de grains de chlorure d’argent micrométriques décorés de nanoparticules d’argent. Ces nanoparticules d’argent, que nous avons étudiées en EELS low loss, sont responsables de l’absorption dans le visible des couches sensibles et colorées par résonance de plasmons de surface. Ceci nous conduit à proposer une origine plasmonique aux couleurs des images photochromatiques, hypothèse discutée dans cette thèse. / The first colour photographs were produced in 1848 by Edmond Becquerel at the Museum of natural History in Paris. The origin of their colours motivated an intense debate between the scientists during the XIXth century. Two main hypotheses were proposed, namely a pigmentary hypothesis and an interferential hypothesis. Nowadays the question of the colours of those photochromatic images is still not settled and this doctoral research aims at addressing it by an experimental approach. We first studied the sensitizing of the silver plate and the exposure of the sensitive surface to light in order to replicate the Becquerel process and to gain information on the photosensitivity of these images. The optical properties of the sensitized and coloured layers were characterized by UV-visible spectroscopy and related to their chemical composition (studied by XAS) and their morphologies, from the micro to the nanoscale (studied by SEM and TEM). A methodological development was necessary to understand and overcome the sensitivity of the samples to photonic beams (UV-visible and X-rays) and electronic beams. The results allow us to reject the interferential hypothesis, which prevailed since the end of the XIXth century. The sensitized and coloured layers consist in micrometric silver chloride grains decorated by silver nanoparticles. Besides, these nanoparticles, which we investigated by low loss EELS, are responsible for the visible absorption of sensitized and coloured layers through surface plasmon resonance. We suggest that the photochromatic images colours have a plasmonic origin and hereby discuss this hypothesis.
660

Variation B-carotene content and physicochemical properties of orange-fleshed sweet potato (Ipomoea batatas (L.) Lam) cultivars grown in Limpopo Province, South Africa

Silungwe, Henry 18 September 2017 (has links)
PhD (Agric) (Food Science and Technology) / Department Food Science and Technology / In recent years, there has been a lot of interest in orange fleshed sweet potato (OFSP) [Ipomoea batatas (L.) Lam] cultivar, as a cheaper source of vitamin A. In Southern Africa, reports have shown that one in every three children has deficiency in vitamin A. This study investigated the variations in β-carotene (vitamin A precursor) content among selected OFSP cultivars grown in Limpopo Province, South Africa. In addition, the study investigated the effects of location on functional properties, total carotenoids and antioxidant profile of the sweet potato flour as well as their physicochemical, functional and nutritional properties. Four (4) sweet potato cultivars [Dagga, Bophelo, Impilo (orange fleshed) and Mvuvhelo (cream fleshed)] were obtained from two locations, namely, University of Venda (Univen) agricultural experimental farm and Tshiombo irrigation scheme (Tshiombo) and analysed for pasting, functional, physicochemical and nutritional properties. The sweet potato flours from these two locations were also analysed by computed tomographic (CT) scans for flour particle density. Mineral and microstructure of OFSP flours were analysed by scanning electron microscope (SEM). All measurements, except the tristimulus L* a* b* and other colour parameters from five replicates, were performed in triplicate. Statistical analysis was performed using a one-way analysis of variance and means were separated using Duncan’s multiple range test; P < 0.05 was considered to be statistically significant. Pearson’s correlation coefficients were used to determine the correlation among functional, physicochemical, nutritional and pasting properties of sweet potato flour. β-carotene content varied significantly between the two locations