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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.
11

Estudio de prefactibilidad para la implementación de una planta de producción de aceite de Sacha Inchi (Plukenetia Volubilis)

Gómez-de-la-Torre-Cateriano, Lourdes, Lazo-Cánepa, Diego-Julio January 2015 (has links)
Este proyecto presenta el estudio preliminar para la implementación de una planta de producción de aceite de Sacha Inchi (Plukenetia Volubilis), a partir de las semillas de esta misma. Para determinar si el proyecto es viable, se realizó un arduo estudio de mercado, con el cuál determinamos la demanda del proyecto utilizando como referencia su principal y más utilizado producto sustituto, el aceite de oliva. Para extraer la información, se utilizó una gran cantidad de bases de datos, entre ellas Euromonitor, Ipsos Apoyo, entre otras. Así mismo se realizó un estudio para determinar el tamaño y la localización de planta en el Perú, utilizando herramientas aprendidas en el transcurso de la carrera de Ingeniería Industrial, como Guerchet, ranking de factores, diagramaciones, etc. Los cuales fueron de mucha ayuda para determinar el lugar de localización y su tamaño adecuado, optimizando los espacios necesarios, la cercanía de la maquinaria y a su vez, optimizar los costos de producción. / This project presents the preliminary study for a production plant of Sacha Inchi Oil (Plukenetia Volubilis). To determine if the project is viable, we made an arduous market study. We used these results in addition to the reference of its substitute product the Olive Oil to determine the demand. To obtain the information, it was used a lot of databases, among them Euromonitor, Ipsos Apoyo, among others. In addition, a study to determine the size and location of the plant in Peru was made, using tools learned in the course of Industrial Engineering, as Guerchet, “Ranking de factores”, layouts and others. These methods, which were very helpful to determine the place of location and adequate size of the plant, also help us optimize the space needed, the proximity of machinery and optimize production costs. / Trabajo de investigación
12

The Johannesburg Gas Works - Restoring Significance through Restitution

Basson, Nellis January 2018 (has links)
Cities keep expanding as people move towards more desired locations on the outskirts, resulting in abandoned, dead nodes within the city centre. These buildings are left to deteriorate, especially those of heritage and cultural importance. Designed with a very specific function in mind, industrial architecture is mostly removed from society, hidden behind infrastructure. The process and economics are what drives the architecture. But what happens when this industry fails, or become of no value to mankind? What is left behind except for the scarred ecology? This architecture that was specifically designed for this mono-functional purpose? Decay sets in: what was once a producer becomes no more than a relic - socially abandoned because it was never social to begin with. The growth in technology as well as the realization that many of the ways in which old industries used to function has had an immense negative effect on the environment. A calling for new, better ways of doing things were needed; though it has left our city landscapes scattered with industrial objects, from mine dumps to power plants, abandoned and without purpose. There is an ethical responsibility that should address this and to reactivate these areas by re-appropriating these nodes by making them into desired locations for businesses as well as residents. The challenge being in finding an appropriate use for such nodes that will help the city flourish. Re-appropriating such architecture will put a new focus and livelihood on it, as well as its surrounding precinct. By utilizing and re-appropriating the architecture, it will eliminate, or at least lessen, the chances of it becoming another abandoned monument. This dissertation will highlight and investigate the importance of industrial architecture as an object of heritage for South Africa. This will be done by looking at the manner in which the architecture at the Johannesburg Gas Works can be re-purposed and re-imagined in contributing to an ever-evolving city and its people, by giving the existing structures a new purpose. There is therefore a need to keep the heritage of the Gas Works alive because the architecture, and the site as such, has become obsolete to the purpose it was built for. / Mini Dissertation MArch(Prof)--University of Pretoria, 2018. / Architecture / MArch(Prof) / Unrestricted
13

Olive oil or lard?: distinguishing plant oils from animal fats in the archeological record of the eastern Mediterranean using gas chromatography/combustion/isotope ratio mass spectrometry

