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Fate and effect of naphthenic acids in biological systemsMisiti, Teresa Marie 23 August 2012 (has links)
Naphthenic acids (NAs) are carboxylic acids found in crude oil and petroleum products. The objectives of the research presented here were to: a) assess the occurrence and fate of NAs in crude oil and refinery wastewater streams; b) evaluate the biotransformation potential and inhibitory effects of NAs under nitrifying, denitrifying and methanogenic/fermentative conditions; c) investigate the factors affecting NA biotransformation under aerobic conditions and the microbes involved; and d) assess the toxicity of individual model NAs using quantitative structure-activity relationships (QSAR) and examine the effect of structure on NA biotransformation potential. NAs are ubiquitous in refinery wastewater streams and the desalter brine was found to be the main source of NAs in refinery wastewater. A commercial NA mixture was not biodegraded under nitrate-reducing or methanogenic/fermentative conditions. NAs were degraded under aerobic conditions by an NA-enriched culture; however, a residual fraction was not degraded under all conditions studied. The results indicated that NAs are not inherently recalcitrant and the residual fraction was due to the individual NA concentrations being below the minimum substrate concentrations at which they are no longer degraded. A fraction of the NA mixture was completely mineralized to carbon dioxide, with the remaining portion biotransformed to more oxidized intermediates. Overall, the results indicated that NAs were degraded under aerobic conditions; however, biological treatment of NA-bearing wastewater will not completely remove NA concentrations and thus, biological treatment must be combined with physical/chemical treatment to achieve complete NA removal.
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Separating Acetate, Formate and MSA from natural samples using ion chromatography / Separera Acetat, Format och MSA från naturliga prover med jonkromatografiDrake, Alexandra January 2013 (has links)
Anjoner från de tre korta organiska syrorna: acetat, format och MSA är intressanta att mäta då de kan användas för olika sorters miljöstudier. Jonkromatografen vid Institutionen för Geovetenskaper kan för närvarande inte skilja på dessa tre ämnen, därför utvecklades sex nya metoder i detta projekt för att lösa problemet. Metod 5 visade sig vara den bästa, där acetat och format separerades. Resultatet ansågs vara bra, även om MSA inte separerades. Metod 5 testades sedan på ett par naturliga prover; vatten-, snö- och isprover. Alla dessa prover visade en större mängd av format än acetat, som i vissa fall inte ens visades. Resultaten verkade rimliga, inte många av dem stack ut i jämförelse till andra resultat av samma fas. Det ytligaste provet från Lomonosovfonnaglaciären skiljer sig dock ganska mycket i mängden format jämfört med prover från andra djup av denna iskärna, förmodligen på grund av kontamination vid hanteringen av proverna både vid provtagningen och i labbet. MSA kan dock även mätas om man vet mängden acetat och format i provet. Detta görs genom tillsats av kända mängder av MSA till samma prov i efterföljande körningar, för att sedan kunna beräkna koncentrationen av MSA i provet. Problemet med denna metod är att koncentrationen av MSA måste vara tillräckligt hög i kontrast till koncentrationerna av acetat och format för att få tillförlitliga resultat, vilket den inte var i det här projektets analyserade prover. / Anions from three short organic acids: acetate, formate and MSA are interesting to measure since they can be used for different environmental studies. The ion-chromatographer at the Department of Earth Sciences is currently not able to separate these three substances; therefore six new methods were developed in this project to solve this problem. Short organic test 5 ended up to be the best method, where acetate and formate were separated. The result was considered good, even if MSA were not separated. Method 5 was then tested on a couple of natural water, snow and ice samples. All these samples showed a larger amount of formate than of acetate, which in some cases was not even found. The results seemed plausible; not many of them were sticking out compared to others of the same phase. The shallowest sample from the Lomonosovfonna ice cap did however differ quite a lot in amount of formate compared with samples from other depths of this ice core; probably because of contamination which could have occurred at both the ice cap and in the lab during the handling of the samples. MSA can however also be measured if the amount of acetate and formate in the sample is known. This is done by adding known amounts of MSA to the same sample in subsequent runs to then be able to calculate the concentration of MSA in the sample. The problem with the use of this method is that the concentration of MSA needs to be high enough in contrast to acetate and formate in order to get reliable results, which was not the case in the samples measured in this project.