from 70.98 ± 0.8 μg/g (Tshiombo) to 86.09 ± 2.0 μg/g (Univen), among cultivars from 1.71 ± 0.0 μg/g (Mvuvhelo) to 201.50 ± 1.0 μg/g (Dagga) and among orange fleshed (Dagga, Bophelo and Impilo) flours from 28.38 ± 0.2 μg/g (Impilo) to 201.50 ± 1.0 μg/g (Dagga). There was a similar trend in the contents of α-carotene to that of β-carotene from the two locations, which ranged from 0.63 ± 0.0 mol/L (Tshiombo) to 1.01 ± 0.0 mol/L (Univen). Mvuvhelo had significantly the lowest α-carotene content (0.50 ± 0.0 mol/L) and Impilo the highest (1.28 ± 0.0 mol/L). The total carotenoids was highest for Impilo (7.56 μg/g) and lowest for Mvuvhelo (1.33 ± 0.1 μg/g) but did not vary significantly (P > 0.05) between ii the locations. The antioxidant activity, based on 2, 2-diphenyl-1picrylhydrazyl (DPPH) free radical scavenging activity, was significantly highest in Bophelo (63.37 ± 0.8 mMAAE ml-1) and lowest in Dagga (26.93 ± 1.4 mMAAE ml-1) flours. The ferric reducing antioxidant power (FRAP) varied significantly across the locations and among the cultivars and ranged from 14.45 ± 0.3 μMTE ml-1 (Tshiombo) to 17.40 ± 1.1 μMTE ml-1 (Univen). FRAP was significantly highest in Impilo (21.12 ± 2.1 μMTE ml-1) and lowest in Mvuvhelo (8.16 ± 2.0 μMTE ml-1). Total carotenoid content positively correlated with DPPH (0.486*), FRAP (0.830**), β-carotene (0.370*), and α-carotene (0.424*). The antioxidant content and the radical scavenging activity were significantly correlated (0.563**). Vitamin A content was significantly lowest (6.88 ± 0.38 μg/g retinol) in Dagga flour and highest (7.97 ± 0.25 μg/g) in Impilo flour. Protein content varied significantly across the two locations and ranged from 4.23% (Tshiombo) to 7.16% (Univen). Dagga had significantly the lowest (3.47%) protein content while Impilo had the highest (7.53%). The fat content of the flours varied significantly between the two locations ranging from 0.63% (Tshiombo) to 1.01% (Univen). The protein content was positively correlated 0.594** and 0.421* to vitamin A and fat contents respectively. The Bophelo colour luminosity was significantly lower (L* 76.2) than the other two OFSP, Dagga (L* 83.51) and Impilo (L* 82.07). Bophelo a* (14.09) also differed significantly across all sweet potato cultivars. All cultivars differed significantly in b* values. Colour intensity (ΔE*) ranged from 15.87 to 38.48 for Mvuvhelo and Bophelo, respectively. Chroma ranged from 87.52 to 84.95 for Dagga and Mvuvhelo respectively. Total starch content was significantly different in all sweet potato cultivars and ranged from 244.07 μg/100 g (Bophelo) to 325.04 mg/g (Dagga). Resistant starch differed significantly in all sweet potato cultivars ranging from 1.21 μg/100 g dwb (Bophelo) to 7.07 μg/100 g dwb (Impilo). Ash content was significantly different in all cultivars and ranged from 3.17% (Dagga) to 3.79% (Bophelo). Water holding capacity (WHC) varied significantly across the two locations and ranged from 1.44 g H2O/g DM (Tshiombo) to 1.72 g H2O/g DM (Univen). Bophelo had significantly the lowest (1.27 g H2O/g DM) WHC and Impilo the highest (1.99 g H2O/g DM). The ash content negatively correlated to total starch (-0.928**) but positively iii correlated to WHC (0.654**). Peak viscosity differed significantly across all cultivars under study and ranged from 126.54 RVU (Bophelo) to 302.36 RVU. (Dagga). There was significant difference in trough viscosity across all cultivars ranging from 55.97 RVU (Impilo) to 280.78 RVU (Dagga). There were significant differences in the final viscosity across all cultivars ranging from 78.99 RVU (Impilo) to 319.26 (Dagga). Peak time viscosity varied significantly across all cultivars ranging from 3.87 min (Impilo) to 8.47 min. (Bophelo). Dagga cultivar had significantly the highest pasting temperature (94.16oC) and Bophelo the lowest (77.75oC). The setback viscosity was significantly highest 51.10 RVU (Mvuvhelo) and lowest 23.01 RVU (Impilo). All cultivars from the two locations consistently showed high potassium content ranging from 0.46% (Impilo) to 1.38% (Dagga) as compared