Steele, V. J., Stern, B., Stott, A. W. January 2010 (has links)
Distinguishing animal fats from plant oils in archaeological residues is not straightforward. Characteristic plant sterols, such as beta-sitosterol, are often missing in archaeological samples and specific biomarkers do not exist for most plant fats. Identification is usually based on a range of characteristics such as fatty acid ratios, all of which indicate that a plant oil may be present, none of which uniquely distinguish plant oils from other fats. Degradation and dissolution during burial alter fatty acid ratios and remove short-chain fatty acids, resulting in degraded plant oils with similar fatty acid profiles to other degraded fats. Compound-specific stable isotope analysis of delta(13)C(18:0) and delta(13)C(16:0), carried out by gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS), has provided a means of distinguishing fish oils, dairy fats, ruminant and non-ruminant adipose fats, but plant oils are rarely included in these analyses. For modern plant oils where C(18:1) is abundant, delta(13)C(18:1) and delta(13)C(16:0) are usually measured. These results cannot be compared with archaeological data or data from other modern reference fats where delta(13)C(18:0) and delta(13)C(16:0) are measured, as C(18:0) and C(18:1) are formed by different processes resulting in different isotopic values. Eight samples of six modern plant oils were saponified, releasing sufficient C(18:0) to measure the isotopic values, which were plotted against delta(13)C(16:0). The isotopic values for these oils, with one exception, formed a tight cluster between ruminant and non-ruminant animal fats. This result complicates the interpretation of mixed fatty residues in geographical areas where both animal fats and plant oils were in use.
14

Effects of tea seed oil and onion on lipoprotein metabolism in hamsters. / CUHK electronic theses & dissertations collection

January 2010 (has links)
Cardiovascular disease (CVD) is a major health problem in developed countries and, with increasing prevalence in developing countries and Eastern Europe. Due to the increased incidence with advancing age, there is a need to develop primary preventive interventions to prolong the period of healthy life. Diet has a substantial influence on health and aging. The composition of the human diet plays an important role in the management of lipid and lipoprotein. In this respect, we have focused on the effects of two kinds of functional foods, tea seed oil and dietary onion on their hypocholesterolemic activities and underlying mechanisms in the present study. / Clearly, there are many claims on health benefits of Alliums , however, most, with the exception of garlic, have not received any rigorous or even gentle scientific investigation. Thus, the present study was carried out to explore hypocholesterolemic effects of onion supplementation. After fed for 2 weeks of the high fat high cholesterol diet, thirty-six 8-week male hamsters were divided into four groups. Control group was continued fed with high fat high cholesterol diet, while the other two experimental groups were fed control diet plus 1% (1OP) and 5% (5OP) onion powder for 8 weeks. It was found that feeding high dose of onion powder diet significantly prevented the increase in serum TC, Non-HDL-C and the ratio of non-HDL-C/HDL respectively in hamsters fed a 0.1% cholesterol diet. In contrast, the ratio of HDL/TC in high dose group was significantly increased than that in the control. Low onion dose group tended to have the similar effects as high dose group but, statistically, no difference was observed between the control and low dose groups. Besides, both doses of onion powder diets could significantly countered the increase in serum TG levels. High dose of onion supplementation tended to increase output of fecal neutral and acidic sterols, resulting in reduction of cholesterol retained and absorption. High dose of onion powder diet could significantly up- regulate SREBP-2, LXRbeta, and CYP7A1 protein expressions. The hypocholesterolemic activities of onion might due to the richness in alkyl and alkenyl sulfoxide compounds, anthocyanin, quercetin and cycloalliin, all of which have therapeutic effects. / In conclusion, diet plays an important role in reducing the risk of CVD. This has led to the search for specific foods and food components that may help to improve the serum lipoprotein profile. In present study, tea seed oil and onion was proved to help favorably modify the plasma lipoprotein profile, serving as health supplementation. However, their potential mechanisms were not fully studied and need to be further explored. / Interest in tea seed oil (named tea oil) as a cooking oil is increasing. However, its effect on blood cholesterol is not known. This study was therefore conducted to compare the hypocholesterolemic activity of tea oil with grape seed, canola and corn oils. Fifty 8-week-old male hamsters were first fed a high fat diet (5% lard), and supplemented with 0.1% cholesterol for 2 weeks and then divided into five groups. Control group was continuously fed high fat high cholesterol diet, while the experimental groups were fed high fat, high cholesterol diet plus 10% tea oil, grape seed oil, canola oil and corn oil for 12 weeks. Results showed that plasma total cholesterol (TC), non-HDL-cholesterol (non-HDL-C) and triacylglycerols (TG) in hamsters fed a 0.1% cholesterol diet containing tea, grape, canola or corn oil was significantly reduced compared with those in lard-fed group. Tea oil decreased only non-HDL-C and had no or little effect on HDL-C concentration, while grape oil reduced both. Besides, tea oil-fed hamsters excreted less neutral but greater acidic sterols compared with other three oils. Unlike grape oil, tea oil up-regulated sterol regulatory element binding protein (SREBP-2) and LDL receptor. Differences between tea oil and the tested vegetable oils could be attributable partially to >80% oleic acid in tea oil. / Guan, Lei. / Adviser: Chung Hau Yin. / Source: Dissertation Abstracts International, Volume: 72-04, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 98-125). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
15