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Theoretical investigation of polar zinc oxide surface modification via phosphonic acid self-assembled monolayersWood, Christopher Alan 17 January 2012 (has links)
The interface of a zinc-terminated polar zinc oxide surface (0002) with a series of chemisorbed fluorinated benzylphosphonic acids has been studied using density functional theory. The calculations indicate that there is a substantial change in the binding energies and work function modification depending on the binding motif. The results also indicate that there is a pronounced difference in the magnitude and trends of the factors determining the total change in work function. The oxygen core-level binding shifts have been calculated and compared to available experimental data.
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CONCEPTUALIZING AND IMPROVING RED WINE GRAPE CULTIVARS GROWN IN KENTUCKYSimson, Matthew 01 January 2011 (has links)
Wine sensory attributes are associated with quality of wines. Cabernet Franc did not possess good coloration of its wine. Therefore, in the 2009 and 2010 growing seasons, studies including the sampling of four red wine grape cultivars from the end of flowering throughout the rest of the season and applying treatments to Cabernet Franc grapevines at veraison were commenced to address suitability and color enhancement, respectively. The study examining Cabernet Franc, Cabernet Sauvignon, Chambourcin, and Norton looked at sampling their grapes at two-week intervals from times post-flowering to understand the demands of each cultivar during key stages of berry development, in particular berry maturation post-veraison. The French-American hybrids Chambourcin and Norton were found to accumulate high levels of anthocyanins, also termed high cultivar performance, while the Vitis vinifera L. cultivars of Cabernet Franc and Cabernet Sauvignon remained stable in their anthocyanin content post-veraison. The results of the treatments applied to Cabernet Franc as a possible exogenous amelioration for anthocyanin pigment deficit in this cultivar support use of treatments for improving coloration in Cabernet Franc in Kentucky.
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A metabolomics study of selected perturbations of normal human metabolism / Elmarie Davoren.Davoren, Elmarie January 2010 (has links)
Metabolism is an integrated network of biochemical pathways involving a series of enzymecatalysed
anabolic or catabolic reactions in cells. Metabolites are chemical compounds that are
involved in or are products of metabolic pathways, and the metabolome is defined as the total
complement of all the low molecular weight metabolites present in a cell at any given time.
Metabolomics is a relatively new research technology utilised for the global investigation,
identification and quantification of the metabolome. Three aims were defined for the
metabolomics study presented here:
• The use of metabolomics technology to generate new biological information;
• Application of the metabolomics technology to gain information on the three natural
perturbations, namely the menstrual cycle, pregnancy and aging; and
• Reflection on metabolomic studies as a hypothesis-generating approach.
I obtained three sets of urine samples from women during their menstrual cycle, samples from
sixteen pregnant and eleven non-pregnant women for the second natural perturbation, and data
sets from previous investigations on infant and child groups, as well as thirty-two urine samples
from adults for the study of the metabolomic profiles due to age. These urine samples were
analysed to determine the organic acid metabolite profiles. The metabolites were identified by
means of AMDIS and were manually quantified. Data matrixes were compiled, which underwent
certain data reduction steps, prior to statistical analysis. Different statistical approaches were
used to generate information on these three natural perturbations due to the clear differences
between the three experimental groups used. The investigation of the menstrual cycle did not
show a distinct difference between the three phases involved in the cycle, whereas the
pregnancy perturbation showed a difference between pregnant groups and non-pregnant
groups. The most pronounced difference in metabolite profiles were found when the different
age groups were compared to one another. Finally a hypothesis on the effect of age on
metabolism was defined and an experimental approach was proposed to evaluate this
hypothesis.
In conclusion three proposals were formulated from this investigation:
1. If it appears that an insufficient number of participants can be generated for a
metabolomics study, such a study should be discarded in the interest of a more feasible
investigation.
2. It is advisable that a number of appropriate analytical validation parameters should be
incorporated in the early stages of a metabolomics study, specifically linked to the
context of the perturbation chosen for the investigation. 3. The control and experimental groups should be homogenous that is to say as
comparable as possible with regard to age, ethnicity, diet, and gender, lifestyle habits
and other possible confounding influences, except for the specific perturbation being
studied. In a perfect world this would be possible, specifically when hypothesis
formulation, testing and finally the expansion of scientific knowledge is a desired
outcome of the investigation. / Thesis (M.Sc. (Biochemistry))--North-West University, Potchefstroom Campus, 2010.