to other minerals such as magnesium, calcium and chlorine which ranged from 0.16% (Impilo) to 0.34%. (Dagga). The CT scans revealed that there was a possibility of evaluating the effect of location on the density of granules of sweet potato flour and also the inherent differences in granular distribution of various sweet potato cultivars. SEM revealed high amounts of potassium, magnesium and chlorine. A profile of physicochemical and functional properties of flour of some of the OFSP cultivars produced in Limpopo province, South Africa has been drawn. This study also highlights the nutritional quality of the flour from four sweet potato cultivars and provides a ranking of flour to help the producers in the selection process. Bophelo flour was ranked the highest in terms of β- and, α-carotenes, total carotenoids and antioxidant capacity while Impilo was ranked highest in terms of functional properties and ash content. This study has highlighted significant differences in a number of parameters measured among the sweet potato cultivars. Therefore, in order to derive the maximum benefit from aIn recent years, there has been a lot of interest in orange fleshed sweet potato (OFSP) [Ipomoea batatas (L.) Lam] cultivar, as a cheaper source of vitamin A. In Southern Africa, reports have shown that one in every three children has deficiency in vitamin A. This study investigated the variations in β-carotene (vitamin A precursor) content among selected OFSP cultivars grown in Limpopo Province, South Africa. In addition, the study investigated the effects of location on functional properties, total carotenoids and antioxidant profile of the sweet potato flour as well as their physicochemical, functional and nutritional properties. Four (4) sweet potato cultivars [Dagga, Bophelo, Impilo (orange fleshed) and Mvuvhelo (cream fleshed)] were obtained from two locations, namely, University of Venda (Univen) agricultural experimental farm and Tshiombo irrigation scheme (Tshiombo) and analysed for pasting, functional, physicochemical and nutritional properties. The sweet potato flours from these two locations were also analysed by computed tomographic (CT) scans for flour particle density. Mineral and microstructure of OFSP flours were analysed by scanning electron microscope (SEM). All measurements, except the tristimulus L* a* b* and other colour parameters from five replicates, were performed in triplicate. Statistical analysis was performed using a one-way analysis of variance and means were separated using Duncan’s multiple range test; P < 0.05 was considered to be statistically significant. Pearson’s correlation coefficients were used to determine the correlation among functional, physicochemical, nutritional and pasting properties of sweet potato flour. β-carotene content varied significantly between the two locations from 70.98 ± 0.8 μg/g (Tshiombo) to 86.09 ± 2.0 μg/g (Univen), among cultivars from 1.71 ± 0.0 μg/g (Mvuvhelo) to 201.50 ± 1.0 μg/g (Dagga) and among orange fleshed (Dagga, Bophelo and Impilo) flours from 28.38 ± 0.2 μg/g (Impilo) to 201.50 ± 1.0 μg/g (Dagga). There was a similar trend in the contents of α-carotene to that of β-carotene from the two locations, which ranged from 0.63 ± 0.0 mol/L (Tshiombo) to 1.01 ± 0.0 mol/L (Univen). Mvuvhelo had significantly the lowest α-carotene content (0.50 ± 0.0 mol/L) and Impilo the highest (1.28 ± 0.0 mol/L). The total carotenoids was highest for Impilo (7.56 μg/g) and lowest for Mvuvhelo (1.33 ± 0.1 μg/g) but did not vary significantly (P > 0.05) between ii the locations. The antioxidant activity, based on 2, 2-diphenyl-1picrylhydrazyl (DPPH) free radical scavenging activity, was significantly highest in Bophelo (63.37 ± 0.8 mMAAE ml-1) and lowest in Dagga (26.93 ± 1.4 mMAAE ml-1) flours. The ferric reducing antioxidant power (FRAP) varied significantly across the locations and among the cultivars and ranged from 14.45 ± 0.3 μMTE ml-1 (Tshiombo) to 17.40 ± 1.1 μMTE ml-1 (Univen). FRAP was significantly highest in Impilo (21.12 ± 2.1 μMTE ml-1) and lowest in Mvuvhelo (8.16 ± 2.0 