Synthèse de nouveaux polyesters “verts” issus de ressources oléagineuses : application au renfort au choc du poly(L-lactide) / Synthesis of novel “green” polyesters from plant oils : application to the rubber-toughening of poly(L-lactide)

Lebarbe, Thomas 06 December 2013 (has links)
Dans cette étude, plusieurs voies ont été explorées dans l’objectif d’utiliser des polyesters aliphatiques issus de ressources oléagineuses comme additifs pour le renfort au choc du poly(L-lactide) (PLLA). Dans un premier temps, des poly(ester-amide)s (PEAs) ont été synthétisés à partir de dérivés de l’huile de ricin. La relation structure-propriétés des PEAs obtenus a été clairement établie. La dispersion des PEAs (à différents taux) par extrusion à l’état fondu dans une matrice de PLLA a ensuite été effectuée, démontrant un accroissement de la résilience de ces mélanges en comparaison au PLLA seul. Une étude systématique reliant la structure d’une large gamme de polyesters aux propriétés des mélanges polyesters/PLLA, a ensuite été réalisée. Une forte dépendance de la résilience des mélanges polyesters/PLLA avec la cristallinité de l’additif polyester a été observée et quantifiée.Une amélioration des propriétés mécaniques du PLLA a également été obtenue par polymérisation par ouverture de cycle du lactide amorcée par un poly(acide ricinoléique) di-hydroxy téléchélique. Les copolymères triblocs ainsi formés ont été caractérisés d’un point de vue morphologique et mécanique.Enfin, un travail exploratoire utilisant l’ADMET comme méthode de polymérisation a été conduit, permettant la synthèse de nouveaux polymères prometteurs pour le renfort au choc du PLLA. Notamment, la copolymérisation de α,ω-diènes bio-sourcés a permis de mimer le polyéthylène basse densité linéaire, couramment employé pour le renfort au choc du PLLA. / The objective of this thesis work, is to promote the use of fatty acid-based aliphatic polyesters as impact modifiers for poly(L-lactide) (PLLA).Firstly, poly(ester-amide)s (PEAs) have been synthesized from castor oil derivatives. The structure-properties relationship of the PEAs so-formed was clearly established. The PEAs were then melt-blended with PLLA by extrusion, yielding blends with improved impact strength compared to neat PLLA.A series of polyesters covering a wide range of thermo-mechanical properties was then employed to evaluate the influence of the polyester morphology on the properties of the blends with PLLA. A strong dependence of the impact strength of the blends was noticed with the crystallinity degree of the polyester additive.An improvement of the mechanical properties of PLLA was also obtained by ring-opening polymerization of lactide initiated by a di-hydroxy telechelic poly(ricinoleic acid). The so-formed triblock copolymers were fully characterized in terms of morphology and mechanical properties.Finally, an exploratory investigation related to the synthesis of PLLA impact modifiers by ADMET was carried out. Particularly, the copolymerization of two bio-based α,ω-dienes yielded a series of “LLDPE like” polyesters, LLDPE being a commonly used impact modifier for PLLA.
16