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A metabolomics study of selected perturbations of normal human metabolism / Elmarie Davoren.Davoren, Elmarie January 2010 (has links)
Metabolism is an integrated network of biochemical pathways involving a series of enzymecatalysed
anabolic or catabolic reactions in cells. Metabolites are chemical compounds that are
involved in or are products of metabolic pathways, and the metabolome is defined as the total
complement of all the low molecular weight metabolites present in a cell at any given time.
Metabolomics is a relatively new research technology utilised for the global investigation,
identification and quantification of the metabolome. Three aims were defined for the
metabolomics study presented here:
• The use of metabolomics technology to generate new biological information;
• Application of the metabolomics technology to gain information on the three natural
perturbations, namely the menstrual cycle, pregnancy and aging; and
• Reflection on metabolomic studies as a hypothesis-generating approach.
I obtained three sets of urine samples from women during their menstrual cycle, samples from
sixteen pregnant and eleven non-pregnant women for the second natural perturbation, and data
sets from previous investigations on infant and child groups, as well as thirty-two urine samples
from adults for the study of the metabolomic profiles due to age. These urine samples were
analysed to determine the organic acid metabolite profiles. The metabolites were identified by
means of AMDIS and were manually quantified. Data matrixes were compiled, which underwent
certain data reduction steps, prior to statistical analysis. Different statistical approaches were
used to generate information on these three natural perturbations due to the clear differences
between the three experimental groups used. The investigation of the menstrual cycle did not
show a distinct difference between the three phases involved in the cycle, whereas the
pregnancy perturbation showed a difference between pregnant groups and non-pregnant
groups. The most pronounced difference in metabolite profiles were found when the different
age groups were compared to one another. Finally a hypothesis on the effect of age on
metabolism was defined and an experimental approach was proposed to evaluate this
hypothesis.
In conclusion three proposals were formulated from this investigation:
1. If it appears that an insufficient number of participants can be generated for a
metabolomics study, such a study should be discarded in the interest of a more feasible
investigation.
2. It is advisable that a number of appropriate analytical validation parameters should be
incorporated in the early stages of a metabolomics study, specifically linked to the
context of the perturbation chosen for the investigation. 3. The control and experimental groups should be homogenous that is to say as
comparable as possible with regard to age, ethnicity, diet, and gender, lifestyle habits
and other possible confounding influences, except for the specific perturbation being
studied. In a perfect world this would be possible, specifically when hypothesis
formulation, testing and finally the expansion of scientific knowledge is a desired
outcome of the investigation. / Thesis (M.Sc. (Biochemistry))--North-West University, Potchefstroom Campus, 2010.
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Skirtingo organinių rūgščių kiekio įtaka dėsliųjų vištų produktyvumui bei kiaušinių kokybei / The influence of different amount of organic acid to the productivity of the laying hens and the quality of eggsNorkutė, Justina 18 June 2014 (has links)
Lesinimo bandymas truko 56 dienas ir buvo atliktas su 30 savaičių Hisex Brown linijų derinio 36 vnt. dėsliųjų vištų. Paukščiai buvo suskirstyti į 3 grupes, kiekvienoje grupėje po 12 vištų. Visų grupių vištos buvo lesinamos standartiniais kombinuotaisiais lesalais. Kontrolinės grupės vištos buvo lesinamos tik standartiniais kombinuotaisiais lesalais, į I tiriamosios grupės kombinuotuosius lesalus buvo įmaišyta organinių rūgščių priedo, kurio dozavimas 1,5 kg/t lesalų, į II tiriamosios grupės kombinuotuosius lesalus įterpta organinių rūgščių priedo 2 kg/t lesalų. Lumance priedai – 1,5 kg/t ir 2,0 kg/t – esminės įtakos vištų masės dinamikai nebuvo nustatytas. Minėti priedai mažino vištų dėslumą sumažino 2-4 proc., o lesalų konversijai bei išsaugojimui esminės įtakos nenustatyta. Naudoti Lumance priedai sumažino tyrimų vištų masę 3-5 proc. Lumance priedas 1,5 kg/t lesalų padidino lukšto stiprumą 10 proc., baltymo aukštį 9 proc., Hafo vienetus – 6 proc., lukšto storį – 3 proc., palyginus