μMTE ml-1). Total carotenoid content positively correlated with DPPH (0.486*), FRAP (0.830**), β-carotene (0.370*), and α-carotene (0.424*). The antioxidant content and the radical scavenging activity were significantly correlated (0.563**). Vitamin A content was significantly lowest (6.88 ± 0.38 μg/g retinol) in Dagga flour and highest (7.97 ± 0.25 μg/g) in Impilo flour. Protein content varied significantly across the two locations and ranged from 4.23% (Tshiombo) to 7.16% (Univen). Dagga had significantly the lowest (3.47%) protein content while Impilo had the highest (7.53%). The fat content of the flours varied significantly between the two locations ranging from 0.63% (Tshiombo) to 1.01% (Univen). The protein content was positively correlated 0.594** and 0.421* to vitamin A and fat contents respectively. The Bophelo colour luminosity was significantly lower (L* 76.2) than the other two OFSP, Dagga (L* 83.51) and Impilo (L* 82.07). Bophelo a* (14.09) also differed significantly across all sweet potato cultivars. All cultivars differed significantly in b* values. Colour intensity (ΔE*) ranged from 15.87 to 38.48 for Mvuvhelo and Bophelo, respectively. Chroma ranged from 87.52 to 84.95 for Dagga and Mvuvhelo respectively. Total starch content was significantly different in all sweet potato cultivars and ranged from 244.07 μg/100 g (Bophelo) to 325.04 mg/g (Dagga). Resistant starch differed significantly in all sweet potato cultivars ranging from 1.21 μg/100 g dwb (Bophelo) to 7.07 μg/100 g dwb (Impilo). Ash content was significantly different in all cultivars and ranged from 3.17% (Dagga) to 3.79% (Bophelo). Water holding capacity (WHC) varied significantly across the two locations and ranged from 1.44 g H2O/g DM (Tshiombo) to 1.72 g H2O/g DM (Univen). Bophelo had significantly the lowest (1.27 g H2O/g DM) WHC and Impilo the highest (1.99 g H2O/g DM). The ash content negatively correlated to total starch (-0.928**) but positively iii correlated to WHC (0.654**). Peak viscosity differed significantly across all cultivars under study and ranged from 126.54 RVU (Bophelo) to 302.36 RVU. (Dagga). There was significant difference in trough viscosity across all cultivars ranging from 55.97 RVU (Impilo) to 280.78 RVU (Dagga). There were significant differences in the final viscosity across all cultivars ranging from 78.99 RVU (Impilo) to 319.26 (Dagga). Peak time viscosity varied significantly across all cultivars ranging from 3.87 min (Impilo) to 8.47 min. (Bophelo). Dagga cultivar had significantly the highest pasting temperature (94.16oC) and Bophelo the lowest (77.75oC). The setback viscosity was significantly highest 51.10 RVU (Mvuvhelo) and lowest 23.01 RVU (Impilo). All cultivars from the two locations consistently showed high potassium content ranging from 0.46% (Impilo) to 1.38% (Dagga) as compared to other minerals such as magnesium, calcium and chlorine which ranged from 0.16% (Impilo) to 0.34%. (Dagga). The CT scans revealed that there was a possibility of evaluating the effect of location on the density of granules of sweet potato flour and also the inherent differences in granular distribution of various sweet potato cultivars. SEM revealed high amounts of potassium, magnesium and chlorine. A profile of physicochemical and functional properties of flour of some of the OFSP cultivars produced in Limpopo province, South Africa has been drawn. This study also highlights the nutritional quality of the flour from four sweet potato cultivars and provides a ranking of flour to help the producers in the selection process. Bophelo flour was ranked the highest in terms of β- and, α-carotenes, total carotenoids and antioxidant capacity while Impilo was ranked highest in terms of functional properties and ash content. This study has highlighted significant differences in a number of parameters measured among the sweet potato cultivars. Therefore, in order to derive the maximum benefit from a given cultivar careful selection of sweet potato cultivars would be necessary.

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