Farmakološki efekti etarskog ulja ruzmarina Rosmarinus officinalis, L. (Lamiaceae), na miševima soja NMRI-Haan i pacovima soja Wistar / Pharmacological effects of rosemary essential oil Rosmarinus officinalis, L. (Lamiaceae), on mice of strain NMRI-Haan and rats of strain Wistar

Milanović Isidora 09 July 2015 (has links)
<p>Ruzmarin Rosmarinus officinalis L. (Lamiaceae) je biljka koja se u tradicionalnoj medicini na na&scaron;em području koristi za postizanje analgetičkog, holeretičkog i hepatoprotektivnog delovanja. Prema Evropskoj agenciji za lekove (2010 godine), indikacije za sistemsku primenu etarskog ulja ruzmarina su lečenje dispepsije i spazama gastrointestinalnog trakta, a za spolja&scaron;nju primenu se preporučuje u lečenju umereno jakih bolova u zglobovima i mi&scaron;ićima i u lečenju poremećaja periferne cirkulacije. Imajući u vidu da komponente etarskog ulja ruzmarina ispoljavaju i druga, potencijalno korisna farmakolo&scaron;ka svojstva, postoji potreba da se ova delovanja detaljnije ispitaju. Ciljevi ispitivanja su bili da se utvrdi: 1) analgetički efekat etarskog ulja ruzmarina i njegov uticaj na farmakodinamske osobine paracetamola, kodeina, diazepama i pentobarbitala kao i na farmakokinetske osobine paracetamola; 2) antioksidativni i hepatoprotektivni efekat u uslovima hemijski izazvanog oksidativnog stresa. Metodom gasne hromatografije (GC/MS i GC/FID) utvrđen je kvantitativni sastav etarskog ulja. Najzastupljenije komponente ulja koje je kori&scaron;ćeno u na&scaron;em ispitivanju su oksidovani monoterpeni 1,8-cineol (43.77%) i kamfor (12.53%) i monoterpenski ugljovodonik &alpha;-pinen (11.51%). Suspenzija etarskog ulja ruzmarina primenjivana je mi&scaron;evima u dozama 10 i 20 mg/kg tm tokom sedam dana i jednokratno u farmakodinamskim testovima: test vrele ploče, test &bdquo;uvijanja&ldquo; (posle intraperitonealne primene sirćetne kiseline), test za procenu motorne koordinacije životinja na rotirajućem &scaron;tapu i test merenja vremena trajanja spavanja. Za ispitivanje uticaja etarskog ulja ruzmarina na farmakokinetske osobine paracetamola i za biohemijska i toksikolo&scaron;ka ispitivanja, kori&scaron;ćeni su pacovi koji su tokom sedam dana tretirani suspenzijom etarskog ulja ruzmarina u dozi 5 i 10 mg/kg tm, a sedmog dana su primili paracetamol i.v. ili p.o.. Za praćenje farmakokinetskih parametara kori&scaron;ćeni su uzorci krvi dobijeni iz repne vene pacova u kojima su HPLC metodom merene koncentracije paracetamola, na osnovu kojih su potom određeni farmakokinetski parametri ovog leka. Antioksidativna aktivnost etarskog ulja ruzmarina je određivana in vitro (DPPH i Folin-Ciocaulteu testovima) i in vivo. Nakon žrtvovanja životinja iz prikupljenih uzoraka krvi određivani su iz seruma biohemijski parametri, pokazatelji bubrežne i jetrene funkcije, a u homogenatu tkiva jetre određivani su parametri oksidativnog stresa. Samo etarsko ulje ruzmarina ispoljava analgetičko delovanje i smanjuje visceralnu bol izazvanu sirćetnom kiselinom. Pored toga, potencira analgetički efekat kodeina i paracetamola. Etarsko ulje ruzmarina značajno smanjuje hipnotičko delovanje pentobarbitala i sprečava poremećaj motorne koordinacije nakon primene diazepama. Etarsko ulje ruzmarina ne utiče značajnije na oralnu biolo&scaron;ku raspoloživost paracetamola. Vi&scaron;ekratna primena različitih doza etarskog ulja ruzmarina ne izaziva toksične promene u krvi i jetri ispitivanih životinja. Primena etarskog ulja ruzmarina &scaron;titi životinje od reaktivnih kiseoničnih vrsta, umanjuje posledice izloženosti oksidativnom stresu i ispoljava značajno hepatoprotektivno delovanje.