su kontroline grupe. Lumance priedai omega – 6 ir omega – 3 kiekiui bei santykiui, hypocholesterolemijos/hypercholesterolemijos, peroksidavimosi, aterogeniškumo ir trombogeniškumo indeksams tiek šviežiuose kiaušiniuose, tiek sandėliuotuose 28 dienas esminės įtakos neturėjo. Juslinės šviežių kiaušinių baltymo ir trynio savybės buvo labai artimos, nenustatyta, kad naudoti priedai būtų turėję reikšmingos įtakos kvapo, skonio, spalvos ar tekstūros savybių intensyvumui. Išlaikius kiaušinius 28 paras... [toliau žr. visą tekstą] / The feeding experiment took 56 days and was performed on the 36 Hisex Brown layer fowl of 30 weeks old. Hens were divided into 3 groups of 12 hens in each. The fowl of all 3 groups were fed with a standard composite feed. The fowl in the auditorial group were only fed with the standard composite feed whilst the composite feed of the first investigative group was mixed with an organic acid supplement of a dosage 1,5kg/tn of feed and finally the composite feed of the second investigative group was combined with an organic acid supplement of a dosage 2kg/tn of feed. The influence was not detected of the Lumance supplements (1,5kg/t and 2kg/t) to the body growth of the fowl. The mentioned supplements reduced fowl productivity by 2-4% however the influence was not detected to the conversion of feed and preservation. Used Lumance supplements reduced the body weight of examined fowl by 3-5%. Lumance supplement of 1,5kg/t feed increased the strength of the hull by 10% and the height of albumen by 9%, the units of Haf – by 6% and the thickness of the hull by 3% in comparison with the auditorial group. Lumance accessories omega - 6 and omega - 3 and the quantity proportion hypercholesterolemia/ hypercholesterolemia, peroxidation, atherogenic and thrombogenicity indices both fresh eggs and warehoused for 28 days had no significant influence.The sensual features of yolk and albumen of fresh eggs were very close and it was not established a significant influence of the used supplements... [to full text]
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Organinių rūgščių mišinio Lumance įtaka dėsliųjų vištų kiaušinių kokybei / The influence of organinic acids mixture Lumance on laying hens egg qualityMenkevičius, Andrius 18 June 2014 (has links)
Sveikas žarnynas – vienas pagrindinių veiksnių, pagal kurį reglamentuojamas paukščių efektyvumas ir paukštienos gamybos ekonomika. Žarnyno mikrofloros sudėtis yra svarbi žarnyno sveikatos palaikyme. Maistinės organinės rūgštys ir jų druskos gali slopinti mikroorganizmų augimą maiste, tuo būdu išsaugant mikroorganizmų balansą virškinamajame trakte. Be to, pakeisdamos žarnyno pH, organinės rūgštys taip pat pagerina lesalų sudedamųjų dalių tirpumą, maistinių medžiagų virškinimą ir absorbciją. Tačiau organinių rūgščių panaudojimas vištų mityboje priklauso nuo organinių rūgščių ar jų druskų sudėties, įterpiamo kiekio į lesalus, lesalų gamybos technologinių parametrų, paukščių fiziologinės būklės; duomenys apie minėtų priedų įtaką kiaušinių kokybei yra prieštaringi. Todėl magistrinio darbo tikslas – ištirti organinių rūgščių mišinio Lumance įtaką dėsliųjų vištų kiaušinių kokybei. / Gut health is one of the major factors in regard to the performance of poultry and thus, economics of production. The profile of the intestinal microflora plays an important role in gut health. Dietary organic acids and their salts are able to inhibit microorganism growth in the food, and consequently to preserve the microbial balance in the gastrointestinal tract. In addition, by modifying intestinal pH, organic acids also improve the solubility of the feed ingredients, digestion and absorption of nutrients. However the use of organic acids in poultry diet very depends on composition of organic acids or their salts, used dose in poultry feed, parameters of technology of poultry feed production, poultry physiology; data on use of those additives are very controversial. Therefore the main purpose of final work is to determine the influence of organic acids mixture Lumance on laying hens’ egg quality.
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Cereal non-starch polysaccharides in pig diets : influence on digestion site, gut environment and microbial populations /Högberg, Ann, January 2003 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 5 uppsatser.
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Host selection and antifeedants in Hylobius abietis pine weevils /Månsson, Per E, January 2005 (has links) (PDF)
Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniversitet, 2005. / Härtill 4 uppsatser.
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