</p> / <p>Rosemary Rosmarinus officinalis, L.(Lamiaceae) is traditionally used in folk medicine for its analgetic, choleretic and hepatoprotective properties. According to the recommendation of European Medicines Agency from 2010, rosemary essential oil can be used for treating dyspepsia and mild spasmodic disorders of the gastrointestinal tract, and also externally as an adjuvant in the relief of minor muscular and articular pain and minor peripheral circulatory disorders. Different studies conducted with rosemary essential oil show other pharmacological effects of main components of the oil. The aim of this study was to examine: 1) analgetic effects of rosemary essential oil and its influence on the pharmacodynamic properties of paracetamol, codeine, diazepam and pentobarbital, and also its influence on the pharmacokinetic properties of paracetamol; 2) antioxidant and hepatoprotective effects on the parameters of chemicaly induced oxidative stress. The quantification of chemical constituents of the essential oil was carried out by gas chromatography (GC/FID and GC/MS). The major compounds that were identified and quantitated by GC-FID and GC-MS were oxygenated monoterpens 1,8-cineole (43.77%), camphor (12.53%) and monoterpene hydrocarbon &alpha;-pinene (11.51%). The suspension of rosemary essential oil was applied to mice orally (doses: 10 and 20 mg/kg b.w.) for seven days and in single dose for the pharmacodynamic tests: hot plate, writhing, rotharod and sleeping time. Rats treated with suspension of rosemary essential oil for seven days orally (doses: 5 and 10 mg/kg b.w.) were used for the examination of influence of essential oil on the pharmacokinetic properties of paracetamol. Then on the 7th day the paracetamol was applied to them p.o. or i.v.. The parameters of pharmacokinetic were analyzed in blood samples obtained from rats tail veins. The HPLC method was used for measurement of concentration of paracetamol in blood samples. Those concentrations were used for calculation of the pharmacokinetic parameters. The antioxidant activity of the rosemary essential oil was evaluated in vitro (with DPPH and Folin-Ciocaulteu tests) and in vivo. The animals were sacrificed and the samples of blood and liver were taken. The obtained serum was used for determination of standard biochemical parameters and the parameters of oxidative stress were analyzed in obtained liver homogenates. The essential oil of rosemary shows analgetic properties and it decreases visceral pain induced with intraperitoneally injected acetic acid. The rosemary essential oil increases pharmacological effects of codeine and paracetamol. Also, this oil reduces pentobarbital-induced sleeping time and diminishes diazepam-induced disorder of psychomotor coordination. The essential oil of rosemary does not change paracetamol bioavailability. The rosemary essential oil applied in multiple doses does not induce toxic changes in blood and liver samples obtained from animals. The use of rosemary essential oil protects animals from reactive oxygen species, decreases the effects caused by oxidative stress and shows significant hepatoprotective effect.</p>
17

Air-Assited Atomization Strategies For High Viscosity Fuels

Mohan, Avulapati Madan 08 1900 (has links) (PDF)
Atomization of fuel is an important pre-requisite for efficient combustion in devices such as gas turbines, liquid propellant rocket engines, internal combustion engines and incinerators. The overall objective of the present work is to explore air-assisted atomization strategies for high viscosity fuels and liquids. Air-assisted atomization is a twin-fluid atomization method in which energy of the gas is used to assist the atomization of liquids. Broadly, three categories of air-assisted injection, i.e., effervescent, impinging jet and pre-filming air-blast are studied. Laser-based diagnostics are used to characterize the spray structure in terms of cone angle, penetration and drop size distribution. A backlit direct imaging method is used to study the macroscopic spray characteristics such as spray structure and spray cone angle while the microscopic characteristics are measured using the Particle/droplet imaging analysis (PDIA) technique. Effervescent atomization is a technique in which a small amount of gas is injected into the liquid at high pressure in the form of bubbles. Upon injection, the two-phase mixture expands rapidly and shatters the liquid into droplets and ligaments. Effervescent spray characteristics of viscous fuels such as Jatropha and Pongamia pure plant oils and diesel are studied. Measurements are made at various gas-to-liquid ratios (GLRs) and injection pressures. A Sauter Mean Diameter (SMD) of the order of 20 µm is achieved at an injection pressure of 10 bar and GLR of 0.2 with viscous fuels. An image-based method is proposed and applied to evaluate the unsteadiness in the spray. A map indicating steady/unsteady regime of operation has been generated. An optically accessible injector tip is developed which has enabled visualization of the two-phase flow structure inside the exit orifice of the atomizer. An important contribution of the present work is the correlation of the two-phase flow regime in the orifice with the external spray structure. For viscous fuels, the spray is observed to be steady only in the annular two-phase flow regime. Unexpanded gas bubbles observed in the liquid core even at an injection pressure of 10 bar indicate that the bubbly flow regime may not be beneficial for high viscosity oils. A novel method of external mixing twin-fluid atomization is developed. In this method, two identical liquid jets impinging at an angle are atomized using a gas jet. The effect of liquid viscosity (1 cP to 39 cP) and surface tension (22 mN/m to 72 mN/m) on this mode of atomization is studied by using water-glycerol and water-ethanol mixtures, respectively. An SMD of the order of 40 µm is achieved for a viscosity of 39 cP at a GLR of 0.13 at a liquid pressure of 8 bar and gas pressure of 5 bar. It is observed that the effect of liquid properties is minimal at high GLRs where the liquid jets are broken before the impingement as in the prompt atomization mode. Finally, a pre-filming air-blast technique is explored for transient spray applications. An SMD of 22 µm is obtained with diesel at liquid and gas pressures as low as 10 bar and 8.5 bar, respectively. With this technique, an SMD of 44 µm is achieved for Jatropha oil having a viscosity 10 times higher than that of diesel.
18

Olive oil or lard? Distinguishing plant oils from animal fats in the archaeological record of the eastern Mediterranean using gas chromatography/combustion/isotope ratio mass spectrometry

Steele, Valerie J., Stern, Ben, Stott, A.W. 15 December 2010 (has links)
Yes / Distinguishing animal fats from plant oils in archaeological residues is not straightforward. Characteristic plant sterols, such as ¿-sitosterol, are often missing in archaeological samples and specific biomarkers do not exist for most plant fats. Identification is usually based on a range of characteristics such as fatty acid ratios, all of which indicate that a plant oil may be present, none of which uniquely distinguish plant oils from other fats. Degradation and dissolution during burial alter fatty acid ratios and remove short chain fatty acids, resulting in degraded plant oils with similar fatty acid profiles to other degraded fats. Compound specific stable isotope analysis of ¿13C18:0 and ¿13C16:0, carried out by gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS), has provided a means of distinguishing fish oils, dairy fats, ruminant and non-ruminant adipose fats but plant oils are rarely included in these analyses. For modern plant oils where C18:1 is abundant, ¿13C18:1 and ¿13C16:0 are usually measured. These results cannot be compared with archaeological data or other modern reference fats where ¿13C18:0 and ¿13C16:0 are measured, as C18:0 and C18:1 are formed by different processes resulting in different isotopic values. Eight samples of six modern plant oils were saponified releasing sufficient C18:0 to measure the isotopic values, which were plotted against ¿13C16:0. The isotopic values for these oils, with one exception, formed a tight cluster between ruminant and non-ruminant animal fats. This result complicates the interpretation of mixed fatty residues in geographical areas where both animal fats and plant oils were in use. / AHRC

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